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From the dust:extracellular vesicles as regulators of development and neuroregeneration

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Neural Regeneration Research 2024年第5期19卷 933-934页

作者： leon G.Coleman Jr the University of North Carolina at Chapel Hill School of MedicineDepartment of PharmacologyBowles Center for Alcohol StudiesChapel HillNCUSA

First impressions can have a lasting *** science,this can be especially problematic,because our lack of understanding often causes us to mislabel and thus ignore important biological *** this vein,extracellular vesicles(EVs)were once considered to be“cellular dust”.Similar to the previous concept of“junk DNA”to describe protein non-coding regions,EVs are far more than just cellular *** fact,EVs are emerging as key mediators of intracellular communication across nearly all biological *** includes peripheral immune responses(e.g.,arthropathies and sepsis),intra-organ communication(Seim et al.,2023),and a host of other physiological and pathological states(Figure 1A and B).

关键词： Figure extracellular

APPROXIMAtING tHE StAtIONARY BELLMAN EQUAtION BY HIERARCHICAL tENSOR PRODUCtS

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Journal of Computational Mathematics 2024年第3期42卷 638-661页

作者： Mathias Oster leon Sallandt Reinhold Schneider technische Universität Berlin Strasse des 17.Juni 13510623 BerlinGermany

we treat infinite horizon optimal control problems by solving the associated stationary Bellman equation numerically to compute the value function and an optimal feedback *** dynamical systems under consideration are spatial discretizations of non linear parabolic partial differential equations(Pde),which means that the Bellman equation suffers from the curse of *** non linearity is handled by the Policy Iteration algorithm,where the problem is reduced to a sequence of linear equations,which remain the computational bottleneck due to their high *** reformulate the linearized Bellman equations via the Koopman operator into an operator equation,that is solved using a minimal residual *** the Koopman operator we identify a preconditioner for operator equation,which deems essential in our numerical *** overcome computational infeasability we use low rank hierarchical tensor product approximation/tree-based tensor formats,in particular tensor trains(tt tensors)and multi-polynomials,together w.th high-dimensional quadrature,*** controlling a destabilized version of viscous Burgers and a diffusion equation w.th unstable reaction term numerical evidence is given.

关键词： Feedback control Dynamic programming Hamilton-Jacobi-Bellman tensor product approximation Variational Monte-Carlo

Superplasticity of fine-grained Mg-10Li alloy prepared by severe plastic deformation and understanding its deformation mechanisms

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Journal of Magnesium and Alloys 2024年第1期12卷 316-331页

作者： H.t.Jeong S.w.Lee w.J.Kim department of Materials Science and Engineering Hongik UniversityMapo-guSangsu-dong 72-1Seoul 121-791Republic of Korea

the superplastic behavior and associated deformation mechanisms of a fine-grained Mg-10.1 Li-0.8Al-0.6Zn alloy(LAZ1011)w.th a grain size of 3.2μm,primarily composed of the BCCβphase and a small amount of the HCPαphase,were examined in a temperature range of 473 K to 623 *** microstructural refinement of this alloy was achieved by employing high-ratio differential speed *** best superplasticity was achieved at 523 K and at strain rates of 10^(-4)-5×10^(-4)s^(-1),where tensile elongations of 550±600%were *** the heating and holding stage of the tensile samples prior to tensile loading,a significant increase in grain size was observed at temperatures above 573 ***,it was important to consider this effect when analyzing and understanding the superplastic deformation behavior and *** the investigated strain rate range,the superplastic flow at low strain rates was governed by lattice diffusion-controlled grain boundary sliding,while at high strain rates,lattice diffusion-controlled dislocation climb creep was the rate-controlling deformation *** was concluded that solute drag creep is unlikely to *** the late stages of deformation at 523 K,it was observed that grain boundary sliding led to the agglomeration of theαphase,resulting in significant strain *** mechanism maps were constructed forβ-Mg-Li alloys in the form of 2D and 3D formats as a function of strain rate,stress,temperature,and grain size,using the constitutive equations for various deformation mechanisms derived based on the data of the current tests.

关键词： Magnesium-lithium alloy Superplasticity Severe plastic deformation Grain size Grain growth

Gate-controlled supercurrent effect in dry-etched Dayem bridges of non-centrosymmetric niobium rhenium

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Nano Research 2024年第7期17卷 6575-6581页

作者： Jennifer Koch Carla Cirillo Sebastiano Battisti leon Ruf Zahra Makhdoumi Kakhaki Alessandro Paghi Armen Gulian Serafim teknowijoyo Giorgio de Simoni Francesco Giazotto Carmine Attanasio Elke Scheer Angelo Di Bernardo department of Physics University of KonstanzUniversitätsstraße 1078464 KonstanzGermany CNR-Spin c/o Universitàdegli Studi di Salernovia Giovanni Paolo II 13284084 Fisciano(SA)Italy NESt Istituto Nanoscienze-CNR and Scuola Normale SuperiorePiazza San Silvestro 1256127 PisaItaly Dipartimento di Fisica“E.R.Caianiello” Universitàdegli Studi di SalernoVia Giovanni Paolo II 13284084 Fisciano(SA)Italy Advanced Physics Laboratory Institute for Quantum StudiesChapman UniversityBurtonsvilleMD 20866USA

the application of a gate voltage to control the superconducting current flowing through a nanoscale superconducting constriction,named as gate-controlled supercurrent(GCS),has raised great interest for fundamental and technological *** gain a deeper understanding of this effect and develop superconducting technologies based on it,the material and physical parameters crucial for the GCS effect must be ***-down fabrication protocols should also be optimized to increase device scalability,although studies suggest that top-down fabricated devices are more resilient to show a ***,we investigate gated superconducting nanobridges made w.th a top-down fabrication process from thin films of the noncentrosymmetric superconductor niobium rhenium w.th varying ratios of the constituents(NbRe).Unlike other devices previously reported and made w.th a top-down approach,our NbRe devices systematically exhibit a GCS effect when they were fabricated from NbRe thin films w.th small grain size and etched in specific *** observations pave the way for the realization of top-down-made GCS devices w.th high *** results also imply that physical parameters like structural disorder and surface physical properties of the nanobridges,which can be in turn modified by the fabrication process,are crucial for a GCS observation,providing therefore also important insights into the physics underlying the GCS effect.

关键词： superconductivity non-centrosymmetric superconductors superconducting devices gated devices gate-controlled supercurrent top-down fabrication

SMILE soft X-ray Imager flight model CCD370 pre-flight device characterisation

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Earth and Planetary Physics 2024年第1期8卷 25-38页

作者： S.Parsons D.J.Hall O.Hetherington t.w.Buggey t.Arnold M.w.J.Hubbard A.Holland Centre for Electronic Imaging the Open UniversityMilton KeynesMK76AAUK

throughout the SMILE mission the satellite will be bombarded by radiation which gradually damages the focal plane devices and degrades their *** order to understand the changes of the CCD370s w.thin the soft X-ray Imager,an initial characterisation of the devices has been carried out to give a baseline performance *** CCDs have been characterised,the two flight devices and the flight spa *** has been carried out at the Open University in a bespo ke cleanroom measure ment *** results show.that there is a cluster of bright pixels in the flight spa re which increases in size w.th tempe *** at the nominal ope rating tempe rature(-120℃) it is w.thin the procure ment ***,the devices meet the specifications when ope rating at -120℃ in 6 × 6 binned frame transfer science *** se rial charge transfer inefficiency degrades w.th temperature in full frame *** any charge losses are recovered when binning/frame transfer is implemented.

关键词： CCD soft X-ray imager characterisation SMILE

A CFD Model to Evaluate Near-Surface Oil Spill from a Broken Loading Pipe in Shallow Coastal w.ters

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Fluid Dynamics & Materials Processing 2024年第1期20卷 59-77页

作者： Portia Felix Lee leon derek Gay Stefano Salon Hazi Azamathulla department of Civil and Environmental Engineering The University of the West IndiesSt.AugustineTrinidad and Tobago National Institute of Oceanography and Experimental Geophysics-OGS TriesteItaly

Oil spills continue to generate various issues and concerns regarding their effect and behavior in the marine environment,owing to the related potential for detrimental environmental,economic and social *** is essential to have a solid understanding of the ways in which oil interacts w.th the w.ter and the coastal ecosystems that are located *** study proposes a simplified model for predicting the plume-like transport behavior of heavy Bunker C fuel oil discharging downward from an acutely-angled broken pipeline located on the w.ter *** results show.that the spill overall profile is articulated in three major flow *** first,is the source field,i.e.,a region near the origin of the initial jet,followed by the intermediate or transport field,namely,the region where the jet oil flow.transitions into an underw.ter oil plume flow and starts to move horizontally,and finally,the far-field,where the oil re-surface and spreads onto the shore at a significant distance from the spill *** behavior of the oil in the intermediate field is investigated using a simplified injection-type oil spill model capable of mimicking the undersea trapping and lateral migration of an oil plume originating from a negatively buoyant jet spill.A rectangular domain w.th proper boundary conditions is used to implement the *** Projection approach is used to discretize a modified version of the Navier-Stokes equations in two dimensions.A benchmark fluid flow issue is used to verify the model and the results indicate a reasonable relationship between specific gravity and depth as well as agreement w.th the aerial data and a vertical temperature profile plot.

关键词： CFD model Navier-Stokes equations projection method w.ter surface oil spill shallow coastal w.ters

A comprehensive review of genetic causes of obesity

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world Journal of Pediatrics 2024年第1期20卷 26-39页

作者： Marcio Jose Concepcion-Zavaleta Juan Eduardo Quiroz-Aldave Maria del Carmen Durand-Vasquez Elman Rolando Gamarra-Osorio Juan del Carmen Valencia de la Cruz Claudia Mercedes Barrueto-Callirgos Susan Luciana Puelles-leon Elena de Jesus Alvarado-leon Frans Leiva-Cabrera Francisca Elena Zavaleta-Gutierrez Luis Alberto Concepcion-Urteaga Jose Paz-Ibarra Universidad Cientifica del Sur Bolivar 2150 AvenuePueblo Libre15084LimaPeru Division of Medicine Hospital de Apoyo ChepénChepenPeru Division of Family Medicine Hospital de Apoyo ChepénChepenPeru Division of Endocrinology Hospital Victor Lazarte EchegarayTrujilloPeru Division of Pediatrics Hospital de Apoyo ChepenChepenPeru Division of Internal Medicine Hospital de Apoyo ChepenChepenPeru Division of Genetics Universidad Nacional de TrujilloTrujilloPeru Division of Neonatology Hospital Belen de TrujilloTrujilloPeru Division of Internal Medicine Universidad Nacional de TrujilloTrujilloPeru department of Medicine School of MedicineUniversidad Nacional Mayor de San MarcosLimaPeru

Background Obesity is a multifactorial chronic disease w.th a high,increasing worldwide *** causes account for 7%of the cases in children w.th extreme *** sources this narrative review was conducted by searching for papers published in the PubMed/MEDLINE,Embase and SciELO databases and included 161 *** search used the following search terms:"obesity","obesity and genetics","leptin","Prader-willi syndrome",and"melanocortins".the types of studies included were systematic reviews,clinical trials,prospective cohort studies,cross-sectional and prospective studies,narrative reviews,and case *** the leptin-melanocortin pathway is primarily responsible for the regulation of appetite and body ***,several important aspects of the pathophysiology of obesity remain *** causes of obesity can be grouped into syndromic,monogenic,and polygenic causes and should be assessed in children w.th extreme obesity before the age of 5 years,hyperphagia,or a family history of extreme obesity.A microarray study,an analysis of the melanocortin type 4 receptor gene mutations and leptin levels should be performed for this *** are three therapeutic levels:lifestyle modifications,pharmacological treatment,and bariatric *** Genetic study technologies are in constant development;however,we are still far from having a personalized approach to genetic causes of obesity.A significant proportion of the affected individuals are associated w.th genetic causes;however,there are still barriers to its approach,as it continues to be underdiagnosed.

关键词： Leptin Melanocortin Obesity Prader-willi syndrome Precision medicine

Predictors of survival in autoimmune liver disease overlap syndromes

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world Journal of Hepatology 2024年第9期16卷 1269-1277页

作者： Dujinthan Jayabalan Yi Huang Luis Calzadilla-Bertot Malik Janjua Bastiaan de Boer John Joseph wendy Cheng Simon Hazeldine Briohny w Smith Gerry C MacQuillan Michael C wallace George Garas leon A Adams Gary P Jeffrey Medical School University of Western AustraliaNed-lands 6009Western AustraliaAustralia department of Hepatology Sir Charles Gairdner HospitalNedlands 6009Western AustraliaAustralia department of Anatomical Pathology PathWest Laboratory MedicineNedlands 6009Western AustraliaAustralia department of Gastroenterology and Hepatology Royal Perth HospitalPerth 6000Western AustraliaAustralia department of Gastroenterology and Hepatology Fiona Stanley HospitalMurdoch 6150Western AustraliaAustralia Medical School University of Western AustraliaNedl-ands 6009Western AustraliaAustralia

BACKGROUND Survival in patients w.th autoimmune liver disease overlap syndromes(AILDOS)compared to those w.th single autoimmune liver disease is *** to investigate the survival of patients w.th AILDOS and assess the accuracy of non-invasive serum models for predicting liver-related *** Patients w.th AILDOS were defined as either autoimmune hepatitis and primary biliary cholangitis overlap(AIH-PBC)or autoimmune hepatitis and primary sclerosing cholangitis overlap(AIH-PSC)and were identified from three tertiary centres for this cohort ***-related death or transplantation(liver-related mortality)was determined using a population-based data linkage *** scores for liver-related death were compared for accuracy[including liver outcome score(LOS),Hepascore,Mayo Score,model for end-stage liver disease(MELD)score and MELD incorporated w.th serum sodium(MELD-Na)score].RESULtS twenty-two AILDOS patients were followed for a median of 3.1 years(range,0.35-7.7).Fourteen were female,the median age was 46.7 years(range,17.8 to 82.1)and median Hepascore was 1(range,0.07-1).At five years post enrolment,57%of patients remained free from liver-related mortality(74%AIH-PBC,27%AIH-PSC).there was no significant difference in survival between AIH-PBC and *** was a significant predictor of liver-related mortality(Ptients w.th AIH-PBC(n=14)but not AIH-PSC(n=8).A LOS cut-point of 6 discriminated liver-related mortality in AIH-PBC patients(P=0.012,log-rank test,100%sensitivity,77.8%specificity)(Harrell's C-statistic 0.867).the MELD score,MELD-Na score and Mayo Score were not predictive of liver-related mortality in any *** Survival in the rare,AILDOS is *** current study supports the LOS as a predictor of liver-related mortality in AIH-PBC *** trials investigating predictors of survival in AILDOS are required.

关键词： Autoimmune liver disease overlap syndromes Liver outcome score Liver-related death Hepascore Autoimmune hepatitis Primary biliary cholangitis Primary sclerosing cholangitis

the CCD instrument background of the SMILE SXI

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Earth and Planetary Physics 2024年第1期8卷 15-24页

作者： M.w.J.Hubbard O.Hetherington D.J.Hall t.w.Buggey S.Parsons t.Arnold A.Holland C.Pagani S.Sembay Centre for Electronic Imaging The Open UniversityMilton KeynesMK76AAUK X-ray and Observational Astronomy Group Department of Physics&AstronomyUniversity of LeicesterLE17RHUK

the ESA and CAS SMILE mission orbit is highly elliptical and will pass through multiple radiation *** Soft X-ray Imager(SXI)instrument aboard has a radiation shutter door designed to close when the surrounding radiation flux is *** shutter door will close when passing below an altitude threshold to protect against trapped particles in the Earth’s Van Allen ***,two radiation environments can be approximated based on the shutter door position:open and *** instrument background for the CCDs(Charge-Coupled devices)that form the focal plane array of the SXI were evaluated for the two *** to the correlation of the space environment w.th the solar cycle,the solar minima and maxima,the background was also evaluated at these two *** results demonstrated that the highest instrument background will occur during solar minima due to the main contributing source being Galactic Cosmic Rays(GCRs).It was also found that the open background was highest for solar minima and that the closed background was highest during solar *** is due to the radiation shutter door acting as a scattering centre and the changes in the energy flux distribution of the GCRs between the two solar extremes.

关键词： instrument background X-ray astronomy space radiation