检索结果-南通市图书馆

Experimental measurements of gamma-photon production and estimation of electron/positron production on the PETAl laser facility

引用

Matter and Radiation at Extremes 2024年第5期9卷 32-47页

作者： F.Brun l.Ribotte G.Boutoux X.Davoine P.E.Masson-laborde Y.Sentoku n.Iwata n.Blanchot D.Batani I.lantuéjoul l.lecherbourg B.Rosse C.Rousseaux B.Vauzour D.Raffestin E.D’Humières X.Ribeyre Centre lasers Intenses et Applications UMR 5107Universitéde Bordeaux-CNRS-CEA33405 TalenceFrance CEA DAMCESTAF-33116 Le BarpFrance CEA DAMDIFF-91297 ArpajonFrance CEA LMCEUniversitéParis-Saclay91680 Bruyères-le-ChâtelFrance Institute of laser Engineering Osaka University2-6 YamadaokaSuitaOsaka 565-0871Japan

This article reports the first measurements of high-energy photons produced with the high-intensity PETawatt Aquitaine laser(PETAl)*** experiments were performed during the commissioning of the *** laser had an energy of about 400 J,an intensity of 8×10^(18)W cm^(−2),and a pulse duration of 660 fs(FWHM).It was shot at a 2 mm-thick solid tungsten *** high-energy photons were produced mainly from the bremsstrahlung process for relativistic electrons accelerated inside a plasma generated on the front side of the *** paper reports measurements of electrons,protons and *** electrons up to35 MeV with a few-MeV temperature were recorded by a spectrometer,called SESAME(SpectreÉlectronS Angulaire MoyenneÉnergie).K-and l-shells were clearly detected by a photon spectrometer called SPECTIX(Spectromètre PetalàCristal en TransmIssion pour le rayonnnement X).High-energy photons were diagnosed by CRACC-X(Cassette de RAdiographie Centre Chambre-rayonnement X),a bremsstrahlung *** cannon analysis is strongly dependent on the hypothesis adopted for the spectral *** shapes can exhibit similar reproductions of the experimental *** eliminate dependence on the shape hypothesis and to facilitate analysis of the data,simulations of the interaction were *** model the mechanisms involved,a simulation chain including hydrodynamic,particle-in-cell,and Monte Carlo simulations was *** simulations model the preplasma generated at the front of the target by the PETAl laser prepulse,the acceleration of electrons inside the plasma,the generation of MeV-range photons from these electrons,and the response of the detector impacted by the energetic photon *** this work enabled reproduction of the experimental *** high-energy photons produced have a large emission angle and an exponential distribution *** addition to the analysis of the photon spectra,positron production was also ***,if high

关键词： process. positron hypothesis

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

On the functions of astrocyte-mediated neuronal slow inward currents

引用

neural Regeneration Research 2024年第12期19卷 2602-2612页

作者： Balázs Pál Department of Physiology Faculty of MedicineUniversity of DebrecenDebrecenHungary

Slow inward currents are known as neuronal excitatory currents mediated by glutamate release and activation of neuronal extra synaptic n-met hyl-D-aspartate receptors with the contribution of *** events are significantly slower than the excitatory postsynaptic *** of slow inward currents are determined by seve ral factors including the mechanisms of astrocytic activation and glutamate release,as well as the diffusion pathways from the release site towards the extra synaptic recepto *** are stimulated by neuronal network activity,which in turn excite neurons,forming an astrocyte-neuron feedback *** as a consequence of brain edema,astrocytic swelling can also induce slow inward currents under pathological *** is a growing body of evidence on the roles of slow inward currents on a single neuron or local network *** events often occur in synchro ny on neurons located in the same astrocytic *** synchronization of neuronal excitability,slow inward currents also set synaptic strength via eliciting timing-dependent synaptic *** addition,slow inward currents are also subject to non-synaptic plasticity triggered by long-la sting stimulation of the excitatory *** note,there might be important regionspecific differences in the roles and actions triggering slow inward *** greater networks,the pathophysiological roles of slow inward currents can be better understood than physiological *** inward currents are identified in the pathophysiological background of autism,as slow inward currents drive early hypersynchrony of the neural *** inward currents are significant contributors to paroxysmal depolarizational shifts/interictal *** events are related to epilepsy,but also found in Alzheimer's disease,Parkinson's disease,and stroke,leading to the decline of cognitive *** with features overlapping with slow inward currents(excitatory,n-methyl-Dasp

关键词： astrocyte cortical spreading depolarization gliotransmission glutamate neural synchronization nMDA receptor paroxysmal depolarizational shift slow inward current

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

The importance of post-COVID condition phenotypes characterization to decipher the mechanisms underlying this post-viral syndrome

引用

World Journal of Pediatrics 2024年第6期20卷 633-634页

作者： Jon Izquierdo-Pujol Sara Moron-lopez IrsiCaixa and Institute for Health Science Research Germans Trias i Pujol(IGTP) Can Ruti CampusBadalonaSpain Biomedicine doctoral programme Faculty of BiologyUniversity of BarcelonaBarcelonaSpain CIBERInFEC MadridSpain

The coronavirus disease-19(COVID-19)outbreak,caused by the severe acute respiratory syndrome coronavirus 2(SARS-CoV-2),was declared a global pandemic in March *** has affected over 700 million people worldwide and resulted in almost 7 million deaths,equating to a 1%mortality *** present,the majority of COVID-19 cases are either asymptomatic or mild,typically resolving within two ***,between 1%and 10%of COVID-19 survivors do not fully recover and experience a post-viral syndrome referred to as"long COVID","post-acute COVID-19 syndrome"(PASC),or"post-COVID condition"(PCC).This post-viral syndrome affects both adult and pediatric ***,most of the studies published to date evaluate the adult population,leaving a gap in our understanding of its impact on children and adolescents.

关键词： acute mortality respiratory

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

On calculating glacial isostatic adjustment

引用

Geodesy and Geodynamics 2024年第5期15卷 441-452页

作者： l.M.Cathles Cornell University IthacaNY 14853USA

Modeling the earth's fluid and elastic response to the melting of the glaciers of the last ice age is the most direct way to infer the earth's radial viscosity ***,we compare two methods for calculating the viscoelastic response to surface *** one,the elastic equation of motion is converted to a viscoelastic equation using the Correspondence *** the other,elastic deformation is added to the viscous flow as isostatic adjustment *** two modeling methods predict adjustment histories that are different enough to potentially impact the interpretation of the observed glacial isostatic adjustment(GIA).The differences arise from buoyancy and whether fluid displacements are subjected to hydrostatic *** methods agree if they use the same equations and boundary *** origin of the differences is determined by varying the boundary conditions and pre-stress application.

关键词： Glacial isostatic adjustment Viscoelastic normal modes Hydrostatic pre-stress Elastic buoyancy Correspondence principle

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Effect of radiative loss mechanisms on FIR thermometric parameters of nd^(3+)-doped lithium tellurite glasses

引用

Journal of Rare Earths 2024年第7期42卷 1250-1257,I0002页

作者： C.Y.Morassuti A.P.l Silva l.A.O.nunes S.M.lima l.H.C.Andrade Optical and Photothermal Spectroscopy Group(GEOF) Center for Studies in Natural Resources(CERNA)State University of Mato Grosso do Sul(UEMS)C.P.351DouradosMSBrazil Renato Archer Information Technology Center Dom Pedro I Highway(SP-65)Km 1436-Chácaras Campos dos AmaraisCampinasSPBrazil Institute of Physics of São Carlos University of São PauloSão CarlosSPBrazil

nd^(3+)-doped tellurite glasses are promising materials for thermometers based on the fluorescence intensity ratio(FIR)***,at high nd^(3+)concentrations,energy transfer(ET)processes such as optical reabsorption and cross-relaxation can affect the nd^(3+)emission,which has been little explored in the ***,the present work investigated the use of nd^(3+)-doped tellurite glass(samples doped with nd^(3+)at 0.2 mol%,0.5 mol%,2.0 mol%,and 4.0 mol%)in fluorescence thermometers,in the temperature range from 299 to 371 *** results indicate a strong dependence of the FIR parameters on the nd^(3+)concentration,due to changes in the emission band profiles caused by optical reabsorption of the nd^(3+)emissions and cross-relaxation processes.A decrease of the relative sensitivity of the ratio^(4)F_(5/2)→^(4)I_(9/2)/^(4)F_(3/2)→^(4)I_(9/2)is observed for samples doped with higher amounts of nd^(3+).The maximum relative sensitivity at 299 K is 3.00%/K,which is the highest value among the reported nd^(3+)ions.

关键词： nd^(3+)-doped tellurite glass Fluorescence intensity ratio Optical thermometry Judd-Ofelt Rare earths

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Polyelectrolyte Complexes between Hyperbranched and linear Polysaccharides: Fucoidan/Chitosan

引用

Chinese Journal of Polymer Science 2024年第4期42卷 468-479页

作者： Ekaterina R.Gasilova Daria n.Poshina Aleksandra O.Sitnikova natalia n.Saprykina Yury A.Skorik Institute of Macromolecular Compounds of the Russian Academy of Sciences Bolshoi VO 31St.Petersburg199004Russian Federation

Polyelectrolyte complexes(PECs)of hyperbranched(HB)and linear polysaccharides are promising as more effective encapsulation agents compared to PECs formed by linear *** investigated the PECs between the HB anionic polysaccharide fucoidan(FUC)and the cationic linear polysaccharide chitosan(CS).The FUC had a molecular weight(MW)of 30×*** PECs were prepared in three solvents(water,0.01 and 0.1 mol/l acetic acid)with CS of MW of 15,110 and 170 kDa,and deacetylation degrees(DDA)of 70%and 97%.The structures of the PECs and the initial FUC were investigated by multi-angle static and dynamic light *** the FUC contained 18 wt%of—OSO3 groups and 5 wt%of uronic acid units,it was a“strong-weak”copolyanion,so the HB macromolecules of the FUC formed nanogel particles in 0.1 mol/l AcOH and open branched structures in water,as confirmed by the Kratky *** mixing the solutions of original components,the PEC structures underwent an equilibration period,the duration of which increased with the MW of *** the charge stoichiometry was approached,the PECs shrank;the fractal dimension approached unity,indicating the side-by-side packing of adjacent FUC branches with the help of *** aggregation in the vicinity of the charge compensation was hardly observed,as it occurred in a very narrow *** PEC content at theζ-potential inversion depended on solvents’pH and the DDA of *** the extreme case of core-shell PECs in 0.1 mol/l AcOH,obtained by mixing FUC nanogels with the solutions of high MW CS of 97%DDA,the protruding tails of CS formed a positively charged shell in the whole range of FUC content(10 wt%nning electron microscopy and atomic force microscopy images of dried samples were discussed in relation to the light scattering results.

关键词： Polyelectrolyte complexes Chitosan Hyperbranched fucoidan light scattering

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Imprints of a gravitational wave through the weak field deflection of photons

引用

Chinese Physics C 2024年第8期48卷 240-245页

作者： Reggie C.Pantig Ali Övgün Physics Department Mapúa University658 Muralla St.IntramurosManila 1002Philippines Physics Department Eastern Mediterranean UniversityFamagusta99628 North Cyprusvia Mersin 10Turkiye

In this study,we investigate the novel phenomenon of gravitational lensing experienced by gravitational waves traveling past a Schwarzschild black hole perturbed by a specific,first-order,polar gravitational *** apply the Gauss-Bonnet theorem,finding a topological contribution to the deflection of light rays passing near the black *** demonstrate that the deflection angle can be determined by analyzing a region entirely outside the path of the light ray,leading to a calculation based solely on the parameters of the perturbing wave(legendre polynomial order,l;frequency,σ).This approach offers a unique perspective on gravitational lensing and expands our understanding of black hole interactions with gravitational waves.

关键词： supermassive black holes gravitational waves chaos weak deflection angle Gauss-Bonnet theorem

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Generation of polarized electron beams through self-injection in the interaction of a laser with a pre-polarized plasma

引用

High Power laser Science and Engineering 2024年第3期12卷 62-68页

作者： l.R.Yin X.F.li Y.J.Gu n.Cao Q.Kong M.Büscher S.M.Weng M.Chen Z.M.Sheng Key laboratory of nuclear Physics and Ion-beam Application(MoE) Institute of Modern PhysicsDepartment of Nuclear Science and TechnologyFudan UniversityShanghaiChina State Key laboratory of High Field laser Physics Shanghai Institute of Optics and Fine MechanicsChinese Academy of SciencesShanghaiChina SAnKEn(Institute of Scientific and Industrial Research) Osaka UniversityOsakaJapan Sichuan Research Institute Shanghai Jiao Tong UniversityChengduChina Peter Grünberg Institut(PGI-6) Forschungszentrum JülichJülichGermany Institut für laser-und Plasmaphysik Heinrich-Heine-Universität DüsseldorfDüsseldorfGermany Key laboratory for laser Plasmas(MoE) School of Physics and AstronomyShanghai Jiao Tong UniversityShanghaiChina Collaborative Innovation Center of IFSA Shanghai Jiao Tong UniversityShanghaiChina Tsung-Dao lee Institute Shanghai Jiao Tong UniversityShanghaiChina

Polarized electron beam production via laser wakefield acceleration in pre-polarized plasma is investigated by particlein-cell *** evolution of the electron beam polarization is studied based on the Thomas±Bargmann±Michel±Telegdi equation for the transverse and longitudinal self-injection,and the depolarization process is found to be influenced by the injection *** the case of transverse self-injection,as found typically in the bubble regime,the spin precession of the accelerated electrons is mainly influenced by the ***,in the case of longitudinal injection in the quasi-1D regime(for example,*** et al.,***.110,135002(2013)),the direction of electron spin oscillates in the laser *** the electrons move around the laser axis,the net influence of the laser field is nearly zero and the contribution of the wakefield can be ***,an ultra-short electron beam with polarization of 99%can be obtained using longitudinal self-injection.

关键词： laser wakefield acceleration longitudinal self-injection particle-in-cell simulation polarized electron beam

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Intermediate Hip Arthroplasty in Gabon: Blood loss and Risk Factor for Transfusion

引用

Open Journal of Anesthesiology 2024年第4期14卷 109-117页

作者： Ghislain Edjo nkilly Pascal Christian nze Obiang Raphael Okoue Ondo Arthur Matsanga Stéphane oliveira léandre nguiabanda Jean-Marcel Mandji-lawson Department of Anaesthesia and Intensive Care Omar Bongo Ondimba Army Training Hospital (HIAOBO) Libreville Gabon Department of Anaesthesia and Intensive Care Jeanne Ebori Fondation Libreville Gabon Department of Anaesthesia and Intensive Care Owendo University Hospital (CHUO) Libreville Gabon Department of Anaesthesia and Intensive Care Akanda Army Training Hospital Libreville Gabon Orthopedic Surgery Service Omar Bongo Ondimba Army Training Hospital (HIAOBO) Libreville Gabon

Background: Hip arthroplasty is a surgery with a high risk of bleeding. The main objective of this study was to research risk factors for bleeding and transfusion in patients undergoing hip hemiarthroplasty in Gabon. Method: It was a retrospective, monocentric, descriptive and analytical study carried out from June 2011 to June 2021 at the Omar Bongo Ondimba army training hospital. The variables studied were demographic characteristics, biological variables, transfusion and intraoperative data. The primary outcome was intraoperative transfusion. A univariate and multivariate analysis was conducted to identify the factors associated with the occurrence of a transfusion. Results: Of the 97 patients included, the average age was 74.2 years ± 10, male predominance was 73.2%, the average ASA score was 1.9 ± 0.5, and transfusion incidence was 38.1%. The average number of RBCs transfused was 1.2 ± 0.6. Tranexamic acid was used in 11.3% of patients. The average bleeding was 450 ± 453 ml. Preoperative anemia was predictor of transfusion to be significant. Conclusion: The incidence of transfusion is law compared to total hip arthroplasty. The implementation of a patient blood management protocol is difficult given the urgency of bone repair. However, a better use of tranexamic acid could reduce this transfusion incidence.

关键词： Hip Arthroplasty Risk Factors Patients Hemiarthroplasty Gabon

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Some Mean Convergence Theorems for the Maximum of normed Double Sums of Banach Space Valued Random Elements

引用

Acta Mathematica Sinica,English Series 2024年第7期40卷 1727-1740页

作者： Andrew ROSAlSKY le Van THAnH nguyen Thi THUY Department of Statistics University of FloridaGainesvilleFL 32611-8545USA Department of Mathematics Vinh UniversityVinhNghe AnViet Nam High School for Gifted Students Vinh UniversityVinhNghe AnViet Nam

In this correspondence,we establish mean convergence theorems for the maximum of normed double sums of Banach space valued random *** of the results pertain to random elements which are *** expand and improve a number of particular cases in the literature on mean convergence of random elements in Banach *** of the main contributions of the paper is to simplify and improve a recent result of li,Presnell,and Rosalsky[Journal of Mathematical Inequalities,16,117–126(2022)].A new maximal inequality for double sums of M-dependent random elements is proved which may be of independent *** sharpness of the results is illustrated by four examples.

关键词： Double sum mean convergence Rademacher type p Banach space Banach space valued random element M-dependent random elements

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：