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Influence of free water availability on a desert carnivore and herbivore

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Current Zoology 2017年第2期63卷 121-129页

作者： Bryan m. KLUEVER Eric m. GESE steven j. DEmPSEY Department of Wildland Resources Utah State University Logan UT 84322-5230 USA United States Department of Agriculture Animal and Plant Health Inspection Service Wildlife Services National Wildlife Research Center Department of Wildland Resources Utah State University Logan UT 84322-5230 USA

Anthropogenic manipulation of finite resources on the landscape to benefit individual species or communities is commonly employed by conservation and management agencies. One such action in arid regions is the construction and maintenance of water developments （i.e., wildlife guzzlers） adding free water on the landscape to buttress local populations, influence animal movements, or af- fect distributions of certain species of interest. Despite their prevalence, the utility of wildlife guzzlers remains largely untested. We employed a before-after control-impact （BACI） design over a 4-year period on the US Army Dugway Proving Ground, Utah, USA, to determine whether water avaijability at wildlife guzzlers influenced relative abundance of black-tailed jackrabbits Lepus californicus and relative use of areas near that resource by coyotes Canis latrans, and whether coyote visitations to guzzlers would decrease following elimination of water. Eliminating water availability at guzzlers did not influence jackrabbit relative abundance. Coyote relative use was impacted by water availability, with elimination of water reducing use in areas associated with our treatment, but not with areas associated with our control. Visitations of radio-collared coyotes to guzzlers declined nearly 3-fold following elimination of water. Our study provides the first evidence of a potential direct effect of water sources on a mammalian carnivore in an arid environment, but the ecological relevance of our finding is debatable. Future investigations aimed at determining water effects on terrestrial mam- mals could expand on our findings by incorporating manipulations of water availability, obtaining absolute estimates of population parameters and vital rates and incorporating fine-scale spatiotem- poral data.

关键词： arid black-tailed jackrabbit Canis latrans coyote Lepus cafifornicus.

mate choice decisions by searchers

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Current Zoology 2013年第2期59卷 184-199页

作者： Daniel D. WIEGmANN Lisa m. ANGELONI steven m. SEUBERT j. GordonWADE Department of Biological Sciences and j. P. Scott Center for Neuroscience Mind and Behavior Bowling Green State University Bowling Green OH 43403 USA Department of Biology Colorado State University Fort Collins CO 80523 USA Department of mathematics and Statistics Bowling Green State University Bowling Green OH 43403 USA

For more than two decades rudimentary versions of the fixed sample and sequential search strategies have provided the primary theoretical foundation for the study of mate choice decisions by searchers. The theory that surrounds these models has expanded markedly over this time period. In this paper, we review and extend results derived from these models, with a focus on the empirical analysis of searcher behavior. The basic models are impractical for empirical purposes because they rely on the as- sumption that searchers--and, for applied purposes, researchers--assess prospective mates based on their quality, the fitness consequences of mate choice decisions. Here we expound versions of the models that are more empirically useful, reformulated to reflect decisions based on male phenotypic characters. For some organisms, it may be possible to use preference functions to de- rive predictions from the reformulated models and thereby avoid difficulties associated with the measurement of male quality per se. But predictions derived from the two models are difficult to differentiate empirically, regardless of how the models are formu- lated. Here we develop ideas that illustrate how this goal might be accomplished. In addition, we clarify how the variability of male quality should be evaluated and we extend what is known about how this variability influences searcher behavior under each model. more general difficulties associated with the empirical study of mate choice decisions by searchers are also discussed [Current Zoology 59 （2）： 184-199, 2013].

关键词： Dispersive order Fixed sample strategy mate choice Preference functions Sequential search Stochastic dominance

Benchmark Computations of the Phase Field Crystal and Functionalized Cahn-Hilliard Equations via Fully Implicit,Nesterov Accelerated Schemes

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Communications in Computational Physics 2023年第2期33卷 367-398页

作者： jea-Hyun Park Abner j.Salgado steven m.Wise Department of mathematics University of California Santa BarbaraCA 93106USA Department of mathematics University of Tennessee KnoxvilleTN 37996USA.

We introduce a fast solver for the phase field crystal(PFC)and functionalized Cahn-Hilliard(FCH)equations with periodic boundary conditions on a rectangular domain that features the preconditioned Nesterov’s accelerated gradient descent(PAGD)*** discretize these problems with a Fourier collocation method in space,and employ various second-order schemes in *** observe a significant speedup with this solver when compared to the preconditioned gradient descent(PGD)*** the PAGD solver,fully implicit,second-order-in-time schemes are not only feasible to solve the PFC and FCH equations,but also do so more efficiently than some semi-implicit schemes in some cases where accuracy issues are taken into *** computations of four different schemes for the PFC and FCH equations are conducted and the results indicate that,for the FCH experiments,the fully implicit schemes(midpoint rule and BDF2 equipped with the PAGD as a nonlinear time marching solver)perform better than their ImEX versions in terms of computational cost needed to achieve a certain *** the PFC,the results are not as conclusive as in the FCH experiments,which,we believe,is due to the fact that the nonlinearity in the PFC is milder nature compared to the FCH *** also discuss some practical matters in applying the *** introduce an averaged Newton preconditioner and a sweeping-friction strategy as heuristic ways to choose good preconditioner *** sweeping-friction strategy exhibits almost as good a performance as the case of the best manually tuned parameters.

关键词： Phase field crystal functionalized Cahn-Hilliard preconditioning Nesterov acceleration nonlinear solver.

The current trend of autologous costal cartilage harvest by facial plastic surgeons for rhinoplasty in the United States

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Plastic and Aesthetic Research 2019年第2期6卷 1-7页

作者： Clara m.Olcott steven j.Pearlman Inland Ear Nose&Throat-Facial Plastics UplandCA 91784USA Pearlman Aesthetic Surgery New YorkNY 10022USA

Aim: To assess the safety profile and practice trend of autologous costal cartilage harvest by facial plastic surgeons in the United States (US).methods: A 10-question online survey was distributed by the American Academy of Facial Plastic and Reconstructive Surgery to its ***: Of the 2,639 members, 2,379 received the survey with 137 (5.76%) members responded. The majority (33.6%)of the respondents were expert facial plastic surgeons. One hundred and nine (79.6%) of the respondents performed rib harvest with 49.6% of them performing the procedure at a hospital facility. Among them, 21.5% exclusively performed their surgery at an ambulatory surgical center not physically attached to a hospital while 6.67% of them at the in-office accredited operating room. When comparing techniques, 64.7% performed only full-thickness rib grafts vs. 12.0%harvesting partial-thickness rib grafts. most used an incision length between 2.1 and 4 cm (64.4%) while 2 surgeons used m incision. The occurrence of pneumothorax after autologous rib harvest remained low (most (73.1%).Regarding safety practices of the surgeons, only 24.6% would order a chest X-ray post-operatively while 54.5% would not. In addition, 58.7% of respondents never kept their patients overnight for observation after autologous rib grafting while 15.0% always would. For pain management, most respondents (50.4%) did not utilize any additional analgesia protocol besides oral pain ***: Two thirds of the US facial plastic surgeons performed autologous costal cartilage harvest in a hospital setting. Routine chest imaging or overnight observation post-operatively was not warranted as the percentage of pneumothorax remained low and pain control was adequate.

关键词： Rib graft autologous costal cartilage rhinoplasty current practice pneumothorax

Bacterial biota in reflux esophagitis and Barrett's esophagus

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World journal of Gastroenterology 2005年第46期11卷 7277-7283页

作者： Zhiheng Pei Liying Yang Richard m Peek jr steven m Levine David T Pride martin j Blaser Departments of Pathology and medicine New York University School of Medicine New York NY 10016 the United States of America and Department of Veterans Affairs New York Harbor Health System New York NY 10010United States Department of Pathology New York University School of Medicine New York NY 10016 United States jr Department of Medicine Vanderbilt University School of Medicine Nashville TN 37212United States Department of medicine New York University School of Medicine New York NY 10016 United States Departments of medicine and microbiology New York University School of Medicine New York NY 10016United States Departments of medicine and microbiology New York University School of Medicine New York NY 10016the United States of America and Department of Veterans AffairsNew York Harbor Health System New York NY 10010 United States

AIm： To identify the bacterial flora in conditions such as Barrett＇s esophagus and reflux esophagitis to determine if they are similar to normal esophageal flora. mETHODS： Using broad-range 16S rDNA PCR, esophageal biopsies were examined from 24 patients [9 with normal esophageal mucosa, 12 with gastroesophageal reflux disease （GERD）, and 3 with Barrett＇s esophagus]. Two separate broad-range PCR reactions were performed for each patient, and the resulting products were cloned. In one patient with Barrett＇s esophagus, 99 PCR clones were analyzed. RESULTS： Two separate clones were recovered from each patient （total = 48）, representing 24 different species, with 14 species homologous to known bacteria, 5 homologous to unidentified bacteria, and 5 were not homologous （〈97% identity） to any known bacterial 16S rDNA sequences. Seventeen species were found in the reflux esophagitis patients, 5 in the Barrett＇s esophagus patients, and 10 in normal esophagus patients. Further analysis concentrating on a single biopsy from an individual with Barrett＇s esophagus revealed the presence of 21 distinct bacterial species. members of four phyla were represented, including Bacteroidetes, Firmicutes, Proteobacteria, and Actinobacteria. microscopic examination of each biopsy demonstrated bacteria in intimate association with the distal esophageal epithelium, suggesting that the presence of these bacteria is not transitory. CONCLUSION： These findings provide evidence for a complex, residential bacterial population in esophageal reflux-related disorders. While much of this biota is present in the normal esophagus, more detailed comparisons may help identify potential disease associations.

关键词： Bacterial biota Esophagus 16S rDNA PCR

Loss of Hox5 function results in myofibroblast mislocalization and distal lung matrix defects during postnatal development

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Science China(Life Sciences) 2018年第9期61卷 1030-1038页

作者： steven m.Hrycaj Leilani marty-Santos ANDrew j.Rasky Nicholas W.Lukacs Deneen m.Wellik Department of Internal medicine Division of Molecular Medicine and Genetics University of Michigan Department of Pathology University of Michigan Department of Cell and Developmental Biology University of Michigan

Alveologenesis is the final stage of lung development and is responsible for the formation of the principle gas exchange units called alveoli. The lung mesenchyme, in particular the alveolar myofibroblasts, are drivers of alveolar development, however,few key regulators that govern the proper distribution and behavior of these cells in the distal lung during alveologenesis have been identified. While Hox5 triple mutants(Hox5 aabbcc) exhibit neonatal lethality, four-allele, compound mutant mice(Hox5 AabbCc) are born in mendelian ratios and are phenotypically normal at birth. However, they exhibit defects in alveologenesis characterized by a BPD-like phenotype by early postnatal stages that becomes more pronounced at adult stages. Invasive pulmonary functional analyses demonstrate significant increases in total lung volume and compliance and a decrease in elastance in Hox5 compound mutants. SmA+ myofibroblasts in the distal lung are distributed abnormally during peak stages of alveologenesis and aggregate, resulting in the formation of a disrupted elastin network. Examination of other key components of the distal lung ECm, as well as other epithelial cells and lipofibroblasts reveal no differences in distribution. Collectively, these data indicate that Hox5 genes play a critical role in alveolar development by governing the proper cellular behavior of myofibroblasts during alveologenesis.

关键词： Hox5 alveologenesis alveolar myofibroblasts lung ECm postnatal lung development

Determinants of the Specif icity of Protein Targeting to Chloroplasts or mitochondria

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molecular Plant 2019年第7期12卷 893-895页

作者： Lucas mcKinnon steven m.Theg Department of Plant Biology University of California Davis Davis CA USA

Chloroplasts and mitochondria are both thought to have arisen through primary endosymbiosis (Kutschera and Niklas, 2005). As each organelle evolved, most of its genome was transferred to the host nucleus resulting in the vast majority of its proteome being nuclear encoded and synthesized on cytosolic ribosomes (Shi and Theg, 2013).

关键词： Chloroplasts mitochondria

Characterizing downwind drift deposition of aerially applied glyphosate using RbCl as tracer

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International journal of Agricultural and Biological Engineering 2017年第3期10卷 31-36页

作者： Yanbo Huang Claudiane m.Ouellet-Plamondon steven j.Thomson Krishna N.Reddy United States Department of Agriculture Agricultural Research ServiceCrop Production Systems Research Unit141 Experiment Station RoadStonevilleMS 38776USA Department of Construction Engineering Superior Technology School1100 Notre-Dame Street WestMontrealQuebec H3C 1K3Canada United States Department of Agriculture National Institute of Food and AgriculturalDivision of Agricultural SystemsWaterfront Center80009th StreetSWWashingtonDC 20024USA

Rubidium chloride(RbCl)was used as a tracer tank-mixed with active ingredients to profile downwind deposition of aerially applied crop protection and production materials to characterize off-target drift,which helps improve spray efficiency and reduce environmental *** sheets were placed on a holder in the field at each sampling station to collect sprayed *** tracer was used to assess downwind drift of nozzles mounted on the booms installed and controlled on both sides of an agricultural *** experiment was conducted on a field covered by Bermuda grass(Cynodon dactylon).During the experiment,the airplane was planned to fly three passes with three replications at each of three different altitudes,3.7 m,4.9 m,and 6.1 m for total of 27 flight *** results indicated that sampling station location had a significant effect on RbCl ***,application release altitude was not significant to the change of *** practical application in the same aerial application system was used to assess crop injury from the off-target drift of aerially applied *** concentrations measured from mylar sheets were correlated with visual injury,plant height,shoot dry weight,leaf chlorophyll content,and shikimate,which were measured from the leaves and plant samples ***,RbCl is an effective tracer for monitoring spray applications from agricultural aircraft and unmanned aerial vehicles to intensify agriculture output and minimize environmental impact.

关键词： Rubidium chloride(RbCl) precision agriculture spray efficiency off-target drift aerial application herbicide crop injury environmental pollution

Trends and seasonality in hospitalizations for acute alcohol-related and biliary pancreatitis in the USA

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Hepatobiliary & Pancreatic Diseases International 2021年第2期20卷 173-181页

作者： Artem Shmelev Anne m Sill Tiffany Horrigan steven C Cunningham Department of Surgery Saint Agnes HealthcareBaltimoreMDUSA

Background:The incidence of acute pancreatitis(AP)is characterized by circannual and geographical *** aim of this study was to describe seasonal variation and trends in hospitalizations for AP in the USA with respect to AP ***:The Nationwide Inpatient Sample data(2000–2016)from the Healthcare Cost and Utilization Project were *** study population included all primary hospitalizations for *** AP(BAP)and alcohol-induced AP(AAP)were distinguished by diagnostic and procedural ICD *** trend decomposition was ***:There was a linear increase in annual incidence(per 100000 population)of AAP in the USA(from 17.0 in 2000 to 22.9 in 2016),while incidence of BAP,equaled 19.9 in 2000,peaked at 22.1 in 2006 and decreased to 17.4 in *** incidence demonstrated 18%annual incidence amplitude with summer peak and winter trough,more prominent in *** 2016,within AAP,the highest incidence(per 100000 population)was noted among African-Americans(up to 50.4),followed by males aged 56–70 years(26.5)and Asians of low income(25.5);within BAP,above the average incidence was observed in Hispanic(up to 25.8)and Asian(up to 25.0)*** most consistent and rapid increase in AP incidence was noted in males aged 56–70 years with an alcoholic etiology(average 6%annual incidence growth).Conclusions:The incidence and annual trends of AP vary significantly among demographic and socioeconomic groups and this knowledge may be useful for the planning of healthcare resources and identification of at-risk populations.

关键词： Pancreatitis Alcoholic pancreatitis Incidence Seasonal variation