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Design of low-energy transfer from lunar orbit to asteroid in the Sun-Earth-Moon system

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Acta Mechanica Sinica 2014年第6期30卷 966-972页

作者： ya-min wang Dong Qiao Ping-Yuan Cui School of Aerospace Engineering Beijing Institute of Technology Key Laboratory of Dynamics and Control of Flight Vehicle Ministry of Education

Asteroid exploration trajectories which start from a lunar orbit are investigated in this *** is assumed that the probe departs from lunar orbit and returns to the vicinity of Earth,then escapes from the Earth by performing a perigee maneuver.A low-energy transfer in Sun-EarthMoon system is ***,the feasible region of lowenergy transfer from lunar orbit to perigee within 5 000 km height above the Earth surface in Sun-Earth-Moon system is calculated and *** transfer types are found,i.e.,large maneuver and fast transfers,small maneuver and fast transfers,and disordered and slow *** of feasibility trajectories belong to the first two ***,the lowenergy trajectory leg from lunar orbit to perigee and a heliocentric trajectory leg from perigee to asteroid are patched by a perigee *** optimal full-transfer trajectory is obtained by exploiting the differential evolution ***,taking 4179 Toutatis asteroid as the target,some low-energy transfer trajectories are obtained and analyzed.

关键词： Lunar orbit Asteroid exploration Low-energy transfer Sun-Earth-Moon system

Microdissection testicular extraction for a patient with transverse testicular ectopia and testicular fusion

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Asian Journal of Andrology 2018年第3期20卷 306-307页

作者： Chen Chen Yi-Chun wang ya-min wang Chao Qin Ning-Hong Song 0000 China.

Dear Editor, Transverse testicular ectopia （TTE） is a rare condition whereby both testes migrate toward the same hemiscrotum. Most of the cases （65%） are diagnosed intraoperatively during an inguinal hernia repai...

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Losartan improves erectile function through suppression of corporal apoptosis and oxidative stress in rats with cavernous nerve injury

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Asian Journal of Andrology 2019年第5期21卷 452-459页

作者： Yi wang Xiang-Hu Meng Qi-Jie Zhang ya-min wang Chen Chen Yi-Chun wang Xiang Zhou Cheng-Jian Ji Ning-Hong Song Department of Urology The First Affiliated Hospital of Nanjing Medical UniversityNanjing 210029China

This study aimed to investigate the functional and morphological changes in the corpus cavernosum after cavernous nerve(CN)injury or neurectomy and then reveal whether treatment with the angiotensin II Type 1 receptor antagonist losartan would improve erectile function as well as its potential mechanisms.A total of 48 10-week-old Sprague-Dawley male rats,weighing 300-350 g,were randomly divided into the following four groups(n=12 per group):sham operation(Sham)group,bilateral cavernous nerve injury(BOND group,losartaretreated BCNI(BCNI+Losartan)group,and bilateral cavernous neurectomy(Neurectomy)*** was administered once daily by oral gavage at a dose of 30 mg kg^-1 day^-1 for 4 weeks starting on the day of *** BCNI and the Neurectomy groups exhibited decreases in erectile response and increases in apoptosis and oxidative stress,compared with the Sham *** with losartan could have a modest effect on erectile function and significantly prevent corporal apoptosis and oxidative stress?The phospho-B-cell lymphoma 2(Bcl-2)-associated death promoter(p-Bad)/Bad and phospho-the protein kinase B(p-AKT)/AKT ratios were substantially lower,while the Bcl-2-associated X protein(Bax)/Bcl-2 ratio,nuclear factor erythroid 2-related factor 2(Nrf2)/Kelch-like ECH-associated protein 1(Keap-1),transforming growth factor-p 1(TGF-pi)and heme oxygenase-1(HO-1)levels,and caspase-3 activity were higher in the BCNI and Neurectomy groups than in the Sham *** 4 weeks of daily administration with losartan,these expression levels were remarkably attenuated compared with the BCNI *** together,our results suggested that early administration of losartan after CN injury could slightly improve erectile function and significantly reduce corporal apoptosis and oxidative stress by inhibiting the Akt/Bad/Bax/caspase-3 and Nrf2/Keap-1 pathways.

关键词： angiotensin II apoptosis erectile dysfunction fibrosis losartan oxidative stress

Synthesis and Crystal Structure of a Novel Heptanuclear Ruthenium- and Sodium-containing Polyoxomolybdate [{Na(H_2O)_3}_2{Ru(dmso)_3}_2(MoO_4)_3]·_3H_2O

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Chinese Journal of Structural Chemistry 2006年第7期25卷 783-788页

作者： HUANG Xi-He XIANG Sheng-Chang FU Rui-Biao SHENG Tian-Lu ZHANG Jian-Jun LI ya-min wang Long-Sheng WU Xin-Tao State Key Laboratory of Structural Chemistry Fujian Institute of Research on theStructure of Matter The Chinese Academy of Sciences Fuzhou Fujian 350002 China

The title compound, [{Na（H2O）3}2lRu（dmso）3}2（MoO4）3]·3H2O, has been obtained by the reaction of Na2MoO4·2H2O with cis-Ru（dmso）4Cl2 in aqueous solution. Its crystal structure was determined by single-crystal X-ray diffraction method. The crystal crystallizes in the triclinic system, space group PI^- with a = 12.3333（3）, b = 12.6289（3）, c = 32.0284（14） A, α = 79.873（7）, β= 87.549（9）, γ = 64.500（4）°, V = 4429.5（2） A^3, Z = 4, Mr = 1358.85, Dc = 2.038 g/cm^3, F（000） = 2696 and μ = 1.874 mm^-1. The compound contains a novel pentanuclear triangle bipyramidal core, [{ Ru（dmso）3 } 2（MoO4）3]^2-, which consists of two { Ru（dmso）3 } ^2＋ fragments and three {μ2-MoO4}^2- units. Furthermore, the dmso ligands bridge the pentanuclear [Ru2Mo3] core and two [Na（H2O）3]^＋ fragments together, forming a neutral heptanuclear ruthenium- and sodiumcontaining polyoxomolybdate.

关键词： synthesis crystal structure ruthenium sodium polyoxomolybdate

Prostate-derived IL-1βupregulates expression of NMDA receptor in the paraventricular nucleus and shortens ejaculation latency in rats with experimental autoimmune prostatitis

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Asian Journal of Andrology 2022年第2期24卷 213-218页

作者： Jie yang Jiao-Chen Luan Jian-Huai Chen Qi-Jie Zhang Jian-Xin Xue ya-min wang Guo-Qing Zhu Ning-Hong Song Zeng-Jun wang Jia-Dong Xia Department of Urology First Affiliated Hospital of Nanjing Medical UniversityNanjing 210008China Department of Andrology Jiangsu Province Hospital of Chinese MedicineAffiliated Hospital of Nanjing University of Chinese MedicineNanjing 210008China Key Laboratory of Cardiovascular Disease and Molecular Intervention Department of PhysiologyNanjing Medical UniversityNanjing 210008China

Experimental autoimmune prostatitis(EAP)-induced persistent inflammatory immune response can significantly upregulate the expression of N-methyl-D-aspartic acid(NMDA)receptors in the paraventricular nucleus(PVN).However,the mechanism has not yet been ***,we screened out the target prostate-derived inflammation cytokines(PDICs)by comparing the inflammatory cytokine levels in peripheral blood and cerebrospinal fluid(CSF)between EAP rats and their *** identifying the target PDIC,qualified males in initial copulatory behavior testing(CBT)were subjected to implanting tubes onto bilateral ***,they were randomly divided into four subgroups(EAP-1,EAP-2,Control-1,and Control-2).After 1-week recovery,EAP-1 rats were microinjected with the target PDIC inhibitor,Control-1 rats were microinjected with the target PDIC,while the EAP-2 and Control-2 subgroups were only treated with the same amount of artificial CSF(aCSF).Results showed that only interleukin-1β(IL-1β)had significantly increased mRNA-expression in the prostate of EAP rats compared to the controls(Pministration of IL-1β***,the Control-1 subgroup showed a gradually shortened EL(P<0.01)and a significantly higher NR1 expression(P=0.004)after homochronous IL-1β***,we identified IL-1βas the primary PDIC which shortens EL in EAP ***,further studies should be conducted to elucidate the specific molecular mechanisms throug

关键词： chronic prostatitis N-methyl-D-aspartic acid receptor paraventricular nucleus premature ejaculation prostate-derived inflammation cytokines sympathetic nervous system

Updated meta-analysis of pancreatic stent placement in preventing post-endoscopic retrograde cholangiopancreatography pancreatitis

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World Journal of Gastroenterology 2015年第24期21卷 7577-7583页

作者： Jin-He Fan Jun-Bo Qian ya-min wang Rui-Hua Shi Cheng-Jin Zhao Department of Gastroenterology Nantong First People’s Hospital Department of Gastroenterology People’s Hospital of Jiangsu Province

AIM: To investigate the efficacy and safety profile ofpancreatic duct(PD) stent placement for prevention of post-endoscopic retrograde cholangiopancreatography(ERCP) pancreatitis(PEP). METHODS: We performed a search of MEDLINE, EMBASE, and Cochrane Library to identify randomized controlled clinical trials of prophylactic PD stent placement after ERCP. Rev Man 5 software provided by Cochrane was used for the heterogeneity and efficacy analyses, and a meta-analysis was performed for the data that showed homogeneity. Categorical data are presented as relative risks and 95% confidence intervals(CIs), and measurement data are presented as weighted mean differences and 95%CIs. RESULTS: The incidence rates of severe pancreatitis, operation failure, complications and patient pain severity were analyzed. Data on pancreatitis incidence were reported in 14 of 15 trials. There was no significant heterogeneity between the trials(I2 = 0%, P = 0.93). In the stent group, 49 of the 1233 patients suffered from PEP, compared to 133 of the 1277 patients in the no-stent group. The results of this meta-analysis indicate that it may be possible to prevent PEP by placing a PD stent. CONCLUSION: PD stent placement can reduce postoperative hyperamylasemia and might be an effective and safe option to prevent PEP if the operation indications are well controlled.

关键词： Pancreatic stent placement Pancreatitis Endoscopic retrograde cholangiopancreatography Post-endoscopic retrograde cholangiopancreatographypancreatitis

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基于RSSI的改进加权质心定位算法

计算机工程与设计 2016年第11期37卷 2865-2868页

作者：王亚民王海英何佩伦西安科技大学理学院陕西西安710054

基于加权算法的权值选择,分析传统三角加权质心定位算法的权值不合理性,提出一种基于三角质心定位与改进的信号强度比值的加权质心定位的混合定位算法,利用近似点(信标节点间的交点)代替信标节点作为顶点,节点间距离的比值代替信号强度... 详细信息

基于加权算法的权值选择,分析传统三角加权质心定位算法的权值不合理性,提出一种基于三角质心定位与改进的信号强度比值的加权质心定位的混合定位算法,利用近似点(信标节点间的交点)代替信标节点作为顶点,节点间距离的比值代替信号强度的比值作为权值。该算法正确体现了不同节点对未知节点的影响程度,有效降低了路径损耗指数变化对定位精度的影响。实验结果表明,该算法提高了定位精度,可以实现区域定位。

关键词：无线定位接收信号强度指示权值距离比值定位精度

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藏-羌聚落交错区耕地坡谱与信息熵变化特征

干旱地区农业研究 2018年第4期36卷 239-245页

作者：张淑杰郭亚琳樊敏王青西南科技大学环境与资源学院四川绵阳621010

以藏-羌聚落交错区为研究单元,提取该地区1999、2009年和2014年耕地空间信息,通过信息图谱与信息熵定量刻画交错区耕地的坡度分异特征,阐明坡耕地利用的合理程度。结果表明:1999-2014年间,藏-羌聚落交错区耕地总量下降显著,≥24°的耕... 详细信息

以藏-羌聚落交错区为研究单元,提取该地区1999、2009年和2014年耕地空间信息,通过信息图谱与信息熵定量刻画交错区耕地的坡度分异特征,阐明坡耕地利用的合理程度。结果表明:1999-2014年间,藏-羌聚落交错区耕地总量下降显著,≥24°的耕地坡谱段递减明显,陡坡耕地耕作率由1999年的83.67%到2009年的71.97%再到2014年的55.03%,发生明显下降;坡度≤14°的耕地坡谱段呈现上升趋势,缓坡耕作率三年分别为16.33%,28.03%和44.97%,说明交错区耕地利用逐渐向坡度缓和的方向移动,缓坡耕地将逐步成为当地的农作物集中分布区。在退耕还林和5·12地震及其次生地质灾害的双重影响下,藏-羌聚落交错区耕地信息熵由1999年的1.253增加为2009年的1.515,进一步增至1.707,呈逐渐增加的态势,这表明缓坡耕地与陡坡耕地的占比差距缩小,耕地在不同分级坡段间的分布趋于均匀,利于当地水土保持。

关键词：坡谱信息熵耕地藏-羌聚落交错区

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包头压缩技术在VoIP中的应用

上海大学学报（自然科学版） 2001年第1期7卷 18-22页

作者：汪亚光汪敏上海大学通信与信息工程学院上海200072

:针对低速 PPP链路上的 Vo IP应用所存在的问题 ,引入了基于 IP/U DP/RTP封装结构的包头压缩方案 ,总结了包头压缩的基本策略 ,并提出了压缩结构的修正建议 ,最后具体分析了包头压缩所带来的带宽收益、时延收益和信道收益 .

关键词：包头压缩 VoIP 低速串行链路会话场景 IP电话