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The double helium-white dwarf channel for the formation of AM cVn binaries

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Research in Astronomy and Astrophysics 2018年第1期18卷 101-112页

作者： Xian-Fei Zhang Jin-Zhong Liu c.Simon jeffery Philip D.Hall Shao-Lan Bi Department of Astronomy Beijing Normal University Xinjiang Astronomical Observatory Chinese Academy of Sciences Armagh Observatory and Planetarium College Hill School of Physics Trinity College Dublin

Most close double helium white dwarfs will merge within a Hubble time due to orbital decay by gravitational wave ***,a significant fraction with low mass ratios will survive for a long time as a consequence of stable mass *** stable mass transfer between two helium white dwarfs（He WDs） provides one channel for the production of AM cVn binary *** previous calculations of double He WD progenitors,the accreting He WD was treated as a point *** have computed the evolution of 16 double He WD models in order to investigate the consequences of treating the evolution of both components in *** find that the boundary between binaries having stable and unstable mass transfer is slightly modified by this *** comparing with observed periods and mass ratios,we redetermine masses of eight known AM cVn stars by our double He WDs channel,*** cnc,AM cVn,V406 Hya,J0926,J1240,GP com,Gaia14 aae and V396 *** propose that central spikes in the triple-peaked emission spectra of J1240,GP com and V396 Hya and the surface abundance ratios of N/c/O in GP com can be explained by the stable double He WD *** mass estimates derived from our calculations are used to discuss the predicted gravitational wave signal in the context of the Laser Interferometer Space Antenna（LISA） project.

关键词： stars:peculiar(helium) stars:white dwarfs binaries:close gravitational waves

Antipoisoning catalysts for the selective oxygen reduction reaction at the interface between metal nanoparticles and the electrolyte

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carbon Energy 2023年第7期5卷 57-69页

作者： Sourabh S.chougule A.Anto jeffery Sreya Roy chowdhury Jiho Min Yunjin Kim Keonwoo Ko Bathinapatla Sravani Namgee Jung Graduate School of Energy Science and Technology(GEST) Chungnam National UniversityYuseong-guDaejeonRepublic of Korea

One of the primary challenges in relation to phosphoric acid fuel cells is catalyst poisoning by phosphate anions that occurs at the interface between metal nanoparticles and the *** strong adsorption of phosphate anions on the catalyst surface limits the active sites for the oxygen reduction reaction(ORR),significantly deteriorating fuel cell ***,antipoisoning catalysts consisting of Pt-based nanoparticles encapsulated in an ultrathin carbon shell that can be used as a molecular sieve layer are rationally *** pore structure of the carbon shells is systematically regulated at the atomic level by high-temperature gas treatment,allowing O_(2) molecules to selectively react on the active sites of the metal nanoparticles through the molecular ***,the carbon shell,as a protective layer,effectively prevents metal dissolution from the catalyst during a long-term ***,the defect-controlled carbon shell leads to outstanding ORR activity and durability of the hybrid catalyst even in phosphoric acid electrolytes.

关键词： carbon shell catalyst poisoning effect molecular sieve effect oxygen reduction reaction phosphate anions phosphoric acid fuel cells

ADDITIVE-INDUcED ENHANcEMENT OF OPTIcAL cLARITY OF POLYAcRYLAMIDE HYDROGEL

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chinese Journal of Polymer Science 2003年第5期21卷 533-539页

作者： jeffery Franklin Department of chemistry Carleton University 1125 Colonel By Drive Ottawa Ontario Canada KIS 5B6

The aqueous polymerization of acrylamide and crosslinking with N,N-methylenebisacrylamide afforded hydrogelsdisplaying high levels of light scattering (poor optical clarity). Enhancement of the optical clarity within a polyacrylamide(PAm) hydrogel was accomplished through the implementation of 'refractive index matching'. Water-soluble additives wereutilised to better match the refractive index inhomogeneities throughout a given hydrogel. This resulted in lower lightscattering within the system and hence improved clarity. Amino acids, sugars, polymers, and other water-soluble additivessuch as glycerol were investigated by this methodology. Most additives investigaed displayed potential for effectivelyreducing the light scattering within a PAm hydrogel as a function of increased additive concentration. On increasing therefractive index of the water medium, the overall refractive index of a PAm hydrogel was also observed to increase. Thisprovided a quantitative means of determining the effectiveness of a given additive for improving the optical clarity within ahydrogel.

关键词： Optical clarity Polyacrylamide hydrogel Refractive index matching Bacteriorhodopsin Optical memory device

Species distribution modeling in regions of high need and limited data： waterfowl of china

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Avian Research 2018年第1期9卷 49-62页

作者： Diann J.Prosser changqing Ding R.Michael Erwin Taej Mundkur jeffery D.Sullivan Erle c.Ellis Patuxent Wildlife Research center U.S. Geological Survey Beltsville MD 20705 USA University of Maryland College Park MD 20742 USA college of Nature conservation Beijing Forestry University Beijing 100083 China University of Virginia Charlottesville VA 22904 USA Wetlands International Horapark9 Ede 6717 LZ The Netherlands Natural Systems Analysts Winter Park FL 32789 USA Department of Geography and Environmental Systems University of Maryland Baltimore County Baltimore MD 21250 USA

Background: A number of conservation and societal issues require understanding how species are distributed on the landscape, yet ecologists are often faced with a lack of data to develop models at the resolution and extent desired, resulting in inefficient use of conservation *** a situation presented itself in our attempt to develop waterfowl distribution models as part of a multi-disciplinary team targeting the control of the highly pathogenic H5N1 avian influenza virus in ***: Faced with limited data, we built species distribution models using a habitat suitability approach for china's breeding and non-breeding(hereafter, wintering) *** extensive review of the literature was used to determine model parameters for habitat *** relationships were implemented in GIS using land cover *** models were validated using waterfowl census data, while breeding models, though developed for many species, were only validated for the one species with sufficient telemetry data ***: We developed suitability models for 42 waterfowl species(30 breeding and 39 wintering) at 1 km resolution for the extent of china, along with cumulative and genus level species richness *** season models showed highest waterfowl suitability in wetlands of the high-elevation west-central plateau and northeastern *** waterfowl suitability was highest in the lowland regions of southeastern *** measures indicated strong performance in predicting species *** our model outputs to china's protected areas indicated that breeding habitat was generally better covered than wintering habitat, and identified locations for which additional research and protection should be ***: These suitability models are the first available for many of china's waterfowl species, and have direct utility to conservation and habitat planning and prioritizing management of critically important

关键词： Anatidae Avian influenza china Habitat suitability H5N1 Spatial analysis Species distribution models Waterfowl

ON THE MODIFIED NONLINEAR ScHRDINGER EQUATION IN THE SEMIcLASSIcAL LIMIT:SUPERSONIc,SUBSONIc,AND TRANSSONIc BEHAVIOR

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Acta Mathematica Scientia 2011年第6期31卷 2343-2377页

作者： jeffery c. DiFranco Peter D. Miller Benson K. Muite Department of Mathematics Seattle University Department of Mathematics University of Michigan

The purpose of this paper is to present a comparison between the modified nonlinear SchrSdinger （MNLS） equation and the focusing and defocusing variants of the （unmodified） nonlinear SchrSdinger （NLS） equation in the semiclassical limit. We describe aspects of the limiting dynamics and discuss how the nature of the dynamics is evident theoretically through inverse-scattering and noncommutative steepest descent methods. The main message is that, depending on initial data, the MNLS equation can behave either like the defocusing NLS equation, like the focusing NLS equation （in both cases the analogy is asymptotically accurate in the semiclassical limit when the NLS equation is posed with appropriately modified initial data）, or like an interesting mixture of the two. In the latter case, we identify a feature of the dynamics analogous to a sonic line in gas dynamics, a free boundary separating subsonic flow from supersonic flow.

关键词： semiclassical limits dispersionless limits modulational instability focusing,defocusing, and modified nonlinear SchrSdinger equations

Establishment of highly efficient transgenic system for black soldier fly(Hermetia illucens)

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Insect Science 2023年第4期30卷 888-900页

作者： Zongqing Kou Xingyu Luo Yuguo Jiang Bihui chen Yu Song Yaohui Wang Jun Xui jeffery K.Tomberlin Yongping Huang Key Laboratory of Insect Developmental and Evolutionary Biology Center for Excellence in Molecular Plant SciencesShanghai Insttute of Plant Physiology and EcologyChinese Academy of SciencesShanghaiChina University of chinese Academy of Sciences BeijingChina Department of Entomology Texas A&M UniversityCollege StationTXUSA

The black soldier fly(BSF),Hermetia illucens,is a promising insect for miti-gating solid waste problems as its larvae are able to bioconvert organic waste into valuable *** recently reported a high-quality genome assembly of the BSF;analysis of this genome sequence will further the understanding of insect biology and identify genes that can be manipulated to improve efficiency of *** enable genetic manip-ulation of the BSF,we have established the first transgenic methods for this economically important *** cloned and identified the ubiquitous actin5c promoter(Hiactin5c-p3k)and 3 endogenous U6 promoters(HiU6:1,HiU6:2,and HiU6:3).The Hiactin5c pro-moter was used to drive expression of a hyperactive variant of the piggyBac transposase,which exhibited up to 6-fold improvement in transformation rate when compared to the wild-type ***,we evaluated the 3 HiU6 promoters using this trans-genic ***6:1 and HiU6:2 promoters provided the highest knockdown efficiency with RNAi and are thus promising candidates for future clustered Regularly Interspaced Short Palindromic Repeats(cRISPR)***,our findings provide valuable genetic engineering toolkits for basic research and genetic manipulation of the BSF.

关键词： actin5c promoter black soldier fly hyPBase transgenesis U6 promoter

Assessing nest attentiveness of common Terns via video cameras and temperature loggers

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Avian Research 2020年第3期11卷 284-301页

作者： jeffery D.Sullivan Paul R.Marbán Jennifer M.Mullinax David F.Brinker Peter c.McGowan carl R.callahan Diann J.Prosser Natural Systems Analysts Winter ParkFL 32789USA Marine Estuarineand Environmental Sciences ProgramUniversity of MarylandCollege ParkMD 20742USA Department of Environmental Science and Technology University of Maryland1443 Animal Sciences BldgCollege ParkMD 20742USA Department of Natural Resources Maryland Natural Heritage ProgramAnnapolisMD 21401USA chesapeake Bay Field Office U.S.Fish and Wildlife ServiceAnnapolisMD 21401USA U.S.Geological Survey Patuxent Wildlife Research CenterLaurelMD 20708USA.

Background:While nest attentiveness plays a critical role in the reproductive success of avian species,nest attentiveness data with high temporal resolution is not available for many ***,improvements in both video monitoring and temperature logging devices present an opportunity to increase our understanding of this aspect of avian ***:To investigate nest attentiveness behaviors and evaluate these technologies,we monitored 13 nests across two common Tern(Sterna hirundo)breeding colonies with a paired video camera-temperature logger approach,while monitoring 63 additional nests with temperature loggers *** occurred from May to August of 2017 on Poplar(chesapeake Bay,Maryland,USA)and Skimmer Islands(Isle of Wight Bay,Maryland,USA).We examined data respective to four times of day:Morning(civil dawn‒11:59),Peak(12:00‒16:00),cooling(16:01‒civil dusk),and Night(civil dusk‒civil dawn).Results:While successful nests had mostly short duration off-bouts and maintained consistent nest attentiveness throughout the day,failed nests had dramatic reductions in nest attentiveness during the cooling and Night periods(pcolony experiencing repeated nocturnal abandonment due to predation pressure from a Great Horned Owl(Bubo virginianus).Incubation appeared to ameliorate ambient temperatures during Night,as nests were significantly warmer during Night when birds were on versus off the nest(pccurred during higher ambient temperatures,perhaps due to adults leaving the nest during the hottest periods to perform belly ***,temperature logger data alone had limited ability to predict nest attentiveness status during shorter bouts,with results highly dependent on time of day and bout *** our methods did not affect hatching success(p>0.05),video-monitored nests did have significantly lower clutch sizes(pconclusions:The paired use of iButtons and video ca

关键词： common Tern iButton Nest attentiveness Sterna hirundo Temperature logger Video monitoring

Increased oxygen consumption and OXPHOS potential in superhealer mesenchymal stem cells

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cell Regeneration 2012年第1期1卷 11-18页

作者： curtis c Hughey Maria P Alfaro Darrell D Belke jeffery N Rottman Pampee P Young David H Wasserman Jane Shearer Department of Biochemistry and Molecular Biology Faculty of MedicineUniversity of CalgaryCalgaryABCanadaT2N 1N4 Department of Pathology School of MedicineVanderbilt UniversityNashvilleTNUSA37232 Faculty of Kinesiology University of CalgaryCalgaryABCanadaT2N 1N4 Department of Medicine Division of Cardiovascular MedicineSchool of MedicineVanderbilt UniversityNashvilleTNUSA37240 Department of Veterans Affairs Medical center NashvilleTNUSA37232 Department of Molecular Physiology and Biophysics School of MedicineVanderbilt UniversityNashvilleTNUSA37240 University of calgary KNB Rm 3318.2500 University Dr.NWCalgaryABCanadaT2N 1N4.

Background:cell-based therapies show promise in repairing cardiac tissue and improving contractile performance following a myocardial *** this,ischemia-induced death of transplanted cells remains a major hurdle to the efficacy of treatment.‘Superhealer’MRL/MpJ mesenchymal stem cells(MRL-MScs)have been reported to exhibit increased engraftment resulting in reduced infarct size and enhanced contractile *** study determines whether intrinsic differences in mitochondrial oxidative phosphorylation(OXPHOS)assist in explaining the enhanced cellular survival and engraftment of ***:compared to wild type MScs(WT-MScs),mitochondria from intact MRL-MScs exhibited an increase in routine respiration and maximal electron transport capacity by 2.0-and 3.5-fold,*** routine oxygen utilization is expressed as a portion of maximal cellular oxygen flux,the MRL-MScs have a greater spare respiratory ***,glutamate/malate-and succinate-supported oxygen consumption in permeabilized cells was elevated approximately 1.25-and 1.4-fold in the MRL-MScs,***:The results from intact and permeabilized MScs indicate MRL-MScs exhibit a greater reliance on and capacity for aerobic *** greater capacity for oxidative metabolism may provide a protective effect by increasing ATP synthesis per unit substrate and prevent glycolysis-mediated acidosis and subsequent cell death upon transplantation into the glucose-and oxygen-deprived environment of the infarcted heart.

关键词： Energetics Mitochondria Oxidative phosphorylation Stem cells

Effect of drought stress on male fertility restoration in A3 cMS-inducing cytoplasm of sorghum

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The crop Journal 2017年第4期5卷 282-289页

作者： Valentin V.Kozhemyakin Lev A.Elkonin jeffery A.Dahlberg Department of Biotechnology Agricultural Research Institute of South-East Region Tulaikov Street 7 Saratov 410010 Russia Kearney Agricultural Research & Extension (KARE) 9240 South Riverbend Avenue Parlier CA 93648 USA

Use of cytoplasmic male sterility (cMS) in hybrid breeding requires effective male fertility-restoring lines. In sorghum, very few restoring lines that can restore fertility in A_3 cMS have been reported. To identify the reasons for this deficiency, F_1 and F_2 hybrids of an A_3 cMS line crossed with the line IS1112c, a donor of fertility-restoring (Rf) genes for A_3 cytoplasm, and testcrosses of fertile plants to A_3cMS lines were grown under contrasting water availability regimes in dryland and irrigated field plots. In the irrigated plots the frequency of fertile plants in testcrosses was twice that in dryland plots (P lots showed significantly higher restoration ability than fertile plants from the same family grown in dryland plots. F_3 plants from the F_2 family grown in irrigated plots yielded on average a sixfold higherfrequency of fertile plants in testcrosses than F_3 plants derived from dryland plots (P cross hybrids correlated negatively with air vapor pressure deficit (VPD) at flowering (r = - 0.96; P cytoplasm.

关键词： Sorghum bicolor (L.) Moench cytoplasmic male sterility A3 cytoplasm Fertility-restoring genes Epigenetics Vapor pressure deficit