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Intraspecific temporal resource partitioning at white-tailed deer feeding sites

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Current Zoology 2019年第2期65卷 139-146页

作者： David B. STONE j.mes A. MARTIN Bradley S. COHEN thomas j. PREBYL Charlie KILLMASTER Karl V. MILLER Warnell School of Forestry and Natural Resources University of Georgia Athens GA USA Savannah River Ecology Lab University of Georgia Aiken SC USA Department of Biology Tennessee Technological University Cookeville TN USA Georgia Department of Natural Resources Atlanta GA USA

Individuals may reduce competition by temporally partitioning their use of a shared resource. Behavioral differences between sexes in ungulates may encourage segregation as individuals attempt to avoid antagonistic interactions. However, dominant sex and age groups may reduce subordinates' access to food resources, regardless of the subordinate's sex. We hypothesized that white-tailed deer Odocoileus Virginian us temporally segregated at supplemental feedi ng sites based on social rank (subordinate: yearling males and adult females;dominant: adult males) and that segregation was affected by phase of the breeding season and diel cycle. If deer temporally segregate according to social rank, we predicted that the resulting activity patterns would manifest in one social class being relatively more susceptible to hunter-induced mortality. We used a multistate modeling approach to quantify temporal segregation and calculated the probability that a feeding site was in a particular state during diurnal and nocturnal hours for each of the 3 phases of the breeding season. We determined that transition probabilities differed by season and diel cycle and dominant and subordinate social classes clearly avoided each other, with <1% co-occurrenee at feedi ng sites. During the pre-breedi ng seas on, the probability of a subordi nate being present during diurnal hours was *** more likely than a dominant being present, but did not differ during nocturnal hours. There was no difference for dominants and subordinates during diurnal or no cturnal hours during the breedi ng season .In the post-breedi ng season, subordi nates were 1.7x more likely to occur at the feeding site than a dominant during diurnal hours but they did not differ during nocturnal hours. Our results indicate that dominance status influences temporal segregation at feeding sites and is affected by the phase of the breeding season. Therefore, the resulti ng activity patterns may in crease subordi nates' risk to human

关键词： competition multistate modeling predation risk supplemental feeding sites intraspecific temporal resource partitioning white-tailed deer

High Oxygen Nanocomposite Barrier Films Based on Xylan and Nanocrystalline Cellulose

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Nano-Micro Letters 2010年第4期2卷 235-241页

作者： Amit Saxena thomas j.Elder j.ffrey Kenvin Arthur j.Ragauskas School of Chemistry and Biochemistry Georgia Institute of Technology USDA-Forest Service Southern Research Station Micromeritics Instrument Corporation

The goal of this work is to produce nanocomposite film with low oxygen permeability by casting an aqueous solution containing xylan,sorbitol and nanocrystalline *** morphology of the resulting nanocomposite films was examined by scanning electron microscopy and atomic force microscopy which showed that control films containing xylan and sorbitol had a more open structure as compared to xylan-sorbitol films containing sulfonated nanocrystalline *** average pore diameter,bulk density,porosity and tortuosity factor measurements of control xylan films and nanocomposite xylan films were examined by mercury intrusion porosimetry *** films reinforced with nanocrystalline cellulose were denser and exhibited higher tortuosity factor than the control xylan *** xylan films had average pore diameter,bulk density,porosity and tortuosity factor of 0.1730 μm,0.6165 g/ml,53.0161% and 1.258,respectively as compared to xylan films reinforced with 50% nanocrystalline cellulose with average pore diameter of 0.0581 μm,bulk density of 1.1513 g/ml,porosity of 22.8906% and tortuosity factor of *** transmission rate tests demonstrated that films prepared with xylan,sorbitol and 5%,10%,25% and 50% sulfonated nanocrystalline cellulose exhibited a significantly reduced oxygen permeability of 1.1387,1.0933,0.8986 and 0.1799 cm^3×μm/m^2×d×k Pa respectively with respect to films prepared solely from xylan and sorbitol with a oxygen permeability of 189.1665 cm^3×μm/m^2×d×k *** properties suggested these nanocomposite films have promising barrier properties.

关键词： Nanocomposites Xylan Nanocrystalline cellulose Oxygen barrier

Isotretinoin for the treatment of nonobstructive azoospermia: a pilot study

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Asian j.urnal of Andrology 2021年第5期23卷 537-540页

作者： j.hn K Amory Charles H Muller thomas j.Walsh Department of Medicine University of WashingtonSeattleWA 98195USA Department of Urology University of WashingtonSeattleWA 98195USA

The treatment of men with infertility from azoospermia is *** some men with severe oligozoospermia improve sperm output during treatment with isotretinoin,we treated nine men with azoospermia with isotretinoin to determine if azoospermic men would also respond to isotretinoin *** of these men who had a previous negative testicular sperm extraction(TESE)was found to have an area of sperm production on a postisotretinoin testicular *** man achieved a pregnancy and a live birth of a healthy,term daughter after in vitro fertilization coupled with intracytoplasmic sperm inj.ction(IVF/ICSI).A second subj.ct had a positive TESE after treatment as *** study of isotretinoin therapy in men with azoospermia undergoing testicular sperm harvesting procedures is warranted.

关键词： treatment inj.ction pregnancy

Testing semiochemicals from aphid, plant and conspecific： attraction of Harmonia axyridis

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Insect Science 2012年第3期19卷 372-382页

作者： Pascal D. Leroy thomas Schillings j.lien Farmakidis Stephanie Heuskin Georges Lognay Francois j. Verheggen Yves Brostaux Eric Haubruge Frederic Francis Departments of Functional and Evolutionary Entomology Departments of Analytical Chemistry Departments of Applied Statistics Computer Science and Mathematics University of Liege Gembloux Agro-Bio Tech Gembloux Belgium

Harmonia axyridis Pallas （Coleoptera： Coccinellidae） is an invasive specie affecting the dynamics and composition of several guilds. Nowadays, no biological control method is available to reduce the populations of this harmful coccinellid. Attractants and semiochemicals seem to be the best alternative but only few studies have tested the impact of semiochemicals on this Asian lady beetle. In this work, through wind- tunnel experiments, semiochemicals from aphids （Z,E-nepetalactone, [E]-β-farnesene, a-pinene and β-pinene）, from coccinellids （[-]-β-earyophyllene） and from the nettle Urtica dioica L. were evaluated as potential attractants. The nettle volatile compounds （[Z]-3- hexenol and [E]-2-hexenal） were extracted using a Clevenger Apparatus and identified by headspace gas chromatography-mass spectroscopy. In the wind-tunnel experiments, the main components of the aphid alarm pheromone as well as a component of the aphid sexual pheromone strongly attracted both sexes of the Asian lady beetle while （-）-β- caryophyllene only attracted few individuals and had no impact on the males. The nettle extract as well as the （Z）-3-hexenol oriented both males and females to the odor source. The （E）-2-hexenal was shown to have no effect on females even if this green leaf volatile attracted males. Because Z,E-nepetalactone was identified as the most efficient attractant in the wind-tunnel experiments, this volatile was also tested in a potato field where H. axyridis has been showed to respond to this semiochemical. This study highlighted that Z,E-nepetalactone orientated the Asian lady beetle H. axyridis under natural condi- tions, indicating that this volatile compound could certainly help for an efficient biological control approach against this invasive specie.

关键词： aphids attractant Harmonia axyridis plant semiochemicals wind-tunnel

The impact of vitamin D deficiency on neurogenesis in the adult brain

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Neural Regeneration Research 2017年第3期12卷 393-394页

作者： Natalie j.Groves thomas H.j.Burne Queensland Brain Institute The University of QueenslandSt.LuciaAustralia Queensland Centre for Mental Health Research The Park Centrefor Mental HealthWacolAustralia

There is increasing evidence from epidemiological studies indicating that vitamin D deficiency during adulthood is associated with adverse brain outcomes in humans（Ginde et al.,2009）and rodents（Groves et al.,2014）... 详细信息

关键词： The impact of vitamin D deficiency on neurogenesis in the adult brain GAD

Pink bollworm moth （Lepidoptera： Gelechiidae） catches in the Imperial Valley, California from 1989 to 2003

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Insect Science 2006年第6期13卷 469-475页

作者： CHANG-CHI CHU ERIC T. NATWICK RAUL LEON LOPEZ j.LENER. DESSERT thomas j. HENNEBERRY USDA-ARS U.S. Arid Land Regearch Center Maricopa AZ University of California Cooperative Research and Extension Holtville California USA Instituto Nacionel de Investigaciones Forestales Agricolasy Pecuxrias Mexicali B.C. Mexico Imperial County Agricultural Commissioner s Office EI Centrb California USA

We examined the patterns of male pink bollworm （PBW）, Pectinophora gossypiella （Saunders）, moth catches in gossyplure-baited traps over a 15-year period from 1989 to 2003 in the Imperial Valley, California, USA. Monitoring was conducted during periods when different pink bollworm areawide control strategies were being used. Numbers of male pink bollworm moths caught in gossyplure-baited traps progressively decreased each year from 1990 to 1994 during short-season cotton production. High numbers of male moths caught in traps from 1995 to 1997 may have been related to moth migrations from the large cotton acreages grown in the Mexicali Valley bordering the Imperial Valley. Transgenic Bollgard （Bt） cotton was planted in 3% of the cotton area in 1996 and thereafter in 80%- 94% of the cotton area from 1997 to 2003. Pink bollworm moth trap catches were significantly lower from 1998 to 2003 than catches in 1995 to 1997, except for 1999. The trapping results suggested that Bt cotton had significant input on reduction of pink bollworm populations, confirming results of other investigators and providing additional documentation on the benefits of the Bt cotton culture.

关键词： Bt cotton diapause larvae gossyplure migration Pectinophora gossypiella short-season cotton

Multiscale Domain Decomposition Methods for Elliptic Problems with High Aspect Ratios

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Acta Mathematicae Applicatae Sinica 2002年第1期18卷 63-76页

作者： j.rgAarnes thomas Y.Hou Department of Mathematics University of BergenJohs.Brunsgt.125008 BergenNorwayApplied Mathematics217-50CaltechPasadenaCA 91125

In this paper we study some nonoverlapping domain decomposition methods for solving a class of elliptic problems arising from composite materials and flows in porous media which contain many spatial scales. Our preconditioner differs from traditional domain decomposition preconditioners by using a coarse solver which is adaptive to small scale heterogeneous features. While the convergence rate of traditional domain decomposition algorithms using coarse solvers based on linear or polynomial interpolations may deteriorate in the presence of rapid small scale oscillations or high aspect ratios, our preconditioner is applicable to multiple-scale problems without restrictive assumptions and seems to have a convergence rate nearly independent of the aspect ratio within the substructures. A rigorous convergence analysis based on the Schwarz framework is carried out, and we demonstrate the efficiency and robustness of the proposed preconditioner through numerical experiments which include problems with multiple-scale coefficients, as well problems with continuous scales.

关键词： Multiscale elliptic problems Domain decomposition Schwarz methods Porous media

Recent Increased Warming of the Alaskan Marine Arctic Due to Midlatitude Linkages

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Advances in Atmospheric Sciences 2018年第1期35卷 75-84页

作者： j.mes E.OVERLAND Muyin WANG thomas j.BALLINGER NOAA/Pacific Marine Environmental Laboratory Seattle WA 98115USA j.int Institute for the Study of Atmosphere and Oceans University of Washington Seattle WA 98115USA Department of Geography Texas State UniversitySan Marcos TX 78666USA

Alaskan Arctic waters have participated in hemispheric-wide Arctic warming over the last two decades at over two times the rate of global warming. During 2008–13, this relative warming occurred only north of the Bering Strait and the atmospheric Arctic front that forms a north–south thermal barrier. This front separates the southeastern Bering Sea temperatures from Arctic air masses. Model proj.ctions show that future temperatures in the Chukchi and Beaufort seas continue to warm at a rate greater than the global rate, reaching a change of +4℃ by 2040 relative to the 1981–2010 mean. Offshore at 74°N, climate models proj.ct the open water duration season to increase from a current average of three months to five months by 2040. These rates are occasionally enhanced by midlatitude connections. Beginning in August 2014, additional Arctic warming was initiated due to increased SST anomalies in the North Pacific and associated shifts to southerly winds over Alaska, especially in winter 2015–16. While global warming and equatorial teleconnections are implicated in North Pacific SSTs, the ending of the 2014–16 North Pacific warm event demonstrates the importance of internal, chaotic atmospheric natural variability on weather conditions in any given year. Impacts from global warming on Alaskan Arctic temperature increases and sea-ice and snow loss, with occasional North Pacific support, are proj.cted to continue to propagate through the marine ecosystem in the foreseeable future. The ecological and societal consequences of such changes show a radical departure from the current Arctic environment.

关键词： Alaska North Pacific Arctic warm advection polar vortex

Heat and Mass Transfer Investigation of Hydrocarbon Droplet Evaporation under Rotatory Movement

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Chinese Physics Letters 2005年第11期22卷 2933-2935页

作者： j. Dgheim B. Zeghmati Groupe de Mécanique Acoustique et Instrumentation Centre d'Etudes Fondamentales UPRES EA 2986 Université de Perpignan 52 Avenue de Villeneuve 66860 Perpignan France

The steady-state boundary layer equations of a rotatory movement around hydrocarbon droplets saturated of pure fuel are numerically solved. The transfer equations are schemed by using an implicit finite difference method. The system of algebraic equations is solved by using the thomas algorithm. The model is compared to the Kreith one and a good agreement is observed between both models. The dimensionless physical parameters of the evaporation phenomena of droplet in rotation are calculated and presented under the effect of the convection.

关键词： Heat and Mass Transfer Investigation of Hydrocarbon Droplet Evaporation under Rotatory Movement