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用耦合求解水动力和刚体运动方程方法计算物体的水中弹道

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上海交通大学学报 1987年第5期22卷 41-47,124页

作者：叶取源上海交通大学工程力学系

本文用表面奇点分布法对物体的水中弹道进行了分析和计算。研究表明,物体所受的水动力必须和刚体运动方程耦合求解才能得到收敛的结果。文中还对极高或极低 F_r 数情况下的物体水中运动进行了讨论。最后给出了算例。

关键词：水中弹道出水数值方法边界元方法

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双参数法解轴对称体小攻角斜出水非线性问题

上海交通大学学报 1991年第5期25卷 23-34页

作者：叶取源上海交通大学工程力学系

本文首先引入新算子,将自由面条件改写为便于计算的形式,然后用双参数摄动法和富里埃级数展开法将三维非线性问题化为二维非线性问题求解.数值结果给出了椭球体在斜出水过程中各阶自由面形状和力系数随物体细长比及佛汝德数变化的情况.

关键词：出水自由面非线性水中兵器

Gaussian 小波系在求解N-S方程中的应用

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上海交通大学学报 1997年第12期31卷 102-107页

作者：王诚叶取源何友声上海交通大学工程力学系

利用Ｇａｕｓｓｉａｎ小波变换使Ｌａｐｌａｃｅ算子降价的性质对任意可变区域上的不可压Ｎ－Ｓ方程进行小波变换．在变换域上Ｎ－Ｓ方程变成了一阶波动方程，用特征线法进行首次积分，逆变换后得到物理空间中的积分方程．用算子方程理... 详细信息

利用Ｇａｕｓｓｉａｎ小波变换使Ｌａｐｌａｃｅ算子降价的性质对任意可变区域上的不可压Ｎ－Ｓ方程进行小波变换．在变换域上Ｎ－Ｓ方程变成了一阶波动方程，用特征线法进行首次积分，逆变换后得到物理空间中的积分方程．用算子方程理论讨论了该积分方程解的存在唯一性，并给出了保证解存在唯一的充分条件，得到了Ｎｅｕｍａｎｎ级数的形式解．

关键词： N-S方程高斯小波系小波分析流体力学

玉米醇溶蛋白糖基化产物对DHA微胶囊氧化稳定性的影响

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食品科学 2024年第12期45卷 68-77页

作者：徐雪晗张慧君李萍宋君宇王屈园王若懿宋秘钊齐齐哈尔大学食品与生物工程学院黑龙江省果蔬杂粮饮品工程技术研究中心黑龙江齐齐哈尔161006 上海夺汇网络技术有限公司上海200082 齐齐哈尔大学轻工与纺织学院黑龙江齐齐哈尔161006

为探究糖基化改性玉米醇溶蛋白作为壁材的抗氧化能力,提高藻油在贮藏期间的抗氧化性,利用改性玉米醇溶蛋白作为壁材包埋藻油,对包埋后藻油的储藏稳定性进行分析,并对其货架期进行预测。结果表明,改性玉米醇溶蛋白的最佳工艺条件为糖/蛋... 详细信息

为探究糖基化改性玉米醇溶蛋白作为壁材的抗氧化能力,提高藻油在贮藏期间的抗氧化性,利用改性玉米醇溶蛋白作为壁材包埋藻油,对包埋后藻油的储藏稳定性进行分析,并对其货架期进行预测。结果表明,改性玉米醇溶蛋白的最佳工艺条件为糖/蛋白质量比1∶12、反应时间30 min、超声功率400 W,在此条件下glu-zein的抗脂质过氧化能力达到最高,为72.31%。改性后的玉米醇溶蛋白抗脂质过氧化能力、1,1-二苯基-2-三硝基苯肼自由基清除能力、还原能力、羟自由基清除能力、超氧阴离子自由基清除能力等均有显著提高(P<0.05)。将藻油包埋在改性玉米醇溶蛋白中考察藻油的储藏稳定性,在加速氧化期间,其过氧化值、硫代巴比妥酸反应物值均低于裸藻油及未改性玉米醇溶蛋白包埋的藻油。60℃条件下储藏18 d后,glu-zein包埋的藻油POV较未改性玉米醇溶蛋白低3.68 mmol/kg,较裸藻油低39.14 mmol/kg;室温条件下与未包埋藻油货架期相比延长240 d;同时,改性后的玉米醇溶蛋白包埋的藻油二十二碳六烯酸保留率为96.95%。研究结果可为扩大改性玉米醇溶蛋白作为壁材的抗氧化性及递送易受氧气影响的生物活性物质应用提供理论依据。

关键词：玉米醇溶蛋白糖基化改性藻油二十二碳六烯酸抗氧化性货架期

妊娠期肝内胆汁淤积症患者血清APOA1、LDHA与胎儿生长发育的相关性研究

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中国性科学 2024年第7期33卷 96-99页

作者：韩慧明陈绵平韦秋圆俞江华海口市妇幼保健院检验科海口570203 海口市妇幼保健院妇保科海口570203 陆良县中医医院检验科海口655600

目的探讨妊娠期肝内胆汁淤积症(ICP)患者血清载脂蛋白A1(APOA1)、乳酸脱氢酶A(LDHA)与胎儿生长发育的相关性。方法选取2020年1月至2022年8月海口市妇幼保健院诊治的128例ICP患者作为观察组,同期同一医院产检的64例健康孕妇作为对照组。... 详细信息

目的探讨妊娠期肝内胆汁淤积症(ICP)患者血清载脂蛋白A1(APOA1)、乳酸脱氢酶A(LDHA)与胎儿生长发育的相关性。方法选取2020年1月至2022年8月海口市妇幼保健院诊治的128例ICP患者作为观察组,同期同一医院产检的64例健康孕妇作为对照组。两组均检测血清APOA1、LDHA水平。观察组根据是否存在胎儿生长受限分为受限组(n=27)、未受限组(n=101),分析胎儿生长受限的影响因素及血清APOA1、LDHA水平对胎儿生长受限的评估价值。结果观察组血清APOA1水平、新生儿出生体重低于对照组,血清LDHA水平高于对照组(P<0.05);发病孕周、血清APOA1水平是胎儿生长受限的独立保护因素,血清LDHA水平是胎儿生长受限的独立危险因素(P<0.05);血清APOA1、LDHA水平联合评估胎儿生长受限的曲线下面积(AUC)为0.894,大于血清APOA1、LDHA水平的单独评估价值。结论ICP患者血清APOA1、LDHA水平与胎儿生长发育关系密切,检测二者水平可为临床早期评估胎儿生长受限的发生风险提供参考。

关键词：妊娠期肝内胆汁淤积症载脂蛋白A1 乳酸脱氢酶A 胎儿生长受限

The effect of dietary tryptophan levels on oxidative stress of liver induced by diquat in weaned piglets

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Journal of Animal Science and Biotechnology 2015年第1期6卷 104-110页

作者： Xiangbing Mao Mei Lv Bing Yu Jun He Ping Zheng Jie Yu quyuan Wang Daiwen Chen Animal Nutrition Institute Sichuan Agricultural University Key Laboratory of Animal Disease-Resistance Nutrition Ministry of Education

Oxidative stress can induce abnormal tryptophan metabolism. The present study was mainly conducted to determine the effect of dietary tryptophan levels on oxidative stress in the liver of weaned pigs challenged by diquat. A total of 36 PIC piglets weaned at 21 days of age were randomly allotted to 1 of 3 diets containing dietary tryptophan levels of 0.18, 0.30, and 0A5% for 14 d. On day 8, the piglets were injected intraperitoneally with sterile 0.9% NaCI solution or diquat （10 mg/kg body weight）. During the first 7 d of trial, increasing dietary tryptophan levels enhanced average daily gain （P = 0.09） and average daily feed intake （P = 0.08）, and decreased the feed efficiency （P 〈 0.05） of piglets. The growth performance was decreased by diquat injection （P 〈 0.05）. Diquat injection also decreased the activities of the superoxide dismutase （SOD） and glutathione peroxidase （GPx） in the plasma and liver （P 〈 0.05）, increased plasma malondialdehyde （MDA）（P 〈 0.05） and urea nitrogen （P 〈 0.05） concentrations, and enhanced MDA concentration （P = 0.09） and tryptophan 2,3-dioxygenase （TDO） activity （P = 0.07） in liver of piglets. Increasing dietary tryptophan levels could attenuate the effects of diquat injection on the MDA （P = 0.06） concentration and the activities of SOD （P = 0.09） and GPx （P = 0.05） of the liver, and plasma urea nitrogen （P = 0.06） concentration in the piglet. There was a synergistic role for increasing TDO activity in the liver between dietary tryptophan levels and diquat injection （P 〈 0.05）. These results suggest that increasing dietary tryptophan levels could attenuate the oxidative stress of the liver in weaned piglets intraperitoneally injected with diquat via enhancing the antioxidant capacity.

关键词： Antioxidant capacity Diquat Oxidative stress of livers Tryptophan,Weaned piglets

ANALYTIC METHOD FOR INVERSING THE OPEN BOUNDARY CONDITIONS IN A SEMI-CLOSED SEA AREA—CASE I FOR INVERSING THE TIDAL LEVELS AT OPEN BOUNDARY

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Journal of Hydrodynamics 2004年第5期16卷 590-595页

作者： ZHANGQing-hua YINXun-qiang MAJian quyuan-yuan KeyLaboratoryofMarineScienceandNumericalModeling TheFirstInstituteofOceanographyStateOceanicAdministrationQingdao266061China KeyLaboratoryofMarineScienceandNumericalModeling TheFirstInstituteofOceanographyStateOceanicAdministrationQingdao266061China

In this paper, a computational case was employed to describe thecomputational procedure for inversing the tidal level open boundary conditions using an analyticmethod. The area for finding the solution is a circular area with a circular arc with the openingangle 60°-being the open boundary and the other circular arc being the solid wall *** from the reestablished elliptic partial differential equation satisfied by the tidallevel function, the extended spectrum method was used to derive the general solution of the equationfor the sea of constant depth, and the impermeable solid wall condition (the second class boundarycondition) and the adequately specified open boundary conditions were then applied to determine theundetermined coefficients of the general solution, thus obtaining the tidal level distributionfunction. In this way, both the first and second class boundary values at the solid wall boundarywere obtained. With the above boundary values as the boundary conditions, the tidal level values atthe open boundary were then inversed by means of the general solution of tidal wave equation. Thevalidity of inversion method could be verified by comparing the inversed tidal level distributionswith the originally specified open boundary values.

关键词： semi-closed sea open boundary condition extended spectrum method generalsolution of equation in-version

Infusion of short chain fatty acids in the ileum improves the carcass traits,meat quality and lipid metabolism of growing pigs

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Animal Nutrition 2021年第1期7卷 94-100页

作者： Anran Jiao Hui Diao Bing Yu Jun He Jie Yu Ping Zheng Yuheng Luo Junqiu Luo quyuan Wang Huifen Wang Xiangbing Mao Daiwen Chen Institute of Animal Nutrition Sichuan Agricultural UniversityKey Laboratory for Animal Disease-Resistance Nutrition of China Ministry of EducationKey Laboratory of Animal Disease-resistant Nutrition and Feed of China Ministry of Agriculture and Rural AffairsKey Laboratory of Animal Disease-resistant Nutrition of Sichuan ProvinceYa'an625014China

Short chain fatty acids(SCFA)are the main products of indigestible carbohydrates undergoing bacterial fermentation in the hindgut,which are related to some physiological *** study was designed to investigate the effects of SCFA infusion by ileum on the carcass traits,meat quality and lipid meta-bolism of growing *** a 28-day study,24 growing barrows fitted with a T-cannula in distal ileum were divided into 4 treatments:1)Control,2)antibiotics(AB),3)AB+300 mL of SCFA1 solution(ABS1),4)AB+300 mL of SCFA2 solution(ABS2).The concentrations of acetate,propionate and butyrate in SCFA1 solution were respectively 61.84,18.62 and 12.55 mmol/L,and in SCFA2 were respectively 40.08,15.41 and 9.78 mmol/L The results showed that the SCFA infusion increased the average daily feed intake and average daily gain of pigs(P<0.05).Meanwhile,the SCFA treatments increased longissimus dorsi area(P<0.05)and carcass weight(P=0.058),decreased the drip loss of longissimus dorsi(P=0.059),and reduced serum concentrations of triglyceride,total cholesterol and urea nitrogen(P<0.05).Besides,the SCFA administration inhibited the mRNA expressions of fatty acid synthase(FAS)and acetyl-CoA carboxylase in longissimus dorsi(P<0.05),the mRNA expression of FAS in the liver(P<0.05),and the mRNA expression of hormone-sensitive lipase in abdominal fat(P<0.05).Short chain fatty acid infusion also enhanced the mRNA expression of carnitine palmitoyltransferase-1αin the liver(P<0.05),the mRNA expressions of peroxisome proliferator activated receptor gamma and lipoprotein lipase in abdominal fat(P<0.05),and the mRNA expressions of free fatty acid receptor 2,glucose-6-phosphatase and phosphoenolpyruvate carboxykinase 1 in the colon(P<0.05).These results suggested that SCFA administration in the ileum could improve the carcass traits and meat quality of growing pigs,which was possibly due to the fact that SCFA modulated lipid metabolism.

关键词： Short chain fatty acid Carcass trait Meat quality Lipid metabolism Growing pig

Tannic acid prevents post-weaning diarrhea by improving intestinal barrier integrity and function in weaned piglets

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Journal of Animal Science and Biotechnology 2021年第2期12卷 700-710页

作者： Jie Yu Yanyan Song Bing Yu Jun He Ping Zheng Xiangbing Mao Zhiqing Huang Yuheng Luo Junqiu Luo Hui Yan quyuan Wang Huifen Wang Daiwen Chen Animal Nutrition Institute Sichuan Agricultural UniversityChengdu 611130People’s Republic of China Key Laboratory for Animal Disease-Resistance Nutrition Ministry of Education of ChinaChengdu 611130People’s Republic of China

Background:Tannic acid(TA)is potential to reduce diarrhea in weaning pigs,but knowledge about the influence of TA on intestinal barrier integrity and function is still *** experiment was conducted to investigate the effects of dietary TA supplementation on growth performance,diarrhea rate,intestinal barrier integrity and function of weaned ***:A total of 108 crossbred(Duroc×Landrace×Yorkshire)piglets,with an initial average body weight of 6.60±0.27 kg,were allotted to 3 groups(6 pigs/pen and 6 replicates/group)in a randomized complete block design according to their gender and body *** were fed the basal diet with 0(control,CON),0.2%and 1.0%TA,*** trial lasted for 28 ***:Compared with the CON group,dietary 0.2%and 1.0%TA supplementation didn’t affect ADFI,ADG and F:G(P>0.05),but reduced diarrhea rate,diarrhea index and diarrhea score of piglets(P<0.05),reduced diamine oxidase(DAO)activity and D-lactic acid concentration in serum(P<0.01).The higher occludin expression and localization were observed in the duodenum,jejunum and ileum after supplementation with 0.2%or 1.0%TA(P<0.05).Adding 0.2%TA to diet significantly decreased crypt depth,increased villus height/crypt depth ratio in the duodenum(P<0.05),and dietary 1.0%TA tended to decrease crypt depth(P<0.10)and significantly decreased villus height(P<0.05)of the ***,lower malondialdehyde content in the ileum was detected in the pigs fed 1.0%TA(P<0.05).In the duodenum,both 0.2%and 1.0%TA groups had higher occludin(OCLN)mRNA and 0.2%TA group had higher zonula occludens-2(ZO-2)level(P<0.05).Meanwhile,dietary 1.0%TA supplementation tended to up-regulate OCLN mRNA levels in the jejunum(P<0.10)and 0.2%TA supplementation tended to up-regulate zonula occludens-1(ZO-1)mRNA levels in the ileum(P<0.10).Conclusion:In conclusion,dietary supplementation of 0.2%or 1.0%TA could effectively alleviate postweaning diarrhea without altering growth performance in weaned piglets,wh

关键词： Intestine barrier Post-weaning diarrhea Tannic acid Weaned piglets