检索结果-南通市图书馆

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

高产奶牛的能量需要

中国畜牧兽医 1986年第2期 33-35页

作者：蒋必光 j.t.huber

奶牛日粮能量供给不当是奶牛饲养中的一个严重问题。通常是泌乳早期营养不足,或者泌乳后期和干奶期营养过剩引起过肥和其后的代谢障碍,除能量的数量以外,能量的来源也影响产奶量和奶的组成。本文着重讨论不同营养水平的影响。高产奶牛... 详细信息

奶牛日粮能量供给不当是奶牛饲养中的一个严重问题。通常是泌乳早期营养不足,或者泌乳后期和干奶期营养过剩引起过肥和其后的代谢障碍,除能量的数量以外,能量的来源也影响产奶量和奶的组成。本文着重讨论不同营养水平的影响。高产奶牛的能量需要高产奶牛在泌乳早期应供给优质可口的精

关键词：奶牛饲养产奶量泌乳早期产乳量高产奶牛干奶期

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

奶牛对蛋白质的需要和利用

中国奶牛 1983年第3期 74-79页

作者： j.t.huber Limin Kung jR 郭卓元

以往25年中,关于奶牛对蛋白质的需要了解已甚多,并已在生产中应用。本文引用近些年关于这个问题的研究资料,综述如下。一、不同生理状况的奶牛对蛋白质的需要蛋白质被分解为氨基酸,它对于机体的机能是必需的。反刍动物所需要的氨基酸可... 详细信息

以往25年中,关于奶牛对蛋白质的需要了解已甚多,并已在生产中应用。本文引用近些年关于这个问题的研究资料,综述如下。一、不同生理状况的奶牛对蛋白质的需要蛋白质被分解为氨基酸,它对于机体的机能是必需的。反刍动物所需要的氨基酸可以直接从日粮、瘤胃微生物或内源性

关键词：蛋白质母牛产奶量产乳量瘤胃降解奶牛

Facies analysis and palaeoecology of the jurassic Spiti Shale Formation in the Spiti area,Northern India

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

journal of Palaeogeography 2021年第4期10卷 438-462页

作者： franz t.Fürsich Matthias Alberti Dhirendra K.Pandey Ketan Chaskar Suraj Bhosale FG Palaoumwelt GeoZentrum Nordbayern der Friedrich-Alexander-Universitat Erlangen-NürnbergLoewenichstrasse 2891054ErlangenGermany State Key Laboratory for Mineral Deposits Research School of Earth Sciences and EngineeringCentre for Research and Education on Biological Evolution and Environment and Frontiers Science Center for Critical Earth Material CyclingNanjing210023China Department of Geology Under the School of EarthBiological and Environmental ScienceCentral University of South BiharSH 7Gaya-Panchanpur RoadVillage KarharaPost FatehpurGaya824236BiharIndia Department of Earth and Environmental Science K.S.K.V.Kachchh UniversityBhuj370001India

the Spiti Shale Formation is a widely distributed stratigraphic unit of the passive northern margin of the Indian craton,deposited between the Callovian and earliest *** siliciclastic strata are dominated by dark-grey to black argillaceous *** the formation has undergone intense tectonic stress involving folding and faulting,it is very difficult to document a complete *** the type area,the Spiti Valley,six sections have been measured that document parts of the three informal members of the formation,the Lower,Middle,and Upper *** its uniform appearance,eight facies/biofacies types could be distinguished,ranging from the anoxic shale facies,with ammonites and belemnites as the only faunal elements,to the dysoxic Malayomaorica and Bositra biofacies,and the oxic to anoxic offshore shelf facies,which are characterized by low-diversity macrobenthos *** facies are the condensed glauconiticphosphoritic mudrock facies and the Fe-oolitic siltstone facies(both characterized by sediment starvation),the aerated argillaceous silt-sandstone facies,and the tide-influenced nearshore shelf *** benthic macrofauna represents four bivalve-dominated associations all characterized by a very low to low species *** are the Bositra buchii,the Australobuchia spitiensis,the Palaeonucula cuneiformis-Pruvostiella hermanni-Indogrammatodon egertonianus,and the Malayomaorica sp.-Australobuchia spitiensis-Retroceramus haasti *** and macrobenthic associations indicate that the Spiti Shale Formation represents outer to inner shelf environments,which for much of the time were subjected to upwelling and anoxic to dysoxic *** shallowing at the top characterizes the transition to the overlying Lower Cretaceous Giumal Formation.

关键词： jurassic palaeoenvironments Biofacies Macrobenthic communities Black shales Deoxygenation Upwelling Himalayan mountains

Geochemical Signatures of Early Paleogene Source Rocks in the Sanshui Basin, South China

在线全文

学校读者我要写书评

暂无评论

Acta Geologica Sinica(English Edition) 2010年第1期84卷 145-154页

作者： LIU Chunlian franz t. FURSICH CHEN Ling CHE Xiaoguang WU jie Department of Earth Sciences Sun Yat-Sen University Guangzhou 510275 China GeoZentrum Nordbayern der Universitgit Erlangen Erlangen D-91054 Germany

the Honggang member of the early Paleogene Buxin Formation is the main source rock in the Sanshui Basin, characterized by organic-rich black shales with the cyclic recurrence of organic- poor sediments. the geochemical characteristics of the Honggang member have been documented to determine the organic matter types and depositional environments in this paper. the organic matter of the black shales mainly consists of a mixture of land plant-derived and phytoplankton-derived organic matter. total organic carbon content （tOC）-sulfur-iron （Fe） relationships suggest that the organicrich black shales were deposited under dysoxic-to-euxinic water conditions. the time that iron minerals remained in contact with H2S in anoxic waters possibly influenced the formation of syngenetic pyrite, and organic carbon controlled the formation of diagenetic pyrite. Organic-poor intervals usually show pyrite sulfur enrichment and higher degree of pyritization values relative to low organic carbon contents. this resulted from HS- diffusing downward from overlying organic-rich sediments and formed Fe sulfides through reactions with sufficient Fe. trace elements generally exhibit low concentrations and little tOC dependence, suggesting some degree of depletion in these elements in the early Paleogene sediments of the Sanshui Basin. this probably resulted from cyclic recurrences of oxic benthic conditions, which promoted the remobilization of trace elements and caused the low concentration of trace elements.

关键词： organic matter type carbon-sulfur-iron relationship trace element black shale SanshuiBasin

Subpopulations of regulatory t cells are associated with subclinical atherosclerotic plaques,levels of LDL,and cardiorespiratory fitness in the elderly

在线全文

学校读者我要写书评

暂无评论

journal of Sport and Health Science 2024年第3期13卷 288-296,I0002页

作者： tim Böttrich Pascal Bauer Vincent Gröβer Magdalena huber Hartmann Raifer torsten Frech Svenja Nolte theresa Dombrowski franz Cemic Natascha Sommer Robert Ringseis Klaus Eder Karsten Krüger Christopher Weyh Department of Exercise Physiology and Sports therapy Institute of Sports ScienceJustus-Liebig-UniversityGiessen 35394Germany Department of Cardiology and Angiology Justus-Liebig-University GiessenGiessen 35392Germany Institute for Systems Immunology Center for Tumor und ImmunologyMarburg 35032Germany tH Mittelhessen Department of Computer ScienceUniversity of Applied Sciences GiessenGiessen 35390Germany Department of Internal Medicine Universities of Giessen and Marburg Lung Center(UGMLC)Member of the German Center for Lung Research(DZL)Giessen 35394Germany Excellence Cluster Cardio-Pulmonary Institute(CPI) Justus-Liebig UniversityGiessen 35394Germany Institute of Animal Nutrition and Nutrition Physiology Justus-Liebig-University GiessenGiessen 35390Germany

Background:Atherosclerosis forms the pathological basis for the development of cardiovascular *** pathological processes initially develop without clinically relevant symptoms,the identification of early markers in the subclinical stage plays an important role for initiating early *** is evidence that regulatory t cells(tregs)are involved in the development of ***,the present study aimed to identify and investigate associations with tregs and their subsets in a cohort of healthy elderly individuals with and without subclinical atherosclerotic plaques(SAP).In addition,various lifestyle and risk factors,such as cardiorespiratory fitness,were investigated as associated ***:A cross-sectional study was performed in 79 participants(male:n=50;age=63.6±3.7 years;body mass index=24.9±3.1 kg/m2;mean±SD)who had no previous diagnosis of chronic disease and were not taking *** of the carotids to identify SAP,cardiovascular function measurement for vascular assessment and a cardiorespiratory fitness test to determine peak oxygen uptake were ***,tests were conducted to assess blood lipids and determine glucose *** of tregs and their subtypes(resting(rtregs)and effector/memory(mtregs))was performed by 8-chanel flow *** were categorized according to atherosclerotic plaque *** and logistic regression models were used to analyze associations between ***:SAP was detected in a total of 29 *** participants with plaque were older(64.8±3.6 years vs.62.9±3.5 years)and had higher peripheral systolic blood pressure(133.8±14.7 mmHg vs.125.8±10.9 mmHg).the participants with SAP were characterized by a lower percentage of rtregs(28.8%±10.7%vs.34.6%±10.7%)and a higher percentage of mtregs(40.3%±14.7%vs.30.0%±11.9%).Multiple logistic regression identified age(odds ratio(OR)=1.20(95%confidence interval(95%CI):1.011.42))and

关键词： Cardiorespiratory fitness Elderly Regulatory t cells Subclinical atherosclerosis

Generation of brain vascular heterogeneity:recent advances from the perspective of angiogenesis

在线全文

学校读者我要写书评

暂无评论

Neural Regeneration Research 2025年第7期20卷 2013-2014页

作者： Nathanael j.Lee Ryota L.Matsuoka Department of Neurosciences Lerner Research InstituteCleveland ClinicClevelandOHUSA Department of Molecular Medicine Cleveland Clinic Lerner College of MedicineCase Western Reserve UniversityClevelandOHUSA

Heterogeneous proper t i es of vascular endothelial cells in the brain:the brain displays large energy dynamics and consumption,and this high level of metabolic demands is fulfilled by a continuous supply of glucose and oxygen through its vascular *** vasculature consists of highly divergent blood vessel branches,giving rise to a dense network of capillaries that supply blood to all cells across the *** elaborated vascular network is thought to develop via angiogenesis,a process in which new blood vessels grow from pre-existing *** capillaries exhibit organotypic features distinct from other tissues and are formed primarily by two major endothelial cell(EC)types:those that form the semi-permeable blood-brain barrier(BBB)and those that develop highly permeable pores known as fenestrae(Matsuoka et al.,2022).the structural and functional differences between BBB and fenestrated vascular ECs represent a fundamental feature of brain vasculature and form the foundation for both brain function and homeostasis.

关键词： angiogenesis homeostasis network

the mean value concept in mono-linear regression of multi-variables and its application to trace studies in geosciences

在线全文

学校读者我要写书评

暂无评论

Science China Earth Sciences 2007年第12期50卷 1828-1834页

作者： A j t jULL NSF-AMS laboratory University of Arizona

the "mean value concept" in a mono-linear regression of multi-variables is *** applications to reconstruction of the past 90-year salinity of the sea surface water in Xisha Islands and to tracing the past 80 ka paleo-geomagnetic events from the Luochuan loess 10Be record are introduced in detail,which show the significance and the potential of the "mean value concept" in geoscience research.

关键词： mean value concept, linear regression, trace, reconstruction

Effect of surface layer softening from previous electrochemical corrosion on electrochemical cold drawing of Q235 steel bar

在线全文

学校读者我要写书评

暂无评论

journal of Iron and Steel Research International 2022年第5期29卷 819-835页

作者： j.L.Guo t.j.Chen State Key Laboratory of Advanced Processing and Recycling of Nonferrous Metals Lanzhou University of TechnologyLanzhou730050GansuChina

the effects of H_(2)SO_(4)concentration and current in electrochemical corrosion on surface layer softening or plasticizing of Q235 steel bar and their effects on subsequent electrochemical cold drawing(ECD)were *** results indicate that the electrochemical corrosion can soften or plasticize the surface layer of Q235 steel bar and then make the subsequent ECD be conducted more *** softening degree and thickness of the surface layer are continuously enhanced with increasing corrosion rate,i.e.,increasing H_(2)SO_(4)concentration or current,due to the generation of more vacancy clusters in deeper regions of surface *** vacancy clusters then relax dislocations through being absorbed during ECD,and the formation and movement of additional dislocation flux are thereby enhanced,resulting in the further obvious decrease in the drawing *** is also due to the enhanced formation and movement of additional dislocation flux that the dislocation density and thus the hardness of the surface layer are decreased,as well as that the texture structure is *** behaviors are enhanced as the corrosion rate increases.

关键词： Electrochemical corrosion Electrochemical cold drawing Surface layer softening Vacancy Additional dislocation flux

Field-resolved high-order sub-cycle nonlinearities in a terahertz semiconductor laser

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Light(Science & Applications) 2021年第12期10卷 2531-2540页

作者： j.Riepl j.Raab P.Abajyan H.Nong j.R.Freeman L.H.Li E.H.Linfield A.G.Davies A.Wacker t.Albes C.jirauschek C.Lange S.S.Dhillon R.huber Department of Physics University of RegensburgRegensburgGermany Laboratoire de Physique de l’Ecole Normale Supérieure ENSUniversitéPSLCNRSSorbonne UniversitéUniversitéde ParisParisFrance School of Electronic and Electrical Engineering University of LeedsWoodhouse LaneLeedsUK Mathematical Physics and NanoLund Lund UniversityLundSweden Department of Electrical and Computer Engineering Technical University of MunichMunichGermany Department of Physics TU Dortmund UniversityDortmundGermany

the exploitation of ultrafast electron dynamics in quantum cascade lasers(QCLs)holds enormous potential for intense,compact mode-locked terahertz(tHz)sources,squeezed tHz light,frequency mixers,and comb-based metrology *** the important sub-cycle dynamics have been notoriously difficult to access in operational tHz ***,we employ high-field tHz pulses to perform the first ultrafast two-dimensional spectroscopy of a free-running tHz *** incoherent and coherent nonlinearities up to eight-wave mixing are detected below and above the laser *** data not only reveal extremely short gain recovery times of 2 ps at the laser threshold,they also reflect the nonlinear polarization dynamics of the QCL laser transition for the first time,where we quantify the corresponding dephasing times between 0.9 and 1.5 ps with increasing bias currents.A density-matrix approach reproducing the emergence of all nonlinearities and their ultrafast evolution,simultaneously,allows us to map the coherently induced trajectory of the Bloch *** observed high-order multi-wave mixing nonlinearities benefit from resonant enhancement in the absence of absorption losses and bear potential for a number of future applications,ranging from efficient intracavity frequency conversion,mode proliferation to passive mode locking.

关键词： polarization mixer cycle