检索结果-南通市图书馆

Kinemaitcs in spatially flat FLRW spacetimes

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Physics C 2021年第10期 96-105页

作者： Ion I.cot?escu West University of Timi?oara

The kinematics on spatially flat FLRW spacetimes is presented for the first time in local charts with physical coordinates, i.e., the cosmic time and proper Cartesian space coordinates of Painlevé-type. It is shown that there exists a conserved momentum that determines the form of the covariant four-momentum on geodesics in terms of physical coordinates. Moreover, with the help of this conserved momentum, the peculiar momentum can be defined, thus separating the peculiar and recessional motions without ambiguity. It is shown that the energy and peculiar momentum satisfy the mass-shell condition of special relativity while the recessional momentum does not produce energy. In this framework, the measurements of the kinetic quantities along geodesics performed by different observers are analyzed, pointing out an energy loss of the massive particles similar to that producing the photon redshift. The examples of the kinematics on the de Sitter expanding universe and a new Milne-type spacetime are extensively analyzed.

关键词：

Flat limit of the de Sitter QFT in the rest frame vacuum

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Chinese Physics C 2021年第1期45卷 101-112页

作者： Ion I.cot?escu West University of Timi?oara

The problem of the flat limits of the scalar and spinor fields on the de Sitter expanding universe is considered in the traditional adiabatic vacuum and in the new rest frame vacuum we proposed recently, in which the frequencies are separated in the rest frames as in special relativity. It is shown that only in the rest frame vacuum can the Minkowskian flat limit be reached naturally for any momentum, whereas in the adiabatic vacuum, this limit remains undefined in rest frames in which the momentum vanishes. An important role is played by the phases of the fundamental solutions in the rest frame vacuum, which must be regularized to obtain the desired Minkowskian flat limits. This procedure fixes the phases of the scalar mode functions and Dirac spinors, resulting in their definitive expressions derived here. The physical consequence is that, in the rest frame vacuum, the flat limits of the oneparticle operators are simply the corresponding operators of special relativity.

关键词：

Elevated plasma interleukin-8 as a risk factor for mortality in children presenting with cerebral malaria

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Infectious Diseases of Poverty 2023年第1期12卷 47-61页

作者： Jade Royo Bertin Vianou Manfred Accrombessi Elisée Kinkpé Linda Ayédadjou Ida Dossou-Dagba YéléLadipo Maroufou Jules Alao Gwladys I.Bertin Michel cot Farid Boumédiène Sandrine Houzé Jean François Faucher Agnès Aubouy 无 UMR152 PHARMADEV IRDUPSToulouse University35 Chemin Des Maraichers31400 ToulouseFrance Clinical Research Institute of Benin(IRCB) Abomey CalaviBenin Faculty of Infectious and Tropical Diseases Disease Control DepartmentLondon School of Hygiene and Tropical MedicineLondonUK Paediatric Department Calavi HospitalCalaviBenin Paediatric Department Mother and Child University and Hospital Center(CHU-MEL)CotonouBenin UMR261 MERIT IRDParis UniversityParisFrance UMR 1094 EpiMaCT InsermLimoges University HospitalLimoges UniversityLimogesFrance French Malaria Reference Center APHPBichat HospitalParisFrance Parasitology Laboratory APHPBichat-Claude-Bernard HospitalParisFrance Infectious Diseases and Tropical Medicine Department Limoges University HospitalLimogesFrance NeuroCM Group

Background Cerebral malaria(CM)is a neuropathology which remains one of the deadliest forms of malaria among African *** kinetics of the pathophysiological mechanisms leading to neuroinflammation and the death or survival of patients during CM are still poorly *** increasing production of cytokines,chemokines and other actors of the inflammatory and oxidative response by various local actors in response to neuroinflammation plays a major role during CM,participating in both the amplification of the neuroinflammation phenomenon and its *** this study,we aimed to identify risk factors for CM death among specific variables of inflammatory and oxidative responses to improve our understanding of CM *** Children presenting with CM(n=70)due to *** infection were included in southern Benin and divided according to the clinical outcome into 50 children who survived and 20 who *** examination was complemented by fundoscopic examination and extensive blood biochemical analysis associated with molecular diagnosis by multiplex PCR targeting 14 pathogens in the patients'cerebrospinal fluid to rule out *** technology and enzyme immunoassay kits were used to measure 17 plasma and 7 urinary biomarker levels,*** were analysed by univariate analysis using the nonparametric Mann-Whitney U test and Pearson’s Chi2 *** and multivariate analyses were conducted separately for plasma and urinary biomarkers to identify CM mortality risk *** Univariate analysis revealed higher plasma levels of tumour necrosis factor(TNF),interleukin-1beta(IL-1β),IL-10,IL-8,C-X-C motif chemokine ligand 9(CXCL9),granzyme B,and angiopoietin-2 and lower urinary levels of prostanglandine E2 metabolite(PGEM)in children who died compared to those who survived CM(Mann-Whitney U-test,P-values between 0.03 and<0.0001).The multivariate logistic analysis highlighted elevated plasma levels of IL-8 as the m

关键词： Cerebral malaria Children Benin Cytokine Plasma Urine Immunologic marker NeuroCM

Non-traumatic coma in young children in Benin:are viral and bacterial infections gaining ground on cerebral malaria?

在线全文

学校读者我要写书评

暂无评论

Infectious Diseases of Poverty 2022年第2期11卷 1-10页

作者： Josselin Brisset Karl Angendu Baki Laurence Watier Elisee Kinkpe Justine Bailly Linda Ayedadjou Maroufou Jules Alao Ida Dossou-Dagba Gwladys I.Bertin Michel cot Farid Boumediene Daniel Ajzenberg Agnes Aubouy Sandrine Houze Jean-Francois Faucher NeuroCM Group Infectious Diseases and Tropical Medicine Department Limoges University Hospital2 Avenue Martin Luther King87000 LimogesFrance Inserm UMR 1094 IRD U270EpiMaCT-Epidemiology of chronic diseases in tropical zoneInstitute of Epidemiology and Tropical NeurologyOmegaHealthUniv.LimogesCHU LimogesLimogesFrance Center for Research in Epidemiology and Population Health(CESP) INSERM U1018Paris-Saclay UniversityUVSQMontigny-Le-BretonneuxFrance Epidemiology and Modeling of Bacterial Evasion to Antibacterials Unit(EMEA) Institut Pasteur25-28Rue du Dr.Roux75724 Paris Cedex 15France Paediatric Department Calavi HospitalCalaviBenin UMR261 MERIT IRDUniversite de Paris75006 ParisFrance French Malaria Reference Center Hopital BichatAPHPParisFrance Paediatric Department Mother and Child University and Hospital Center(CHU-MEL)CotonouBenin Clinical Research Institute of Benin(IRCB) Abomey CalaviBenin UMR152 PHARMADEV Universite de ToulouseIRDUPSToulouseFrance Parasitology Laboratory Hopital Bichat-Claude-BernardAPHPParisFrance. 不详

Background:While malaria morbidity and mortality have declined since 2000,viral central nervous system infections appear to be an important,underestimated cause of coma in malaria-endemic Eastern *** aimed to describe the etiology of non-traumatic comas in young children in Benin,as well as their management and early outcomes,and to identify factors associated with ***:From March to November 2018,we enrolled all HIV-negative children aged between 2 and 6 years,with a Blantyre Coma Score≤2,in this prospective observational *** were screened for malaria severity signs and assessed using a systematic diagnostic protocol,including blood cultures,malaria diagnostics,and cerebrospinal fluid analysis using multiplex *** determine factors associated with death,univariate and multivariate analyses were ***:From 3244 admissions,84 children were included:malaria was diagnosed in 78,eight of whom had a viral or bacterial *** children had a non-malarial infection or no identified *** mortality rate was 29.8%(25/84),with 20 children dying in the first 24 ***-infected children appeared to have a poorer *** the 76 children who consulted a healthcare professional before admission,only 5 were prescribed adequate antimalarial oral *** of early death were jaundice or increased bilirubin[odd ratio(OR)=8.6;95% confidential interval(CI):2.03-36.1]and lactate>5 mmol/L(OR=5.1;95%CI:1.49-17.30).Antibiotic use before admission(OR=0.1;95%CI:0.02-0.85)and vaccination against yellow fever(OR=0.2,95%CI:0.05-0.79)protected against ***:Infections were found in all children who died,and cerebral malaria was by far the most common cause of non-traumatic *** opportunities to receive early effective antimalarial treatment were *** central nervous system infections must be considered in their *** factors that proved to be protective against early death were unexpected.

关键词： Non-traumatic coma Cerebral malaria Co-infection Central nervous system infection West Africa

Targeting γ-secretase triggers the selective enrichment of oligomeric APP-CTFs in brain extracellular vesicles from Alzheimer cell and mouse models

在线全文

学校读者我要写书评

暂无评论

Translational Neurodegeneration 2019年第1期8卷 433-449页

作者： Inger Lauritzen Anaïs Bécot Alexandre Bourgeois Raphaëlle Pardossi-Piquard Maria-Grazia Biferi Martine Barkats Fréderic Checler Institut de Pharmacologie Moléculaire et Cellulaire CNRS-UMR7275team labeled«Fondation pour la Recherche Médicale»et«Laboratoire d’excellence Distalz»Universitéde Nice-Sophia-AntipolisSophia-AntipolisFrance Institut-Myologie ParisFrance

Background:We recently demonstrated an endolysosomal accumulation of theβ-secretase-derived APP C-terminal fragment(CTF)C99 in brains of Alzheimer disease(AD)mouse ***,we showed that the treatment with theγ-secretase inhibitor(D6)led to further increased endolysosomal APP-CTF levels,but also revealed extracellular APP-CTF-associated *** here hypothesized that this latter staining could reflect extracellular vesicle(EV)-associated APP-CTFs and aimed to characterize theseγ-secretase inhibitor-induced ***:EVs were purified from cell media or mouse brains from vehicle-or D6-treated C99 or APPswedish expressing cells/mice and analyzed for APP-CTFs by *** pharmacological,immunological and genetic approaches(presenilin invalidation and C99 dimerization mutants(GXXXG))were used to characterize vesicle-containing *** APP-CTF localization was determined by ***:Purified EVs from both AD cell or mouse models were enriched in APP-CTFs as compared to EVs from control cells/***,EVs from D6-treated cells not only displayed increased C99 and C99-derived C83 levels but also higher molecular weight(HMW)APP-CTF-immunoreactivities that were hardly detectable in whole cell ***,the intracellular levels of HMW APP-CTFs were amplified by the exosomal inhibitor *** combined pharmacological,immunological and genetic approaches,we established that these HMW APP-CTFs correspond to oligomeric APP-CTFs composed of C99 and/or *** analysis showed that monomers were localized mainly to the trans-Golgi network,whereas oligomers were confined to endosomes and lysosomes,thus providing an anatomical support for the selective recovery of HMW APP-CTFs in *** D6-induced APP-CTF oligomerization and subcellular mislocalization was indeed due toγ-secretase blockade,since it similarly occurred in presenilin-deficient ***,our data proposed t

关键词： Extracellular vesicles C99 APP-CTFs Homo-and hetero-oligomerization Endosomes Lysosomes trans-Golgi network SorLA γ-Secretase inhibition Presenilin knockout Alzheimer’s disease

Carbonaceous residues from biomass gasification as catalysts for biodiesel production

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Natural Gas Chemistry 2012年第3期21卷 246-250页

作者： Rafael Luque Antonio Pineda Juan C. Colmenares Juan M. Campelo Antonio A. Romero Juan Carlos Serrano-Ruiz Luisa F. Cabeza Jaime cot-Gores Departamento de Quimica Organica Universidad de Cardoba Campus de Rabanales Edif icio Marie Curie E-14014 Cardoba Spain Universitat de Lleida GREA lnnovacio Concurrent Lleida Spain Universitat de Lleida GREA lnnovacio Concurrent Lleida Spain

Tars and alkali ashes from biomass gasification processes currently constitute one of the major problems in biomass valorisation, generating clogging of filters and issues related with the purity of syngas production. To date, these waste residues find no useful applications and they are generally disposed upon generation in the gasification process. A detailed analysis of these residues pointed out the presence of high quantities of Ca （〉30 wt%）. TG experiments indicated that a treatment under air at moderate temperatures （400-800 ~C） decomposed the majority of carbon species, while XRD indicated the presence of a crystalline CaO phase. CaO enriched valorized materials turned out to be good heterogeneous catalysts for biodiesel production from vegetable oils, providing moderate to good activities （50%-70% after 12 h） to fatty acid methyl esters in the transesterification of sunflower oil with methanol.

关键词： biomass gasification residues biodiesel catalyst calcium oxide

Two-photon photopolymerization directly initiated by spiropyran photochromic molecules

在线全文

学校读者我要写书评

暂无评论

Light(Advanced Manufacturing) 2023年第1期4卷 12-22页

作者： Dandan Ge Jean Aubard erell Bodinier Safi Jradi Stéphanie Lau-Truong Nordin Felidj Renaud Bachelot Anne-Laure Baudrion Light nanomaterialsnanotechnologies(L2n)LaboratoryCNRS EMR7004Universitéde Technologie de Troyes12 rue Marie Curie10004 Troyes CedexFrance UniversitéParis Cité CNRSITODYSF-75013 ParisFrance

Here,we report the ability of spiropyrans to initiate two-photon polymerization(TPP)for the first time in the *** comparison and synergies between the spiropyran photochromic molecule of interest,namely 6-nitro-BIPS,and well-known photoinitiators of radical photopolymerization have been *** spiropyran(SPy)molecule can initiate TPP in the presence of trifunctional acrylic monomers and create true 3D *** comparison with Irgacure 819,a well-known Type-I photoinitiator,shows that SPy has a comparable capability for *** addition,the combination of SPy with methyl diethanolamine increased the reactivity of both one-and two-photon *** the last section,we discuss which SPy isomer is the active photochromic species capable of generating radicals for initiating two-photon polymerization.

关键词： Spiropyran Direct laser writing Two-photon-photopolymerization Photochromism

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

西班牙语中外教师合作教学模式探索与实践

高教学刊 2023年第21期9卷 8-11页

作者：陈思嘉杨婧媛 JoséManuel Cabello cotán 汕头大学广东汕头515063

该研究以汕头大学西班牙语专业为试验田,于2019—2020秋季学期在大一年级西班牙语精读课程进行中外教合作教学模式的探索与实践。在课程结束后利用问卷调查和访谈的方式收集学生们的反馈与改进意见。结果显示无论教师还是学生都对这种... 详细信息

该研究以汕头大学西班牙语专业为试验田,于2019—2020秋季学期在大一年级西班牙语精读课程进行中外教合作教学模式的探索与实践。在课程结束后利用问卷调查和访谈的方式收集学生们的反馈与改进意见。结果显示无论教师还是学生都对这种教学模式高度认可并且从中获益匪浅。该文将通过介绍合作的具体实施细节和学生们的反馈,为中外教合作教学模式未来的发展提供一定的参考与借鉴。

关键词：西班牙语合作教学中教外教教学实践

Comparison of the Bacterial Microbiota in a Bale of Collected Cardboard Determined by 454 Pyrosequencing and Clone Library

在线全文

学校读者我要写书评

暂无评论

Advances in Microbiology 2014年第12期4卷 754-760页

作者： Valérie Lalande Simon Barnabé Jean-Charles coté Département de Biologie Médicale Université du Québec à Trois-RivièresTrois-RivièresCanada Agriculture and Agri-Food Canada Research and Development CentreSaint-Jean-sur-RichelieuCanada Département de Chimie Biochimie et PhysiqueUniversité du Québec à Trois-RivièresTrois-RivièresCanada

Biofouling, the accumulation of microorganisms, is a major problem in paper mills processing paper and cardboard. This leads to the production of lower quality recycled products. Several studies have focused on the microbial content in the paper mill and the final products. Our aim was to determine the microbial biota in a bale of collected cardboard prior to entering the paper mill. Total genomic DNA was isolated and analyzed using two different methods for comparison purposes: 454 pyrosequencing and clone library. A total of 3268 V6-V8 454 pyrosequencing reads and 322 cloned V6-V8 16S rRNA nucleotide sequences were obtained. Both methods showed the presence of three major bacterial genera: Bacillus, Solibacillus and Paenibacillus, all members of the spore-forming phylum Firmicutes. Pyrosequencing, however, revealed a richer and more diverse bacterial community than clone library. It showed the presence of additional minor Firmicute genera and of a small number of Proteobacteria. The sorting at the recycling plant, the storing, and the processing at the paper mill, the end uses, will all contribute to the bacterial microbiota present in a bale of collected cardboard as revealed here.

关键词： 454 Pyrosequencing Bacterial Microbiota Cardboard Clone Library Paper Mill