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Finding the magnetopause location using soft X-ray observations and a statistical inverse method

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Earth and Planetary Physics 2024年第1期8卷 184-203页

作者： Gonzalo Cucho-Padin Hyunju Connor Jaewoong Jung Brian Walsh david G.Sibeck Space Weather Laboratory NASA Goddard Space Flight CenterGreenbeltMDUSA Department of Physics The Catholic University of AmericaWashingtonDCUSA Geospace Physics Laboratory NASA Goddard Space Flight CenterGreenbeltMDUSA Astronomy Department University of Maryland College ParkCollege ParkMDUSA Center for Space Physics Department of Mechanical EngineeringBoston UniversityBostonMAUSA

Variability in the location and shape of the dayside magnetopause is attributed to magnetic reconnection,a fundamental process that enables the transfer of mass,energy,and momentum from the solar wind into the magnetosphere.The spatial and temporal properties of the magnetopause,under varying solar and magnetospheric conditions,remain largely unknown because empirical studies using in-situ observations are challenging to interpret.Global wide field-of-view(FOV)imaging is the only means to simultaneously observe the spatial distribution of the plasma properties over the vast dayside magnetospheric region and,subsequently,quantify the energy transport from the interplanetary medium into the terrestrial magnetosphere.Two upcoming missions,ESA/CAS SmILE and NASA’s LEXI will provide wide-field imagery of the dayside magnetosheath in soft X-rays,an emission generated by charge exchange interactions between high charge-state heavy ions of solar wind origin and exospheric neutral atoms.High-cadence two-dimensional observations of the magnetosheath will allow the estimation of dynamic properties of its inner boundary,the magnetopause,and enable studies of its response to changes in the solar wind dynamic pressure and interplanetary magnetic field orientation.This work introduces a statistically-based estimation approach based on inverse theory to estimate the spatial distribution of magnetosheath soft X-ray emissivities and,with this,identify the location of the magnetopause over the Sun−Earth line.To do so,we simulate the magnetosheath structure using the mHD-based OpenGGCm model and generate synthetic soft X-ray images using LEXI’s orbit and attitude information.Our results show that 3-D estimations using the described statistically-based technique are robust against Poisson-distributed shot noise inherent to soft X-ray images.Also,our proposed methodology shows that the accuracy of both three-dimensional(3-D)estimation and the magnetopause standoff distance calculation highly depends on the observational point.

关键词： magnetopause soft X-ray tomography

An Investigation into Forced Convection of a Nanofluid Flowing in a Rectangular microchannel under the Influence of a magnetic Field

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Fluid Dynamics & materials Processing 2024年第2期20卷 311-323页

作者： muataz S.Alhassan Ameer A.Alameri Andrés Alexis Ramírez-Coronel I.B.Sapaev Azher m.Abed david-Juan Ramos-Huallpartupa Rahman S.Zabibah Division of Advanced Nanomaterial Technologies Scientific Research CenterAl-Ayen UniversityThi-QarIraq Department of Chemistry College of ScienceUniversity of BabylonBabylonIraq Research Group in Educational Statistics National University of EducatiosnAzoguesEcuador Department Physics and Chemistry Tashkent Institute of Irrigation and Agricultural Mechanization EngineersNational Research UniversityTashkentUzbekistan Akfa University TashkentUzbekistan New Uzbekistan University TashkentUzbekistan Department of Airconditioning and Refrigeration Engineering Al-Mustaqbal University CollegeHilla51001Iraq Academic Department of Agro-Industrial Engineering and Technology Universidad Nacional JoséMaría ArguedasApurimacPerú The Islamic University NajafIraq

In line with recent studies,where it has been shown that nanoﬂuids containing graphene have a stronger capacity to boost the heat transfer coefﬁcient with respect to ordinary nanoﬂuids,experiments have been conducted using water with cobalt ferrite/graphene nanoparticles.In particular,a circular channel made of copper subjected to a constant heatﬂux has been considered.As nanoparticles are sensitive to the presence of a magneticﬁeld,different conditions have been examined,allowing both the strength and the frequency of such aﬁeld to span relatively wide ranges and assuming different concentrations of nanoparticles.According to theﬁndings,the addition of nanoparticles to theﬂuid causes its rotation speed to increase by a factor of two,whereas ultraviolet radiation plays a negligible role.The amount of time required to attain the maximum rotation speed of the nanoﬂuid and the Nusselt number have been measured under both constant and alternating magneticﬁelds for a ferroﬂuid with a concentration of 0.5%and atﬂow Reynolds number of 550 and 1750.

关键词： Nano fluid rectengular tube magnetic field

Old-growth mixed dipterocarp forests show variable losses and gains in aboveground biomass and standing carbon over forty years

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Forest Ecosystems 2024年第1期11卷 14-23页

作者： Sisira Ediriweera Champika Bandara Tithira Lakkana Shanika Jayasinghe david Woodbury Arun Dayanandan B.m.P.Singhakumara Xiangcheng mi I.A.U.N.Gunatilleke C.V.S.Gunatilleke mark SAshton Department of Science and Technology Uva Wellassa UniversityBadullaSri Lanka The Forest School Yale School of the EnvironmentYale UniversityNew HavenCT06511USA Department of Forestry and Environmental Science University of Sri JayewardenepuraNugegodaSri Lanka State Key Laboratory of Vegetation and Environmental Change Institute of BotanyChinese Academy of SciencesBeijing100093China Botany Department University of PeradeniyaPeradeniyaSri Lanka

Background:No studies have documented long-term trends in aboveground biomass(AGB)for mixed-dipterocarp forests(mDF),the dominant rain forest type in tropical wet equatorial Asia.In our study,we sought to document such trends over forty years across three sites representing lowland to lower montane elevations.methods:To do this,we established fifty 100 m×25 m plots in 1978 across three sites sampled along an elevation gradient,identified as mature old-growth forest.We measured trees for diameter at breast height that we identified to species and tagged.We took wood samples to calculate species wood-specific gravity.We re-measured plots in 1998 and again in 2018.Results:We show standing AGB for all sites combined to be 517.52 mg·ha^(-1)in 1978,but this declined by 17%over 40 years to 430.11 mg·ha^(-1).No differences exist among sites in AGB primarily because of considerable within site variation;but interactions of time with site show declines across sites were not uniform,one remained about the same.Relatively few species represented a high proportion of the AGB with the top five species comprising between 34%and 65%,depending upon site and year sampled.One species,mesua nagassarium,represented a disproportionately large amount of AGB and decline over time,particularly at the low elevation site.Conclusions:Our results are directly relevant to estimating AGB and standing carbon sequestered in mDF.Our study is the first to demonstrate varying but overall,declining trends in amounts of AGB among forests making predictions of biomass and standing carbon in mDF difficult over wide regions.

关键词： Western ghats Shorea spp. Southeast Asia Sri Lanka Tropical rain forest Wood specific gravity

A comprehensive look at the psychoneuroimmunoendocrinology of spinal cord injury and its progression: mechanisms and clinical opportunities

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military medical Research 2024年第2期11卷 228-267页

作者： miguel A.Ortega Oscar Fraile-martinez Cielo García-montero Sergio Haro miguel Ángel Álvarez-mon Diego De Leon-Oliva Ana m.Gomez-Lahoz Jorge monserrat mar Atienza-Pérez david Díaz Elisa Lopez-Dolado melchor Álvarez-mon Department of medicine and medical Specialities University of Alcala28801 Alcala de HenaresSpain Ramón y Cajal Institute of Sanitary Research(IRYCIS) 28034 MadridSpain Department of Psychiatry and mental Health Hospital Universitario Infanta Leonor28031 MadridSpain Service of Rehabilitation National Hospital for Paraplegic PatientsCarr.de la PeraledaS/N45004 ToledoSpain Immune System Diseases‑Rheumatology Service and Internal medicine University Hospital Príncipe de Asturias(CIBEREHD)28806 Alcala de HenaresSpain

Spinal cord injury(SCI)is a devastating and disabling medical condition generally caused by a traumatic event(primary injury).This initial trauma is accompanied by a set of biological mechanisms directed to ameliorate neural damage but also exacerbate initial damage(secondary injury).The alterations that occur in the spinal cord have not only local but also systemic consequences and virtually all organs and tissues of the body incur important changes after SCI,explaining the progression and detrimental consequences related to this condition.Psychoneuroimmunoendocrinology(PNIE)is a growing area of research aiming to integrate and explore the interactions among the different systems that compose the human organism,considering the mind and the body as a whole.The initial traumatic event and the consequent neurological disruption trigger immune,endocrine,and multisystem dysfunction,which in turn affect the patient's psyche and well-being.In the present review,we will explore the most important local and systemic consequences of SCI from a PNIE perspective,defining the changes occurring in each system and how all these mechanisms are interconnected.Finally,potential clinical approaches derived from this knowledge will also be collectively presented with the aim to develop integrative therapies to maximize the clinical management of these patients.

关键词： Spinal cord injury(SCI) Psychoneuroimmunoendocrinology(PNIE) Secondary injury Immunoinflammatory dysfunction Gut microbiota Translational opportunities

LKB1 depletion-mediated epithelial-mesenchymal transition induces fibroblast activation in lung fibrosis

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Genes & Diseases 2024年第3期11卷 417-426页

作者： Zijian Xu Elizabeth R.Davies Liudi Yao Yilu Zhou Juanjuan Li Aiman Alzetani Ben G.marshall david Hancock Tim Wallis Julian Downward Rob m.Ewing Donna E.Davies mark G.Jones Yihua Wang Biological Sciences Faculty of Environmental and Life SciencesUniversity of SouthamptonSouthampton SO171BJUK clinical and Experimental Sciences Faculty of MedicineUniversity of SouthamptonSouthampton SO166YDUK Institute for Life Sciences University of SouthamptonSouthampton SO171BJUK NIHR Southampton Biomedical Research Centre University Hospital SouthamptonSouthampton SO166YDUK University Hospital Southampton Southampton SO166YDUK Oncogene Biology The Francis Crick InstituteLondon NW11ATUK

The factors that determine fibrosis progression or normal tissue repair are largely unknown.We previously demonstrated that autophagy inhibition-mediated epithelial-mesenchymal transition(EmT)in human alveolar epithelial type Il(ATIl)cells augments local myofibroblast differentiation in pulmonary fibrosis by paracrine signaling.Here,we report that liver kinase B1(LKB1)inactivation in ATIl cells inhibits autophagy and induces EmT as a conse-quence.In IPF lungs,this is caused by the down-regulation of CAB39L,a key subunit within the LKB1 complex.3D co-cultures of ATIl cells and mRC5 lung fibroblasts coupled with RNA sequencing(RNA-seq)confirmed that paracrine signaling between LKB1-depleted ATIl cells and fibroblasts augmented myofibroblast differentiation.Together,these data suggest that reduced autophagy caused by LKB1 inhibition can induce EmT in ATIl cells and contribute to fibrosis via aberrant epithelial-fibroblast crosstalk.

关键词： CAB39L Crosstalk EmT LKB1 Pulmonary fibrosis

Theory of Flexural Shear, Bending and Torsion for a Thin-Walled Beam of Open Section

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World Journal of mechanics 2024年第3期14卷 23-53页

作者： david W. A. Rees Abdelraouf m. Sami Alsheikh College of Engineering and Design Brunel University Uxbridge UK

Aspects of the general Vlasov theory are examined separately as applied to a thin-walled channel section cantilever beam under free-end end loading. In particular, the flexural bending and shear that arise under transverse shear and axial torsional loading are each considered theoretically. These analyses involve the location of the shear centre at which transverse shear forces when applied do not produce torsion. This centre, when taken to be coincident with the centre of twist implies an equivalent reciprocal behaviour. That is, an axial torsion applied concentric with the shear centre will twist but not bend the beam. The respective bending and shear stress conversions are derived for each action applied to three aluminium alloy extruded channel sections mounted as cantilevers with a horizontal principal axis of symmetry. Bending and shear are considered more generally for other thin-walled sections when the transverse loading axes at the shear centre are not parallel to the section = s centroidal axes of principal second moments of area. The fixing at one end of the cantilever modifies the St Venant free angular twist and the free warping displacement. It is shown from the Wagner-Kappus torsion theory how the end constrained warping generates an axial stress distribution that varies with the length and across the cross-section for an axial torsion applied to the shear centre. It should be mentioned here for wider applications and validation of the Vlasov theory that attendant papers are to consider in detail bending and torsional loadings applied to other axes through each of the centroid and the web centre. Therein, both bending and twisting arise from transverse shear and axial torsion applied to each position being displaced from the shear centre. Here, the influence of the axis position upon the net axial and shear stress distributions is to be established. That is, the net axial stress from axial torsional loading is identified with the sum of axial stress due to bending and axial stress arising from con

关键词： Thin Wall Theory Cantilever Beam Open Channel Section Principal Axes Flexure Transverse Shear Torsion Shear Centre Shear Flow Warping Fixed-End Constraint

Estimating the subsolar magnetopause position from soft X-ray images using a low-pass image filter

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Earth and Planetary Physics 2024年第1期8卷 173-183页

作者： Hyangpyo Kim Hyunju K.Connor Jaewoong Jung Brian m.Walsh david Sibeck Kip D.Kuntz Frederick S.Porter Catriana K.Paw U Rousseau A.Nutter Ramiz Qudsi Rumi Nakamura michael Collier Space Research Institute Austrian Academy of Sciences8042 GrazAustria Geophysical Institute University of Alaska FairbanksFairbanksAlaska 99775USA National Aeronautics and Space Administration(NASA)Goddard Space Flight Center GreenbeltMaryland 20771USA Astronomy Department University of Maryland College ParkCollege ParkMaryland 20742USA Center for Space Physics Boston UniversityBostonMassachusetts 02215USA Department of Physics and Astronomy Johns Hopkins UniversityBaltimoreMaryland 21218USA Howard University WashingtonDC 20059USA

The Lunar Environment heliospheric X-ray Imager(LEXI)and Solar wind magnetosphere Ionosphere Link Explorer(SmILE)missions will image the Earth’s dayside magneto pause and cusps in soft X-rays after their respective launches in the near future,to specify glo bal magnetic reconnection modes for varying solar wind conditions.To suppo rt the success of these scientific missions,it is critical to develop techniques that extract the magnetopause locations from the observed soft X-ray images.In this research,we introduce a new geometric equation that calculates the subsolar magnetopause position(RS)from a satellite position,the look direction of the instrument,and the angle at which the X-ray emission is maximized.Two assumptions are used in this method:(1)The look direction where soft X-ray emissions are maximized lies tangent to the magnetopause,and(2)the magnetopause surface near the subsolar point is almost spherical and thus RSis nea rly equal to the radius of the magneto pause curvature.We create synthetic soft X-ray images by using the Open Geospace General Circulation model(OpenGGCm)global magnetohydrodynamic model,the galactic background,the instrument point spread function,and Poisson noise.We then apply the fast Fourier transform and Gaussian low-pass filte rs to the synthetic images to re move noise and obtain accurate look angles for the soft X-ray pea ks.From the filte red images,we calculate RS and its accuracy for different LEXI locations,look directions,and solar wind densities by using the OpenGGCm subsolar magnetopause location as ground truth.Our method estimates RS with an accuracy of10 cm-3.The accuracy improves for greater solar wind densities and during southward interplanetary magnetic fields.The method ca ptures the magnetopause motion during southwa rd interplaneta ry magnetic field turnings.Consequently,the technique will enable quantitative analysis of the magnetopause motion and help reveal the dayside reconnection modes for dynamic solar wind con

关键词： soft X-ray magnetopause reconnection low-pass filter LEXI SmILE

Protective effects of cyclosporine and its analog NIm-811 in a murine model of hepatic ischemia-reperfusion injury

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Liver Research 2024年第1期8卷 46-53页

作者： Joshua Hefler Rena Pawlick Braulio A.marfil-Garza Aducio Thiesen Nerea Cuesta-Gomez Sanaz Hatami Darren H.Freed Constantine Karvellas david L.Bigam A.m.James Shapiro Department of Surgery Faculty of Medicine&DentistryUniversity of AlbertaEdmontonABCanada Department of medicine Faculty of Medicine&DentistryUniversity of AlbertaEdmontonABCanada CHRISTUS-LatAm Hub Excellence&Innovation Center MonterreyMexico Alberta Diabetes Institute University of AlbertaEdmontonABCanada Clinical Islet Transplant Program University of AlbertaEdmontonABCanada Department of Laboratory medicine&Pathology Faculty of Medicine&DentistryUniversity of AlbertaEdmontonABCanada

Background and aim:The liver is susceptible to ischemia-reperfusion injury(IRI)during hepatic surgery,when the vessels are compressed to control bleeding,or liver transplantation,when there is an obligate period of ischemia.The hallmark of IRI comprises mitochondrial dysfunction,which generates reactive oxygen species,and cell death through necrosis or apoptosis.Cyclosporine(CsA),which is a well-known immunosuppressive agent that inhibits calcineurin,has the additional effect of inhibiting the mito-chondrial permeability transition pore(mPTP),thereby,preventing mitochondrial swelling and injury.NIm-811,which is the nonimmunosuppressive analog of CsA,has a similar effect on the mPTP.In this study,we tested the effect of both agents on mitigating warm hepatic IRI in a murine model.materials and methods:Before ischemic insult,the mice were administered with intraperitoneal normal saline(control);CsA at 2.5,10,or 25 mg/kg;or NIm-811 at 10 mg/kg.Thereafter,the mice were subjected to partial warm hepatic ischemia by selective pedicle clamping for 60 min,followed by 6 h of recovery after reperfusion.Serum alanine transaminase(ALT)was measured,and the liver tissue was examined histologically for the presence of apoptosis and the levels of inflammatory cytokines.Results:Compared with the control mice,the mice treated with 10 and 25 mg/kg of CsA and NIm-811 had significantly lower ALT levels(Pmoreover,the liver tissue showed reduced histological injury scores after treatment with CsA at 2.5,10,and 25 mg/kg and NIm-811(P=0.041,ment with CsA at all doses(P=0.012,0.007,andmmatory cyto-kines,particularly interleukin(IL)-1β,IL-2,IL-4,IL-10,and keratinocyte chemoattractant/human growth-regulated oncogene significantly decreased in the mice treated with the highest dose of CsA(25 mg/kg)than those in the control mice.Conclusions:Premedication with CsA or NIm-811 mitig

关键词： Cyclosporine(CsA) Cyclosporine analogue Liver surgery Ischemia-reperfusion injury(IRI) Animal model NIm-811

2024 Adult Compendium of Physical Activities:A third update of the energy costs of human activities

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Journal of Sport and Health Science 2024年第1期13卷 6-12页

作者： Stephen D.Herrmann Erik A.Willis Barbara E.Ainsworth Tiago V.Barreira mary Hastert Chelsea L.Kracht John m.Schuna Jr. Zhenghui Cai minghui Quan Catrine Tudor-Locke melicia C.Whitt-Glover david R. Jacobs Jr. Kansas Center for metabolism and Obesity Research University of Kansas Medical CenterKansas CityKS 66160USA Division of Physical Activity and Weight management Department of Internal MedicineUniversity of Kansas Medical CenterKansas CityKS 66160USA Center for Health Promotion and Disease Prevention University of North Carolina at Chapel HillChapel HillNC 27599USA College of Health Solutions Arizona State UniversityPhoenixAZ 85003USA School of Exercise and Health Shanghai University of SportShanghai 200438China Exercise Science Department Syracuse UniversitySyracuseNY 13244USA Clinical Sciences Division Pennington Biomedical Research CenterBaton RougeLA 70808USA School of Exercise and Sport Science Oregon State UniversityCorvallisOR 97331USA College of Health and Human Services University of North Carolina at CharlotteCharlotteNC 28223USA Gramercy Research Group KnightdaleNC 27545USA Division of Epidemiology and Community Health School of Public HealthUniversity of MinnesotaMinneapolisMN 55454USA

Background:The Compendium of Physical Activities was published in 1993 to improve the comparability of energy expenditure values assigned to self-reported physical activity(PA)across studies.The original version was updated in 2000,and again in 2011,and has been widely used to support PA research,practice,and public health guidelines.methods:This 2024 update was tailored for adults 19-59 years of age by removing data from those≥60 years.Using a systematic review and supplementary searches,we identified new activities and their associated measured metabolic equivalent(mET)values(using indirect calorimetry)published since 2011.We replaced estimated mETs with measured values when possible.Results:We screened 32,173 abstracts and 1507 full-text papers and extracted 2356 PA energy expenditure values from 701 papers.We added303 new PAs and adjusted 176 existing mET values and descriptions to reflect the addition of new data and removal of mETs for older adults.We added a major Heading(Video Games).The 2024 Adult Compendium includes 1114 PAs(912 with measured and 202 with estimated values)across 22 major Headings.Conclusion:This comprehensive update and refinement led to the creation of The 2024 Adult Compendium,which has utility across research,public health,education,and healthcare domains,as well as in the development of consumer health technologies.The new website with the complete lists of PAs and supporting resources is available at https://***.

关键词： Adults Energy expenditure Exercise mET Physical Activities