TY - JOUR TI - A Latent Risk Approach for Modeling Individual Level Data Consisting of Multiple Event Times AU - Ghosh, S.K. AU - Gelfand, A.E. T2 - Journal of Statistical Research DA - 1998/// PY - 1998/// VL - 32 IS - 1 SP - 23–38 ER - TY - CONF TI - Bayesian Analysis of Change-point Hazard Rate Models AU - Ghosh, S. T2 - Conference on Reliability and Survival Analysis C2 - 1998/5// CY - Northern Illinois University, DeKalb, IL DA - 1998/5// PY - 1998/5// ER - TY - SOUND TI - Analyzing Real Estate Data Problems using Gibbs Sampler AU - Ghosh, S. DA - 1998/3// PY - 1998/3// ER - TY - CONF TI - Analyzing Real Estate Data Problems using Gibbs Sampler AU - Ghosh, S. T2 - Joint Statistical Meetings C2 - 1998/8/13/ CY - Dallas, TX DA - 1998/8/13/ PY - 1998/8/13/ ER - TY - SOUND TI - Bayesian Imputation Methods for Missing Data AU - Ghosh, S. DA - 1998/11/19/ PY - 1998/11/19/ ER - TY - BOOK TI - Review: Linear Models AU - Ghosh, Sujit K. AU - Moser, Barry Kurt DA - 1998/3// PY - 1998/3// DO - 10.2307/2669642 VL - 93 PB - JSTOR SE - 402 UR - http://dx.doi.org/10.2307/2669642 ER - TY - BOOK TI - The foundations of social research meaning and perspective in the research process1998 AU - Crotty, Michael DA - 1998/// PY - 1998/// PB - London ;|aThousand Oaks, Calif: Sage Publications ER - TY - JOUR TI - Puncture resistance of pre-strained geotextile membrane and its relation to uniaxial tensile strain at failure AU - ghosh, T2 - Geotextiles and Geomembranes AB - Abstract The principal focus of this study is the puncture resistance of geotextiles under uniform radial pre-strain. A test frame which can apply preset radial strain and measure puncture resistance of geotextiles has been developed. A number of commercially available woven and nonwoven geotextile materials have been evaluated for puncture resistance while held under a preset radial strain. The test results show lower failure strain in puncture if the test sample is pre-strained. The failure strain measured in wide width tensile tests are much higher than calculated strains in puncture. DA - 1998/// PY - 1998/// DO - 10.1016/s0266-1144(98)00011-9 VL - 16 SP - 293–302 ER - TY - CONF TI - Development of an instrument for the evaluation of biaxial stress-strain response of fabrics AU - Ghosh, T.K C2 - 1998/// C3 - Book of papers : INDA-TEC 98, largest International Nonwovens Conference : September 15-17, 1998, Trump Plaza Hotel, Atlantic City, NJ. DA - 1998/// PB - Cary, NC: INDA, Association of the Nonwoven Fabrics Industry ER - TY - JOUR TI - Exposure of differentiated rodent airway epithelial cells in vitro to particles of residual fly ash (ROFA) induces cytotoxicity and generation of reactive oxygen species. AU - Adler, K. B. AU - Jiang, N. F. AU - Dye, J. A. AU - Dreher, K. L. T2 - Proceedings of the 10th International Colloquium on Lung Fibrosis DA - 1998/// PY - 1998/// VL - 10 SP - 26 ER - TY - JOUR TI - Predictive tests for structural change with unknown breakpoint AU - Ghysels, E AU - Guay, A AU - Hall, A T2 - JOURNAL OF ECONOMETRICS AB - This paper considers predictive tests for structural change in models estimated via Generalized Method of Moments. Our analysis extends earlier work by Ghysels and Hall (1990a) by allowing for the instability to occur at an unknown point in the sample. We analyse various statistics based on continuous mappings of the sequence of predictive test calculated for a set of possible breakpoints in the sample. The limiting distribution of these statistics is derived under both the null hypothesis and local alternatives. Percentiles are reported for the distribution under the null. A sideproduct of our analysis is that we can illuminate the power properties of the predictive test and also compare its properties to those of the Wald, LR and LM tests for parameter variation. We study those power properties both via local asymptotic analysis and Monte Carlo. DA - 1998/2// PY - 1998/2// DO - 10.1016/S0304-4076(97)00057-2 VL - 82 IS - 2 SP - 209-233 SN - 0304-4076 KW - generalized method of moments KW - nonlinear models KW - structural stability testing KW - parameter variation KW - overidentifying restrictions ER - TY - JOUR TI - A longitudinal study of engineering student performance and retention. v. comparisons with traditionally-taught students AU - Felder, R. M. AU - Felder, G. N. AU - Dietz, E. J. T2 - Journal of Engineering Education AB - Abstract In a longitudinal study at North Carolina State University, a cohort of students took five chemical engineering courses taught by the same instructor in five consecutive semesters. The courses made extensive use of active and cooperative learning and a variety of other techniques designed to address a broad spectrum of learning styles. Previous reports on the study summarized the instructional methods used in the experimental course sequence, described the performance of the cohort in the introductory chemical engineering course, and examined performance and attitude differences between students from rural and urban backgrounds and between male and female students. 1–4 This paper compares outcomes for the experimental cohort with outcomes for students in a traditionally‐taught comparison group. The experimental group outperformed the comparison group on a number of measures, including retention and graduation in chemical engineering, and many more of the graduates in this group chose to pursue advanced study in the field. Since the experimental instructional model did not require small classes (the smallest of the experimental classes had 90 students) or specially equipped classrooms, it should be adaptable to any engineering curriculum at any institution. DA - 1998/// PY - 1998/// DO - 10.1002/j.2168-9830.1998.tb00381.x VL - 87 IS - 4 SP - 469-480 ER - TY - CHAP TI - Statistical methods employed in evaluation of single-locus probe results in criminal identity cases AU - Weir, B. S. T2 - Forensic DNA profiling protocols (Methods in molecular biology (Clifton, N.J.) ; 98) A2 - P. J. Lincoln, A2 - Thomson, J. PY - 1998/// VL - 98 SP - 83-96 PB - Totowa, N.J.: Humana Press ER - TY - JOUR TI - Prediction of yarn tensile properties based on HVI testing of 36 U.S. upland cottons AU - Suh, M. W. AU - Koo, H.-J. AU - Cui, X. T2 - Beltwide Cotton Conferences. Proceedings DA - 1998/// PY - 1998/// VL - 1 IS - 1998 SP - 786-790 ER - TY - JOUR TI - On-line measurement of fabric bending behavior: background, need and potential solutions AU - Zhou, N. Y. AU - ghosh, T2 - International Journal of Clothing Science and Technology AB - Low‐stress mechanical properties of fabrics are very important in many applications as well as in manufacturing process control. Discusses the importance and potential applications of an on‐line mechanical property measurement system. In addition, the working principles of existing off‐ line fabric bending testers have been critically reviewed. It is suggested that the principle of a future on‐line system to evaluate fabric bending behaviour should be based on the characterisation of fabric loop shapes. DA - 1998/// PY - 1998/// DO - 10.1108/09556229810213845 VL - 10 IS - 2 SP - 143–154 ER - TY - BOOK TI - Estimation of population structure parameters, final report AU - Weir, B. S. DA - 1998/// PY - 1998/// PB - Rockville, MD: National Institute of Justice ER - TY - JOUR TI - Estimation of HVI bundle modulus and toughness as determinants to tensile properties of spun yarns AU - Suh, M. W. AU - Koo, H.-J. AU - Watson, M. D. T2 - Beltwide Cotton Conferences. Proceedings DA - 1998/// PY - 1998/// VL - 2 IS - 1998 SP - 1530-1536 ER - TY - BOOK TI - Characterizing population structure for assigning weight to DNA matching profiles AU - Weir, B. S. AU - Buckleton, J. S. DA - 1998/// PY - 1998/// PB - Rockville, MD: National Institute of Justice ER - TY - CONF TI - Long-term diapause and spreading of risk across the life cycle AU - Ellner, S. P. AU - Hairston, N. G., Jr. AU - Babai, D. A2 - L. Brendonck, L. de Meester A2 - Hairston, N., Jr. C2 - 1998/// C3 - Evolutionary and ecological aspects of crustacean diapause: Proceedings of the symposium 'Diapause in the Crustacea--with invited contributions on non-crustacean taxa' held in Gent, August 24-29, 1997 (Ergebnisse der Limnologie=Advances in limnology series; Heft. 52) DA - 1998/// SP - 297-312 PB - Stuttgart: E. Schweizerbart'sche Verlagsbuchhandlung ER - TY - JOUR TI - Reshaping expectations for web-based collaborative learning AU - Hess, G. R. AU - Abt, R. AU - Serow, R. T2 - Natural Resources and Environmental Issues DA - 1998/// PY - 1998/// VL - 7 IS - 1998 SP - 104-109 ER - TY - CHAP TI - Evaluating a web-based course AU - Serow, R. C. AU - Hess, G. R. AU - Abt, R. C. AU - Ukpabi, C. V. T2 - Program evaluation handbook PY - 1998/// SP - 57-60 PB - Needham Heights, Mass.: Simon & Schuster Custom Publishing SN - 0536010536 ER - TY - JOUR TI - Combining change-in-ratio, index-removal, and removal models for estimating population size AU - Chen, CL AU - Pollock, KH AU - Hoenig, JM T2 - BIOMETRICS AB - There are three methods that can be used to estimate population size when survey data are collected just before and just after two or more known harvests: change-in-ratio, index-removal, and catch-effort (removal) methods. In this paper, we introduce a methodology that combines all three methods. We begin by modeling the survey and removal processes as a Poisson point process and a linear death process, respectively, and then we combine the two processes. The completedata likelihood can be factored into three parts: the general likelihood function of the index-removal method, the general likelihood function of the change-in-ratio method, and the general likelihood function of the catch-effort method. We compute the maximum likelihood estimates using the Powell search algorithm. Monte Carlo simulations are used to demonstrate that the estimates from combining change-in-ratio, index-removal, and catch-effort methods are more precise than the estimates based on combining any two of them or only using a single method. An example based on snow crab data is presented to illustrate the methodology. DA - 1998/9// PY - 1998/9// DO - 10.2307/2533836 VL - 54 IS - 3 SP - 815-827 SN - 1541-0420 KW - animal populations KW - catch-effort method KW - change-in-ratio method KW - combining likelihoods KW - index-removal method KW - removal method KW - sampling ER - TY - CHAP TI - Regional and temporal models for ozone along the Gulf Coast AU - Davis, J. M. AU - Eder, B. K. AU - Bloomfield, P. T2 - Case studies in environmental statistics A2 - D. Nychka, W. W. Piegorsch A2 - Cox, L. H. AB - The studies described in the previous chapter focused on estimating trends in a daily ozone summary having adjusted for the relationship of surface ozone concentrations to meteorology. Moreover, the analysis was largely restricted to the Chicago urban area. This chapter contrasts this narrow scope by studies that: CN - GE45.S73 C38 1998 PY - 1998/// DO - 10.1007/978-1-4612-2226-2_3 SP - 27-50 PB - New York: Springer ER - TY - JOUR TI - Periodograms of unit root time series: Distributions and tests AU - Akdi, Y AU - Dickey, DA T2 - COMMUNICATIONS IN STATISTICS-THEORY AND METHODS AB - Periodograms are often used to characterize time series. They decompose the variation in the data into periodic components and their statistical properties for stationary series are well understood. The periodogram can be computed for any sequence of numbers and we are interested in studying its statistical properties when the underlying data have a time series structure with a unit root. Knowing these properties gives us the ability to look at nonstationarity on a frequency by frequency basis. The pervasive use of periodogram ordinates in applied work and the frequent occurrence of apparently nonstationary data in practice are sufficient alone to motivate interest in these distributions, however we also suggest a way to use the results in a formal test for unit roots. The test has the advantage of using nonseasonal ordinates of the periodogram, thus being invariant to regular periodicities in the data. Section 1 of the paper is introductory. Section 2 develops the periodogram and a convenient normalization for an autoregressive process of order 1, leading to distributional results and a table of percentiles. In section 3, an extension is made to general processes in which the first difference is a stationary autoregressive moving average. The effect of a deterministic trend or drift on the periodogram is considered in Section 4 and an adjustment for trend is given in Section 5. Interestingly, it will be seen that the adjustment has an advantage over the usual time domain tests for unit roots in that standard x2 distributions result. Tests based on the periodogram and their power properties are displayed with examples in Section 6. An advantage of these tests is their invariance to deterministic seasonal components which, for the example series, is a reasonably likely scenario In the second example on retail sales, it is seen that breaking trends can also be accommodated with a minor modification of this technique and the advantage of having standard distributions will become apparent DA - 1998/// PY - 1998/// DO - 10.1080/03610929808832651 VL - 27 IS - 1 SP - 69-87 SN - 0361-0926 KW - frequency KW - integration ER - TY - JOUR TI - Nonlinear adjustment of a rotating homogeneous atmosphere to zonal momentum forcing AU - Weglarz, RP AU - Lin, YL T2 - TELLUS SERIES A-DYNAMIC METEOROLOGY AND OCEANOGRAPHY DA - 1998/10// PY - 1998/10// DO - 10.1034/j.1600-0870.1998.t01-4-00004.x VL - 50 IS - 5 SP - 616-636 SN - 0280-6495 ER - TY - CHAP TI - Modeling ozone in the Chicago urban areas AU - Davis, J. M. AU - Eder, B. K. AU - Bloomfield, P. T2 - Case studies in environmental statistics A2 - D. Nychka, W. W. Piegorsch A2 - Cox, L. H. AB - Ozone (O3) is a ubiquitous trace gas in the atmosphere. Its highest concentration is in the stratosphere, where it shields the earth’s surface from harmful ultraviolet radiation. At the surface, however, ozone is itself harmful, with destructive impacts on materials, crops, and health. Its levels have been high enough in certain areas to be of concern for several decades. CN - GE45.S73 C38 1998 PY - 1998/// DO - 10.1007/978-1-4612-2226-2_2 SP - 5-26 PB - New York: Springer ER - TY - JOUR TI - Estimating the rate of evolution of the rate of molecular evolution AU - Thorne, JL AU - Kishino, H AU - Painter, IS T2 - MOLECULAR BIOLOGY AND EVOLUTION AB - A simple model for the evolution of the rate of molecular evolution is presented. With a Bayesian approach, this model can serve as the basis for estimating dates of important evolutionary events even in the absence of the assumption of constant rates among evolutionary lineages. The method can be used in conjunction with any of the widely used models for nucleotide substitution or amino acid replacement. It is illustrated by analyzing a data set of rbcL protein sequences. DA - 1998/12// PY - 1998/12// DO - 10.1093/oxfordjournals.molbev.a025892 VL - 15 IS - 12 SP - 1647-1657 SN - 0737-4038 KW - molecular clock KW - phylogeny KW - Markov chain Monte Carlo KW - Metropolis-Hastings algorithm ER - TY - JOUR TI - Estimating the parameters in the Cox model when covariate variables are measured with error AU - Hu, P AU - Tsiatis, AA AU - Davidian, M T2 - BIOMETRICS AB - The Cox proportional hazards model is commonly used to model survival data as a function of covariates. Because of the measuring mechanism or the nature of the environment, covariates are often measured with error and are not directly observable. A naive approach is to use the observed values of the covariates in the Cox model, which usually produces biased estimates of the true association of interest. An alternative strategy is to take into account the error in measurement, which may be carried out for the Cox model in a number of ways. We examine several such approaches and compare and contrast them through several simulation studies. We introduce a likelihood-based approach, which we refer to as the semiparametric method, and show that this method is an appealing alternative. The methods are applied to analyze the relationship between survival and CD4 count in patients with AIDS. DA - 1998/12// PY - 1998/12// DO - 10.2307/2533667 VL - 54 IS - 4 SP - 1407-1419 SN - 0006-341X KW - cumulative hazards KW - measurement error KW - nonparametric maximum likelihood KW - proportional hazards model KW - regression calibration KW - semiparametric method ER - TY - JOUR TI - Estimating the number of active and successful bald eagle nests: an application of the dual frame method AU - Haines, DE AU - Pollock, KH T2 - ENVIRONMENTAL AND ECOLOGICAL STATISTICS DA - 1998/9// PY - 1998/9// DO - 10.1023/A:1009673403664 VL - 5 IS - 3 SP - 245-256 SN - 1352-8505 KW - domain KW - estimation KW - multiple frame sampling KW - sample KW - screening estimator ER - TY - JOUR TI - Asymptotic properties of maximum likelihood estimates for a bivariate exponential distribution and mixed censored data AU - Chen, D AU - Lu, JC AU - Hughes-Oliver, JM AU - Li, CS T2 - METRIKA DA - 1998/// PY - 1998/// DO - 10.1007/s001840050003 VL - 48 IS - 2 SP - 109-125 SN - 0026-1335 KW - asymptotic theory KW - Marshall-Olkin distribution KW - concomitants of order statistics KW - life-testing KW - maximum likelihood estimation ER - TY - BOOK TI - Applied regression analysis: A research tool AU - Rawling, J. O. AU - Pantula, S. G. AU - Dickey, D. A. CN - QA278.2 .R38 1998 DA - 1998/// PY - 1998/// PB - New York: Springer SN - 0387984542 ER - TY - BOOK TI - Statistical genomics: Linkage, mapping and QTL analysis AU - Liu, B.-H. CN - QH438.4 .S73 L55 1998 DA - 1998/// PY - 1998/// PB - Boca Raton, FL: CRC Press SN - 0849331668 ER - TY - JOUR TI - Non-parametric MLE for Poisson species abundance models allowing for heterogeneity between species AU - Norris, JL AU - Pollock, KH T2 - ENVIRONMENTAL AND ECOLOGICAL STATISTICS DA - 1998/12// PY - 1998/12// DO - 10.1023/A:1009659922745 VL - 5 IS - 4 SP - 391-402 SN - 1352-8505 KW - bootstrap KW - ecological diversity and evenness KW - goodness-of-fit test KW - likelihood ratio test KW - mixture model ER - TY - JOUR TI - A spatially explicit stochastic model demonstrates the feasibility of Wright's Shifting Balance Theory AU - Peck, SL AU - Ellner, SP AU - Gould, F T2 - EVOLUTION DA - 1998/12// PY - 1998/12// DO - 10.2307/2411353 VL - 52 IS - 6 SP - 1834-1839 SN - 1558-5646 KW - diffusion approximation KW - Sewall Wright KW - shifting-balance theory KW - stochastic simulation models KW - substructured populations ER - TY - JOUR TI - Variance estimators in the Chu-White test for structural change AU - Park, YJ AU - Pantula, SG T2 - COMMUNICATIONS IN STATISTICS-SIMULATION AND COMPUTATION AB - Abstract In this paper, we consider the Chu‐White test for a change in the trend parameter in a simple linear regression model with correlated errors. Chu‐White test requires a consistent estimator of the error variance. The main goal of this paper is to study the choice of the variance estimates. We consider several variance estimators and study the power of the Chu‐White test under different choices of the variance estimators. Keywords: Change in trendBrownian bridgeFractional ARIMA(0,d,0)ARCH(1) DA - 1998/// PY - 1998/// DO - 10.1080/03610919808813523 VL - 27 IS - 4 SP - 1019-1029 SN - 0361-0918 KW - change in trend KW - Brownian bridge KW - fractional ARIMA(O,d,O) KW - ARCH(1) ER - TY - JOUR TI - Parametric nonstationary correlation models AU - Hughes-Oliver, JM AU - Gonzalez-Farias, G AU - Lu, JC AU - Chen, D T2 - STATISTICS & PROBABILITY LETTERS AB - Stochastic processes observed over space often exhibit nonstationarity. Possible causes of nonstationarity include mean drift, heterogeneity of responses, or a correlation pattern that is not simply a function of the Euclidean distance between two spatial locations. This paper considers the latter. The need for nonstationary correlation models has been demonstrated in several application areas, including environmental monitoring of pollutants, and modeling of semiconductor fabrication processes. We present parametric nonstationary correlation models for capturing the effect of point sources. For example, if the response variable is carbon monoxide, then a smoke stack producing carbon monoxide would be considered a point source, and it is unreasonable to believe that correlation would not depend on proximity to the smoke stack. Our parametric models allow the consideration of multiple-point sources, as well as testing the strength of a particular source. These models have the usual anisotropic and isotropic exponential correlation functions as special cases. DA - 1998/10/15/ PY - 1998/10/15/ DO - 10.1016/S0167-7152(98)00103-5 VL - 40 IS - 3 SP - 267-278 SN - 0167-7152 KW - anisotropy KW - point source KW - pollution monitoring KW - positive semidefinite kernel KW - positive semidefinite matrix KW - semi-conductor fabrication ER - TY - JOUR TI - PASSML: combining evolutionary inference and protein secondary structure prediction AU - Lio, P AU - Goldman, N AU - Thorne, JL AU - Jones, DT T2 - BIOINFORMATICS AB - Evolutionary models of amino acid sequences can be adapted to incorporate structure information; protein structure biologists can use phylogenetic relationships among species to improve prediction accuracy. Results : A computer program called PASSML ('Phylogeny and Secondary Structure using Maximum Likelihood') has been developed to implement an evolutionary model that combines protein secondary structure and amino acid replacement. The model is related to that of Dayhoff and co-workers, but we distinguish eight categories of structural environment: alpha helix, beta sheet, turn and coil, each further classified according to solvent accessibility, i.e. buried or exposed. The model of sequence evolution for each of the eight categories is a Markov process with discrete states in continuous time, and the organization of structure along protein sequences is described by a hidden Markov model. This paper describes the PASSML software and illustrates how it allows both the reconstruction of phylogenies and prediction of secondary structure from aligned amino acid sequences.PASSML 'ANSI C' source code and the example data sets described here are available at http://ng-dec1.gen.cam.ac.uk/hmm/Passml.html and 'downstream' Web pages.P.Lio@gen.cam.ac.uk DA - 1998/// PY - 1998/// DO - 10.1093/bioinformatics/14.8.726 VL - 14 IS - 8 SP - 726-733 SN - 1367-4803 ER - TY - JOUR TI - Nitrate effect on carbon and nitrogen assimilating enzymes of maize hybrids representing seven eras of breeding AU - Purcino, A. A. C. AU - Arellano, C. AU - Athwal, G. S. AU - Huber, S. C. T2 - Maydica DA - 1998/// PY - 1998/// VL - 43 IS - 2 SP - 83-94 ER - TY - JOUR TI - Anatomic site and interanimal variability in morphologic characteristics of bottlenose dolphin (Tursiops truncatus) skin likely to affect dermal absorption studies AU - Colbert, A. A. AU - Stoskopf, M. AU - Brownie, C. AU - Scott, G. I. AU - Levine, J. T2 - American Journal of Veterinary Research DA - 1998/// PY - 1998/// VL - 59 IS - 11 SP - 1398-1403 ER - TY - CONF TI - Using computer algebra systems to teach graduate mathematical statistics: potential and pitfalls AU - Berger, R. L. C2 - 1998/// C3 - Statistical education: Expanding the Network. Proceedings of the Fifth International Conference on Teaching of Statistics. International Statistical Institute, 1998. DA - 1998/// VL - 1 SP - 189-195 M1 - 1998 ER - TY - JOUR TI - Statistical properties of fitted estimates of apparent in vivo metabolic constants obtained from gas uptake data. I. Lipophilic and slowly metabolized VOCs AU - Smith, A. E. AU - Evans, M. V. AU - Davidian, M. T2 - Inhalation Toxicology DA - 1998/// PY - 1998/// VL - 10 IS - 5 SP - 383-409 ER - TY - JOUR TI - Predicted and inferred waiting times for key mutations in the germinal centre reaction: Evidence for stochasticity in selection AU - Radmacher, MD AU - Kelsoe, G AU - Kepler, TB T2 - IMMUNOLOGY AND CELL BIOLOGY AB - The germinal centre reaction (GCR) is a fundamental component of the immune response to T‐dependent antigens, during which the immunoglobulin (Ig) genes of B cells experience somatic hypermutation and selection. A maximum‐likelihood method on DNA sequence data from 16 individual germinal centres was used to infer that the waiting time for position 33 key (high‐affinity) mutations in the anti‐(4‐hydroxy‐3‐nitrophenyl) acetyl (NP) response is 8.3 days. This is in marked contrast to the prediction of a key mutant each generation (waiting time about 1/3 day) obtained from a simple model and parameters available in the literature. This disagreement is resolved in part by the finding that the targeted base occurs in a cold spot for hypermutation, raising the predicted waiting time to 2.3 days, although this value remains significantly lower than that inferred from the sequence data. It is proposed that the remaining disparity is attributable to some further stochastic process in the GCR: many early key mutations arise but fail to ‘take root’ within the GC, either due to emigration or failure of cognate T cell/B cell interaction. Furthermore, it is argued that the frequency with which position 33 mutations are found in secondary responses to NP indicates the presence of selection after the GCR. DA - 1998/8// PY - 1998/8// DO - 10.1046/j.1440-1711.1998.00753.x VL - 76 IS - 4 SP - 373-381 SN - 1440-1711 KW - b-lymphocytes KW - germinal centre KW - immunoglobulins KW - maximum likelihood estimates KW - statistical models ER - TY - CHAP TI - Plasticity under somatic mutation in antigen receptors AU - Kepler, T. B. AU - Bartl, S. T2 - Somatic diversification of immune responses (Current topics in microbiology and immunology ; 229) A2 - G. Kelsoe, A2 - Flajnik, M. F. CN - QR1 .E6 1998 PY - 1998/// VL - 229 SP - 149-162 PB - Berlin; New York: Springer ER - TY - JOUR TI - Modeling the effects of meteorology on ozone in Houston using cluster analysis and generalized additive models AU - Davis, JM AU - Eder, BK AU - Nychka, D AU - Yang, Q T2 - ATMOSPHERIC ENVIRONMENT AB - This paper compares the results from a single-stage clustering technique (average linkage) with those of a two-stage technique (average linkage then k-means) as part of an objective meteorological classification scheme designed to better elucidate ozone’s dependence on meteorology in the Houston, Texas, area. When applied to twelve years of meteorological data (1981–1992), each clustering technique identified seven statistically distinct meteorological regimes. The majority of these regimes exhibited significantly different daily 1 h maximum ozone (O3) concentrations, with the two-stage approach resulting in a better segregation of the mean concentrations when compared to the single-stage approach. Both approaches indicated that the largest daily 1 h maximum concentrations are associated with migrating anticyclones that occur most often during spring and summer, and not with the quasi-permanent Bermuda High that often dominates the southeastern United States during the summer. As a result, maximum ozone concentrations are just as likely during the months of April, May, September and October as they are during the summer months. Generalized additive models were then developed within each meteorological regime in order to identify those meteorological covariates most closely associated with O3 concentrations. Three surface wind covariates: speed, and the u and v components were selected nearly unanimously in those meteorological regimes dominated by anticyclones, indicating the importance of transport within these O3 conducive meteorological regimes. DA - 1998/8// PY - 1998/8// DO - 10.1016/S1352-2310(98)00008-9 VL - 32 IS - 14-15 SP - 2505-2520 SN - 1352-2310 KW - ozone KW - cluster analysis KW - meteorology KW - generalized additive models KW - Houston ER - TY - JOUR TI - Inference methods for spatial variation in species richness and community composition when not all species are detected AU - Nichols, JD AU - Boulinier, T AU - Hines, JE AU - Pollock, KH AU - Sauer, , JR T2 - CONSERVATION BIOLOGY DA - 1998/12// PY - 1998/12// DO - 10.1046/j.1523-1739.1998.97331.x VL - 12 IS - 6 SP - 1390-1398 SN - 1523-1739 ER - TY - JOUR TI - Developmental quantitative genetics of growth in Populus AU - Wu, R AU - Bradshaw, HD AU - Stettler, RF T2 - THEORETICAL AND APPLIED GENETICS DA - 1998/11// PY - 1998/11// DO - 10.1007/s001220050998 VL - 97 IS - 7 SP - 1110-1119 SN - 0040-5752 KW - genetic correlation KW - growth KW - Populus KW - quantitative trait locus KW - seedling ER - TY - JOUR TI - Base temperature and heat unit requirement of 49 Mexican maize races AU - Ruiz, J. A. AU - Sanchez, J. J. AU - Goodman, M. M. T2 - Maydica DA - 1998/// PY - 1998/// VL - 43 IS - 4 SP - 277-282 ER - TY - JOUR TI - An individual-based, spatially-explicit simulation model of the population dynamics of the endangered red-cockaded woodpecker, Picoides borealis AU - Letcher, BH AU - Priddy, JA AU - Walters, , JR AU - Crowder, LB T2 - BIOLOGICAL CONSERVATION AB - Spatially-explicit population models allow a link between demography and the landscape. We developed a spatially-explicit simulation model for the red-cockaded woodpecker, Picoides borealis, an endangered and territorial cooperative breeder endemic to the southeastern United States. This kind of model is especially appropriate for this species because it can incorporate the spatial constraints on dispersal of helpers, and because territory locations are predictable. The model combines demographic data from a long-term study with a description of the spatial location of territories. Sensitivity analysis of demographic parameters revealed that population stability was most sensitive to changes in female breeder mortality, mortality of female dispersers and the number of fledglings produced per brood. Population behavior was insensitive to initial stage distribution; reducing the initial number of birds by one-half had a negligible effect. Most importantly, we found that the spatial distribution of territories had as strong an effect on response to demographic stochasticity as territory number. Populations were stable when territories were highly aggregated, with as few as 49 territories. When territories were highly dispersed, more than 169 territories were required to achieve stability. Model results indicate the importance of considering the spatial distribution of territories in management plans, and suggest that this approach is worthy of further development. DA - 1998/10// PY - 1998/10// DO - 10.1016/S0006-3207(98)00019-6 VL - 86 IS - 1 SP - 1-14 SN - 0006-3207 KW - red-cockaded woodpecker KW - individual-based model KW - spatially-explicit model KW - territory number KW - territory distribution KW - population dynamics ER - TY - JOUR TI - A Bayesian characterization of Hardy-Weinberg disequilibrium AU - Shoemaker, J. AU - Painter, I. AU - Weir, B. S. T2 - Genetics DA - 1998/// PY - 1998/// VL - 149 IS - 4 SP - 2079-2088 ER - TY - JOUR TI - Variability associated with testing shelled corn for fumonisin AU - Whitaker, T. B. AU - Trucksess, M. W. AU - Johansson, A. S. AU - Giesbrecht, F. G. AU - Hagler, W. M. AU - Bowman, D. T. T2 - Journal of AOAC International DA - 1998/// PY - 1998/// VL - 81 IS - 6 SP - 1162-1168 ER - TY - JOUR TI - The detection of plasticity genes in heterogeneous environments AU - Wu, RL T2 - EVOLUTION AB - The molecular genetic mechanisms for phenotypic plasticity across heterogeneous macro- and microenvironments were examined using the Populus genomic map constructed by DNA-based markers. Three hypotheses have been suggested to explain genetic variation in phenotypic response to varying environments (i.e., reaction norm): Lerner's homeostasis, allelic sensitivity, and gene regulation. The homeostasis hypothesis, which predicts that heterozygotes are less sensitive to the environment than homozygotes, was supported for phenotypic plasticity to unpredictable environments (microenvironmental plasticity) at the whole-genome level, but for phenotypic plasticity to predictable environments (macroenvironmental plasticity) the hypothesis was supported only at functioning quantitative trait loci (QTLs). For all growth traits studied, gene regulation was suggested to play a prevailing role in determining the norms of reaction to environments. Indirect evidence for gene regulation is that there tend to be more QTLs with larger effects on the phenotype in optimal growing conditions than suboptimal growing conditions because the expression of these QTLs identified is mediated by regulatory genes. Direct evidence for gene regulation is the identification of some loci that differ from QTLs for trait values within environments and exert an environmentally dependent control over structural gene expression. In this study, fewer environmentally sensitive QTLs were detected that display unparalleled allelic effects across environments. For stem height, there were more regulatory loci and more structural loci (whose expression is determined by gene regulation) affecting phenotypic plasticity than for basal area. It was found that microenvironmental plasticity was likely controlled by different genetic systems than those for macroenvironmental plasticity. DA - 1998/8// PY - 1998/8// DO - 10.1111/j.1558-5646.1998.tb01826.x VL - 52 IS - 4 SP - 967-977 SN - 1558-5646 KW - allelic sensitivity KW - phenotypic plasticity KW - Populus KW - QTL mapping KW - regulatory loci ER - TY - JOUR TI - On the radio-frequency inputs in dipolar heating of adhesives AU - Banks, H. T. AU - Durso, S. R. AU - Goodhart, M. A. AU - Joyner, M. L. T2 - Journal of Microwave Power and Electromagnetic Energy AB - The form of the radio-frequency (RF) or dielectric input expression in the heat equation which arises in the modeling of the curing of epoxy adhesives in bonding of composites was considered. Two standard derivations of a commonly used expression for the RF heating source term were reviewed. In this context difficulties involving the associated inherent polarization assumption and asymptotic behavior of dielectric parameters as a function of the frequency of the RF signal were discussed. These difficulties cast doubt on the validity of the standard RF expression. Two standard polarization models (Debye and Lorentz) then were used to demonstrate how one can systematically derive general RF heating expressions which do not suffer the inconsistencies that arise in the standard RF expression. DA - 1998/// PY - 1998/// DO - 10.1080/08327823.1998.11688380 VL - 33 IS - 4 SP - 231-242 ER - TY - JOUR TI - Multiyear tagging studies incorporating fishing effort data AU - Hoenig, JM AU - Barrowman, NJ AU - Hearn, WS AU - Pollock, KH T2 - CANADIAN JOURNAL OF FISHERIES AND AQUATIC SCIENCES AB - The Brownie models for multiyear tagging studies can be used to estimate age- and year-specific annual survival rates and tag recovery rates. The latter are composites of the exploitation rates and rates of tag reporting, tag shedding, and tag-induced mortality. It is possible to estimate the exploitation rates if the other components of the tag recovery rates can be quantified. Instantaneous rates of fishing and natural mortality can be estimated if information is available on the seasonal distribution of fishing effort. The estimated rates are only moderately dependent on the timing of the fishing; consequently, the relative effort data can be crude. Information on the timing of the catch over the course of the year can be used as a substitute for the effort data. Fishing mortality can also be assumed to be proportional to fishing effort over years; consequently, if fishing effort is known then the tag reporting rate, natural mortality rate, and a single catchability coefficient can be estimated (instead of natural mortality and a series of fishing mortalities). Although it is possible in theory to estimate both the tag reporting rate and the natural mortality rate with all of these models, in practice it appears necessary to obtain some additional data relating to tag reporting rate to obtain acceptable results. The additional data can come from a variable reward tagging study, a creel or port sampling survey, or from tagged animals that are secretly added to the fishers' catches. DA - 1998/6// PY - 1998/6// DO - 10.1139/cjfas-55-6-1466 VL - 55 IS - 6 SP - 1466-1476 SN - 1205-7533 ER - TY - JOUR TI - Models for tagging data that allow for incomplete mixing of newly tagged animals AU - Hoenig, JM AU - Barrowman, NJ AU - Pollock, KH AU - Brooks, EN AU - Hearn, WS AU - Polacheck, T T2 - CANADIAN JOURNAL OF FISHERIES AND AQUATIC SCIENCES DA - 1998/6// PY - 1998/6// DO - 10.1139/cjfas-55-6-1477 VL - 55 IS - 6 SP - 1477-1483 SN - 1205-7533 ER - TY - JOUR TI - Latent waiting time models for bivariate event times with censoring AU - Ghosh, S. K. AU - Gelfand, A. E. T2 - Sankhya. Series B DA - 1998/// PY - 1998/// VL - 60 IS - 1998 SP - 31-47 ER - TY - BOOK TI - Interpreting DNA evidence: Statistical genetics for forensic scientists AU - Evett, I. W. AU - Weir, B. S. CN - RA1057.5 .E945 1998 DA - 1998/// PY - 1998/// PB - Sunderland, MA: Sinauer Associates SN - 0878931554 ER - TY - JOUR TI - Applications of Basu's theorem AU - Boos, DD AU - Hughes-Oliver, JM T2 - AMERICAN STATISTICIAN DA - 1998/8// PY - 1998/8// DO - 10.2307/2685927 VL - 52 IS - 3 SP - 218-221 SN - 0003-1305 KW - ancillary statistic KW - Behrens-Fisher problem KW - complete family KW - Monte Carlo swindle KW - pivotal quantity KW - sufficient statistic ER - TY - JOUR TI - An optimum solution for scale-invariant object recognition based on the multiresolution approximation AU - Yoon, SH AU - Kim, JH AU - Alexander, WE AU - Park, SM AU - Sohn, KH T2 - PATTERN RECOGNITION AB - This paper presents a multiresolution approximation approach to obtaining boundary representations for object recognition. Our technique combines a multiresolution approximation and the curvature scale-space representation for obtaining representations. Our research consists of two main parts. In the first part of our research, we introduce the continuous multiresolution approximation (CMA) in terms of the continuous wavelet transform (CWT). Then we implement a fast algorithm to compute the CMA. We apply the CMA to a boundary to obtain approximations of the boundary at various resolutions. The CMA provides a consistent interpretation of objects with scale-variations. Moreover, we can quickly compute our representations by using the fast algorithm for the CMA. In the second part, we propose three representations for object recognition which cover most boundary-based object recognition problems. All three representations use the approximations obtained by the CMA. Each representation has different features and covers different types of matching problems but all representations are constructed by using curvature zero crossings of the approximations. Our representations provide a general but reliable solution to most boundary based object matching problems. Finally, we investigate the properties of our representations such as validity, efficiency, and reliability. We verified our results experimentally to demonstrate the feasibility of using our representations for object recognition. DA - 1998/7// PY - 1998/7// DO - 10.1016/S0031-3203(97)00111-8 VL - 31 IS - 7 SP - 889-908 SN - 0031-3203 KW - object recognition KW - wavelet transform KW - neural network KW - pattern matching KW - multiresolution approximation KW - image analysis ER - TY - JOUR TI - AFLP genetic maps of Eucalyptus globulus and E-tereticornis AU - Marques, CM AU - Araujo, JA AU - Ferreira, JG AU - Whetten, R AU - DM O'Malley, AU - Liu, BH AU - Sederoff, R T2 - THEORETICAL AND APPLIED GENETICS DA - 1998/5// PY - 1998/5// DO - 10.1007/s001220050795 VL - 96 IS - 6-7 SP - 727-737 SN - 1432-2242 KW - genetic map KW - linkage KW - Eucalyptus KW - AFLP marker ER - TY - JOUR TI - A complex optimal signal-processing algorithm for frequency-stepped CW data AU - Wu, SKM AU - Ybarra, GA AU - Alexander, WE T2 - IEEE TRANSACTIONS ON CIRCUITS AND SYSTEMS II-ANALOG AND DIGITAL SIGNAL PROCESSING AB - We derive a complex nonlinear optimal signal-processing algorithm for estimating target ranges from a set of frequency-stepped continuous wave (FSCW) measurements. It is a generalization of a prior optimization algorithm in that the reflection amplitudes are modeled as phasors rather than real-valued scalars. The algorithm solves this nonlinear problem by separating it into its linear and nonlinear parts. The amplitudes of the reflections are first optimized by solving a set of linear equations in the least-squares sense. A performance measure is then calculated and scanned to find its global minimum to yield a set of reflection amplitudes and time-delay estimates. We derive analytical expressions for the performance measure and for the effects of noise in the measurement data. Finally, we present experimental results to demonstrate the performance of our algorithm. DA - 1998/6// PY - 1998/6// DO - 10.1109/82.686697 VL - 45 IS - 6 SP - 754-757 SN - 1057-7130 KW - optimization KW - range resolution KW - target range estimation ER - TY - JOUR TI - Using stocking or harvesting to reverse period-doubling bifurcations in discrete population models AU - Selgrade, JF T2 - JOURNAL OF DIFFERENCE EQUATIONS AND APPLICATIONS AB - This study considers a general class of 2-dimensional, discrete population models where each per capita transition function (fitness) depends on a linear combination of the densities of the interacting populations. The fitness functions are either monotone decreasing functions (pioneer fitnesses) or one-humped functions (climax fitnesses). Four sets of necessary inequality conditions are derived which guarantee generically that an equilibrium loses stability through a period-doubling bifurcation with respect to the pioneer self-crowding parameter. A stocking or harvesting term which is proportional to the pioneer density is introduced into the system. Conditions are determined under which this stocking or harvesting will reverse the bifurcation and restabilize the equilibrium. A numerical example illustrates how pioneer stocking can be used to reverse a period-doubling cascade and to maintain the system at any attracting cycle along the cascade. DA - 1998/// PY - 1998/// DO - 10.1080/10236199808808135 VL - 4 IS - 2 SP - 163-183 SN - 1023-6198 KW - discrete models KW - period-doubling bifurcations and reversals KW - pioneer and climax populations ER - TY - JOUR TI - Use of simulation and bootstrap in information-based group sequential studies AU - Scharfstein, D. O. AU - Tsiatis, A. A. T2 - Statistics in Medicine AB - In this paper, we present an information-based design and monitoring procedure which applies to any type of model for any type of group sequential study provided there is a unique parameter of interest one can estimate efficiently. Simulation techniques are described to handle the design phase of this procedure. Since designs depend on potentially unreliable guesses of nuisance parameters, we propose a bootstrap method that uses the information available at the interim analysis times to generate projections and prediction intervals for the time at which the study will be fully powered. A monitoring board can use this information to decide whether a redesign of the trial is warranted. We also show how to use simulation to redesign studies in progress. We illustrate all of these techniques with data from AIDS Clinical Trial Group Protocol 021. DA - 1998/// PY - 1998/// DO - 10.1002/(SICI)1097-0258(19980115)17:1<75::AID-SIM731>3.0.CO;2-N VL - 17 IS - 1 SP - 75-87 ER - TY - JOUR TI - Theoretical and practical aspects of fiber length comparisons of various cottons AU - Cui, X. L. AU - Calamari, T. A. AU - Suh, M. W. T2 - Textile Research Journal AB - Fiber length is one of the most important physical properties of cotton. Frequently, it is necessary to compare the fiber lengths of various cottons. The commonly used statistical characteristics of a cotton fiber length distribution include the mean fiber length, short fiber content, and upper quartile length. These statistics may be calculated from number-based or weight-based distributions. This paper shows theoretically and experimentally that number-based and weight-based statistics may give opposite rank orders in some cases when they are used to compare cotton fiber lengths. DA - 1998/// PY - 1998/// DO - 10.1177/004051759806800701 VL - 68 IS - 7 SP - 467-472 ER - TY - JOUR TI - Statistical gymnastics AU - Quesenberry, C. P. T2 - Quality Progress DA - 1998/// PY - 1998/// VL - 31 IS - 9 SP - 77-79 ER - TY - JOUR TI - Software for mapping and analyzing weed distributions: gWeedMap AU - Krueger, DW AU - Coble, HD AU - Wilkerson, GG T2 - AGRONOMY JOURNAL AB - Abstract The spatial pattern of weeds in a field is often patchy. This pattern can be visualized with maps created by geographical information system (GIS) software. However, this software is often difficult to use and/or expensive, especially if not all of the GIS functionality is needed. The objective of this project was to develop a means of easily and economically generating weed maps. This was accomplished by creating a PC‐based Windows software tool to generate weed maps from scouting information. The scout enters weed data that has been collected in a gridded, systematic sampling protocol. From this information, the program creates a map for each weed species in the field. Scouting data can be density, percent cover, or any other type of measurement. Five data ranges are displayed on the map, with the user specifying the data values and map colors associated with each range. Various statistics are calculated, such as the average density of each species. Weed diversity in each field is determined with Shannon's diversity index and evenness index. These indices are also calculated with the density data weighted by the competitiveness of each weed species. This gives the weed ecologist a quantitative measure of the competitive diversity, which is related to the impact of the weed population on yield loss. DA - 1998/// PY - 1998/// DO - 10.2134/agronj1998.00021962009000040018x VL - 90 IS - 4 SP - 552-556 SN - 1435-0645 ER - TY - JOUR TI - Semiparametric efficient estimation in the generalized odds-rate class of regression models for right-censored time-to-event data AU - Scharfstein, D. O. AU - Tsiatis, A. A. AU - Gilbert, P. B. T2 - Lifetime Data Analysis DA - 1998/// PY - 1998/// DO - 10.1023/A:1009634103154 VL - 4 IS - 4 SP - 355-391 ER - TY - CHAP TI - Random coefficient regression AU - Gumpertz, M. L. AU - Pantula, S. G. T2 - Samuel Kotz (Editor-in-chief), Encyclopedia of statistical sciences CN - QA276.14 .E5 PY - 1998/// SP - 581-588 PB - New York: Wiley ER - TY - JOUR TI - On-line measurement of fabric bending behavior Part II: Effects of fabric nonlinear bending behavior AU - Zhou, N. Y. AU - ghosh, T2 - Textile Research Journal AB - A generalized fabric bending model is developed based on the nonlinear bending moment-curvature relationship of fabrics. This model makes it possible to theoretically investigate the effects of fabric nonlinear bending behavior on measured bending prop erty values. The dependence of measured parameters (e.g., bending length, bending rigidity) on the conditions for the cantilever and heart loop, loop 3, and loop 4 tests is determined theoretically. Calculated results show good agreement with experimental observations reported in the literature for the cantilever and heart loop. An important discovery in this investigation is that the bending length values calculated and measured from loop 3 and loop 4 are not influenced by fabric sample length if that length is beyond a certain critical value. DA - 1998/// PY - 1998/// DO - 10.1177/004051759806800711 VL - 68 IS - 7 SP - 533–542 ER - TY - JOUR TI - Heritability and resource allocation of aluminum tolerance derived from soybean PI 416937 AU - Bianchi-Hall, CM AU - Carter, TE AU - Rufty, TW AU - Arellano, C AU - Boerma, HR AU - Ashley, DA AU - Burton, JW T2 - CROP SCIENCE AB - AIuminum toxicity restricts soybean [Glycine max (L.) Merr.] yield included many growing areas. When correction of toxicity by management is impractical, an economically sound alternative is to develop AI tolerant cultivars. Heritability (h2) estimates for AI tolerance in hydroponics would aid in the efficient design of selection programs for cultivar development. Our objectives were to determine the h2 of AI tolerance in a F4-derived population using tap root extension in hydroponics culture as the indicator of tolerance. The 120 random F4-derived lines of sensitive ‘Young’ × tolerant PI 416937 were evaluated in the absence (NOAL) and presence (HIAL) of AI (2 μM AI3+ activity) by means of a split-plot design. AIuminum stress increased seedling tap root extension 3% in PI 416937 and decreased extension in Young 53%. Mean progeny performance decreased 31%. Analysis of variance revealed significant (P < 0.05) progeny and progeny × AI interaction effects, indicating heritable genetic variation for AI tolerance. The h2 under HIAL was moderate (0.57) on a single-replication basis and high (0.87) based upon five replicates, indicating the relative ease by which AI tolerance may be improved. Tolerance expressed as percent of control (PC) had a similar h2. Approximately 6% of the F4-derived progeny in this study were numerically similar to the parents for AI response under HIAL, suggesting that three to five genes may control AI tolerance and that a population size of 150 random inbred lines may be needed to assure full recovery of AI tolerance in the progeny of future breeding populations. Expected gain and risk avoidance analysis suggested that two or three replications are sufficient for initial screening of single seed descent (SSD) populations derived from the PI 416937 and that employment of this PI as a control enhances the ability of the breeder to discard inferior types during screening. Practical advice is presented to assist plant breeders in the efficient improvement of AI tolerance in soybean. DA - 1998/// PY - 1998/// DO - 10.2135/cropsci1998.0011183X003800020040x VL - 38 IS - 2 SP - 513-522 SN - 1435-0653 ER - TY - JOUR TI - Effects of ozone on reproduction of twospotted spider mite (Acari : Tetranychidae) on white clover AU - Hummel, RL AU - Brandenburg, RL AU - Heagle, AS AU - Arellano, C T2 - ENVIRONMENTAL ENTOMOLOGY AB - Twospotted spider mite, Tetranychus urticae Koch, is a significant pest of peanut, Arachis hypogeae L., that continues to present problems as an induced pest despite recent widespread implementation of IPM practices. Effects of ozone (O 3 ) on reproduction of twospotted spider mites feeding on an O 3 -sensitive clone and an O 3 -resistant clone of white clover, Trifolium repens L., were investigated in a greenhouse in continuous-stirred tank reactor chambers. Mite eggs of narrow age distribution (≍6 h) were placed on white clover plants exposed to 5 treatment levels of O 3 . Constant amounts of O 3 were added to charcoal-filtered air for 6 h per day to achieve 5 mean concentrations ranging from 10 to 112 nl per liter. Plants were exposed to O 3 ≍9 d before infestation with mites; daily exposures continued for ≍20 d after mite infestation. The developmental stage of each mite was recorded at ≍2-d intervals until females were sexually mature (≍10 d) and began ovipositing. Thereafter, the cumulative number of eggs produced per mite was recorded. After ≍5 d of oviposition, each adult mite was removed and the percentage hatch of eggs remaining on each plant was measured for an additional 5 d. Ozone caused more chlorosis and necrosis on the O 3 -sensitive clover clone than on the O 3 -resistant clover clone. Increasing O 3 levels caused a significant linear decrease in developmental period of the mites. Estimates of time to 1st oviposition decreased linearly with increasing O 3 . Estimates of time of 1st hatch of 2nd-generation eggs decreased linearly with increasing O 3 . Elevated O 3 levels appear to decrease the time required for female mites to develop from egg to ovipositing adult, which may have a profound effect on the intrinsic rate of population increase. Different responses by mites feeding on resistant plants versus susceptible plants suggests that this is a plant-mediated response. DA - 1998/4// PY - 1998/4// DO - 10.1093/ee/27.2.388 VL - 27 IS - 2 SP - 388-394 SN - 1938-2936 KW - Tetranychus urticae KW - ozone KW - air pollution KW - white clover KW - peanut ER - TY - JOUR TI - Drug concentration heterogeneity facilitates the evolution of drug resistance AU - Kepler, TB AU - Perelson, AS T2 - PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA AB - Pathogenic microorganisms use Darwinian processes to circumvent attempts at their control through chemotherapy. In the case of HIV-1 infection, in which drug resistance is a continuing problem, we show that in one-compartment systems, there is a relatively narrow window of drug concentrations that allows evolution of resistant variants. When the system is enlarged to two spatially distinct compartments held at different drug concentrations with transport of virus between them, the range of average drug concentrations that allow evolution of resistance is significantly increased. For high average drug concentrations, resistance is very unlikely to arise without spatial heterogeneity. We argue that a quantitative understanding of the role played by heterogeneity in drug levels and pathogen transport is crucial for attempts to control re-emergent infectious disease. DA - 1998/9/29/ PY - 1998/9/29/ DO - 10.1073/pnas.95.20.11514 VL - 95 IS - 20 SP - 11514-11519 SN - 0027-8424 KW - sanctuary sites KW - HIV ER - TY - JOUR TI - Dietary fibre composition in developing apple fruits AU - Gheyas, F AU - Blankenship, SM AU - Young, E AU - McFeeters, R T2 - JOURNAL OF HORTICULTURAL SCIENCE & BIOTECHNOLOGY AB - SummaryChanges in dietary fibre composition of ‘Delicious’, ‘Golden Delicious’, and ‘Stayman’ apples were studied over the course of fruit development. Fruit were analysed every 15 d starting 30 d after full bloom (DAFB) up to 150 DAFB in ‘Delicious’, 135 DAFB in ‘Golden Delicious’, and 120 DAFB in ‘Stayman’. Nonstarch cell wall materials (NSCWM) and nonstarch polysaccharides (NSP) content of apple flesh of all the cultivars decreased during development. During the period between 30 DAFB and 120 DAFB, NSP content of ‘Delicious’, ‘Golden Delicious’, and ‘Stayman’ fruit decreased by 25.2%, 29.0%, and 19.3%, respectively. Relative amount of monosaccharides present in apple fibre also changed during development. Proportions of rhamnose, arabinose, mannose, and galactose decreased during development while the proportions of xylose, glucose and uronic acid increased. Firmness of apple flesh was positively correlated with its NSP content. Firmness was also strongly correlated with the amounts of galactose, glucose, arabinose, mannose, and rhamnose present in the hydrolyzates of apple fibre. DA - 1998/9// PY - 1998/9// DO - 10.1080/14620316.1998.11511026 VL - 73 IS - 5 SP - 631-639 SN - 0022-1589 ER - TY - JOUR TI - Utility of SSRs for determining genetic similarities and relationships in maize using an agarose gel system AU - Senior, ML AU - Murphy, JP AU - Goodman, MM AU - Stuber, CW T2 - CROP SCIENCE AB - Among maize ( Zea maize L.) breeders, there is a heightened awareness of the necessity for both maintaining genetic diversity for crop improvement and improving the quality of genetic resource management. Restriction fragment length polymorphisms (RFLPs) and isozymes can serve as genetic markers for estimating divergence or diversity; however, the limited number of polymorphic isozyme loci available and the labor intensive and time consuming nature of RFLPs make their use for this purpose prohibitive. Simple sequence repeats (SSRs), when resolved using agarose gels, may be a viable and costeffective alternative to RFLPs and isozymes. Ninety‐four elite maize inbred lines, representative of the genetic diversity among lines derived from the Corn Belt Dent and Southern Dent maize races, were assayed for polymorphism at 70 SSR marker loci using agarose gels. The 365 alleles identified served as raw data for estimating genetic similarities among these lines. The patterns of genetic divergence revealed by the SSR polymorphisms were consistent with known pedigrees. A cluster analysis placed the inbred lines in nine clusters that correspond to major heterotic groups or market classes for North American maize. A unique fingerprint for each inbred line could be obtained from as few as five SSR loci. The utility of polymerase chain reaction (PCR)‐based markers such as SSRs for measuring genetic diversity, for assigning lines to heterotic groups and for genetic fingerprinting equals or exceeds that of RFLP markers, a property that may prove a valuable asset for a maize breeding program. DA - 1998/// PY - 1998/// DO - 10.2135/cropsci1998.0011183X003800040034x VL - 38 IS - 4 SP - 1088-1098 SN - 0011-183X ER - TY - JOUR TI - Generating multiple imputations for matrix sampling data analyzed with item response models AU - Thomas, N. AU - Gan, N. T2 - Journal of Educational and Behavioral Statistics AB - Sample survey designs in which each participant is administered a subset of the items contained in a complete survey instrument are becoming an increasingly popular method of reducing respondent burden ( Mislevy, Beaton, Kaplan, Sheehan 1992 ; Raghunathan & Grizzle, 1995 ; Wacholder, Carroll, Pee, Gail 1994 ). Data from these survey designs can be analyzed using multiple imputation methodology that generates several imputed values for the missing data and thus yields several complete data sets. These data sets are then analyzed using complete data estimators and their standard errors ( Rubin, 1987b ). Generating the imputed data sets, however, can be very difficult. We describe improvements to the methods currently used to generate the imputed data sets for item response models summarizing educational data collected by the National Assessment of Educational Progress (NAEP), an ongoing collection of samples of 4th, 8th, and 12th grade students in the United States. The improved approximations produce small to moderate changes in commonly reported estimates, with the larger changes associated with an increasing amount of missing data. The improved approximations produce larger standard errors. DA - 1998/// PY - 1998/// DO - 10.3102/10769986022004425 VL - 22 IS - 4 SP - 425-445 ER - TY - BOOK TI - Cornelius Lanczos: Collected published papers with commentaries AU - Davis, W. R. AU - Chu, M. T. AU - McConnell, J. R. AU - Dolan, P. AU - Norris, L. K. AU - Ortiz, E. AU - Plemmon, R. J. AU - Ridgeway, D. AU - Scaife, B.K.P. AU - Stewart, W. J. AU - York, J. W. AU - Doggett, W. O. AU - Gellai, B. M. AU - Gsponer, A. A. AU - Prioli, C. A. CN - QC19.3 .L363 1998 DA - 1998/// PY - 1998/// PB - Raleigh, NC: College of Physical and Mathematical Sciences, North Carolina State University SN - 0929493003 ER - TY - JOUR TI - Computer simulation of inspiratory nasal airflow and inhaled gas uptake in a rhesus monkey AU - Kepler, GM AU - Richardson, RB AU - Morgan, KT AU - Kimbell, JS T2 - TOXICOLOGY AND APPLIED PHARMACOLOGY AB - There is increasing evidence that inspiratory airflow patterns play a major role in determining the location of nasal lesions induced in rats by reactive, water-soluble gases such as formaldehyde and chlorine. Characteristic lesion patterns have also been seen in inhalation toxicity studies conducted in rhesus monkeys, the nasal anatomy of which resembles that of humans. To examine the hypothesis that regions of high airflow-dependent uptake and lesions occur in similar nasal locations in the primate, airflow and gas uptake patterns were simulated in an anatomically accurate computer model of the right nasal airway of a rhesus monkey. The results of finite-element simulations of steady-state inspiratory nasal airflow for the full range of resting physiological flow rates are reported. Simulated airflow patterns agreed well with experimental observations, exhibiting secondary flows in the anterior nose and streamlined flow posteriorly. Simulated airflow results were used to predict gas transport to the nasal passage walls using formaldehyde as an example compound. Results from the uptake simulations were compared with published observations of formaldehyde-induced nasal lesions in rhesus monkeys and indicated a strong correspondence between airflow-dependent transport patterns and local lesion sites. This rhesus computer model will provide a means for confirming the extrapolation of toxicity data between species by extrapolating rat simulation results to monkeys and comparing these predictions with primate lesion data. DA - 1998/5// PY - 1998/5// DO - 10.1006/taap.1997.8350 VL - 150 IS - 1 SP - 1-11 SN - 0041-008X ER - TY - JOUR TI - Assessing the impact of secondary structure and solvent accessibility on protein evolution AU - Goldman, N. AU - Thorne, J. L. AU - Jones, D. T. T2 - Genetics DA - 1998/// PY - 1998/// VL - 149 IS - 1 SP - 445-458 ER - TY - JOUR TI - A dispersion model for the hepatic uptake and elimination of 2,3,7,8-tetrachlorodibenzo-p-dioxin AU - Banks, HT AU - Musante, CJ AU - Tran, HT T2 - MATHEMATICAL AND COMPUTER MODELLING AB - A convection-dispersion model for the uptake and elimination of 2,3,7,8-tetrachlorodibenzo- p -dioxin (TCDD) in the liver is presented. The model is adapted from the general dispersion model of Roberts and Rowland and includes the dynamics of TCDD interaction with two intracellular proteins, the Ah receptor and cytochrome P450 IA2. A “well-mixed” compartment was added to describe the venous blood concentration of TCDD. The result is a nonlinear system of seven coupled partial and ordinary differential equations with time delays. DA - 1998/7// PY - 1998/7// DO - 10.1016/S0895-7177(98)00077-6 VL - 28 IS - 1 SP - 9-29 SN - 0895-7177 KW - physiologically-based pharmacokinetic (PBPK) model KW - 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) KW - liver transport models KW - nonlinear partial differential equations KW - delay equations ER - TY - JOUR TI - Marginal curvatures for functions of parameters in nonlinear regression AU - Kang, G. AU - Rawlings, J. O. T2 - Statistica Sinica DA - 1998/// PY - 1998/// VL - 8 IS - 2 SP - 467-476 ER - TY - JOUR TI - Ground-based infrared solar spectroscopic measurements of carbon monoxide during 1994 Measurement of Air Pollution From Space flights AU - Pougatchev, NS AU - Jones, NB AU - Connor, BJ AU - Rinsland, CP AU - Becker, E AU - Coffey, MT AU - Connors, VS AU - Demoulin, P AU - Dzhola, AV AU - Fast, H AU - Grechko, EI AU - Hannigan, JW AU - Koike, M AU - Kondo, Y AU - Mahieu, E AU - Mankin, WG AU - Mittermeier, RL AU - Notholt, J AU - Reichle, HG AU - Sen, B AU - Steele, LP AU - Toon, GC AU - Yurganov, LN AU - Zander, R AU - Zhao, Y T2 - JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES AB - Results of the comparison of carbon monoxide ground‐based infrared solar spectroscopic measurements with data obtained during 1994 Measurement of Air Pollution From Space (MAPS) flights are presented. Spectroscopic measurements were performed correlatively with April and October MAPS flights by nine research groups from Belgium, Canada, Germany, Japan, New Zealand, Russia, and the United States. Characterization of the techniques and error analysis were performed. The role of the CO a priori profile used in the retrieval was estimated. In most cases an agreement between spectroscopic and MAPS data is within estimated MAPS accuracy of ±10%. DA - 1998/8/20/ PY - 1998/8/20/ DO - 10.1029/97JD02889 VL - 103 IS - D15 SP - 19317-19325 SN - 2169-897X ER - TY - JOUR TI - Estimation of fishing and natural mortality from tagging studies an fisheries with two user groups AU - Brooks, EN AU - Pollock, KH AU - Hoenig, JM AU - Hearn, WS T2 - CANADIAN JOURNAL OF FISHERIES AND AQUATIC SCIENCES AB - We present generalizations of fishery models that allow for the separate estimation of fishing mortality when more than one user group is present (e.g., a commercial and a recreational fishery). This model also allows for the fisheries to be in operation for any length of time whereas previously fisheries were generally considered to be pulse or continuous. Three cases are considered: (i) fisheries operate consecutively, (ii) fisheries overlap for a part of their seasons, and (iii) fisheries are in operation for the whole year. The results of a simulation study are included, which provide estimates of fishing and natural mortality along with their proportional standard errors (CVs). All scenarios had good precision, with most CVs < 25% and usually very little difference between the three cases. Coefficients of interaction, the potential gain by one fishery if another is closed down, are also given along with a method for calculating them. Factors affecting these coefficients of interaction were the order in which fisheries operated, amount of overlap in fishing seasons, and intensity of fishing effort by each fishery. We believe that these models could provide useful information for the management of fisheries with multiple user groups where allocation conflicts may arise. DA - 1998/9// PY - 1998/9// DO - 10.1139/cjfas-55-9-2001 VL - 55 IS - 9 SP - 2001-2010 SN - 1205-7533 ER - TY - JOUR TI - Estimating rates of local species extinction, colonization, and turnover in animal communities AU - Nichols, J. D. AU - Boulinier, T. AU - Hines, J. E. AU - Pollock, K. H. AU - Sauer, J. R. T2 - Ecological Applications DA - 1998/// PY - 1998/// DO - 10.2307/2640974 VL - 8 IS - 4 SP - 1213-1225 ER - TY - JOUR TI - Detecting marker-disease association by testing for Hardy-Weinberg disequilibrium at a marker locus AU - Nielsen, DM AU - Ehm, MG AU - Weir, BS T2 - AMERICAN JOURNAL OF HUMAN GENETICS AB - We review and extend a recent suggestion that fine-scale localization of a disease-susceptibility locus for a complex disease be done on the basis of deviations from Hardy-Weinberg equilibrium among affected individuals. This deviation is driven by linkage disequilibrium between disease and marker loci in the whole population and requires a heterogeneous genetic basis for the disease. A finding of marker-locus Hardy-Weinberg disequilibrium therefore implies disease heterogeneity and marker-disease linkage disequilibrium. Although a lack of departure of Hardy-Weinberg disequilibrium at marker loci implies that disease susceptibilityweighted linkage disequilibria are zero, given disease heterogeneity, it does not follow that the usual measures of linkage disequilibrium are zero. For disease-susceptibility loci with more than two alleles, therefore, care is needed in the drawing of inferences from marker Hardy-Weinberg disequilibria. DA - 1998/11// PY - 1998/11// DO - 10.1086/302114 VL - 63 IS - 5 SP - 1531-1540 SN - 0002-9297 ER - TY - JOUR TI - Density-dependent prenatal androgen exposure as an endogenous mechanism for the generation of cycles in small mammal populations AU - Cowell, LG AU - Crowder, LB AU - Kepler, TB T2 - JOURNAL OF THEORETICAL BIOLOGY AB - Small mammal populations exhibit cyclic fluctuations in their population densities. Several hypotheses regarding the mechanisms underlying these population cycles have been advanced, but none has yet gained general approval. We propose here an endogenous mechanism based on the masculinization of female offspring in response to increased population levels. High population levels trigger the non-specific stress response resulting in high levels of circulating androgens in individuals of the population, including pregnant females. These androgens masculinize female offspring in utero, thereby reducing the reproductive capacity of the next generation and subsequently the population size. We have developed and analysed a mathematical model to investigate the possible role of prenatal androgen exposure in the generation of limit cycles. We find the locus of Hopf bifurcations for this model and show that limit cycles depend on three parameters: (1) the delay between birth and sexual maturation; (2) the slope of the function that relates average prenatal androgen exposure to total population density; and (3) the difference between the maximum birth rates of the low- and high-androgen exposed females. We derive the analytical form relating these parameters at the Hopf-bifurcation locus and discuss its biological ramifications. In brief, in each of these three parameters is sufficiently large, population cycles will results from the endogenous mechanism proposed.Copyright 1998 Academic Press Limited Copyright 1998 Academic Press Limited DA - 1998/1/7/ PY - 1998/1/7/ DO - 10.1006/jtbi.1997.0543 VL - 190 IS - 1 SP - 93-106 SN - 1095-8541 ER - TY - JOUR TI - A comparative study of sibship tests of linkage and/or association AU - Monks, SA AU - Kaplan, NL AU - Weir, BS T2 - AMERICAN JOURNAL OF HUMAN GENETICS AB - Population-based tests of association have used data from either case-control studies or studies based on trios (affected child and parents). Case-control studies are more prone to false-positive results caused by inappropriate controls, which can occur if, for example, there is population admixture or stratification. An advantage of family-based tests is that cases and controls are well matched, but parental data may not always be available, especially for late-onset diseases. Three recent family-based tests of association and linkage utilize unaffected siblings as surrogates for untyped parents. In this paper, we propose an extension of one of these tests. We describe and compare the four tests in the context of a complex disease for both biallelic and multiallelic markers, as well as for sibships of different sizes. We also examine the consequences of having some parental data in the sample. DA - 1998/11// PY - 1998/11// DO - 10.1086/302104 VL - 63 IS - 5 SP - 1507-1516 SN - 0002-9297 ER - TY - JOUR TI - Molecular evolution of the Myb family of transcription factors: Evidence for polyphyletic origin AU - Rosinski, JA AU - Atchley, WR T2 - JOURNAL OF MOLECULAR EVOLUTION DA - 1998/1// PY - 1998/1// DO - 10.1007/PL00006285 VL - 46 IS - 1 SP - 74-83 SN - 1432-1432 KW - Myb KW - evolution KW - phylogeny KW - transcription factors KW - oncogene ER - TY - JOUR TI - Jetlet formation from diabatic forcing with applications to the 1994 Palm Sunday tornado outbreak AU - Hamilton, DW AU - Lin, YL AU - Weglarz, RP AU - Kaplan, ML T2 - MONTHLY WEATHER REVIEW AB - The three-dimensional responses of simple stably stratified barotropic and baroclinic flows to prescribed diabatic forcing are investigated using a dry, hydrostatic, primitive equation numerical model (the North Carolina State University Geophysical Fluid Dynamics Model). A time-dependent diabatic forcing is utilized to isolate the effects of latent heat release in a midlatitude convective system. Examination of the mass-momentum adjustments to the diabatic forcing is performed with a focus on the development of an isolated midlevel wind maximum. The results of both cases suggest the formation of a midlevel wind maximum in the form of a perturbation meso-β-scale cyclone, which later propagates downstream as the heating is decreased. The scale of the perturbation cyclone remains at a sub-Rossby radius of deformation length scale. Therefore, the mass perturbations adjust to the wind perturbations as the mesocyclone propagates downstream. Transverse vertical circulations, which favor ascent on the right flank of the wind maximum, appear to be attributed to compensatory gravity wave motions, initially triggered by the thermal forcing, which laterally disperses as the heating is reduced. The simple model simulations are used to explain more complex results from a previous mesoscale modeling study (the Mesoscale Atmospheric Simulation System, MASS), in which it was hypothesized that an upstream mesoscale convective complex triggered a midlevel jetlet through geostrophic adjustment of the wind to the latent heat source. The MASS simulated jetlet attained a transverse vertical circulation that favored ascent on the right flank of the midlevel jetlet. The jetlet and accompanying transverse vertical circulations later propagated downstream aiding in the formation of the 27–28 March 1994 tornadic environment in Alabama and Georgia. DA - 1998/8// PY - 1998/8// DO - 10.1175/1520-0493(1998)126<2061:JFFDFW>2.0.CO;2 VL - 126 IS - 8 SP - 2061-2089 SN - 0027-0644 ER - TY - JOUR TI - A new device design methodology for manufacturability AU - Lu, JC AU - Holton, WC AU - Fenner, JS AU - Williams, SC AU - Kim, KW AU - Hartford, AH AU - Chen, D AU - Roze, K AU - Littlejohn, MA T2 - IEEE TRANSACTIONS ON ELECTRON DEVICES AB - As future technology generations for integrated circuits continue to "shrink", TCAD tools must be made more central to manufacturing issues; thus, yield optimization and design for manufacturing (DFM) should be addressed integrally with performance and reliability when using TCAD during the initial product design. This paper defines the goals for DFM in TCAD simulations and outlines a formal procedure for achieving an optimized result (ODFM). New design of experiments (DOE), weighted least squares modeling and multiple-objective mean-variance optimization methods are developed as significant parts of the new ODFM procedure. Examples of designing a 0.18-/spl mu/m MOSFET device are given to show the impact of device design procedures on device performance distributions and sensitivity variance profiles. DA - 1998/3// PY - 1998/3// DO - 10.1109/16.661225 VL - 45 IS - 3 SP - 634-642 SN - 0018-9383 ER - TY - JOUR TI - Spatio-temporal modeling of residential sales data AU - Gelfand, AE AU - Ghosh, SK AU - Knight, , JR AU - Sirmans, CF T2 - JOURNAL OF BUSINESS & ECONOMIC STATISTICS DA - 1998/7// PY - 1998/7// DO - 10.2307/1392507 VL - 16 IS - 3 SP - 312-321 SN - 1537-2707 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-0032352145&partnerID=MN8TOARS KW - conditional autoregressive priors KW - forecasting KW - hedonic price model KW - hierarchical models KW - model choice KW - model validation KW - sampling-based fitting ER - TY - JOUR TI - Real-time monitoring of steady-state pulsed chemical beam epitaxy by p-polarized reflectance AU - Bachmann, KJ AU - Sukidi, N AU - Hopfner, C AU - Harris, C AU - Dietz, N AU - Tran, HT AU - Beeler, S AU - Ito, K AU - Banks, HT T2 - JOURNAL OF CRYSTAL GROWTH AB - The structure in the p-polarized reflectance (PR) intensity Rp4(t) - observed under conditions of pulsed chemical beam epitaxy (PCBE) - is modeled on the basis of the four-layer stack: ambient/surface reaction layer (SRL)/epilayer/substrate. Linearization of the PR intensity with regard to the phase factor associated with the SRL results in a good approximation that can be expressed as Rp4 = Rp3 + ΔRp.Rp3 is the reflectivity of the three-layer stack ambient-epilayer-substrate. ΔRp describes the properties of the SRL. An explicit relation is derived between ΔRp(t) and the time-dependent surface concentrations ch(t) (h = 1, 2, …, N) of the constituents of the SRL, which holds for conditions of submonolayer coverage of the surface by source vapor molecules. Under conditions of low temperature PCBE at high flux, the SRL is expected to exhibit nonideal behavior, mandating replacement of the surface concentrations by activities. Also, in this case, the thickness of the SRL must be represented in terms of partial molar volumina Vh. Since the relation between ΔRp(t) and the activities of reactants, intermediates and products of the chemical reactions driving heteroepitaxial growth is non-linear, the extraction of kinetic parameters from the measured time dependence of the PR signal generally requires numerical modeling. DA - 1998/1// PY - 1998/1// DO - 10.1016/s0022-0248(97)00410-7 VL - 183 IS - 3 SP - 323-337 SN - 0022-0248 KW - p-polarized reflectance KW - surface kinetics KW - chemical beam epitaxy KW - real-time process monitoring ER - TY - JOUR TI - Model choice: A minimum posterior predictive loss approach AU - Gelfand, A.E. AU - Ghosh, S.K. T2 - Biometrika AB - Journal Article Model choice: A minimum posterior predictive loss approach Get access ALAN E. GELFAND, ALAN E. GELFAND Department of Statistics, University of ConnecticutStorrs, Connecticut 06269-3120, U.S.A.alan@stat.uconn.edu Search for other works by this author on: Oxford Academic Google Scholar SUJIT K. GHOSH SUJIT K. GHOSH Department of Statistics, North Carolina State UniversityRaleigh, North Carolina, 27695-8203, U.S.A.sghosh@stat.ncsu.edu Search for other works by this author on: Oxford Academic Google Scholar Biometrika, Volume 85, Issue 1, March 1998, Pages 1–11, https://doi.org/10.1093/biomet/85.1.1 Published: 01 March 1998 Article history Received: 01 September 1995 Revision received: 01 June 1997 Published: 01 March 1998 DA - 1998/// PY - 1998/// DO - 10.1093/biomet/85.1.1 VL - 85 IS - 1 SP - 1-11 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-0002799511&partnerID=MN8TOARS ER - TY - JOUR TI - Marker selection for the transmission/disequilibrium test, in recently admixed populations AU - Kaplan, NL AU - Martin, ER AU - Morris, RW AU - Weir, BS T2 - AMERICAN JOURNAL OF HUMAN GENETICS AB - SummaryRecent admixture between genetically differentiated populations can result in high levels of association between alleles at loci that are ≤10 cM apart. The transmission/disequilibrium test (TDT) proposed by Spielman et al., 1993Spielman RS McGinnis RE Ewens WJ Transmission test for linkage disequilibrium: the insulin gene region and insulin-dependent diabetes mellitus (IDDM).Am J Hum Genet. 1993; 52: 506-516PubMed Google Scholar can be a powerful test of linkage between disease and marker loci in the presence of association and therefore could be a useful test of linkage in admixed populations. The degree of association between alleles at two loci depends on the differences in allele frequencies, at the two loci, in the founding populations; therefore, the choice of marker is important. For a multiallelic marker, one strategy that may improve the power of the TDT is to group marker alleles within a locus, on the basis of information about the founding populations and the admixed population, thereby collapsing the marker into one with fewer alleles. We have examined the consequences of collapsing a microsatellite into a two-allele marker, when two founding populations are assumed for the admixed population, and have found that if there is random mating in the admixed population, then typically there is a collapsing for which the power of the TDT is greater than that for the original microsatellite marker. A method is presented for finding the optimal collapsing that has minimal dependence on the disease and that uses estimates either of marker allele frequencies in the two founding populations or of marker allele frequencies in the current, admixed population and in one of the founding populations. Furthermore, this optimal collapsing is not always the collapsing with the largest difference in allele frequencies in the founding populations. To demonstrate this strategy, we considered a recent data set, published previously, that provides frequency estimates for 30 microsatellites in 13 populations. Recent admixture between genetically differentiated populations can result in high levels of association between alleles at loci that are ≤10 cM apart. The transmission/disequilibrium test (TDT) proposed by Spielman et al., 1993Spielman RS McGinnis RE Ewens WJ Transmission test for linkage disequilibrium: the insulin gene region and insulin-dependent diabetes mellitus (IDDM).Am J Hum Genet. 1993; 52: 506-516PubMed Google Scholar can be a powerful test of linkage between disease and marker loci in the presence of association and therefore could be a useful test of linkage in admixed populations. The degree of association between alleles at two loci depends on the differences in allele frequencies, at the two loci, in the founding populations; therefore, the choice of marker is important. For a multiallelic marker, one strategy that may improve the power of the TDT is to group marker alleles within a locus, on the basis of information about the founding populations and the admixed population, thereby collapsing the marker into one with fewer alleles. We have examined the consequences of collapsing a microsatellite into a two-allele marker, when two founding populations are assumed for the admixed population, and have found that if there is random mating in the admixed population, then typically there is a collapsing for which the power of the TDT is greater than that for the original microsatellite marker. A method is presented for finding the optimal collapsing that has minimal dependence on the disease and that uses estimates either of marker allele frequencies in the two founding populations or of marker allele frequencies in the current, admixed population and in one of the founding populations. Furthermore, this optimal collapsing is not always the collapsing with the largest difference in allele frequencies in the founding populations. To demonstrate this strategy, we considered a recent data set, published previously, that provides frequency estimates for 30 microsatellites in 13 populations. DA - 1998/3// PY - 1998/3// DO - 10.1086/301760 VL - 62 IS - 3 SP - 703-712 SN - 0002-9297 ER - TY - JOUR TI - Investigations of the problems of assessing aflatoxin levels in peanuts AU - Giesbrecht, FG AU - Whitaker, TB T2 - BIOMETRICS AB - In this study, a number of probability distributions that have been used to model the occurrence of aflatoxin in peanuts are compared. Two distributions, the compound gamma and the negative binomial, are shown to have special appeal in that both can be justified by reasoning from the fundamental biological and stochastic processes that generate the aflatoxin. Since method of moments and maximum likelihood give consistent estimates of parameters in both models, practical considerations suggest using the former. One hundred twenty data sets, each consisting of fifty observations, were not sufficient to provide goodness-of-fit tests to establish either as superior to the other as a model. Both models fit the data well, appreciably better than other models examined. An attractive aspect of the compound gamma and the negative binomial distributions is that, as a consequence of their theoretical underpinnings, both involve parameters that have meaningful interpretations. In the compound gamma, the alpha parameter reflects the shape of the kernel-to-kernel aflatoxin content distribution, the lambda parameter reflects the number (or frequency) of contaminated kernels in the sample, and the beta parameter is a scale parameter. In the negative binomial, the two parameters can be used as measures of mean or location and shape. DA - 1998/6// PY - 1998/6// DO - 10.2307/3109780 VL - 54 IS - 2 SP - 739-753 SN - 0006-341X KW - aflatoxin concentration KW - compound gamma KW - modeling KW - negative binomial ER - TY - JOUR TI - Interlocus association of allozyme genotypes in settlements of scallop Mizuhopecten (Patinopecten) in coastal waters of Primorye AU - Pudovkin, A. I. AU - Zaykin, D. V. AU - Dolganov, S. M. T2 - Genetika DA - 1998/// PY - 1998/// VL - 34 IS - 3 SP - 385-392 ER - TY - JOUR TI - Higher temporal variability of forest breeding bird communities in fragmented landscapes AU - Boulinier, T AU - Nichols, JD AU - Hines, JE AU - Sauer, , JR AU - Flather, CH AU - Pollock, KH T2 - PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA AB - Understanding the relationship between animal community dynamics and landscape structure has become a priority for biodiversity conservation. In particular, predicting the effects of habitat destruction that confine species to networks of small patches is an important prerequisite to conservation plan development. Theoretical models that predict the occurrence of species in fragmented landscapes, and relationships between stability and diversity do exist. However, reliable empirical investigations of the dynamics of biodiversity have been prevented by differences in species detection probabilities among landscapes. Using long-term data sampled at a large spatial scale in conjunction with a capture-recapture approach, we developed estimates of parameters of community changes over a 22-year period for forest breeding birds in selected areas of the eastern United States. We show that forest fragmentation was associated not only with a reduced number of forest bird species, but also with increased temporal variability in the number of species. This higher temporal variability was associated with higher local extinction and turnover rates. These results have major conservation implications. Moreover, the approach used provides a practical tool for the study of the dynamics of biodiversity. DA - 1998/6/23/ PY - 1998/6/23/ DO - 10.1073/pnas.95.13.7497 VL - 95 IS - 13 SP - 7497-7501 SN - 0027-8424 ER - TY - JOUR TI - A mean field annealing approach to robust corner detection AU - Sohn, K AU - Kim, JH AU - Alexander, WE T2 - IEEE TRANSACTIONS ON SYSTEMS MAN AND CYBERNETICS PART B-CYBERNETICS AB - This paper is an extension of our previous paper to improve the capability of detecting corners. We proposed a method of boundary smoothing for curvature estimation using a constrained regularization technique in the previous paper. We propose another approach to boundary smoothing for curvature estimation in this paper to improve the capability of detecting corners. The method is based on a minimization strategy known as mean field annealing which is a deterministic approximation to simulated annealing. It removes the noise while preserving corners very well. Thus, we can detect corners easier and better in this approach than in the constrained regularization approach. Finally, some matching results based on the corners detected by corner sharpness in the mean field annealing approach are presented as a demonstration of the power of the proposed algorithm. DA - 1998/2// PY - 1998/2// DO - 10.1109/3477.658581 VL - 28 IS - 1 SP - 82-90 SN - 1083-4419 ER - TY - JOUR TI - The effect of serial dilution error on calibration inference in immunoassay AU - Higgins, KM AU - Davidian, M AU - Chew, G AU - Burge, H T2 - BIOMETRICS AB - A common practice in immunoassay is the use of sequential dilutions of an initial stock solution of the antigen of interest to obtain standard samples in a desired concentration range. Nonlinear, heteroscedastic regression models are a common framework for analysis, and the usual methods for fitting the model assume that measured responses on the standards are independent. However, the dilution procedure introduces a propagation of random measurement error that may invalidate this assumption. We demonstrate that failure to account for serial dilution error in calibration inference on unknown samples leads to serious inaccuracy of assessments of assay precision such as confidence intervals and precision profiles. Techniques for taking serial dilution error into account based on data from multiple assay runs are discussed and are shown to yield valid calibration inferences. DA - 1998/3// PY - 1998/3// DO - 10.2307/2533992 VL - 54 IS - 1 SP - 19-32 SN - 0006-341X KW - confidence intervals KW - ELISA KW - generalized least squares KW - measurement error KW - precision profile KW - variance function estimation ER - TY - JOUR TI - The distribution of variation in regulatory gene segments, as present in MHC class II promoters AU - Cowell, LG AU - Kepler, TB AU - Janitz, M AU - Lauster, R AU - Mitchison, NA T2 - GENOME RESEARCH AB - Diversity in the antigen-binding receptors of the immune system has long been a primary interest of biologists. Recently it has been suggested that polymorphism in regulatory (noncoding) gene segments is of substantial importance as well. Here, we survey the level of variation in MHC class II gene promoters in man and mouse using extensive collections of published sequences together with unpublished sequences recently deposited by us in the EMBL gene bank using the Shannon entropy to quantify diversity. For comparison, we also apply our analysis to distantly related MHC class II promoters, as well as to class I promoters and to class II coding regions. We observe a high level of intraspecies variability, which in mouse but not in man is localized to a significant extent near the binding sites of transcription factors-sites that are conserved over longer evolutionary distances. This localization may both indicate and enhance heterozygote advantage, as the presence of two functionally different promoters would be expected to confer flexibility in the immune response. DA - 1998/2// PY - 1998/2// DO - 10.1101/gr.8.2.124 VL - 8 IS - 2 SP - 124-134 SN - 1549-5469 ER - TY - JOUR TI - Pre- and post-season tagging models: estimation of reporting rate and fishing and natural mortality rates AU - Hearn, WS AU - Pollock, KH AU - Brooks, EN T2 - CANADIAN JOURNAL OF FISHERIES AND AQUATIC SCIENCES DA - 1998/1// PY - 1998/1// DO - 10.1139/cjfas-55-1-199 VL - 55 IS - 1 SP - 199-205 SN - 1205-7533 ER - TY - JOUR TI - Noise and nonlinearity in measles epidemics: Combining mechanistic and statistical approaches to population modeling AU - Ellner, SP AU - Bailey, BA AU - Bobashev, GV AU - Gallant, AR AU - Grenfell, BT AU - Nychka, DW T2 - AMERICAN NATURALIST AB - We present and evaluate an approach to analyzing population dynamics data using semimechanistic models. These models incorporate reliable information on population structure and underlying dynamic mechanisms but use nonparametric surface‐fitting methods to avoid unsupported assumptions about the precise form of rate equations. Using historical data on measles epidemics as a case study, we show how this approach can lead to better forecasts, better characterizations of the dynamics, and a better understanding of the factors causing complex population dynamics relative to either mechanistic models or purely descriptive statistical time‐series models. The semimechanistic models are found to have better forecasting accuracy than either of the model types used in previous analyses when tested on data not used to fit the models. The dynamics are characterized as being both nonlinear and noisy, and the global dynamics are clustered very tightly near the border of stability (dominant Lyapunov exponent λ ≈ 0). However, locally in state space the dynamics oscillate between strong short‐term stability and strong short‐term chaos (i.e., between negative and positive local Lyapunov exponents). There is statistically significant evidence for short‐term chaos in all data sets examined. Thus the nonlinearity in these systems is characterized by the variance over state space in local measures of chaos versus stability rather than a single summary measure of the overall dynamics as either chaotic or nonchaotic. DA - 1998/5// PY - 1998/5// DO - 10.1086/286130 VL - 151 IS - 5 SP - 425-440 SN - 1537-5323 KW - population dynamics KW - modeling KW - measles KW - time-series analysis KW - local Lyapunov exponents ER - TY - JOUR TI - Ground-based and airborne observations of carbon monoxide during NASA measurements of air pollution from satellite (MAPS) missions SRL-1 and SRL-2 AU - Doddridge, BG AU - Morales-Morales, R AU - Rhoads, KP AU - Merrill, JT AU - Novelli, PC AU - Dickerson, RR AU - Connors, VS AU - Reichle, HG T2 - JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES AB - Surface carbon monoxide (CO) data were acquired continuously at Heimaey, Iceland (63°24′N, 20° 18′W), Mace Head, Ireland (53° 19′N, 9°54′W), and Ragged Point, Barbados (13°15′N, 59°30′W), during April and October 1994, in support of Measurement of Air Pollution From Satellite (MAPS) Space Radar Laboratory (SRL) missions SRL‐1 and SRL‐2, respectively, measuring middle tropospheric CO from space. Observed median CO levels from the three surface sites during these two MAPS missions approximate the monthly median for 1994 and are mostly typical of data from prior years. For two of the sites, computed mission isentropic back‐trajectory ensemble probability fields are compared to seasonal (March‐May and September‐November) probability fields for 1994 and 1986–1995. Such comparisons help gauge the representativeness of (1) observed surface air quality at, and (2) isentropic flow to, these sites during the mission periods, in terms of intraseasonal and interannual variability. Results appear consistent with longer‐term flow climatological data and confirm the SRL‐1 and SRL‐2 mission periods are generally representative of the climatology applicable to these sites for the time of year. Lower free troposphere in situ CO data were acquired from an aircraft over the Maryland Eastern Shore on April 14 and October 3, 4, and 6. During the April flight a nearly linear gradient in CO with pressure from 1000–650 mbar of 225‐150 parts per billion by volume (ppbv) was observed. At 650 mbar, CO was quite steady around 150 ppbv; this value compares favorably with the MAPS CO data for the closest 5° ×; 5° grid box averaged April 13–15 of 105–120 ppbv. During SRL‐2 a three flight CO average of 125 ppbv observed at ∼725 mbar is in good agreement with the closest MAPS 5° × 5° grid box averaged October 3–7 of 90–105 ppbv. A layer of elevated CO at 845–740 mbar, most likely the result of synoptic‐scale transport, was observed during the October flights and seen to dissipate with time. The MAPS cloud‐filtered second‐by‐second CO data during concurrent shuttle overflights show temporal structure consistent with the in situ observations, indicating the MAPS weighting function may be capable of discerning features at lower altitudes than thought previously. DA - 1998/8/20/ PY - 1998/8/20/ DO - 10.1029/97JD01837 VL - 103 IS - D15 SP - 19305-19316 SN - 2169-8996 ER - TY - JOUR TI - Genetic mapping of QTLs affecting tree growth and architecture in Populus: implication for ideotype breeding AU - Wu, RL T2 - THEORETICAL AND APPLIED GENETICS DA - 1998/3// PY - 1998/3// DO - 10.1007/s001220050761 VL - 96 IS - 3-4 SP - 447-457 SN - 1432-2242 KW - growth KW - ideotype breeding KW - Populus KW - QTL mapping KW - quantitative variation ER - TY - JOUR TI - Estimating species richness: The importance of heterogeneity in species detectability AU - Boulinier, T AU - Nichols, JD AU - Sauer, , JR AU - Hines, JE AU - Pollock, KH T2 - ECOLOGY DA - 1998/4// PY - 1998/4// DO - 10.2307/176597 VL - 79 IS - 3 SP - 1018-1028 SN - 1939-9170 KW - capture-recapture KW - community ecology KW - detectability KW - heterogeneity KW - model selection KW - North American Breeding Bird Survey KW - species richness ER - TY - JOUR TI - Dispersion modeling and simulation in subsurface contaminant transport AU - Butera, JV AU - Fitzpatrick, BG AU - Wypasek, CJ T2 - MATHEMATICAL MODELS & METHODS IN APPLIED SCIENCES AB - In this paper, we examine three separate approaches to analyze the spatial dispersion of a subsurface contaminant. These methods are contrasted against traditional models to demonstrate their feasibility and usefulness. Lastly, numerical simulations illustrate the effectiveness of these approaches. DA - 1998/11// PY - 1998/11// DO - 10.1142/S0218202598000548 VL - 8 IS - 7 SP - 1183-1197 SN - 0218-2025 ER - TY - JOUR TI - Achieving uniformity in a semiconductor fabrication process using spatial modeling AU - Hughes-Oliver, JM AU - Lu, JC AU - Davis, JC AU - Gyurcsik, RS T2 - JOURNAL OF THE AMERICAN STATISTICAL ASSOCIATION AB - Abstract Material is deposited onto the wafer surface during several steps of wafer fabrication. This material must be deposited evenly across the entire wafer surface, close to the targeted thickness, and with little wafer-to-wafer variability. But unequal variances across the wafer and under different process conditions, as well as nonstationary correlation across a wafer, make these goals difficult to achieve, because traditional methods for optimizing deposition processes assume homogeneity and independence. We avoid these assumptions and determine the best settings of process variables using physically motivated statistical models for the mean response, unequal variances, and nonstationary spatial correlation structure. Data from a rapid thermal chemical vapor deposition process is used to illustrate the approach. A simulation exercise demonstrates the advantages of fitting flexible variance models and using appropriate performance measures. DA - 1998/3// PY - 1998/3// DO - 10.2307/2669600 VL - 93 IS - 441 SP - 36-45 SN - 0162-1459 KW - nonstationary correlation KW - optimality criteria KW - repeatability KW - restricted maximum likelihood KW - spatial correlation KW - variance modeling ER - TY - JOUR TI - Inheritance of resistance to southern corn rust in tropical by corn-belt maize populations AU - Holland, JB AU - Uhr, DV AU - Jeffers, D AU - Goodman, MM T2 - THEORETICAL AND APPLIED GENETICS DA - 1998/2// PY - 1998/2// DO - 10.1007/s001220050732 VL - 96 IS - 2 SP - 232-241 SN - 0040-5752 KW - Puccinia polysora KW - RFLP markers KW - partial resistance ER - TY - JOUR TI - Estimating aflatoxin in farmers' stock peanut lots by measuring aflatoxin in various peanut-grade components AU - Whitaker, T. B. AU - Hagler, W. M. AU - Giesbrecht, F. G. AU - Dorner, J W. AU - Dowell, F. E. AU - Cole, R. J. T2 - Journal of AOAC International DA - 1998/// PY - 1998/// VL - 81 IS - 1 SP - 61-67 ER - TY - JOUR TI - Developmental factors responsible for heterosis in aspen hybrids (Populus tremuloides x P-tremula) AU - Li, B. L. AU - Howe, G. T. AU - Wu, R. L. T2 - Tree Physiology AB - Juvenile growth and bud set phenology were analyzed to study the biological basis of heterosis (hybrid vigor) in interspecific hybrids of Populus tremuloides Michx. (T) and P. tremula L. (Ta). Growth, measured as seedling volume index, was significantly higher for each of the two reciprocal interspecific crosses, T x Ta and Ta x T, than for the T x T intraspecific cross. Broad-sense heritabilities were 2-6 times larger than narrow-sense heritabilities for growth and shoot components in the T x T intraspecific cross, suggesting an important role for dominance or overdominance in aspen growth. Previous genetic analyses have indicated that hybrid vigor may be the result of overdominance at several key loci each with an allele inherited from each of parental species. Internode length and leaf number contributed substantially to the heterosis of stem volume, but their effects on heterosis differed between the T x Ta and Ta x T hybrids. In T x Ta seedlings, heterosis of stem volume was attributed to a high diameter growth rate, whereas in Ta x T seedlings heterosis of stem volume was probably the result of delayed bud set resulting in a longer duration of height growth. In addition to internode number and length and leaf number, other morphological or physiological components might affect heterosis, for example, extended leaf retention. DA - 1998/// PY - 1998/// DO - 10.1093/treephys/18.1.29 VL - 18 IS - 1 SP - 29-36 ER - TY - JOUR TI - The class poster conference as a teaching tool AU - Hess, G. R. AU - Brooks, E. N. T2 - Journal of Natural Resources and Life Sciences Education DA - 1998/// PY - 1998/// VL - 27 IS - 1998 SP - 155-158 ER - TY - JOUR TI - Relative-error prediction AU - Park, H AU - Stefanski, LA T2 - STATISTICS & PROBABILITY LETTERS AB - We derive the form of the best mean squared relative error predictor of Y given X. Some methods of estimating predictors with good relative error properties are proposed and studied via simulation. The methods are illustrated with an example in which county-level gasoline sales are predicted from county-level population. DA - 1998/10/15/ PY - 1998/10/15/ DO - 10.1016/S0167-7152(98)00088-1 VL - 40 IS - 3 SP - 227-236 SN - 0167-7152 KW - prediction KW - power-of-the-mean model KW - relative error KW - relative least squares KW - variance function ER - TY - JOUR TI - On the existence of normal modes of damped discrete-continuous systems AU - Banks, HT AU - Luo, ZH AU - Bergman, LA AU - Inman, DJ T2 - JOURNAL OF APPLIED MECHANICS-TRANSACTIONS OF THE ASME AB - In this paper we investigate a class of combined discrete-continuous mechanical systems consisting of a continuous elastic structure and a finite number of concentrated masses, elastic supports, and linear oscillators of arbitrary dimension. After the motion equations for such combined systems are derived, they are formulated as an abstract evolution equation on an appropriately defined Hilbert space. Our main objective is to ascertain conditions under which the combined systems have classical normal modes. Using the sesquilinear form approach, we show that unless some matching conditions are satisfied, the combined systems cannot have normal modes even if Kelvin-Voigt damping is considered. DA - 1998/12// PY - 1998/12// DO - 10.1115/1.2791942 VL - 65 IS - 4 SP - 980-989 SN - 0021-8936 ER - TY - JOUR TI - MAPS - Preface AU - Reichle, HG AU - Connors, VS AU - Olson, J AU - Thompson, A T2 - JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES AB - Journal of Geophysical Research: AtmospheresVolume 103, Issue D15 p. 19283-19284 Free Access Preface [to special section on MAPS] Henry G. Reichle Jr., Henry G. Reichle Jr.Search for more papers by this authorVickie S. Connors, Vickie S. ConnorsSearch for more papers by this authorJennifer Olson, Jennifer OlsonSearch for more papers by this authorAnne Thompson Olson, Anne Thompson OlsonSearch for more papers by this author Henry G. Reichle Jr., Henry G. Reichle Jr.Search for more papers by this authorVickie S. Connors, Vickie S. ConnorsSearch for more papers by this authorJennifer Olson, Jennifer OlsonSearch for more papers by this authorAnne Thompson Olson, Anne Thompson OlsonSearch for more papers by this author First published: 01 August 1998 https://doi.org/10.1029/98JD01108Citations: 2AboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL No abstract is available for this article. References Brasseur, G., S. Solomon, Aeronomy of the Middle Atmosphere 2nd ed., 452, D. Reidel, Norwell, Mass., 1986. Christopher, S. A., D. V. Kliche, R. M. Welch, andV. S. Connors, Satellite investigations of fire, smoke, and carbon monoxide during the April 1994 MAPS mission: Case studies over tropical Asia,J. Geophys. Res., 103(D15), 1998. Connors, V. S., P. C. Novelli, H. G. Reichle Jr., Space shuttle views changing carbon monoxide in lower atmosphere, Eos Trans. AGU, 77, 466, 1996. Crutzen, P. J., L. E. Heidt, J. P. Krasnec, W. H. Pollack, W. Seiler, Biomass burning as a source of atmospheric gases CO, H2, H2O, NO, CH3Cl, and COS, Nature, 282, 253, 1979. Doddridge, B. G., R. M. Morales, K. P. Rhoads, J. T. Merrill, P. C. Novelli, R. R. Dickerson, V. S. Connors, andH. G. Reichle Jr., Ground-based and airborne observations of carbon monoxide during NASA/MAPS missions SRL-1 and SRL-2.,J. Geophys. Res., 103(D15), 1998. Levy II, H., Normal atmosphere: Large radical and formaldehyde concentrations predicted, Science, 173, 141, 1971. Logan, J. A., J. Prather, S. C. Wofsy, M. B. McElroy, Tropospheric chemistry: A global perspective, J. Geophys. Res., 86, 7210, 1981. Mak, J. E., andC. A. M. Brenninkmeijer, Measurement of 13CO and C18O in the free troposphere,J. Geophys. Res., 103(D15), 1998. McConnell, J. C., M. B. McElroy, S. C. Wofsy, Natural sources of atmospheric CO, Nature, 233, 187, 1971. Novelli, P. C., et al.,An internally consistent set of globally distributed atmospheric carbon monoxide mixing ratios developed using results from an intercomparison of measurements,J. Geophys. Res., 103(D15), 1998. Pougatchev, N. S., et al.,Ground-based infrared solar spectroscopic measurements of carbon monoxide during 1994 MAPS flights,J. Geophys. Res., 103(D15), 1998. Reichle Jr., H. G., V. S. Connors, J. A. Holland, W. D. Hypes, H. A. Wallio, J. C. Casas, B. B. Gormsen, M. S. Saylor, W. D. Hesketh, Middle and upper tropospheric carbon monoxide mixing rations as measured by a satellite-borne remote sensor during November 1981, J. Geophys. Res., 91, 10865– 10887, 1986. Reichle Jr., H. G., V. S. Connors, J. A. Holland, R. T. Sherrill, H. A. Wallio, J. C. Casas, E. P. Condon, B. B. Gormsen, W. Seiler, The distribution of middle tropospheric carbon monoxide during early October 1984, J. Geophys. Res., 95, 9845– 9856, 1990. Robinson, E., R. C. Robbins, Sources, abundance and fate of gaseous atmospheric pollutants, supplemental reportRes. Proj. PR-6755Stanford Res. Inst., Menlo Park, Calif., 1969. Scheel, H. E., E.-G. Brunke, R. Sladkovic, andW. Seiler, In situ CO concentrations at the sites Zugspitze (47°N, 11°E) and Cape Point (34°S, 18°E) in April and October 1994,J. Geophys. Res., 103(D15), 1998. Sze, N. D., Anthropogenic CO emissions: Implications for the atmospheric CO-OH-CH4 cycle, Science, 195, 673– 674, 1977. Weinstock, B., Carbon monoxide: Residence time in the atmosphere, Science, 166, 224, 1969. Wofsy, S. C., J. C. McConnell, M. B. McElroy, Atmospheric CH4, CO, and CO2, J. Geophys. Res., 77, 4477, 1972. Yurganov, L. N., D. A. Jaffe, E. Pullman, andP. C. Novelli, Total column and surface densities of atmospheric carbon monoxide in Alaska, 1995,J. Geophys. Res., 103(D15), 1998. Zimmerman, P. R., R. B. Chatfield, J. Fishman, P. J. Crutzen, P. L. Hanst, Estimates on the production of CO and H2 from the oxidation of hydrocarbon emissions from vegetation, Geophys. Res. Lett., 5, 679, 1978. Citing Literature Volume103, IssueD1520 August 1998Pages 19283-19284 This article also appears in:MAPS ReferencesRelatedInformation DA - 1998/8/20/ PY - 1998/8/20/ DO - 10.1029/98JD01108 VL - 103 IS - D15 SP - 19283-19284 SN - 2169-8996 ER - TY - JOUR TI - Detection of non-symmetrical damage in smart plate-like structures AU - Banks, HT AU - Emeric, PR T2 - JOURNAL OF INTELLIGENT MATERIAL SYSTEMS AND STRUCTURES AB - A two-dimensional model for in-plane vibrations of a cantilever plate with a nonsymmetrical damage is used in the context of defect identification in materials with piezoelectric ceramic patches bonded to their surface. These patches can act both as actuators and sensors in a selfanalyzing fashion, which is a characteristic of smart materials. A Galerkin method is used to approximate the dynamic response of these structures. The natural frequency shifts due to the damage are estimated numerically and compared to experimental data obtained from tests on cantilever aluminum plate-like structures damaged at different locations with defects of different depths. The damage location and extent are determined by an enhanced least square identification method. Efficacy of the frequency shift based algorithms is demonstrated using experimental data. DA - 1998/10// PY - 1998/10// DO - 10.1177/1045389x9800901005 VL - 9 IS - 10 SP - 818-828 SN - 1045-389X ER - TY - JOUR TI - Complex interactions of fish, snails, and littoral zone periphyton AU - McCollum, E. W. AU - Crowder, L. B. AU - McCollum, S. A. T2 - Ecology (Brooklyn, New York, N.Y.) DA - 1998/// PY - 1998/// VL - 79 IS - 6 SP - 1980-1984 ER - TY - JOUR TI - Analyzing real estate data problems using the Gibbs sampler AU - Knight, , JR AU - Sirmans, CF AU - Gelfand, AE AU - Ghosh, SK T2 - REAL ESTATE ECONOMICS AB - Real estate data are often characterized by data irregularities: missing data, censoring or truncation, measurement error, etc. Practitioners often discard missing‐ or censored‐data cases and ignore measurement error. We argue here that an attractive remedy for these irregularity problems is simulation‐based model fitting using the Gibbs sampler. The style of the paper is primarily pedagogic, employing a simple illustration to convey the essential ideas, unobscured by implementation complications. Focusing on the missing‐data problem, we show dramatic improvement in inference by retaining rather than deleting cases of partially observed data. We also detail Gibbs‐sampler usage for other data problems. DA - 1998/// PY - 1998/// DO - 10.1111/1540-6229.00753 VL - 26 IS - 3 SP - 469-492 SN - 1080-8620 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-0032221482&partnerID=MN8TOARS ER - TY - JOUR TI - A numerical modeling study of mesoscale cyclogenesis to the east of the Korean peninsula AU - Lee, TY AU - Park, YY AU - Lin, YL T2 - MONTHLY WEATHER REVIEW AB - Numerical simulations and the analysis of observational data are employed to understand the mesoscale cyclogenesis in a polar airstream that occurred over the sea to the east of the Korean peninsula on 28–29 January 1995. The observational analysis shows that a mesoscale low develops over the southeastern East Sea (Japan Sea) on 29 January 1995. Satellite imagery also indicates that a meso-β-scale vortex forms on the lee side of the northern Korean mountain complex (KMC), which is located in the northern Korean peninsula, and that a meso-α-scale cyclone develops over the southeastern East Sea at a later time. The mesoscale cyclone forms in the lower troposphere with strong baroclinicity and cyclonic circulation under the influence of an upper-level synoptic-scale cold vortex. Numerical simulation has captured major features of the observed cyclogenesis very well. The cyclogenesis occurs in a progressive manner. Basically, four distinctive stages of the cyclogenesis are identified. 1) First, a surface pressure trough forms on the lee side of the KMC under a northwesterly synoptic-scale flow that is deflected anticyclonically over the KMC. 2) Second, the lee trough deepens further into a strong convergence zone and a meso-β-scale vortex. 3) Next, the meso-β-scale vortex develops into a meso-α-scale vortex as the vortex and the trough begin to move southeastward from the lee of the KMC. 4) Finally, the surface trough deepens into a closed low and the meso-α-scale vortex becomes collocated with this deepening surface low to form a meso-α-scale cyclone over the southeastern East Sea. Several sensitivity experiments are performed to isolate the effects of a topography, warmer sea surface, diurnal thermal forcing, and latent heat release. During stages 1 and 2, it is found that the KMC and low-level baroclinicity are responsible for generating the strong lee trough and vortex. During stage 3, the development of the meso-α-scale vortex is brought on by the tilting of horizontal vorticity and vertical stretching in a synoptic-scale cyclonic circulation. In the final stage, the condensational heating plays the key role for the development of the meso-α-scale cyclone under the influence of an upper-level synoptic-scale cold vortex. The presence of the warm sea surface is found to be a necessary condition for the development of a polar air convergence zone and the mesoscale cyclone. It is also found that the low-level baroclinicity is essential for the present case of mesoscale cyclogenesis. DA - 1998/9// PY - 1998/9// DO - 10.1175/1520-0493(1998)126<2305:ANMSOM>2.0.CO;2 VL - 126 IS - 9 SP - 2305-2329 SN - 0027-0644 ER - TY - JOUR TI - Utilization of coupling effects in compensator design for structural acoustic systems AU - Banks, HT AU - Demetriou, MA AU - Smith, RC T2 - JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA AB - The quantification and utilization of coupling effects in a prototypical structural acoustic system are examined in this paper. In typical systems, the coupling mechanisms are manifested in two ways. The first leads to the transfer of energy from an ambient field to an adjacent structure and is often responsible for exogenous structural excitation. The second involves the transfer of energy from the vibrating structure to an adjacent field. This is the source of structure-borne noise and is ultimately the mechanism through which structural actuators are utilized to attenuate noise. The examples presented here demonstrate that in fully coupled systems, both mechanisms should be incorporated to accurately model system dynamics. The examples also illustrate advantages and limitations of compensators which utilize the accurate modeling of the structural coupling. DA - 1998/2// PY - 1998/2// DO - 10.1121/1.421205 VL - 103 IS - 2 SP - 872-887 SN - 0001-4966 ER - TY - JOUR TI - Stochastic integration rules for infinite regions AU - Genz, A AU - Monahan, J T2 - SIAM JOURNAL ON SCIENTIFIC COMPUTING AB - Stochastic integration rules are derived for infinite integration intervals, generalizing rules developed by Siegel and O'Brien [ SIAM J. Sci. Statist. Comput., 6 (1985), pp. 169--181] for finite intervals. Then random orthogonal transformations of rules for integrals over the surface of the unit m-sphere are used to produce stochastic rules for these integrals. The two types of rules are combined to produce stochastic rules for multidimensional integrals over infinite regions with Normal or Student-t weights. Example results are presented to illustrate the effectiveness of the new rules. DA - 1998/3// PY - 1998/3// DO - 10.1137/S1064827595286803 VL - 19 IS - 2 SP - 426-439 SN - 1064-8275 KW - Monte Carlo KW - multiple integrals KW - numerical integration KW - statistical computation ER - TY - JOUR TI - Statistical tests of neutrality in the age of weak selection AU - Wayne, ML AU - Simonsen, KL T2 - TRENDS IN ECOLOGY & EVOLUTION AB - Why review statistical tests of neutrality at a time when pan-selectionists and pan-neutralists alike seem to have been replaced by weak selectionists? First, we still don't actually know how variation is maintained at the molecular level; and second, tests of neutrality have a utility for evolutionary biologists beyond the neutralist/selectionist debate. New tests and variations on the existing tests are arising practically every month. From the complementary viewpoints of an empiricist and a theoretician, we sample the recent literature on tests of statistical neutrality and discuss the motivations, applications, assumptions, interpretations and future directions of these tests. DA - 1998/6// PY - 1998/6// DO - 10.1016/S0169-5347(98)01360-3 VL - 13 IS - 6 SP - 236-240 SN - 1872-8383 ER - TY - JOUR TI - Speed of invasion in lattice population models: pair-edge approximation AU - Ellner, SP AU - Sasaki, A AU - Haraguchi, Y AU - Matsuda, H T2 - JOURNAL OF MATHEMATICAL BIOLOGY DA - 1998/4// PY - 1998/4// DO - 10.1007/s002850050109 VL - 36 IS - 5 SP - 469-484 SN - 0303-6812 KW - invasion KW - lattice model KW - pair approximation KW - wave speed KW - stochastic spatial model ER - TY - JOUR TI - Setting bounds for the likelihood ratio when multiple hypotheses are postulated AU - Buckleton, J. S. AU - Evett, I. W. AU - Weir, B. S. T2 - Science and Justice DA - 1998/// PY - 1998/// VL - 38 IS - 1 SP - 23-26 ER - TY - JOUR TI - Nonlinear genotypic response to macro- and microenvironments AU - Wu, RL AU - DM O'Malley, T2 - THEORETICAL AND APPLIED GENETICS DA - 1998/4// PY - 1998/4// DO - 10.1007/s001220050787 VL - 96 IS - 5 SP - 669-675 SN - 1432-2242 KW - additive-multiplicative model KW - ANOVA KW - macroenvironment KW - microenvironment KW - genotype x environment interaction ER - TY - JOUR TI - Assessment of the condition of agricultural lands in five mid-Atlantic states AU - Hellkamp, AS AU - Shafer, , SR AU - Campbell, CL AU - Bay, JM AU - Fiscus, DA AU - Hess, GR AU - McQuaid, BF AU - Munster, MJ AU - Olson, GL AU - Peck, SL AU - Easterling, KN AU - Sidik, K AU - Tooley, MB T2 - ENVIRONMENTAL MONITORING AND ASSESSMENT DA - 1998/6// PY - 1998/6// DO - 10.1023/A:1005955807061 VL - 51 IS - 1-2 SP - 317-324 SN - 0167-6369 ER - TY - JOUR TI - An algorithm for the construction of spatial coverage designs with implementation in SPLUS AU - Royle, JA AU - Nychka, D T2 - COMPUTERS & GEOSCIENCES AB - Space-filling “coverage” designs are spatial sampling plans which optimize a distance-based criterion. Because they do not depend on the covariance structure of the process to be sampled, coverage designs are computed more efficiently than designs that are optimal for mean-squared-error criteria. This paper presents an efficient algorithm for the construction of coverage designs and evaluates its performance in terms of computation time and effectiveness at finding “good” designs. Results suggest that near-optimal designs for reasonably large problems can be computed efficiently. The algorithm is implemented in the statistical programming language SPLUS and examples of the construction of coverage designs are given involving an existing network of ozone monitoring sites. DA - 1998/6// PY - 1998/6// DO - 10.1016/s0098-3004(98)00020-x VL - 24 IS - 5 SP - 479-488 SN - 0098-3004 KW - spatial design KW - space-filling designs KW - spatial statistics KW - spatial sampling KW - network design ER -