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High Voltage 2021年第1期6卷 16-24页

作者： Muhammad Farasat Abbas Xu‐Chu Yuan Han‐Wei Li jian‐yi xue An‐Bang Sun Guan‐Jun Zhang State Key Laboratory of Electrical Insulation and Power Equipment School of Electrical EngineeringXi'an Jiaotong UniversityXi'anShaanxiChina

A 3D particle‐in‐cell/Monte Carlo collision model is used to investigate the streamer discharge inception in CO_(2) at elevated pressures including gaseous, liquid and supercritical phases. Generation of free electrons is a prerequisite for initiation and development of positive streamers. Field ionization from impurity molecules of low density and low ionization energy is assumed as the source of primary ionization in the model. The field dependent generation rate of electrons is calculated by Zener's model. Tree‐like streamer with filamentary shape presents at the needle tip and propagates to-wards the plane electrode in all three phases of CO_(2), with differing in length and propagation speed. Furthermore, the influence of different parameters such as applied voltage, electrode tip size, and ionizable density and ionization potential of impurity molecules on the evolution of streamer discharge in supercritical CO_(2) are investigated. Simulation results obtained from the 3D model agree well with experimental observations in the literature, which show that field ionization might be one of possible ionization sources in pressurized CO_(2) in the presence of high electric field.

关键词： field. ionization gaseous

Optimization of the co-closing law of guide vanes and blades for bulb turbines based on CFD

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Journal of Hydrodynamics 2024年第2期36卷 363-377页

作者： Hui Liu Yun-fa Lin Yong-guang Cheng Song xue Mao-jia Tang jian Zhang Jia-yi Fan State Key Laboratory of Water Resources Engineering and Management Wuhan UniversityWuhan430072China Dongfang Electric Machinery Co. Ltd.Deyang618000China

The load rejection transient process of bulb turbine units is critical to safety of hydropower stations,and determining appropriate closing laws of guide vanes(GVs)and runner blades(RBs)for this process is of significance.In this study,we proposed a procedure to optimize the co-closing law of GVs and RBs by using computational fluid dynamics(CFD),combined with the design of experiment(DOE)method,approximation model,and genetic optimization algorithm.The sensitivity of closing law parameters on the histories of head,speed,and thrust was analyzed,and a two-stage GVs’closing law associating with a linear RBs’closing law was proposed.The results show that GVs dominate the transient characteristics by controlling the change of discharge.Speeding GVs’first-stage closing speed while shortening first-stage closing time can not only significantly reduce the maximum rotational speed but also suppress the water hammer pressure;slowing GVs’second-stage closing speed is conducive to controlling the maximum reverse axial force.RBs directly affect the runner force.Slowing RBs’closing speed can further reduce the rotational speed and the maximum reverse axial force.The safety margin of each control parameter,flow patterns,and pressure pulsations of a practical hydropower station were all improved after optimization,demonstrating the effectiveness of this method.

关键词： Bulb turbine load rejection transient process double regulation closing law optimization computational fluid dynamics(CFD)

Persymmetric adaptive polarimetric detection of subspace range-spread targets in compound Gaussian sea clutter

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Journal of Systems Engineering and Electronics 2024年第1期35卷 31-42页

作者： XU Shuwen HAO yifan WANG Zhuo xue jian National Key Laboratory of Radar Signal Processing Xidian UniversityXi’an 710071China Xi’an Electronic Engineering Research Institute Xi’an 710100China Beijing Institute of Radio Measurement Beijing 100039China School of Communications and Information Engineering Xi’an University of Posts and TelecommunicationsXi’an 710121China

This paper focuses on the adaptive detection of range and Doppler dual-spread targets in non-homogeneous and nonGaussian sea clutter.The sea clutter from two polarimetric channels is modeled as a compound-Gaussian model with different parameters,and the target is modeled as a subspace rangespread target model.The persymmetric structure is used to model the clutter covariance matrix,in order to reduce the reliance on secondary data of the designed detectors.Three adaptive polarimetric persymmetric detectors are designed based on the generalized likelihood ratio test(GLRT),Rao test,and Wald test.All the proposed detectors have constant falsealarm rate property with respect to the clutter texture,the speckle covariance matrix.Experimental results on simulated and measured data show that three adaptive detectors outperform the competitors in different clutter environments,and the proposed GLRT detector has the best detection performance under different parameters.

关键词： sea clutter adaptive polarimetric detection compound Gaussian model subspace range-spread target persymmetric structure

Differences and Correlations of Morphological and Hemodynamic Parameters between Anterior Circulation Bifurcation and Side-wall Aneurysms

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Current Medical Science 2024年第2期44卷 391-398页

作者： Kai-kai GUO Chang-ya LIU Gao-hui LI jian-ping XIANG Xiao-chang LENG yi-ke CAI xue-bin HU Department of Neurosurgery Union HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430022China Department of Emergency Longhua HospitalShanghai University of Traditional Chinese MedicineShanghai 200032China Artery Flow Technology Co. Ltd.Hangzhou 310051China

Objective:The objective of this research was to explore the difference and correlation of the morphological and hemodynamic features between sidewall and bifurcation aneurysms in anterior circulation arteries,utilizing computational fluid dynamics as a tool for analysis.Methods:In line with the designated inclusion criteria,this study covered 160 aneurysms identified in 131 patients who received treatment at Union Hospital of Tongji Medical College,Huazhong University of Science and Technology,China,from January 2021 to September 2022.Utilizing follow-up digital subtraction angiography(DSA)data,these cases were classified into two distinct groups:the sidewall aneurysm group and the bifurcation aneurysm group.Morphological and hemodynamic parameters in the immediate preoperative period were meticulously calculated and examined in both groups using a three-dimensional DSA reconstruction model.Results:No significant differences were found in the morphological or hemodynamic parameters of bifurcation aneurysms at varied locations within the anterior circulation.However,pronounced differences were identified between sidewall and bifurcation aneurysms in terms of morphological parameters such as the diameter of the parent vessel(Dvessel),inflow angle(θF),and size ratio(SR),as well as the hemodynamic parameter of inflow concentration index(ICI)(P0.5,P<0.001).Conclusions:The significant differences in certain morphological and hemodynamic parameters between sidewall and bifurcation aneurysms emphasize the importance to contemplate variances in threshold values for these parameters when evaluating the risk of rupture in anterior circulation aneurysms.Whether it is a bifurcation or sidewall aneurysm,these disparities should be considered.The morphological parameter SR has the potential to be a valuable clinical tool for promptly distinguishing

关键词： sidewall bifurcation unruptured aneurysms computational fluid dynamics

Synaptotagmins family affect glucose transport in retinal pigment epithelial cells through their ubiquitination-mediated degradation and glucose transporter-1 regulation

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World Journal of Diabetes 2024年第5期15卷 958-976页

作者： Hong Xu Li-Bo Zhang yi-yi Luo Ling Wang Ye-Pin Zhang Pei-Qi Chen xue-ying Ba jian Han Heng Luo Department of Ophthalmology The People’s Hospital of Chuxiong Yi Autonomous Prefecture&The Fourth Affiliated Hospital of Dali UniversityChuxiong Yi Autonomous Prefecture 675000Yunnan ProvinceChina Precision Medicine Center of Chuxiong yi Autonomous Prefecture The People’s Hospital of Chuxiong Yi Autonomous Prefecture&The Fourth Affiliated Hospital of Dali UniversityChuxiong Yi Autonomous Prefecture 675000Yunnan ProvinceChina Department of Endocrinology The People’s Hospital of Chuxiong Yi Autonomous Prefecture&The Fourth Affiliated Hospital of Dali UniversityChuxiong Yi Autonomous Prefecture 675000Yunnan ProvinceChina Department of Pathology The People’s Hospital of Chuxiong Yi Autonomous Prefecture&The Fourth Affiliated Hospital of Dali UniversityChuxiong Yi Autonomous Prefecture 675000Yunnan ProvinceChina

BACKGROUND Synaptotagmins(SYTs)are a family of 17 membrane transporters that function as calcium ion sensors during the release of Ca2+-dependent neurotransmitters and hormones.However,few studies have reported whether members of the SYT family play a role in glucose uptake in diabetic retinopathy(DR)through Ca2+/glucose transporter-1(GLUT1)and the possible regulatory mechanism of SYTs.AIM To elucidate the role of the SYT family in the regulation of glucose transport in retinal pigment epithelial cells and explore its potential as a therapeutic target for the clinical management of DR.METHODS DR was induced by streptozotocin in C57BL/6J mice and by high glucose medium in human retinal pigment epithelial cells(ARPE-19).Bioinformatics analysis,reverse transcriptase-polymerase chain reaction,Western blot,flow cytometry,ELISA,HE staining,and TUNEL staining were used for analysis.RESULTS Six differentially expressed proteins(SYT2,SYT3,SYT4,SYT7,SYT11,and SYT13)were found between the DR and control groups,and SYT4 was highly expressed.Hyperglycemia induces SYT4 overexpression,manipulates Ca2+influx to induce GLUT1 fusion with the plasma membrane,promotes abnormal expression of the glucose transporter GLUT1 and excessive glucose uptake,induces ARPE-19 cell apoptosis,and promotes DR progression.Parkin deficiency inhibits the proteasomal degradation of SYT4 in DR,resulting in SYT4 accumulation and enhanced GLUT1 fusion with the plasma membrane,and these effects were blocked by oe-Parkin treatment.Moreover,dysregulation of the myelin transcription factor 1(Myt1)-induced transcription of SYT4 in DR further activated the SYT4-mediated stimulus-secretion coupling process,and this process was inhibited in the oe-MYT1-treated group.CONCLUSION Our study reveals the key role of SYT4 in regulating glucose transport in retinal pigment epithelial cells during the pathogenesis of DR and the underlying mechanism and suggests potential therapeutic targets for clinical DR.

关键词： Diabetic retinopathy Glucose transporter-1 Synaptotagmin 4 Parkin Myelin transcription factor 1

Research on ozone formation sensitivity based on observational methods:Development history,methodology,and application and prospects in China

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Journal of Environmental Sciences 2024年第4期138卷 543-560页

作者： Wanghui Chu Hong Li Yuanyuan Ji Xin Zhang Likun xue jian Gao Cong An State Key Laboratory of Environmental Criteria and Risk Assessment Chinese Research Academy of Environmental SciencesBeijing 100012China Environment Research Institute Shandong UniversityQingdao 266237China

Observation-based method for O_(3)formation sensitivity research is an important tool to analyze the causes of ground-level O_(3)pollution,which has broad application potentials in determining the O_(3)pollution formation mechanism and developing prevention and control strategies.This paper outlined the development history of research on O_(3)formation sensitivity based on observational methods,described the principle and applicability of the methodology,summarized the relative application results in China and provided recommendations on the prevention and control of O_(3)pollution in China based on relevant study results,and finally pointed out the shortcomings and future development prospects in this field in China.The overview study showed that the O_(3)formation sensitivity in some urban areas in China in recent years presented a gradual shifting tendency from the VOC-limited regime to the transition regime or the NO_(x)-limited regime due to the implementation of the O_(3)precursors emission reduction policies;O_(3)pollution control strategies and precursor control countermeasures should be formulated based on local conditions and the dynamic control capability of O_(3)pollution control measures should be improved.There are still some current deficiencies in the study field in China.Therefore,it is recommended that a stereoscopic monitoring network for atmospheric photochemical components should be further constructed and improved;the atmospheric chemical mechanisms should be vigorously developed,and standardized methods for determining the O_(3)formation sensitivity should be established in China in the near future.

关键词： Observation-based method Ozone formation sensitivity Ozone pollution prevention and control VOCs NO_(x) OBM

Simotang enhances gastrointestinal motility,motilin and cholecystokinin expression in chronically stressed mice

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World Journal of Gastroenterology 2011年第12期17卷 1594-1599页

作者： Guang-Xian Cai Bai-Yan Liu jian yi xue-Mei Chen Fu-Ling Liu Key Laboratory of Internal Medicine Hunan University of Traditional Chinese Medicine Changsha 410007 Hunan Province China

AIM:To investigate the effect of Simotang(Decoction of Four Powered Drugs) on gastrointestinal motility,motilin and cholecystokinin expression in chronically stressed mice.METHODS:Forty mice were randomly divided into control group,stress group(model group),mosapride group and Simotang group,10 in each group.A variety of unpredictable stimulations were used to induce chronic stress in mice.Then,the mice were treated with distilled water,mosapride or Simotang for 7 d.Gastric emptying and intestinal propulsion function were detected.Serum level of motilin was measured by enzyme-linked immunosorbent assay.Expression of cholecystokinin(CCK) in intestine,spinal cord and brain of mice was detected by immunohistochemistry and semi-quantitative reverse transcription polymerase chain reaction,respectively.RESULTS:Simotang improved the gastric emptying and intestinal propulsion in chronically stressed mice.Furthermore,the serum motilin level was significantly higher and the expression levels of CCK-positive cells and genes were significantly lower in intestine,spinal cord and brain of Simotang group than in those of model group(P<0.05).No significant difference was found in serum motilin level and expression levels of CCK-positive cells and genes between the mosapride and Simotang groups.CONCLUSION:Simotang enhances the gastrointestinal motility in chronically stressed mice by regulating the serum motilin level and the expression of cholecystokinin.

关键词： Simotang 长期的应力 Motilin Cholecystokinin 胃肠的活动性

Photocatalytic dicarboxylation of strained C-C bonds with CO_(2) via consecutive visible-light-induced electron transfer

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Chinese Chemical Letters 2024年第6期35卷 268-273页

作者： yi Liu Zhe-Hao Wang Guan-Hua xue Lin Chen Li-Hua Yuan yi-Wen Li Da-Gang Yu jian-Heng Ye Key Laboratory of Green Chemistry&Technology of Ministry of Education College of ChemistrySichuan UniversityChengdu 610064China College of Polymer Science and Engineering State Key Laboratory of Polymer Materials EngineeringSichuan UniversityChengdu 610065China State Key Laboratory of Elemento-Organic Chemistry Nankai UniversityTianjin 300071China

Dicarboxylic acids have a wide range of applications in the polymer industry to construct valuable materials.Photocatalysis has recently emerged as an efficient and sustainable strategy to generate dicarboxylic acids.However,photocatalytic dicarboxylation with CO_(2) is mainly limited to unsaturated bonds,and the dicarboxylation of C-C single bonds still remains a challenge.Herein,we report a photocatalytic dicarboxylation of C-C single bonds in strained rings with CO_(2) units via consecutive photo-induced electron transfer(ConPET).It is also the first photocatalytic reductive ring-opening reaction of cyclobutanes.Notably,this transition-metal-free protocol exhibits good functional group tolerance,broad substrate scope,facile scalability,and easy product derivatizations.Moreover,diacids can easily be derivatized to mainchain liquid crystalline polyesters.

关键词： Consecutive photo-induced electron transfer Visible-light catalysis Dicarboxylation Carbon dioxide Cyclopropanes

Uridine diphosphate glucuronosyltransferase 1A1 prevents the progression of liver injury

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World Journal of Gastroenterology 2024年第9期30卷 1189-1212页

作者： Jin-Lian jiang yi-Yang Zhou Wei-Wei Zhong Lin-Yan Luo Si-ying Liu Xiao-Yu Xie Mao-Yuan Mu Zhi-Gang jiang Yuan xue jian Zhang yi-Huai He Department of Infectious Diseases Affiliated Hospital of Zunyi Medical UniversityZunyi 563000Guizhou ProvinceChina Department of Infectious Diseases Jingmen Central HospitalJingmen 448000Hubei ProvinceChina Department of Respiratory Medicine Anshun People’s HospitalAnshun 561099Guizhou ProvinceChina Department of General Practice Affiliated Hospital of Zunyi Medical UniversityZunyi 563000Guizhou ProvinceChina Department of Intervention Radiology Affiliated Hospital of Zunyi Medical UniversityZunyi 563000Guizhou ProvinceChina School of Public Health Zunyi Medical UniversityZunyi 563099Guizhou ProvinceChina Department of Liver Diseases Third People’s Hospital of ChangzhouChangzhou 213000Jiangsu ProvinceChina Department of Digestion Dafang County People’s HospitalBijie 551600Guizhou ProvinceChina

BACKGROUND Uridine diphosphate glucuronosyltransferase 1A1(UGT1A1)plays a crucial role in metabolizing and detoxifying endogenous and exogenous substances.However,its contribution to the progression of liver damage remains unclear.AIM To determine the role and mechanism of UGT1A1 in liver damage progression.METHODS We investigated the relationship between UGT1A1 expression and liver injury through clinical research.Additionally,the impact and mechanism of UGT1A1 on the progression of liver injury was analyzed through a mouse model study.RESULTS Patients with UGT1A1 gene mutations showed varying degrees of liver damage,while patients with acute-onchronic liver failure(ACLF)exhibited relatively reduced levels of UGT1A1 protein in the liver as compared to patients with chronic hepatitis.This suggests that low UGT1A1 levels may be associated with the progression of liver damage.In mouse models of liver injury induced by carbon tetrachloride(CCl_(4))and concanavalin A(ConA),the hepatic levels of UGT1A1 protein were found to be increased.In mice with lipopolysaccharide or liver steatosis-mediated liver-injury progression,the hepatic protein levels of UGT1A1 were decreased,which is consistent with the observations in patients with ACLF.UGT1A1 knockout exacerbated CCl_(4)-and ConA-induced liver injury,hepatocyte apoptosis and necroptosis in mice,intensified hepatocyte endoplasmic reticulum(ER)stress and oxidative stress,and disrupted lipid metabolism.CONCLUSION UGT1A1 is upregulated as a compensatory response during liver injury,and interference with this upregulation process may worsen liver injury.UGT1A1 reduces ER stress,oxidative stress,and lipid metabolism disorder,thereby mitigating hepatocyte apoptosis and necroptosis.

关键词： Uridine diphosphate glucuronosyltransferase 1A1 Liver injury progression Endoplasmic reticulum stress Oxidative stress Lipid metabolism disorders

Successful treatment of Purpureocillium lilacinum pulmonary infection with isavuconazole: A case report

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World Journal of Clinical Cases 2024年第10期12卷 1772-1777页

作者： xue-Lin Yang Jun-Yu Zhang jian-Min Ren Department of Emergency Medicine Lishui Central HospitalLishui 323000Zhejiang ProvinceChina Department of Hematology Lishui Central HospitalLishui 323000Zhejiang ProvinceChina Department of Clinical Laboratory The Fifth Affiliated Hospital of Wenzhou Medical UniversityLishui 323000Zhejiang ProvinceChina

BACKGROUND Purpureocillium lilacinum(P.lilacinum)is a saprophytic fungus widespread in soil and vegetation.As a causative agent,it is very rarely detected in humans,most commonly in the skin.CASE SUMMARY In this article,we reported the case of a 72-year-old patient with chronic lymphocytic leukemia who was admitted with cough and fever.Computed tomography revealed an infection in the right lower lobe.Bronchoalveolar lavage fluid culture and metagenomic next-generation sequencing were ultimately confirmed to have a pulmonary infection with P.lilacinum.She was eventually discharged with good outcomes after treatment with isavuconazole.CONCLUSION Pulmonary infection with P.lilacinum was exceedingly rare.While currently there are no definitive therapeutic agents,there are reports of high resistance to amphotericin B and fluconazole and good sensitivity to second-generation triazoles.The present report is the first known use of isavuconazole for pulmonary P.lilacinum infection.It provides new evidence for the characterization and treatment of clinical P.lilacinum lung infections.

关键词： Purpureocillium lilacinum Pulmonary infection Isavuconazole Case report