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GnRH在产后奶牛上的应用

动物医学进展 1986年第5期 25-26页

作者： m.d.brown 刘智喜

患围产期障碍的母牛,在产后12—18天给予GnRH,要比未处理的对照母牛发情更早,每次受孕的配种次数更少,空怀的天数更短。在患胎衣不下的母牛中,经GnRH处理的那些较未处理的对照牛,产犊至受孕的间期更短,每次受孕的配种数也更少些。屡配... 详细信息

患围产期障碍的母牛,在产后12—18天给予GnRH,要比未处理的对照母牛发情更早,每次受孕的配种次数更少,空怀的天数更短。在患胎衣不下的母牛中,经GnRH处理的那些较未处理的对照牛,产犊至受孕的间期更短,每次受孕的配种数也更少些。屡配不孕母牛在授精时应用GnRH能够使受孕率提高。有人指出,奶牛繁殖的目标应该是:能在产后3周前开始出现发情周期,到产后4周时子宫已经复旧且无感染,在配上以前的第二个发情周期及其随后的每个发情周期,都显示行为发情,并能够在产后50—85天的第一次配种时受孕。促性腺素释放激素(GnRH),因已证实能够刺激垂体促黄体素(LH)的释放,所以将其列为提高产后奶牛繁殖性能的辅助剂。GnRH应用的主要方面(除治疗卵巢囊肿外)还有发动产后早期(产后10—20天)的卵巢治动,或在授精时给予以提高受孕率。

关键词：产后奶牛胎衣不下胎盘滞留 GnRH 母牛

Wildfire severity alters soil microbial exoenzyme production and fungal abundances in the southern Appalachian mountains

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Pedosphere 2024年第5期34卷 865-878页

作者： megan L.SCHILL Richard BAIRd Shawn P.brown Allison m.VEACH department of Integrative Biology University of Texas at San Antonio Biochemistry Molecular Biology Entomology and Plant Pathology Department Mississippi State University department of Biological Sciences The University of Memphis

Climate change has increased drought frequency and duration that are exacerbated by increased temperatures globally. This effect has, and will continue,to increase fire occurrence across many regions of North America. In the southern Appalachian mountains, wildfires with high burn severity occurred in 2016due to increased drought and human activity. To investigate the effects of burn severity on soil physicochemical properties, microbial extracellular enzyme production, and microbial abundances in a temperate region, surface soils (0–15 cm) were collected from two sites (the Great Smoky mountains National Park in Tennessee and the Nantahala National Forest in North Carolina, USA) spanning lightly, moderately, and severely burned areas, accompanied by adjacent unburned locations that act as controls. The soil samples were collected at three time points between 2017 and 2019 (i.e., 0.5, 1, and 2.5 years post-fire)among burn severity plots. Total hydrolytic enzyme production varied over time, with severe burn plots having significantly lower enzyme production at 2.5years post-fire. Individual enzymes varied among burn severities and across time post-fire. Light burn plots showed greater carbon-specific (β-glucosidase and β-xylosidase) and phosphorus-specific (acid phosphatase) enzyme activities at 0.5 years post-fire, but this effect was transient. At 2.5 years post-fire, theβ-xylosidase and acid phosphatase activities were lower in severe or moderate burn plots relative to the controls. In contrast, the activity of nitrogen-specific enzyme leucyl aminopeptidase was the lowest in severe burn plots at 0.5 years post-fire, but was the lowest in light burn plots at 2.5 years post-fire. The fungi:bacteria ratio declined with burn severity, indicating that fungi are sensitive or less resilient to high burn severity during recovery. These results suggest that wildfires alter trajectories for soil microbial structure and function within a 2.5-year timeframe, which potentially

关键词： 16S rRNA burn severity extracellular enzyme fungi:bacteria ratio internal transcribed spacer microbial structure

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产后奶牛应用GnRH的效果

草食家畜 1986年第2期 51-51页

作者： m.d.brown 王应安

在产后12—18天给患分娩期疾病的母牛注射GnRH时,出现发情的时间较对照牛早,每次受胎的配种次数以及空怀天数也较少。在胎衣滞留的母牛中,用GnRH处理的母牛,产犊间隔较对照牛短。有些人认为,奶牛应在分娩后约3周出现发情周期,产后近4... 详细信息

在产后12—18天给患分娩期疾病的母牛注射GnRH时,出现发情的时间较对照牛早,每次受胎的配种次数以及空怀天数也较少。在胎衣滞留的母牛中,用GnRH处理的母牛,产犊间隔较对照牛短。有些人认为,奶牛应在分娩后约3周出现发情周期,产后近4周子宫复旧,而且无感染。每个发情周期中,都有发情表现,并在产后50—58天首次配种受胎。

关键词： GnRH 受胎率分娩期疾病母牛产犊间隔产犊指数胎衣滞留胎盘滞留

Numerical calculation of Z-scan measurements for nonlinear media with large phase shift

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Optoelectronics Letters 2024年第3期20卷 177-182页

作者： m.d.Zidan A.Allahham department of Physics Atomic Energy Commission of SyriaP.O.Box 6091DamascusSyria

We have reported the characteristics of a Z-scan for the poly(azaneylylidene-acylene)(dAZA) polymer, as nonlinear medium with a large nonlinear phase shift using continuous-wave(CW) laser beam. It has been verified that the Fresnel diffraction model is applicable for analyses of Z-scan measurements with dAZA polymer at high laser power. It was found that Z-scan curves with peak-to-valley features appear as the applied light intensity increases in the case of a large nonlinear phase shift. The Z-scan experiments were carried out using a CW laser to verify the theoretical calculations in the case of a large nonlinear phase shift model. Our results show good agreements between the experimental data and the proposed theoretical models.

关键词： nonlinear phase media

Enhancement of coercivity,permeability,and dielectric properties of Co_(0.2)Zn_(0.3)Ni_(0.5)Eu_(x)Fe_(2-x)O_(4) ferrites for memory and high frequency devices

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Journal of Rare Earths 2024年第6期42卷 1128-1135,I0005页

作者： I.Sardar m.d.Hossain m.S.Sikder m.N.I.Khan m.R.Rahman Physics discipline Khulna UniversityKhulna9208Bangladesh department of Physics Khulna University of Engineering&TechnologyKhulna9203Bangladesh department ofComputer Science and Engineering Northern University of Business&Technology KhulnaKhulna9100Bangladesh material Science division Atomic Energy CentreDhaka1000Bangladesh

Spinel cubic ferrites have huge applications in me mory and high frequency *** the improvement of these modern devices,the magnetic coercivity,permeability,and dielectric properties of a ferrite are the important *** article focuses on improving the magnetic coercivity,magnetic permeability,and dielectric properties of Co_(0.2)Zn_(0.3)Ni_(0.5)Eu_(x)Fe_(2-x)O_(4) ferrites,where x=0.00,0.06,and *** X-ray diffraction(XRd),Fourier transform infrared spectroscopy(FTIR),field emission scanning electron microscopy(FESEm),energy dispersive X-ray(EdX),vibrating sample magnetometer(VSm),and an impedance analyzer were used to characterize the structural,magnetic,and dielectric properties of the *** XRd patterns indicate the formation of spinel cubic structure of the samples with a secondary peak(EuFeO_(3))for Eu doped *** densities and porosities of the samples follow an inverse trend,where the doped samples’lattice parameters are increased with the increment of rare earth Eu *** FTIR analysis also proves the spinel cubic phase of the *** average grain size of the ferrites is obtained via FESEm images,and it is increased from 121 to 198 *** analysis confirms that doping of the Eu content also changes other hysteresis loop properties of Co_(0.2)Zn_(0.3)Ni_(0.5)Eu_(x)Fe_(2-x)O_(4) ***,the coercivity of the Eu doped samples is greater than that of the mother alloy(x=0.00).The EdX study shows that there is no impurity contamination in the *** permeability and dielectric measurements show an improved quality factor of the Eu-doped samples with low magnetic and dielectric *** dependent resistivity and impedance analysis also show the improved *** the observed properties of the samples,all the investigated ferrites might be strong candidates for potential applications in memory devices,magnetic sensors,and high frequency applications.

关键词： Ferrites Raree arths Coercivity Permeability EdX Resistivity

Highly toxic Aβ begets more Aβ

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Neural Regeneration Research 2024年第9期19卷 1871-1872页

作者： merc m.Kemeh Noel d.Lazo Gustaf H.Carlson School of Chemistry and Biochemistry Clark UniversityWorcesterMAUSA

Alzheimer’s disease(Ad)is the most common form of dementia-the 7th leading cause of death *** the tissue level,Ad is characterized by the presence of extracellular amyloid plaques that are comprised primarily of the amyloid-βpeptide(Aβ),and by intraneuronal neurofibrillary tangles composed of *** genetics of early-onset Ad and longitudinal brain-imaging studies of late-onset Ad indicate that extracellular Aβdeposition,in general,precedes neurofibrillary tangle formation in neurons(Hampel et al.,2021;Young-Pearse et al.,2023).

关键词： Aβ tau Alzheimer death

The multi-impurity system in CdSe nanoplatelets:electronic structure and thermodynamic properties

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Communications in Theoretical Physics 2024年第3期76卷 165-173页

作者： d A Baghdasaryan V A Harutynyan E m Kazaryan H A Sarkisyan Russian-Armenian University H Emin 1230051YerevanArmenia Institute of Applied Problems of Physics 25 Nersisyan St0014YerevanArmenia

This paper theoretically studies the impurity states and the effects of impurity concentration and configuration on the optical,electrical,and statistical properties of CdSe nanoplatelets(NPLs).An image charge-based model of electron-impurity interaction is *** charge-carrier energy spectra and corresponding wave functions depending on the impurity number and configuration are *** electron binding energies are calculated for different NPL *** is shown that the image charge-based interaction potential that arises due to the dielectric constants mismatch is much stronger than the interaction potential that does not take such a mismatch into ***,it is demonstrated that the binding energies are increasing with the number of *** calculate the canonical partition function using the energy levels of the electron,which in turn is used to obtain the mean energy,heat capacity,and entropy of the non-interacting electron *** thermodynamic properties of the non-interacting electron gas that depend on the geometric parameters of the NPL,impurity number,configuration,and temperature are studied.

关键词： nanoplateletes thermodynamic properties impurity states

Older Adult Compendium of Physical Activities:Energy costs of human activities in adults aged 60 and older

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Journal of Sport and Health Science 2024年第1期13卷 13-17,F0003页

作者： Erik A.Willis Stephen d.Herrmann mary Hastert Chelsea L.Kracht Tiago V.Barreira John m.Schuna Jr. Zhenghua Cai minghui Quan Scott A.Conger Wendy J.brown Barbara E.Ainsworth Center for Health Promotion and disease Prevention University of North Carolina at Chapel HillChapel HillNC 27599USA Kansas Center for metabolism and Obesity Research The University of Kansas Medical CenterKansas CityKS 66160USA division of Physical Activity and Weight management Department of Internal MedicineUniversity of Kansas Medical CenterKansas CityKS 66160USA Clinical Science division Pennington Biomedical Research CenterBaton RougeLA 70808USA Exercise Science department Syracuse UniversitySyracuseNY 13244USA School of Exercise&Sport Science Oregon State UniversityCorvallisOR 97331USA School of Exercise and Health Shanghai University of SportShanghai 200438China department of Kinesiology Boise State UniversityBoiseID 83725USA School of Human movement and Nutrition Sciences The University of QueenslandSt.LuciaQLD 4072Australia Faculty of Health Sciences and medicine Bond UniversityGold CoastQLD 4229Australia College of Health Solutions Arizona State UniversityPhoenixAZ 85003USA

Purpose:To describe the development of a Compendium for estimating the energy costs of activities in adults>60 years(OA Compendium).methods:Physical activities(PAs)and their metabolic equivalent of task(mET)values were obtained from a systematic search of studies published in 4 sport and exercise databases(Pubmed,Embase,SPORTdiscus(EBSCOhost),and Scopus)and a review of articles included in the 2011 Adult Compendium that measured PA in older *** values were computed as the oxygen cost(VO_(2),mL/kg/min)during PA divided by 2.7 m L/kg/min(mET_(60+))to account for the lower resting metabolic rate in older ***:We identified 68 articles and extracted energy expenditure data on 427 *** these,we derived 99 unique Specific Activity codes with corresponding mET_(60+)values for older *** developed a website to present the OA Compendium mET_(60+)values:https://***:The OA Compendium uses data collected from adults>60 years for more accurate estimation of the energy cost of PAs in older *** is an accessible resource that will allow researchers,educators,and practitioners to find mET_(60+)values for older adults for use in PA research and practice.

关键词： Energy expenditure Exercise mET Older adults

Biomarker bust:meta-analyses reveal unreliability of neuronal extracellular vesicles for diagnosing parkinsonian disorders

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Neural Regeneration Research 2025年第1期20卷 201-202页

作者： Hash brown Taha Leonard davis School of Gerontology University of Southern CaliforniaLos AngelesCAUSA

A range of neurodegenerative disorders,collectively termed parkinsonian disorders,present with a complex array of both motor and non-motor *** in this group are Parkinson’s disease(Pd),dementia with Lewy bodies(dLB),multiple system atrophy(mSA),corticobasal syndrome(CBS),and progressive supranuclear palsy(PSP).These disorders are differentiated neuropathologically by their dominant protein pathologies involvingα-synuclein(α-syn)and/or tau,the types of brain cells affected,such as neurons,oligodendroglia,and astrocytes,and the specific brain regions involved(Tolosa et al.,2021).

关键词： disorders parkin