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Geometrical transition properties of vortex cavitation and associated flow-choking characteristics in poppet valves

Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2024年第6期25卷 455-469页

作者： Liang LU Zhongdong LIANG Yuming LIU Zhipeng WANG shohei RYU School of Mechanical Engineering Tongji UniversityShanghai 201804China Frontiers Science Center for Intelligent Autonomous Systems Tongji UniversityShanghai 201210China Technical Research Laboratory Hitachi Construction Machinery Co.Ltd.Tsuchiura 300-0013Japan

Poppet valves have become increasingly significant in ensuring precise digital flow rate and pressure control in hydraulic systems,necessitating a more profound understanding of the geometrical properties of cavitation in them,as well as associated flow-choking *** a comparative analysis with experimentally observed cavity images,we found that large eddy simulation(LES)turbulence modeling effectively replicates the geometrical properties of cavitation in these *** analysis demonstrated that cavitation is generated from vortices that result from the interaction between the notch contracta flow and the surrounding fluid *** in the internal or external vena contracta conditions result in fixed or discrete cavities,and the length-to-diameter ratio serves as a measure of the transition between internal and external vena contracta flow *** study establishes a threshold length-to-diameter ratio of approximately 2 for the tested poppet *** specifically,in notch structures with a smaller valve opening,longer sealing length,and smaller throttling angle(corresponding to a larger length-to-diameter ratio),the liquid-to-vapor transfer process is more evident than that in the reverse direction.A long-standing vapor cavity becomes fixed inside the notch,leading to a more pronounced flow-choking *** contrast,for structures with a smaller length-to-diameter ratio,the cavitation process for discrete vapor cavities is more complete,ensuring fluid flow continuity and significantly reducing the occurrence of the flow-choking phenomenon.

关键词： Poppet valves Vena contracta Vortex flow Vapor cavity Flow-choking

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A comparison of the efficacy of dutasteride on reducing lower urinary tract symptoms among patients with small versus large benign prostatic hyperplasia

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Current Urology 2024年第3期18卷 199-202页

作者： Kazuyoshi Shigehara Yuki Kato shohei Kawaguchi Kouji Izumi Yoshifumi Kadono Atsushi Mizokami Department of Urology Kanazawa University Graduate School of Medical ScienceKanazawaIshikawaJapan

Background Only a few reports have currently studied the efficacy of dutasteride in patients with small benign prostatic hyperplasia(BPH).We investigated the efficacy of dutasteride on reducing lower urinary tract symptoms among *** and methods A total of 81 patients with BPH who completed 52weeks of 0.5?mg dutasteride treatment were *** patient filled out the International Prostatic Symptom Score(IPSS)and overactive bladder symptom score(OABSS)at baseline and at the 6-and 12-month follow-up *** testosterone,prostate-specific antigen,adenoma/prostate volume(PV),uroflowmetry analysis,and postvoid residual volume were evaluated at baseline and at the 12-month follow-up *** enrolled patients were divided into 2 groups according to PV at *** groups were as follows:Group A(PV≥30 mL)and Group B(PV<30 mL).Results Groups A and B had mean PVs of 52.1 and 23.6 mL and mean IPSS scores of 16.7 and 14.4,*** A had significantly higher OABSS and prostate-specific antigen levels at baseline than Group B,while no significant differences in any other baseline characteristics was *** dutasteride treatment,adenoma volume and PV decreased significantly,while testosterone level showed a significant increase in both *** A showed significant improvements in the total IPSS,voiding and storage subscore of the IPSS,OABSS,maximum flow rate,and postvoid residual *** B,on the other hand,also showed significant improvements only in the total IPSS,voiding subscore of the IPSS,and maximum flow *** The present study suggests a possible beneficial effect of dutasteride treatment on the reduction of lower urinary tract symptoms in patients with small and large ***,the effectiveness of dutasteride was limited compared to patients with large BPH(PV≥30 mL).

关键词： Benign prostatic hyperplasia Dutasteride Lower urinary tract symptoms Testosterone Voiding dysfunction

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Effects of elafibranor on liver fibrosis and gut barrier function in a mouse model of alcohol-associated liver disease

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World Journal of Gastroenterology 2024年第28期30卷 3428-3446页

作者： Aritoshi Koizumi Kosuke Kaji Norihisa Nishimura shohei Asada Takuya Matsuda Misako Tanaka Nobuyuki Yorioka Yuki Tsuji Koh Kitagawa Shinya Sato Tadashi Namisaki Takemi Akahane Hitoshi Yoshiji Department of Gastroenterology Nara Medical UniversityKashihara 634-8521Japan

BACKGROUND Alcohol-associated liver disease(ALD)is a leading cause of liver-related morbidity and mortality,but there are no therapeutic targets and modalities to prevent ALD-related liver *** proliferator activated receptor(PPAR)α and δ play a key role in lipid metabolism and intestinal barrier homeostasis,which are major contributors to the pathological progression of ***,elafibranor(EFN),which is a dual PPARαand PPARδagonist,has reached a phase III clinical trial for the treatment of metabolic dysfunctionassociated steatotic liver disease and primary biliary ***,the benefits of EFN for ALD treatment is *** To evaluate the inhibitory effects of EFN on liver fibrosis and gut-intestinal barrier dysfunction in an ALD mouse *** ALD-related liver fibrosis was induced in female C57BL/6J mice by feeding a 2.5% ethanol(EtOH)-containing Lieber-DeCarli liquid diet and intraperitoneally injecting carbon tetrachloride thrice weekly(1 mL/kg)for 8 ***(3 and 10 mg/kg/day)was orally administered during the experimental *** and molecular analyses were performed to assess the effect of EFN on steatohepatitis,fibrosis,and intestinal barrier *** EFN effects on HepG2 lipotoxicity and Caco-2 barrier function were evaluated by cell-based *** The hepatic steatosis,apoptosis,and fibrosis in the ALD mice model were significantly attenuated by EFN *** promoted lipolysis and β-oxidation and enhanced autophagic and antioxidant capacities in EtOH-stimulated HepG2 cells,primarily through PPARα***,EFN inhibited the Kupffer cell-mediated inflammatory response,with blunted hepatic exposure to lipopolysaccharide(LPS)and toll like receptor 4(TLR4)/nuclear factor kappa B(NF-κB)*** improved intestinal hyperpermeability by restoring tight junction proteins and autophagy and by inhibiting apoptosis and proinflammatory *** protective effect on intestinal bar

关键词： Liver fibrosis Ethanol Gut barrier function Apoptosis Autophagy Peroxisome proliferator activated receptor

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Himalayas as a global hot spot of springtime stratospheric intrusions:Insight from isotopic signatures in sulfate aerosols

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Research in Cold and Arid Regions 2024年第1期16卷 5-13页

作者： Kun Wang ShiChang Kang Mang Lin PengFei Chen ChaoLiu Li XiuFeng Yin shohei Hattori Teresa L.Jackson JunHua Yang YiXi Liu Naohiro Yoshida Mark HThiemens State Key Laboratory of Cryospheric Science Northwest Institute of Eco-Environment and ResourcesChinese Academy of Sciences(CAS)LanzhouGansu 730000China State Key Laboratory of Isotope Geochemistry Guangzhou Institute of GeochemistryCASGuangzhouGuangdong 510640China University of Chinese Academy of Sciences Beijing 100049China International Center for Isotope Effects Research(ICIER) School of Earth Sciences and EngineeringNanjing UniversityNanjingJiangsu 210023China Frontiers Science Center for Critical Earth Material Cycling State Key Laboratory for Mineral Deposits ResearchSchool of Earth Sciences and EngineeringNanjing UniversityNanjingJiangsu 210023China Department of Chemical Science and Engineering School of Materials and Chemical TechnologyTokyo Institute of Technology4259 Nagatsuta-choMidori-kuYokohamaKanagawa 226-8502Japan Department of Chemistry and Biochemistry University of California San DiegoLa JollaCA 92093-0021USA Earth-Life Science Institute Tokyo Institute of TechnologyMeguro-kuTokyo 152-8551Japan National Institute of Information and Communications Technology KoganeiTokyo 184-8795Japan

Downward transport of stratospheric air into the troposphere(identified as stratospheric intrusions)could potentially modify the radiation budget and chemical of the Earth's surface *** the highest and largest plateau on earth,the Tibetan Plateau including the Himalayas couples to global climate,and has attracted widespread attention due to rapid warming and cryospheric *** studies recognized strong stratospheric intrusions in the Himalayas but are poorly understood due to limited direct evidences and the complexity of the meteorological dynamics of the third ***^(35)S is a radioactive isotope predominately produced in the lower stratosphere and has been demonstrated as a sensitive chemical tracer to detect stratospherically sourced air mass in the planetary boundary ***,we report 6-month(April–September 2018)observation of^(35)S in atmospheric sulfate aerosols(^(35)SO_(4)^(2-))collected from a remote site in the Himalayas to reveal the stratospheric intrusion phenomenon as well as its potential impacts in this *** the sampling campaign,the^(35)SO_(4)^(2-)concentrations show an average of 1,070±980 atoms/m^(3).In springtime,the average is 1,620±730 atoms/m^(3),significantly higher than the global existing data measured so *** significant enrichments of^(35)SO_(4)^(2-)measured in this study verified the hypothesis that the Himalayas is a global hot spot of stratospheric intrusions,especially during the springtime as a consequence of its unique geology and atmospheric *** combined with the ancillary evidences,e.g.,oxygen-17 anomaly in sulfate and modeling results,we found that the stratospheric intrusions have a profound impact on the surface ozone concentrations over the study region,and potentially have the ability to constrain how the mechanisms of sulfate oxidation are affected by a change in plateau atmospheric properties and *** study provides new observational constraints on stra

关键词： Himalayas Stratospheric intrusions Cosmogenic^(35)SO_(4)^(2-) Ozone Atmospheric oxidation

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A preliminary study on rectal dose reduction associated with hyaluronic acid implantation in brachytherapy for prostate cancer

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Asian Journal of Urology 2024年第2期11卷 286-293页

作者： Tairo Kashihara Yuka Urago Hiroyuki Okamoto Mihiro Takemori Hiroki Nakayama shohei Mikasa Tetsu Nakaichi Kotaro Iijima Takahito Chiba Junichi Kuwahara Satoshi Nakamura Weishan Chang Yoshiyuki Matsui Hiroshi Igaki Department of Radiation Oncology National Cancer Center Hospital5-1-1 TsukijiChuo-kuTokyoJapan Radiation Safety and Quality Assurance Division National Cancer Center Hospital5-1-1 TsukijiChuo-kuTokyoJapan Department of Radiological Sciences Graduate School of Human Health SciencesTokyo Metropolitan University7-2-10 Higashi-OguArakawa-kuTokyoJapan Department of Radiological Technology National Cancer Center Hospital5-1-1 TsukijiChuo-kuTokyoJapan Department of Urological Oncology National Cancer Center Hospital5-1-1 TsukijiChuo-kuTokyoJapan

Objectives: Hydrogel spacer (HS) was developed to reduce rectal toxicities caused by radiotherapy, but has been reported to cause major adverse events. Our institute has attempted to introduce a hyaluronic acid (HA) as an alternative spacer. This study aimed to compare rectal doses and geometric distributions between the HS and HA implantation in prostate ***: HS and HA were inserted in 20 and 18 patients undergoing high-dose brachytherapy, respectively. The rectum spacer volumes injected were 10 mL and 22 mL, respectively. In the treatment planning system, 13.5 Gy was administered with common catheter positions. The rectal dose indices were assessed between the spacer groups for dosimetry evaluation. Distances between the prostate and rectum and configurations of the spacers were ***: The mean doses irradiated to 0.1 and 2 mL of the rectum were 10.45 Gy and 6.71 Gy for HS, and 6.73 Gy and 4.90 Gy for HA (p<0.001). The mean minimum distances between the prostate and rectum were 1.23 cm and 1.79 cm for HS and HA, respectively (p<0.05). Geometrical configuration comparisons revealed that HA has a higher ability to expand the space than ***: The rectal dose reduction ability of HA is significantly greater than that of HS, suggesting its potential as a new spacer.

关键词： Brachytherapy Hyaluronicacid Hydrogel Prostaticneoplasm Radiotherapy

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锥阀漩涡空化几何形态变迁与流量饱和特性（英文）

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2024年第6期 455-469页

作者：陆亮梁中栋刘禹明王志鹏 shohei RYU 同济大学机械与能源工程学院同济大学教育部自主智能无人系统前沿科学中心日立建机株式会社技术研究实验室

目的：伴随数字阀在流体控制中日益体现的高端品质，锥阀作为数字阀的主要阀芯结构，其空化与流量饱和问题日益受到重视。本文借助实验与仿真手段，旨在揭示漩涡空化成形机理及其伴随孔口长径比形态变迁的物理规律，以及大尺度空化对流... 详细信息

目的：伴随数字阀在流体控制中日益体现的高端品质，锥阀作为数字阀的主要阀芯结构，其空化与流量饱和问题日益受到重视。本文借助实验与仿真手段，旨在揭示漩涡空化成形机理及其伴随孔口长径比形态变迁的物理规律，以及大尺度空化对流量饱和的影响特性，为高品质锥阀结构设计提供基础依据。创新点：1.应用流束收缩理论定义锥阀固定型与离散型空化的漩涡成型机理与形态变迁规律；2.使用大涡模拟合理复现空化形态并揭示空化对流量饱和的影响规律。方法：1.通过可视化实验，获得锥阀空化的几何形态，并验证数值模型的合理性；2.通过数值计算，研究空化形态随锥阀结构的变化规律；3.利用阀口开度、密封长度和阀芯半锥角三个参数定义长径比无量纲指标，衡量空化形态与流量饱和特性的变化规律。结论：1.锥阀阀口流束内外收缩性质的不同，导致阀口内部固定漩涡与阀口下游离散漩涡的差异，进而形成固定漩涡空化和离散漩涡空化的形态区别。2.使用阀口开度、密封长度和阀芯半锥角定义阀口等效长径比，可用于评价空化几何形态的变迁规律。3.固定漩涡空化对流量饱和的影响程度较大；离散漩涡空化因完整的溃灭过程而对流量饱和影响较小。

关键词：锥阀流束收缩漩涡流动蒸汽空穴流量饱和

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Utility of plasma D-dimer for diagnosis of venous thromboembolism after hepatectomy

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World Journal of Clinical Cases 2024年第2期12卷 276-284页

作者： Taiichiro Miyake Hiroaki Yanagimoto Daisuke Tsugawa Masayuki Akita Riki Asakura Keisuke Arai Toshihiko Yoshida Shinichi So Jun Ishida Takeshi Urade Yoshihide Nanno Kenji Fukushima Hidetoshi Gon shohei Komatsu Sadaki Asari Hirochika Toyama Masahiro Kido Tetsuo Ajiki Takumi Fukumoto Division of Hepato-Biliary-Pancreatic Surgery Department of SurgeryKobe University Graduate School of MedicineKobe 650-0017HyogoJapan

BACKGROUND Venous thromboembolism(VTE)is a potentially fatal complication of *** use of postoperative prophylactic anticoagulation in patients who have undergone hepatectomy is controversial because of the risk of postoperative ***,we hypothesized that monitoring plasma D-dimer could be useful in the early diagnosis of VTE after *** To evaluate the utility of monitoring plasma D-dimer levels in the early diagnosis of VTE after *** The medical records of patients who underwent hepatectomy at our institution between January 2017 and December 2020 were retrospectively *** were divided into two groups according to whether or not they developed VTE after hepatectomy,as diagnosed by contrast-enhanced computed tomography and/or ultrasonography of the lower *** factors,including demographic data and perioperative D-dimer values,were compared between the two *** operating characteristic curve analysis was performed to determine the D-dimer cutoff *** and multivariate analyses were performed using logistic regression analysis to identify significant *** In total,234 patients who underwent hepatectomy were,of whom(5.6%)were diagnosed with VTE following hepatectomy.A comparison between the two groups showed significant differences in operative time(529 vs 403 min,P=0.0274)and blood loss(530 vs 138 mL,P=0.0067).The D-dimer levels on postoperative days(POD)1,3,5,7 were significantly higher in the VTE group than in the non-VTE *** the multivariate analysis,intraoperative blood loss of>275 mL[odds ratio(OR)=5.32,95%confidence interval(CI):1.05-27.0,P=0.044]and plasma D-dimer levels on POD 5≥21μg/mL(OR=10.1,95%CI:2.04-50.1,P=0.0046)were independent risk factors for VTE after *** Monitoring of plasma D-dimer levels after hepatectomy is useful for early diagnosis of VTE and may avoid routine prophylactic anticoagulation in the

关键词： Hepatectomy Malignant tumor Postoperative complication D-dimer Early diagnosis Venous thromboembolism

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高维同位素信号阐明大气硫循环机制

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矿物岩石地球化学通报 2024年第4期43卷 875-882页

作者：服部祥平洪一航孙翔南京大学国际同位素效应研究中心南京210023 南京大学地球科学与工程学院南京210023

大气中硫酸盐(SO42–)气溶胶的形成是大气硫循环的重要组成部分。然而,目前关于SO42–的化学反应生成机制仍不甚清晰。SO42–的稳定同位素信号是追踪其来源和大气氧化反应机制的有效方法。本文对叁氧肆硫同位素解析大气SO42–的研究进... 详细信息

大气中硫酸盐(SO42–)气溶胶的形成是大气硫循环的重要组成部分。然而,目前关于SO42–的化学反应生成机制仍不甚清晰。SO42–的稳定同位素信号是追踪其来源和大气氧化反应机制的有效方法。本文对叁氧肆硫同位素解析大气SO42–的研究进展进行了梳理。SO42–的氧同位素非质量依赖分馏(Mass-independent Fractionation,MIF)信号(Δ17O)是分析SO42–气溶胶生成机制(即氧的来源)的有效手段,就冰芯和大气气溶胶等样品与三维大气化学传输模式的Δ17O值对比,讨论了大气硫循环过程。此外,本文还详细介绍了如何使用叁氧肆硫同位素解析大气硫酸盐气溶胶的生成和形成机制,讨论了其他大气硫循环的同位素测定的研究实例。最后对高维同位素解析大气硫循环机制的未来研究方向进行了展望。

关键词：同位素体大气硫循环气溶胶叁氧同位素肆硫同位素

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Removing fences from sweep motion videos using global 3D reconstruction and fence-aware light field rendering

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Computational Visual Media 2019年第1期5卷 21-32页

作者： Chanya Lueangwattana shohei Mori Hideo Saito Department of Science and Technology Keio University Institute of Computer Graphics and Vision Graz University of Technology

Diminishing the appearance of a fence in an image is a challenging research area due to the characteristics of fences(thinness, lack of texture, etc.) and the need for occluded background restoration. In this paper, we describe a fence removal method for an image sequence captured by a user making a sweep motion, in which occluded background is potentially observed. To make use of geometric and appearance information such as consecutive images, we use two well-known approaches: structure from motion and light field rendering. Results using real image sequences show that our method can stably segment fences and preserve background details for various fence and background combinations. A new video without the fence, with frame coherence, can be successfully provided.

关键词： video fence video repair diminished reality(DR) structure from motion(SfM) light field rendering(LFR)

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Generalized Morrey spaces and trace operator

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Science China Mathematics 2016年第2期59卷 281-336页

作者： NAKAMURA shohei NOI Takahiro SAWANO Yoshihiro Department of Mathematics and Information Science Tokyo Metropolitan University

The theory of generalized Besov-Morrey spaces and generalized Triebel-Lizorkin-Morrey spaces is developed. Generalized Morrey spaces, which Mizuhara and Nakai proposed, are equipped with a parameter and a function. The trace property is one of the main focuses of the present paper, which will clarify the role of the parameter of generalized Morrey spaces. The quarkonial decomposition is obtained as an application of the atomic decomposition. In the end, the relation between the function spaces dealt in the present paper and the foregoing researches is discussed.

关键词： Morrey space trace operator decomposition

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