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分析化学 2009年第9期37卷 1333-1336页

作者：郭波莉魏益民 Kelly d.simon 潘家荣魏帅中国农业科学院农产品加工研究所/农业部农产品加工与质量控制重点实验室 Institute of Food Research Norwich

探讨了利用高温热解炉和同位素比率质谱仪(IRMS)联用测定肉品中稳定性氢同位素比率的方法,并利用此方法测定了我国不同地域来源脱脂牛肉、牛尾毛中氢同位素比率。分析了牛组织中氢同位素组成与地域经度、纬度及海拔高度变化的关系,以及... 详细信息

探讨了利用高温热解炉和同位素比率质谱仪(IRMS)联用测定肉品中稳定性氢同位素比率的方法,并利用此方法测定了我国不同地域来源脱脂牛肉、牛尾毛中氢同位素比率。分析了牛组织中氢同位素组成与地域经度、纬度及海拔高度变化的关系,以及稳定性氢同位素用于牛肉产地溯源的可行性。结果表明,不同地域来源牛组织中δ2H值的差异显著,其与当地饮水中氢同位素组成密切相关,而且有随着地理纬度增加而减小的趋势;牛尾毛与牛肉中δ2H值的相关性显著。稳定性氢同位素是用于牛肉产地溯源的一项很有潜力的指标,且牛肉和牛尾毛中的氢同位素组成均可反映牛来源地的信息。

关键词：牛肉产地溯源稳定性氢同位素

Sulforaphane as a Promising Natural Molecule for Cancer Prevention and Treatment

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Current Medical Science 2021年第2期41卷 250-269页

作者： Osama A.Elkashty simon d.Tran McGill Craniofacial Tissue Engineering and Stem Cells Laboratory Faculty of DentistryMcGill UniversityMontreal H3A 0G4Canada department of Oral Pathology Faculty of DentistryMansoura UniversityMansoura 35516Egypt

Tumorigenicity-inhibiting compounds have been identifled in our daily *** example,isothiocyanates(ITCs)found in cruciferous vegetables were reported to have potent cancer=prevention *** best characterized ITC is sulforaphane(SF).SF can simultaneously modulate multiple cellular targets involved in carcinogenesis,including(1)modulating carcinogen-metabolizing enzymes and blocking the action of mutagens;(2)inhibition of cell proliferation and induction of apoptosis;and(3)inhibition of neo-angiogenesis and *** targets cancer stem cells through modulation of nuclear factor kappa B(NF-κB),Sonic hedgehog(SHH),epithelial-mesenchymal transition,and Wnt/βcatenin *** chemotherapy/SF combination was tested in several studies and resulted in favorable *** its favorable toxicological profile,SF is a promising agent in cancer prevention and/or *** this article,we discuss the human metabolism of SF and its effects on cancer prevention,treatment,and targeting cancer stem cells,as well as providing a brief review of recent human clinical trials on SF.

关键词： sulforaphane isothiocyanates cancer chemoprevention antineoplastic agent

Optimal harvesting for a single-species population governed by Gompertz law:Influence of environmental fluctuation and limited harvesting capacity

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International Journal of Biomathematics 2019年第2期12卷 115-142页

作者： P.d.N.Srinivasu simon d.Zawka Sri Sathya Sai University for Human Excellence Navanihala Village Okali PostKamalapur Taluk Gulbarga DistrictKarnataka 585313India department of Mathematics Andhra University Visakhapatnam 530003India department of Mathematics Ar ba Minch University Arba MinchEthiopia

This work presents an optimal harvesting problem associated with a single-species population governed by Gompertz law in a seasonally fluctuating *** influence of environmental fluctuation is accommodated by choosing the coefficients in the differential equation to be periodic functions with the same period and restriction on the harvesting effort is accommodated by considering binding constraints on the control ***,a linear optimal control problem has been considered where the state dynamics is governed by Gompertz equation and the control variable is subject to the binding *** the help of maximum principle and the concept of blocked intervals,an optimal periodic solution has been obtained which is followed by the construe tion of optimal solution using the theory of most rapid *** results of the study are demonstrated through numerical simulations.

关键词： Optimal harvesting Gompertz equation seasonality binding constraint blocked intervals

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大力神Ⅲ点火过压衰减

国外导弹与航天运载器 1990年第3期 33-38页

作者： Elvis d.simon 王亚文

本文介绍了当过压从过压源向上扩展时计算和对比点火过压衰减的新方法。以前对大力神Ⅲ每次飞行和模型点火所确定的衰减关系曲线都不相同。检验过压数据的新方法基于三点。第一,对于相同发射架上的同类运载器,由于发动机或障碍物有差别... 详细信息

本文介绍了当过压从过压源向上扩展时计算和对比点火过压衰减的新方法。以前对大力神Ⅲ每次飞行和模型点火所确定的衰减关系曲线都不相同。检验过压数据的新方法基于三点。第一,对于相同发射架上的同类运载器,由于发动机或障碍物有差别可能使每次试验产生的过压数据大小有所不同,但衰减系数应该相同。第二,运载器、排气羽流和发射架产生的障碍必须考虑。第三,过压从过压源绕障碍物(特别是发射架)扩展到自由场需要有一个过渡距离使过压变成一种自由膨胀波。本文介绍的大力神Ⅲ飞行数据和7.5%模型数据证实了新的衰减模型。

关键词：运载火箭点火排气衰减

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Collembola communities and soil conditions in forest plantations established in an intensively managed agricultural area

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Journal of Forestry Research 2021年第5期32卷 1819-1832页

作者： István Harta Barbara simon Szergej Vinogradov dániel Winkler Institute of Environmental Science Szent István UniversityGödöllőHungary Institute of Methodology Szent István UniversityGödöllőHungary Institute of Wildlife Management and Vertebrate Zoology University of SopronSopronHungary

The challenges of a changing climate have directed greater attention to afforestation,but the effects of afforestation on soil fertility and soil biota have not been fully *** explore changes in the soil conditions in two 20-year-old forest plantations established in formerly intensively fertilized plots of agricultural land,we focused on the current developmental state of the sites that received the most fertilizer and evaluated soil properties and Collembola(springtails)*** oak(Quercus petraea)and black locust(Robinia pseudoacacia)that had been planted in the afforestation sites were assessed for differences between plantations of native and invasive *** adjacent reference associations,including forests and open habitats,were also analyzed and *** showed that the soils in the two afforested sites were similar in their properties and Collembola communities to those of the control cultivated forests,but differed from each other in pH,calcium,phosphorus,and ammonium *** available potassium and phosphorus contents in the soil of the sessile oak plantation were still high,while the soil organic matter content was adequate(SOM>2.0%)in both *** richness of Collembola ranged from 18 in the cultivated arable land to 43 in the relict *** a few species typical for forests(e.g.,Neanura muscorum,Isotomiella minor,Entomobrya muscorum)were detected in the young plantations,while species characteristic of open habitats(e.g.,Protaphorura campata,Lepidocyrtus cyaneus)occurred as *** more individuals and species of Collembola were present in the soil of young plantations than in arable fields,their community diversities were significantly lower compared to the control forest *** community diversity differed significantly also between the two plantation types(with native and non-native tree species).Mean abundance in the afforested sites was about 2.5 times higher than in the cultiv

关键词： Afforestation diversity Fertilizers Soil fauna Soil properties Springtails

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Modified shear cell for characterization of the rheological behavior of particulate networks under compression

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Particuology 2020年第4期18卷 1-9页

作者： simon Hammerich Anthony d.Stickland Benjamin Radel Marco Gleiss Hermann Nirschl Institute of Mechanical Process Engineering and Mechanics Karlsruhe Institute for Technology(KIT)Strasse am Forum 876131 KarlsruheGermany Particulate Fluids Processing Centre Department of Chemical EngineeringThe University of Melbourne3010Australia

Knowledge of the rheological behavior of saturated particulate networks is crucial for every process in which a particulate network is built-up,dewatered,or transported,as in a decanter ***,difficulties arise as to how to characterize the material *** far,no standardized method or measurement device has *** this work,the requirements for a useful device are discussed,followed by the design of a modified shear cell for a Schulze ring shear tester *** and its measurement *** experiments under normal load with different sediments consisting of inorganic and organic particles whose material properties strongly affect the rheological behavior were *** results demonstrate the potential of the modified shear ***,current challenges in characterization are *** characterization possibilities of the developed shear cell are a further step toward understanding the theological behavior of liquid-saturated particulate networks.

关键词： Sediment rheology Saturated particulate network Shear cell Shear compression Rheological behavior

Resistance to ERK1/2 pathway inhibitors;sweet spots,fitness deficits and drug addiction

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Cancer drug Resistance 2019年第2期2卷 365-380页

作者： matthew J.Sale Kathryn Balmanno simon J.Cook Signalling Programme The Babraham InstituteBabraham Research CampusCambridge CB223ATUK

MEK1/2 inhibitors are clinically approved for the treatment of BRAF-mutant melanoma,where they are used in combination with BRAF inhibitors,and are undergoing evaluation in other *** resistance to MEK1/2 inhibitors,including selumetinib(AZd6244/ARRY-142866),can arise through amplification of BRAF^(V600E) or KRAS^(G13d) to reinstate ERK1/2 *** have found that BRAF^(V600E) amplification and selumetinib resistance are fully reversible following drug *** is because resistant cells with BRAF^(V600E) amplification become addicted to selumetinib to maintain a precise level of ERK1/2 signalling(2%-3%of total ERK1/2 active),that is optimal for cell proliferation and *** withdrawal drives ERK1/2 activation outside of this critical“sweet spot”(~20%-30%of ERK1/2 active)resulting in a p57^(KIP2)-dependent G1 cell cycle arrest and senescence or expression of NOXA and cell death with features of autophagy;these terminal responses select against cells with amplified BRAF^(V600E).ERK1/2-dependent p57^(KIP2) expression is required for loss of BRAF^(V600E) amplification and determines the rate of reversal of selumetinib *** of selumetinib-resistant cells with BRAF^(V600E) amplification as tumour xenografts also requires the presence of selumetinib to“clamp”ERK1/2 activity within the sweet ***,BRAF^(V600E) amplification confers a selective disadvantage or“fitness deficit”during drug withdrawal,providing a rationale for intermittent dosing to forestall ***,selumetinib resistance driven by KRAS^(G13d) amplification/upregulation is not *** these cells ERK1/2 reactivation does not inhibit proliferation but drives a ZEB1-dependent epithelial-to-mesenchymal transition that increases cell motility and promotes resistance to traditional chemotherapy *** results reveal that the emergence of drug-addicted,MEKi-resistant cells,and the opportunity this may afford for intermittent dosing

关键词： BRAF CdKN1C/p57^(KIP2) EMT ERK KRAS MEK MEK inhibitor resistance selumetinib

Nest predators, nest-site selection and nest success of the Emei Shan Liocichla(Liocichla omeiensis), a vulnerable babbler endemic to southwestern China

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Chinese Birds 2016年第3期7卷 161-166页

作者： Yiqiang Fu Benping Chen simon d.dowell Zhengwang Zhang Sichuan Institute Key Laboratory for Protecting Endangered Birds in the Southwest Mountains College of Life Sciences Leshan Normal University Laojunshan National Nature Reserve Administration North of England Zoological Society Chester Zoo Ministry of Education Key Laboratory for Biodiversity Science and Ecological Engineering College of Life Sciences Beijing Normal University

Background: The Emei Shan Liocichla(Liocichla omeiensis) is a globally vulnerable babbler, endemic to southwestern China. We investigated its nest predators, nest-site selection and nest success at the Laojunshan National Nature Reserve in Sichuan, China in order to identify the precise nesting-habitat requirements of the species, and to test whether the nest-site-selection cues, preferred by the Emei Shan Liocichla, are positively associated with nest ***: We used infrared cameras to determine nest predators. We compared the microhabitat attributes between nest and random sites, as well as successful and failed nests. We used Binary Logistic Regression to determine the most important variables affecting nest-site selection of the Emei Shan Liocichla. We used the nest survival analysis in Program MARK to estimate daily nest survival rates(dSR). Nest success was calculated using the Mayfield ***: In total 56 nests were found. The dSR for all nests that contained at least one egg was 0.9564 ± 0.0091(95 % CI 0.9346–0.9711)(n = 40), while the total nest success was 27.5 %. We identified four categories of predators in 10 nest predation events, i.e. squirrels(n = 5), snakes(n = 3), raptors(n = 1) and wasps(n = 1). We found that:(1) nest predation was the primary reason for nest failure of the Emei Shan Liocichla,(2) tree cover, bamboo cover, liana abundance and distance to forest edge or gap were the most important variables affecting nest-site selection of this species, and(3) the nest-site-selection variables we measured appeared not to be positively associated with nest ***: Our findings suggest that the Emei Shan Liocichla tended to select nest sites near forest edges or gaps with good concealment and that nest-site selection by this species was nonrandom but not necessarily adaptive. Reducing forest-edge development and protecting bamboo stands should be effective for conservation of this species.

关键词： Nest predator Nest-site selection Nest success Liocichla omeiensis Laojunshan Nature Reserve

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Looking into the future of Nanoelectronics in the diversification Efficient Era

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Science China(Information Sciences) 2016年第6期59卷 6-19页

作者： simon dELEONIBUS Universit′es Grenoble Alpes CEA LETIMINATEC Campus

The linear scaling of CMOS has encountered, since its beginning, many hurdles which request new process modules, driven mainly by the maximization of energy efficiency. Fabrication at the sub 10 nm node level will request Intrinsic Variability approaching to zero. The rapid growth of mobile, multifunctional and autonomous systems is hardly demanding to reach Zero Power consumption. The solutions to integrate Thin Film based devices, architectures and systems in order to face these challenges are described.

关键词： CMOS thin films heterogeneous integration NEMS 3d integration sequential parallel zero intrinsic variability zero power systems