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The vaginal and fecal microbiomes are related to pregnancy status in beef heifers

Journal of Animal Science and Biotechnology 2020年第1期11卷 58-70页

作者： Feilong Deng Maryanna mcclure Rick Rorie Xiaofan Wang Jianmin chai Xiaoyuan Wei Songjia Lai Jiangchao Zhao Department of Animal Science Division of AgricultureUniversity of ArkansasFayettevilleARUSA Farm Animal Genetic Resources Exploration and Innovation Key Laboratory of Sichuan Province Sichuan Agricultural UniversityChengduChina Special Key Laboratory of Microbial Resources and Drug Development Research Center for Medicine and BiologyZunyi Medical UniversityZunyiChina.

Background:The greatest impact on profitability of a commercial beef operation is ***,in beef heifers,little is known about the vaginal and fecal microbiota with respect to their relationship with *** this end,we followed heifers through gestation to examine the dynamics of vaginal and fecal microbial composition throughout ***:Heifers were exposed to an estrus synchronization protocol,observed over a 12-day period,artificially inseminated 12 h to 18 h after observed estrus,and subsequently exposed to bulls for a 50-day breeding *** samples were taken at pre-breeding(n=72),during the first(n=72),and second trimester(n=72)for all individuals,and third trimester for individuals with confirmed pregnancies(n=56).Fecal samples were taken at prebreeding(n=32)and during the first trimester(n=32),including bred and open *** generation sequencing of the V4 region of the 16 S rRNA gene via the Illumina Mi Seq platform was applied to all *** indices and the number of observed bacterial features were the same in fecal ***,significant differences in vaginal microbiome diversity between gestation stages were *** differences in beta-diversity were detected in vaginal or fecal samples regarding pregnancy status,but such differences were seen with fecal microbiome over *** Forest was developed to identify predictors of pregnancy status in vaginal(e.g.,Histophilus,clostridiaceae,campylobacter)and fecal(e.g.,Bacteroidales,Dorea)***:Our study shows that bovine vaginal and fecal microbiome could be used as biomarkers of bovine *** experiments are needed to validate these biomarkers and to examine their roles in a female’s ability to establish pregnancy.

关键词： Beef cattle Pregnancy Random forest Reproduction Vaginal microbiome

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Regional trends and petrologic factors inhibit global interpretations of zircon trace element compositions

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Geoscience Frontiers 2024年第5期15卷 300-307页

作者： Nick M.W.Roberts christopher J.Spencer stephen Puetz c.Brenhin Keller Simon Tapster Geochronology and Tracers Facility British Geological SurveyNottingham NG125GGUK Department of Geological Sciences and Geological Engineering Queen’s UniversityKingstonOntarioCanada 475 Atkinson Dr Suite 704HonoluluHI 96814USA Department of Earth Sciences Dartmouth CollegeHanoverNew HamphireUSA

The trace element composition of zircon reveals information about the melt that they are derived from,as such,detrital zircon trace element compositions can be used to interrogate melt compositions,and thus the evolution of the continental crust in time and ***,we present a global database of detrital zircon compositions and use it to test whether average global trends for five common petrogenetic proxies truly represent secular changes in continental *** demonstrate that the secular trend is broadly comparable across continental regions for Ti-in-zircon temperatures,but for other trace element ratios interrogated,secular trends are highly variable between continental *** trace element ratios result from multiple petrologic variables,we argue that these petrogenetic proxies can be overinterpreted if projected to global geologic *** particular,we caution against the interpretation of crustal thickness from trace elements in zircon,and we argue that our results negate current hypotheses concerning secular changes in crustal thickness.

关键词： Detrital zircon Trace elements Secular change Eu anomaly crustal thickness

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Multi-scale drivers of soil resistance predict vulnerability of seasonally wet meadows to trampling by pack stock animals in the Sierra Nevada,USA

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Ecological Processes 2020年第1期9卷 364-377页

作者： Joy S.Baccei Mitchel P.Mcclaran Tim J.Kuhn stephen c.Hart Environmental Systems Graduate Group University of CaliforniaMercedCA 95343USA Uc Merced Vernal Pools and Grassland Reserve UC Merced Natural Reserve SystemMercedCA 95343USA School of Natural Resources and the Environment University of ArizonaTucsonAZ 85721USA Resources Management and Science Yosemite National ParkEl PortalCA 95318USA Department of Life&Environmental Sciences and Sierra Nevada Research Institute University of CaliforniaMercedCA 95343USA.

Background:Meadow ecosystems have important ecological functions and support socioeconomic services,yet are subject to multiple stressors that can lead to rapid *** the Sierra Nevada of the western USA,recreational pack stock(horses and mules)use in seasonally wet mountain meadows may lead to soil trampling and meadow degradation,especially when soil water content is high and vegetation is ***:In order to improve the ability to predict meadow vulnerability to soil disturbance from pack stock use,we measured soil resistance(SR),which is an index of vulnerability to trampling disturbance,at two spatial scales using a stratified-random sampling *** then compared SR to several soil and vegetation explanatory variables that were also measured at the two spatial scales:plant community type(local scale)and topographic gradient class(meadow scale).Results:We found that local-scale differences in drivers of SR were contingent on the meadow scale,which is important because multiple spatial scale evaluation of ecological metrics provides a broader understanding of the potential controls on ecological processes than assessments conducted at a single spatial *** also found two contrasting explanatory models for drivers of SR at the local scale:(1)soil gravimetric water content effects on soil disaggregation and(2)soil bulk density and root mass influence on soil *** resistance was insufficient to sustain pack stock use without incurring soil deformation in wet plant communities,even when plant cover was maximal during a major ***:Our study provides new information on seasonally wet meadow vulnerability to trampling by pack stock animals using multi-scale drivers of SR,including the contrasting roles of soil disaggregation,friction,and *** work aims to inform meadow management efforts in the Sierra Nevada and herbaceous ecosystems in similar regions that are subject to seasonal soil saturation and livestock u

关键词： Hydrogeomorphic classification Hydrologic regime Pack stock Plant communities Soil properties Soil strength

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characterization of isolated homogeneous hypersurface singularities in c^4

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Science china Mathematics 2006年第11期49卷 1576-1592页

作者： YAU stephen S T Department of Mathematics Statistics and computer Science University of Illinois at ChicagoChicagoIL 60607-7045USA

Let V be a hypersurface with an isolated singularity at the origin in cn+1. It is a natural question to ask when V is defined by weighted homogeneous polynomial or homogeneous polynomial up to biholomorphic change of coordinates. In 1971, a beautiful theorem of Saito gives a necessary and sufficient condition for V to be defined by a weighted homogeneous polynomial. For a two-dimensional isolated hypersurface singularity V, Xu and Yau found a coordinate free characterization for V to be defined by a homogeneous polynomial. Recently Lin and Yau gave necessary and sufficient conditions for a 3-dimensional isolated hypersurface singularity with geometric genus bigger than zero to be defined by a homogeneous polynomial. The purpose of this paper is to prove that Lin-Yau's theorem remains true for singularities with geometric genus equal to zero.

关键词： homogeneous polynomials, hypersurface singularity, weighted homogeneous polynomial, geometric genus.

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Suspension Splittings and Self-maps of Flag Manifolds

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Acta Mathematica Sinica,English Series 2019年第4期35卷 445-462页

作者： Shizuo KAJI stephen THERIAULT Institute of Mathematics for Industry Kyushu University Mathematical Sciences University of Southampton

If G is a compact connected Lie group and T is a maximal torus, we give a wedge decomposition of ΣG/T by identifying families of idempotents in cohomology. This is used to give new information on the self-maps of G/T.

关键词： Flag manifold self-map stable splitting

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Variability of the useful life of reservoirs in tropical locations:A case study from the Burdekin Falls Dam, Australia

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International Journal of Sediment Research 2018年第2期33卷 93-106页

作者： Michelle cooper stephen E.Lewis Thomas c.Stieglitz Scott G.Smithers college of Scilence and Engineering James Cook University centre for Tropical Water ε Aquatic Ecosystem Research TropWATER James Cook University

Large dam construction for irrigation, hydropower, water supply, and flood control in tropical to subtropical areas increased markedly after 1950. Many of the dams built during this period have filled with sediment and no longer perform to their original design specifications; in many cases, forecast dam life was greatly overestimated. This study investigates the useful life of Burdekin Falls Dam(BFD), northeastern Australia and compares the findings with other tropical reservoirs. Using two independent methods it is estimated that between 61 and 65 million m3 of sediment has been deposited in the reservoir over the 24 years of operation through 2011. This sediment volume equates to an average of0.15% of capacity lost per year since construction was completed. If current sediment loads/climate regimes persist, reservoir capacity will be reduced by 50% after 345 years. However, the useful life of the BFD reduces to just 276 years when drawdown data are considered; these data show reservoir use would be affected once 40% of storage was filled with sediment, with a 60% drawdown return period of 1 in 15 years. When compared to similar large tropical to sub-tropical reservoirs, the BFD has a slightly longer reservoir useful life than dams in India and a much longer half-life than for both similar-sized and larger dams in china, Brazil, and Iran. Properties of the BFD that promote a longer useful life include a lower trap efficiency, relatively low annual sediment load delivered to the reservoir, limited sediment deposition behind the dam wall(and uniform distribution of deposited sediment), and the export of highly turbid annual floodwaters before settling and deposition of any remaining sediment within the reservoir.

关键词： Reservoir half-life Lake Dalrymple Sediment trapping Trap efficiency Tropical reservoir Useful life

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Efficacy of infliximab in acute severe ulcerative colitis:A single-centre experience

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World Journal of Gastroenterology 2013年第7期19卷 1091-1097页

作者： stephen J Halpin P John Hamlin Daniel P Gree Lisa Warren Alexander c Ford Leeds Gastroenterology Institute St.James's University HospitalLeedsWest Yorkshire LS9 7TFUnited Kingdom Leeds Gastroenterology Institute St.James's University HospitalLeedsWest Yorkshire LS9 7TFUnited Kingdom r Leeds Institute of Molecular Medicine University of LeedsLeedsWest Yorkshire LS9 7TFUnited Kingdom

AIM:To suggest infliximab(IFX) is effective for acute severe ulcerative colitis,from real-life clinical ***:All patients receiving IFX for the treatment of acute severe ulcerative colitis in a single centre were *** were extracted from clinical records in order to assess response to IFX *** primary endpoint was colectomy-free survival,and secondary outcomes included glucocorticosteroid-free remission and safety,which was evaluated by recording deaths and adverse *** and clinical characteristics of those who underwent colectomy and those who were colectomy-free,both at discharge from their index admission,and during follow-up after an initial response to IFX were ***:Forty-four patients(16 females,mean age 36 years) received IFX between May 2006 and January 2012 for acute severe ulcerative *** median duration of follow-up post-first infusion was 396 d(interquartile range = 173-828 d).There were 21(47.7%) patients with 2 years of follow-up post-first infusion of ***,35(79.5%) responded to IFX,avoiding colectomy during their index admission,29(65.9%) were colectomyfree at last point of follow-up(median follow-up 396 d),and 25(56.8%) were in glucocorticosteroid-free remission at end of *** was one death from post-operative sepsis,20 d after a single IFX *** rates were generally lower among those "bridging" to *** 18 patients "bridged" to thiopurine therapy,17(94.4%) were colectomyfree,and 15(83.3%) were in glucocorticosteroid-free remission at study *** predictors of response were ***:IFX is effective for acute severe ulcerative colitis in real-life clinical ***-thirds of patients avoided colectomy,and more than 50% were in glucocorticosteroid-free remission.

关键词： Ulcerative colitis Severe Azathioprine Infliximab Remission

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Binding of cry δ-endotoxins to brush border membrane vesicles of Helicoverpa armigera and Helicoverpa punctigera （Lepidoptera： Noctuidae）

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Insect Science 2005年第4期12卷 231-240页

作者： cHUNYAN LIAO LIZ BROOKS stephen c. TROWELL RAYMOND J. AKHURST cSIRO Entomology Australian National University ACT Australia Division of Biochemistry and Molecular Biology Australian National University ACT Australia

The relatively low susceptibility ofHelicoverpa armigera to crylAc, its history of resistance to chemical insecticides and the seasonal decline in expression of crylAc in transgenic cotton necessitated the development of cotton expressing two insecticidal proteins to provide sustainable control of this multinational pest. To manage the resistance issue, it was essential that the second insecticidal protein have a significantly different mode of action to crylAc. A common feature of resistance to crylA proteins in several species as well as H. armigera has been a change in the binding site. A study of binding sites for some cry proteins in the brush border membrane vesicles （BBMV） ofH. armigera and Helicoverpa punctigera was undertaken. The binding affinity for crylAc was higher than for crylAb, matching their relative toxicities, and crylAc and crylAb were found to share at least one binding site in both I-1. armigera and I-1. punctigera. However cry2Aa did not compete with crylAc for binding and so could be used in transgenic cotton in combination with crylAc to control H. armigera and manage resistance. Variation in the susceptibilities of three different H. armigera strains to crylAc correlated with the parameter Bmax/Kcom.

关键词： Helicoverpa armigera Helicoverpa punctigera Bacillus thuringiensis δ-endotoxin brush border membrane vesicles ligand binding

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Sedimentary records of contaminant inputs in Frobisher Bay,Nunavut

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Environmental Science and Ecotechnology 2024年第2期18卷 28-42页

作者： Meaghan c.Bartley Tommy Tremblay Amila O.De Silva c.Michelle Kamula stephen ciastek Zou Zou A.Kuzyk centre for Earth Observation Science Clayton H.Riddell Faculty of EnvironmentEarth and ResourcesUniversity of ManitobaWinnipegManitobaR3T 2N2Canada Department of Environment and Geography Clayton H.Riddell Faculty of EnvironmentEarth and ResourcesUniversity of ManitobaWinnipegManitobaR3T 2N2Canada canada-Nunavut Geoscience Office IqaluitNunavutX0A 0H0Canada Environment and climate change canada BurlingtonOntarioL7S 1A1Canada Department of Earth Sciences Clayton H.Riddell Faculty of EnvironmentEarth and ResourcesUniversity of ManitobaWinnipegManitobaR3T 2N2Canada

contaminants,such as polychlorinated biphenyls(PcBs),polycyclic aromatic hydrocarbons(PAHs),heavy metals,and per and polyfluoroalkyl substances(PFASs),primarily reach the Arctic through long-range atmospheric and oceanic ***,local sources within the Arctic also contribute to the levels observed in the environment,including legacy sources and new sources that arise from activities associated with increasing commercial and industrial *** city of Iqaluit in Frobisher Bay,Nunavut(canada),has seen rapid population growth and associated development during recent decades yet remains a site of interest for ocean protection,where Inuit continue to harvest country *** the present study,seven dated marine sediment cores collected in Koojesse Inlet near Iqaluit,and from sites in inner and outer Frobisher Bay,respectively,were analyzed for total mercury(THg),major and trace elements,PAHs,PcBs,and *** sedimentary record in Koojesse Inlet shows a period of Aroclor 1260-like PcB input concurrent with military site presence in the 1950e60s,followed by decades of input of pyrogenic PAHs,averaging about ten times background ***-surface sediments in Koojesse Inlet also show evidence of transient local-source inputs of THg and PFASs,and recycling or continued slow release of PcBs from legacy land-based *** in PFAS congener composition clearly distinguish the local sources from long-range *** Koojesse Inlet but still in inner Frobisher Bay,9.2 km from Iqaluit,sediments showed evidence of both local source(PcB)and longrange *** outer Frobisher Bay,an up-core increase in THg and PFASs in sediments may be explained by ongoing inputs of these contaminants from long-range *** context for ocean protection and country food harvesting in this region of the Arctic clearly involves both local sources and long-range transport,with past human activities leaving a long legacy insofar as levels of persistent o

关键词： Arctic sediments Mercury Polycyclic aromatic hydrocarbons(PAHs) Polychlorinated biphenyls(PcBs) Per and polyfluoroalkyl substances(PFASs) Persistent organic pollutants(POPs)

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Occurrence, predication, and control of coal burst events in the U.S.

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International Journal of Mining Science and Technology 2016年第1期26卷 39-46页

作者： lannacchione Anthony T. Tadolini stephen c. civil Engineering University of Pittsburgh Pittsburgh PA 15260 USA Minova Americas Lakewood CO USA

coal burst represented a major hazard for some U.S. mining operations. This paper provides an historical review of the coal burst hazards,identifies the fundamental geological factors associated with these events,and discusses mechanisms that can be used to avoid their occurrences. coal burst are not common in most underground mines. Their occurrence almost always has such dramatic consequences to a mining operation that changes in practice are required. Fundamental factors influencing coal burst events include strong strata,abnormal strata caving,elevated stresses,critical size pillars and the lack of sufficiently sized barrier pillars during extraction. These factors interact to produce excessive stress,seismic shock and loss of confinement mechanisms. Over the 90 years of dealing with these hazards,many novel prevention controls have been developed including novel mine designs and extraction sequences,most of which are site specific in their application. Without an accurate assessment of the fundamental factors that influence coal burst and knowledge of their mechanisms of occurrence,control techniques may be misapplied and risk inadequately mitigated.

关键词： coal burstcoal bounceSeismicitycoal bump

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