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Bovine Sperm Motility as Af.ected by Alpha Tocopherol and Ascorbic Acid during Storage

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Advances in Reproductive Sciences 2019年第2期7卷 39-49页

作者： Ryan Page charles rosenkrans jr. Department of.Animal Science Division of Agriculture University of Arkansas System Fayetteville AR USA

Our purpose was to determine the impact of.ascorbic acid and α-tocopherol on bovine sperm motility f.llowing short-term storage or cryopreservation. Semen was collected f.om mature Angus bulls (n = 4). The experimental design was a randomized complete block, with bull serving as block, and treatments were structured as a 4 × 4 f.ctorial with f.ur concentrations of.ascorbic acid (0, 5, 10, 20 mM) and f.ur concentrations of.α-tocopherol (0, 0.05, 0.5, 5 mM). Sperm motility characteristics were evaluated using computer assisted sperm analyses at 0, 4, and 8 h of.incubation (39?C) and post-cryopreservation. Initial sperm motility was (79.6% ± 1.6) and decreased to (6.1% ± 1.6%) af.er cryopreservation. Cryopreserved spermatozoa had lower (P P > 0.1) by α-tocopherol. Addition of.20 mM ascorbic acid to storage media decreased (P P α-tocopherol. Stepwise regression models predicted (P α-tocopherol was not benef.cial f.r short-term storage of.spermatozoa;however, our results were inconclusive with regards to inclusion of.ascorbic acid and α-tocopherol in egg yolk-based cryopreservation media.

关键词： Bull Spermatozoa Antioxidants Cryopreservation

Ergot Alkaloid Ef.ects on Bovine Sperm Motility <i>In Vitro</i>

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Advances in Reproductive Sciences 2019年第1期7卷 7-15页

作者： Ryan Page Toby Lester Rick Rorie charles rosenkrans jr. Department of.Animal Science Division of Agriculture University of Arkansas System Fayetteville Arkansas USA

Cattle in some parts of.the world graze pastures that consist of.tall f.scue that may contain ergot alkaloid contamination. Those ergot alkaloids are associated with reduced reproductive rates in cattle. Our objective was to determine if.ergot alkaloids [dihydroergotamine (DHET), ergonovine (EN), and ergotamine (ET)] directly af.ect bovine sperm characteristics. Spermatozoa were collected f.om mature Angus (n = 2) and Balancer (n = 4) bulls. Within bull, treatments were structured as a 3 × 5 f.ctorial with three alkaloids (DHET, EN, and ET) and f.ve concentrations of.each alkaloid (0, 33, 66, 100, or 200 μM). Spermatozoa (25 × 106) were incubated (39?C) in 1 mL of.modif.ed sperm medium. Sperm motility characteristics were evaluated using CASA (Hamiliton Thorne IVOS, Beverly, MA) at 0, 3, and 6 h af.er initial alkaloid exposure. Initial sperm motility was (69% ± 1.1%) and declined (P = 0.01) to (35% ± 2.6%) at 6 h. Sperm motility decreased (P P f.how ergot alkaloids may hinder cattle reproductive rates.

关键词： CASA Bull Spermatozoa Toxins

f.rage and breed ef.ects on behavior and temperament of.pregnant beef.heif.rs

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Journal of.Animal Science and Biotechnology 2013年第3期4卷 165-169页

作者： Angela R Mays Michael L Looper Benjamin C Williamson Kenneth P Cof.ey Wayne K Coblentz Glen E Aiken charles f.rosenkrans jr Department of.Animal Science University of ArkansasFayetteville AR 72701 USA Department of.Agricultural Sciences Morehead StateUniversity327 Reed Hall Morehead KY 40351 USA USDA-ARS US Dairy Forage Research CenterMarshfield WI 54449 USA USDA-ARS Forage Animal Production Research UnitLexingtonKY 40546 USA

Background： Integration of.behavioral observations with traditional selection schemes may lead to enhanced animal well-being and more prof.table f.rage-based cattle production ***-inf.uenced（BR;n = 64） and Gelbvieh × Angus（GA;n = 64） heif.rs consumed either toxic endophyte-inf.cted tall f.scue（E＋） or one of.two nontoxic endophyte-inf.cted tall f.scue（NT） cultivars during two *** were weighed at midpoint and termination of.*** behavior（grazing,resting in the shade,lying,or standing without grazing） was recorded（n = 13 visual observations per yr in June and July） f.r each *** yr 2,exit velocity（EV） and serum prolactin（PRL） were ***： Grazing behavior was inf.uenced（P 0.05） by an interaction between f.scue cultivar and breed *** × Angus heif.rs assigned to E＋ pastures had the lowest percentage of.animals grazing and the largest percentage of.animals resting in the ***-inf.uenced heif.rs had f.ster EV（P 0.001） than GA heif.rs（0.52 vs.0.74 ± 0.04 s/m,respectively）.Body weight（BW） was af.ected（P 0.01） by an interaction of.tall f.scue cultivar and d,and an interaction of.tall f.scue cultivar and breed *** grazing NT pastures were heavier（P 0.01） than heif.rs grazing E＋ pastures at midpoint and *** × Angus heif.rs grazing NT pastures were heavier（P 0.01） than GA and BR heif.rs grazing E＋ and BR heif.rs grazing NT *** interaction of.f.rage cultivar and breed type occurred on serum PRL（P 0.01）.Conclusion： Collectively f.scue cultivar,EV,and concentrations of.serum PRL were associated with grazing *** grazing NT pastures were observed to be grazing more than heif.rs assigned to E＋ pastures,regardless of.breed type,which may have contributed to changes in BW and average daily gain（ADG） in *** of.behavioral observations along with traditional selection schemes may lead to enhanced animal well-being and more prof.table f.rage-based cattle prod

关键词： Cattle Endophyte-inf.cted tall f.scue Grazing behavior Prolactin Temperament

Interaction of.ergotamine with liver Cytochrome P450 3A in rats

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Agricultural Sciences 2012年第6期3卷 795-798页

作者： Ali S. Moubarak Hehai Wang Zelpha B. Johnson charles f. rosenkrans Department of.Animal Science University of Arkansas Fayetteville AR 72701

This study was conducted to investigate the ef.ect of.the ergot alkaloid, ergotamine (ET), on the induction of.CYP3A and the interaction in vivo and in vitro with ET. Sprague-Dawley rats were treated intraperitoneally f.r 4 days as f.llows: control (injecting with 0.5 ml of.only corn oil);dexamethasone treatment (injecting with 100mg/kg of.dexamethasone in corn oil);and ergotamine treatment (injecting with 100mg/kg of.ergotamine in corn oil). Liver tissues were collected f.om each group (n = 5, total of.30 rats) and liver microsomes were prepared. Cytochrome CYP3A activity was evaluated using ET and its isomer as substrates in medium containing liver microsomes and NADPH at 37℃ f.r 30 min. HPLC was used to measure the disappearance of.the substrate and the appearance of.the metabolites. Liver microsomes f.om rats pretreated with dexamethasone were f.ve times more (P 0.05) in activity of.CYP3A when compared to the control group (5.2 vs. 7.0 nM ET/min/mg protein;SE = 4.83) or ET isomer (1.5 vs. 4.7 nM ET isomer/ min/mg protein;SE = 1.70). When ketoconazole was used as specif.c inhibitor of.CYP3A, ergotamine metabolisms were inhibited in a dose dependent f.shion reaching a maximum at an inhibitor to substrate ratio of.greater than one and LD50 at 0.5 nM of.ketoconazole/mg protein. The data presented in this study suggest that although the ergot alkaloids ergotamine and its isomer are ideal substrates f.r the isozyme CYP3A, these compounds have no ef.ect on the induction of.CYP3A af.er 4 days of.treatment.

关键词： Microsomes Liver Rat

f.ndamentals of.logic design : :5th ed. / 5th ed.

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Ef.ects of.Land Use on Greenhouse Gas f.ux in Playa Wetlands and Associated Watersheds in the High Plains, USA

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2003年

作者： Roth charles H. jr.

本书详细地阐述了理解逻辑设计基本概念所必需的理论, 同时又不过多地讨论开关理论的数学证明, 全书共分20个单元, 包括布尔代数、逻辑门设计、触发器、状态机等基本概念。

ISBN: (纸本)7111123514

关键词： Logic design.

来源：畅想之星图书光盘版（南... 评论

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Agricultural Sciences 2019年第2期10卷 181-201页

作者： Dale W. Daniel Loren M. Smith Scott T. McMurry Brian A. Tangen charles f. Dahl Ned H. Euliss jr. Ted LaGrange Department of.Integrative Biology Oklahoma State University Stillwater OK USA U.S. Geological Survey Northern Prairie Wildlife Research Center Jamestown ND USA Nebraska Game & Parks Commission Wetlands Program Lincoln NE USA

In the High Plains, U.S., native prairie conversion to cropland agriculture has resulted in a loss of.service delivery capabilities f.om most depressional wetlands as a result of.sedimentation. Restoring historic hydrological conditions to af.ected wetlands may rejuvenate some services, however, there may be tradeof.s due to emissions of.CH4 and N2O. We evaluated the inf.uence of.two predominant conservation programs (Wetlands Reserve Program, WRP and Conservation Reserve Program, CRP) on gas emissions (CO2, CH4, N2O) f.om 42 playas and uplands in the High Plains of.Nebraska. Because playa restoration through the WRP is most prevalent in the Rainwater Basin (RWB), we studied 27 playas/uplands among ref.rence condition, cropland, and WRP land uses. We studied 15 playas/uplands within native grassland, cropland, and CRP land uses in the Western High Plains (WHP) of.Nebraska. Emissions were collected bi-weekly f.om April-October of.2012 and 2013 f.om f.ur landscape positions extending outward f.om the wetland center into upland. In RWB playas, CH4 and N2O emissions were similar among land uses but CO2 was 28% higher in cropland than WRP wetlands. Cropland uplands emitted 648% more N2O than ref.rence and WRP uplands. Overall, net CO2-equiv emissions were lower in playas/uplands in WRP, suggesting that benef.ts of.playa restoration may include climate mitigation services as well as increased water storage capacity and biodiversity provisioning. In the WHP, cropland and grassland playas emitted 46 and 23 times more CH4, respectively, than CRP in 2013. Playas in CRP emitted 43% less N2O than cropland playas. In 2013, net emissions f.r cropland and native grassland playas were 75% and 39% greater, respectively, than CRP playas. In the WHP, the benef.ts of.lower gas emissions must be appropriately weighted against tradeof.s of.ecosystem services related to shorter hydroperiods as a result of.reduced runof. into playas in CRP.

关键词： Conservation Reserve Program Depressional Wetlands Ecosystem Services Global Climate Change Wetlands Reserve Program Wetland Restoration

美国在CIMT2003展出的主要产品及其特点

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世界制造技术与装备市场 2003年第2期 179-181页

作者： charles f.Carter jr. 美国AMT前副主席

美国机械制造技术协会(AMT)是美国机床工业的贸易组织.AMT的前身就是成立于1902年的美国机床制造者协会(NMTBA).

关键词： CIMT2003 美国机械制造技术协会 AMT 展览会

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机床的技术发展趋势

世界制造技术与装备市场 1998年第1期 73-74页

作者： charles f.Carter jr.,延祐美国制造技术协会技术副总裁

本文将分几个段落来对90年代后半期的技术发展趋势对机床工业的影响作一些评述。控制器,特别是那些基于计算机的控制器,其日益增长的重要性,是机床设计考虑中的一个主要因素。当然,对机械设计也不可忽略。一种全新的,基于STEWART平台... 详细信息

本文将分几个段落来对90年代后半期的技术发展趋势对机床工业的影响作一些评述。控制器,特别是那些基于计算机的控制器,其日益增长的重要性,是机床设计考虑中的一个主要因素。当然,对机械设计也不可忽略。一种全新的,基于STEWART平台的结构的出现,就是机械设计革新的例子。

关键词：机床轴承 DN 陶瓷滚珠直线电机

The Ef.ect of.Non-Invasive Goal Directed f.uid Administration on Graf. f.nction in Deceased Donor Renal Transplantation: A Pilot Study

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Open Journal of.Organ Transplant Surgery 2016年第3期6卷 13-21页

作者： Joseph R. Whiteley Jason M. Taylor John J. f.eely jr. Thomas I. Epperson Laura Bell John L. Murray IV charles f. Bratton William R. Hand Department of.Anesthesia and Perioperative Medicine Medical University of South Carolina Charleston USA Department of.Anesthesiology Columbia University Medical Center New York USA Medical University of.South Carolina College of.Medicine Charleston USA Department of.Surgery Division of Transplant Surgery Charleston USA

Background: Non-invasive goal directed f.uid therapy during deceased donor renal transplant (CRT) may reduce the incidence of.delayed graf. f.nction. Plethysmograph Variability Index (PVI) has been shown to predict f.uid responsiveness during surgery. This pilot study evaluated the f.asibility of.goal directed f.uid administration protocol based upon PVI studying the incidence of.delayed graf. f.nction (DGf. in renal transplant recipients. Methods: Twenty patients underwent primary CRT. The Control group received intravenous f.uid (IVf. at a calculated constant rate. The Treatment group received a baseline IVf.inf.sion throughout the surgery. PVI values greater than 13% were treated with 250 ml boluses of.IVf. Primary end point was DGf.total IVf.administration and urinary biomarker NGAL levels were secondary endpoints. Results: Treatment group at every time point received signif.cantly less IVf. There was no signif.cant dif.erence in incidence of.DGf.between the groups. 2 patients in the Control group and 6 in the Treatment group developed DGf. NGAL was not associated with the group assignment or total IVf.given (p f.ectiveness of.goal directed f.uid therapy with non-invasive dynamic parameters has not been validated in renal transplant surgery and larger prospective studies are needed to determine its utility in renal transplantation.

关键词： Deceased Donor Renal Transplant Non-Invasive Goal Directed f.uid Therapy Delayed Graf. f.nction Plethysmograph Variability Index