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A compact streamfunction-velocity scheme for the 2-D unsteady incompressible Navier-Stokes equations in arbitrary curvilinear coordinates

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Journal of Hydrodynamics 2019年第4期31卷 827-839页

作者： jian-xin qiu Bo Peng Zhen-fu Tian Department of Mechanics and Engineering Science Fudan University Shanghai 200433 China

A streamfunction-velocity formulation-based compact difference method is suggested for solving the unsteady incompressible Navier-Stokes equations in the arbitrary curvilinear coordinates, in which the stream function and its first derivatives as the unknown variables are utilized. Numerical examples, involving the boundary layer problem, a constricted channel flow, driven polar cavity flow and trapezoidal cavity flow problem, are solved by the present method. Numerical results demonstrate the accuracy of the proposed scheme and exhibit the numerical capability to simulate the flow problems on geometries beyond rectangular. For driven polar cavity flow problem, the results show that the flow for Re = 5 000 is not steady but time-periodic, and the critical Reynold number (Rec) for the occurrence of a Hopf bifurcation is given.

关键词： Streamfunction-velocity formulation arbitrary curvilinear coordinates compact scheme unsteady incompressible flow

Inguinal and subinguinal micro-varicocelectomy, the optimal surgical management of varicocele： a meta-analysis

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Asian Journal of Andrology 2015年第1期17卷 74-80,I0008页

作者： Jun Wang Shu-Jie Xia Zhi-Hong Liu Le Tao Ji-Fu Ge Chen-Min Xu jian-xin qiu Department of Urology Shanghai First People's Hospital Medical College of Shanghai Jiao Tong University Shanghai China.

Conventional meta-analyses have shown inconsistent results for the efficacy of various treatments of varicoceles. Therefore, we performed a multiple-treatment meta-analysis to assess the effectiveness and safety of 10 methods of varicocelectomy and embolization/sclerotherapy. We systematically reviewed 35 randomized controlled trials and observational studies, from 1966 to August 5, 2013, which compared any of the following treatments for varococeles： laparoscopic, retroperitoneal, open inguinal and subinguinal varicocelectomy, microsurgical subinguinal and inguinal varicocelectomy, percutaneous venous embolization, Tauber antegrade sclerotherapy, retrograde sclerotherapy and expectant therapy （no treatment）. Inguinal and subinguinal microsurgery, open inguinal, laparoscopic varicocelectomy showed a significant advantage over expectant therapy in terms of pregnancy rates （odds ratio （OR）： 3.48, 2.68, 2.92 and 2.90, respectively）. Compared with retroperitoneal open surgery, inguinal microsurgery showed an improvement of sperm density （mean difference （MD）： 10.60, 95% confidence interval （Cl）： 1.92-19.60） and sperm motility （MD： 9.09, 95% Cl. 4.88-13.30）. Subinguinal and inguinal microsurgery outperformed retroperitoneal open surgery in terms of recurrence （OR： 0.05, 0.06 respectively）. Tauber antegrade sclerotherapy and subinguinal microsurgery were associated with the lowest risk of hydrocele formation. The odds of overall complication, compared with retroperitoneal open varicocelectomy, were lowest for inguinal microsurgery （OR = 0.07, 95% Ch 0.02-0.19）, followed by subinguinal microsurgery （OR = 0.09, 95% CI. 0.02-0.19）. Inguinal and subinguinal micro-varicocelectomy had the highest pregnancy rates, significant increases in sperm parameters, with low odds of complication. These results warrant additional properly conducted randomized controlled clinical studies with larger sample sizes.

关键词： meta-analysis varicocele varicocelectomy

Novel rockburst prediction criterion with enhanced explainability employing CatBoost and nature-inspired metaheuristic technique

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Underground Space 2024年第6期19卷 101-118页

作者： Yingui qiu jian Zhou School of Resources and Safety Engineering Central South UniversityChangsha 410083China

Rockburst is a major challenge to hard rock engineering at great *** and timely assessment of rockburst risk can avoid unnecessary casualties and property *** the existence of various methods for rockburst assessment,there remains an urgent need for a comprehensive and reliable criterion that is easy to both apply and *** a new rockburst criterion based on simple parameters can potentially fill this *** its advantages,this criterion can facilitate a more effective and efficient prediction of rockburst potential,thereby contributing significantly to enhancing safety *** this paper,combined with the internal and external factors of rockburst,four control variables(i.e.,integrity index,stress index,brittleness index,and elastic energy index)were selected to be incorporated into a comprehensive rockburstability index(RBSI).Based on 116 sets of rockburst cases,the rockburst potential was accurately quantified and predicted using the categorical boosting(CatBoost)model and the nature-inspired metaheuristic African vultures optimization algorithm(AVOA).In its performance validation,the criterion achieved the highest accuracy of 90.48%,verifying the reliability and effectiveness of the proposed RBSI ***,an interpretive method was applied to analyze the variable influence on the criterion,facilitating the explanation of predictions and the analysis of the formula’s robustness under different *** general,compared with existing criterion methods involving relevant indicators,the newly proposed RBSI criterion enhances the accuracy of rockburst potential prediction,and it can effectively and swiftly evaluate the preliminary risk of ***,a graphical user interface was developed to provide a clear visualization of the assessment of rockburst potential.

关键词： Rockburst criterion CatBoost Metaheuristic optimization Model interpretation Graphical user interface

Reconstruction of biomimetic ionic channels within covalent organic frameworks for ultrafast and selective uranyl capture

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Science China Chemistry 2024年第10期67卷 3423-3431页

作者： Cheng-Rong Zhang Xiao-Juan Chen Cheng-Peng Niu Cheng Meng Shun-Mo Yi xin Liu Jia-xin Qi qiu-Xia Luo Ru-Ping Liang jian-Ding qiu State Key Laboratory of Nuclear Resources and Environment East China University of TechnologyNanchang 330013China College of Chemistry and Chemical Engineering Nanchang UniversityNanchang 330031China

The efficient extraction of uranium,as the primary component of nuclear energy,holds significant *** inspiration from the charge interaction observed in biological ion channels,we encapsulated negatively charged polystyrene sulfonate(PSS)or sodium polystyrene carboxylate(PVBA)into the nanochannels of amidoxime functionalized covalent organic framework(COF-AO)in-situ to alter the cavity environment of *** synthesized COF-AO-PSS and COF-AO-PVBA are used for ultra-fast and highly selective uranium *** negatively charged PSS/PVBA was confined in the COF-AO channel providing the driving force for uranium transport and blocking other ions,thus creating a highly selective“uranium highway”.Additionally,introducing sulfonate groups or carboxyl groups into COF-AO offers supplementary coordination environments and weak interactions with *** to charge-assisted migration and various interaction mechanisms,both COF-AO-PSS and COF-AO-PVBA exhibit faster adsorption kinetics and higher selectivity compared to COF-AO *** adsorption capacities are 3.8 times and 2.4 times that of COF-AO alone respectively which highlights the necessity for constructing biomimetic ion channels in uranium adsorption *** work presents a bionic adsorbent based on covalent organic frameworks(COFs)for the first time,overcoming environmental and equipment limitations associated with traditional photocatalysis and electrocatalysis methods for uranium capture,opening up new avenues for designing multifunctional materials that mimic biological systems.

关键词： covalent organic frameworks Uranium biomimetic ion-channels adsorption

Semen microbiota in normal and leukocytospermic males

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Asian Journal of Andrology 2022年第4期24卷 398-405页

作者： Ye Yao xin-jian qiu Dong-Sheng Wang Jie-Kun Luo Tao Tang Yun-Hui Li Chun-Hu Zhang Hao Liu Lu Zhou Lin-Lin Zhao Health Management Center The Third Xiangya HospitalCentral South UniversityChangsha 410013China Institute of Integrated Traditional Chinese and Western Medicine Xiangya HospitalCentral South UniversityChangsha 410005China Department of Nephrology Integrated Hospital of Traditional Chinese and Western MedicineSouthern Medical UniversityGuangzhou 510220China Department of Traditional Chinese Medicine Guangdong Second Provincial General HospitalGuangzhou 510220China

Large numbers of microbes can be present in seminal fluid,and there are differences in the semen microbiota between normal and abnormal semen *** evaluate the semen microbiota in patients with leukocytospermia,87 seminal fluid samples,including 33 samples with a normal seminal leukocyte count and 54 samples with leukocytospermia,were obtained for a cross-sectional *** samples with a normal seminal leukocyte count had normal sperm parameters(Control group),and 13 samples with a normal seminal leukocyte count were from asthenozoospermia patients(Ast group).However,32 samples with leukocytospermia were from asthenozoospermia patients(LA group),and only 22 samples with leukocytospermia had normal sperm parameters(Leu group).The 16S ribosomal RNA(rRNA)gene sequencing method was used to sequence the microbiota in the seminal fluid,and multiple bioinformatics methods were utilized to analyze the ***,the results showed that the worse sperm parameters were observed in the leukocytospermia-related *** microbiota analysis found that there was increased alpha diversity in the leukocytospermia-related ***,Proteobacteria,Actinobacteria,and Bacteroidetes were the primary phyla in the seminal *** microbiota profiles,namely,Lactobacillus-enriched and Streptococcus-enriched groups,were identified in this *** majority of the samples in the groups with a normal seminal leukocyte count could be categorized as Lactobacillus-enriched,whereas the majority of the leukocytospermia samples could be categorized as *** study indicated that males with leukocytospermia have worse sperm parameters and a different semen microbiota composition compared to males with a normal seminal leukocyte count.

关键词： 16S rRNA gene sequencing asthenozoospermia leukocytospermia semen microbiota sperm motility

Model-driven path planning for robotic plasma cutting of branch pipe with single Y-groove based on pipe-rotating scheme

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Advances in Manufacturing 2024年第1期12卷 94-107页

作者： Yan Liu qiu Tang xin-Cheng Tian School of Control Science and Engineering Shandong UniversityJinan250061People’s Republic of China Engineering Research Center of Intelligent Unmanned System Ministry of EducationJinan250061People’s Republic of China School of Mechanical and Electronic Engineering Shandong Jianzhu UniversityJinan250101People’s Republic of China

The automatic cutting of intersecting pipes is a challenging task in *** improved automation and accuracy,this paper proposes a model-driven path planning approach for the robotic plasma cutting of a branch pipe with a single ***,it summarizes the intersection forms and introduces a dual-pipe intersection *** on this model,the moving three-plane structure(a description unit of the geometric characteristics of the intersecting curve)is constructed,and a geometric model of the branch pipe with a single Y-groove is ***,a novel mathematical model for plasma radius and taper compensation is ***,the compensation model and groove model are integrated by establishing movable ***,to prevent collisions between the plasma torch and workpiece,the torch height is planned and a branch pipe-rotating scheme is *** the established models and moving frames,the planned path description of cutting robot is provided in this novel *** accuracy of the proposed method is verified by simulations and robotic cutting experiments.

关键词： Automatic groove cutting of intersecting pipes Model-driven robot path planning Plasma beam radius and taper compensation

Structural insights into AtABCG25,an angiosperm-specific abscisic acid exporter

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Plant Communications 2024年第1期5卷 284-295页

作者： jian xin Yeling Zhou Yichun qiu He Geng Yuzhu Wang Yi Song jiansheng Liang Kaige Yan Department of Chemical Biology School of Life SciencesSouthern University of Science and TechnologyShenzhen 518055China Institute of Plant and Food Science Department of BiologySchool of Life SciencesSouthern University of Science and TechnologyShenzhen 518055China Max Planck Institute of Molecular Plant Physiology Potsdam-GolmGermany Institute for Biological Electron Microscopy Southern University of Science and TechnologyShenzhenGuangdongChina

Cellular hormone homeostasis is essential for precise spatial and temporal signaling responses and *** acid(ABA)plays pivotal roles in orchestrating various developmental and stress re-sponses and confersfitness benefits over ecological and evolutionary timescales in terrestrial *** ABA level is regulated by complex processes,including biosynthesis,catabolism,and ***25 is thefirst ABA exporter identified through genetic screening and affects diverse ABA *** the structural basis of ABA export by ABCG25 is critical for further manipulations of ABA homeostasis and *** used cryo-electron microscopy to elucidate the structural dynamics of AtABCG25 and successfully characterized different states,including apo AtABCG25,ABA-bound AtABCG25,and ATP-bound AtABCG25(E232Q).Notably,AtABCG25 forms a homodimer that fea-tures a deep,slit-like cavity in the transmembrane domain,and we precisely characterized the critical residues in the cavity where ABA *** binding triggers closure of the nucleotide-binding domains and conformational transitions in the transmembrane *** show that AtABCG25 belongs to a conserved ABCG subfamily that originated during the evolution of *** subfamily neofunctionalized to regulate seed germination via the endosperm,in concert with the evolution of this angio-sperm-specific,embryo-nourishing ***,thesefindings provide valuable insights into the intricate substrate recognition and transport mechanisms of the ABA exporter AtABCG25,paving the way for genetic manipulation of ABA homeostasis and plantfitness.

关键词： AtABCG25 abscisic acid ABC transporters cryo-EM structure

Meta-analysis of transarterial chemoembolization combined with cryoablation vs transarterial chemoembolization alone for≥5 cm hepatocellular carcinoma

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World Journal of Gastrointestinal Oncology 2024年第6期16卷 2793-2803页

作者： Jie-Fei Cheng qiu-Lian Sun Ling Tang xin-jian Xu Xiang-Zhong Huang Department of Radiology The Fifth People’s Hospital of TaizhouTaizhou 225300Jiangsu ProvinceChina Department of Radiology The Fifth People’s Hospital of SuzhouSuzhou 215100Jiangsu ProvinceChina Department of Radiology The Fourth People’s Hospital of TaizhouTaizhou 225300Jiangsu ProvinceChina Department of Interventional Radiology Jiangyin People HospitalJiangyin 214400Jiangsu ProvinceChina

BACKGROUND Hepatocellular carcinoma(HCC)ranks sixth globally in cancer incidence and third in mortality ***,over 70% of HCC patients forego the opportunity for curative surgery or liver transplantation due to inadequate physical examinations,poor physical condition,and limited organ availability upon *** guidelines endorse transarterial chemoembolization(TACE)as the frontline treatment for intermediate to advanced-stage ***(CRA)is an emerging local ablative therapy increasingly used in HCC *** studies suggest that combining CRA with TACE offers complementary and synergistic effects,potentially improving long-term survival ***,the superiority of combined TACE+CRA therapy over TACE alone for HCC lesions equal to or exceeding 5 cm requires further *** To compare the efficacy and safety of TACE combined with CRA vs TACE alone in the treatment of HCC with a diameter of≥5 *** PubMed,EMBASE,Cochrane Library,CNKI,Wanfang,and VIP databases were searched to retrieve all relevant studies on TACE and CRA up to July ***-analysis was performed using RevMan 5.3 *** After screening according to the inclusion and exclusion criteria,6 articles were included,including 2 randomized controlled trials and 4 nonrandomized controlled trials,with a total of 575 patients included in the *** results showed that the objective response rate[odds ratio(OR)=2.56,95%confidence interval(CI):1.66-3.96,P<0.0001],disease control rate(OR=3.03,95%CI:1.88-4.89,P<0.00001),1-year survival rate(OR=3.79,95%CI:2.50-5.76,P<0.00001),2-year survival rate(OR=2.34,95%CI:1.43-3.85,P=0.0008),and 3-year survival rate(OR=3.34,95%CI:1.61-6.94,P=0.001)were all superior to those of the control group;the postoperative decrease in alpha-fetoprotein value(OR=295.53,95%CI:250.22-340.85,P<0.0001),the postoperative increase in CD4 value(OR=10.59,95%CI:8.78-12.40,P<0.00001),and the postoperative decrease in

关键词： Hepatic cancer Cryoablation Chemoembolization Transarterial chemoembolization Meta analysis

Neuronomodulation of Excitable Neurons

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Neuroscience Bulletin 2024年第1期40卷 103-112页

作者： Yizhang Chen Lin Xiao jian qiu Institute of Neuroscience Second Military Medical UniversityShanghai 200433China Institute for Brain Research and Rehabilitation Key Laboratory of BrainCognition and Education Sciences of Ministry of EducationSouth China Normal UniversityGuangzhou 510631China Department of Chemical Physiology and Biochemistry Oregon Health and Science UniversityPortlandOR 97239USA

Neuronomodulation refers to the modulation of neural conduction and synaptic transmission(i.e.,the conduction process involved in synaptic transmission)of excitable neurons via changes in the membrane potential in response to chemical substances,from spillover neuro-transmitters to paracrine or endocrine hormones circulating in the *** can be direct or indirect,depending on the transduction pathways from the ligand binding site to the ion pore,either on the same molecule,*** ion channel,or through an intermediate step on different *** major players in direct neurono-modulation are ligand-gated or voltage-gated ion *** key process of direct neuronomodulation is the binding and chemoactivation of ligand-gated or voltage-gated ion channels,either orthosterically or allosterically,by various *** neuronomodulation involves metabotropic receptor-mediated slow potentials,where steroid hormones,cytokines,and chemokines can implement these *** neuronomodulation is of great significance for understanding the physiological mechanisms of brain function,and the occurrence and treatment of diseases.

关键词： Neuron Membrane potential Excitability Chemoactivation Neuronomodulation