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Current strategies for reproductive management of gilts and sows in North America

Journal of Animal Science and Biotechnology 2015年第2期6卷 191-204页

作者： robert r kraeling Stephen K Webel L&r research Associates JBS United Animal Health

Many advances in genetic selection, nutrition, housing and disease control have been incorporated into modern pork production since the 1950s resulting in highly prolific females and practices and technologies, which significantly increased efficiency of reproduction in the breeding herd. The objective of this manuscript is to review the literature and current industry practices employed for reproductive management. In particular the authors focus on assisted reproduction technologies and their application for enhanced productivity. Modern maternal line genotypes have lower appetites and exceptional lean growth potential compared to females of 20 yr ago. Thus, nutrient requirements and management techniques and technologies, which affect gilt development and sow longevity, require continuous updating. Failure to detect estrus accurately has the greatest impact on farrowing rate and litter size. Yet, even accurate estrus detection will not compensate for the variability in the interval between onset of estrus and actual time of ovulation. However, administration of GnrH analogs in weaned sows and in gilts after withdrawal of altrenogest do overcome this variability and thereby synchronize ovulation, which makes fixed-time AI practical. Seasonal infertility, mediated by temperature and photoperiod, is a persistent problem. Training workers in the art of stockmanship is of increasing importance as consumers become more interested in humane animal care. Altrenogest, is used to synchronize the estrous cycle of gilts, to prolong gestation for 2-3 d to synchronize farrowing and to postpone post-weaning estrus. P.G. 600~ is used for induction of estrus in pre-pubertal gilts and as a treatment to overcome seasonal anestrous. Sperm cell numbers/dose of semen is significantly less for post cervical AI than for cervical AI. real-time ultrasonography is used to determine pregnancy during wk 3-5. PGF2a effectively induces farrowing when administered within two d of normal gestati

关键词： Gilts Management Nutrition reproductive technology Sows

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后备母猪培育和管理

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国外畜牧学（猪与禽） 2018年第9期38卷 1-4页

作者：李洪宇(译) 陈建康(校) 靳文广(制图) robert r kraeling stephen k webel 不详美国l&r研究会美国jbs联合动物保健公司

自20世纪50年代起,基因选择、营养、饲养设施和疾病控制等诸多研究进展已经被应用到现代猪肉生产中,从而产生了高产母猪和相关的管理措施与技术。本文的目的是综述应用于繁殖管理方面的文献和最新的行业生产技术,尤其是重点评述辅助繁... 详细信息

自20世纪50年代起,基因选择、营养、饲养设施和疾病控制等诸多研究进展已经被应用到现代猪肉生产中,从而产生了高产母猪和相关的管理措施与技术。本文的目的是综述应用于繁殖管理方面的文献和最新的行业生产技术,尤其是重点评述辅助繁殖技术及其在提高母猪生产力上的应用情况。与20年前的母猪相比,现代母系猪种食欲较低,但瘦肉的生长潜力较高。因此,会影响后备母猪发育和使用年限的营养需求、管理技术和生产工艺需要持续的更新。不能准确地确定母猪的发情会严重影响母猪的分娩率和窝产仔数。然而,即使能够准确地确定母猪发情也不能消除由发情开始至实际排卵之间的时间间隔差异所造成的影响。然而,在停用烯丙孕素之后,给断奶母猪和后备母猪服用促性腺激素释放激素类似物,能克服这种差异,因此能够引发母猪同步排卵,这使养猪场能够对繁育母猪定期进行人工授精。受温度和光周期调控影响的季节性不孕是养猪生产中一个持续存在的问题。随着消费者对动物福利越来越重视,对养殖场员工进行技能培训显得越来越重要。用于后备母猪同步发情的烯丙孕素可以使母猪的妊娠期延长2 d～3 d,以使群内母猪能够同步分娩和推迟断奶后的发情。P.G.600可以用来诱导初情期前的后备母猪发情,并可治疗季节性乏情。与子宫颈授精相比,子宫内授精(即深部输精)对每份精液或每次授精所需的精子数明显减少。在人工授精后3～5周,实时超声检查可以查明母猪是否妊娠。在正常的预产期前2 d,前列腺素F2α能有效诱导母猪分娩。同步排卵、单次定期人工授精和诱导生产可使母猪同步分娩,这有助于养猪场进行生产管理,并可减少死胎,降低仔猪死亡率。人工接产和助产对确保仔猪在出生后能够及时吃到充足数量的初乳是非常重要的。本综述还提出了新的性能术语。

关键词：后备母猪管理营养繁殖技术经产母猪

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Sleep as a window to understand and regulate Alzheimer's disease:emerging roles of thalamic reticular nucleus

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Neural regeneration research 2025年第6期20卷 1711-1712页

作者： Haoqi Sun Shiqian Shen robert J.Thomas M.Brandon Westover Can Zhang Department of Neurology Beth Israel Deaconess Medical CenterHarvard Medical SchoolBostonMAUSA Center for Translational Pain research Department of AnesthesiaCritical Care and Pain MedicineMassachusetis General HospitalHarvard Medical SchoolBostonMAUSA Division of Pulmonary Critical Care and Sleep MedicineDepartment of MedicineBeth Israel Deaconess Medical CenterHarvard Medical SchoolBostonMAUSA Genetics and Aging research Unit McCance Center for Brain HealthMass General Institute for Neurodegenerative DiseaseDepartment of NeurologyMassachusetts General HospitalHarvard Medical SchoolBostonMAUSA

Introduction:Alzheimer 's disease(AD) is a common neurodegenerative disorder and the primary cause of dementia. Considerable evidence supports the “amyloid hypothesis,” stating that the pathogenesis of AD is primarily caused by the deposition of amyloid-β(Aβ), which drives tau phosphorylation, neuroinflammation, and neurodegeneration in the brain. The amyloid hypothesis is strengthened by the significant and moderate benefit of lecanemab, a humanized antibody through an anti-amyloid mechanism,showing slowed clinical decline(van Dyck et al.,2023). The recent positive results of anti-amyloid trials have brought back focus on the amyloid hypothesis through biochemical, genetic, and pharmacological approaches(Zhang, 2023).

关键词： Alzheimer inflammation hypothesis

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糖酵解和脂肪酸氧化抑制剂对摘除卵巢猪血清促黄体素和葡萄糖的影响

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南京农业大学学报 2001年第1期24卷 73-76页

作者：雷治海 C r Barb r r kraeling 南京农业大学动物医学院 rBrussellAgriculturalresearchCenter USDAARSAthensGA30613USA

研究了急性能量阻断对血清促黄体素和葡萄糖的影响。选用美国佐治亚州雅森斯当地杂交青年母猪 2 0头 ,体重(5 9 7± 10 2 )kg ,12 0～ 130日龄。实验前两周摘除卵巢 ,随机分为 4组 ,每组 5头 :①生理盐水组 (对照 ) ;②糖酵解抑制剂组 ... 详细信息

研究了急性能量阻断对血清促黄体素和葡萄糖的影响。选用美国佐治亚州雅森斯当地杂交青年母猪 2 0头 ,体重(5 9 7± 10 2 )kg ,12 0～ 130日龄。实验前两周摘除卵巢 ,随机分为 4组 ,每组 5头 :①生理盐水组 (对照 ) ;②糖酵解抑制剂组 (2 脱氧 D 葡萄糖 ,2DG ,40 0mg·kg-1) ;③脂肪酸氧化抑制剂组 (巯基乙酸盐 ,MA ,2 0 0mg·kg-1) ;④ 2DG +MA组。通过颈静脉给药。给药前 2h至给药后 6h经颈静脉导管每 15min采血样一次。次日分离血清后 ,用葡萄糖氧化酶试剂盒定量分析血清葡萄糖浓度 ,用放射免疫分析法 (rIA)定量分析血清促黄体素 (LH)。结果如下 :(1)与对照组比较 ,注射 2DG和 2DG +MA后 ,血清葡萄糖浓度显著升高(P <0 0 5 ) ,而注射MA后未见明显变化。 2DG +MA处理对血清葡萄糖浓度的影响大于 2DG。 (2 )与处理前期相比 ,2DG和 2DG +MA抑制了LH的分泌 ,而生理盐水和MA处理未影响LH的分泌。注射 2DG和 2DG +MA后 ,平均和基础血清LH的浓度低于注射生理盐水组 (P <0 0 2 ) ;但LH的脉冲频率和幅度不受上述处理的影响。实验结果表明。

关键词：葡萄糖促黄体素猪糖酵解抑制剂脂肪酸氧化抑制剂抗代谢药物急性能量阻断

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Conditions for advantageous quantum Bitcoin mining

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Blockchain(research and Applications) 2023年第3期4卷 52-63页

作者： robert r.Nerem Daya r.Gaur Institute for Quantum Science and Technology University of CalgaryAlbertaT2N 1N4Canada Department of Mathematics University of California San DiegoCalifornia92093United States Department of Mathematics and Computer Science University of LethbridgeAlbertaT1K 3M4Canada

Our aim is to determine the conditions for quantum computing technology to give rise to the security risks associated with quantum Bitcoin ***,we determine the speed and energy efficiency a quantum computer needs to offer an advantage over classical *** analyze the setting in which the Bitcoin network is entirely classical except for a single quantum miner with a small hash rate compared to the *** develop a closed-form approximation for the probability that the quantum miner successfully mines a block,with this probability dependent on the number of Grover iterations the quantum miner applies before making a ***,we show that for a quantum miner that is“peaceful”,this success probability is maximized if the quantum miner applies Grover iterations for 16 min before measuring,which is surprising,as the network mines blocks every 10 min on *** this optimal mining procedure,we show that the quantum miner outperforms a classical computer in efficiency(cost per block)if the condition Qrb is satisfied,where Q is the cost of a Grover iteration,C is the cost of a classical hash,r is the quantum miner's speed in Grover iterations per second,and b is a factor that attains its maximum if the quantum miner uses our optimal mining *** condition lays the foundation for determining when quantum mining and the known security risks associated with it will arise.

关键词： Quantum algorithms Quantum mining Grover search Bitcoin Quantum attacks

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Impact of a physician-supervised exercise-nutrition program with testosterone substitution in partial androgen-deficient middle-aged obese men

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Journal of Geriatric Cardiology 2011年第4期8卷 201-206页

作者： Ernst r Schwarz robert D Willix Jr Cenegenics Education and research Foundation Las Vegas and Heart Institute of Southern CaliforniaBeverly Hills348 S Oakhurst DrBeverly HillsCA 90212USA

Background Partial androgen deficiency syndrome in the aging male is associated with signs of aging such as a development of abdominal obesity,sexual dysfunction,increase body fat,weight gain and the development of cardiac *** We assessed the outcome of a commercially available physician supervised nutrition and exercise program with concomitant testosterone replacement therapy in middle age obese men with partial androgen deficiency in order to reduce cardiac risks *** Fifty-six self referred men without diabetes mellitus,hypertension,or cardiovascular disease(ages 52.3±7.8 years)were randomly selected from a large *** weight,body fat composition,fasting glucose,hemoglobin A1c and fasting lipid levels,as well as free and total testosterone levels were *** patients were assessed and followed 6–18 months after initiation of the *** program consisted of a low glycemic load balanced nutrition diet,a recommended structured daily exercise program of 30–60 minutes,as well as once to twice weekly intramuscular testosterone injections(113.0±27.8 mg).results At follow up,weight was reduced from 233.9±30.0 pounds(lbs)to 221.3±25.1 lbs(Preduced from 33.2±3.3 kg/m2 to 31.3±2.8 kg/m^(2)(Preduced from 95.3±14.4 mg/dL to 87.5±12.6 mg/dL(Prol was reduced from 195.4±33.0 mg/dL to 172.7±35.0 mg/dL(Prse events were *** Testosterone replacement therapy in middle aged obese men with partial androgen deficiency appeared safe and might have promoted the effects of a weight reduction diet and daily exercise program as long as an adequate physician supervision and follow up was *** combination therapy significantly reduced coronary risk factors such as glucose intolerance and hyperlipidemia.

关键词： aging heart disease androgen deficiency testosterone

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Skeletal phenotypes in secreted frizzled-related protein 4 gene knockout mice mimic skeletal architectural abnormalities in subjects with Pyle's disease from SFrP4 mutations

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Bone research 2023年第1期11卷 193-200页

作者： robert Brommage Jeff Liu David r.Powell Department of Metabolism research Lexicon PharmaceuticalsThe WoodlandsTX77381USA

Mutations in SFrP4 cause Pyle’s bone disease with wide metaphyses and increased skeletal *** WNT signaling pathway plays important roles in determining skeletal architecture and SFrP4 is a secreted Frizzled decoy receptor that inhibits WNT *** cohorts of male and female Sfrp4 gene knockout mice,examined through 2 years of age,had a normal lifespan but showed cortical and trabecular bone *** human Erlenmeyer flask deformities,bone cross-sectional areas were elevated 2-fold in the distal femur and proximal tibia but only 30%in femur and tibia *** cortical bone thickness was observed in the vertebral body,midshaft femur and distal *** trabecular bone mass and numbers were observed in the vertebral body,distal femur metaphysis and proximal tibia *** femurs retained extensive trabecular bone through 2 years of *** bodies had increased compressive strength,but femur shafts had reduced bending ***,but not cortical,bone parameters in heterozygous Sfrp4mice were modestly *** resulted in similar declines in both cortical and trabecular bone mass in wild-type and Sfrp4 KO ***4 is critical for metaphyseal bone modeling involved in determining bone ***4 KO mice show similar skeletal architecture and bone fragility deficits observed in patients with Pyle’s disease with SFrP4 mutations.

关键词： SFrP4 skeletal elevated

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On-board measurement of emissions from liquefied petroleum gas,gasoline and diesel powered passenger cars in Algeria

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Journal of Environmental Sciences 2014年第8期26卷 1651-1659页

作者： Saadane Chikhi Ménouèr Boughedaoui rabah Kerbachi robert Joumard Department of Industrial Chemistry Faculty of TechnologyUniversity of Blida 1Route de SoumaaBlida 09000Algeria Environmental Science and Technology Laboratory National Polytechnic School of AlgiersAlgiers 16200Algeria Transport and Environment Laboratory IfsttarBronFrance

On-board measurements of unit emissions of CO,HC,NOx and CO2 were conducted on 17 private cars powered by different types of fuels including gasoline,dual gasoline–liquefied petroleum gas（LPG）,gasoline,and diesel. The tests performed revealed the effect of LPG injection technology on unit emissions and made it possible to compare the measured emissions to the European Artemis emission model. A sequential multipoint injection LPG kit with no catalyst installed was found to be the most efficient pollutant reduction device for all of the pollutants,with the exception of the NOx. Specific test results for a sub-group of LPG vehicles revealed that LPG-fueled engines with no catalyst cannot compete with catalyzed gasoline and diesel engines. Vehicle age does not appear to be a determining parameter with regard to vehicle pollutant emissions. A fuel switch to LPG offers many advantages as far as pollutant emissions are concerned,due to LPG＇s intrinsic ***,these advantages are being rapidly offset by the strong development of both gasoline and diesel engine technologies and catalyst converters. The LPG＇s performance on a chassis dynamometer under real driving conditions was better than expected. The enforcement of pollutant emission standards in developing countries is an important step towards introducing clean technology and reducing vehicle emissions.

关键词： Unit emission Pollutant Vehicle On-board measurement LPG Gasoline Diesel

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Assessment of mercury(II) bioavailability using a bioluminescent bacterial biosensor: Practical and theoretical challenges

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Journal of Environmental Sciences 2010年第8期22卷 1137-1143页

作者： Paulo r G Barrocas William M Landing robert J M Hudson Department of Sanitation and Environmental Health National School of Public Health Oswaldo Cruz Foundation Department of Oceanography Florida State University. Tallahassee Department of Natural resources and Environmental Sciences University of Illinois

Critical methodological challenges in the microbial biosensor approach to assessing Hg（II） bioavailability were evaluated from the perspective of analytical chemists. The main challenge stems from the fact that the chemical speciation of Hg（II） in natural waters exerts a major control on its bioavailability, yet its natural complexation equilibria are extensively altered during conventional bioassays. New data, obtained using a bioluminescent Hg（II）-biosensor, that illustrate these challenges are presented and potential solutions proposed.

关键词： mercury bioavailability biosensor chemical speciation bioluminescent

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Functional Interaction of the SNArE Protein NtSyp121 in Ca^2＋ Channel Gating, Ca^2＋ Transientsand ABA Signalling of Stomatal Guard Cells

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Molecular Plant 2008年第2期1卷 347-358页

作者： Sergei Sokolovski Adrian Hills robert A. Gay Michael r. Blatt Laboratory of Plant Physiology and Biophysics IBLS--Plant Sciences University of Glasgow Glasgow G12 8QQ UK Current address: Blackfriars 64 St Giles Oxford OX1 3LY UK

There is now growing evidence that membrane vesicle trafficking proteins, especially of the superfamily of SNArEs, are critical for cellular signalling in plants. Work from this laboratory first demonstrated that a soluble, inhibitory （dominant-negative） fragment of the SNArE NtSyp121 blocked K^＋ and CI^- channel responses to the stress-related hormone abscisic acid （ABA）, but left open a question about functional impacts on signal intermediates, especially on Ca^2＋-mediated signalling events. Here, we report one mode of action for the SNArE mediated directly through alterations in Ca^2＋ channel gating and its consequent effects on cytosolic-free [Ca^2＋] （[Ca^2＋]i） elevation. We find that expressing the same inhibitory fragment of NtSyp121 blocks ABA-evoked stomatal closure, but only partially suppresses stomatal closure in the presence of the NO donor, SNAP, which promotes [Ca^2＋]i elevation independently of the plasma membrane Ca^2＋ channels. Consistent with these observations, Ca^2＋ channel gating at the plasma membrane is altered by the SNArE fragment in a manner effective in reducing the potential for triggering a rise in [Ca^2＋]i, and we show directly that its expression in vivo leads to a pronounced suppression of evoked [Ca^2＋]i transients. These observations offer primary evidence for the functional coupling of the SNArE with Ca^2＋ channels at the plant cell plasma membrane and, because [Ca^2＋]i plays a key role in the control of K^＋ and CI^- channel currents in guard cells, they underscore an important mechanism for SNArE integration with ion channel regulation during stomatal closure.

关键词： Ca^2+ channel, hyperpolarization-activated abscisic acid membrane vesicle traffic cytosolic-free [Ca^2+]elevation Nicotiana plant pathogen defense.

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