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Methane Emissions from Grazing Holstein-Friesian Heifers at Different Ages Estimated Using the Sulfur Hexafluoride Tracer Technique

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Engineering 2017年第5期3卷 753-759页

作者： steven j. Morrisonn j.dith McBride Alan W. Gordon Alastair R. G. Wylie Tianhai Yan Agri-Food and Biosciences Institute Hillsborough County Down BT26 6DR UK Agri-Food and Biosciences Institute Belfast BT9 5PX UK

Although the effect of animal and diet factors on enteric methane （CH4） emissions from confined cattle has been extensively examined, less data is available regarding CH4 emissions from grazing young cattle. A study was undertaken to evaluate the effect of the physiological state of Holstein-Friesian heifers on their enteric CH4 emissions while grazing a perennial ryegrass sward. Two experiments were conducted： Experiment 1 ran from May 2011 for 11 weeks and Experiment 2 ran from August 2011 for 10 weeks. In each experiment, Holstein-Friesian heifers were divided into three treatment groups （12 animals/group） consisting of calves, yearling heifers, and in-calf heifers （average ages： 8.5, 14.5, and 20.5 months, respectively）. Methane emissions were estimated for each animal in the final week of each experiment using the sulfur hexafluoride tracer technique. Dry matter （DM） intake was estimated using the calculated metabolizable energy （ME） requirement divided by the ME concentration in the grazed grass. As expected, live weight increased with increasing animal age （P 〈 0.001）; however, there was no difference in live weight gain among the three groups in Experiment 1, although in Experiment 2, this variable decreased with increasing animal age （P 〈 0.001 ）. In Experiment 1, yearling heifers had the highest CH4 emissions （g·d^-1） and in-calf heifers produced more than calves （P 〈 0.001 ）. When expressed as CH4 emissions per unit of live weight, DM intake, and gross energy （GE） intake, yearling heifers had higher emission rates than calves and in-calf heifers （P 〈 0.001）. However, the effects on CH4 emissions were different in Experiment 2, in which CH, emissions （g·d^-1） increased linearly with increasing animal age （P 〈 0.001）, although the difference between yearling and in-calf heifers was not significant. The CH4/live weight ratio was lower in in-calf heifers than in the other two groups （P 〈 0.001 ）, while CH4 energy output as a proportion of GE intake was lower

关键词： Methane emission Grazing dairy heifer Prediction Sulfur hexafluoride tracer technique

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Resolving impact volatilization and condensation from target rock mixing and hydrothermal overprinting within the Chicxulub impact structure

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Geoscience Frontiers 2022年第5期13卷 16-31页

作者： Thomas Déhais Stepan M.Chernonozhkin Pim Kaskes Sietze j.de Graaff Vinciane Debaille Frank Vanhaecke Philippe Claeys steven Goderis Analytical Environmental and Geo-ChemistryVrije Universiteit BrusselBrusselsBelgium Laboratoire G-Time UniversitécLibre de BruxellesBrusselsBelgium Department of Chemistry Atomic&Mass SpectrometryGhent UniversityGhentBelgium

This work presents isotopic data for the non-traditional isotope systems Fe,Cu,and Zn on a set of Chicxulub impactites and target lithologies with the aim of better documenting the dynamic processes taking place during hypervelocity impact events,as well as those affecting impact structures during the post-impact *** focus lies on material from the recent IODP-ICDP Expedition 364 Hole M0077A drill core obtained from the offshore Chicxulub peak *** ej.cta blanket samples from the UNAM 5 and 7 cores were used to compare the crater lithologies with those outside of the impact *** datasets of bulk Fe,Cu,and Zn isotope ratios are coupled with petrographic observations and bulk maj.r and trace element compositions to disentangle equilibrium isotope fractionation effects from kinetic *** observed Fe and Cu isotopic signatures,with δ^(56/54)Fe ranging from0.95‰to 0.58‰and δ^(65/63)Cu from0.73‰to 0.14‰,mostly reflect felsic,mafic,and carbonate target lithology mixing and secondary sulfide mineral formation,the latter associated to the extensive and long-lived(>105 years)hydrothermal system within Chicxulub *** the other hand,the stable Zn isotope ratios provide evidence for volatility-governed isotopic *** heavier Zn isotopic compositions observed for the uppermost part of the impactite sequence and a metamorphic clast(δ^(66/64)Zn of up to 0.80‰and 0.87‰,respectively)relative to most basement lithologies and impact melt rock units indicate partial vaporization of Zn,comparable to what has been observed for Cretaceous-Paleogene boundary layer sediments around the world,as well as for tektites from various strewn *** contrast to previous work,our data indicate that an isotopically light Zn reservoir(δ^(66/64)Zn down to0.49‰),of which the existence has previously been suggested based on mass balance considerations,may reside within the upper impact melt rock(UIM)*** observation is restricted to a few UIM sampl

关键词： Chicxulub impact structure Non-traditional stable isotopes Impact volatilization Impact condensation Hydrothermal alteration Target lithology mixing

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What is the purpose of launching the World j.urnal of Otorhinolaryngology？

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World j.urnal of Otorhinolaryngology 2011年第1期1卷 1-3页

作者： steven j.Wang Department of Otolaryngology-Head and Neck Surgery University of California San Francisco CA 94115 United StatesAuthor contributions: Wang SJ solely contributed to this paper.Correspondence to: Steven J Wang MD FACS Associate Professor Department of Otolaryngology-Head and Neck Sur-gery University of California 2233 Post St PO Box 1225 San Francisco CA 94115 United States. swang@ohns.ucsf.edu

We are pleased to announce the launching of the World j.urnal of Otorhinolaryngology （Wj.） as a new mem-ber of the World Series j.urnal family. The Wj. is a peer-reviewed open-access j.urnal dedicated to pub-lishing original research articles, review articles, clinical studies, and case reports in all areas of otorhinolaryn-gology. Please consider submitting your research fnd-ings in otorhinolaryngology to the Wj..

关键词： Otorhinolaryngology Biomedical sciences Peer-reviewed Open-access j.urnal

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miR398b negatively regulates cotton immune responses to Verticillium dahliae via multiple targets

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The Crop j.urnal 2022年第4期10卷 1026-1036页

作者： Yuhuan Miao Kun Chen j.nwu Deng Lin Zhang Weiran Wang j.e Kong steven j.Klosterman Xianlong Zhang Alifu Aierxi Longfu Zhu National Key Laboratory of Crop Genetic Improvement Huazhong Agricultural UniversityWuhan 430070HubeiChina Hubei University of Chinese Medicine Wuhan 430065HubeiChina Oil Crops Research Institute Chinese Academy of Agricultural SciencesWuhan 430062HubeiChina Institute of Economic Crops Xinjiang Academy of Agricultural SciencesUrumchi 842000XinjiangChina United States Department of Agriculture Agricultural Research ServiceSalinasCA 93905USA

MicroRNAs(miRNAs)play essential roles in plant defense responses,although such roles have not been identified in cotton in response to the plant pathogenic fungus Verticillium *** this study,the functions of miR398b and its target genes in *** interaction were *** transcript levels of miR398b were down-regulated by *** infection and miR398b overexpression in cotton made the plants more susceptible to *** results suggest that miR398b negatively regulates cotton resistance to *** may occur by miR398b repression of some CC-NBS-LRR genes via translational inhibition,interfering with defense responses and leading to cotton susceptibility to ***,miR398b may guide the cleavage of the mRNAs of GhCSD1,GhCSD2 and GhCCS,each of which functions in reactive oxygen species(ROS)regulation and homeostasis,thereby causing excessive ROS accumulation in miR398b-overexpressing plants in response to *** *** study suggests conserved and novel roles of miR398b in the cotton–*** *** discoveries may be coupled with new strategies in cotton breeding programs to improve resistance to ***.

关键词： Cotton miR398b NBS-LRR ROS homeostasis Verticillium dahliae

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基因与命运

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作者： (加)斯蒂芬·j. 海涅(steven j. Heine)

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Effect of Ambient UV-B on Stomatal Density, Conductance and Isotope Discrimination in Four Field Grown Soybean [<i>Glycine max</i>(L.) Merr.] Isolines

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American j.urnal of Plant Sciences 2013年第12期4卷 100-108页

作者： Dennis C. Gitz III steven j. Britz j.seph H. Sullivan Department of PLSA College of Agriculture and Natural Resources University of Maryland College Park USA USDA-ARS# Cropping Systems Research Laboratory Lubbock USA USDA-ARS Food Components and Health Laboratory Beltsville USA

An experiment was designed to test whether ambient levels of UV-B radiation affect stomatal development, decrease stomatal density, and lead to increased water-use efficiency (WUE). Soybean [Glycine max (L.) Merr.] isolines with different stomatal distribution and flavonol expression patterns were field grown under shelters that either transmitted or blocked solar UV-B. All isolines exposed to solar UV-B accumulated higher concentrations of UV-screening phenolic pigments but other responses were isoline dependent. Solar UV-B decreased stomatal density and conductance in isolines expressing a unique branched kaempferol triglycoside. Decreased stomatal density was associated with increased season-long WUE and decreased internal CO2 concentration of leaf (estimated by δ13C discrimination). We concluded that photomorphogenic responses to UV-B affected stomatal density and WUE in field grown soybean;but that the magnitude and direction of these response were associated with isogenic pleiotropic differences in stomatal distribution and pigment expression. UV-B radiation had no effect on biomass accumulation or yield in a cultivar expressing only trace levels of kaempferol suggesting that flavonol expression is not prerequisite to UV-B tolerance.

关键词： Soybean UV-B Drought Stress Water Use Efficiency Isotope Discrimination Photomorphogenesis

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The US ESRD program-can we get the genie back in the bottle?

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中国血液净化 2014年第12期13卷 851-853页

作者： steven j.Rosansky Dorn Research Institute William Jennings Bryan Dorn VA Medical Center

1972年美国社会保险立法修订案决定为终末期肾病(ESRD)治疗提供基金,并开始对其发病和患病情况进行监测。1988年美国建立了肾脏病数据系统(USRDS),使监测数据更为准确。美国大学的Rosansky教授着眼于ESRD开始透析时机,对美国ESRD管理系... 详细信息

1972年美国社会保险立法修订案决定为终末期肾病(ESRD)治疗提供基金,并开始对其发病和患病情况进行监测。1988年美国建立了肾脏病数据系统(USRDS),使监测数据更为准确。美国大学的Rosansky教授着眼于ESRD开始透析时机,对美国ESRD管理系统进行了回顾,并对美国未来几十年ESRD的发病和患病趋势进行了预测。慢性肾脏病(CKD)时患者肾功能逐渐下降,达到什么程度就能被叫做ESRD?在美国初始覆盖肾脏替代治疗(RRT)时,残余肾功能(RRF)下降到原始值的5%时,患者被称为ESRD,可以接受RRT。之后用作ESRD定义的RRF值逐渐提升到原始值的10%、15%。从1996年到2009年,RRF还剩超过10%的患者即开始RRT的患者占全部开始RRT治疗患者比例从19%上升到54%。但是,最新发表的一系列观察性研究均表明了早开始透析对患者的长期存活是有害的。也许是由于这些研究结果的发布,美国ESRD发病率自2010年后呈下降趋势,同时没有观察到RRT患者死亡率的增加,提示了避免过早透析的安全性和益处。美国ESRD治疗在1981年耗资仅16亿,而2011年高达近340亿元,花费骤增的原因与治疗人数的增加不无关系。较早开始RRT是ESRD发病率和患病率升高的一个重要原因,或许延迟透析会降低RRT发病和患病率,从而降低ESRD治疗成本。据USRDS统计,75岁以上ESRD患者多较早开始透析治疗,预计至2030年该人群患者人数将翻倍。相应的,美国ESRD报销计划纳入了排除RRT的保守治疗方案,这有利于十分危重的老年患者选择保守治疗,而减少RRT的使用。

关键词：肾病 ESRD 老年患者保守治疗

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Functional brain imaging of gastrointestinal sensation in health and disease

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World j.urnal of Gastroenterology 2007年第25期13卷 3438-3445页

作者： Lukas Van Oudenhove steven j.Coen Qasim Aziz Department of Neurosciences Division of Psychiatry & Department of Pathophysiology Gastroenterology Section University Hospital Gasthuisberg University of Leuven Belgium Centre for Neuroimaging Sciences Institute of Psychiatry London United Kingdom Division of Neuroscience & Medicine Department of GI Sciences Hope Hospital University of Manchester United Kingdom

It has since long been known, from everyday experience as well as from animal and human studies, that psychological processes-both affective and cognitive- exert an influence on gastrointestinal sensorimotor function. More specifically, a link between psychological factors and visceral hypersensitivity has been suggested, mainly based on research in functional gastrointestinal disorder patients. However, until recently, the exact nature of this putative relationship remained unclear, mainly due to a lack of non-invasive methods to study the （neurobiological） mechanisms underlying this relationship in non-sleeping humans. As functional brain imaging, introduced in visceral sensory neuroscience some 10 years ago, does provide a method for in vivo study of brain-gut interactions, insight into the neurobiological mechanisms underlying visceral sensation in general and the influence of psychological factors more particularly, has rapidly grown. In this article, an overview of brain imaging evidence on gastrointestinal sensation will be given, with special emphasis on the brain mechanisms underlying the interaction between affective ＆ cognitive processes and visceral sensation. First, the reciprocal neural pathways between the brain and the gut （brain- gut axis） will be briefly outlined, including brain imaging evidence in healthy volunteers. Second, functional brain imaging studies assessing the influence of psychological factors on brain processing of visceral sensation in healthy humans will be discussed in more detail. Finally, brain imaging work investigating differences in brain responses to visceral distension between healthy volunteers and functional gastrointestinal disorder patients will be highlighted.

关键词： Functional brain imaging Functionalgastro-intestinal disorders Visceral hypersensitivity Gastrointestinal sensation Psychological factors

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Proteasome inhibition-induces endoplasmic reticulum dysfunction and cell death of human cholangiocarcinoma cells

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World j.urnal of Gastroenterology 2007年第6期13卷 851-857页

作者： Yucel Ustundag steven F Bronk Gregory j.Gores Mayo Clinic College of Medicine Rochester MN 55905 United States

AIM: To determine if proteasome inhibition induces apoptosis in human cholangiocarcinoma cells, and if so, to elucidate the cellular mechanisms. METHODS: Studies were performed in the human KMCH, KMBC, and Mz-ChA-1 cholangiocarcinoma, and normal rat cell lines. MG132, a peptide aldehyde, which inhibits the chymotrypsin-like activity of the proteaosome was employed for this study. Apoptosis was assessed morphologically by 4'-6-Diamidino-2-phenylindole (DAPI) nuclear staining and fluorescence microscopy. Mitochondrial membrane potential was examined using a fluorescent unquenching assay. Ultrastructural changes during cell death were examined using transmission electron microscopy (TEM). Caspase 3/7 activity was assessed using an enzymatic-based fluorescent assay. Cytosolic-free calcium concentrations were measured using Fura-2 and digitized fluorescent microscopy. RESULTS: MG132, a proteasome inhibitor, induced apoptosis in all the cholangiocarcinoma cell lines examined. In contrast, minimal cytotoxicity was observed in normal rat cholangiocytes. Apoptosis was time-and -concentration-dependent. There was no change in the mitochondrial membrane potential between treated and untreated cells. Ultrastructural examination by transmission electron microscopy displayed the classic features of apoptosis, but in addition, there was also dramatic vacuolization of the endoplasmic reticulum (ER). Unexpectedly, no increase in caspase 3/7 activity was observed in MG132 treated cells, nor did the pancaspase inhibitor, Q-VD-OPh prevent cell death. The protein synthesis inhibitor, cycloheximide, blocked apoptosis induced by proteosome inhibitor indicating that ER dysfunction was dependent upon the formation of new proteins. CONCLUSION: Proteosome inhibition induces ERdysfunction and caspase-independent cell death selectively in human cholangiocarcinoma cells. Proteasome inhibitors warrant evaluation as anticancer agents for the treatment of human cholangiocarcinoma.

关键词： MG132 Cholangiocarcinoma Proteosome Apoptosis Calcium

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Entropy and enthalpy for triggering cutaneous erythema

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j.urnal of Innovative Optical Health Sciences 2015年第4期8卷 54-57页

作者： steven L.j.cques j.seph T.Walsh Wellman Laboratories Massachusetts General Hospital BostonMAUSA Harvard Medical School-M.I.T. CambridgeMAUSA Oregon Health&Science University 3303 SW Bond Ave.PortlandORUSA 97239

The molar entropy(OS)and molar enthalpy(△H)for the denaturation event that triggers cutaneous erythema was determined to be △S=190j.(mole K)and△H=146.9×10^(3) j.*** experiment involved placing heated water against the skin of the forearm,for a range of termperatures and exposure *** the skin to 45℃ for 22 s was at the threshold for producing erythema,which was similar to the threshold for a slight degree of pain.

关键词： Skin erythema thermal entropy enthalpy

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