检索结果-南通市图书馆

Small mammal community composition impacts bank vole (Clethrionomys glareolus) population dynamics and associated seroprevalence of Puumala orthohantavirus

在线全文

学校读者我要写书评

暂无评论

Integrative Zoology 2024年第1期19卷 52-65页

作者： Felicitas Maria BUJNOCH Daniela REIL Stephan DREWES Ulrike MROSENFELD Rainer g.ULRICH Jens JACOB christian IMHOLT Julius Kühn-Institute Federal Research Centre for Cultivated PlantsInstitute for Epidemiology and Pathogen DiagnosticsRodent ResearchMünsterGermany University of Münster Institute for Evolution and BiodiversityMünsterGermany Friedrich-Loeffler-Institut Federal Research Institute for Animal HealthInstitute of Novel and Emerging Infectious DiseasesGreifswald-Insel RiemsGermany

Rodents are important reservoirs for zoonotic pathogens that cause diseases in humans.Biodiversity is hypoth-esized to be closely related to pathogen prevalence through multiple direct and indirect pathways.For example,the presence of non-host species can reduce contact rates of the main reservoir host and thus reduce the risk of transmission(“dilution effect”).In addition,an overlap in ecological niches between two species could lead to increased interspecific competition,potentially limiting host densities and reducing density-dependent pathogen transmission processes.In this study,we investigated the relative impact of population-level regulation of direct and indirect drivers of the prevalence of Puumala orthohantavirus(PUUV)in bank voles(Clethrionomys glareolus)during years with high abundance.We compiled data on small mammal community composition from four regions in germany between 2010 and 2013.Structural equation modeling revealed a strong seasonality in PUUV control mechanisms in bank voles.The abundance of shrews tended to have a negative relationship with host abundance,and host abundance positively influenced PUUV seroprevalence,while at the same time increasing the abundance of competing non-hosts like the wood mouse(Apodemus sylvaticus)and the yellow-neckedfield mouse(Apodemusflavicollis)were associated with reduced PUUV seroprevalence in the host.These results indicate that for PUUV in bank voles,dilution is associated with increased interspecific competition.Anthropogenic pressures leading to the decline of Apodemus spp.in a specific habitat could lead to the amplification of mechanisms promoting PUUV transmission within the host populations.

关键词： bank vole biodiversity Puumala orthohantavirus small mammals

gust response of an elasto-flexible morphing wing using fluid–structure interaction simulations

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 Journal of Aeronautics 2024年第2期37卷 45-57页

作者： Jonathan PFLÜgER christian BREITSAMTER Department of Mechanical Engineering Technical University of MunichGarching 85748Germany

Small and micro unmanned aircraft are the focus of scientific interest due to their wide range of applications.They often operate in a highly unstable flight environment where the application of new morphing wing technologies offers the opportunity to improve flight characteristics.The investigated concept comprises port and starboard adjustable wings,and an adaptive elastoflexible membrane serves as the lifting surface.The focus is on the benefits of the deforming membrane during the impact of a one-minus-cosine type gust.At a low Reynolds number of Re=264000,the morphing wing model is investigated numerically by unsteady fluid-structure interaction simulations.First,the numerical results are validated by experimental data from force and moment,flow field,and deformation measurements.Second,with the rigid wing as the baseline,the flexible case is investigated,focusing on the advantages of the elastic membrane.For all configurations studied,the maximum amplitude of the lift coefficient under gust load shows good agreement between the experimental and numerical results.During the decay of the gust,they differ more the higher the aspect ratio of the wing.When considering the flow field,the main differences are due to the separation behavior on the upper side of the wing.The flow reattaches earlier in the experiments than in the simulations,which explains the higher lift values observed in the former.Only at one intermediate configuration does the lift amplitude of the rigid configuration exceeds that of the flexible by about 12%,with the elastic membrane resulting in a smaller and more uniform peak load,which is also evident in the wing loading and hence in the root bending moment.

关键词： Membrane wing Morphing wing Flexible wing surface Computational fluid dynam-ics Fluid-structure interaction Unsteady inflow condition gust response

Diabetes and pulmonary infection:how hyperglycaemia shapes the immune system

在线全文

学校读者我要写书评

暂无评论

Signal Transduction and Targeted Therapy 2024年第4期9卷 1245-1246页

作者： christian Herder Michael Roden Nicolas Venteclef Institute for Clinical Diabetology German Diabetes CenterLeibniz Center for Diabetes Research at Heinrich Heine University Düsseldorf40225DüsseldorfGermany german Center for Diabetes Research(DZD) Partner Düsseldorf85764München-NeuherbergGermany Department of Endocrinology and Diabetology Medical Faculty and University Hospital DüsseldorfHeinrich Heine University Düsseldorf40225DüsseldorfGermany Institut Necker-Enfants Malades(INEM) UniversitéParis CitéINSERM UMR-S1151CNRS UMR-S8253ParisFrance

In a recent study published in Nature,Nobs and colleagues aimed to identify novel mechanisms that may explain why diabetes is associated with an increased susceptibility to viral respiratory infections.Their analyses revealed a central role of lung dendritic cells(DC)which exhibited several functional defects induced by hyperglycaemia and consequently result in impaired antiviral immune responses.

关键词： impaired lung respiratory

Clustering of voltage-gated ion channels as an evolutionary trigger of myelin formation

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Neural Regeneration Research 2024年第8期19卷 1631-1632页

作者： Henrike Ohm Simone Rey christian Klambt Institut fur Neuro-und Verhaltensbiologie MunsterGermany

Neurons carry apical dendrites that perceive information and a basal axon that transmits the computed information towards its to rgets.The axon originates at the axon hillock which is followed by the axon initial segment.Here,action potentials are initiated that are based on millisecond long openings of specific voltagegated sodium and potassium channels that are conserved in all parahoxozoa(Placozoa,Cnidaria,Bilateria)(Li et al.,2015).

关键词： initiated carry potassium

Ray tracing particle image velocimetry-Challenges in the application to a packed bed

在线全文

学校读者我要写书评

暂无评论

Particuology 2024年第1期84卷 194-208页

作者： Christin Velten Mirko Ebert christian Lessig Katharina Zahringer Lehrstuhl für Strömungsmechanik und Strömungstechnik Otto-von-Guericke-Universität Magdeburg39106MagdeburgGermany Institut für Simulation und graphik Otto-von-Guericke-Universität Magdeburg39106MagdeburgGermany

Ray tracing Particle Image Velocimetry(RT-PIV)is an optical technique for high resolution velocity measurements in challenging optical systems,such as transparent packed beds,that uses ray tracing to correct for distortions introduced by transparent geometries in the light paths.The ray tracing based correction is a post processing step applied to the raw PIV particle images before classical PIV evaluation.In this study,RT-PIV is performed in the top layer of a body centred cubic(bcc)sphere packing with gaseous flow,where optical access is obtained by the use of transparent N-BK7 glass balls with a diameter of d=40 mm.RT-PIV introduces new experimental and numerical challenges,for example a limited field of view,illumination difficulties,a very large required depth of field and high sensitivity to geometric parameters used in the ray tracing correction.These challenges and their implications are the main scope and discussed in the present work.Further,the validation of the ray tracing reconstruction step is presented and examples for the obtained corrected vector fields in a packed bed are given.The results show the strength of the method in reconstructing velocity fields behind transparent spheres that would not have been accessible by optical measurement techniques without the ray tracing correction.

关键词： Ray tracing particle image velocimetry(RT-PIV) Transparent spherical particles Packed bed Distortion correction gas flow

Medical management of urolithiasis: great efforts and limited progress

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Asian Journal of Urology 2024年第2期11卷 149-155页

作者： Victoria Jahrreiss christian Seitz Fahad Quhal Department of Urology Comprehensive Cancer CenterMedical University of ViennaViennaAustria Department of Urology King Fahad Specialist HospitalDammamSaudi Arabia

Objective:To provide a comprehensive review on the existing literature on medical management of urolithiasis.Methods:A thorough literature review was performed using Medline,PubMed/PMC,Embase,and the Cochrane Database of Systematic Reviews up to December 2022 to identify publications on the medical management of urolithiasis.Studies that assessed dietary and pharmacologic management of urolithiasis were reviewed;studies on medical expulsive therapy were not included in this review.Results:Medical management of urolithiasis ranges from the prophylactic management of kidney stone disease to dissolution therapies.While most treatment concepts have been long established,large randomized controlled trials are scarce.Dietary modification and increased fluid intake remain cornerstones in the conservative management of urolithiasis.A major limitation for medical management of urolithiasis is poor patient compliance.Conclusion:Medical management of urolithiasis is more important in patients with recurrent urolithiasis and patients with metabolic abnormalities putting them at higher risk of developing stones.Although medical management can be effective in limiting stone recurrence,medical interventions often fail due to poor compliance.

关键词： Medicalmanagement Medical therapy Urolithiasis Kidneystonedisease

Modern internet search analytics and thyroidectomy:What are patients asking?

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

World Journal of Otorhinolaryngology-Head and Neck Surgery 2024年第1期10卷 49-58页

作者： Neeraj Suresh christian Fritz Emma De Ravin Karthik Rajasekaran Department of Otorhinolaryngology–Head&Neck Surgery University of PennsylvaniaPhiladelphiaPennsylvaniaUSA Perelman School of Medicine at the University of Pennsylvania PhiladelphiaPennsylvaniaUSA Leonard Davis Institute of Health Economics University of PennsylvaniaPhiladelphiaPennsylvaniaUSA

Objectives:Thyroidectomy is among the most commonly performed head and neck surgeries,however,limited existing information is available on topics of interest and concern to patients.Study Design:Observational.Setting:Online.Methods:A search engine optimization tool was utilized to extract metadata on google‐suggested questions that“People Also Ask”(PAA)pertaining to“thyroidectomy”and“thyroid surgery.”These questions were categorized by Rothwell criteria and topics of interest.The Journal of the American Medical Association(JAMA)benchmark criteria enabled quality assessment.Results:A total of 250 PAA questions were analyzed.Future‐oriented PAA questions describing what to expect during and after the surgery on topics such as postoperative management,risks or complications of surgery,and technical details were significantly less popular among the“thyroid surgery”group(Pg and hypocalcemia were nearly threefold more popular than those related to pain(335 and 319 vs.113 combined search engine response page count,respectively).The overall JAMA quality score remained low(2.50±1.07),despite an increasing number of patients searching for“thyroidectomy”(r(77)=0.30,P=0.007).Conclusions:Patients searching for the nonspecific term“thyroid surgery”received a curated collection of PAA questions that were significantly less likely to educate them on what to expect during and after surgery,as compared to patients with higher health literacy who search with the term“thyroidectomy.”This suggests that the content of PAA questions differs based on the presumed health literacy of the internet user.

关键词： information quality online health education search analytics thyroid surgery thyroidectomy

Melt flow,heat transfer and solidification in a flexible thin slab continuous casting mold with vertical-combined electromagnetic braking

在线全文

学校读者我要写书评

暂无评论

Journal of Iron and Steel Research(International) 2024年第2期31卷 401-415页

作者： Lin Xu Ze-feng Han christian Karcher En-gang Wang Key Laboratory of Electromagnetic Processing of Materials(Ministry of Education) Northeastern UniversityShenyang110819LiaoningChina Key Laboratory of Liaoning Province for Clean Combustion Power generation and Heating Technology Shenyang Institute of EngineeringShenyang110136LiaoningChina Institute of Thermodynamics and Fluid Mechanics Technische Universität IlmenauIlmenau98684Germany

During continuous casting of steel slabs,the application of electromagnetic braking technology(EMBr)provides an effective tool to influence solidification by controlling the pattern of melt flow in the mold.Thus,the quality of the final product can be improved considerably.A new electromagnetic braking(EMBr)method,named vertical-combined electromagnetic braking(VC-EMBr),is proposed to be applied to a flexible thin slab casting(FTSC)mold.To evaluate the beneficial effects of the VC-EMBr,the melt flow,heat transfer,and solidification processes in the FTSC mold are studied by means of numerical simulations.In detail,a Reynolds-averaged Navier–Stokes turbulence model together with an enthalpy-porosity approach was used.The numerical findings are compared with respective simulations using the traditional Ruler-EMBr.The results demonstrate that the application of the VC-EMBr contributes significantly to preventing relative slab defects.In contrast to the Ruler-EMBr,the additional vertical magnetic poles of the VC-EMBr preferentially suppress the direct impact of jet flow on the narrow face of FSTC mold and considerably diminish the level fluctuation near the meniscus region.For instance,by applying a magnetic flux density of 0.3 T,the maximum amplitude of meniscus deflection reduces by about 80%.Moreover,the braking effect of the VC-EMBr effectively improves the homogeneity of temperature distribution in the upper recirculation region and increases the solidified shell thickness along the casting direction.On this basis,the newly proposed VC-EMBr shows a beneficial effect in preventing relative slab defects for FTSC thin slab continuous casting.

关键词： Electromagnetic braking Mold Melt flow Heat transfer Solidification

A numerical and experimental comparison of heat transfer in a quasi two-dimensional packed bed

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Particuology 2024年第1期84卷 136-144页

作者： Matthias Tyslik Mirko Ebert Martin Schiemann Siegmar Wirtz christian Lessig Department of Energy Plant Technology Ruhr-University BochumGermany Institute for Simulation and graphics Otto-von-Guericke-Universität MagdeburgGermany

Heat transfer plays a major role in many industrial processes taking place in packed beds.An accurate and reliable simulation of the heat exchange between particles is therefore crucial for a reliable operation and to optimize the processes in the bed.The discrete ordinates method(DOM)provides an established numerical technique to model radiative heat transfer in granular media that offers the possibility to consider the directional dependence of the radiation propagation.In this work,DOM is compared with Monte Carlo ray tracing,which provides an alternative method for heat transfer simulations.geomet-rically simple configurations are used to investigate the influence of the angular discretization on the accuracy of the results and the computation time in both methods.The obtained insights are then transferred to a more complex configuration of a quasi two-dimensional test rig consisting of metal rods for which also experimental results are available.Our results show that both DOM and Monte Carlo ray tracing allow for an accurate simulation of heat transfer in packed beds.Monte Carlo ray tracing requires thereby computation times that are surprisingly competitive(although still somewhat slower)compared to DOM and allows for an easier computation of highly accurate reference solutions.In our preliminary comparison to the experimental test rig,Monte Carlo ray tracing also provides the advantage that it can more easily model highly specular materials such as stainless steel.Both methods are comparable for diffuse materials such as magnesium oxide.

关键词： Heat transfer Discrete ordinates method Monte Carlo ray tracing