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On the apparent line-of-sight alignment of the peak X-ray intensity of the magnetosheath and the tangent to the magnetopause,as viewed by SMILE-SXI

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Earth and Planetary Physics 2024年第1期8卷 155-172页

作者： andrew Read Department of Physics&Astronomy University of LeicesterLeicesterLE17RHUK

The Soft X-ray Imager(SXI)on board the Solar wind Magnetosphere Ionosphere Link Explorer(SMILE)spacecraft will be able to view the Earth’s magnetosheath in soft *** images of the X-ray emission visible from the position of SMILE are created for a range of solar wind densities by using 3 years of the SMILE mission orbit,together with models of the expected X-ray emissivity from the Earth’s *** from global magnetohydrodynamic simulations and a simple model for exospheric neutral densities are used to compare the locations of the lines of sight along which integrated soft X-ray intensities peak with the lines of sight lying tangent to surfaces(defined here to be the magnetopause)along which local soft X-ray intensities peak or exhibit their strongest gradients,or both,for strongly southward interplanetary magnetic field conditions when no depletion or low-latitude boundary layers are ***,in the parameter space of the various times and seasons,orbital phases,solar wind conditions,and magnetopause models,the alignment of the X-ray emission peak with the magnetopause tangent is good,or is not,is *** main results are as *** spacecraft needs to be positioned well outside the magnetopause;low-altitude times near perigee are not *** addition,there are seasonal aspects:dayside-apogee orbits are generally very good because the spacecraft travels out sunward at high altitude,but nightside-apogee orbits,behind the Earth,are bad because the spacecraft only rarely leaves the ***-apogee and dawnapogee orbits are ***-apogee orbits worsen slightly over the first three mission years,whereas nightside-apogee orbits improve ***,many more times of good agreement with the peak-to-tangent hypothesis occur when the solar wind is in a high-density state,as opposed to a low-density *** a high-density state,the magnetopause is compressed,and the spacecraft is more often a good d

关键词： X-rays magnetosphere magnetosheath magnetopause Solar wind Magnetosphere Ionosphere Link Explorer(SMILE) Earth solar wind charge exchange

Automated Machine Learning Algorithm Using Recurrent Neural Network to Perform Long-Term Time Series Forecasting

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Computers, Materials & Continua 2024年第3期78卷 3529-3549页

作者： Ying Su morgan C.Wang Shuai Liu Department of Statistics and Data Science University of Central FloridaOrlandoFL32816-2370USA School of Mathematics and Statistics Beijing Technology and Business UniversityBeijing100048China

Long-term time series forecasting stands as a crucial research domain within the realm of automated machine learning(AutoML).At present,forecasting,whether rooted in machine learning or statistical learning,typically relies on expert input and necessitates substantial manual *** manual effort spans model development,feature engineering,hyper-parameter tuning,and the intricate construction of time series *** complexity of these tasks renders complete automation unfeasible,as they inherently demand human intervention at multiple *** surmount these challenges,this article proposes leveraging Long Short-Term Memory,which is the variant of Recurrent Neural Networks,harnessing memory cells and gating mechanisms to facilitate long-term time series ***,forecasting accuracy by particular neural network and traditional models can degrade significantly,when addressing long-term time-series ***,our research demonstrates that this innovative approach outperforms the traditional Autoregressive Integrated Moving Average(ARIMA)method in forecasting long-term univariate time *** is a high-quality and competitive model in time series prediction,and yet it requires significant preprocessing *** multiple accuracy metrics,we have evaluated both ARIMA and proposed method on the simulated time-series data and real data in both short and long ***,our findings indicate its superiority over alternative network architectures,including Fully Connected Neural Networks,Convolutional Neural Networks,and Nonpooling Convolutional Neural *** AutoML approach enables non-professional to attain highly accurate and effective time series forecasting,and can be widely applied to various domains,particularly in business and finance.

关键词： Automated machine learning autoregressive integrated moving average neural networks time series analysis

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Prognosis of operated hepatocellular carcinoma developed on non-cirrhotic liver

作者： (美)安德鲁·摩根(andrew morgan)[等]

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Hepatobiliary Surgery and Nutrition 2024年第4期13卷 736-738页

作者： morgan Vandermeulen Maxime Dewulf Olivier Detry Department of Visceral Surgery and Transplantation CHU LiegeLiegeBelgium Centre de Recherche et d’Enseignement du Département de Chirurgie(CREDEC) GIGA MetabolismUniversity of LiegeLiegeBelgium Department of Surgery Maastricht University Medical Center(MUMC+)MaastrichtThe Netherlands

The incidence of primary liver cancers,and particularly hepatocellular carcinoma(HCC),is increasing throughout the *** vast majority of HCCs develop on cirrhotic livers(CLs)(CL HCC)or livers chronically infected by hepatotropic viruses,mainly hepatitis B virus(HBV)and hepatitis C virus(HCV)(1).As HCC occurring on non-HBV non-HCV non-CL(NCL)HCC occurs much less frequently,its management is less established than for CL ***,many clinicians might confuse the prognosis and management of NCL HCC with the one of CL *** is however demonstrated that NCL HCCs behave differently than CL *** prognostic factors and sensibility to systemic therapy are different,added to the fact that NCLs can undergo major resections allowing curative surgical management or even systemic therapies that are not even possible in CL HCCs due to the failing function of the *** established criteria for liver transplantation of CL HCCs,including the famous Milan criteria,have no role in NCL HCC management(2-4).The Barcelona Clinic Liver Cancer(BCLC)strategy for prognosis prediction and treatment recommendation also concerns only CL HCCs;and should not be used for NCL HCCs(5).

关键词： Cancer surgery transplantation recurrence

Mshpy23:a user-friendly,parameterized model of magnetosheath conditions

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Earth and Planetary Physics 2024年第1期8卷 89-104页

作者： Jaewoong Jung Hyunju Connor andrew Dimmock Steve Sembay andrew Read Jan Soucek NASA Goddard Space Flight Center GreenbeltMDUSA Department of Astronomy University of MarylandCollege ParkMDUSA Swedish Institude of Space Physics UppsalaSweden University of Leicester LeicesterUK Institute of Atmospheric Physics Academy of Sciences of the Czech Republic

Lunar Environment heliospheric X-ray Imager(LEXI)and Solar wind−Magnetosphere−Ionosphere Link Explorer(SMILE)will observe magnetosheath and its boundary motion in soft X-rays for understanding magnetopause reconnection modes under various solar wind conditions after their respective launches in 2024 and *** conditions,namely,plasma density,velocity,and temperature,are key parameters for predicting and analyzing soft X-ray images from the LEXI and SMILE *** developed a userfriendly model of magnetosheath that parameterizes number density,velocity,temperature,and magnetic field by utilizing the global Magnetohydrodynamics(MHD)model as well as the pre-existing gas-dynamic and analytic *** this parameterized magnetosheath model,scientists can easily reconstruct expected soft X-ray images and utilize them for analysis of observed images of LEXI and SMILE without simulating the complicated global magnetosphere ***,we created an MHD-based magnetosheath model by running a total of 14 OpenGGCM global MHD simulations under 7 solar wind densities(1,5,10,15,20,25,and 30 cm)and 2 interplanetary magnetic field Bz components(±4 nT),and then parameterizing the results in new magnetosheath *** compared the magnetosheath model result with THEMIS statistical data and it showed good agreement with a weighted Pearson correlation coefficient greater than 0.77,especially for plasma density and plasma ***,we compiled a suite of magnetosheath models incorporating previous magnetosheath models(gas-dynamic,analytic),and did two case studies to test the *** MHD-based model was comparable to or better than the previous models while providing self-consistency among the magnetosheath ***,we constructed a tool to calculate a soft X-ray image from any given vantage point,which can support the planning and data analysis of the aforementioned LEXI and SMILE missions.A release of the code has been uploaded to a Git

关键词： magnetosheath python modeling

Controlling the hidden parity in vectorial light with metasurfaces

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Advanced Photonics 2024年第4期6卷 5-6页

作者： Cade Peters andrew Forbes University of the Witwatersrand School of PhysicsJohannesburgSouth Africa

Identifying and controlling new degrees of freedom in structured light has exploded of late.1One such form of structured light is vectorial beams with spatially inhomogeneous polarization structures,already having fou... 详细信息

关键词： light parity inhomogeneous

Rational Schur Superalgebras

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Algebra Colloquium 2024年第2期31卷 209-220页

作者： andrew Riesen Shun-Jen Cheng Department of Mathematical and Statistical Sciences University of Alberta 1132489 Ave NWEdmontonAlbertaCanada 不详

We develop and study the generalization of rational Schur algebras to the super *** to the classical case,this provides a new method for studying rational supermodules of the general linear supergroup GL(m|n).Furthermore,we establish a Schur-Weyl duality result for rational Schur superalgebras and conclude that under certain conditions these objects will be semisimple.

关键词： Schur algebra supermathematics general linear supergroup

Palladium-catalyzed S_(N)2 glycosylation of phenols

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Science China Chemistry 2024年第4期67卷 1037-1038页

作者： Yu Zhu P.andrew Evans Department of Chemistry Queen’s University90 Bader LaneKingstonK7L 3N6Canada Xiangya School of Pharmaceutical Sciences Central South UniversityChangsha 410013China

Glycosides are essential structural motifs present in an array of important medicines,materials,and natural products[1].Nevertheless,the chemo-and stereoselective construction of the glycosidic linkage is a long-standing challenge because relatively minor variations in the glycosyl donor or acceptor’s structure can impact stereoselectivity,thus influencing the product's functional properties.

关键词： properties Palladium catalyzed

Multidimensional images and aberrations in STEM

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Chinese Physics B 2024年第9期33卷 68-74页

作者： Eric R.Hoglund andrew R.Lupini Center for Nanophase Materials Sciences Oak Ridge National LaboratoryOak RidgeTN 37831United States

Recent advances in scanning transmission electron microscopy(STEM)have led to increased development of multidimensional STEM imaging modalities and novel image reconstruction *** interest arises because the main electron lens in a modern transmission electron microscope usually has a diffraction-space information limit that is significantly better than the real-space resolution of the same *** state-of-affairs is sometimes shared by other scattering methods in modern physics and contributes to a broader excitement surrounding multidimensional techniques that scan a probe while recording diffraction-space images,such as ptychography and scanning nano-beam ***,the contrasting resolution in the two spaces raises the question as to what is limiting their effective ***,we examine this paradox by considering the effects of aberrations in both image and diffraction planes,and likewise separate the contributions of pre-and post-sample *** consideration provides insight into aberration-measurement techniques and might also indicate improvements for super-resolution techniques.

关键词： scanning transmission electron microscopy (STEM) aberrations