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Quantity versus quality： the sperm war

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Asian Journal of Andrology 2016年第6期18卷 900-901页

作者： shan xiao Laixin Xia Key Laboratory of Zebrafish Modeling and Drug Screening for Human Diseases of Guangdong Higher Education Institutes Department of Cell Biology School of Basic Medical Sciences Southern Medical University Guangzhou 510515 China

The evolution of sperm traits manifests itself prolifically across species, andpostcopulatory sexual selection （PSS）, as executed by the female, accompanies this process. The adaptive significance of some sperm traits （for example, the shape and number of sperms） is well understood. However, the evolution of germ size has not been fully exploited. The most recent study by Lfipold et al.1 reveals that the evolution of longer sperm is driven by the female seminal receptacle and mating frequency in Drosophila, which, in turn, increases the benefits to females. These findings provide a comprehensive interpretation regarding the evolution of sperm size.

关键词： DROSOPHILA-MELANOGASTER SEXUAL SELECTION EVOLUTION COMPETITION ORNAMENTS WEAPONS

上海地区生乳质量监测结果及与奶业发达国家限量标准比较

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中国奶牛 2024年第2期 47-51页

作者：邓波杨晓君王晓旭宋宇迎刘洋马颖清上海市农产品质量安全中心上海201708 上海市动物疫病预防控制中心上海201103

为了解上海地区生乳质量情况及与奶业发达国家的差距,本研究以上海地区22家牧场的生乳样品为研究对象,在2018-2023年上半年期间,共采集3万余批次生乳样品,分别对其进行脂肪、蛋白质、体细胞数、菌落总数4项指标的常态化监测,并进行统计... 详细信息

为了解上海地区生乳质量情况及与奶业发达国家的差距,本研究以上海地区22家牧场的生乳样品为研究对象,在2018-2023年上半年期间,共采集3万余批次生乳样品,分别对其进行脂肪、蛋白质、体细胞数、菌落总数4项指标的常态化监测,并进行统计分析,同时与奶业发达国家的生乳限量标准进行比较。结果表明:生乳中的脂肪平均含量≥3.71%,蛋白质平均含量≥3.25%,均符合我国标准的限值。菌落总数平均值≤2×104CFU/mL,远低于国家标准限值,乳体细胞数平均值总体表现平稳,稳定在20万个/mL左右。经与其他国家生乳限量标准进行比较分析,除法国外,上海地区生乳中脂肪含量均值达到国际水平,菌落总数和体细胞数含量均值均达到其他国家标准,而蛋白质平均含量略低于意大利限量标准。

关键词：生乳质量监测国家标准限值国际水平

Effects of cavitation on vortex-induced vibration of a flexible circular cylinder simulated by fluid-structure interaction method

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Journal of Hydrodynamics 2022年第3期34卷 499-509页

作者： Zhi-jian xiao Shi-hao Yang Cao yu.Zhen Zhang Lei Sun Jiang Lai Yan-ping Huang Key Laboratory for Mechanics in Fluid Solid Coupling Systems Institute of MechanicsChinese Academy of SciencesBeijing100190China Nuclear Power Institute of China Chengdu610041China Beijing Electro-mechanical Engineering Institute Beijing100074China State Key Laboratory of Mechanical Behavior and System Safety of Traffic Engineering Structures Shijiazhuang Tiedao UniversityShijiazhuang050043China

To investigate the effects of the cavitation on the vortex-induced vibration,the flow and the vibration characteristics of a flexible circular cylinder in the non-cavitating and cavitating flows at Re=200 are simulated using a fluid-structure interaction(FSI)solver,developed in the OpenFOAM *** accuracy of the fluid-structure interaction solver is verified using the benchmark *** a freely vibrating circular cylinder,the characteristics of the vortex-induced vibration are determined at different frequency *** frequency lock-in is observed in both the cavitating flow and the non-cavitating flow,and the lock-in frequency range is larger in the cavitating flow with a smaller vibration *** the lock-in frequency range,due to the reduction of the fluid forces and the resonance effects at the dominant frequency,the vibration amplitude is decreased in the cavitating flow,as compared to the non-cavitating ***,the low-density vapor and the cavitation collapse weaken the constraints of the flow and the stability of the shedding vortices,respectively,making the flow around the circular cylinder more sensitive to the structural ***,the lock-in frequency range is larger in the cavitating flow.

关键词： Fluid-structure interaction(FSI) cavitation lock-in frequency vortex-induced vibrations OpenFOAM

CINRAD/SB聚焦线圈与速调管故障诊断、定位与排除实例

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气象水文海洋仪器 2024年第3期41卷 133-136,140页

作者：唐坤汪洋罗天阳韩啸陈珊郑静瑜王黎明湖南省气象技术装备中心长沙410007

为了解决聚焦线圈故障隐蔽、速调管故障诊断复杂的问题,文章在分析速调管、聚焦线圈设计原理的基础上结合CINRAD/SB新一代天气雷达速调管及聚焦线圈组成框图,通过分析关键部件及关键点的指标参数及波形、实测参数及波形,调整关键部件及... 详细信息

为了解决聚焦线圈故障隐蔽、速调管故障诊断复杂的问题,文章在分析速调管、聚焦线圈设计原理的基础上结合CINRAD/SB新一代天气雷达速调管及聚焦线圈组成框图,通过分析关键部件及关键点的指标参数及波形、实测参数及波形,调整关键部件及关键点参数、波形来判断速调管及其外围组件情况,成功分析、定位及排除了CINRAD/SB雷达速调管及聚焦线圈造成的系统高压不准及无回波故障。

关键词： CINRAD/SB 聚焦线圈速调管磁场电源灯丝变压器

Effects of Granule Dendrobii on chronic atrophic gastritis induced by N-methyl-N'-nitro-N-nitrosoguanidine in rats

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World Journal of Gastroenterology 2022年第32期28卷 4668-4679页

作者： yu. Wu yu.Li xiao-Ming Jin Guan-Hai Dai Xuan Chen Ye-Ling Tong Ze-Ming Ren yu.Chen xiao-MinXue Ren-Zhao Wu First College of Clinical Medicine Zhejiang Chinese Medical UniversityHangzhou 310052Zhejiang ProvinceChina Institute of Basic Medicine Zhejiang Academy of Traditional Chinese MedicineHangzhou 310007Zhejiang ProvinceChina College of Basic Medicine Zhejiang Chinese Medical UniversityHangzhou 310052Zhejiang ProvinceChina Stark Neuroscience Research Institute&Department of Anatomy Cell Biology and PhysiologyIndiana University School of MedicineIndianapolisIN 46202United States Department of Experimental Animals Zhejiang Academy of Traditional Chinese MedicineHangzhou 310007Zhejiang ProvinceChina

BACKGROUND Dendrobium officinale is an herb of Traditional Chinese Medicine(TCM)commonly used for treating stomach *** formula of Granule Dendrobii(GD)consists of Dendrobium officinale and American Ginseng(Radix Panacis quinquefolii),and is a potent TCM product in *** treatment with GD can promote gastric acid secretion and alleviate gastric gland atrophy in chronic atrophic gastritis(CAG)requires *** To determine the effect of GD treatment on CAG and its potential cellular *** A CAG model was induced by feeding rats N-methyl-N'-nitro-N-nitrosoguanidine(MNNG)for 12 *** oral administration of low,moderate,and high doses of GD in CAG rats for 8 wk,its effects on body weight,gastric mucosa histology,mucosal atrophy,intestinal metaplasia,immunohistochemical staining of proliferating cell nuclear antigen(PCNA)and B-cell lymphoma-2,and hemoglobin and red blood cells were *** The body weights of MNNG-induced CAG model rats before treatment(143.5±14.26 g)were significantly lower than that of healthy rats(220.2±31.20 g,P<0.01).At the 8th week of treatment,the body weights of rats in the low-,moderate-,and high-dose groups of GD(220.1±36.62 g)were significantly higher than those in the untreated group(173.3±28.09 g,all P<0.01).The level of inflammation in gastric tissue of the high-dose group(1.68±0.54)was significantly reduced(P<0.01)compared with that of the untreated group(3.00±0.00,P<0.05).The number and thickness of gastric glands in the high-dose group(31.50±6.07/mm,306.4±49.32μm)were significantly higher than those in the untreated group(26.86±6.41/mm,244.3±51.82μm,respectively,P<0.01 and P<0.05),indicating improved atrophy of gastric *** areas of intestinal metaplasia were significantly lower in the high-dose group(1.74%±1.13%),medium-dose group(1.81%±0.66%)and low-dose group(2.36%±1.08%)than in the untreated group(3.91%±0.96%,all P<0.01).The expression of PCNA in high-dose group was significantly

关键词： Chronic atrophic gastritis Granule Dendrobii N-methyl-N'-nitro-N-nitrosoguanidine Intestinal metaplasia

Hierarchically porous Beta/SBA-16 with different silica-alumina ratios and the hydrodesulfurization performances of DBT and 4,6-DMDBT

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Petroleum Science 2022年第1期19卷 375-386页

作者： Jin-Lin Mei yu.Shi Cheng-Kun xiao Ao-Cheng Wang Ai-Jun Duan Xi-Long Wang State Key Laboratory of Heavy Oil Processing China University of Petroleum(Beijing)Beijing 102249PR China

Hierarchically porous Beta/SBA-16(BS)composite materials,combining the characteristics of the acidity from the Beta zeolite and the three-dimensional structure from SBA-16,were synthesized successfully through a two-step in-situ assembly hydrothermal crystallization method.A series of Ni Mo catalysts supported on BS with different silica-alumina ratios were *** supports and the corresponding catalysts were characterized by XRD,N_(2) physisorption,^(27)Al MAS NMR,TEM,pyridine-FTIR,Raman,XPS and *** activities of series catalysts were evaluated by the hydrodesulfurization(HDS)performances of dibenzothiophene(DBT)and 4,6-dimethyldibenzothiophene(4,6-DMDBT).It was found that the Beta crystallites were embedded into SBA-16 through silanols accompanied by dealumination on the T3-T9 sites of Beta *** Mo/BS-3 with a silica-alumina ratio of 100 exhibited the highest DBT and 4,6-DMDBT HDS activities at the WHSV value of 10 h^(-1),with the conversions of 95.9%and 86.9%respectively,due to the synergistic effects of the suitable specific surface areas,the relatively large pore size,appropriate acidity,the relatively high sulfidation degree,moderate dispersity and good stacking degree of Mo S;active phases.

关键词： Beta/SBA-16 Dibenzothiophene 4,6-Dimethyldibenzothiophene Hydrodesulfurization

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核桃粕馕产品的研发及其品质分析

粮食与油脂 2024年第5期37卷 74-78页

作者：魏骊霏许晶王晓雨裴龙英吴忠红徐恒新疆理工学院食品科学与工程学院新疆阿克苏843000 新疆农业科学院农产品贮藏加工研究所新疆乌鲁木齐830000 新疆理工学院食品安全与营养实验教学示范中心新疆阿克苏843000

在单因素试验的基础上,通过响应面法优化核桃粕馕的加工工艺,并测定核桃粕馕的质构特性及基本理化指标。结果表明:核桃粕馕的最优工艺参数为以小麦粉质量为基准,核桃粕粉添加量5.5%、植物油添加量8.0%、酵母粉添加量0.9%、食盐添加量1.0... 详细信息

在单因素试验的基础上,通过响应面法优化核桃粕馕的加工工艺,并测定核桃粕馕的质构特性及基本理化指标。结果表明:核桃粕馕的最优工艺参数为以小麦粉质量为基准,核桃粕粉添加量5.5%、植物油添加量8.0%、酵母粉添加量0.9%、食盐添加量1.0%、白砂糖添加量5.0%、水添加量10.0%、牛奶添加量40.0%、鸡蛋添加量15.0%、烘烤温度182℃、烘烤时间10 min。在此条件下制成的馕感官评分达到92.156±0.724,馕的水分、脂肪、蛋白质含量分别为18.69%、25.3%、21.95%。

关键词：核桃粕馕响应面法品质

Active flow control of S-duct by plasma synthetic jet

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2022年第8期23卷 652-668页

作者： Ru-bing LIU xiao-yin MEI Sheng-hui XUE yu.wen LU Zhe-zhe SU Qi LIN School of Aerospace Engineering Xiamen UniversityXiamen 361102China Fujian Key Laboratoryof Plasmaand Magnetic ResonanceResearch Xiamen 361102China

Flow separation and secondary flow in the S-duct of an aircraft engine cause severe pressure loss and airflow distortion at the outlet,lowering engine ***,a serial two-electrode plasma synthetic jet(PSJ)actuator array is used to actively control the flow field in the duct and improve its *** results show that the PSJ significantly increases the wall pressure recovery coefficient,suppresses flow separation,and improves the outlet pressure *** primary and secondary orders of the influencing factors are as follows:control position>jet momentum coefficient>excitation frequency>jet *** best jet control position is near the separation location,and the best jet configuration is the‘Λ’*** higher the jet momentum coefficient and excitation frequency,the better the flow *** wall pressure coefficient increases by up to 127.8%,and the outlet steady pressure distortion index decreases by 9.15%.The control mechanism is the direct energy injection into the flow boundary layer through a high-speed jet and the indirect control effect of the induced streamwise *** the one hand,the PSJ suppresses flow separation by improving the ability of the boundary layer to resist the inverse pressure *** the other hand,it reduces pressure distortion by decreasing the intensity of the secondary flow and weakening the *** study thus provides a new technology for the active control of the flow-field characteristics in an S-duct and has significance for guiding the application of synthetic jet technology in S-ducts.

关键词： S-duct Flow control Plasma synthetic jet(PSJ) Flow separation Pressure distortion

小麦低聚肽制备凝固型酸奶及其发酵特性的研究

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农产品加工 2024年第10期 39-42页

作者：单传龙李欣悦许博能胡晓晴严欣吴萧宿州学院生物与食品工程学院安徽宿州234000

选取3种酶(胃蛋白酶、碱性蛋白酶和风味蛋白酶)对谷朊粉进行水解,将不同酶解时间得到的小麦低聚肽加入酸奶中,代替部分牛奶蛋白(3%),以酸奶的pH值、滴定酸度为指标进行感官评价及质构分析,筛选出促酸奶发酵能力较好的酶解物,然后将小麦... 详细信息

选取3种酶(胃蛋白酶、碱性蛋白酶和风味蛋白酶)对谷朊粉进行水解,将不同酶解时间得到的小麦低聚肽加入酸奶中,代替部分牛奶蛋白(3%),以酸奶的pH值、滴定酸度为指标进行感官评价及质构分析,筛选出促酸奶发酵能力较好的酶解物,然后将小麦低聚肽按分子质量进行超滤膜分离,并评价和比较不同肽段的促酸奶发酵能力。结果表明,用碱性蛋白酶水解小麦面筋蛋白24 h的小麦低聚肽促酸奶发酵能力最佳,其中分子质量为1.5~3.5 kU的肽段极大地缩短酸奶的发酵周期,改善了酸奶的感官结构特性。

关键词：小麦低聚肽酶解凝固型酸奶发酵