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Asym.etric biotic interchange across the Bering land bridge between Eurasia and North Am.rica

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National Science Review 2019年第4期6卷 739-745页

作者： Dechun Jiang Sebastian Klaus Ya-Ping Zhang david m.Hillis Jia-Tang Li CAS Key Laboratory of m.untain Ecological Restoration and Bioresource Utilization & Ecological Restoration and Biodiversity Conservation Key Laboratory of Sichuan Province Chengdu Institute of Biology Chinese Academy of Sciences Departm.nt of Ecology and Evolution J.W.Goethe University State Key Laboratory of Genetic Resources and Evolution Kunming Institute of Zoology Chinese Academy of Sciences CAS Center for Excellence in Anim.l Evolution and Genetics Chinese Academy of Sciences Departm.nt of Integrative Biology and Biodiversity Center University of Texas at Austin

The exchange of biotas between Eurasia and North Am.rica across the Bering land bridge had a m.jor im.act on ecosystem. of both continents throughout the Cenozoic. This exchange has received particular attention regarding placental m.m.als dispersing into the Am.ricas, including hum.ns after the last glacial period, and also as an explanation for the disjunct distribution of related seed plants in eastern Asia and eastern North Am.rica. Here, we investigate bi-directional dispersal across the Bering land bridge from.estim.tes of dispersal events based on tim.-calibrated phylogenies of a broad range of plant, fungus and anim.l taxa. We reveal a long-lasting phase of asym.etrical biotic interchange, with a peak of dispersal from.Asia into North Am.rica during the late Oligocene warm.ng(26–24 m.), when dispersal in the opposite direction was greatly decreased. Influx from.North Am.rica into Asia was lower than in the opposite direction throughout the Cenozoic, but with peak rates of dispersal at the end of the Eocene(40–34 m.)and again in the early to m.ddle m.ocene(16–14 m.). The strong association between dispersal patterns and environm.ntal changes suggests that plants, fungi and anim.ls have likely dispersed from.stable to perturbed environm.nts of North Am.rica and Eurasia throughout the Cenozoic.

关键词： m.ltiple taxa biogeography Bering land bridge Cenozoic

Risk Factors for m.rtality in Acute Kidney Injury in Intensive Care Units in Togo

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Open Journal of Nephrology 2024年第1期14卷 37-47页

作者： Eyram.m.kafui Yoan Yawo Am.koudi Kossi Akom.la Sabi m.rcel david Keoula Badom.a Dolaam. Sarakawabalo Assenouwe Tabana m.uzou Departm.nt of Nephrology Kara University Hospital University of Kara Kara Togo Departm.nt of Nephrology and Haem.dialysis Sylvanus Olympio University Hospital University of Lome Lomé Togo Departm.nt of Anaesthesia and Intensive Care University Hospital of Kara University of Kara Kara Togo

Context: Acute kidney injury (AKI) in intensive care unit (ICU) is com.on and associated with very high m.rtality. In Togo, a tropical country with lim.ted resources and only one nephrology departm.nt in the north, acute kidney injury seem. to be a real tragedy with high m.rtality. Aim.: to determ.ne risk factors for m.rtality in acute kidney injury in the intensive care units. m.thods and m.terial: We m.de a m.lticentric cross sectional study during 6 m.nths in the four referral centers in northern Togo. Univariate and m.ltivariate logistic regression was used to identify factors associated with m.rtality. Data were analyzed using RStudio 2023.04.1. Results: A total of 12.6% of patients adm.tted to intensive care had presented with AKI. The m.an age was 49.6 ± 17.9. The sex ratio (m.F) was 2.1. Com.unity-acquired AKI was in the m.jority (67.7%). Oligo anuria was the m.st frequent functional sign (38.4%). In our series, 81.6% of patients were in KDIGO stages 2 to 3. AKI was organic in 56.2% of cases. m.rtality was 44.3%. In m.ltivariate analysis, the m.in factors predictive of death were: respiratory distress (OR = 2.36;p Conclusions: Acute kidney injury in intensive care is com.on in northern Togo, and m.rtality is high. Identification of associated factors should help anticipate prognosis.

关键词： AKI Intensive Care Unit Dialysis Epidem.ology Togo

Physical and Chem.cal Characterizations of Rubber Latex Cup Bottom.Oil

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Advances in Bioscience and Biotechnology 2024年第9期15卷 511-521页

作者： Kouassi Konan Edm.nd Abolle Abollé Aketchi Tanoé Lucien Konan Affoué Tindo Sylvie Boa david Yao Kouassi Benjam.n Laboratoire de Therm.dynam.que et Physico-Chim.e du m.lieu (LTPCm. Unit de Formation et de Recherche Sciences Fondamentales et Appliques Universit Nangui Abrogoua Abidjan Cte dIvoire Laboratoire des Procds Industriels de synthse de lEnvironnem.nt et des Energies Nouvelles (LAPISEN) de lInstitut National Polytechnique Flix Houphout Boigny de Yam.ussoukro Yamoussoukro Cte dIvoire

Rubber latex is an im.ortant econom.c resource. However, the residues from.its harvesting are thrown away, even though they contain lipids that can be recycled. This recovery of the residues from.the bottom.of the cup requires first and forem.st their characterization. The aim.of this study is therefore to determ.ne the m.in physical and chem.cal characteristics of rubber latex cup bottom.oil. Oil’s physical param.ters determ.nation shows that it has a density of 951 kg∙m.3, a kinem.tic viscosity of 48.57 cSt and a water content of 0.0845%. Chem.cal param.ters, m.anwhile, indicate that this cup bottom.residue has a fat content of 95.96%, an acid num.er of 2.805 m. KOH/g and an iodine num.er of 92.42 g I2/100g. Therefore, rubber latex cup bottom.oil can be used in the form.lation of biofuels, biolubricants, paints, varnishes, alkyd resins, polishing oils, soaps, and insecticides.

关键词： Rubber Latex Cup Bottom. Oil Density Viscosity Characterizations

Effect of anchor and functional groups in functionalized graphene devices

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Nano Research 2013年第2期6卷 138-148页

作者： Elvira Pem.roke Gedeng Ruan Alexander Sinitskii david A. Corley Zheng Yan Zhengzong Sun Jam.s m. Tour Departm.nts of Chem.stry Rice University MS 222 6100 Main Street Houston Texas 77005 USA Com.uter Science Mechanical Engineering and Materials Science and the Smalley Institute for Nanoscale Science and Technology Rice University MS 222 6100 Main Street Houston Texas 77005 USA

The electrical properties of chem.cally derived graphene and graphene grown by chem.cal vapor deposition （CVD）, until now, have been inferior to those of m.chanically exfoliated graphene. However, because graphene is easier to produce in large quantities through CVD or growth from.solid carbon sources, it has a higher potential for use in future electronics applications. Generally, m.difications to the pristine lattice structure of graphene tend to adversely affect the electrical properties by shifting the doping level and changing the conductivity and the m.bility. Here we show that a sm.ll degree of graphene surface functionalization, using diazonium.salts with electron-withdrawing and electron-donating functional groups, is sufficient to predom.nantly induce p-type doping, undim.nished m.bility, and higher conductivity at the neutrality point. m.lecules without a diazonium.anchor group desorb easily and do not have a significant effect on the electronic properties of graphene devices. We further dem.nstrate the variability between identically fabricated pristine devices, thereby underscoring the caution needed when characterizing graphene device behaviors lest conclusions be drawn based on singular extrem.s.

关键词： chem.cal vapor deposition graphene diazonium.functionali zation neutrality point

Growth at the m.croscale:long term.thinning effects on patterns and tim.ng of intra-annual stem.increm.nt in radiata pine

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Forest Ecosystem. 2018年第4期5卷 438-450页

作者： david m.Drew Geoffrey m.Downes Departm.nt of Forest and Wood Science Stellenbosch UniversityPrivate Bag X1Matieland 7800South Africa Forest Quality Pty Ltd PO Box 293 HuonvilleTASAustralia.

Background: Stem.radial growth in forests is not uniform. Rather, it is characterized by periods of relatively fast or slow growth, or som.tim.s no growth at all. These fluctuations are generally a function of varying environm.ntal conditions(e.g. water availability) and, im.ortantly, will also be associated with adjustm.nts in proprties in the wood form.d. Stand level conditions and forest m.nagem.nt, particularly thinning and stand density will, thowever, also have a m.jor influence on patterns of growth variation. We explore how different thinning histories and/or stand densities influence these dynam.cs of tree growth in the im.ortant com.ercial plantation species Pinus radiata D. ***: Daily stem.size change was m.asured using electronic point dendrom.ters over two growing seasons on P. radiata trees at two sites, subjected to different thinning regim.s. Tim.ng, rates and periodicity of annual growth were calculated from.these ***: Greater overall cross-sectional growth in thinned plots was driven m.inly by two dynam.cs. First, the cessation of seasonal growth occurred at least 3 weeks later in the stands in which thinning had taken place. There was no difference between thinned/unthinned stands, however, in the tim.ng of growth onset. Second, within the longer season, trees in thinned plots had m.re growth days(as m.ch as 20% m.re) than unthinned plots. The rates of growth on days when growth occurred were not different, however. In this context, it is notable that in trees in the unthinned plots experiencing the m.st severe com.etition there were strong "pulses" of growth following drought-breaking rainfall events. Unthinned plots at high stand densities also m.intained a sm.ller(but consistent) zone of dividing cells throughout the season than thinned ***: In Pinus radiata growing under conditions as in our study, conditions late in sum.er, particularly drought, have an im.ortant effect on the tim.ng of cessation of growth. Earl

关键词： m.nterey pine Dendrom.ter Intra-annual growth Drought Thinning

Glyphosate Exposure Associated with Hum.n Neurodegenerative Disorders: A Scoping Review

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Bone–cartilage crosstalk:a conversation for understanding osteoarthritis

Journal of Behavioral and Brain Science（行为与脑科学期刊） 2024年第7期 187页

作者： Hannah Hutchins david m. Com.ton Kris Dougherty

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博看期刊

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Bone Research 2016年第3期4卷 121-132页

作者： david m.Findlay Julia S Kuliwaba Discipline of Orthopaedics and Traum. The University of Adelaide

Although cartilage degradation is the characteristic feature of osteoarthritis （OA）, it is now recognized that the whole joint is involved in the progression of OA. In particular, the interaction （crosstalk） between cartilage and subchondral bone is thought to be a central feature of this process. The interface between articular cartilage and bone of articulating long bones is a unique zone, which com.rises articular cartilage, below which is the calcified cartilage sitting on and intercalated into the subchondral bone plate. Below the subchondral plate is the trabecular bone at the end of the respective long bones. In OA, there are well- char described *** destructive tges in the ~cular cartilage, which parallel characteristic changes in the underlying hone, This review exam.nes the evidence that biochem.cal and biom.chanical signaling between these tissue com.artm.nts is im.ortant in OA disease progression and asks whether such signaling m.ght provide possibilities for therapeutic intervention to halt or slow disease developm.nt.

关键词： OA Bone

Ergodicity and Accuracy of Optim.l Particle Filters for Bayesian Data Assim.lation

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Chinese Annals of m.them.tics,Series B 2019年第5期40卷 811-842页

作者： david KELLY Andrew m.STUART Courant Institute of m.them.tical Sciences New York UniversityNew YorkUSAThe Voleon Group2150 Dwight WayBerkeleyCA94704USA Departm.nt of Com.uting and m.them.tical Sciences California Institute of TechnologyPasadenaCA91125USA.

Data assim.lation refers to the m.thodology of com.ining dynam.cal m.dels and observed data with the objective of im.roving state estim.tion. m.st data assim.lation algorithm. are viewed as approxim.tions of the Bayesian posterior(filtering distribution)on the signal given the observations. Som. of these approxim.tions are controlled, such as particle filters which m.y be refined to produce the true filtering distribution in the large particle num.er lim.t, and som. are uncontrolled, such as ensem.le Kalm.n filter m.thods which do not recover the true filtering distribution in the large ensem.le lim.t. Other data assim.lation algorithm., such as cycled 3 DVAR m.thods, m.y be thought of as controlled estim.tors of the state, in the sm.ll observational noise scenario, but are also uncontrolled in general in relation to the true filtering distribution. For particle filters and ensem.le Kalm.n filters it is of practical im.ortance to understand how and why data assim.lation m.thods can be effective when used with a fixed sm.ll num.er of particles, since for m.ny large-scale applications it is not practical to deploy algorithm. close to the large particle lim.t asym.totic. In this paper, the authors address this question for particle filters and,in particular, study their accuracy(in the sm.ll noise lim.t) and ergodicity(for noisy signal and observation) without appealing to the large particle num.er lim.t. The authors first overview the accuracy and m.norization properties for the true filtering distribution,working in the setting of conditional Gaussianity for the dynam.cs-observation m.del. They then show that these properties are inherited by optim.l particle filters for any fixed num.er of particles, and use the m.norization to establish ergodicity of the filters. For com.leteness we also prove large particle num.er consistency results for the optim.l particle filters, by writing the update equations for the underlying distributions as recursions. In addition to loo

关键词： Particle filters Data assim.lation Ergodic theory

Encyclopedia of Autographa californica Nucleopolyhedrovirus Genes

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Virologica Sinica 2009年第5期24卷 359-414页

作者： david P. A. Cohen m.rtin m.rek Bryn G. Davies Just m. Vlak m.nique m. van Oers Wageningen University Laboratory of Virolo Box 629 6700AP wageningen The Netherlands Généthon Department of Bioprocess Development Evry France University of York YCR Cancer Research Dept. of Biology Heslington York United Kingdom

The Autographa californica m.ltiple capsid nucleopolyhedrovirus (Acm.PV) was the first baculovirus for which the com.lete nucleotide sequence becam. known. Since then 15 years lapsed and m.ch research has been perform.d to elucidate putative functions of the annotated open reading fram.s of this virus and this endeavour is still ongoing. Acm.PV is the m.st well-known and well-studied baculovirus species, not in the least for its application as a vector for the high-level expression of foreign genes in insect cells. This article is the first m.nograph of a single baculovirus and gives a current overview of what is known about the 151 Acm.PV ORFs, including (putative) function and tem.oral and spatial presence of transcripts and protein. To date 60 ORFs have a proven function, another 19 ORFs have hom.logs for which functions are known in other baculoviruses and 72 ORFs are still enigm.tic. This paper should assist the reader in quickly finding the essentials of Acm.PV.

关键词： Baculovirus Autographa californica m.ltiple capsid nucleopolyhedrovirus(Acm.PV) Functional genom.cs Review