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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 within 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 with tempe *** at the nominal ope rating tempe rature(-120℃) it is within 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 with 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

Amyotrophic lateral sclerosis as a synaptopathy

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Neural Regeneration Research 2019年第2期14卷 189-192页

作者： matthew j.Fogarty Department of Physiology and Biomedical Engineering Mayo Clinic School of Biomedical Sciences The University of Queensland

The synapse is an incredibly specialized structure that allows for the coordinated communication of information from one neuron to another. When assembled into circuits, steady streams of excitatory and inhibitory synaptic activity shape neural outputs. At the organismal level, ensembles of neural networks underlie behavior, emotion and memory. Disorder or dysfunctions of synapses, a synaptopathy, may underlie a host of developmental and degenerative neurological conditions. There is a possibility that amyotrophic lateral sclerosis may be a result of a synaptopathy within the neuromotor system. To this end, particular attention has been trained on the excitatory glutamatergic synapses and their morphological proxy, the dendritic spine. The extensive detailing of these dysfunctions in vulnerable neuronal populations, including corticospinal neurons and motor neurons, has recently been the subject of original research in rodents and humans. If amyotrophic lateral sclerosis is indeed a synaptopathy, it is entirely consistent with other proposed pathogenic mechanisms – including glutamate excitotoxicity, accumulation of misfolded proteins and mitochondrial dysfunction at distal axon terminals(cortico-motor neuron and neuromuscular). Further, although the exact mechanism of disease spread from region to region is unknown, the synaptopathy hypothesis is consistent with emerging die-forward evidence and the prion-like propagation of misfolded protein aggregates to distant neuronal populations. Here in this mini-review, we focus on the timeline of synaptic observations in both cortical and spinal neurons from different rodent models, and provide a conceptual framework for assessing the synaptopathy hypothesis in amyotrophic lateral sclerosis.

关键词： motor neuron motor cortex corticospinal excitotoxicity synaptic transmission dendrites dendriticspines neuromuscular junction

Current concepts in the management of non-cirrhotic non-malignant portal vein thrombosis

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World journal of Hepatology 2024年第5期16卷 751-765页

作者： Adam j Willington Dhiraj Tripathi Department of Hepatology University Hospitals Birmingham NHS Foundation TrustBirmingham B152GWUnited Kingdom Department of Hepatology University Hospitals BirminghamBirmingham B152THUnited Kingdom

Non-cirrhotic non-malignant portal vein thrombosis(NCPVT)is an uncommon condition characterised by thrombosis of the portal vein,with or without extension into other mesenteric veins,in the absence of cirrhosis or intra-abdominal *** can include intestinal infarction,variceal bleeding and portal *** this article,we address current concepts in the management of NCPVT including identification of risk factors,classification and treatment,and review the latest evidence on medical and interventional management options.

关键词： Non-cirrhotic portal vein thrombosis Portal vein Mesenteric veins Venous thrombosis Portal hypertension

Insm1:orchestrating cellular mimicry in the thymus medulla

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Cellular & Molecular Immunology 2024年第4期21卷 414-416页

作者： K.D.james j.E.Cowan UCL Institute of Immunity and Transplantation The Pears BuildingRowland Hill StreetLondonNW32PPUK

The thymus is the primary production site for a functional and self-tolerant T-cell *** establishment of immune tolerance is mediated by the generation and presentation of tissue-restricted self-antigens(TRAs)by medullary thymic epithelial cells(mTECs),which screen T-cell receptors for self-reactivity to eliminate autoreactive T *** studies have extended our understanding of mTEC heterogeneity by examining the mechanisms by which mTECs mimic the peripheral self[1].

关键词： medullary eliminate restricted

Single-atom Pt on carbon nanotubes for selective electrocatalysis

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Carbon Energy 2024年第1期6卷 63-71页

作者： Samuel S.Hardisty Xiaoqian Lin Anthony R.j.Kucernak David Zitoun Department of Chemistry Bar Ilan Institute of Nanotechnology and Advanced Materials(BINA)Bar Ilan UniversityRamat GanIsrael Department of Chemistry Molecular Science Research HubImperial College LondonLondonUK

Utilizing supported single atoms as catalysts presents an opportunity to reduce the usage of critical raw materials such as platinum,which are essential for electrochemical reactions such as hydrogen oxidation reaction(HOR).Herein,we describe the synthesis of a Pt single electrocatalyst inside single-walled carbon nanotubes(SWCNTs)via a redox *** via electron microscopy,X-ray photoelectron microscopy,and X-ray absorption spectroscopy show the single-atom nature of the *** electrochemical behavior of the sample to hydrogen and oxygen was investigated using the advanced floating electrode technique,which minimizes mass transport limitations and gives a thorough insight into the activity of the *** single-atom samples showed higher HOR activity than state-of-the-art 30%Pt/C while almost no oxygen reduction reaction activity in the proton exchange membrane fuel cell operating *** selective activity toward HOR arose as the main fingerprint of the catalyst confinement in the SWCNTs.

关键词： confinement electrocatalysis hydrogen platinum single atom catalysts

Atomistic Investigation of Shock-Induced Amorphization within Micro-shear Bands in Hexagonal Close-Packed Titanium

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Acta Metallurgica Sinica(English Letters) 2024年第9期37卷 1590-1600页

作者： Z.C.Meng K.G.Wang T.Ali D.Li C.G.Bai D.S.Xu S.j.Li A.H.Feng G.j.Cao j.H.Yao Q.B.Fan H.Wang R.Yang Institute of Metal Research Chinese Academy of SciencesShenyang 110016China School of Materials Science and Engineering University of Science and Technology of ChinaShenyang 110016China Interdisciplinary Centre for Additive Manufacturing(ICAM) School of Materials and ChemistryUniversity of Shanghai for Science and TechnologyShanghai 200093China School of Materials Science and Engineering Tongji UniversityShanghai 201804China Key Laboratory for Light-Weight Materials Nanjing Tech UniversityNanjing 210009China National Key Laboratory of Science and Technology on Materials Under Shock and Impact School of Materials Science and EngineeringBeijing Institute of TechnologyBeijing 100081China Beijing Institute of Technology Chongqing Innovation Center Chongqing 401135China

The mechanical response of a single crystal titanium sample against(0001)α surface impact was investigated using molecular dynamics ***,non-uniform plastic deformation was observed in the *** high strain rates,amorphization occurred near the edge of the contact region where severe shear strain induced a large number of stacking faults(SFs)and *** contrast,the central part of the contact region underwent less deformation with significantly fewer ***,instead of amorphization by consuming SFs and dislocations,there was a gradual increase in the density of dislocations and SFs during the process of *** local amorphous regions eventually grew into shear bands.

关键词： Shock compression Amorphization Shear band Titanium Molecular dynamics

Ecosystem Services of Grazed Grasslands in the Flooding Pampa

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Phyton-International journal of Experimental Botany 2024年第6期93卷 1179-1202页

作者： Elizabeth j.jacobo Adriana M.Rodríguez Facultad de Agronomía Área de AgroecologíaUniversidad de Buenos AiresBuenos Aires1417Argentina Facultad de Agronomía Departamento de Producción AnimalUniversidad de Buenos AiresBuenos Aires1417Argentina

The Flooding Pampa grasslands are the last remnant of the Rio de la Plata grasslands in ***-genic interventions have led to severe degradation and,as a result,the ecosystem services provided by the grass-lands are declining,in terms of provisioning,regulating,and supporting *** synthesized the existing literature on the ecosystem goods and services provided by these grasslands under grazing in different conditions and conservation *** found that plant and animal diversity and primary production are the most studied ecosystem services,while climate regulation,water supply,nutrient cycling,meat production and erosion control,in that order,are less *** services are *** grazing and glyphosate spraying are the main drivers of grassland *** grazing and conservative stocking rates have been shown to reverse degradation and demonstrate that livestock production is compatible with ecosystem conserva-tion by maintaining regulating and provisioning *** these management strategies are poorly integrated,improving their implementation will require important changes in farmers’decisions and the development of policies that create the economic conditions for this to *** is needed to understand the conditions that prevent the knowledge generated from being transferred to producers and translated into practices that would improve the provision of ecosystem services.

关键词： Salado basin sustainability biodiversity rangelands meat production adaptative multi paddock grazing process technologies agroecology

Understanding pediatric surgical needs in North Korea: a modeling analysis

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World journal of Pediatric Surgery 2024年第1期7卷 47-53页

作者： Phillip j Hsu Sangchul Yoon Kee B Park University of Michigan Ann ArborMichiganUSA Department of Global Health and Social Medicine Harvard Medical SchoolBostonMassachusettsUSA Department of Medical Humanitiesand Social Sciences Yonsei University SeoulSouth Korea

Background Sixty-five percent of children worldwide lack access to surgical care,the majority of whom live in low-income and middle-income countries(LMiCs).Developing surgical infrastructure requires information on surgical need;however,this information is often limited in *** Korea(Democratic People's Republic of Korea,DPRK)has a low amount of publicly available ***,we analyzed available modeled data to understand the causes of pediatric deaths due to conditions treatable with surgery in *** We used World Bank data and models from the Institute for Health Metrics and Evaluation to identify causes of pediatric deaths affecting pediatric patients(agejuries(53.9%),congenital conditions(34.2%),tumors(8.8%),and abdominal conditions(3.2%).DPRK has a lower relative rate of pediatric deaths compared with other LMICs with similar gross domestic product per ***,it has a higher relative rate of pediatric deaths due to conditions requiring treatment with *** injuries contribute significantly to the high rate of pediatric deaths in *** Although DPRK may be allocating overall resources toward pediatric healthcare more efficiently than economic peers,DPRK may benefit from improvement in pediatric surgical *** availability of data and close international collaboration could be potential solutions to bridge this gap.

关键词： pediatric surgical injuries

Distributed Secondary Control Based on Dynamic Diffusion Algorithm for Current Sharing and Average Voltage Regulation in DC Microgrids

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journal of Modern Power Systems and Clean Energy 2024年第2期12卷 597-607页

作者： Dawei Liao Fei Gao Daniel j.Rogers Wentao Huang Dong Liu Houjun Tang Department of Electrical Engineering Shanghai Jiao Tong UniversityShanghaiChina Department of Engineering Science University of OxfordOxford OX12JDU.K. IEEE

This paper introduces a distributed secondary control scheme for achieving current sharing and average voltage regulation objectives in a DC *** proposed scheme employs a dynamic diffusion algorithm(DDA)instead of the consensus algorithm to enable distributed communication among *** help understand DDA,the relation of DDA and other diffusion algorithms is discussed in detail and its superiority is shown by comparison with diffusion and consensus ***,considering the discrete nature and different sampling time of the digital controller and communication network,a z-domain model of the entire DC microgrid is *** influence of communication and secondary control parameters on the system stability is *** on the established model,the tolerable communication rates are ***-time simulations conducted on the OPAL-RT platform validate the effectiveness of the proposed scheme,showcasing its advantages in terms of convergence speed and stability.

关键词： Cooperative control DC microgrid diffusion algorithm discrete-time modeling distributed secondary control