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素＊-环上非线性保XY-ξYX~＊积

数学学报（中文版） 2014年第4期57卷 775-784页

作者：张芳娟西安邮电大学理学院西安710121 西安外事学院工学院西安710077

设M是包含非平凡投影P的单位素*-环.证明了非线性双射φ:M→M对所有A,B∈M,满足φ(AB-ξBA*)=φ(A)φ(B)—ξφ(B)φ(A)*.若ξ=1,则φ是线性或共轭线性的*-同构;若ξ≠1,则φ是*-环同构,且对所有A∈M,有φ(ξA)=ξφ(A).

关键词： XY-ξYX*积非线性素*-环标准讨论

Malignant ovarian tumors complicating pregnancy: a clinicopathological study of twenty-one cases

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生殖医学杂志 2004年第Z1期13卷 1-7页

作者： Zhao Xue-ying Huang Hui-fang Lian Li-juan Department of Obstetrics & Gynecology Peking Union Medical College Hospital Peking Union Medical College Chinese Academy of Medical Sciences Beijing 100730 China Department of Obstetrics & Gynecology Peking Union Medical College Hospital Peking Union Medical College Chinese Academy of Medical Sciences Beijing 100730 China Department of Obstetrics & Gynecology Peking Union Medical College Hospital Peking Union Medical College Chinese Academy of Medical Sciences Beijing 100730 China

Objective: To study the clinicopathological characters of malignant ovarian tumors during pregnancy. The rationale for appropriate management was ***: Twenty-one cases of malignant ovarian tumors complicating pregnancy treated between 1985 and 2002 were reviewed retrospectively. In reference with the reports from the current literatures, the rationale of the treatment for the best outcome of both mother and child was ***:In the patients reviewed, 9 were found with malignant germ cell tumors of the ovary, 6 with low malignant potential tumors, 4 with invasive epithelial tumors, and 2 with sex cord-stromal tumors. Sixteen (76.2 %) of the patients diagnosed in stage I, and all had achieved complete response to the treatment. Three of the four patients in advanced stage died, of which two were invasive epithelial cancers and one stage Ⅳ endodermal sinus tumor. All patients had surgery, and fourteen of them got conservative surgery. All sixteen patients accepted for chemotherapy took adjuvant chemotherapies after abortions or deliveries. Fourteen healthy live births were recorded in this group and there were no documented birth defects, but one died of respiratory distress ***: The managements of malignant ovarian cancers during pregnancy differed in different histological types. In ovarian borderline tumors and malignant germ cell tumors including stage Ⅰ, Ⅱ, and Ⅲ, surgery can be conservative. For advanced epithelial cancers, aggressive surgery should be instituted. Chemotherapy could be considered for the malignant germ cell tumor during the second and third trimester. Ovarian borderline tumors should not take *** cancer should be given combination platinum-based chemotherapy. Hysterectomy during pregnancy is rarely indicated unless it contributes significantly to tumor debulking, and pregnancy often could be allowed to continue until near-term.

关键词： Ovarian cancer Pregnancy Prognosis

基于FRFT的α域-包络曲线的雷达信号特征提取及自动分类

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电子与信息学报 2009年第8期31卷 1892-1897页

作者：司锡才柴娟芳哈尔滨工程大学信息与通信工程学院哈尔滨150001

提取和补充新的特征参数是解决复杂体制雷达辐射源信号分选和雷达目标识别难题的有效手段,为此该文提出一种基于FRFT的α域-包络曲线特征向量的提取方法。该方法通过FRFT搜索得到旋转角域的包络曲线函数,提取出该曲线峰值所对应的α值... 详细信息

提取和补充新的特征参数是解决复杂体制雷达辐射源信号分选和雷达目标识别难题的有效手段,为此该文提出一种基于FRFT的α域-包络曲线特征向量的提取方法。该方法通过FRFT搜索得到旋转角域的包络曲线函数,提取出该曲线峰值所对应的α值、峰值大小及包络曲线峰度这3个特征,构造新的特征向量,并以此作为经典参数的补充。同时,采用动态聚类法就所提取的特征向量分选空间雷达辐射源信号。大量的仿真结果表明,提取的新特征具有较好的类内聚敛和类间分离能力,还具有较好的抗噪声性能,证实了新特征向量作为信号分选参数的有效性和可行性。

关键词：雷达目标识别雷达信号分选分数阶傅里叶变换特征提取动态聚类

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基于SRv6的确定性网络服务共享保护方案

通信学报 2021年第10期42卷 32-42页

作者：李硕朋方娟陈肯北京工业大学信息学部北京100124 法国索邦巴黎北大学伽利略理工学院维尔塔纳斯93430

针对现有方法难以实现确定性网络的高效部署和服务保护的问题,提出基于SRv6的确定性网络服务保护架构,以实现确定性网络的高效管控与转发。在此架构下,设计了面向服务的确定性网络服务保护方案,对基于资源共享的服务保护策略进行了建模... 详细信息

针对现有方法难以实现确定性网络的高效部署和服务保护的问题,提出基于SRv6的确定性网络服务保护架构,以实现确定性网络的高效管控与转发。在此架构下,设计了面向服务的确定性网络服务保护方案,对基于资源共享的服务保护策略进行了建模;设计了基于最短路径的启发式算法,通过共享备份路径带宽,优化了网络资源的利用率和时延。实验结果表明,相比于非共享算法,共享保护算法具有明显优势。

关键词：确定性网络分段路由服务保护故障恢复软件定义网络

Factors influencing recovery of left ventricular structure in patients with chronic heart failure

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Chinese Medical Journal 2011年第18期124卷 2868-2873页

作者： DUAN Hong-yan WU Xue-si HAN Zhi-hong GUO Yong-fang fang Shan-juan ZHANG Xiao-xia WANG Chun-mei Department of Cardiology Beijing Anzhen Hospital Capital Medical University Beijing 100029 China

Background Angiotensin converting enzyme （ACE） inhibitors and G-blockers （13B） have beneficial effects on left ventricular （LV） remodeling, alleviate symptoms and reduce morbidity and mortality in patients with chronic heart failure （CHF）. However the correlation between the d osages of ACE inhibitors, βB, and recovery of LV structure remains controversial. Clinical factors associated with recovery of normal ventricular structure in CHF patients receiving medical therapy are poorly defined. Here we aimed to identify variables associated with recovery of normal or near-normal structure in patients with CHF. Methods We recruited 231 consecutive CHF outpatients, left ventricular ejection fraction （LVEF）〈40% and left ventricular end diastolic diameter （LVEDD）〉55/50 mm （male/female）, who were receiving optimal pharmacotherapy between January 2001 and June 2009, and followed them until December 31,2009. They were divided into three groups according to LVEDD and whether they were still alive at final follow-up： group A, LVEDD 〈60/55 mm （male/female）; group B, LVEDD 〉60/55 mm （male/female）; and group C, those who died before final follow-up. Apart from group C, univariate analysis was performed followed by Logistic multivariate analysis to determine the predictors of recovery of LV structure. Results A total of 217 patients completed follow-up, and median follow-up time was 35 months （range 6-108）. Twenty-five patients died during that period; the all-cause mortality rate was 11.5%. Group A showed clinical characteristics as follows： the shortest duration of disease and shortest QRS width, the lowest N-terminal brain natriuretic peptide （NT-proBNP） at baseline, the highest dose of I3B usage, the highest systolic blood pressure （SBP）, diastolic blood pressure （DBP） and the lowest New York Heart Association （NYHA） classification, serum creatinine, uric acid, total bilirubin and NT-proBNP after treatment. Logistic multivariate analysis was performed according to recovery or

关键词： heart failure drug therapy prognosis prognostic factors

Topographic Effect on Geostrophic Adjustment and Frontogenesis

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Advances in Atmospheric Sciences 2001年第4期18卷 524-538页

作者：方娟伍荣生 The Key Laboratory of Mesoscale Sever Weather (MOE) Nanjing University Nanjing

Three conservative principles: potential vorticity, absolute momentum and potential temperature are used to study the influence of topography on the local frontogenesis and geostrophic adjustment, which are induced by the inhomogeneous thermal fields. It is found that the horizontal distribution of the initial potential temperature and its position relative to the mountain play important roles during the geostrophic adjustment and local frontogenesis. The frontogenesis is weakened by the mountain when the initial thermal perturbation is located at the base of the upwind slope. The frontal discontinuity cannot occur unless the horizontal contrast of the initial potential temperature is great enough. Whereas, the situation is opposite when the initial thermal disturbance is main-ly situated near the peak of the mountain. Complementary to the aforementioned cases, the effect of topog-raphy on the frontogenesis depends on the stratification of the flow when the initial thermal disturbance lies at the foot of lee slope. For weak stratification, topography is favorable to the formation of frontal discontinuity, vice versa. This discrepancy is attributed to the difference of subsidence warming, caused by the mountain, when the stratification is either strong or weak. Furthermore, the energy conversion ratio between the kinetic and potential energy during the geostrophic adjustment process is also affected by the topography. In contrast to the flat bottom case, the ratio is reduced (increased) when the initial thermal perturbation lies in the up-wind slope (lee slope). The reason is that the gravity force does negative work in the former case while does positive work in the latter case. Key words Topography - Geostrophic adjustment - Frontogenesis This work was supported by the National Natural Science Foundation of China under Grant 49735180, and by the State Key Basic Program: CHERES.

关键词： Topography Geostrophic adjustment Frontogenesis

Mechanism of Balanced Flow and Frontogenesis

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Advances in Atmospheric Sciences 2001年第3期18卷 323-334页

作者：伍荣生方娟 Lab. of Mesoscale Severe Weather Nanjing University Nanjing 210093 China

The final balanced state of an initial unbalanced flow is discussed with the same method as Vallis (1992). For the two-dimensional, inviscid, rotating and nonlinear model, the final state of the flow depends on the initial conditions. If the initial potential vortcity of the flow is non-uniform, the final state is not necessarily geostrophic. However, for the zero and uniform potential vorticity flow, the final state will satisfy the thermal wind relation when the length scale of the initial disturbance is large enough. Otherwise, discontinuity will occur in the geostrophic solution. In this case, the final balanced state will not be geostrophic any longer and an extended momentum coordinate is introduced to overcome the mult-value problem. Key words Frontogenesis - Geostrophic adjustment - Thermal wind balance - Extended momentum coordinates The work was supported by the National Natural Science Foundation of China (Grant Nos. 49735180 and 40075011) and the State Key Basic Program: CHERES.

关键词： Frontogenesis Geostrophic adjustment Thermal wind balance Extended momentum coordinates

Uterine Cavity-shaped Device Used in China

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Journal of Reproduction and Contraception 2007年第2期18卷 72-85页

作者： Yan CHE Ke-juan fang Wei-jin ZHOU Yong-gang DING Yue-lian SUN Yao-ling HAN Olav Merick Peter Fajans Shanghai Institute of Pla ned Parenthood Research Shanghai 200032 China Department of Reproductive Health and Research World Health Organization

Objective To assess the effectiveness, side effects, and acceptability of copper uterine cavity - shaped intrauterine devices （UCD） with and without indomethacin. Methods We used electronic search and hand search to identify relevant literatures. Included papers were systematically reviewed according to previous established guidelines. Results A total of 39 related papers were identified. Of them, 9papers were included in this review： 4 associated with medicated or non-medicated UCD200 （containing copper 200 mm^2） and 5 associated with medicated or non-medicated UCD300 （containing copper 300 mm^2）. The contraceptive effectiveness, cumulative one-year and two-year continuation rates＇ were similar between medicated UCD200, non-medicated UCD200 and TCu220C. The effectiveness of non-medicated UCD300 was similar to that of TCu220C and TCu200. The effectiveness of medicated UCD300 was similar to that of MLCu375 and TCu220C but lower than that of TCu38OA. The cumulative one-year, three-year and five-year continuation rates were similar between medicated, non-medicated UCD300 and TCu380A or MLCu375. The problem of bleeding was less common among medicated UCD users than among non-medicated devices. Conclusions Uterine cavity-shaped devices should continue to be used in the National Family Planning Proramme. However, priority should be given to the 300 mm^2 copper containing device. A large multicenter randomized comparative trial of UCD300 and TCu380A is needed.

关键词： uterine cavity-shaped device side effect acceptability systematic review contraceptive effectiveness

Endoscopic-ultrasound-guided biliary drainage with placement of electrocautery-enhanced lumen-apposing metal stent for palliation of malignant biliary obstruction:Updated meta-analysis

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World Journal of Gastrointestinal Surgery 2024年第3期16卷 907-920页

作者： Zu-Xiang Peng fang-fang Chen Wen Tang Xu Zeng Hong-juan Du Ru-Xian Pi Hong-Ming Liu Xiao-Xiao Lu Department of Hepatobiliary Surgery Daping HospitalArmy Medical UniversityChongqing 400042China Department of Oncology Chongqing General HospitalChongqing UniversityChongqing 401147China Department of Gastroenterology and Hepatobiliary Surgery People’s Hospital of Fenggang CountyGuizhou 564200Guizhou ProvinceChina Hepatobiliary and Pancreatic Tumor Center Chongqing University Cancer HospitalChongqing 400030China

BACKGROUND Endoscopic ultrasound-guided biliary drainage using electrocautery-enhanced(ECE)delivery of lumen-apposing metal stent(LAMS)is gradually being re-cognized as a viable palliative technique for malignant biliary obstruction after endoscopic retrograde cholangiopancreatography(ERCP)***,most of the studies that have assessed its efficacy and safety were small and *** meta-analyses of six or fewer studies that were published 2 years ago were therefore underpowered to yield convincing *** To update the efficacy and safety of ECE-LAMS for treatment of biliary ob-struction after ERCP *** We searched PubMed,EMBASE,and Scopus databases from the inception of the ECE technique to May 13,*** outcome measure was pooled technical success rate,and secondary outcomes were pooled rates of clinical success,re-intervention,and adverse ***-analysis was performed using a random-effects model following Freeman-Tukey double-arcsine transformation in R soft-ware(version 4.1.3).RESULTS Fourteen eligible studies involving 620 participants were ultimately *** pooled rate of technical success was 96.7%,and clinical success was 91.0%.Adverse events were reported in 17.5%of *** reinter-vention rate was 7.3%.Subgroup analyses showed results were generally *** ECE-LAMS has favorable success with acceptable adverse events in relieving biliary obstruction when ERCP is *** consistency of results across most subgroups suggested that this is a generalizable approach.

关键词： Biliary obstruction Biliary drainage Electrocautery-enhanced lumen-apposing metal stents Endoscopic ultrasound Endoscopic retrograde cholangiopancreatography failure