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Full-Text Articles in Physical Sciences and Mathematics

Evaluating Artificial Shelter Arrays As A Minimally Invasive Monitoring Tool For The Hellbender Cryptobranchus Alleganiensis, Catherine M. Bodinof Jachowski, Beth E. Ross, William A. Hopkins Feb 2020

Evaluating Artificial Shelter Arrays As A Minimally Invasive Monitoring Tool For The Hellbender Cryptobranchus Alleganiensis, Catherine M. Bodinof Jachowski, Beth E. Ross, William A. Hopkins

Publications

Hellbenders Cryptobranchus alleganiensis are critically imperiled amphibians throughout the eastern USA. Rock-lifting is widely used to monitor hellbenders but can severely disturb habitat. We asked whether artificial shelter occupancy (the proportion of occupied shelters in an array) would function as a proxy for hellbender abundance and thereby serve as a viable alternative to rock-lifting. We hypothesized that shelter occupancy would vary spatially in response to hellbender density, natural shelter density, or both, and would vary temporally with hellbender seasonal activity patterns and time since shelter deployment. We established shelter arrays (n = 30 shelters each) in 6 stream reaches and …


Developing A Monthly Radiative Kernel For Surface Albedo Change From Satellite Climatologies Of Earth's Shortwave Radiation Budget: Cack V1.0, Ryan M. Bright, Thomas L. O'Halloran Sep 2019

Developing A Monthly Radiative Kernel For Surface Albedo Change From Satellite Climatologies Of Earth's Shortwave Radiation Budget: Cack V1.0, Ryan M. Bright, Thomas L. O'Halloran

Publications

Due to the potential for land-use–land-cover change (LULCC) to alter surface albedo, there is need within the LULCC science community for simple and transparent tools for predicting radiative forcings (ΔF) from surface albedo changes (Δαs). To that end, the radiative kernel technique – developed by the climate modeling community to diagnose internal feedbacks within general circulation models (GCMs) – has been adopted by the LULCC science community as a tool to perform offline ΔF calculations for Δαs. However, the codes and data behind the GCM kernels are not readily transparent, and the climatologies …


Expanding Beyond Carnivores To Improve Livestock Protection And Conservation, Shari L. Rodriguez, Christie Sampson Aug 2019

Expanding Beyond Carnivores To Improve Livestock Protection And Conservation, Shari L. Rodriguez, Christie Sampson

Publications

Promoting human–wildlife coexistence is critical to the long-term conservation of many wild animal species that come into conflict with humans. Loss of livestock to carnivore species (e.g., lions, tigers, wolves) is a well-documented occurrence and the focus of mitigation strategies around the world. One area that has received little research is the impact of noncarnivores on livestock. Both African and Asian elephant species are known to cause livestock injuries and deaths. Livestock owners within elephant ranges perceive elephants as a risk to their livestock, which may reduce their tolerance towards elephants and jeopardize conservation efforts in the area. Though feral …


Rapid Screening Of Ellagitannins In Natural Sources Via Targeted Reporter Ion Triggered Tandem Mass Spectrometry, Jeremiah J. Bowers, Harsha P. Gunawardena, Anaëlle Cornu, Ashwini S. Narvekar, Antoine Richieu, Denis Deffieux, Stéphane Quideau, Nishanth Tharayil Jul 2018

Rapid Screening Of Ellagitannins In Natural Sources Via Targeted Reporter Ion Triggered Tandem Mass Spectrometry, Jeremiah J. Bowers, Harsha P. Gunawardena, Anaëlle Cornu, Ashwini S. Narvekar, Antoine Richieu, Denis Deffieux, Stéphane Quideau, Nishanth Tharayil

Publications

Complex biomolecules present in their natural sources have been difficult to analyze using traditional analytical approaches. Ultrahigh-performance liquid chromatography (UHPLC-MS/MS) methods have the potential to enhance the discovery of a less well characterized and challenging class of biomolecules in plants, the ellagitannins. We present an approach that allows for the screening of ellagitannins by employing higher energy collision dissociation (HCD) to generate reporter ions for classification and collision-induced dissociation (CID) to generate unique fragmentation spectra for isomeric variants of previously unreported species. Ellagitannin anions efficiently form three characteristic reporter ions after HCD fragmentation that allows for the classification of unknown …


Correlation Of Trichome Density And Length And Polyphenol Fluorescence With Susceptibility Of Five Cucurbits To Didymella Bryoniae, Gabriel Rennberger, A. P. Keinath, M. Hess Aug 2017

Correlation Of Trichome Density And Length And Polyphenol Fluorescence With Susceptibility Of Five Cucurbits To Didymella Bryoniae, Gabriel Rennberger, A. P. Keinath, M. Hess

Publications

The fungal pathogen Didymella bryoniae causes gummy stem blight and black rot on a broad spectrum of cucurbits. However the substantial differences in susceptibility among Cucurbitaceae are not well studied. Susceptibility was characterized with muskmelon (Cucumis melo), watermelon (Citrullus lanatus), cucumber (Cucumis sativus), pumpkin (Cucurbita pepo), and zucchini (C. pepo). Lesion diameters on leaf disks inoculated with agar plugs were measured 7 days after inoculation, and the necrotized areas of leaf disks inoculated with conidial suspensions were measured 48 h after inoculation (hai). For each species, the number of trichomes …


A Revision Of Prespelea Park (Staphylinidae, Pselaphinae), Michael S. Caterino, Laura M. Vásquez-Vélez Jul 2017

A Revision Of Prespelea Park (Staphylinidae, Pselaphinae), Michael S. Caterino, Laura M. Vásquez-Vélez

Publications

We revise the genus Prespelea Park, redefining and redescribing the two previously known species, P.copelandi Park and P. quirsfeldi Park, and adding ten new species: P. parki Caterino & Vásquez-Vélez, sp. n., P.minima Caterino & Vásquez-Vélez, sp. n., P. morsei Caterino & Vásquez-Vélez, sp. n., P. divergens Caterino & Vásquez-Vélez, sp. n., P. carltoni Caterino & Vásquez-Vélez, sp. n., P. myersae Caterino & Vásquez-Vélez, sp. n., P. georgiensis Caterino & Vásquez-Vélez, sp. n., P. enigma Caterino & Vásquez-Vélez, sp. n., P. wagneriCaterino & Vásquez-Vélez, sp. n., and P. basalis Caterino …


Exchange Of Polar Lipids From Adults To Neonates In Daphnia Magna: Perturbations In Sphingomyelin Allocation By Dietary Lipids And Environmental Toxicants, Namrata Sengupta, Delaney C. Reardon, Patrick D. Gerard, William S. Baldwin May 2017

Exchange Of Polar Lipids From Adults To Neonates In Daphnia Magna: Perturbations In Sphingomyelin Allocation By Dietary Lipids And Environmental Toxicants, Namrata Sengupta, Delaney C. Reardon, Patrick D. Gerard, William S. Baldwin

Publications

Because xenosensing nuclear receptors are also lipid sensors that regulate lipid allocation, we hypothesized that toxicant-induced modulation of HR96 activity would alter lipid profiles and the balance between adult survival and neonate production following exposure in Daphnia magna. Adult daphnids were exposed to unsaturated fatty acid- and toxicant- activators or inhibitors of HR96 and later starved to test whether chemical exposure altered allocation toward survival or reproduction. The HR96 activators, linoleic acid and atrazine, decreased reproduction as expected with concomitant changes in the expression of HR96 regulated genes such as magro. The HR96 inhibitors, docosahexaenoic acid (DHA) and triclosan, …


A Revision Of Megalocraerus Lewis, 1902 (Coleoptera, Histeridae: Exosternini), Michael S. Caterino, Alexey K. Tishechkin Jan 2016

A Revision Of Megalocraerus Lewis, 1902 (Coleoptera, Histeridae: Exosternini), Michael S. Caterino, Alexey K. Tishechkin

Publications

The formely monotypic Neotropical genus Megalocraerus Lewis is revised to include five species, known from southeastern Brazil to Costa Rica: M. rubricatus Lewis, M. mandibularis sp. n., M. chico sp. n., M. madrededios sp. n., and M. tiputini sp. n. We describe the species, map their distributions, and provide a key for their identification. Their subcylindrical body form and emarginate mesosternum have previously hindered placement to tribe, although their curent assignment to Exosternini now appears well supported by morphological evidence. Nothing is known of the natural history of the species.


Wind Damage And Salinity Effects Of Hurricanes Katrina And Rita On Coastal Baldcypress Forests Of Louisiana, William Conner, Thomas W. Doyle, Richard H. Day, Ken W. Krauss, Christopher M. Swarzenski Jan 2007

Wind Damage And Salinity Effects Of Hurricanes Katrina And Rita On Coastal Baldcypress Forests Of Louisiana, William Conner, Thomas W. Doyle, Richard H. Day, Ken W. Krauss, Christopher M. Swarzenski

Publications

The frequency of hurricane landfall in a given coastal stretch may play a more important role in the ecology of coastal forests than previously thought because of direct and indirect impacts of fallen trees and the introduction of salt water that lingers long after the storm passes. Findings show that surge events can inundate interior freshwater forests many miles from the coast and elevate soil salinities twofold to threefold. These elevated salinities may contribute to delayed mortality of certain tree species and set the stage for eventual forest decline and dieback.


Science And The Storms: The Usgs Response To The Hurricanes Of 2005 - Chapter Six: Ecological Impacts, William Conner, Stephen Faulkner, Wylie Barrow, Brady Couvillion, Lori Randall, Michael Baldwin Jan 2007

Science And The Storms: The Usgs Response To The Hurricanes Of 2005 - Chapter Six: Ecological Impacts, William Conner, Stephen Faulkner, Wylie Barrow, Brady Couvillion, Lori Randall, Michael Baldwin

Publications

Ecological impacts from the hurricanes of 2005 affected both vegetation and the animals that depend on coastal habits on land and in water. Discussed in this section are migratory birds, coastal marsh vegetation, chenier forests, coastal floodplain forests, mangrove forests, estuaries, and the endangered manatee.


Characterization Of An Isolate That Uses Vinyl Chloride As A Growth Substrate Under Aerobic Conditions, Matthew F. Verce, Ricky L. Ulrich, David L. Freedman Aug 2000

Characterization Of An Isolate That Uses Vinyl Chloride As A Growth Substrate Under Aerobic Conditions, Matthew F. Verce, Ricky L. Ulrich, David L. Freedman

Publications

An aerobic enrichment culture was developed by using vinyl chloride (VC) as the sole organic carbon and electron donor source. VC concentrations as high as 7.3 mM were biodegraded without apparent inhibition. VC use did not occur when nitrate was provided as the electron acceptor. A gram-negative, rod-shaped, motile isolate was obtained from the enrichment culture and identified based on biochemical characteristics and the sequence of its 16S rRNA gene as Pseudomonas aeruginosa, designated strain MF1. The observed yield of MF1 when it was grown on VC was 0.20 mg of total suspended solids (TSS)/mg of VC. Ethene, acetate, glyoxylate, …


Enhanced Biotransformation Of Carbon Tetrachloride By Acetobacterium Woodii Upon Addition Of Hydroxocobalamin And Fructose, Syed A. Hashsham, David L. Freedman Oct 1999

Enhanced Biotransformation Of Carbon Tetrachloride By Acetobacterium Woodii Upon Addition Of Hydroxocobalamin And Fructose, Syed A. Hashsham, David L. Freedman

Publications

The objective of this study was to evaluate the effect of hydroxocobalamin (OH-Cbl) on transformation of high concentrations of carbon tetrachloride (CT) by Acetobacterium woodii (ATCC 29683). Complete transfor-mation of 470 􀀀M (72 mg/liter [aqueous]) CT was achieved by A. woodii within 2.5 days, when 10 􀀀M OH-Cbl was added along with 25.2 mM fructose. This was approximately 30 times faster than A. woodii cultures (live or autoclaved) and medium that did not receive OH-Cbl and 5 times faster than those controls that did receive OH-Cbl, but either live A. woodii or fructose was missing. CT transformation in treatments with …


Reduction And Acetylation Of 2,4-Dinitrotoluene By A Pseudomonas Aeruginosa Strain, Daniel R. Noguera, David L. Freedman Jul 1996

Reduction And Acetylation Of 2,4-Dinitrotoluene By A Pseudomonas Aeruginosa Strain, Daniel R. Noguera, David L. Freedman

Publications

Aerobic and anoxic biotransformation of 2,4-dinitrotoluene (DNT) was examined by using a Pseudomonas aeruginosa strain isolated from a plant treating propellant manufacturing wastewater. DNT biotransformation in the presence and absence of oxygen was mostly reductive and was representative of the type of cometabolic transformations that occur when a high concentration of an easily degradable carbon source is present. P. aeruginosa reduced both nitro groups on DNT, with the formation of mainly 4-amino-2-nitrotoluene and 2-amino-4-nitrotoluene and small quantities of 2,4-diaminotoluene. Acetylation of the arylamines was a significant reaction. 4-Acetamide-2-nitrotoluene and the novel compounds 2-acetamide-4-nitrotoluene, 4-acet-amide-2-aminotoluene, and 2,4-diacetamidetoluene were identified as DNT …


Biodegradation Of Dichloromethane And Its Utilization As A Growth Substrate Under Methanogenic Conditions, David L. Freedman, James M. Gossett Oct 1991

Biodegradation Of Dichloromethane And Its Utilization As A Growth Substrate Under Methanogenic Conditions, David L. Freedman, James M. Gossett

Publications

Biodegradation of dichloromethane (DCM) to environmentally acceptable products was demonstrated under methanogenic conditions (35 degrees C). When DCM was supplied to enrichment cultures as the sole organic compound at a low enough concentration to avoid inhibition of methanogenesis, the molar ratio of CH4 formed to DCM consumed (0.473) was very close to the amount predicted by stoichiometric conservation of electrons. DCM degradation was also demonstrated when methanogenesis was partially inhibited (with 0.5 to 1.5 mM 2-bromoethanesulfonate or approximately 2 mM DCM) or completely stopped (with 50 to 55.5 mM 2-bromoethanesulfonate). Addition of a eubacterial inhibitor (vancomycin, 100 mg/liter) greatly reduced …


Biological Reductive Dechlorination Of Tetrachloroethylene And Trichloroethylene To Ethylene Under Methanogenic Conditions, David L. Freedman, James M. Gossett Sep 1989

Biological Reductive Dechlorination Of Tetrachloroethylene And Trichloroethylene To Ethylene Under Methanogenic Conditions, David L. Freedman, James M. Gossett

Publications

A biological process for remediation of groundwater contaminated with tetrachloroethylene (PCE) and trichloroethylene (TCE) can only be applied if the transformation products are environmentally acceptable. Studies with enrichment cultures of PCE- and TCE-degrading microorganisms provide evidence that, under methanogenic conditions, mixed cultures are able to completely dechlorinate PCE and TCE to ethylene, a product which is environmentally acceptable. Radiotracer studies with [14C]PCE indicated that [14C]ethylene was the terminal product; significant conversion to 14CO2 or 14CH4 was not observed. The rate-limiting step in the pathway appeared to be conversion of vinyl chloride to ethylene. To sustain reductive dechlorination of PCE and …