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Integrating Factors and Conservation Theorems of Lagrangian Equations for Nonconservative Mechanical System in Generalized Classical Mechanics

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Communications in Theoretical Physics 2006年第1X期46卷 43-45页

作者： QIAO Yong-Fen zhao shu-hong Department of Mechanical Engineering and Automation Zhejiang Science and Technology University Hangzhou 310018 China Engineering College of Northeast Agricultural University Harbin 150030 China

The conservation theorems of the generalized Lagrangian equations for nonconservative mechanical system are studied by using method of integrating factors. Firstly, the differential equations of motion of system are given, and the definition of integrating factors is given. Next, the necessary conditions for the existence of the conserved quantity are studied in detail. Finally, the conservation theorem and its inverse for the system are established, and an example is given to illustrate the application of the result.

关键词： generalized nonconservative system Lagrangian equation conservation theorem integrating factor

提质培优视域下推动高职教育课堂革命的路径研究

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湖北开放职业学院学报 2024年第2期37卷 178-179,183页

作者：赵书红马青吴震江阴职业技术学院江苏无锡214400

课堂革命秉持“以学生为中心”的理念提出了教师、教学内容、教学方法与评价方式的要求,围绕学生的全人发展和可持续发展进行改革,将学生从被动的状态激活起来。高职院校需要通过提升教师能力做好“课堂革命”人力保障、整合教学内容跟... 详细信息

课堂革命秉持“以学生为中心”的理念提出了教师、教学内容、教学方法与评价方式的要求,围绕学生的全人发展和可持续发展进行改革,将学生从被动的状态激活起来。高职院校需要通过提升教师能力做好“课堂革命”人力保障、整合教学内容跟进“课堂革命”内容、创新课堂教学落实“课堂革命”、多元教学评价绘制课堂学习曲线的举措来推动课堂革命的最终实现,让学习真正发生。

关键词：提质培优高职教育课堂革命创新课堂教学评价

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光钟与氢钟联合的时间尺度算法研究

天文学报 2024年第3期65卷 64-74页

作者：赵书红董绍武白杉杉屈俐俐张继海章宇中国科学院国家授时中心西安710600 中国科学院时间基准及应用重点实验室西安710600 中国科学院大学天文与空间科学学院北京100049

光钟的频率稳定度和不确定度达到了10-18量级,使其有望成为下一代的时间频率标准,并可能用来重新定义国际单位“秒”.时间尺度作为准确、连续标记时间流逝过程的基准,是高精度时间产生的基础.时间尺度的产生需要依赖连续稳定运行的原子... 详细信息

光钟的频率稳定度和不确定度达到了10-18量级,使其有望成为下一代的时间频率标准,并可能用来重新定义国际单位“秒”.时间尺度作为准确、连续标记时间流逝过程的基准,是高精度时间产生的基础.时间尺度的产生需要依赖连续稳定运行的原子钟,而光钟作为实验室原型设备,一般不能连续运行,因此光钟参与时间尺度计算是个难点问题.提出将Vondrak-Cepek组合滤波算法应用在光钟与氢钟联合计算的时间尺度,以解决间歇运行的光钟参与时间尺度计算的难点问题.首先利用氢钟的时差数据,采用ALGOS算法计算获得连续稳定的氢钟时间尺度.其次利用Vondrak-Cepek组合滤波算法将氢钟时间尺度与光钟的数据综合,获得光钟参与计算的联合时间尺度.最终试验结果证明, Vondrak-Cepek组合滤波算法有效提升光钟与氢钟联合时间尺度的性能,该时间尺度与协调世界时(Coordinated Universal Time, UTC)的时间偏差达到亚纳秒量级.

关键词：时间:时间尺度频率稳定度方法:数据分析 Vondrak-Cepek组合滤波算法技术:氢钟光钟

Integrating Factors and Conservation Theorems for the Nonholonomic Singular Lagrange System

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Communications in Theoretical Physics 2007年第5X期48卷 791-794页

作者： zhao shu-hong LIANG Li-Fu QIAO Yong-Fen School of Civil Engineering of Harbin Engineering University Harbin 150001 China Engineering College of Northeast Agricultural University Harbin 150030 China

We present a general approach to the construction of conservation laws for the nonholonomic singular Lagrange system. Firstly, the differential equations of motion of the system are written, the definition of integrating factors is given for the system. Next, the necessary conditions for the existence of the conserved quantity are studied in detail. Finally, the conservation theorem and its inverse are established for the system, an example is given to illustrate the application of the result.

关键词： analytical mechanics singular system integrating factor conserved quantity

Integrating Factors and Conservation Theorems of Nonholonomic Dynamical System of Relative Motion

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Communications in Theoretical Physics 2007年第2期47卷 217-220页

作者： QIAO Yong-Fen zhao shu-hong LI Ren-Jie Engineering College of Northeast Agricultural University Harbin 150030 China Faculty of Science Laiyang Agricultural College Laiyang. 265200 China

The integrating factors and conservation theorems of nonholonomic dynamical system of relative motion are studied. First, the dynamical equations of relative motion of system are written. Next, the definition of integrating factors is given, and the necessary conditions for the existence of the conserved quantities are studied in detail. Then, the conservation theorem and its inverse of system are established. Finally, an example is given to illustrate the application of the result.

关键词： nonholonomic system relative motion integrating factor conservation theorem

Analysis of post-operative endophthalmitis after pars plana vitrectomy： a 10-year experience at a single center

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Chinese Medical Journal 2013年第15期126卷 2890-2893页

作者： SHI Xiang-yu zhao hong-shu WEI Wen-bin Beijing Tongren Eye Center Beijing Tongren Hospital Capital Medical University Beijing Ophthalmology & Visual Sciences Key Laboratory Beijing 100730 China

Background Endophthalmitis can be a devastating complication after pars plana vitrectomy. The incidence of post- vitrectomy endophthalmitis is significantly lower than that of endophthalmitis occurring after other intraocular operations. However, normal post-operative pain and inflammation may mask endophthalmitis and lead to delayed diagnosis and grave visual consequences. This study aimed to summarize the outcomes of cases that underwent pars plana vitrectomy over a 10-year period and to analyze the characteristics of post-vitrectomy endophthalmitis. Methods A retrospective observational case study was conducted on all the cases who underwent pars plana vitrectomy in the Beijing Tongren Hospital between January 1, 2002 and March 31, 2012. All cases of endophthalmitis that occurred during a period of 10 years and 3 months were reviewed, and the possible risk factors, clinical findings, causative organism（s）, and the sources of infection were analyzed. Results Within the 10-year observational period, 14 patients developed endophthalmitis after pars plana vitrectomy. The incidence of post-vitrectomy endophthalmitis （0.05%） was lower than that reported previously from the same center （0.12%）. Staphylococcus epidermidis （five patients, 35.71%） was the most common organism identified in aqueous or vitreous cultures. Eight patients （57.14%） had diabetes mellitus. There was no statistically significant difference （P 〉0.05） in the incidence of endophthalmitis between period 1 （with antibiotic pretreatment） and period 2 （without antibiotic pretreatment）. Surgical procedures for the treatment of endophthalmitis were performed in 10 patients （71.43%）. Conclusions This series of cases showed that the incidence of endophthalmitis after pars plana vitrectomy is lower than what was previously reported in our hospital. A variable degree of corneal edema with relatively normal or mildly increased intraocular pressure was one of the commonly observed characteristics of post-vitrecto

关键词： pars plana vitrectomy endophthalmitis post-operative complication

Effect of the regimen of Gaoshan hongjingtian on the mechanism of poly（ADP-ribose） polymerase regulation of nuclear factor kappa B in the experimental diabetic retinopathy

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Chinese Medical Journal 2013年第9期126卷 1693-1699页

作者： zhao hong-shu SHI Xiang-yu WEI Wen-bin WANG Ning-li Beijing Tongren Eye Center Beijing Tongren Hospital Capital Medical University Beijing Ophthalmology & Visual Sciences Key Laboratory Beijing 100730 China

Background Poly（ADP-ribose） polymerase （PARP） plays an important role in the death of retinal capillary cells in diabetic retinopathy （DR） partly via its regulation of nuclear factor kappa B （NF-κB）. The current study investigated the effect of the regimen of Gaoshan hongjingtian （RG） on the mechanism of PARP regulation of NF-κB, and demonstrated the possible impact of the RG and Gaoshan hongjingtian （Rhodiola sachalinensis, RS） on diabetic retinopathy. Methods Wistar rats were made diabetic by administering streptozotocin. They were then assigned to three groups at random. After 2 months, the three groups of these diabetic rats were treated with RS or RG, or untreated. Analyses of expression levels of PARP, NF-κB, and intercellular adhesion molecule-1 （ICAM-1） in the retinas of rats in different groups were performed by Western blotting and immunohistochemical assays, and mRNA levels of NF-κB and ICAM-1 were determined by real-time polymerase chain reaction （PCR）. In addition, the basement membranes of capillaries in the rats＇ retinas were observed using electron microscopy, and diabetes-induced capillary degeneration （ghost pericytes and acellular capillaries） were quantitated. Results From the third month after the injection of streptozotocin, the diabetic rats were given daily RG, RS or tap water separately. The diabetic rats failed to gain weight compared with normal age-matched rats, whereas their glycated hemoglobin levels were significantly increased. After 5 months, the mRNA levels of NF-KB and ICAM-1 and the protein expression of PARP, NF-κB, and ICAM-1 were significantly increased in the retinas of diabetic rats in the untreated group compared with the nondiabetic controls. After 8 months, the number of degenerated retinal capillaries （ghost pericytes and acellular capillaries） was significantly increased in the diabetic rats in the untreated group compared with normal age-matched rats. RG and RS inhibited diabetes-induced over-expression of PARP, NF-KB,

关键词： Rhodiola sachalinensis Gaoshan hongjingtian diabetic retinopathy poly(ADP-ribose) polymerase nuclear factor kappa B

The differential effects of prostate stromal cells derived from different zones on prostate cancer epithelial cells under the action of sex hormones

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Asian Journal of Andrology 2011年第6期13卷 798-805页

作者： Qi Jiang Bang-Min Han Fu-Jun zhao Yan hong shu-Jie Xia Department of Urology Shanghai First People＇s Hospital Institute of Urology Shanghai Jiao Tong University Shanghai 200080 China

It is well known that prostate cancer （PCa） occurs predominantly in the peripheral zone （PZ）, whereas benign prostatic hyperplasia （BPH） typically develops in the transition zone. To identify possible mechanisms underlying zonal differences, we compared the effects of prostate stromal cells derived from the peripheral zone （PZsc） and the transition zone （TZsc） on a PCa epithelial cell line （PC3） in the presence of sex hormones. First, we observed that androgen receptor （AR） mRNA was more highly expressed in PZsc than TZsc when the cells were treated with dihydrotestosterone （DHT） and β-oestradiol （E2）（P〈0.05）. By ELISA, we looked for differences in the secretion of peptide growth factors from PZsc and TZsc. We found that keratinocyte growth factor （KGF） secretion increased with increasing concentrations of DHT （P〉0.01） and was higher in PZsc than TZsc. Under treatment with DHT plus E2, PZsc secreted more transforming growth factor-β1 （TGF-β1） than TZsc, but this pattern was reversed when the cells were treated with E2 only. With increasing concentrations of DHT, insulin-like growth factor-1 （IGF-1） secretion increased in PZsc but decreased in TZsc. To further characterize the effects of PZsc and TZsc on PC3 cells, we developed a coculture model and performed MTT assays, Western blot analysis and real-time RT-PCR. We found that PZsc promoted PC3 cell proliferation and progression better than TZsc, particularly when treated with 10 nmoll^- 1 DHT plus 10 nmoll^-1 E2. In conclusion, our data suggest that PZsc may have a greater capacity to induce PCa development and progression than TZsc via growth factors regulated by sex hormones. These findings provide possible mechanisms underlying zonal differences in prostate diseases, which may aid the search for novel therapeutic targets for PCa.

关键词： androgen growth factor oestrogen prostate cancer stromal cell

Inducible overexpression of porcine homeobox A10 in the endometrium of transgenic mice

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Journal of Integrative Agriculture 2016年第6期15卷 1338-1344页

作者： LIN Rui-yi WU Di zhao Chang-zhi CHEN Shang-shang XIAO Qian LI Xin-yun zhao shu-hong Key Lab of Agricultural Animal Genetics Breeding and Reproduction Ministry of Education/The Cooperative Innovation Center for Sustainable Pig Production Huazhong Agricultural University Wuhan 430070 P.R China College of Animal Science and Technology Northeast Agricultural University Harbin 150030 P.R.China

Homeobox A10 （HOXA 10） is a well-known transcription factor that plays an important role in directing endometrial differ- entiation and establishing the conditions required for implantation. Interestingly, the expression level of HOXAIO may be associated with litter size. To study the effects of the porcine HOXAIO promoter fragment on the expression of HOXAIO gene in vivo, we generated a transgenic mouse model using pronuclear microinjection, and measured the expression of HOXAIO in the endometrium. There was no difference in the expression level of HOXAIO between transgenic and wild- type mice in the absence of hormone stimulation. However, following treatment with progesterone and estradiol benzoate, the expression level of HOXAIO was significantly increased in transgenic mice compared with that of wild-type mice. Fur- thermore, the litter size of transgenic females was larger than that of wild-type females （7.02±1.73 vs. 6.48＋1.85; P=0.14）. Moreover, the difference of litter size was greater in the later parities （7.33±1.62 vs. 6.37±2.02; P=0.08） compared with the first parity （6.76±1.81 vs. 6.61v1.67; P=0.77） between transgenic and wild-type mice. Therefore, our transgenic mouse model provides exciting insights regarding the actions of HOXAIO and its hormone-inducible promoter in vivo. The present study offers valuable proof of principle to develop transgenic pigs with a hormone-inducible promoter regulating HOXAIO to alter litter size.

关键词： porcine HOXA 10 transgenic mice endometrium