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Hybrid-Vlasov sim.lation of soft X-ray em.ssions at the Earth’s dayside m.gnetospheric boundaries

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Earth and Planetary Physics 2024年第1期8卷 70-88页

作者： m.Grandin H.K.connor S.Hoilijoki m.Battarbee Y.Pfau-Kem.f U.Ganse K.Papadakis m.Palm.oth Departm.nt of Physics University of HelsinkiHelsinkiFinland NASA Goddard Space Flight Center GreenbeltMD20771USA Space and Earth Observation Centre Finnish Meteorological InstituteHelsinkiFinland

Solar wind charge exchange produces em.ssions in the soft X-ray energy range which can enable the study of near-Earth space regions such as the m.gnetopause,the m.gnetosheath and the polar cusps by rem.te sensing techniques.The Solar wind m.gnetosphere Ionosphere Link Explorer(Sm.LE)and Lunar Environm.nt heliospheric X-ray Im.ger(LEXI)m.ssions aim.to obtain soft Xray im.ges of near-Earth space thanks to their Soft X-ray Im.ger(SXI)instrum.nts.While earlier m.deling works have already sim.lated soft X-ray im.ges as m.ght be obtained by Sm.LE SXI during its m.ssion,the num.rical m.dels used so far are all based on the m.gnetohydrodynam.cs description of the space plasm..To investigate the possible signatures of ion-kinetic-scale processes in soft Xray im.ges,we use for the first tim. a global hybrid-Vlasov sim.lation of the geospace from.the Vlasiator m.del.The sim.lation is driven by fast and tenuous solar wind conditions and purely southward interplanetary m.gnetic field.We first produce global X-ray im.ges of the dayside near-Earth space by placing a virtual im.ging satellite at two different locations,providing m.ridional and equatorial views.We then analyze regional features present in the im.ges and show that they correspond to signatures in soft X-ray em.ssions of m.rrorm.de wave structures in the m.gnetosheath and flux transfer events(FTEs)at the m.gnetopause.Our results suggest that,although the tim. scales associated with the m.tion of those transient phenom.na will likely be significantly sm.ller than the integration tim. of the Sm.LE and LEXI im.gers,m.rror-m.de structures and FTEs can cum.latively produce detectable signatures in the soft X-ray im.ges.For instance,a local increase by 30%in the proton density at the dayside m.gnetopause resulting from.the transit of m.ltiple FTEs leads to a 12%enhancem.nt in the line-of-sight-and tim.-integrated soft X-ray em.ssivity originating from.this region.Likewise,a proton density increase by 14%in the m.gnetosheath associated with m.rror-m.de structures can resu

关键词： m.gnetosphere m.gnetosheath num.rical sim.lation Sm.LE LEXI soft X-ray em.ssions hybrid-Vlasov m.del polar cusp flux transfer events m.rror-m.de waves

Finding the m.gnetopause location using soft X-ray observations and a statistical inverse m.thod

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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 Departm.nt of Physics The Catholic University of AmericaWashingtonDCUSA Geospace Physics Laboratory NASA Goddard Space Flight CenterGreenbeltMDUSA Astronom. Departm.nt University of Maryland College ParkCollege ParkMDUSA Center for Space Physics Department of Mechanical EngineeringBoston UniversityBostonMAUSA

Variability in the location and shape of the dayside m.gnetopause is attributed to m.gnetic reconnection,a fundam.ntal process that enables the transfer of m.ss,energy,and m.m.ntum.from.the solar wind into the m.gnetosphere.The spatial and tem.oral properties of the m.gnetopause,under varying solar and m.gnetospheric conditions,rem.in largely unknown because em.irical studies using in-situ observations are challenging to interpret.Global wide field-of-view(FOV)im.ging is the only m.ans to sim.ltaneously observe the spatial distribution of the plasm. properties over the vast dayside m.gnetospheric region and,subsequently,quantify the energy transport from.the interplanetary m.dium.into the terrestrial m.gnetosphere.Two upcom.ng m.ssions,ESA/CAS Sm.LE and NASA’s LEXI will provide wide-field im.gery of the dayside m.gnetosheath in soft X-rays,an em.ssion generated by charge exchange interactions between high charge-state heavy ions of solar wind origin and exospheric neutral atom..High-cadence two-dim.nsional observations of the m.gnetosheath will allow the estim.tion of dynam.c properties of its inner boundary,the m.gnetopause,and enable studies of its response to changes in the solar wind dynam.c pressure and interplanetary m.gnetic field orientation.This work introduces a statistically-based estim.tion approach based on inverse theory to estim.te the spatial distribution of m.gnetosheath soft X-ray em.ssivities and,with this,identify the location of the m.gnetopause over the Sun−Earth line.To do so,we sim.late the m.gnetosheath structure using the m.D-based OpenGGCm.m.del and generate synthetic soft X-ray im.ges using LEXI’s orbit and attitude inform.tion.Our results show that 3-D estim.tions using the described statistically-based technique are robust against Poisson-distributed shot noise inherent to soft X-ray im.ges.Also,our proposed m.thodology shows that the accuracy of both three-dim.nsional(3-D)estim.tion and the m.gnetopause standoff distance calculation highly depends on the observational point.

关键词： m.gnetopause soft X-ray tom.graphy

high-repetition-rate laser-driven fusion;laser±plasm. interaction;liquid target;neutron detectors

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High Power Laser Science and Engineering 2024年第1期12卷 13-23页

作者： Benjam.n m.Knight connor m.Gautam.Colton R.Stoner Bryan V.Egner Joseph R.Sm.th Chris m.Orban Juan J.m.nfredi Kyle D.Frische m.chael L.Dexter Enam.A.Chowdhury Anil K.Patnaik Departm.nt of Engineering Physics Air Force Institute of TechnologyWPAFBOHUSA Physics Departm.nt Marietta CollegeMariettaOHUSA Departm.nt of Physics The Ohio State UniversityColumbusOHUSA Departm.nt of m.terials Science and Engineering and Department of Electrical and Computer ScienceThe Ohio State UniversityColumbusOHUSA Intense Energy Solutions LLCPlain CityOHUSA

We present detailed characterization of laser-driven fusion and neutron production(-10^(5)/second) using 8 m., 40 fs laser pulses on a thin(<1 μm. D_2O liquid sheet em.loying a m.asurem.nt suite. At relativistic inte... 详细信息

We present detailed characterization of laser-driven fusion and neutron production(-10^(5)/second) using 8 m., 40 fs laser pulses on a thin(m. D_2O liquid sheet em.loying a m.asurem.nt suite. At relativistic intensity(~ 5 × 10^(18)W/cm.(2))and high repetition rate(1 kHz), the system.produces deuterium.deuterium.D-D) fusion, allowing for consistent neutron generation. Evidence of D-D fusion neutron production is verified by a m.asurem.nt suite with three independent detection system.: an EJ-309 organic scintillator with pulse-shape discrim.nation, a ~3He proportional counter and a set of 36 bubble detectors. Tim.-of-flight analysis of the scintillator data shows the energy of the produced neutrons to be consistent with 2.45 m.V. Particle-in-cell sim.lations using the WarpX code support significant neutron production from.D-D fusion events in the laser±target interaction region. This high-repetition-rate laser-driven neutron source could provide a low-cost, on-dem.nd test bed for radiation hardening and im.ging applications.

关键词： high-repetition-rate laser-driven fusion laser-plasm. interaction liquid target neutron detectors

Estim.ting the subsolar m.gnetopause position from.soft X-ray im.ges using a low-pass im.ge 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 Ram.z Qudsi Rum. Nakam.ra m.chael Collier Space Research Institute Austrian Academy of Sciences8042 GrazAustria Geophysical Institute University of Alaska FairbanksFairbanksAlaska 99775USA National Aeronautics and Space Adm.nistration(NASA)Goddard Space Flight Center GreenbeltMaryland 20771USA Astronom. Departm.nt University of Maryland College ParkCollege ParkMaryland 20742USA Center for Space Physics Boston UniversityBostonMassachusetts 02215USA Departm.nt of Physics and Astronom. Johns Hopkins UniversityBaltimoreMaryland 21218USA Howard University WashingtonDC 20059USA

The Lunar Environm.nt heliospheric X-ray Im.ger(LEXI)and Solar wind m.gnetosphere Ionosphere Link Explorer(Sm.LE)m.ssions will im.ge the Earth’s dayside m.gneto pause and cusps in soft X-rays after their respective launches in the near future,to specify glo bal m.gnetic reconnection m.des for varying solar wind conditions.To suppo rt the success of these scientific m.ssions,it is critical to develop techniques that extract the m.gnetopause locations from.the observed soft X-ray im.ges.In this research,we introduce a new geom.tric equation that calculates the subsolar m.gnetopause position(RS)from.a satellite position,the look direction of the instrum.nt,and the angle at which the X-ray em.ssion is m.xim.zed.Two assum.tions are used in this m.thod:(1)The look direction where soft X-ray em.ssions are m.xim.zed lies tangent to the m.gnetopause,and(2)the m.gnetopause surface near the subsolar point is alm.st spherical and thus RSis nea rly equal to the radius of the m.gneto pause curvature.We create synthetic soft X-ray im.ges by using the Open Geospace General Circulation m.del(OpenGGCm.global m.gnetohydrodynam.c m.del,the galactic background,the instrum.nt point spread function,and Poisson noise.We then apply the fast Fourier transform.and Gaussian low-pass filte rs to the synthetic im.ges to re m.ve noise and obtain accurate look angles for the soft X-ray pea ks.From.the filte red im.ges,we calculate RS and its accuracy for different LEXI locations,look directions,and solar wind densities by using the OpenGGCm.subsolar m.gnetopause location as ground truth.Our m.thod estim.tes RS with an accuracy of10 cm.3.The accuracy im.roves for greater solar wind densities and during southward interplanetary m.gnetic fields.The m.thod ca ptures the m.gnetopause m.tion during southwa rd interplaneta ry m.gnetic field turnings.Consequently,the technique will enable quantitative analysis of the m.gnetopause m.tion and help reveal the dayside reconnection m.des for dynam.c solar wind con

关键词： soft X-ray m.gnetopause reconnection low-pass filter LEXI Sm.LE

Helicobacter pylori:High dose am.xicillin does not im.rove prim.ry or secondary eradication rates in an Irish cohort

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World Journal of Clinical Cases 2024年第16期12卷 2773-2779页

作者： Conor Costigan Aoife m.O'Sullivan Jim.O'Connell Shreyashee Sengupta Thom.s Butler Stephen m.lloy Fintan John O'Hara Barbara Ryan Niall Breslin Sarah O'Donnell Anthony O'connor Sinead Sm.th Deirdre m.Nam.ra Trinity Academ.c Gastroenterology Group School of Medicine-Trinity College DublinDublin D2Ireland Departm.nt of Gastroenterology Tallaght University HospitalDublin D24 NR0AIreland

BACKGROUND Helicobacter pylori(H.pylori)eradication rates have fallen globally,likely in large part due to increasing antibiotic resistance to traditional therapy.In areas of high clarithrom.cin and m.tronidazole resistance such as ours,m.astricht VI guidelines suggest high dose am.xicillin dual therapy(HDADT)can be considered,subject to evidence for local efficacy.In this study we assess efficacy of HDADT therapy for H.pylori eradication in an Irish cohort.AIm.To assess the efficacy of HDADT therapy for H.pylori eradication in an Irish cohort as both first line,and subsequent therapy for patients diagnosed with H.pylori.m.THODS All patients testing positive for H.pylori in a tertiary centre were treated prospectively with HDADT(am.xicillin 1 g tid and esom.prazole 40 m. bid×14 d)over a period of 8 m.nths.Eradication was confirm.d with Urea Breath Test at least 4 wk after cessation of therapy.A delta-over-baseline>4%was considered positive.Patient dem.graphics and treatm.nt outcom.s were recorded,analysed and controlled for basic dem.graphics and prior H.pylori treatm.nt.RESULTS One hundred and ninety-eight patients were identified with H.pylori infection,10 patients were excluded due to penicillin allergy and 38 patients refused follow up testing.In all 139 were included in the analysis,55%(n=76)were fem.le,m.an age was 46.6 years.Overall,93(67%)of patients were treatm.nt-naïve and 46(33%)had received at least one previous course of treatm.nt.The groups were statistically sim.lar.Self-reported com.liance with HDADT was 97%,m.ld side-effects occurred in 7%.There were no serious adverse drug reactions.Overall the eradication rate for our cohort was 56%(78/139).Eradication rates were worse for those with previous treatm.nt[43%(20/46)vs 62%(58/93),P=0.0458,odds ratio=2.15].Age and Gender had no effect on eradication status.CONCLUSION Overall eradication rates with HDADT were disappointing.Despite being a sim.le and possibly better tolerated regim.,these results do not support its routine use in a high dual resistanc

关键词： Helicobacter pylori eradication Helicobacter pylori High dose am.xicillin High dose am.xicillin dual therapy Triple therapy

Integrative m.lti-om.cs and system. bioinform.tics in translational neuroscience:A data m.ning perspective

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药物分析学报:英文版 2023年第8期13卷 836-850页

作者： Lance m.O'connor Blake A.O'connor Su Bin Lim.Jialiu Zeng Chih Hung Lo College of Biological Sciences University of MinnesotaMinneapolisMN55455USA School of Pharm.cy University of WisconsinMadisonWI53705USA Departm.nt of Biochem.stry and m.lecular Biology Ajou University School of MedicineSuwon16499South Korea Lee Kong Chian School of m.dicine Nanyang Technological UniversitySingapore308232Singapore

Bioinform.tic analysis of large and com.lex om.cs datasets has becom. increasingly useful in m.dern day biology by providing a great depth of inform.tion,with its application to neuroscience term.d neuroinform.tics.Data m.ning of om.cs datasets has enabled the generation of new hypotheses based on differentially regulated biological m.lecules associated with disease m.chanism.,which can be tested experim.ntally for im.roved diagnostic and therapeutic targeting of neurodegenerative diseases.Im.ortantly,integrating m.lti-om.cs data using a system. bioinform.tics approach will advance the understanding of the layered and interactive network of biological regulation that exchanges system.c knowledge to facilitate the developm.nt of a com.rehensive hum.n brain profile.In this review,we first sum.arize data m.ning studies utilizing datasets from.the individual type of om.cs analysis,including epigenetics/epigenom.cs,transcriptom.cs,proteom.cs,m.tabolom.cs,lipidom.cs,and spatial om.cs,pertaining to Alzheim.r's disease,Parkinson's disease,and m.ltiple sclerosis.We then discuss m.lti-om.cs integration approaches,including independent biological integration and unsupervised integration m.thods,for m.re intuitive and inform.tive interpretation of the biological data obtained across different om.cs layers.We further assess studies that integrate m.lti-om.cs in data m.ning which provide convoluted biological insights and offer proof-of-concept proposition towards system. bioinform.tics in the reconstruction of brain networks.Finally,we recom.end a com.ination of high dim.nsional bioinform.tics analysis with experim.ntal validation to achieve translational neuroscience applications including biom.rker discovery,therapeutic developm.nt,and elucidation of disease m.chanism..We conclude by providing future perspectives and opportunities in applying integrative m.lti-om.cs and system. bioinform.tics to achieve precision phenotyping of neurodegenerative diseases and towards personalized m.dicine.

关键词： m.lti-om.cs integration System. bioinform.tics Data m.ning Hum.n brain profile reconstruction Translational neuroscience

The Soft X-ray Im.ger(SXI)on the Sm.LE m.ssion

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Earth and Planetary Physics 2024年第1期8卷 5-14页

作者： S.Sem.ay A.L.Alm. D.Agnolon T.Arnold A.Beardm.re A.Belén Balado m.rgeli C.Bicknell C.Bouldin G.Branduardi-Raym.nt T.Crawford J.P.Breuer T.Buggey G.Butcher R.Canchal J.A.Carter A.Cheney Y.Collado-Vega H.connor T.Crawford N.Eaton C.Feldm.n C.Forsyth T.Frantzen G.Galgóczi J.Garcia G.Y.Genov C.Gordillo H-P.Gröbelbauer m.Guedel Y.Guo m.Hailey D.Hall R.Ham.son J.Hasiba O.Hetherington A.Holland S-Y.Hsieh m.W.J.Hubbard H.Jeszenszky m.Jones T.Kennedy K.Koch-m.hrin S.Kögl S.Krucker K.D.Kuntz C.Lakin G.Laky O.Lylund A.m.rtindale J.m.guel m.s Hesse R.Nakam.ra K.Oksavik N.Østgaard H.Ottacher R.Ottensam.r C.Pagani S.Parsons P.Patel J.Pearson G.Peikert F.S.Porter T.Pouliantis B.H.Qureshi W.Raab G.Randal A.m.Read N.m.m.Roque m.E.Rostad C.Runcim.n S.Sachdev A.Sam.onov m.Som.n D.Sibeck S.Sm.t J.Søndergaard R.Speight S.Stavland m.Steller TianRan Sun J.Thornhill W.Thom.s K.Ullaland B.Walsh D.Walton C.Wang S.Yang School of Physics and Astronom. University of LeicesterLeicesterLE17RHUK Space Park Leicester University of LeicesterLeicesterLE17RHUK m.llard Space Science Laboratory University College LondonDorkingRH56NTUK Centre for Electronic Im.ging Open UniversityMilton KeynesMK76 AAUK Birkeland Centre for Space Science Department of Physics and TechnologyUniv.of BergenN-5007 BergenNorway University of Vienna A-1010 ViennaAustria Space Research Institute Austrian Academy of SciencesA-8042 GrazAustria National Institute of Aerospace Technology MadridSpain ESTEC European Space Agency2201 AZ NoordwijkNetherlands State Key Laboratory of Space Weather National Space Science CentreBeijing 100190China University of Applied Sciences and Arts Northwestern Switzerland CH-5210 WindischSwitzerland Koegl Space Gm.H CH-8157 DielsdorfSwitzerland Space Acoustics Gm.H CH-8157 DielsdorfSwitzerland Zurich University of Applied Sciences 8400 WinterhurSwitzerland Genov Solutions N-5172 LoddefjordNorway STm.Engineering N-5165 LaksevagNorway John Hopkins University Applied Physics Laboratory MD 20723USA NASA/Goddard Space Flight Centre MD 20771USA Center for Space Physics Boston UniversityBostonMA 02215USA Departm.nt of Theoretical Physics and Astrophysics Masaryk University60177 BrnoCzech Republic Institute of Physics E¨otvo¨s Lor´and University1053 BudapestHungary Aerospace Inform.tion Research Institute Chinese Academy of SciencesBeijing 100045China Centro de Astrobiologia(CAB) CSIC-INTAMadridSpain

The Soft X-ray Im.ger(SXI)is part of the scientific payload of the Solar wind m.gnetosphere Ionosphere Link Explorer(Sm.LE)m.ssion.Sm.LE is a joint science m.ssion between the European Space Agency(ESA)and the Chinese Academ. of Sciences(CAS)and is due for launch in 2025.SXI is a com.act X-ray telescope with a wide field-of-view(FOV)capable of encom.assing large portions of Earth’s m.gnetosphere from.the vantage point of the Sm.LE orbit.SXI is sensitive to the soft X-rays produced by the Solar Wind Charge eXchange(SWCX)process produced when heavy ions of solar wind origin interact with neutral particles in Earth’s exosphere.SWCX provides a m.chanism.for boundary detection within the m.gnetosphere,such as the position of Earth’s m.gnetopause,because the solar wind heavy ions have a very low density in regions of closed m.gnetic field lines.The sensitivity of the SXI is such that it can potentially track m.vem.nts of the m.gnetopause on tim.scales of a few m.nutes and the orbit of Sm.LE will enable such m.vem.nts to be tracked for segm.nts lasting m.ny hours.SXI is led by the University of Leicester in the United Kingdom.UK)with collaborating organisations on hardware,software and science support within the UK,Europe,China and the United States.

关键词： Soft X-ray Im.ging m.cropore optics large area CCD

m.nagem.nt of non-ST-segm.nt elevation m.ocardial in-farction in patients aged≥80 years:a m.ta-analysis of ran-dom.zed controlled trials

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Journal of Geriatric Cardiology 2022年第10期19卷 789-790页

作者： connor J m.tthews Joshua Kirby Jonathan m.Blaxill John P Greenwood Abdul m.m.zid Jennifer A Rossington m.rugapathy Veerasam. Nancy Wassef Stephen B Wheatcroft Heerajnarain Bulluck Yorkshire Heart Centre Leeds General InfirmaryLeeds Teaching Hospitals NHS TrustLeedsUnited Kingdom Leeds Institute of Cardiovascular and m.tabolic m.dicine University of LeedsLeedsUnited Kingdom

Coronary artery disease(CAD)is the m.jor cause of m.rbidity and m.rtality in elderly patients.^([1])Despite this,elderly patients are under-represented in m.st trials of CAD.Non-ST-segm.nt elevation m.ocardial infarction(NSTEm.)is a com.on cause of hospitalization am.ng patients≥80 years of age,^([2])and with an aging global population,there is a pressing need to establish the optim.l m.nagem.nt strategy for these patients.Therefore,we conducted a m.ta-analysis of all random.zed control trials(RCTs)perform.d to date in patients≥80 years of age,com.aring an initial invasive versus conservative strategy to provide insights into their optim.l initial m.nagem.nt strategy.

关键词： patients m.rtality analysis

Evolution and distribution of m.dullary bone: evidence from.a new Early Cretaceous enantiornithine bird

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National Science Review 2020年第6期7卷 1068-1078页

作者： m.n Wang Jingm.i K.O'connor Alida m.Bailleul Zhiheng Li Key Laboratory of Vertebrate Evolution and Hum.n Origins Institute of Vertebrate Paleontology and Paleoanthropology Chinese Academy of Sciences CAS Center for Excellence in Life and Paleoenvironm.nt

Living birds are unique am.ng vertebrates in the form.tion of a fem.le-specific bone tissue called m.dullary bone(m.) that is strictly associated with reproductive activity. m. is a rapidly m.bilized source of calcium.and phosphorus for the production of eggshell. Am.ng living taxa, its skeletal distribution can be highly extensive such that it even exists in the ribs of som. species. Due to its ephem.ral nature, m. is rarely fossilized and so little is understood with regard to the origin of m. and its skeletal distribution in early taxa.Here we describe a new Early Cretaceous enantiornithine bird, m.rusavis parvus, gen. et. sp. nov., indicating that skeleton-wide distribution of m. appeared early in avian evolution. We suggest that this represents the plesiom.rphic condition for the Aves and that the distribution of m. observed am.ng extant neornithines is a product of increased pneum.tization in this lineage and natural selection for m.re efficient distribution of m..

关键词： Aves Cretaceous m.dullary bone phylogeny reproduction