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Acute upper gastrointestinal bleeding due to portal hypertension in a patient with primary myelofibrosis:A case report

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World Journal of Clinical Cases 2024年第15期12卷 2621-2626页

作者： Yu chen bing-bing Kong He Yin Hao Liu Sheng Wu Ting Xu Department of Emergency Beijing Tsinghua Changgung HospitalSchool of Clinical MedicineTsinghua UniversityBeijing 102218China Department of Pathology Beijing Tsinghua Changgung HospitalSchool of Clinical MedicineTsinghua UniversityBeijing 102218China

BACKGROUND Acute upper gastrointestinal bleeding is a common medical emergency that has a 10%hospital mortality rate.According to the etiology,this disease can be divided into acute varicose veins and nonvaricose veins.Bleeding from esophageal varices is a life-threatening complication of portal hypertension.Portal hypertension is a clinical syndrome defined as a portal venous pressure that exceeds 10 mmHg.Cirrhosis is the most common cause of portal hypertension,and thrombosis of the portal system not associated with liver cirrhosis is the second most common cause of portal hypertension in the Western world.Primary myeloproliferative disorders are the main cause of portal venous thrombosis,and somatic mutations in the Janus kinase 2 gene(JAK2 V617F)can be found in approximately 90% of polycythemia vera,50% of essential thrombocyrosis and 50% of primary myelofibrosis.CASE SUMMARY We present a rare case of primary myelofibrosis with gastrointestinal bleeding as the primary manifestation that presented as portal-superior-splenic mesenteric vein thrombosis.Peripheral blood tests revealed the presence of the JAK2 V617F mutation.Bone marrow biopsy ultimately confirmed the diagnosis of myelofibrosis(MF-2 grade).CONCLUSION In patients with acute esophageal variceal bleeding due to portal hypertension and vein thrombosis without cirrhosis,the possibility of myeloproliferative neoplasms should be considered,and the JAK2 mutation test should be performed.

关键词： Acute esophageal variceal bleeding Portal hypertension Myelofibrosis JAK2 V617F mutation Case report

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Effects of physical crust on soil detachment by overland flow in the Loess Plateau region of China

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International Soil and Water Conservation Research 2024年第1期12卷 107-120页

作者： Jiaxin Liu Liding chen bing Wang Xiaoyu Peng School of Ecology and Environmental Science Yunnan UniversityKunming650091China State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau Institute of Soil and Water ConservationNorthwest A&F UniversityYanglingShaanxi712100China University of Chinese Academy of Sciences Beijing100049China

Physical soil crust(PSC),a key component of surface soil structure,exists extensively in loess areas.PSC is considered to have a significant effect on soil detachment processes.However,the long-term effects and the corresponding mechanisms of PSC on soil detachment by overland flow are still not well understood,especially in natural environments.To investigate temporal variation in soil erosion resistance and the underlying factors during PSC formation,an 8×8-m soil plot was exposed to natural conditions in the Loess Plateau over a 524-day period spanning two rainy seasons and a winter between them.A flume test was conducted to determine soil detachment capacity(Dc)under six designed flow shear stress levels(5.66-22.11 Pa)using crusted(SC)and non-crusted(NSC)soil samples at different PSC development stages.Subsequently,two soil erosion resistance parameters,rill erodibility(K_(r))and critical shear stress(τ_(c)),were calculated.Over time,in the SC and NSC treatments,K_(r)decreased from 0.516 to 0.120 s m^(-1)and 0.521 to 0.223 s m^(-1),respectively,whileτ_(c)increased from 0.49 to 4.42 Pa and 0.26-2.46 Pa,respectively.Variation in soil erosion resistance was rapid in the first one to two months,and then slowed down,with slight fluctuations afterwards.In the SC treatment,K_(r)was 42%lower andτ_(c)was 67%greater than those in the NSC treatment.Soil properties changed greatly for both treatments.SCT increased from 0 to 7.09 mm in the SC treatment.Coh increased from 2.91 to 9.04 kPa and 3.01-4.78 kPa in SC and NSC treatments,respectively.Both soil erosion resistance parameters could be well predicted by SCT and Coh in the SC treatment(R^(2)≥0.82),while their best predictor was Coh in the NSC treatment(R^(2)≥0.90).The results demonstrate that PSC formation enhances soil erosion resistance in the soil detachment process in the loess region under natural conditions.Our study revealed the important role and complexity of PSC in the process of soil erosion,and provided theoretical and data support for accurate understandi

关键词： Physical soil crust formation Soil heterogeneity Rill erodibility Critical shear stress

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Optimal SOC Headroom of Pump Storage Hydropower for Maximizing Joint Revenue from Day-ahead and Real-time Markets Under Regional Transmission Organization Dispatch

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Journal of Modern Power Systems and Clean Energy 2024年第1期12卷 238-250页

作者： Yikui Liu bing Huang Yang Lin Yonghong chen Lei Wu Electrical and Computer Engineering Department Stevens Institute of TechnologyHobokenNJ 07030USA Midcontinent Independent System Operator Inc.CarmelIN 46032USA

In response to the increasing penetration of volatile and uncertain renewable energy,the regional transmission organizations(RTOs)have been recently focusing on enhancing the models of pump storage hydropower(PSH)plants,which are one of the key flexibility assets in the day-ahead(DA)and real-time(RT)markets,to further boost their flexibility provision potentials.Inspired by the recent research works that explored the potential benefits of excluding PSHs’cost-related terms from the objective functions of the DA market clearing model,this paper completes a rolling RT market scheme that is compatible with the DA market.Then,with the vision that PSHs could be permitted to submit state-of-charge(SOC)headrooms in the DA market and to release them in the RT market,this paper uncovers that PSHs could increase the total revenues from the two markets by optimizing their SOC headrooms,assisted by the proposed tri-level optimal SOC headroom model.Specifically,in the proposed tri-level model,the middle and lower levels respectively mimic the DA and RT scheduling processes of PSHs,and the upper level determines the optimal headrooms to be submitted to the RTO for maximizing the total revenue from the two markets.Numerical case studies quantify the profitability of the optimal SOC headroom submissions as well as the associated financial risks.

关键词： Pump storage hydropower energy market state-of-charge(SOC) headroom market revenue tri-level problem

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A non-probabilistic reliability topology optimization method based on aggregation function and matrix multiplication considering buckling response constraints

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Applied Mathematics and Mechanics(English Edition) 2024年第2期45卷 321-336页

作者： Lei WANG Yingge LIU Juxi HU Weimin chen bing HAN Institute of Solid Mechanics School of Aeronautic Science and EngineeringBeihang UniversityBeijing 100191China Aircraft and Propulsion Laboratory Ningbo Institute of TechnologyBeihang UniversityNingbo 315100Zhejiang ProvinceChina State Key Laboratory of Navigation and Safety Technology Shanghai Ship and Shipping Research InstituteShanghai 200135China National Engineering Research Center of Ship&Shipping Control System Shanghai Ship and Shipping Research InstituteShanghai 200135China

A non-probabilistic reliability topology optimization method is proposed based on the aggregation function and matrix multiplication.The expression of the geometric stiffness matrix is derived,the finite element linear buckling analysis is conducted,and the sensitivity solution of the linear buckling factor is achieved.For a specific problem in linear buckling topology optimization,a Heaviside projection function based on the exponential smooth growth is developed to eliminate the gray cells.The aggregation function method is used to consider the high-order eigenvalues,so as to obtain continuous sensitivity information and refined structural design.With cyclic matrix programming,a fast topology optimization method that can be used to efficiently obtain the unit assembly and sensitivity solution is conducted.To maximize the buckling load,under the constraint of the given buckling load,two types of topological optimization columns are constructed.The variable density method is used to achieve the topology optimization solution along with the moving asymptote optimization algorithm.The vertex method and the matching point method are used to carry out an uncertainty propagation analysis,and the non-probability reliability topology optimization method considering buckling responses is developed based on the transformation of non-probability reliability indices based on the characteristic distance.Finally,the differences in the structural topology optimization under different reliability degrees are illustrated by examples.

关键词： buckling topology optimization aggregation function uncertainty propagation analysis non-probabilistic reliability

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The roles of macrophage migration inhibitory factor in retinal diseases

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Neural Regeneration Research 2024年第2期19卷 309-315页

作者： Hongbing Zhang Xianjiao Zhang Hongsong Li bing Wang Pei chen Jiamin Meng Shaanxi Institute of Ophthalmology Xi’anShaanxi ProvinceChina Department of Ophthalmology First Affiliated Hospital of Northwest UniversityXi’anShaanxi ProvinceChina Department of Pathology First Affiliated Hospital of Northwest UniversityXi’anShaanxi ProvinceChina

Macrophage migration inhibitory factor(MIF),a multifunctional cytokine,is secreted by various cells and participates in inflammatory reactions,including innate and adaptive immunity.There are some evidences that MIF is involved in many vitreoretinal diseases.For example,MIF can exacerbate many types of uveitis;measurements of MIF levels can be used to monitor the effectiveness of uveitis treatment.MIF also alleviates trauma-induced and glaucoma-induced optic nerve damage.Furthermore,MIF is critical for retinal/choroidal neovascularization,especially complex neovascularization.MIF exacerbates retinal degeneration;thus,anti-MIF therapy may help to mitigate retinal degeneration.MIF protects uveal melanoma from attacks by natural killer cells.The mechanism underlying the effects of MIF in these diseases has been demonstrated:it binds to cluster of differentiation 74,inhibits the c-Jun N-terminal kinase pathway,and triggers mitogen-activated protein kinases,extracellular signal-regulated kinase-1/2,and the phosphoinositide-3-kinase/Akt pathway.MIF also upregulates Toll-like receptor 4 and activates the nuclear factor kappa-B signaling pathway.This review focuses on the structure and function of MIF and its receptors,including the effects of MIF on uveal inflammation,retinal degeneration,optic neuropathy,retinal/choroidal neovascularization,and uveal melanoma.

关键词： diabetic retinopathy glaucoma macrophage migration inhibitory factor migration inhibitory factor receptor optic neuropathy retinal degeneration retinal neovascular uveal melanoma uveitis

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Methods,Mechanisms,and Application Prospects for Enhancing Extracellular Vesicle Uptake

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Current Medical Science 2024年第2期44卷 247-260页

作者： Ying-peng XU Tao JIANG Xiao-fan YANG Zhen-bing chen Department of Hand Surgery Union HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan430022China

Extracellular vesicles(EVs)are considered to be a new generation of bioinspired nanoscale drug delivery systems due to their low immunogenicity,natural functionality,and excellent biocompatibility.However,limitations such as low uptake efficiency,insufficient production,and inhomogeneous performance undermine their potential.To address these issues,numerous researchers have put forward various methods and applications for enhancing EV uptake in recent decades.In this review,we introduce various methods for the cellular uptake of EVs and summarize recent advances on the methods and mechanisms for enhancing EV uptake.In addition,we provide further understanding regarding enhancing EV uptake and put forward prospects and challenges for the development of EV-based therapy in the future.

关键词： extracellular vesicles exosomes extracellular vesicle uptake extracellular vesiclebased therapy

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Analysis of metabolic characteristics of metabolic syndrome in elderly patients with gastric cancer by non-targeted metabolomics

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World Journal of Gastrointestinal Oncology 2024年第6期16卷 2419-2428页

作者： Huan Zhang Wen-bing Shen Lin chen Medical School of Chinese PLA Chinese PLA General HospitalBeijing 100853China Department of Gastrointestinal Surgery Shanghai Sixth People’s HospitalShanghai 250063China Department of General Surgery The First Medical Center of Chinese PLA General HospitalBeijing 100853China

BACKGROUND The relationship between metabolic syndrome(MetS)and gastric cancer(GC),which is a common metabolic disease,has attracted much attention.However,the specific metabolic characteristics of MetS in elderly patients with GC remain unclear.AIM To investigate the differentially abundant metabolites and metabolic pathways between preoperative frailty and MetS in elderly patients with GC based on nontargeted metabolomics techniques.METHODS In this study,125 patients with nonfrail nonmeal GC were selected as the control group,and 50 patients with GC in the frail group were selected as the frail group.Sixty-five patients with GC combined with MetS alone were included in the MetS group,and 50 patients with GC combined with MetS were included in the MetS group.Nontargeted metabolomics techniques were used to measure plasma metabolite levels by ultrahigh-performance liquid chromatography-mass spectrometry.Multivariate statistical analysis was performed by principal component analysis,orthogonal partial least squares,pattern recognition analysis,cluster analysis,and metabolic pathway annotation.RESULTS A total of 125 different metabolites,including amino acids,glycerophospholipids,sphingolipids,fatty acids,sugars,nucleosides and nucleotides,and acidic compounds,were identified via nontargeted metabolomics techniques.Compared with those in the control group,there were 41,32,and 52 different metabolites in the MetS group,the debilitated group,and the combined group,respectively.Lipid metabolites were significantly increased in the MetS group.In the weak group,amino acids and most glycerol phospholipid metabolites decreased significantly,and fatty acids and sphingosine increased significantly.The combined group was characterized by significantly increased levels of nucleotide metabolites and acidic compounds.The alanine,aspartic acid,and glutamate metabolic pathways were obviously enriched in the asthenic group,and the glycerol and phospholipid metabolic pathways were obviously enriched in the combined group.CONCLUSION

关键词： Nervous breakdown Metabolic syndrome Elderly individuals Gastric cancer Nontargeted metabolomics

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Inclusions modification by rare earth in steel and the resulting properties: A review

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Journal of Rare Earths 2024年第3期42卷 431-445,I0001页

作者： Xiaoqiang Wang Zhiwei Wu bing Li Wenxiong chen Jun Zhang Jian Mao College of Materials Science and Engineering Sichuan UniversityChengdu610065China chengdu Advanced Metal Materials Industry Technology Research Institute Co. Ltd.Chengdu610303China State Key Laboratory of Metal Material for Marine Equipment and Application Anshan114009China

Rare earth(RE) elements are excellent modifiers for non-metallic inclusions that inevitably appear in steel and affect steel properties. This paper reviews the research status of inclusions modification by RE elements and the changes it cause on steel properties. First, the inclusion changes caused by RE modification are described. Generally, after adding pure RE, the main evolution of inclusions occurs as M →M + RE-Al-O → RE-Al-O + RE_(2)O_(2)S → RE_(2)O_(2)S + RE—S/RE_(2)O_(2)S + RE-O with an increase in the RE content(M represents the inclusions before RE addition). The type of final inclusion obtained after RE modification is related to the relative contents of S and O in the steel. Moreover, fine, regular, and uniformly distributed inclusions can be obtained with appropriate RE addition. However, the effectiveness of inclusions modification by adding both RE and non-RE elements is closely related to the order of their addition. Second, the applications and advantages of thermodynamic calculations in the study of RE-modified inclusions are introduced. Third, the changes in the corrosion resistance, impact properties,and other properties of steel caused by the modification of inclusions by RE are reviewed. Finally, the perspectives and trends of inclusions modified by RE elements in the steel industry are presented.

关键词： Rare earths Inclusions Modification Thermodynamic calculation Properties change

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Spatiotemporal dynamics of the social structure of Indo-Pacific humpback dolphins(Sousa chinensis)in Xiamen waters from 2007 to 2019

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Zoological Research 2024年第2期45卷 439-450页

作者： Yi Lu Xin-Rong Xu bing-Yao chen Thomas A Jefferson Holly Fearnbach Guang Yang Jiangsu Key Laboratory for Biodiversity and Biotechnology College of Life SciencesNanjing Normal UniversityNanjingJiangsu 210023China Clymene Enterprises LakesideCalifornia 92040USA Marine Mammal Research SR3SeaLife ResponseRehabilitation and ResearchWA 98275USA Southern Marine Science and Engineering Guangdong Laboratory(Guangzhou) No.1119Haibin RoadNansha DistrictGuangzhouGuangdong 511458China

As highly social animals,Indo-Pacific humpback dolphins(Sousa chinensis)exhibit community differentiation.Nevertheless,our understanding of the external and internal factors influencing these dynamics,as well as their spatiotemporal variations,is still limited.In the present study,variations in the social structure of an endangered Indo-Pacific humpback dolphin population in Xiamen Bay,China,were monitored over two distinct periods(2007–2010 and 2017–2019)to analyze the effects of habitat utilization and the composition of individuals within the population.In both periods,the population demonstrated a strikingly similar pattern of social differentiation,characterized by the division of individuals into two main clusters and one small cluster.Spatially,the two primary clusters occupied the eastern and western waters,respectively,although the core distribution area of the eastern cluster shifted further eastward between the two periods.Despite this distribution shift,the temporal stability of the social structure and inter-associations within the eastern cluster remained unaffected.A subset of 16individuals observed in both periods,comprising 51.6%and 43.2%of the population in each respective period,emerged as a foundational element of the social structure and may be responsible for sustaining social structure stability,especially during the 2007–2010 period.These observations suggest that the composition of dominant individuals,an internal factor,had a more substantial influence on the formation of the social network than changes in habitat use,an external factor.Consequently,the study proposes distinct conservation measures tailored to each of the two main clusters.

关键词： Social differentiation Social structure Sousa chinensis Dynamics Conservation

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Real-time arrival picking of rock microfracture signals based on convolutional-recurrent neural network and its engineering application

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第3期16卷 761-777页

作者： bing-Rui chen Xu Wang Xinhao Zhu Qing Wang Houlin Xie State Key Laboratory of Geomechanics and Geotechnical Engineering Institute of Rock and Soil MechanicsChinese Academy of SciencesWuhan430071China University of Chinese Academy of Sciences Beijing100049China

Accurately picking P-and S-wave arrivals of microseismic(MS)signals in real-time directly influences the early warning of rock mass failure.A common contradiction between accuracy and computation exists in the current arrival picking methods.Thus,a real-time arrival picking method of MS signals is constructed based on a convolutional-recurrent neural network(CRNN).This method fully utilizes the advantages of convolutional layers and gated recurrent units(GRU)in extracting short-and long-term features,in order to create a precise and lightweight arrival picking structure.Then,the synthetic signals with field noises are used to evaluate the hyperparameters of the CRNN model and obtain an optimal CRNN model.The actual operation on various devices indicates that compared with the U-Net method,the CRNN method achieves faster arrival picking with less performance consumption.An application of large underground caverns in the Yebatan hydropower station(YBT)project shows that compared with the short-term average/long-term average(STA/LTA),Akaike information criterion(AIC)and U-Net methods,the CRNN method has the highest accuracy within four sampling points,which is 87.44%for P-wave and 91.29%for S-wave,respectively.The sum of mean absolute errors(MAESUM)of the CRNN method is 4.22 sampling points,which is lower than that of the other methods.Among the four methods,the MS sources location calculated based on the CRNN method shows the best consistency with the actual failure,which occurs at the junction of the shaft and the second gallery.Thus,the proposed method can pick up P-and S-arrival accurately and rapidly,providing a reference for rock failure analysis and evaluation in engineering applications.

关键词： Rock mass failure Microseismic event P-wave arrival S-wave arrival Deep learning

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