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Study on the inflammatory cytokines after heterotopic transplantation of isolated mouse heart preserved in a high-pressured mixed gas chamber

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South China Journal of Cardiology 2015年第2期16卷 122-129,136页

作者：张瑞黄帅 LIU Zhen-ling ZHAO Ming-yi 郑少忆郭惠明陈寄梅庄建朱平 Southern Medical University Division of Cardiac Surgery Guangdong Cardiovascular Institute Guangdong General Hospital Guangdong Academy of Medical Sciences

Background The maintenance of heart viability is important for heart transplantation. Currently, heart preservation is limited to 6 hours of cold ischemic storage. This study explored a new heart preservation method under a high-pressured mixed gas chamber. Methods C57BL/6 male mice were used to establish the model of mice cervical heterotopic heart transplantation. Adult donor mice were randomly divided into three groups subjected to naive operation （Group A）, standard control （Group B） and experimental control （Group C）. The recipient mice were randomly divided into two groups subjected to standard control and experimental control. Group A： hearts were isolated; Group B： hearts were isolated and preserved in HTK solution at 4 ℃ for 8 h and transplanted; Group C： hearts were isolated and preserved in high pressured gas （PO2：3200 hPa ＋ PCO： 800 hPa = 4000 hPa） at 4 ℃ for 8h and transplanted. After transplantation, the state of re-beating and cardiac function were observed for Group B and C. At 24 h after transplantation, samples were collected for HE staining, cardiac cell apoptosis detection by Tunnel staining and analysis of tumor necrosis factor α （TNF-α）, interleukin-1β （IL-1β）, interleukin-6 （IL-6） and interleukin-10 （IL-10） by reverse transcriotion-polymerase chain reaction （RT-PCR）. Results In group C, 15 transplanted hearts were re-beat, while only 6 in Group B. The re-beating rate in Group C was significantly higher than Group B [75.0%（15/20） vs. 30.0%（6/20） ,P = 0.01]. The time of re-beating was significantly different between Group B, and C [（352.35 ± 61.07）s vs. （207.85 ± 71.24） s, P 〈 0.011. HE staining showed that pathologic changes such as ceil edema and inflammatory cell infiltration were more obvious in Group B and C than in Group A, but less obvious in Group C compared with Group B. Tunnel staining showed that Group B had more obvious apoptosis than Group A and C. RT-PCR results showed significant increase of TNF-α, IL-1β and IL-6 expression in Gro

关键词： high-pressured mixed gas preservation carbon monoxide isolated heart preservation cold ischemia and reperfusion injury inflammation apoptosis

Factors associated with the incidence of ectopic pregnancy in women undergoing assisted reproductive treatment

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Chinese Medical Journal 2020年第17期133卷 2054-2060页

作者： Xiao-ying Jin Chao Li Wen Xu Liu Liu Min-ling Wei Hai-yi Fei Jing Li Feng Zhou Song-ying Zhang Assisted Reproduction Unit Department of Obstetrics and GynecologySir Run Run Shaw HospitalZhejiang University School of MedicineHangzhouZhejiang 310016China Key Laboratory of Reproductive Dysfunction Management of Zhejiang Province HangzhouZhejiang 310016China

Background:Ectopic pregnancy(EP)is a common complication in women undergoing assisted reproductive treatment,but the underlying causes for this remain *** study aimed to explore factors affecting the incidence of EP in in vitro fertilization(IVF)/intracytoplasmic sperm injection(ICSI).Methods:This was a retrospective study on the incidence of EP in IVF/ICSI cycles between January 1,2013 and December 31,*** age,infertility diagnosis(tubal factor or not),primary or secondary infertility,type of cycle(frozen-thawed or fresh),type of embryo(s)transferred(cleavage embryo or blastocyst),number of embryos transferred(one,two,or three),previous history of EP,and endometrial combined thickness were analyzed to explore their relationships with the incidence of *** on clinical typing results,the patients were divided into an EP group or a non-EP *** variables were analyzed using Chi-squared test or Fisher exact *** regression analysis was performed to explore their associations with the incidence of ***:The percentage of patients with primary infertility in EP group was significantly lower than that in non-EP group(31.3%vs.46.7%,χ^2=26.032,P<0.001).The percentage of patients with tubal infertility in EP group was also significantly higher than that in non-EP group(89.2%vs.63.6%,χ^2=77.410,P<0.001).The percentages of patients with transfer of cleavage-stage embryo or blastocyst(91.4%vs.84.4%,χ^2=10.132,P=0.001)and different endometrial combined thickness(ECT)(χ^2=18.373,P<0.001)differed significantly between EP and non-EP *** patients who had a previous history of one to four EPs,the percentage of patients undergoing transfer of a cleavage-stage embryo was significantly higher in EP group than that in non-EP group(92.2%vs.77.6%,χ^2=13.737,P<0.001).In multivariate logistic regression analysis,tubal infertility was strongly associated with EP(adjusted odds ratio:3.995,95%confidence interval:2.706-5.897,P<0.001).Conclusi

关键词： Prognostic factor Ectopic pregnancy Tubal factor In vitro fertilization Intracytoplasmic sperm injection

便携式手术机器人主手附加力位移补偿方法研究

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机械工程学报 2018年第17期54卷 62-68页

作者：凌颢王国慧李政李建民易波孔康王树新朱晒红中南大学湘雅三医院长沙410013 天津大学机构理论与装备设计教育部重点实验室天津300350

采用拉格朗日方程和Stribeck摩擦模型,根据便携式手术机器人主手的杆件重力、各关节摩擦力、惯性力对术者真实力感知的影响,建立了含关节摩擦力的动力学模型。基于机器人主手动力学模型,分别建立重力、摩擦力和惯性力三项的补偿模型,通... 详细信息

采用拉格朗日方程和Stribeck摩擦模型,根据便携式手术机器人主手的杆件重力、各关节摩擦力、惯性力对术者真实力感知的影响,建立了含关节摩擦力的动力学模型。基于机器人主手动力学模型,分别建立重力、摩擦力和惯性力三项的补偿模型,通过分析机器人主手力补偿反馈和附加位移的产生原因及补偿原理,提出了相应的补偿反馈力和附加位移补偿方法。通过对初步研究结果进行对比试验,验证该力补偿控制方法可用以平衡主手因自身所带的重力、关节摩擦力和惯性力产生的影响,最终实现术者真实的力感知,提高手术操作精准性。

关键词：便携式手术机器人附加力补偿附加位移补偿

A tunable dual-narrowband band-pass filter using plasma quantum well structure

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Chinese Physics B 2014年第6期23卷 370-374页

作者：戴燚刘少斌王身云孔祥鲲陈忱 College of Electronic and Information Engineering Nanjing University of Aeronautics & Astronautics College of Electronic and Information Egineering Nanjing University of Information Science and Technology

A tunable dual-narrowband pass-band filter is designed. A one-dimensional photonic crystal （1D PC） is comprised of alternate dielectric layer and vacuum layer. Two quantum wells （QWs） as defects can be constructed by sandwiching two plasma slabs symmetrically in the 1D PC, and a dual-narrowband pass-band filter is formed. The conventional finite- difference time-domain （FDTD） method and piecewise linear current density recursive convolution （PLCDRC）-FDTD method are applied to the dielectric and plasma, respectively. The simulation results illustrate that the dual-narrowband frequencies can be tuned by changing the plasma frequency. The pass band interval and the half-power bandwidths （-3-dB band widths） are related to the space interval between two QWs.

关键词： quantum well dual-narrowband pass-band filter plasma

黄丘区坡沟系统不同时间尺度下的侵蚀产沙特征

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水利学报 2013年第11期44卷 1347-1351页

作者：王玲玲姚文艺王文龙黄静西北农林科技大学陕西杨凌710021 黄河水利委员会黄河水利科学研究院河南郑州450003 华北水利水电学院河南郑州450011

以黄土丘陵沟壑区桥沟流域坡沟系统为原型观测对象,利用流域内布设的不同地貌单元大型径流场定位观测设施,分析了坡沟系统不同地貌单元在年、次降雨时间尺度下的侵蚀产沙特征。结果表明,在年时间尺度上,不同地貌单元的侵蚀模数表现为:... 详细信息

以黄土丘陵沟壑区桥沟流域坡沟系统为原型观测对象,利用流域内布设的不同地貌单元大型径流场定位观测设施,分析了坡沟系统不同地貌单元在年、次降雨时间尺度下的侵蚀产沙特征。结果表明,在年时间尺度上,不同地貌单元的侵蚀模数表现为:上半坡<下半坡<梁峁坡<沟谷坡<坡沟系统,水沙在不同地貌单元之间的传递中,径流输沙量往往小于径流输沙能力,径流侵蚀产生多少沙,就能输送多少沙;在次降雨时间尺度上,不同地貌单元侵蚀产沙的峰值可能出现在下半坡、沟谷坡或者坡沟系统,说明黄土丘陵沟壑区不仅在流域尺度上存在着非平衡输沙过程,在坡沟系统同样存在非平衡输沙现象。

关键词：侵蚀产沙时间尺度坡沟系统黄丘区

森林资源培育工程对革命老区县域城乡收入差距的影响

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林业科学 2023年第1期59卷 74-89页

作者：潘丹罗璐薏余异孔凡斌江西财经大学经济学院南昌330013 浙江农林大学生态文明研究院/经济管理学院杭州311300 南京林业大学经济管理学院南京210037

【目的】在推进共同富裕的中国式现代化宏伟目标背景下,探究森林资源培育工程的实施对革命老区县域城乡收入差距的影响及其作用机制,为新时代新征程中推动革命老区及其他欠发达地区的共同富裕和中国式现代化道路提供支持参考。【方法】... 详细信息

【目的】在推进共同富裕的中国式现代化宏伟目标背景下,探究森林资源培育工程的实施对革命老区县域城乡收入差距的影响及其作用机制,为新时代新征程中推动革命老区及其他欠发达地区的共同富裕和中国式现代化道路提供支持参考。【方法】基于2008-2019年中国28省650个革命老区的县级面板数据,运用空间杜宾模型分析革命老区县森林资源培育对城乡收入差距的影响效应,并从收入效应和就业效应两个角度分析其影响机制。【结果】1)森林资源培育工程对革命老区本地区、相邻地区及整体地区的城乡收入差距均为扩大作用。具体而言,表征森林资源培育工程的造林面积每上升1%,会导致革命老区本地区、相邻地区及整体地区的城乡收入差距分别扩大0.035、0.200和0.236。2)森林资源培育工程主要是通过降低革命老区农村居民收入和提高城镇居民收入,从而扩大了整体城乡收入差距。3)机制分析结果表明,由于革命老区生态保护、人力资本、地理区位等方面的限制,森林资源培育工程的收入效应和就业效应释放不明显,使革命老区陷入“森林资源丰富而经济增长缓慢”的“森林资源诅咒”困境,从而增大其城乡收入差距。具体而言,森林资源培育工程对革命老区旅游收入没有影响,收入效应不显著;同时,森林资源培育工程的实施只能带动革命老区农民就业于劳动边际报酬较低的第一产业,而未能提高边际报酬较高的第二和第三产业就业,甚至挤出了第二和第三产业,就业效应不明显。【结论】应从森林保护和区域产业发展相结合、推动地区间联合进行森林资源培育、加强林业和其他产业的协调发展等方面发力,将革命老区森林资源的“绿水青山”优势有效地转变为“金山银山”的经济优势,利用丰富的森林资源降低革命老区城乡收入差距。

关键词：森林资源培育共同富裕城乡收入差距革命老区

Exploiting multi-channels deep convolutional neural networks for multivariate time series classification

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Frontiers of Computer Science 2016年第1期10卷 96-112页

作者： yi ZHENG QiLIU Enhong CHEN Yong GE J. Leon ZHAO School of Computer Science and Technology University of Science and Technology of China Hefei 230027 China Department of Computer Science University of North Carolina at Charlotte Charlotte 28223 USA Department of Information Systems City University of Hong Kong Hong Kong China

Time series classification is related to many dif- ferent domains, such as health informatics, finance, and bioinformatics. Due to its broad applications, researchers have developed many algorithms for this kind of tasks, e.g., multivariate time series classification. Among the classifi- cation algorithms, k-nearest neighbor （k-NN） classification （particularly 1-NN） combined with dynamic time warping （DTW） achieves the state of the art performance. The defi- ciency is that when the data set grows large, the time con- sumption of 1-NN with DTW will be very expensive. In con- trast to 1-NN with DTW, it is more efficient but less ef- fective for feature-based classification methods since their performance usually depends on the quality of hand-crafted features. In this paper, we aim to improve the performance of traditional feature-based approaches through the feature learning techniques. Specifically, we propose a novel deep learning framework, multi-channels deep convolutional neu- ral networks （MC-DCNN）, for multivariate time series classi- fication. This model first learns features from individual uni- variate time series in each channel, and combines information from all channels as feature representation at the final layer. Then, the learnt features are applied into a multilayer percep- tron （MLP） for classification. Finally, the extensive experi- ments on real-world data sets show that our model is not only more efficient than the state of the art but also competitive in accuracy. This study implies that feature learning is worth to be investigated for the problem of time series classification.

关键词： convolutional neural networks time series clas-sification feature learning deep learning

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离散广义系统的严格耗散分析与控制

控制理论与应用 2008年第3期25卷 462-467,474页

作者：李琴靖新张庆灵衣娜东北大学系统科学研究所辽宁沈阳110004

对离散广义系统,考虑了关于二次型供给率严格耗散控制问题.建立了严格耗散与扩展严格正实之间的等价性.利用线性矩阵不等式(LMI),给出了离散广义系统严格耗散的充分必要条件,并着重推导了其成立的严格LMI条件.针对输入向量维数等于状态... 详细信息

对离散广义系统,考虑了关于二次型供给率严格耗散控制问题.建立了严格耗散与扩展严格正实之间的等价性.利用线性矩阵不等式(LMI),给出了离散广义系统严格耗散的充分必要条件,并着重推导了其成立的严格LMI条件.针对输入向量维数等于状态向量维数的系统.分别利用非严格LMI及严格LMI,讨论了状态反馈下的严格耗散控制问题,并给出控制器的设计方法.也讨论了输入向量维数小于状态向量维数的情况.最后通过仿真算例说明所给方法的有效性和普遍性,同时显示了严格LMI条件在耗散控制问题中,比非严格LMI具有的优势.

关键词：离散广义系统耗散控制线性矩阵不等式状态反馈

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胶体粒子表面改性及其对水泥水化的影响

硅酸盐学报 2017年第5期45卷 601-607页

作者：蒋凌飞卢子臣孔祥明蔡熠清华大学土木工程系建筑材料所北京100084

通过乳液聚合制备了表面性质不同的两种阴离子乳液,即C4与CT乳液。C4乳液在制备过程中通过共聚甲基丙烯酸(MAA)使其中聚合物乳液粒子表面带负电荷,而CT乳液不仅共聚相同量的MAA单体,同时在合成中通过共聚异戊烯聚氧乙烯醚(TPEG),在乳液... 详细信息

通过乳液聚合制备了表面性质不同的两种阴离子乳液,即C4与CT乳液。C4乳液在制备过程中通过共聚甲基丙烯酸(MAA)使其中聚合物乳液粒子表面带负电荷,而CT乳液不仅共聚相同量的MAA单体,同时在合成中通过共聚异戊烯聚氧乙烯醚(TPEG),在乳液粒子表面引入非离子聚氧乙烯(PEO)毛梳层。通过水化热测试、颗粒表面电荷滴定、钙离子电极测试、等温吸附测试等实验探讨了两种乳液对水泥水化的影响及其内在机理。结果表明:与C4乳液相比,表面含非离子PEO毛梳层的CT乳液对水泥水化的抑制作用明显减弱;聚合物乳液粒子表面毛梳层不会降低羧基官能团对钙离子的络合能力;非离子PEO毛梳层的引入显著降低了聚合物乳液粒子在水泥颗粒表面的吸附量。两种乳液粒子在水泥颗粒表面吸附性能的差异是导致其对水泥水化不同影响的主要原因。

关键词：聚合物乳液表面电荷水泥水化吸附