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Influence of total dissolved gas-supersaturated water on silver carp(Hypophthalmichthys molitrix)

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Water Science and Engineering 2016年第4期9卷 324-328页

作者： Lu Cao rui-feng liang You-cai Tuo Yong Li Ke-feng Li State Key Laboratory of Hydraulics and Mountain River Engineering Sichuan University

Dam discharges over spillways are the main reason for the gas-supersaturated water generated in *** aquatic organisms,especially fish,readily develop gas bubble disease(GBD) in a river with total dissolved gas supersaturation(TDGS).Sometimes,fish will die after a specific exposure period,which negatively affects the biological *** this study,the influence of TDGS on silver carp was *** carp were exposed to gas-supersaturated water with TDGS levels of 140%,135%,130%,125%,120%,and 110%to test the impact of *** silver carp died when the TDGS level was 120%or higher,and all the silver carp exposed to a TDGS level of 140%died within10 *** comparison with the Chinese sucker,Prenant's schizothoracin,and rock carp,silver carp seem less sensitive to *** addition,we tested the catalase(CAT) activity in the muscles and gills of silver carp after they were exposed to gas-supersaturated water with a TDGS level of140%.The CAT activity changed with time;it increased first and then decreased until it was lower than the initial CAT *** results of this study can provide basic data for developing a standard for environmental evaluation.

关键词： Total dissolved gas supersaturation Silver carp CAT activity Gas bubble disease Median lethal time Median lethal concentration

Modeling of thermodynamics of ice and water in seasonal ice-covered reservoir

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Journal of Hydrodynamics 2018年第2期30卷 267-275页

作者： Nan Li You-cai Tuo Yun Deng rui-dong An Jia Li rui-feng liang State Key Laboratory of Hydraulics and Mountain River Engineering Sichuan University Chengdu 610065China

A width-averaged 2-D numerical model for simulating vertical distributions of flow and water temperature in reservoirs with an ice cover is developed. In this model, the 2-D flow and water temperature distributions are solved by the finite volume method with the k-？ turbulent model. The heat conduction in the ice cover is modeled by the vertical heat transfer and the heat exchanges through the air-ice and ice-water interfaces. The model is applied to a 153 km long reservoir in Songhua River and the simulated results are in a good agreement with the field data of both the vertical water temperature and the ice thickness. The simulated results show that the ice cover thickness in the reservoir is not uniform, the maximum thickness appears in the middle reach, the outflow temperature has an obvious variation as compared with the natural temperature, and a buoyant flow occurs in the reservoir surface at the freeze-up and break-up periods. The model can effectively simulate the water temperature and the ice conditions of large reservoirs in cold regions.

关键词： Reservoir ice water temperature ice thickness heat conduction

Global Well-posedness of the Generalized Long-short Wave Equations

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Chinese Quarterly Journal of Mathematics 2006年第4期21卷 538-544页

作者： ZHANG rui-feng liang Hong-wei College of Mathematics and Information Science Henan University Kaifeng 475001 China

In the present paper, we investigate the well-posedness of the global solutionfor the Cauchy problem of generalized long-short wave equations. Applying Kato＇s methodfor abstract quasi-linear evolution equations and a... 详细信息

关键词： the generalized long-short wave equations Kato's method uniformly a prioriestimate global well-posedness

Heat transfer at ice-water interface under conditions of low flow velocities

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Journal of Hydrodynamics 2016年第4期28卷 603-609页

作者：李楠脱友才邓云李嘉梁瑞峰安瑞冬 State Key Laboratory of Hydraulics and Mountain River Engineering Sichuan University

The heat transfer at the ice-water interface is closely related to the hydrodynamic and physical properties of the water *** affects the ice cover thickness and the water temperature underlying the ice *** paper studies the heat transfer from the water to the ice *** on the flume data,a linear relationship between the ice-water heat transfer coefficient and the flow velocity beneath the ice cover is established and the calculated dimensionless ice-water heat transfer coefficient is 1.1×*** empirical relationship can be applied to estimate the ice-water heat transfer of reservoirs,lakes and other freshwater bodies when the flow velocity under the ice cover is in the range of 0.024 m/s-0.110 m/s.

关键词： reservoirs beneath hydrodynamic dimensionless freshwater turbulence turbulent deviation affects thick

A parameter analysis of a two-phase flow model for supersaturated total dissolved gas downstream spillways

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Journal of Hydrodynamics 2016年第4期28卷 648-657页

作者：杨慧霞李然梁瑞峰魏娟张沁 State Key Laboratory of Hydraulics and Mountain River Engineering Sichuan University Chengdu 610065China Sichuan Port and Channel Development Co. Ltd Chengdu 610072 China Laboratory of Hydraulics Chongqing Jiaotong University Chongqing 400074 China

A high concentration of the total dissolved gas（TDG） in a flow downstream high dams may cause the gas bubble disease in *** better understand the spatial distribution of a supersaturated TDG,a numerical simulation approach for determining the TDG concentration is shown to be effective and convenient; however,the determination of the model parameters relies to a great extent on the observed field data,which are scarce but are very sensitive to the accuracy of the *** this regard,determining the source parameter in the TDG transport equation is the primary concern of this *** field data from six different spillways in China are used to calibrate the source parameter.A relationship between the source parameter and the hydrodynamic characteristics is *** inclusion of this relationship in the predictive relationship will enable an accurate and rapid estimation of the source parameter and may help in developing mitigation measures for the TDG supersaturation downstream the spillways.

关键词： downstream dissolved bubble mitigation hydrodynamic inclusion turbulent Chongqing enable turbulence

Shoot drying and its cause in Calamus simplicifolius at Nanmeiling, Hainan, China

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Journal of Forestry Research 2011年第4期22卷 681-684页

作者： LI Rong-sheng YIN Guang-tian YANG Jin-chang ZOU Wen-tao LI Jian-guang ZHANG Shuai JIA rui-feng KOU liang WANG Dong-guang Research Institute of Tropical Forestry Chinese Academy of ForestryGuangzhou 510520 Gaangdong Province P.R. China

Many stems are subject to shoot drying in the plantations of Calamus simplicifolius Wei at the Nanmeiling Base of the Forestry Bureau of Baisha County, Hainan Province. As a palm, stems of C simplicifolius stop growing and later die if the shoots are dry. Generally, shoot drying means reduced cane production and reduced profit for a rattan plantation. We aimed to quantify the incidence of shoot drying and determine its reason. We sampled eight 20 m × 20 m plots in the C simplicifolius plantations. In each plot, we counted stems and categorized them as drying shoot or normal shoot, and mother stem or sucker stem. We measured stem length and categorized them as drying shoot and normal shoot for mother stems. We cut open each shoot-drying stem to determine the cause of drying from drying part to fresh part. The frequency of mother stems （259 stem·ha^-1）, was significantly lower than sucker stems （588 stem·ha^-1）. The percentage of shoot drying was 33.8% for mother stems, not significantly higher than that for sucker stems （18,9%）. The mother shoot stems were significantly shorter if they were drying than if normal. 80% of stems with a drying shoot were hollow within the leaf sheath, whereas 10% hosted lively mature larvae （one larvae per shoot） and 10% hosted several lively young larvae. Mature larvae were identified as the Red Palm Weevil, Rhynchophorus ferrugineus Oliver. To confirm the present of the weevil, three pheromone traps for the weevil were set up in the plantations and adult weevils were trapped on the next day and identified as the Red Palm Weevil. We conclude that shoot drying of C. simplicifolius is probably caused by the Red Palm Weevil.

关键词： Calamus simpliciJolius rattan shoot drying Red Palm Wee-vil Rhynchophorus ferrugineus

Posttraumatic stress symptoms among Chinese university students during the COVID-19 pandemic:Prevalence,correlates,and mental health help-seeking

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World Journal of Psychiatry 2025年第1期15卷 145-152页

作者： rui-Yao Wu Lin-feng Ge Bao-liang Zhong Department of Psychiatry The Affiliated Wuhan Mental Health CenterTongji Medical College of Huazhong University of Science&TechnologyWuhan 430012Hubei ProvinceChina Department of Psychiatry Wuhan Mental Health CenterWuhan 430012Hubei ProvinceChina

BACKGROUND Revisiting the epidemiology of posttraumatic stress symptoms(PTSSs)among university students during the coronavirus disease 2019(COVID-19)pandemic as well as understanding the mental health help-seeking behavior of individuals with PTSSs has critical implications for public mental health strategies in future medical *** To investigate the prevalence and correlates of PTSSs among university students during the first wave of the COVID-19 pandemic in China and to examine mental health help-seeking behaviors among these *** A total of 2507 Chinese university students were recruited via snowball *** students completed the Seven-item Screening Scale for Post-traumatic Stress Disorder during the first wave of the COVID-19 pandemic in ***-graphic characteristics,pandemic-related characteristics,and mental health help-seeking behaviors of students with PTSSs were also *** The prevalence of PTSSs among the participants was 28.0%.Seven significant correlates of PTSSs were identified(odds ratio=1.23-3.65,P≤0.024):Female sex,being 19 years old or older,living with others or alone,a low level of family economic status,fair or poor interpersonal relationships,severe or very severe local pandemic,and having family members diagnosed with ***,only 3.28%of the students with PTSSs reported seeking help from mental health *** the 23 students who sought help from mental health specialists,13 opted for online or telephone-based psychological *** Our data suggest that there was a high risk of PTSSs among university students and a high level of unmet mental health needs during the COVID-19 *** delivery of mental health services online or via telephone is a promising approach to address these unmet needs.

关键词： Posttraumatic stress symptoms University students COVID-19 Mental health help-seeking China

Association between autoimmune gastritis and gastric polyps:Clinical characteristics and risk factors

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World Journal of Gastrointestinal Oncology 2025年第1期17卷 73-87页

作者： Jing-Zheng Jin Xiao liang Shu-Peng Liu rui-Lan Wang Qing-Wei Zhang Yu-feng Shen Xiao-Bo Li Division of Gastroenterology and Hepatology Renji HospitalShanghai Jiao Tong University School of MedicineShanghai 200127China Division of Gastroenterology and Hepatology Shanghai Institute of Digestive DiseasesShanghai 200001China Division of Gastroenterology and Hepatology Renji Hospital Affiliated to Shanghai Jiao Tong University School of MedicineShanghai 200127China Division of Gastroenterology and Hepatology Sichuan Armed Police Corps HospitalLeshan 610041Sichuan ProvinceChina Division of Gastroenterology and Hepatology NHC Key Laboratory of Digestive DiseasesRenji HospitalShanghai Jiao Tong University School of MedicineShanghai 200127China Department of Gastroenterology Renji Hospital Affiliated to Shanghai Jiao Tong University School of Medicine Shanghai Institute of Digestive DiseasesShanghai 200127China

BACKGROUND The relationship between autoimmune gastritis(AIG)and gastric polyps(GPs)is not well *** To explore the clinical characteristics and risk factors of AIG with GPs in *** This double center retrospective study included 530 patients diagnosed with AIG from July 2019 to July *** collected clinical,biochemical,serological,and demographic data were of each *** regression analyses,both multivariate and univariate,were conducted to pinpoint independent risk factors for GPs in patients with AIG *** operating characteristic curves were utilized to establish the optimal cutoff values,sensitivity,and specificity of these risk factors for predicting GPs in patients with *** Patients with GPs had a higher median age than those without GPs[61(52.25-69)years vs 58(47-66)years,P=0.006].The gastrin-17 levels were significantly elevated in patients with GPs compared with those without GPs[91.9(34.2-138.9)pmol/mL vs 60.9(12.6-98.4)pmol/mL,P<0.001].Additionally,the positive rate of parietal cell antibody(PCA)antibody was higher in these patients than in those without GPs(88.6%vs 73.6%,P<0.001).Multivariate and univariate analyses revealed that PCA positivity[odds ratio(OR)=2.003,P=0.017],pepsinogen II(OR=1.053,P=0.015),and enterochromaffin like cells hyperplasia(OR=3.116,P<0.001)were significant risk factors for GPs,while pepsinogen I was identified as a protective *** PCA positivity and enterochromaffin like cells hyperplasia are significant risk factor for the development of GPs in patients with *** gastrin-17 levels may also play a role in this *** findings suggest potential targets for further research and therapeutic intervention in managing GPs in patients with AIG.

关键词： Autoimmune gastritis Gastric polyps Neuroendocrine tumor Risk factors Nomogram

盐藻蛋白酶体亚基PSMD7在鞭毛解聚后的表达分析

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生物技术通报 2017年第3期33卷 93-99页

作者：石科梁瑞峰杨亮河南医学高等专科学校郑州451191 郑州大学细胞生物研究室郑州450008 河南省中医药研究院郑州450004

为了研究盐藻19S蛋白酶体亚基PSMD7和鞭毛解聚的关系,用3-异丁基-1-甲基黄嘌呤(IBMX)诱导盐藻鞭毛解聚,实时荧光定量PCR检测PSMD7在鞭毛解聚后的m RNA表达变化。同时通过原核表达和蛋白纯化得到高纯度的盐藻PSMD7蛋白,制备盐藻PSMD7的... 详细信息

为了研究盐藻19S蛋白酶体亚基PSMD7和鞭毛解聚的关系,用3-异丁基-1-甲基黄嘌呤(IBMX)诱导盐藻鞭毛解聚,实时荧光定量PCR检测PSMD7在鞭毛解聚后的m RNA表达变化。同时通过原核表达和蛋白纯化得到高纯度的盐藻PSMD7蛋白,制备盐藻PSMD7的山羊多克隆抗体,Western blot检测PSMD7蛋白在鞭毛解聚后的表达情况。结果显示IBMX诱导鞭毛解聚后PSMD7的m RNA表达水平增高,其中在鞭毛解聚后30 min达到最大值。成功制备了盐藻PSMD7的山羊多克隆抗体,Western blot结果显示PSMD7蛋白在鞭毛解聚后表达增加,说明蛋白酶体亚基PSMD7参与盐藻鞭毛的解聚。

关键词： PSMD7 蛋白酶体鞭毛解聚