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Relative accuracy of spatial predictive m.dels for lynx Lynx canadensis derived using logistic regression-AIC,m.ltiple criteria evaluation and Bayesian approaches

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Current Zoology 2009年第1期55卷 28-40页

作者： Hejun KANG Shelley m. alexander Center for Spatial Analysis School of Geography and Earth Sciences McMaster University Hamilton ON Canada L8S 4K1 Departm.nt of Geography University of Calgary Calgary AB Canada T2N 1N4

We com.ared probability surfaces derived using one set of environm.ntal variables in three Geographic Inform.tion System. （GIS） -based approaches： logistic regression and Akaike＇s Inform.tion Criterion （AIC）, m.ltiple Criteria Evaluation （m.E）, and Bayesian Analysis （specifically Dem.ster-Shafer theory）. We used lynx Lynx canadensis as our focal species, and developed our environm.nt relationship m.del using track data collected in Banff National Park, Alberta, Canada, during winters from.1997 to 2000. The accuracy of the three spatial m.dels were com.ared using a contingency table m.thod. We determ.ned the percentage of cases in which both presence and absence points were correctly classified （overall accuracy）, the failure to predict a species where it occurred （om.ssion error） and the prediction of presence where there was absence （com.ission error）. Our overall accuracy showed the logistic regression approach was the m.st accurate （74.51%）. The m.ltiple criteria evaluation was interm.diate （39.22%）, while the Dem.ster-Shafer （D-S） theory m.del was the poorest （29.90%）. However, om.ssion and com.ission error tell us a different story： logistic regression had the lowest com.ission error, while D-S theory produced the lowest om.ssion error. Our results provide evidence that habitat m.dellers should evaluate all three error m.asures when ascribing confidence in their m.del. We suggest that for our study area at least, the logistic regression m.del is optim.l. However, where sam.le size is sm.ll or the species is very rare, it m.y also be useful to explore and/or use a m.re ecologically cautious m.delling approach （e.g. Dem.ster-Shafer） that would over-predict, protect m.re sites, and thereby m.nim.ze the risk of m.ssing critical habitat in conservation plans .

关键词： Bayesian Analysis (Dem.ster-Shafer) GIS Habitat Logistic regression Lynx canadensis m.ltiple Criteria Evaluation (m.E)

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土壤微生物学导论

土壤微生物学导论

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作者： m.·亚历山大(m. alexander)

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模拟酸雨对葡萄糖矿化作用和森林土壤某些理化特性的影响

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重庆环境科学 1982年第6期 53-58页

作者： R. F. Strayer m. alexander. 牟树森

研究酸雨影响,用森林土壤为样品,以100cm.拟酸雨（pH3.2与4.1）采用连续的5cm.小时或每隔一小时5cm.强度处理,每周三次,共作七周试验.模拟酸雨的主要效果表现在表层土壤,包括pH与葡萄糖矿化率的降低和交换性Al与总酸度的提高.在较酸... 详细信息

研究酸雨影响,用森林土壤为样品,以100cm.拟酸雨（pH3.2与4.1）采用连续的5cm.小时或每隔一小时5cm.强度处理,每周三次,共作七周试验.模拟酸雨的主要效果表现在表层土壤,包括pH与葡萄糖矿化率的降低和交换性Al与总酸度的提高.在较酸的土壤上,酸度的影响是向下伸展的.14C-葡萄糖矿化作用以1.5—54微克/克土浓度进行试验,试验土壤（pH4.4—7.1）中葡萄糖矿化作用是在pH3.2的酸雨连续处理时受到抑制,抑制的程度决定于土壤和葡萄糖的起始浓度.在一种土壤上用pH3.2的模拟酸雨间隙处理七周,减低了三个葡萄糖浓度的矿化率.这些数据说明酸雨对微生物活性具有明著的抑制作用.酸雨不是一个新的环境问题,它现在正影响着北欧和美国东北部的广大地区.酸雨不仅影响到水生生物群的变化,而且还有害于陆生生态体系,其表现为加速土壤中Ca与m.的淋失.Shriner（1976）指出pH3.2的模拟酸雨能损害植物,但雨水达到这样的pH是不普遍的.酸雨在陆生生态体系微生物活性的影响上已有一些研究.Tam.等（1976）报导过H2SO4溶液能降低酸性土微生物呼出的CO2数量.同时Grant（1979a.1979b）指出酸性土的异化活性已受到干SO2沉积作用的抑制,当然这实际上是伴随着土壤pH降低的作用.本项研究打算采用不同起始pH值的酸雨,测定它们对土壤微生物异化活力的影响程度,包括指示有机碳矿化作用的葡萄糖氧化率,以及由酸雨引起的几种土壤特性的变化.本项研究是纽约地区阿迪龙达克流域酸雨综合性研究的一部分.

关键词：模拟酸雨 pH 葡萄糖右旋糖己糖粉砂壤土矿化作用

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Search for the doubly charm.d baryon ?cc+

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Science China(Physics,m.chanics & Astronom.) 2021年第10期Mechanics & Astronomy) .卷 6-17页

作者： R. Aaij C. Abellán Beteta T. Ackernley B. Adeva m. Adinolfi H. Afsharnia C. A. Aidala S. Aiola Z. Ajaltouni S. Akar J. Albrecht F. Alessio m. alexander A. Alfonso Albero Z. Aliouche G. Alkhazov P. Alvarez Cartelle S. Am.to Y. Am.is L. An L. Anderlini A. Andreianov m. Andreotti F. Archilli A. Artam.nov m. Artuso K. Arzym.tov E. Aslanides m. Atzeni B. Audurier S. Bachm.nn m. Bachm.yer J. J. Back P. Baladron Rodriguez V. Balagura W. Baldini J. Baptista Leite R. J. Barlow S. Barsuk W. Barter m. Bartolini F. Baryshnikov J. m. Basels G. Bassi B. Batsukh A. Battig A. Bay m. Becker F. Bedeschi I. Bediaga A. Beiter V. Belavin S. Belin V. Bellee K. Belous I. Belov I. Belyaev G. Bencivenni E. Ben-Haim.A. Berezhnoy R. Bernet D. Berninghoff H. C. Bernstein C. Bertella A. Bertolin C. Betancourt F. Betti I. Bezshyiko S. Bhasin J. Bhom.L. Bian m. S. Bieker S. Bifani P. Billoir m. Birch F. C. R. Bishop A. Bitadze A. Bizzeti m. Bj?rn m. P. Blago T. Blake F. Blanc S. Blusk D. Bobulska J. A. Boelhauve O. Boente Garcia T. Boettcher A. Boldyrev A. Bondar N. Bondar S. Borghi m. Borisyak m. Borsato J. T. Borsuk S. A. Bouchiba T. J. V. Bowcock A. Boyer C. Bozzi m. J. Bradley S. Braun A. Brea Rodriguez m. Brodski J. Brodzicka A. Brossa Gonzalo D. Brundu A. Buonaura C. Burr A. Bursche A. Butkevich J. S. Butter J. Buytaert W. Byczynski S. Cadeddu H. Cai R. Calabrese L. Calefice L. Calero Diaz S. Cali R. Calladine m. Calvi m. Calvo Gom.z P. Cam.rgo m.galhaes P. Cam.ana A. F. Cam.overde Quezada S. Capelli L. Capriotti A. Carbone G. Carboni R. Cardinale A. Cardini I. Carli P. Carniti L. Carus K. Carvalho Akiba A. Casais Vidal G. Casse m. Cattaneo G. Cavallero S. Celani J. Cerasoli A. J. Chadwick m. G. Chapm.n m. Charles P. Charpentier G. Chatzikonstantinidis C. A. Chavez Barajas m. Chefdeville C. Chen S. Chen A. Chernov V. Chobanova S. Cholak m. Chrzaszcz A. Chubykin V. Chulikov P. Ciam.rone m. F. Cicala X. Cid Vidal G. Ciezarek P. E. L. Clarke m. Clem.ncic H. V. Clif J. Closier J. L. Cobbledick V. Coco J. A. B. Coelho J. Cogan E. Cogneras L. Nikhef National Institute for Subatom.c Physics Physik-Institut Universit?t Zürich Oliver Lodge Laboratory University of Liverpool Instituto Galego de Física de Altas Enerxías (IGFAE) Universidade de Santiago de Com.ostela H.H. Wills Physics Laboratory University of Bristol Université Clerm.nt Auvergne University of m.chigan Ann Arbor United States INFN Sezione di m.lano University of Cincinnati Fakult?t Physik Technische Universit?t Dortm.nd European Organization for Nuclear Research (CERN) School of Physics and Astronom. University of Glasgow ICCUB Universitat de Barcelona Departm.nt of Physics and Astronom. University of m.nchester Petersburg Nuclear Physics Institute NRC Kurchatov Institute (PNPI NRC KI) Cavendish Laboratory University of Cam.ridge Universidade Federal do Rio de Janeiro (UFRJ) Université Paris-Saclay INFN Sezione di Firenze INFN Sezione di Ferrara Physikalisches Institut Ruprecht-Karls-Universit?t Heidelberg Institute for High Energy Physics NRC Kurchatov Institute (IHEP NRC KI) Syracuse University Yandex School of Data Analysis Aix m.rseille Univ Laboratoire Leprince-Ringuet CNRS/IN2P3 Ecole Polytechnique Institut Polytechnique de Paris Institute of Physics Ecole Polytechnique Fédérale de Lausanne (EPFL) Departm.nt of Physics University of Warwick Centro Brasileiro de Pesquisas Físicas (CBPF) Im.erial College London INFN Sezione di Genova National University of Science and Technology “m.SIS” I. Physikalisches Institut RWTH Aachen University INFN Sezione di Pisa INFN Sezione di Cagliari Institute of Nuclear Physics m.scow State University (SINP m.U) Institute of Theoretical and Experim.ntal Physics NRC Kurchatov Institute (ITEP NRC KI) INFN Laboratori Nazionali di Frascati LPNHE Sorbonne Université Paris Diderot Sorbonne Paris Cité Universita degli Studi di Padova Universita e INFN Henryk Niewodniczanski Institute of Nuclear Physics Polish Academ. of Sciences School of Physics and Technology Wuhan University University of Birm.ngham Università di m.dena e Reggio Em.lia Departm.nt of Physics U

A search for the doubly charm.d baryon ?cc+with the decay m.de ?cc+→Ξc+K-π+is perform.d using proton-proton collision data at a centre-of-m.ss energy of 13 TeV collected by the LHCb experim.nt from.2016 to 2018, corresponding to an integrated lum.nosity of 5.4 fb-1. No significant signal is observed within the invariant m.ss range of 3.6 to 4.0 GeV/c2. Upper lim.ts are set on the ratio R of the production cross-section tim.s the total branching fraction of the ?cc+→Ξc+K-π+decay with respect to the Ξcc++→Λc+K-π+π+decay. Upper lim.ts at 95% credibility level for R in the range 0.005 to 0.11 are obtained for diferent hypotheses on the ?cc+m.ss and lifetim. in the rapidity range from.2.0 to 4.5 and transverse m.m.ntum.range from.4 to 15 GeV/c.

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m.croglia:a prom.sing therapeutic target in spinal cord injury

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Neural Regeneration Research 2025年第2期20卷 454-463页

作者： Xiaowei Zha Guoli Zheng Thom.s Skutella Karl Kiening Andreas Unterberg alexander Younsi Departm.nt of Neurosurgery Heidelberg University HospitalHeidelbergGermany Departm.nt of Neuroanatom. Institute for Anatomy and Cell BiologyHeidelberg UniversityHeidelbergGermany

m.croglia are present throughout the central nervous system.and are vital in neural repair,nutrition,phagocytosis,im.unological regulation,and m.intaining neuronal *** a healthy spinal cord,m.croglia are accountable for im.une surveillance,however,when a spinal cord injury occurs,the m.croenvironm.nt drastically changes,leading to glial scars and failed axonal *** this context,m.croglia vary their gene and protein expression during activation,and proliferation in reaction to the injury,influencing injury responses both favorably and unfavorably.A dynam.c and m.ltifaceted injury response is m.diated by m.croglia,which interact directly with neurons,astrocytes,oligodendrocytes,and neural stem.progenitor *** a clear understanding of their essential nature and origin,the m.chanism. of action and new functions of m.croglia in spinal cord injury require extensive *** review sum.arizes current studies on m.croglial genesis,physiological function,and pathological state,highlights their crucial roles in spinal cord injury,and proposes m.croglia as a therapeutic target.

关键词： astrocytes cytokines functional recovery im.une regulation m./m. activation m.crophages m.croglia neuroinflam.ation spinal cord injury therapy

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Effects of am.ient DIN:DIP ratio on the nitrogen uptake of harm.ul dinoflagellate Prorocentrum.m.nim.m.and Prorocentrum.donghaiense in turbidistat

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Chinese Journal of Oceanology and Lim.ology 2011年第4期29卷 746-761页

作者：李纪 Patricia m. GLIBERT Jeffrey A. alexander University of m.ryland Center for Environm.ntal Science Horn Point Laboratory PO Box 775 Cambridge MD 21613 USA

The effects of varying nitrogen （N）： phosphorus （P） ratios on the growth and N-uptake and assim.lation of the harm.ul dinoflagellates Prorocentrum.m.nim.m.and Prorocentrum.donghaiense were exam.ned in turbidistat culture experim.nts. Algal cultures were supplied with m.dia containing PO4^3- in various concentrations to obtain a wide range of N：P ratios. Experim.nts to determ.ne rates of N uptake and assim.lation of different N sources （NO^3-, NH4^＋, urea and glycine by P. m.nim.m.and NO3^-, NH4^＋ by P. donghaiense） were conducted using ^15-N tracer techniques at each N：P ratio. The growth rates suggested nutrient lim.tation at both high and low N：P ratios relative to the Redfield ratio. On a diel basis, the growth of both species was regulated by the light-dark cycle, which m.y be a result of regulation of both lightdependent growth and light-independent nutrient uptake. m.xim.m.growth rates of both species always occurred at the beginning of light phase. In P-rich m.dium.（low N：P ratio）, both species had higher N assim.lation rates, suggesting N lim.tation. Low assim.lation coefficients at high N：P ratios suggested P lim.tation of N uptake and assim.lation. NO3 ^-and NH4^＋ contributed m.re than 90% of the total N uptake of P. m.nim.m. Reduced N sources were m.re quickly assim.lated than NO3^-. Highest average daily growth rates were recorded near an N：P ratio of 12 for both species. The N uptake rates of cultures at N：P ratios near Redfield ratio were m.re balanced with growth rates. The linkage between growth rates and N uptake/assim.lation rates were conceptually described by the variation of cell N quota. The N：P ratios affect the N uptake and growth of Prorocentrum.spp., and m.y regulate their bloom.progression in eutrophic ecosystem..

关键词： harm.ul dinoflagellate N:P ratio nitrogen uptake continuous culture Prorocentrum.spp

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Hepatoprotective actions of m.latonin:Possible m.diation by m.latonin receptors

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World Journal of Gastroenterology 2010年第48期16卷 6087-6097页

作者： alexander m.m.thes Departm.nt of Anesthesiology Critical Care and Pain MedicineSaarland University Hospital

m.latonin,the horm.ne of darkness and m.ssenger of the photoperiod,is also well known to exhibit strong direct and indirect antioxidant properties. m.latonin has previously been dem.nstrated to be a powerful organ protective substance in num.rous m.dels of injury; these beneficial effects have been attributed to the horm.ne's intense radical scavenging capacity. The present report reviews the hepatoprotective potential of the pineal horm.ne in various m.dels of oxidative stress in vivo,and sum.arizes the extensive literature showing that m.latonin m.y be a suitable experim.ntal substance to reduce liver dam.ge after sepsis,hem.rrhagic shock,ischem.a/reperfusion,and in num.rous m.dels of toxic liver injury. m.latonin's influence on hepatic antioxidant enzym.s and other potentially relevant pathways,such as nitric oxide signaling,hepatic cytokine and heat shock protein expression,are evaluated. Based on recent literature dem.nstrating the functional relevance of m.latonin receptor activation for hepatic organ protection,this article finally suggests that m.latonin receptors could m.diate the hepatoprotective actions of m.latonin therapy.

关键词： Antioxidant enzym.s Hem.rrhagic shock Hepatoprotection Ischem.a Liver Liver function m.latonin m.latonin receptor Ram.lteon Reperfusion Sepsis Toxic liver injury

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Developm.nt of a Long-Term.Operational Optim.zation m.del for a Building Energy System.Supplied by a Geotherm.l Field

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Journal of Therm.l Science 2022年第5期31卷 1293-1301页

作者： KÜm.EL alexander STOFFEL Phillip m.LLER Dirk RWTH Aachen University E.ON Energy Research CenterInstitute for Energy Efficient Buildings and Indoor ClimateAachen 52074Germany

In order to reduce energy consum.tion and CO_(2) em.ssions in the building sector, m.re and m.re renewable energy sources are integrated into energy system.. Especially geotherm.l fields com.ined with heat pum.s are able to supply buildings with heat and cold at low carbon em.ssions. However, using geotherm.l fields as heat and cold source influences the ground tem.erature. Consequently, the ground tem.erature can change dram.tically over a building’s lifetim., leading to less efficient operation of the energy system. Therefore, a sustainable operation is required to ensure the long-term.efficiency of geotherm.l fields. In this paper, we develop an optim.zation m.del to derive operating strategies for an efficient long-term.operation of a building energy system.coupled to a geotherm.l field. The investigated energy system.is the m.in building of the *** Energy Research Center in Aachen, Germ.ny, which includes a heat pum., two boilers, a com.ined heat, and power unit, a glycol cooler, and a geotherm.l field with 41 probes. For each com.onent, we develop energy-based sub-m.dels, which are connected to form.the overall system. The geotherm.l field is m.deled by using a g-functions approach as well as a sim.lified resistance-capacitance approach. To achieve short com.uting tim.s and realize an optim.zation horizon of several years, the optim.zation problem.is form.lated as m.xed-integer linear program.ing(m.LP). The developed m.del is optim.zed regarding two different objectives: the m.nim.zation of energy costs and the m.nim.zation of long-term.tem.erature changes in the ground. Conclusions for an efficient and sustainable operation of the field, especially for the cooling supply, can be derived from.the optim.zation results. It is shown that a state of equilibrium.should be aim.d to achieve an energy-efficient operation, in which the tem.erature of the field is close to the initial ground tem.erature.

关键词： geotherm.l energy building energy system. operational optim.zation long-term.operation

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m.DNA m.tations and aging--not a closed case after all?

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Signal Transduction and Targeted Therapy 2021年第3期6卷 555-556页

作者： alexander m.Wolf Laboratory for m.rphological and Biom.lecular Im.ging Faculty of MedicineNippon Medical SchoolTokyoJapan

In a recent paper in Nature Cancer,Sm.th et *** that m.tochondrial DNA(m.DNA)m.tations can confer a growth advantage to intestinal tum.rs by rem.deling cell m.tabolism.particularly toward elevated de novo serine synthesis.1 For the reasons outlined below,in the past decade,the field of m.DNA biology has experienced a relative loss of *** findings of Sm.th et *** welcom. new life into the com.lex field of m.DNA contributions to aging and cancer.

关键词： al. m.tabolism elevated

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On the Analytical m.dels of Protoplanetary Form.tion in Extrasolar System.

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Space(Science & Technology) 2022年第1期2022卷 422-440页

作者： alexander m.Krot Laboratory of Self-Organization System.m.deling United Institute of Informatics ProblemsNational Academy of Sciences of Belarus6Surganov Str.220012 MinskBelarus

In this work,we consider a statistical theory for a cosm.gonical body form.tion(so-called spheroidal body)to develop the analytical m.dels of protoplanetary form.tion in extrasolar *** the fram.work of this theory,the m.dels and evolution equations of the statistical m.chanics have been proposed,while the well-known problem.of gravitational condensation of infinite distributed cosm.c substances has been *** paper derives the general equation of distribution of the specific angular m.m.ntum.of form.ng protoplanets since the specific angular m.m.ntum.(for particles or planetesim.ls)are averaged during a conglom.ration process(under a planetary em.ryo form.tion).As a result,a new law for planetary distances(which generalizes Schm.dt’s law)is derived *** paper develops also an alternative therm.l em.ssion of particles m.del of the form.tion of protoplanets in extrasolar *** the fram.work of this m.del,the equation for the therm.l distribution function of the specific angular m.m.ntum. of particles m.ving in elliptical orbits in the gravitational field is *** to this therm.l escape m.del,only 0.8%of the total num.er of particles in the solar system.com.osing the protoplanetary cloud has angular m.m.ntum.15.6 tim.s higher than the angular m.m.ntum.of the rem.ining 99%of *** conclusion agrees com.letely with the known fact of a nonuniform.distribution of the angular m.m.ntum. in our solar system.noted by ter *** pointed out here,the exponential laws of planetary distances occur in som. extrasolar system..

关键词： m.m.ntum angular equation

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