William James Showers

Works (36)

Updated: April 3rd, 2024 23:01

2019 journal article

Hysteresis analysis of nitrate dynamics in the Neuse River, NC

SCIENCE OF THE TOTAL ENVIRONMENT, 652, 889–899.

By: E. Baker n & W. Showers n

author keywords: Nitrate; Hysteresis; Nutrient dynamics; Storm runoff; Eutrophication
TL;DR: A high-resolution nitrate monitoring record over a 10-year period in the Neuse River Basin near Clayton, North Carolina shows that dry soil conditions and frequent small storms during summer leads to greater nitrate transport on the rising limb, in contrast to slower, groundwater-driven inputs during the rest of the year. (via Semantic Scholar)
Source: Web Of Science
Added: January 14, 2019

2015 journal article

Key metabolites in tissue extracts ofElliptio complanataidentified using1H nuclear magnetic resonance spectroscopy

Conservation Physiology, 3(1), cov023.

By: J. Hurley-Sanders n, J. Levine n , S. Nelson n , J. Law n, W. Showers n & M. Stoskopf n

author keywords: Freshwater mussels; metabolites; nuclear magnetic resonance spectroscopy
TL;DR: Preliminary studies provide evidence for potential use of digestive gland and mantle tissue for studying physiological impacts of location, sex and reproductive condition on Elliptio complanata. (via Semantic Scholar)
UN Sustainable Development Goal Categories
14. Life Below Water (Web of Science; OpenAlex)
15. Life on Land (Web of Science)
Sources: Web Of Science, NC State University Libraries, Crossref
Added: August 6, 2018

2015 journal article

Tissue extraction methods for metabolic profiling of a freshwater bivalve, Elliptio complanata

American Malacological Bulletin, 33(2), 185–194.

By: J. Hurley-Sanders n, M. Stoskopf n, S. Nelson, W. Showers n, J. Law n, H. Gracz*, J. Levine n 

author keywords: freshwater bivalve; metabolomics; NMR; nuclear magnetic resonance; Ringer's solution
TL;DR: Ringer's solution is simple to use, safe and consistent and bears consideration when selecting an extraction protocol for 1H nuclear magnetic resonance experiments, particularly in the 3–4.5 ppm sugar/amino acid range. (via Semantic Scholar)
UN Sustainable Development Goal Categories
Sources: Web Of Science, NC State University Libraries, Crossref
Added: August 6, 2018

2011 journal article

Spatial variability of the stable isotope (δ15N) composition in two freshwater bivalves (Corbicula fluminea and Elliptio complanata)

Journal of Freshwater Ecology, 26(1), 19–24.

By: J. Bucci n, J. Levine n  & W. Showers n

author keywords: stable nitrogen isotopes; freshwater bivalves; biomonitors
UN Sustainable Development Goal Categories
14. Life Below Water (Web of Science)
Sources: Web Of Science, NC State University Libraries, Crossref
Added: August 6, 2018

2009 journal article

Deep-sea benthic diversity linked to seasonality of pelagic productivity

DEEP-SEA RESEARCH PART I-OCEANOGRAPHIC RESEARCH PAPERS, 56(5), 835–841.

By: B. Corliss*, C. Brown *, X. Sun* & W. Showers n

author keywords: Deep-sea diversity; Benthos; Foraminifera; Seasonality
UN Sustainable Development Goal Categories
14. Life Below Water (Web of Science; OpenAlex)
15. Life on Land (Web of Science)
Source: Web Of Science
Added: August 6, 2018

2009 journal article

Stable oxygen and carbon isotope profiles in an invasive bivalve (Corbicula fluminea) in North Carolina watersheds

Geochimica Et Cosmochimica Acta, 73(11), 3234–3247.

By: J. Bucci n, W. Showers n, B. Genna n & J. Levine n 

UN Sustainable Development Goal Categories
14. Life Below Water (Web of Science)
15. Life on Land (Web of Science)
Sources: Web Of Science, Crossref, NC State University Libraries
Added: August 6, 2018

2008 journal article

Back-trajectory analysis and source-receptor relationships: Particulate matter and nitrogen isotopic composition in rainwater

JOURNAL OF THE AIR & WASTE MANAGEMENT ASSOCIATION, 58(9), 1215–1222.

By: C. Occhipinti n, V. Aneja n , W. Showers n & D. Niyogi n

Contributors: C. Occhipinti n, V. Aneja n , W. Showers n & D. Niyogi n

MeSH headings : Analysis of Variance; Atmosphere; Isotopes / analysis; Nitrogen / analysis; Particulate Matter / analysis; Rain / chemistry; United States
TL;DR: Findings indicate that transporting air over this region can affect nitrogen concentrations in precipitation at sites as far as 50 mi away, and the importance of pollution sources, including animal agricultural activity, and meteorology on rainfall chemistry as well as the implications in fine particulate matter formation is examined. (via Semantic Scholar)
UN Sustainable Development Goal Categories
Sources: Web Of Science, ORCID, NC State University Libraries
Added: August 6, 2018

2008 journal article

Nitrate contamination in groundwater on an urbanized dairy farm

ENVIRONMENTAL SCIENCE & TECHNOLOGY, 42(13), 4683–4688.

By: W. Showers n, B. Genna n, T. McDade n, R. Bolich n & J. Fountain n

MeSH headings : Bromides / analysis; Chlorides / analysis; Dairying; Environmental Monitoring / statistics & numerical data; Flow Injection Analysis; Magnetics; Nitrates / analysis; Nitrogen Isotopes / analysis; North Carolina; Urban Renewal; Water Pollutants, Chemical / analysis; Water Supply / analysis
TL;DR: The isotope and Cl/Br ratios indicate that nitrate contamination in these drinking wells are not from septic systems, but are the result of animal waste leached from pastures into groundwater during 35 years of dairy operations which did not violate any existing regulations. (via Semantic Scholar)
UN Sustainable Development Goal Categories
11. Sustainable Cities and Communities (OpenAlex)
Source: Web Of Science
Added: August 6, 2018

2008 journal article

Uncertainties in the oxygen isotopic composition of barium sulfate induced by coprecipitation of nitrate

RAPID COMMUNICATIONS IN MASS SPECTROMETRY, 22(19), 2971–2976.

By: G. Michalski *, M. Kasem*, J. Rech *, S. Adieu*, W. Showers n, B. Genna n, M. Thiemens *

MeSH headings : Artifacts; Barium Sulfate / chemistry; Fractional Precipitation; Mass Spectrometry / methods; Nitrates / chemistry; Oxygen Isotopes / analysis; Reproducibility of Results; Sensitivity and Specificity
TL;DR: The fraction of coprecipitated nitrate appears to increase with decreasing pH and is also affected by the nature of the cations in the precipitating solution and the size of the oxygen isotope artifact in sulfate depends both on the amount ofCoprecipitate nitrate and the delta(18)O and Delta(17)O values of the nitrate, both of which can be highly variable. (via Semantic Scholar)
UN Sustainable Development Goal Categories
6. Clean Water and Sanitation (OpenAlex)
13. Climate Action (Web of Science)
Source: Web Of Science
Added: August 6, 2018

2008 journal article

Valve Gape Response to Turbidity in Two Freshwater Bivalves (Corbicula flumineaandLampsilis radiata)

Journal of Freshwater Ecology, 23(3), 479–483.

By: J. Bucci*, W. Showers*, J. Levine*  & B. Usry n

TL;DR: A significant difference was found in valve gape response to the turbidity between Corbicula fluminea and Lampsilis radiata with simulated storm event. (via Semantic Scholar)
UN Sustainable Development Goal Categories
14. Life Below Water (Web of Science; OpenAlex)
15. Life on Land (Web of Science)
Sources: Web Of Science, Crossref, NC State University Libraries
Added: August 6, 2018

2007 journal article

A comparison of blue crab and bivalve delta N-15 tissue enrichment in two North Carolina estuaries

Environmental Pollution, 145(1), 299–308.

By: J. Bucci n, S. Rebach n, D. Demaster n & W. Showers n

MeSH headings : Animals; Bivalvia / metabolism; Body Size; Brachyura / metabolism; Corbicula / metabolism; Environmental Monitoring / methods; Fishes / metabolism; Linear Models; Male; Nitrogen Isotopes / analysis; North Carolina; Rivers; Tissue Distribution; Water Pollutants, Chemical / analysis
TL;DR: It is suggested that a relationship may exist between nutrient sources and subsequent energy transfer to estuarine consumers in two North Carolina estuaries and an inverse relationship exists between invertebrate tissue enrichment and indicators of water quality across estuarist sites. (via Semantic Scholar)
UN Sustainable Development Goal Categories
14. Life Below Water (Web of Science)
Source: NC State University Libraries
Added: August 6, 2018

2007 review

Chemical sensor networks for the aquatic environment

[Review of ]. CHEMICAL REVIEWS, 107(2), 623–640.

By: K. Johnson  n, J. Needoba n, S. Riser  n & W. Showers n

TL;DR: Monterey Bay Aquarium Research Institute, 7700 Sandholdt Road, Moss Landing, California 95039, School of Oceanography, University ofWashington, Seattle, Washington 98195-7940, Department of Marine, Earth and Atmospheric Sciences, North Carolina State University,Raleigh, North North Carolina 27695. (via Semantic Scholar)
UN Sustainable Development Goal Categories
13. Climate Action (Web of Science)
14. Life Below Water (Web of Science; OpenAlex)
Source: Web Of Science
Added: August 6, 2018

2007 journal article

Stable isotope analyses (delta N-15 and delta C-13) of the trophic relationships of Callinectes sapidus in two north Carolina estuaries

ESTUARIES AND COASTS, 30(6), 1049–1059.

By: J. Bucci n, W. Showers n, S. Rebach n, D. DeMaster n & B. Genna n

TL;DR: It is found that blue crab δ13C values increased with salinity from upper to lower regions along both estuaries, and consumers sampled from the upper NRE may be influenced by higher nitrogen input from urban land use and municipal wastewater. (via Semantic Scholar)
UN Sustainable Development Goal Categories
6. Clean Water and Sanitation (OpenAlex)
14. Life Below Water (Web of Science)
Source: Web Of Science
Added: August 6, 2018

2007 journal article

Temporal and spatial variability in stable isotope compositions of a freshwater mussel: implications for biomonitoring and ecological studies

OECOLOGIA, 152(1), 140–150.

By: L. Gustafson  n, W. Showers n, T. Kwak n , J. Levine n  & M. Stoskopf n

author keywords: Elliptio complanata; delta N-15; delta C-13; nutrient loading; tissue turnover; isotopic baseline
MeSH headings : Animals; Carbon Isotopes; Ecology; Environmental Monitoring; Food Chain; Geography; Hemolymph / chemistry; Nitrogen Isotopes; North Carolina; Rivers / chemistry; Unionidae / chemistry; Unionidae / metabolism
TL;DR: It is concluded that bivalves serve best as biomonitors of chronic, rather than acute, fluctuations in stream nutrient loads, and initial evidence of their suitability as time-integrated isotopic baselines for community studies is provided. (via Semantic Scholar)
UN Sustainable Development Goal Categories
14. Life Below Water (Web of Science)
Sources: Web Of Science, NC State University Libraries
Added: August 6, 2018

2006 journal article

Impact of large poultry operations on groundwater: Stable 15N isotopes of nitrate assessment

International Journal of Poultry Science, 5(4), 318.

By: W. Showers*, C. Williams* & G. Jennings*

Source: NC State University Libraries
Added: August 6, 2018

2006 journal article

Influence of seasonal primary productivity on delta C-13 of North Atlantic deep-sea benthic foraminifera

DEEP-SEA RESEARCH PART I-OCEANOGRAPHIC RESEARCH PAPERS, 53(4), 740–746.

By: B. Corliss*, X. Sun*, C. Brown * & W. Showers n

author keywords: benthic; foraminifera; deep-sea; paleoceanography; North Atlantic
UN Sustainable Development Goal Categories
13. Climate Action (Web of Science)
14. Life Below Water (Web of Science)
Source: Web Of Science
Added: August 6, 2018

2006 review

The effect of primary productivity and seasonality on the distribution of deep-sea benthic foraminifera in the North Atlantic

[Review of ]. DEEP-SEA RESEARCH PART I-OCEANOGRAPHIC RESEARCH PAPERS, 53(1), 28–47.

By: X. Sun*, B. Corliss*, C. Brown * & W. Showers n

author keywords: deep-sea benthic foraminifera; primary productivity; seasonality; North Atlantic
TL;DR: Deep-sea benthic foraminifera from 43 Holocene core tops in the North Atlantic were studied to evaluate the influence of primary productivity and the seasonality ofPrimary productivity on the distributional patterns of species, faunal assemblages, and microhabitat groups. (via Semantic Scholar)
UN Sustainable Development Goal Categories
13. Climate Action (Web of Science)
14. Life Below Water (Web of Science)
Source: Web Of Science
Added: August 6, 2018

2005 journal article

Evaluation of a nonlethal technique for hemolymph collection in Elliptio complanata, a freshwater bivalve (Mollusca: Unionidae)

Diseases of Aquatic Organisms, 65(2), 159–165.

By: L. Gustafson  n, M. Stoskopf*, A. Bogan*, W. Showers*, T. Kwak* , S. Hanlon, J. Levine n 

author keywords: unionidae; freshwater mussels; hemolymph; nonlethal sampling
MeSH headings : Animals; Bivalvia; Blood Specimen Collection / methods; Evaluation Studies as Topic; Fresh Water; Hemolymph / chemistry; North Carolina; Survival Analysis
TL;DR: It is concluded that collection of hemolymph from the adductor sinus is safe for sampled E. complanata and should be explored as a relatively non-invasive, and potentially useful, approach to the evaluation of freshwater mussel health. (via Semantic Scholar)
UN Sustainable Development Goal Categories
14. Life Below Water (Web of Science; OpenAlex)
15. Life on Land (Web of Science)
Sources: Web Of Science, NC State University Libraries, Crossref
Added: August 6, 2018

2005 journal article

Nitrate movement in shallow ground water from swine-lagoon-effluent spray fields managed under current application regulations

JOURNAL OF ENVIRONMENTAL QUALITY, 34(5), 1828–1842.

By: D. Israel n, W. Showers n, M. Fountain n & J. Fountain n

MeSH headings : Animals; Environmental Monitoring / legislation & jurisprudence; Environmental Monitoring / statistics & numerical data; Fresh Water / chemistry; Manure / analysis; Nitrates / analysis; Nitrogen Isotopes / analysis; North Carolina; Oxygen Isotopes / analysis; Sus scrofa; Water Movements; Water Pollutants, Chemical / analysis
TL;DR: Measurement of delta18O and delta15N enrichment of nitrate in ground water throughout the WAF-riparian system indicated that denitrification has not caused significant 15N enrichment and delivery of some waste-derived nitrate N to the stream in shallow ground water. (via Semantic Scholar)
UN Sustainable Development Goal Categories
6. Clean Water and Sanitation (OpenAlex)
Source: Web Of Science
Added: August 6, 2018

2005 journal article

Reference ranges for hemolymph chemistries from Elliptio complanata of North Carolina

DISEASES OF AQUATIC ORGANISMS, 65(2), 167–176.

By: L. Gustafson*, M. Stoskopf*, W. Showers*, G. Cope, C. Eads*, R. Linnehan, T. Kwak* , B. Andersen*, J. Levine* 

author keywords: Elliptio complanata; hemolymph; hematology; reference ranges
MeSH headings : Animals; Bivalvia / chemistry; Bivalvia / parasitology; Blood Chemical Analysis; Body Weights and Measures; Fresh Water; Geography; Hemolymph / chemistry; Likelihood Functions; North Carolina; Reference Values; Statistics, Nonparametric
TL;DR: A set of reference ranges for clinical evaluation of hemolymph from a freshwater mussel species common to southeastern USA is developed to aid the interpretation of health measures from populations of E. complanata of similar geographic and seasonal origin. (via Semantic Scholar)
UN Sustainable Development Goal Categories
14. Life Below Water (Web of Science; OpenAlex)
15. Life on Land (Web of Science)
Sources: Web Of Science, NC State University Libraries
Added: August 6, 2018

2003 journal article

Low-level nitrate export from confined dairy farming detected in North Carolina streams using delta N-15

AGRICULTURE ECOSYSTEMS & ENVIRONMENT, 95(1), 103–110.

By: J. Karr*, W. Showers n & G. Jennings n

author keywords: nitrate; delta N-15; water quality; animal waste; dairy farming
Source: Web Of Science
Added: August 6, 2018

2002 article

Application of classification-tree methods to identify nitrate sources in ground water

JOURNAL OF ENVIRONMENTAL QUALITY, Vol. 31, pp. 1538–1549.

By: T. Spruill*, W. Showers n & S. Howe*

MeSH headings : Animals; Environmental Monitoring; Fertilizers; Manure; Models, Theoretical; Nitrates / analysis; Nitrates / classification; Poultry; Soil Pollutants / analysis; Swine; Water Pollutants / analysis; Water Supply
UN Sustainable Development Goal Categories
6. Clean Water and Sanitation (Web of Science; OpenAlex)
Source: Web Of Science
Added: August 6, 2018

2002 journal article

Escalation and extinction selectivity: morphology versus isotopic reconstruction of bivalve metabolism.

Evolution, 56(2), 284–291.

By: G. Dietl*, P. Kelley, R. Barrick n & W. Showers n

MeSH headings : Animals; Biological Evolution; Fossils; Geologic Sediments; Maryland; Mollusca / anatomy & histology; Mollusca / classification; Mollusca / growth & development; Mollusca / metabolism; Oxygen Consumption; Species Specificity
TL;DR: It is predicted that some morphologically non‐escalated species in previous tests of extinction selectivity should be reclassified as escalated because of their fast shell growth rates, which are positively correlated with metabolic rate and thus are potential indicators of level of escalation. (via Semantic Scholar)
Source: NC State University Libraries
Added: August 6, 2018

2002 journal article

Isotopic analysis of dinosaur bones

ANALYTICAL CHEMISTRY, 74(5), 142A–150A.

By: W. Showers n, R. Barrick* & B. Genna*

MeSH headings : Animals; Body Temperature Regulation / physiology; Bone and Bones / chemistry; Dinosaurs / physiology; Oxygen Isotopes / analysis; Phosphates / analysis
UN Sustainable Development Goal Categories
14. Life Below Water (Web of Science)
Source: Web Of Science
Added: August 6, 2018

2002 journal article

Nitrate source identification using delta N-15 in a ground water plume near an intensive swine operation

GROUND WATER MONITORING AND REMEDIATION, 22(2), 68–75.

By: J. Karr, W. Showers* & T. Hinson

Source: Web Of Science
Added: August 6, 2018

2002 personal communication

Reply to comments on 'Isotopic analysis of dinosaur bones'

By: W. Showers* & B. Genna*

Source: NC State University Libraries
Added: August 6, 2018

2002 journal article

Stable oxygen and hydrogen isotopic tracers in Amazon shelf waters during Amasseds

OCEANOLOGICA ACTA, 25(2), 71–78.

By: J. Karr n & W. Showers n

author keywords: Amazon; isotope; O-18; deuterium; hydrography
UN Sustainable Development Goal Categories
14. Life Below Water (OpenAlex)
Source: Web Of Science
Added: August 6, 2018

2001 journal article

Oxygen isotope variability in bones of wild caught and constant temperature reared sub-adult American alligators

JOURNAL OF THERMAL BIOLOGY, 26(3), 183–191.

By: M. Stoskopf n, R. Barrick n & W. Showers n

author keywords: bone; heterothermy; oxygen isotopes; alligator; reptile; thermoregulation
TL;DR: The thoracic vertebra had the highest mean delta18O(BP) ( per thousandSMOW), indicative of lower temperatures, and the lowest variability of bones in both groups of alligators, whereas the tibia was one of the warmest and more variable bones inboth groups ofalligators. (via Semantic Scholar)
UN Sustainable Development Goal Categories
14. Life Below Water (Web of Science; OpenAlex)
Source: Web Of Science
Added: August 6, 2018

2001 journal article

Persistent solar influence on north Atlantic climate during the Holocene

SCIENCE, 294(5549), 2130–2136.

By: G. Bond*, B. Kromer *, J. Beer*, R. Muscheler *, M. Evans *, W. Showers n, S. Hoffmann*, R. Lotti-Bond*, I. Hajdas*, G. Bonani

TL;DR: A solar forcing mechanism therefore may underlie at least the Holocene segment of the North Atlantic's “1500-year” cycle, potentially providing an additional mechanism for amplifying the solar signals and transmitting them globally. (via Semantic Scholar)
UN Sustainable Development Goal Categories
13. Climate Action (Web of Science)
14. Life Below Water (OpenAlex)
Source: Web Of Science
Added: August 6, 2018

2001 journal article

Tracing nitrate transport and environmental impact from intensive swine farming using delta nitrogen-15

JOURNAL OF ENVIRONMENTAL QUALITY, 30(4), 1163–1175.

By: J. Karr*, W. Showers n, J. Gilliam n & A. Andres*

MeSH headings : Agriculture; Ammonia / analysis; Animals; Ecosystem; Nitrates / analysis; Nitrogen Isotopes / analysis; Soil Pollutants / analysis; Swine; Waste Disposal, Fluid; Water Movements; Water Pollutants / analysis
TL;DR: This study shows that riparian buffers are not always adequate to prevent discharge of concentrated nitrate in ground water from commercial swine farms in the Mid-Atlantic Coastal Plain, and that additional measures are required to ensure non-discharge conditions. (via Semantic Scholar)
Source: Web Of Science
Added: August 6, 2018

1999 journal article

Oxygen isotopes from turtle bone: Applications for terrestrial paleoclimates?

PALAIOS, 14(2), 186–191.

By: R. Barrick*, A. Fischer & W. Showers*

UN Sustainable Development Goal Categories
14. Life Below Water (Web of Science; OpenAlex)
Source: Web Of Science
Added: August 6, 2018

1999 article

Terrestrial organic carbon accumulation on the Amazon deep sea fan during the last glacial sea level low stand

Schlunz, B., Schneider, R. R., Muller, P. J., Showers, W. J., & Wefer, G. (1999, July 8). CHEMICAL GEOLOGY, Vol. 159, pp. 263–281.

By: B. Schlunz*, R. Schneider*, P. Muller*, W. Showers n & G. Wefer*

author keywords: Amazon fan; terrestrial organic carbon; sea level; accumulation budget
UN Sustainable Development Goal Categories
13. Climate Action (Web of Science)
14. Life Below Water (OpenAlex)
Source: Web Of Science
Added: August 6, 2018

1998 journal article

The thermoregulatory functions of the Triceratops frill and horns: Heat flow measured with oxygen isotopes

JOURNAL OF VERTEBRATE PALEONTOLOGY, 18(4), 746–750.

By: R. Barrick n, M. Stoskopf n, J. Marcot *, D. Russell n & W. Showers n

TL;DR: The frill and horn cores of Triceratops were used as thermoregulatory structures with the horn cores interpreted as being especially important in the stabilization of brain temperatures at extreme ambient temperatures and the frill serving a more consistent role in body temperature regulation. (via Semantic Scholar)
UN Sustainable Development Goal Categories
15. Life on Land (Web of Science)
Source: Web Of Science
Added: August 6, 2018

1997 journal article

A pervasive millennial-scale cycle in North Atlantic Holocene and glacial climates

SCIENCE, 278(5341), 1257–1266.

By: G. Bond n, W. Showers n, M. Cheseby n, R. Lotti n, P. Almasi n, P. deMenocal  n, P. Priore n, H. Cullen n, I. Hajdas n, G. Bonani n

UN Sustainable Development Goal Categories
13. Climate Action (Web of Science)
Source: Web Of Science
Added: August 6, 2018

1997 journal article

Isotopic stratigraphy of Amazon fan sediments

Proceedings of the Ocean Drilling Program, 155(1997), 281–303.

By: W. Showers, R. Schneider, N. Mikkelson & M. Maslin

Source: NC State University Libraries
Added: August 6, 2018

1984 journal article

PRIMARY PRODUCTIVITY AND PARTICLE FLUXES ON A TRANSECT OF THE EQUATOR AT 153-DEGREES-W IN THE PACIFIC-OCEAN

DEEP-SEA RESEARCH PART A-OCEANOGRAPHIC RESEARCH PAPERS, 31(1), 1–11.

By: P. Betzer*, W. Showers n, E. Laws *, C. Winn*, G. Ditullio * & P. Kroopnick*

UN Sustainable Development Goal Categories
13. Climate Action (Web of Science)
14. Life Below Water (Web of Science)
Source: Web Of Science
Added: August 6, 2018

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