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Journal of Rare Earths 2024年第6期42卷 1182-1186,I0007页

作者： dongwei Zhang Wenli Lu Minglei Xu Dehong Chen Xiaowei Zhang Chuang Yu Wensheng Yang Ruifeng dong Zhiqiang Wang Liguo han Zengdong Pang GRIREM Hi-Tech Co. Ltd.Langfang065201China National Engineering Research Center for Rare Earth China GRINM Group Co.Ltd.Beijing100088China GRIREM Advanced Materials Co. Ltd.Beijing100088China

In light of the difficult removal of harmful impurity tungsten(W)in Ce metal,in this paper a combined vacuum gravity sedimentation-directional solidification method was innovatively designed and the W separation behavior was *** reducing the electron beam power instantly and gradually at reduction rates of 1,3 and 5 kW/min,it is found that W is enriched at the bottom of ingots as the melt *** enrichment effect is much better than that of single purification method and the enrichment degree increases as the beam reduction rate decreases,attributed to the k0(W)>1 andρ(W)>ρ(Ce).Overall,the minimum content of W impurity can decrease from 630 to 0.1 ppm at the top of the ingot,and the purity of Ce increases from 99.932 wt%to 99.995 wt%by this combined ***,this paper provides a new method for the removal of high density and low evaporation coefficient impurities in low vapor pressure rare earth metals.

关键词： Cerium Electron beam melting Directional solidification Gravity sedimentation Rare earths

Machine learning for carbonate formation drilling: Mud loss prediction using seismic attributes and mud loss records

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Petroleum Science 2024年第2期21卷 1241-1256页

作者： Hui-Wen Pang han-Qing Wang Yi-Tian Xiao Yan Jin Yun-Hu Lu Yong-dong Fan Zhen Nie National Key Laboratory of Petroleum Resources and Engineering China University of Petroleum(Beijing)Beijing102249China College of Science China University of Petroleum-BeijingBeijing102249China Petroleum Exploration and Production Research Institute SINOPECBeijing102206China College of Petroleum Engineering China University of Petroleum-BeijingBeijing102249China Research Institute of Petroleum Exploration and Development CNPCBeijing100083China

Due to the complexity and variability of carbonate formation leakage zones, lost circulation prediction and control is one of the major challenges of carbonate drilling. It raises well-control risks and production expenses. This research utilizes the H oilfield as an example, employs seismic features to analyze mud loss prediction, and produces a complete set of pre-drilling mud loss prediction solutions. Firstly, 16seismic attributes are calculated based on the post-stack seismic data, and the mud loss rate per unit footage is specified. The sample set is constructed by extracting each attribute from the seismic trace surrounding 15 typical wells, with a ratio of 8:2 between the training set and the test set. With the calibration results for mud loss rate per unit footage, the nonlinear mapping relationship between seismic attributes and mud loss rate per unit size is established using the mixed density network ***, the influence of the number of sub-Gausses and the uncertainty coefficient on the model's prediction is evaluated. Finally, the model is used in conjunction with downhole drilling conditions to assess the risk of mud loss in various layers and along the wellbore trajectory. The study demonstrates that the mean relative errors of the model for training data and test data are 6.9% and 7.5%, respectively, and that R2is 90% and 88%, respectively, for training data and test data. The accuracy and efficacy of mud loss prediction may be greatly enhanced by combining 16 seismic attributes with the mud loss rate per unit footage and applying machine learning methods. The mud loss prediction model based on the MDN model can not only predict the mud loss rate but also objectively evaluate the prediction based on the quality of the data and the model.

关键词： Lost circulation Risk prediction Machine learning Seismic attributes Mud loss records

The cytosolic isoform of triosephosphate isomerase,ZmTPI4,is required for kernel development and starch synthesis in maize(Zea mays L.)

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The Crop Journal 2024年第2期12卷 401-410页

作者： Wenyu Li han Wang Qiuyue Xu Long Zhang Yan Wang Yongbiao Yu Xiangkun Guo Zhiwei Zhang Yongbin dong Yuling Li State Key Laboratory of Wheat and Maize Crop Science Collaborative Innovation Center of Henan Grain CropsCollege of AgronomyHenan Agricultural UniversityLongzi Lake CampusZhengzhou 450046HenanChina

Triosephosphate isomerase(TPI)is an enzyme that functions in plant energy production,accumulation,and *** understand its function in maize,we characterized a maize TPI mutant,*** comparison to the wild type,zmtpi4 mutants showed altered ear development,reduced kernel weight and starch content,modified starch granule morphology,and altered amylose and amylopectin ***,ATP,and pyruvate contents were reduced,indicating ZmTPI4 was involved in *** subcellular localization confirmed ZmTPI4 as a cytosolic rather than a plastid isoform of TPI,the zmtpi4 mutant showed reduced leaf size and chlorophyll *** of ZmTPI4 in Arabidopsis led to enlarged leaves and increased seed weight,suggesting a positive regulatory role of ZmTPI4 in kernel weight and starch *** conclude that ZmTPI4 functions in maize kernel development,starch synthesis,glycolysis,and photosynthesis.

关键词： Maize Kernel Starch Weight Photosynthesis

Mechanical behaviours of bedded sandstone under hydromechanical coupling

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第4期16卷 1245-1261页

作者： Junwen Zhang Zhixiang Song Lichao Zhang Shaokang Wu Shanyong Wang Yang Zhang Xukai dong Jinxin Wang Yanbo han Baohua Kan School of Energy and Mining Engineering China University of Mining and Technology (Beijing)Beijing100083China Jarud Banner Zhahanao'er Coal Industry Co. Ltd.ZhaluteqiInner Mongolia029200China Priority Research Centre for Geotechnical Science & Engineering The University of NewcastleCallaghanNSW 2308Australia

The combination of the dipping effect and hydromechanical(H-M)coupling effect can easily lead to water inrush disasters in water-rich roadways with different dip angles in coal ***,H-M coupling tests of bedded sandstones under identical osmotic pressure and various confining pressures were ***,the evolution curves of stress-strain,permeability and damage,macro-and mesoscopic failure characteristics were ***,the mechanical behaviour was characterized,and finally the failure mechanism was *** results showed that:(1)The failure of the sandstone with the bedding angle of 45°or 60°was the structure-dominant type,while that with the bedding angle of 0°,30°or 90°was the force-dominant type.(2)When the bedding angle was in the range of(0°,30°)or(45°,90°),the confining pressure played a dominant role in influencing the peak ***,withinβ∈(30°,45°),the bedding effect played a dominant role in the peak strength.(3)With the increase in bedding angle,the cohesion increased first,then decreased and finally increased,while the internal friction angle was the opposite.(4)When the bedding angle was 0°or 30°,the“water wedging”effect and the“bedding buckling”effect would lead to the forking or converging shear *** the bedding angle was 45°or 60°,the sliding friction effect would lead to the shear slipping *** the bedding angle was 90°,the combination of the“bedding buckling”effect and shear effect would lead to the mixed tension-shear *** above conclusions obtained are helpful for the prevention of water inrush disasters in water-rich roadways with different dips in coal mines.

关键词： Hydromechanical coupling Bedded sandstones Mechanical behaviour Bedding effect Failure mechanism

A 12-month follow-up study of discharged patients with acute pancreatitis:An acute condition with prolonged sequela

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Chinese Medical Journal 2024年第2期137卷 250-252页

作者： hanyue Ding Jiayuan Dai Jiaye Lin Liang Gong han Sun Kai Song Feng Xie dong Wu Department of Gastroenterology Peking Union Medical College HospitalPeking Union Medical College and Chinese Academy of Medical ScienceBeijing 100730China School of Population Medicine and Public Health Peking Union Medical College and Chinese Academy of Medical ScienceBeijing 100730China JC School of Public Health and Primary Care Faculty of MedicineThe Chinese University of Hong KongHong Kong Special Administrative RegionChina Emergency Department Peking Union Medical College HospitalPeking Union Medical College and Chinese Academy of Medical ScienceBeijing 100730China Department of Health Research Methods Evidence and ImpactMcMaster UniversityHamiltonCanada Centre for Health Economics and Policy Analysis McMaster UniversityHamiltonCanada State Key Laboratory of Complex Severe and Rare Diseases Peking Union Medical College HospitalPeking Union Medical College and Chinese Academy of Medical ScienceBeijing 100730China Clinical Epidemiology Unit International Clinical Epidemiology NetworkBeijing 100730China

To the Editor:Acute pancreatitis(AP)is the most common gastrointestinal condition that leads to acute hospitalization.[1]The incidence of AP has increased in recent decades,with a current global incidence of 34/100,000,probably due to a rising trend of obesity and gallstone *** is associated with remarkable pain,reduced quality of life(QoL),and even death,thus posing a heavy socioeconomic *** addition,approximately 22%of AP patients experience recurrent AP(RAP)and 10%of AP patients progress to chronic pancreatitis.[2]Petrov and Yadav[3]have,therefore,argued that AP should not be considered as an acute and self-limiting *** and long-term care after AP have drawn widespread attention,which has improved patients’physical and mental health.

关键词： patients pancreatitis acute

Recent progress in the deactivation mechanism of zeolite catalysts in methanol to olefins

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Science China Chemistry 2024年

作者： Sheng Fan han Wang Sen Wang Mei dong Weibin Fan State Key Laboratory of Coal Conversion Institute of Coal Chemistry Chinese Academy of Sciences University of Chinese Academy of Sciences

Methanol to olefins(MTO) as an important reaction in C1 chemistry can effectively transform non-petroleum carbon resources into value-added chemicals. Zeolites have been widely used as MTO catalysts. However, they usually suffer from a rapid deactivation due to bulky coke species production, and thus require continuous regenerations in industrial application. The key to design and develop highly stable zeolite catalysts for MTO process is to unravel the deactivation mechanism and clarify the structure–performance relationship of catalysts. Here, in this mini-review, we investigate the critical intermediate species inducing zeolite deactivation and analyze the formation and evolution pathways of polycyclic aromatic hydrocarbons(PAHs)that are the precursors of carbonaceous deposits. In addition, some methods to alleviate the coking mainly including acid regulation, morphology modification and process optimization, are also summarized.

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Comparative transcriptomic evidence of physiological changes and potential relationships in vertebrates under different dormancy states

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Zoological Research 2024年第2期45卷 341-354页

作者： Yu-han Niu Li-Hong Guan Cheng Wang Hai-Feng Jiang Guo-Gang Li Lian-dong Yang Shun-Ping He State Key Laboratory of Freshwater Ecology and Biotechnology Institute of HydrobiologyChinese Academy of SciencesWuhanHubei 430072China College of Life Sciences Qinghai Normal UniversityXiningQinghai 810008China Academy of Plateau Science and Sustainability Qinghai Normal UniversityXiningQinghai 810016China Key Laboratory of Biodiversity Formation Mechanism and Comprehensive Utilization of the Qinghai-Tibet Plateau in Qinghai Province Qinghai Normal UniversityXiningQinghai 810008China College of Life Sciences and Technology Xinxiang Medical UniversityXinxiangHenan 453003China College of Animal Science and Technology Northwest A&F UniversityYanglingShaanxi 712100China

Dormancy represents a fascinating adaptive strategy for organisms to survive in unforgiving *** a period of dormancy,organisms often exhibit exceptional *** period is typically divided into hibernation and aestivation based on seasonal ***,the mechanisms by which organisms adapt to their environments during dormancy,as well as the potential relationships between different states of dormancy,deserve further ***,we selected Perccottus glenii and Protopterus annectens as the primary subjects to study hibernation and aestivation,*** on histological and transcriptomic analysis of multiple organs,we discovered that dormancy involved a coordinated functional response across *** analyses revealed noteworthy disparities between the two dormant species in their responses to extreme ***,similarities in gene expression patterns pertaining to energy metabolism,neural activity,and biosynthesis were noted during hibernation,suggesting a potential correlation between hibernation and *** further explore the relationship between these two phenomena,we analyzed other dormancy-capable species using data from publicly available *** comparative analysis revealed that most orthologous genes involved in metabolism,cell proliferation,and neural function exhibited consistent expression patterns during dormancy,indicating that the observed similarity between hibernation and aestivation may be attributable to convergent *** conclusion,this study enhances our comprehension of the dormancy phenomenon and offers new insights into the molecular mechanisms underpinning vertebrate dormancy.

关键词： Hibernation Aestivation Multi-organs Convergent evolution

Inferring the Effects of Protein Variants on Protein-Protein Interactions with Interpretable Transformer Representations

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Research 2024年第2期2023卷 473-489页

作者： Zhe Liu Wei Qian Wenxiang Cai Weichen Song Weidi Wang Dhruba Tara Maharjan Wenhong Cheng Jue Chen han Wang dong Xu Guan Ning Lin Shanghai Mental Health Center Shanghai Jiao Tong University School of MedicineSchool of Biomedical EngineeringShanghai Jiao Tong UniversityShanghaiChina Shanghai Key Laboratory of Psychotic Disorders ShanghaiChina School of Information Science and Technology Institute of Computational BiologyNortheast Normal UniversityChangchunChina Department of Electrical Engineering and Computer Science University of MissouriColumbiaMO 65211USA Christopher S.Bond Life Sciences Center University of MissouriColumbiaMO 65211USA

Identifying pathogenetic variants and inferring their impact on protein-protein interactions sheds light on their functional consequences on *** by the availability of experimental data on the consequences of protein interaction,most existing methods focus on building models to predict changes in protein binding ***,we introduced MIPPI,an end-to-end,interpretable transformer-based deep learning model that learns features directly from sequences by leveraging the interaction data from *** was specifically trained to determine the types of variant impact(increasing,decreasing,disrupting,and no effect)on protein-protein *** demonstrate the accuracy of MIPPI and provide interpretation through the analysis of learned attention weights,which exhibit correlations with the amino acids interacting with the ***,we showed the practicality of MIPPI in prioritizing de novo mutations associated with complex neurodevelopmental disorders and the potential to determine the pathogenic and driving ***,we experimentally validated the functional impact of several variants identified in patients with such ***,MIPPI emerges as a versatile,robust,and interpretable model,capable of effectively predicting mutation impacts on protein-protein interactions and facilitating the discovery of clinically actionable variants.

关键词： consequences weights versatile

Solid-state non-volatile memories based on vdW heterostructure-based vertical-transport ferroelectric field-effect transistors

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Science China(Information Sciences) 2024年第6期67卷 198-206页

作者： Qiyu YANG Zheng-dong LUO Fei XIAO Junpeng ZhanG Dawei ZhanG dongxin TAN Xuetao GAN Yan LIU Zhufei CHU Yinshui XIA Genquan han hangzhou Institute of Technology Xidian University State Key Discipline Laboratory of Wide Band Gap Semiconductor Technology School of MicroelectronicsXidian University School of Artificial Intelligence Xidian University School of Materials Science and Engineering University of New South Wales (UNSW) Sydney ARC Centre of Excellence in Future Low-Energy Electronics Technologies (FLEET) University of New South Wales (UNSW) Sydney Key Laboratory of Light Field Manipulation and Information Acquisition Ministry of Industry and Information Technologyand Shaanxi Key Laboratory of Optical Information TechnologySchool of Physical Science and TechnologyNorthwestern Polytechnical University Faculty of Electrical Engineering and Computer Science Ningbo University

Driven by the explosive development of data-centric computation applications, it is becoming urgent to develop in-memory computing devices that are beyond the von Neumann architecture with an arrangement of separated logic and memory components. The transistor-type solid-state non-volatile memories,such as ferroelectric field-effect transistors(Fe FETs), have long been regarded as a competitive candidate for future in-memory computing architectures. However, the density scaling towards high-density arrays would require advanced Fe FETs with reduced footprints, which remains a great challenge so far. Here, a vertical-transport(VT) Fe FET that flips the charge transport channel perpendicular to the substrate plane is proposed, in which a ferroelectric gate and a van der Waals(vd W) heterojunction channel are vertically integrated, effectively reducing the device footprints. The proposed VT-Fe FET shows not only the robust binary non-volatile memory states but also several key synaptic functionalities at the device level. An artificial neural network with supervised learning was simulated based on the device conductance switching properties,showing excellent classification accuracy for the MNIST handwritten digits. These findings suggest that the proposed VT-Fe FET could offer a new solution for future non-volatile memories as well as more advanced neuromorphic systems.

关键词： vdW heterostructure non-volatile memory vertical-transport transistor ferroelectric field-effect transistor memristive devices

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Elucidating the cardioprotective mechanisms of sodium-glucose cotransporter-2 inhibitors beyond glycemic control

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World Journal of Diabetes 2024年第2期15卷 137-141页

作者： Ke-Xin Zhang Cheng-Xia Kan Fang han Jing-Wen Zhang Xiao-dong Sun Department of Endocrinology and Metabolism Affiliated Hospital of Weifang Medical UniversityWeifang 261031Shandong ProvinceChina

Sodium-glucose cotransporter-2(SGLT2)inhibitors have emerged as a pivotal intervention in diabetes management,offering significant cardiovascular ***,in particular,has demonstrated cardioprotective effects beyond its glucose-lowering action,reducing heart failure hospitalizations and improving cardiac *** note,the cardioprotective mechanisms appear to be independent of glucose lowering,possibly mediated through several mechanisms involving shifts in cardiac metabolism and anti-fibrotic,anti-inflammatory,and anti-oxidative *** editorial summarizes the multifaceted cardiovascular advantages of SGLT2 inhibitors,highlighting the need for further research to elucidate their full therapeutic potential in cardiac care.

关键词： Diabetes Sodium-glucose cotransporter-2 Cardiovascular diseases Empagliflozin