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Seed value influences cache pilfering rates by desert rodents

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Integrative Zoology 2019年第1期14卷 75-86页

作者： Stephen B.VANDER WALL Lindsay A.DImITRI William S.LONGLAND Joseph D.m.white Department of Biology and Program in Ecology Evolution and Conservation BiologyUniversity of NevadaRenoUSA USDA Agricultural Research ServiceRenoNevadaUSA Department of Biological Sciences University of Cape TownCape TownRepublic of South Africa

Some rodents gather and store *** many seeds they gather and how they treat those seeds is largely determined by seed traits such as mass,nutrient content,hardness of the seed coat,presence of secondary compounds,and germination *** their consumption and dispersal of seeds,rodents act as agents of natural selection on seed traits,and those traits influence how rodents *** seeds that are scatter-hoarded by rodents are pilfered,or stolen,by other rodents,and seed traits also likely influence pilfering rates and seed fates of pilfered *** clarify coevolutionary relationships between rodents and the plants that they disperse,one needs to understand the role of seed traits in rodent foraging *** compared how the seeds of 4 species of plants that are dispersed by scatter-hoarding animals and that differ in value(singleleaf piñon pine,Pinus monophylla;desert peach,Prunus andersonii;antelope bitterbrush,Purshia tridentata;Utah juniper,Juniperus osteosperma)were pilfered and recached by *** hundred artificial caches of the 4 seed species(25 per species)were prepared,and removal by rodents was *** pilfered high-value seeds more rapidly than the other *** peach seeds,which contain toxic secondary compounds,were more frequently *** low value seeds like Utah juniper and antelope bitterbrush were pil-fered more slowly and were sometimes left at cache sites,and seeds of the latter species were transported shorter distances to new cache *** background density of seeds also appeared to influence the relative value of seeds.

关键词： desert rodents food storage granivory pilfering scatter-hoarding seed dispersal seed traits

Alignment between galaxies and large-scale structure

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Chinese Journal of Astronomy and Astrophysics 2009年第1期9卷 41-58页

作者： A. Faltenbacher Cheng Li Simon D. m. white Yi-Peng Jing Shu-De mao Jie Wang max-Planck-Institute for Astrophysics Karl-Schwarzschild-Str. 1 D-85741 Garching Germany mPA/SHAO Joint Center for Astrophysical Cosmology at Shanghai Astronomical Observatory Shanghai 200030 China Jodrell Bank Centre for Astrophysl＇cs Alan Turing Building The University of Manchester Manchester M13 9PL UK Department of Physics Institute of Computational Cosmology University of Durham Science Laboratories South Road Durham DH1 3LE UK

Based on the Sloan Digital Sky Survey DR6 （SDSS） and the ＇millennium Simulation （mS）, we investigate the alignment between galaxies and large-scale structure. For this purpose, we develop two new statistical tools, namely the alignment correlation function and the cos（20）-statistic. The former is a two-dimensional extension of the traditional two-point correlation function and the latter is related to the ellipticity correlation function used for cosmic shear measurements. Both are based on the cross correlation between a sample of galaxies with orientations and a reference sample which represents the large-scale structure. We apply the new statistics to the SDSS galaxy catalog. The alignment correlation function reveals an overabundance of reference galaxies along the major axes of red, luminous （L 〉～L＊） galaxies out to projected separations of 60 h-lmpc. The signal increases with central galaxy luminosity. No alignment signal is detected for blue galaxies. The cos（2θ）-statistic yields very similar results. Starting from a mS semi-analytic galaxy catalog, we assign an orientation to each red, luminous and central galaxy, based on that of the central region of the host halo （with size similar to that of the stellar galaxy）. As an alternative, we use the orientation of the host halo itself. We find a mean projected misalignment between a halo and its central region of -25°. The misalignment decreases slightly with increasing luminosity of the central galaxy. Using the orientations and luminosities of the semi-analytic galaxies, we repeat our alignment analysis on mock surveys of the mS. Agreement with the SDSS results is good if the central orientations are used. Predictions using the halo orientations as proxies for cen- tral galaxy orientations overestimate the observed alignment by more than a factor of 2. Finally, the large volume of the mS allows us to generate a two-dimensional map of the alignment correlation function, which shows the reference galaxy distrib

关键词： dark matter halos clustering-galaxies large-scale structure of Universe- cosmology theory -dark matter

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DARKENERGY

Chinese Physics C 2016年第10期40卷 402-410页

作者： D. H. Weinberg m. white m. J. mortonson OSU UCB LBL

27.1. Repulsive Gravity and Cosmic Acceleration In the first modern cosmological model, Einstein [1] modified his field equation of General Relativity （GR）, introducing a ＂cosmological term＂ that enabled a solution with time-independent, spatially homogeneous matter density pm and constant positive space curvature. Although Einstein did not frame it this way, one can view the ＂cosmological constant＂ A as representing a constant energy density of the vacuum [2], whose repulsive gravitational effect balances the attractive gravity of matter and thereby allows a static solution. After the development of dynamic cosmological models [3,4] and the discovery of cosmic expansion [5], the cosmological term appeared unnecessary, and Einstein and de Sitter [6] advocated adopting an expanding, homogeneous and isotropic, spatially flat, matter-dominated universe as the default cosmology until observations dictated otherwise.

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Endo-anesthesia:a primer

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Gastroenterology Report 2022年第1期10卷 207-216页

作者： Fateh Bazerbachi Rodger m.white Nauzer Forbes Basavana Goudra Barham K.Abu Dayyeh Vinay Chandrasekhara BobbieJean Sweitzer CentraCare Interventional Endoscopy ProgramSt.Cloud HospitalSt CloudMNUSA Department of Anesthesia Massachusetts General HospitalBostonMAUSA Department of medicine Division of Gastroenterology and HepatologyUniversity of CalgaryCalgaryAlbertaCanada Department of Anesthesiology and Critical Care medicine Hospital of the University of PennsylvaniaPhiladelphiaPAUSA Division of Gastroenterology and Hepatology Mayo ClinicRochesterMNUSA Systems Director University of VirginiaPreoperative MedicineInovaHealthFalls ChurchVAUSA

Gastrointestinal(GI)endoscopy has witnessed a Cambrian explosion of techniques,indications,and expanding target *** endoscopy encompasses traditional domains that include preventive measures,palliation,as alternative therapies in patients with prohibitive risks of more invasive procedures,and indicated primary ***,it has expanded to include therapeutic and diagnostic interventional endosonography,luminal endoscopic resection,third space endotherapy,endohepatology,and *** lines between surgery and endoscopy are blurred on many occasions within this ***,patients with high degrees of co-morbidity and complex physiology require more nuanced peri-endoscopic *** rising demand for endoscopy services has resulted in the development of endoscopy referral centers that offer these invasive procedures as directly booked referrals for regional and rural *** further necessitates specialized programs to ensure appropriate evaluation,risk stratification,and optimization for safe sedation and general anesthesia if *** landscape is conducive to the organic evolution of endo-anesthesia to meet the needs of these focused and evolving *** this primer,we delineate important aspects of endo-anesthesia care and provide relevant clinical and logistical considerations pertaining to the breadth of procedures.

关键词： endoscopic procedures endoscopy anesthesia

Fluid mechanics 5th ed.

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分水岭区深部白质的病理特征:mELAS中枢神经系统受累的一种新模式

丛书名： mcGraw-Hill series in mechanical engineering

2003年

作者： Frank m white

来源：畅想之星图书光盘版（南... 评论

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世界核心医学期刊文摘（神经病学分册） 2005年第11期1卷 11-12页

作者： Apostolova L.G. white m. moore S.A. Davis P.H. 夏峰 Dr. UCLA Alzheimer’s Disease Research Center RNRC 2-238 710 Westwood Blvd Los Angeles CA 90095 United States

Background: myopathy, encephalopathy, lactic acidosis, and stroke-like episodes (mELAS) syndrome typically manifests in adults younger than 40 years with encephalopathy, strokelike episodes, and lactic acidosis. magnetic resonance imaging (mRI) abnormalities typically involve the cortical gray and the adjacent subcortical white matter. Objective: To describe a 58-year-old woman diagnosed with mELAS who was initially seen with acute myopathy, cardiac ischemia, psychosis, and mRI changes in a watershed distribution. Results: Initial mRI of the brain showed the characteristic parieto-occipital gray matter lesions involving the adjacent white matter. Follow-up mRI revealed striking deep white matter involvement in a watershed distribution. A cerebral angiogram and thorough hypercoagulable workup results were normal. Electromyography showed acute denervation and myopathy. A muscle biopsy specimen revealed ragged red and cytochrome-c oxidase-negative fibers. mitochondrial DNA analysis revealed an A3243G mutation. Conclusions: myopathy, encephalopathy, lactic acidosis, and stroke-like episodes should be considered in older patients with myopathy, cardiomyopathy, encephalopathy, and unaccountable mRI findings. Watershed pathologic features are a rare pattern of cerebral involvement in mELAS.

关键词： mELAS 分水岭区中枢神经系统卒中发作脑血管造影肌肉活检大脑灰质肌病脑病乳酸酸中毒

Structure of the Ligated Ag60 Nanoparticle [{Cl@Ag12}@Ag48（dppm）12]（where dppm=bis（diphenylphosphino）methane）

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Chinese Journal of Chemical Physics 2019年第2期32卷 182-186,I0002页

作者： Athanasios Zavras Antonija mravak margarita Buzancic Jonathan m.white Vlasta Bonacic-Koutecky Richard A.J.O’Hair School of Chemistry and Bio21 molecular Science and Biotechnology Institute University of Mel- bourne 30 Flemington Rd Parkville Victoria 3010 Australia Center of Excellence for Science and Technology-Integration of mediterranean Region (STIm) at Interdisciplinary Center for Advanced Sciences and Technology (ICAST) University of Split Poljicka cesta 35 Split 21000 Croatia Chemistry Department Humboldt University of Berlin Brook-Taylor-Strasse 2 Berlin 12489 Germany

A novel bisphosphine ligated Ag60 nanocluster,[{Cl@Ag12}@Ag48(dppm)12], has been dis-covered and characterized by X-ray crystallography. It consists of a central chloride located inside an icosahedral silver core layer, which is further encased by a second shell of 48 silver atoms/ions, which are capped with 12 bis(diphenylphosphino)methane (dppm) ligands. Due to lack of sufficient material the cluster could not be further characterized by other methods. DFT calculations were carried out on the cation [{Cl@Ag12}@Ag48(dppm)12]+ to determine if it corresponds to a superatom with a core count of n=58. The DFT optimized structure is in agreement with X-ray ndings, but the low value of the HOmO-LUmO gap does not support superatom stability.

关键词： Nanoparticle DFT calculations X-ray crystallography

Endocrine Indices of PCOS in Women with Polycystic Ovaries but without Diagnostic Features of PCOS: A Study of an Infertility Clinic Population

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Open Journal of Obstetrics and Gynecology 2020年第2期10卷 275-283页

作者： Eleni Kousta Davinia m. white Desmond G. Johnston Stephen Franks S. Arvanitaki 6 Corfu Greece Reproductive medicine Clinic Ground Floor Southwark Wing Guys Hospital Great Maze Pond London UK Diabetes Endocrinology and metabolic medicine Faculty of Medicine Imperial College London St. Mary’s Campus Room G1 Norfolk Place London UK Institute of Reproductive and Developmental Biology Imperial College London Hammersmith Hospital London UK

Background: The presence of polycystic ovarian morphology (PCO) without the other characteristics of the polycystic ovarian syndrome (PCOS) is insufficient for the diagnosis of PCOS and there is little justification for follow up in endocrine clinics for women with PCO morphology alone. A few studies have been reported regarding the endocrine features of asymptomatic women with PCO with conflicting data about endocrine profiling. The aim of this study was to assess whether women with PCO, but who have no symptoms of PCOS differ, endocrinologically, from women with normal ovaries.?methods: We analysed the results of ultrasound and endocrine investigations in 576 consecutive women who attended the infertility clinic between 1993 and 1995 at the Reproductive medicine Unit of St mary’s Hospital, Imperial College Healthcare NHS Trust, London, UK. Results: Three hundred and twenty eight women had PCO and 248 had normal ovaries. Among the 328 women with PCO, 169 (51.5%) had PCOS according to Rotterdam criteria. The remaining women with PCO had no symptoms of the syndrome (n = 159);they had a history of regular menses, had proven ovulatory cycles and had neither clinical nor biochemical evidence of hyperandrogenism. However, these women had higher timed LH [median (IQR) 5.3 (4.2) IU/l vs 4.8 (3.4) IU/l, respectively;p = 0.044] and testosterone [2.0 (0.8) nmol/l vs 1.8 (0.8), respectively;p = 0.009] compared with women with normal ovaries (although by definition within the normal range). There was no difference in BmI or FSH between the two groups. Among the 169 women with PCOS, 45.0% (n = 76) were anovulatory without hyperandrogenism, 34.3% (n = 58) fulfilled the NIH criteria and 20.7% (n = 35) were ovulatory with hyperandrogenism. The proportion of hyperandrogenism among anovulatory women with PCO is 43.3% (58 out of 134).?Conclusions: Women with PCO, but no symptoms of the syndrome, differ endocrinologically compared with women with normal ovaries: they had higher timed L

关键词： Polycystic Ovary Syndrome Polycystic Ovarian morphology Ultrasound Scan Infertility Clinic

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仔猪腹泻的防治

国外畜牧科技 1989年第2期16卷 53-54页

作者： m.white 于滨

仔猪腹泻是仔猪最为常见的疾病。有时是多数圈舍的猪一时性发生,有时是少数圈舍的猪经常发生。但腹泻只是疾病的一个症状。健康猪肠道中的微生物和其外界环境中的微生物处于平衡状态。破坏这一平衡的任何因素都可导致肠道的功能紊乱,并... 详细信息

仔猪腹泻是仔猪最为常见的疾病。有时是多数圈舍的猪一时性发生,有时是少数圈舍的猪经常发生。但腹泻只是疾病的一个症状。健康猪肠道中的微生物和其外界环境中的微生物处于平衡状态。破坏这一平衡的任何因素都可导致肠道的功能紊乱,并出现腹泻。因此,可以断定腹泻是多方面因素影响的结果。其中包括感染、饲料、环境卫生和管理。要想有效地控制本病,就必须对引起本病的所有病因进行鉴定,并设计一个合适的防治方案。

关键词：仔猪腹泻防治猪