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Hybrid-Vlasov simulation of soft X-ray emissions at the Earth’s dayside magnetospheric 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-Kempf U.Ganse K.Papadakis m.Palmroth Department of Physics University of HelsinkiHelsinkiFinland NASA Goddard Space Flight Center GreenbeltMD20771USA Space and Earth Observation Centre Finnish Meteorological InstituteHelsinkiFinland

Solar wind charge exchange produces emissions in the soft X-ray energy range which can enable the study of near-Earth space regions such as the magnetopause,the magnetosheath and the polar cusps by remote sensing *** Solar wind magnetosphere Ionosphere Link Explorer(SmILE)and Lunar Environment heliospheric X-ray Imager(LEXI)missions aim to obtain soft Xray images of near-Earth space thanks to their Soft X-ray Imager(SXI)*** earlier modeling works have already simulated soft X-ray images as might be obtained by SmILE SXI during its mission,the numerical models used so far are all based on the magnetohydrodynamics description of the space *** investigate the possible signatures of ion-kinetic-scale processes in soft Xray images,we use for the first time a global hybrid-Vlasov simulation of the geospace from the Vlasiator *** simulation is driven by fast and tenuous solar wind conditions and purely southward interplanetary magnetic *** first produce global X-ray images of the dayside near-Earth space by placing a virtual imaging satellite at two different locations,providing meridional and equatorial *** then analyze regional features present in the images and show that they correspond to signatures in soft X-ray emissions of mirrormode wave structures in the magnetosheath and flux transfer events(FTEs)at the *** results suggest that,although the time scales associated with the motion of those transient phenomena will likely be significantly smaller than the integration time of the SmILE and LEXI imagers,mirror-mode structures and FTEs can cumulatively produce detectable signatures in the soft X-ray *** instance,a local increase by 30%in the proton density at the dayside magnetopause resulting from the transit of multiple FTEs leads to a 12%enhancement in the line-of-sight-and time-integrated soft X-ray emissivity originating from this ***,a proton density increase by 14%in the magnetosheath

关键词： magnetosphere magnetosheath numerical simulation SmILE LEXI soft X-ray emissions hybrid-Vlasov model polar cusp flux transfer events mirror-mode waves

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 *** 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 *** 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 *** 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 ***-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 *** 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 *** 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 *** results show that 3-D estimations using the described statistically-based technique are robust against Poisson-distributed shot noise inherent to soft X-ray ***,our proposed methodology shows that the accuracy of both three-dimensional(3-D)estimation and the magnetopause standoff distance calculation hi

关键词： magnetopause soft X-ray tomography

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 *** 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 *** 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 *** 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 *** 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 *** 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 *** 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 *** method estimates RS with an accuracy of10 *** accuracy improves for greater solar wind densities and during southward interplanetary magnetic *** method ca ptures the magnetopause motion during southwa rd interplaneta ry magnetic field ***,the technique will enable quantitative analysis of the magnetopause motion and help reveal the daysi

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

Steroidal scaffold decorations in Solanum alkaloid biosynthesis

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molecular Plant 2024年第8期17卷 1236-1254页

作者： Rosalind Lucier mohamed O.Kamileen Yoko Nakamura Sofiia Serediuk Ranjit Barbole Jens Wurlitzer maritta Kunert Sarah Heinicke Sarah E.O'connor Prashant D.Sonawane Department of Natural Product Biosynthesis Max Planck Institute for Chemical Ecology07745 JenaGermany Research Group Biosynthesis and NmR Max Planck Institute for Chemical Ecology07745 JenaGermany Biochemical Sciences Division CSIR-National Chemical LaboratoryPune 411008MaharashtraIndia

Steroidal glycoalkaloids(SGAs)are specialized metabolites produced by hundreds of Solanum species,including important vegetable crops such as tomato,potato,and *** it has been known that SGAs play important roles in defense in plants and“anti-nutritional"effects(e.g.,toxicity and bitterness)to humans,many of these molecules have documented anti-cancer,anti-microbial,antiinflammatory,anti-viral,and anti-pyretic *** these,α-solasonine andα-solamargine isolated from black nightshade(Solanum nigrum)are reported to have potent anti-tumor,anti-proliferative,and anti-inflammatory ***,α-solasonine andα-solamargine,along with the core steroidal aglycone solasodine,are the most widespread SGAs produced among the Solanum ***,it is still unknown how plants synthesize these bioactive steroidal *** comparative metabolomictranscriptome-guided approach,biosynthetic logic,combinatorial expression in Nicotiana benthamiana,and functional recombinant enzyme assays,here we report the discovery of 12 enzymes from *** that converts the starting cholesterol precursorto solasodine aglycone,and the downstreamα-solasonine,α-solamargine,and malonyl-solamargine SGA *** further identified six enzymes from cultivated eggplant that catalyze the production ofα-solasonine,α-solamargine,and malonyl-solamargine SGAs from solasodine aglycone via glycosylation and atypical malonylation *** work provides the gene tool box and platform for engineering the production of high-value,steroidal bioactive molecules inheterologoushosts usingsyntheticbiology.

关键词： steroidal glycoalkaloids Solanum biosynthetic pathway α-solamargine malonyl-solamargine specialized metabolites

mDGA2 Constrains Glutamatergic Inputs Selectively onto CA1 Pyramidal Neurons to Optimize Neural Circuits for Plasticity,memory,and Social Behavior

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Neuroscience Bulletin 2024年第7期40卷 887-904页

作者： Xuehui Wang Donghui Lin Jie Jiang Yuhua Liu Xinyan Dong Jianchen Fan Lifen Gong Weida Shen Linghui Zeng Tonghui Xu Kewen Jiang Steven A.connor Yicheng Xie School of Life Sciences Nanchang UniversityNanchang330031China Department of Neurology Children's HospitalZhejiang University School of MedicineNational Clinical Research Center for Child HealthHangzhou 310052China Department of Biology York University4700 Keele StreetTorontoON M3J 1P3Canada Key Laboratory of Novel Targets and Drug Study for Neural Repair of Zhejiang Province School of MedicineHangzhou City UniversityHangzhou 310015China

Synapse organizers are essential for the development,transmission,and plasticity of *** as rare synapse suppressors,the mAm domain containing glycosylphosphatidylinositol anchor(mDGA)proteins contributes to synapse organization by inhibiting the formation of the synaptogenic neuroligin-neurexin complex.A previous analysis of mDGA2 mice lacking a single copy of mdga2 revealed upregulated glutamatergic synapses and behaviors consistent with ***,mDGA2 is expressed in diverse cell types and is localized to both excitatory and inhibitory *** the network versus cell-specific effects of mDGA2 loss-of-function requires a cell-type and brain region-selective *** address this,we generated mice harboring a conditional knockout of mdga2 restricted to CA1 pyramidal *** we report that mDGA2 suppresses the density and function of excitatory synapses selectively on pyramidal neurons in the mature *** deletion of mdga2 in CA1 pyramidal neurons of adult mice upregulated miniature and spontaneous excitatory postsynaptic potentials,vesicular glutamate transporter 1 intensity,and neuronal *** effects were limited to glutamatergic synapses as no changes were detected in miniature and spontaneous inhibitory postsynaptic potential properties or vesicular GABA transporter ***,evoked basal synaptic transmission and AmPAR receptor currents were enhanced at glutamatergic *** a behavioral level,memory appeared to be compromised in mdga2 cKO mice as both novel object recognition and contextual fear conditioning performance were impaired,consistent with deficits in long-term potentiation in the CA3-CA1 *** affiliation,a behavioral analog of social deficits in autism,was similarly *** results demonstrate that mDGA2 confines the properties of excitatory synapses to CA1 neurons in mature hippocampal circuits,thereby optimizing this network for plasticity,c

关键词： mDGA2 CA1 pyramidal neurons Glutamatergic inputs Synaptic plasticity memory Social behaviors Autism Synapse organizers

Detailed characterization of kHz-rate laser-driven fusion at a thin liquid sheet with a neutron detection suite

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

作者： Benjamin m.Knight connor m.Gautam Colton R.Stoner Bryan V.Egner Joseph R.Smith Chris m.Orban Juan J.manfredi Kyle D.Frische michael L.Dexter Enam A.Chowdhury Anil K.Patnaik Department of Engineering Physics Air Force Institute of TechnologyWPAFBOHUSA Physics Department Marietta CollegeMariettaOHUSA Department of Physics The Ohio State UniversityColumbusOHUSA Department of materials 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 mJ, 40 fs laser pulses on a thin(<1 μm) D_2O liquid sheet employing a measurement suite. At relativistic inte... 详细信息

We present detailed characterization of laser-driven fusion and neutron production(-10^(5)/second) using 8 mJ, 40 fs laser pulses on a thin(m) D_2O liquid sheet employing a measurement 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 measurement suite with three independent detection systems: an EJ-309 organic scintillator with pulse-shape discrimination, a ~3He proportional counter and a set of 36 bubble detectors. Time-of-flight analysis of the scintillator data shows the energy of the produced neutrons to be consistent with 2.45 meV. Particle-in-cell simulations 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-demand test bed for radiation hardening and imaging applications.

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

Use of the area of main influence to fix a relevant boundary for mining damages in Germany

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International Journal of mining Science and Technology 2018年第1期28卷 79-83页

作者： denise müller Axel Preusse Faculty of Georesources and materials Engineering Institute for Mine Surveying Mining Subsidence Engineering and Geophysics in Mining RWTH Aachen University

In 2010, the fracking discussion in Germany caused a number of changes in German law, which came into force in *** the production of gas had to be *** the legislation amendment, the Subsidence-Area mining Regulation has been revised, *** changes expand the compensation of mining damages, especially to the extraction with drilling from the surface and underground *** the Subsidence-Area mining Regulation has been revised, the area of main influence(subsidence of 10 cm)remains to determine a relevant boundary for mining *** determination and prediction of this boundary above caverns are presented in this *** addition, further elements of ground movements and their relevance to mine damages are *** usage of the area of main influence to fix a relevant boundary for mining damages does not correspond to the relevant elements of ground movements.A limit for differences in subsidence(tilt) or horizontal changes in length should be preferred to describe the relevance of mining damages on ***, this paper outlines the meaning of using the area of main influence to fix a relevant boundary for mining damages.

关键词： Ground movements Area of main influence Boundary for mining damages Subsidence-area mining regulation Subsidence detection modeling above caverns

Helicobacter pylori:High dose amoxicillin does not improve primary 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 Thomas Butler Stephen molloy Fintan John O'Hara Barbara Ryan Niall Breslin Sarah O'Donnell Anthony O'connor Sinead Smith Deirdre mcNamara Trinity Academic Gastroenterology Group School of Medicine-Trinity College DublinDublin D2Ireland Department of Gastroenterology Tallaght University HospitalDublin D24 NR0AIreland

BACKGROUND Helicobacter pylori(***)eradication rates have fallen globally,likely in large part due to increasing antibiotic resistance to traditional *** areas of high clarithromycin and metronidazole resistance such as ours,maastricht VI guidelines suggest high dose amoxicillin dual therapy(HDADT)can be considered,subject to evidence for local *** this study we assess efficacy of HDADT therapy for *** eradication in an Irish *** To assess the efficacy of HDADT therapy for *** eradication in an Irish cohort as both first line,and subsequent therapy for patients diagnosed with *** All patients testing positive for *** in a tertiary centre were treated prospectively with HDADT(amoxicillin 1 g tid and esomeprazole 40 mg bid×14 d)over a period of 8 *** was confirmed with Urea Breath Test at least 4 wk after cessation of therapy.A delta-over-baseline>4%was considered *** demographics and treatment outcomes were recorded,analysed and controlled for basic demographics and prior *** *** One hundred and ninety-eight patients were identified with *** infection,10 patients were excluded due to penicillin allergy and 38 patients refused follow up *** all 139 were included in the analysis,55%(n=76)were female,mean age was 46.6 ***,93(67%)of patients were treatment-naïve and 46(33%)had received at least one previous course of *** groups were statistically ***-reported compliance with HDADT was 97%,mild side-effects occurred in 7%.There were no serious adverse drug *** the eradication rate for our cohort was 56%(78/139).Eradication rates were worse for those with previous treatment[43%(20/46)vs 62%(58/93),P=0.0458,odds ratio=2.15].Age and Gender had no effect on eradication *** Overall eradication rates with HDADT were *** being a simple and possibly better tolerated regime,these results do not

关键词： Helicobacter pylori eradication Helicobacter pylori High dose amoxicillin High dose amoxicillin dual therapy Triple therapy

Targeted therapy for capillary-venous malformations

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Signal Transduction and Targeted Therapy 2024年第7期9卷 3024-3039页

作者： Lola Zerbib Sophia Ladraa Antoine Fraissenon Charles Bayard marina Firpion Quitterie Venot Sanela Protic Clément Hoguin Amandine Thomas Sylvie Fraitag Jean-Paul Duong Sophie Kaltenbach Estelle Balducci Coline Lefevre Patrick Villarese Vahid Asnafi Christine Broissand Nicolas Goudin Ivan Nemazanyy Gwennhael Autret Bertrand Tavitian Christophe Legendre Nadia Arzouk Veronique minard-Colin Caroline Chopinet michael Dussiot denise mAdams Tristan mirault Laurent Guibaud Paul Isenring Guillaume Canaud UniversitéParis Cité ParisFrance INSERm U1151 Institut Necker-Enfants MaladesParisFrance Service d’Imagerie Pédiatrique Hôpital Femme-Mère-EnfantHCLBronFrance CREATIS UmR 5220 Villeurbanne 69100France Service de Radiologie mère-Enfant Hôpital NordSaint EtienneFrance Service d’Anatomie pathologique Hôpital Necker-Enfants MaladesAP-HPParisFrance Laboratoire d’Oncohématologie Hôpital Necker-Enfants MaladesAP-HPParisFrance Pharmacie Hôpital Necker-Enfants MaladesAP-HPParisFrance Necker Bio-Image Analysis INSERM US24/CNRS UMS 3633ParisFrance Platform for metabolic Analyses Structure Fédérative de Recherche NeckerINSERM US24/CNRS UMS 3633ParisFrance Plateforme Imageries du Vivant Universitéde ParisPARCCINSERMParisFrance Service de Néphrologie Transplantation AdultesHôpital Necker-Enfants MaladesAP-HPParisFrance Service de Transplantation Hôpital La PitiéSalpétrièreAP-HPParisFrance Department of Pediatric and Adolescent Oncology INSERM 1015Gustave RoussyUniversitéParis-SaclayVillejuifFrance Service de Physiologie&Explorations Fonctionnelles Cardiovasculaires CHU de LilleLille 59000France INSERm U1163 Laboratory of Cellular and Molecular Mechanisms of Hematological Disorders and Therapeutic ImplicationsLaboratoire d’Excellence GR-ExParisFrance Division of Oncology Comprehensive Vascular Anomalies ProgramChildren’s Hospital of PhiladelphiaPhiladelphiaPAUSA Service de médecine Vasculaire hôpital Européen Georges-PompidouParisFrance Nephrology Research Group L’Hôtel-Dieu de Québec Research CenterDepartment of MedicineFaculty of MedicineLaval UniversityQuebecQC G1R2J6Canada Unitéde médecine translationnelle et thérapies ciblées Hôpital Necker-Enfants MaladesAP-HPParisFrance CNRS UmR8253 Institut Necker-Enfants MaladesParisFrance

Sporadic venous malformations are genetic conditions primarily caused by somatic gain-of-function mutation of PIK3CA or TEK,an endothelial transmembrane receptor signaling through *** malformations are associated with pain,bleedings,thrombosis,pulmonary embolism,esthetic deformities and,in severe cases,life-threatening *** authorized medical treatment exists for patients with venous ***,we created a genetic mouse model of PIK3CA-related capillary venous malformations that replicates patient *** showed that these malformations only partially signal through AKT *** compared the efficacy of different drugs,including rapamycin,a mTORC1 inhibitor,miransertib,an AKT inhibitor and alpelisib,a PI3Kαinhibitor at improving the lesions seen in the mouse *** demonstrated the effectiveness of alpelisib in preventing vascular malformations’occurrence,improving the already established ones,and prolonging *** these findings,we were authorized to treat 25 patients with alpelisib,including 7 children displaying PIK3CA(n=16)or TEK(n=9)-related capillary venous malformations resistant to usual therapies including sirolimus,debulking surgical procedures or percutaneous *** assessed the volume of vascular malformations using magnetic resonance imaging(mRI)for each *** demonstrated improvement in all 25 *** malformations previously considered intractable were reduced and clinical symptoms were *** showed a decrease of 33.4%and 27.8%in the median volume of PIK3CA and TEK malformations respectively,over 6 months on *** conclusion,this study supports PI3Kαinhibition as a promising therapeutic strategy in patients with PIK3CA or TEK-related capillary venous malformations.

关键词： PIK3CA malformations venous