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A new cyclostellettamine from sponge Amphimedon compressa

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Chinese Chemical Letters 2007年第8期18卷 947-950页

作者： Nian jun Xu Xue sun xiao jun Yan Key Laboratory of Marine Biotechnology Faculty of Life Science and Biotechnology Ningbo University Ningbo 315211 China

A new compound, 8,8＇-dienecyclostellettamine, was isolated from the marine sponge Amphimedon compressa. Its structure was elucidated by spectroscopic methods including 1D and 2D NMR, UV, IR, ESI-MS, MALDI-MS techniques. It is probably an important precursor of the manzamine alkoids, and also showed vigorous antibacterial activities.

关键词： Amphimedon compressa Antibacterial 8,8'-Dienecyclostellettamine

Analysis of Neutron Double-Differential Cross Sections for n ＋ ^12 C Reaction Below 30 MeV

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Communications in Theoretical Physics 2007年第3X期48卷 534-540页

作者： sun xiao-jun DUAN jun-Feng WANG Ji-Min ZItANG Jing-Shang College of Physics and Electronic Engineering Guangxi Normal University~ Guilin 541004 China China Institute of Atomic Energy P.O. Box 275(41) Beijing 102413 China

Based on the light nucleus reaction model （Nucl. Sci. Eng. 133 （1999） 218）, four aspects （neutron incident energy region, reaction channel analysis, the renewed level schemes and the optical model parameters） of n＋ ^12 C reaction are improved to calculate total outgoing neutron double-dilferential cross sections with modified LUNF code below 30 MeV. The calculated results agree fairly well with the experimental data at En = 14.1 MeV and 18 MeV. The analysis shows that the pre-equilibrium mechanism, which is exactly considered the conservation of energy, momentum and parity, dominates the whole reaction process. The contribution of the neutron emission from 5He to total energy- angular spectra is also considered properly. This modified LUNF code will be a useful tool to set up the file of neutron double-differential crass sections below 30 Me V in the neutron evaluation nuclear data library.

关键词： double-differential cross section pre-equilibrium emission ^5He emission

^5He Emission in Neutron-Induced ^10B Reactions

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Communications in Theoretical Physics 2006年第3X期46卷 527-532页

作者： WANG Ji-Min DUAN jun-Feng YAN Yu-Liang sun xiao-jun ZHANG Jing-Shang China Institute of Atomic Energy P.O. Box 275(41) Beijing 102413 China College of Physics and Electronic Engineering Guangxi Normal University Guilin 541004 China

In n ＋^10B reactions, ^5He cluster emission has been discussed with the updated level scheme and the new optical model parameters. In this paper the reaction channels related to ^5He emission are listed in detail. By using the new reaction model for light nuclei, the double-differential cross sections of total outgoing neutrons for n ＋ ^10 B reactions at En= 14.2 MeV have been calculated, and the results agree fairly well with the measurements. Particularly, in the energy-angular spectra the contribution from the 5He-emission to the total outgoing neutron double-differential cross sections has also been analyzed, and the partial energy-angular spectra of 60° at En= 14.2 MeV have been given. The calculated results indicate that once the 5He emission is taken into account, the fitting with the double-differential measurements of total outgoing neutrons at the low energy region could be improved. Therefore, to consider the ^5He emission properly in the reaction processes of light nuclei is necessary.

关键词： ^ 5He emission double-differential cross section pre-equilibrium emission

Further Analysis of Neutron Double-Differential Cross Section of n ＋ ^16O at 14.1 MeV and 18 MeV

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Communications in Theoretical Physics 2005年第4X期44卷 701-706页

作者： DUAN jun-Feng YAN Yu-Liang WANG Ji-Min sun xiao-jun ZHANG Jing-Shang China Institute of Atomic Energy P.O. Box 275(41) Beijing 102413 China College of Physics and Information Technology Guangxi Normal University Guilin 541004 China

By using a new reaction model for light nuclei, the double-differential cross section of total outgoing neutron with LUNF code for n＋^16O reactions at En=14.1 MeV and 18 MeV have been calculated and analyzed. In this paper the opened reaction channels, which have contribution to emitting the neutrons, are listed in detail. To improve the fitting results the direct inelastic scattering mechanism is involved. The calculating results agree fairly well with the experimental data at E,~ = 14.1 MeV and the deviation from calculated results and experimental data in low energy region at En= 18 MeV has been analyzed. Since the possibility of 5He has been affirmed theoretically [J.S. Zhang, Sci. Chin. G 47 （2004） 137], so 5He emission from n＋ ^16O reaction is taken into account, which plays an important role at the region of the outgoing neutron energy εn〈3 MeV in total outgoing neutron energy-angular spectrum. The calculated results indicate that the pre-equilibrium mechanism dominates the whole reaction processes, and the recoil effect in light nuclear reactions is essentially important.

关键词： total outgoing neutron energy-angular spectrum light nucleus reaction

Theoretical Analysis of Neutron Double-Differential Cross Section of n ＋^19F at 14.2 MeV

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Communications in Theoretical Physics 2007年第1期47卷 102-106页

作者： YAN Yu-Liang sun xiao-jun ZHANG Yue ZHANG Jing-Shang China Institute of Atomic Energy P.O. Box 275（41） Beijing 102413 China College of Physics and Information Technology Guangxi Normal University Guilin 541004 China

A new light nuclear reaction model has been developed and the double-differential measurements of lp shell nuclei have been analyzed successfully. Now, the application of this model is expanded to 19F of the 2s-ld shell nucleus. The double-differential cross section of total outgoing neutron for n ＋^19F reactions at En=14.2 MeV has been calculated and analyzed, which agrees fairly well with the experimental measurements. In this paper, the contributions from different reaction channels to the double-differential cross sections have been analyzed in detail. The calculations indicate that this light nudear reaction model is also able to be used for the 2s-ld shell nucleus so long as the related level scheme couM be provided sufficiently.

关键词： light nuclear reaction double-differential cross section pre-equillbrium emission discrete level

Postoperative pituitary hormonal disturbances and hormone replacement therapy time and dosage in children with craniopharyngiomas

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Chinese Medical Journal 2008年第20期121卷 2077-2082页

作者： LI Gui-mei sun xiao-jun SHAO Peng Department of Pediatrics Provincial Hospital Affiliated to Shandong University Jinan Shandong 250021 China

Background The proliferative activity and penetration into the hypothalamic structures in children craniopharyngiomas （CP） often make radical resection difficult. Therefore, complete resection of CP often results in permanent multiple pituitary hormone deficiency （MPHD）. This study aimed to elucidate the postoperative pituitary hormonal disturbances, and hormone replacement therapy （HRT） time and dosage in children with CP. Methods Twenty patients with growth retardation and CP after resection, comprising 14 boys and 6 girls, with a mean age of （10.63±3.18） years （Group A） and 10 male patients of group A aged 〉10 years （Group B） were entolled. Thirty age-, sex- and Tanner stage-matched normal children （control Group A）, and 44 male older children 〉10 years （control Group B） served as controls. The serum concentrations of insulin-like growth factor-1 （IGF-1）, growth hormone （GH）, free thyroxine （FT4）, thyroid-stimulating hormone （TSH）, adrenocorticortropic hormone （ACTH）, cortisol （COR）, follicle stimulating hormone （FSH）, luteinizing hormone （LH）, prolactin （PRL）, testosterone （T） and estradiol （E2） were measured in the CP patients after resection and in controls. The appropriate time and dosage of HRT were investigated. Linear correlation analysis was made between levothyroxine （L-T4） dosage and primary FT4 in CP patients after resection. Results All cases had MPHD. The serum peak GH, IGF-1, FT4 and COR levels of Group A were significantly lower than that of the control Group A. The serum IGF-1 concentration increased to the normal level after 3 months of rhGH therapy; the serum FSH, LH, and T levels were significantly decreased （P 〈0.001）; however, E2 and PRL were significantly increased （P 〈0.001） in Group B compared with the control Group B; 18 cases were found to have central diabetes insipidus （DI） by water deprivation test and MRI. There was a significant negative linear regression （r=-0.8, P 〈0.001） between L-T4 and primary FT4 in Group A patients with C

关键词： craniopharyngiomas postoperative children multiple pituitary hormone deficiency hormone replacement therapy

Prospective study of scoring system in selective intraoperative cholangiography during laparoscopic cholecystectomy

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World Journal of Gastroenterology 2003年第4期9卷 865-867页

作者： xiao-Dong sun xiao-Yan Cai jun-Da Li Xiu-jun Cai Yi-Ping Mu Jin-Min Wu Department of General Surgery,The Affiliated Sir Run Run Shaw Hospital,Zhejiang University Medical College,Hangzhou 310016,Zhejiang Province,China Department of General Surgery The Affiliated Sir Run Run Shaw Hospital Zhejiang University Medical College Hangzhou 310016 Zhejiang Province China. s.xiaodong@***

AIM: To evaluate of scoring system in predicting choledocholithiasis in selective intraoperative cholangiography (IOC) during laparoscopic cholecystectomy (LC).METHODS: The scoring system of predicting choledocholithiasis was developed during the retrospective study in 264 cases, and was tested in 184 to evaluate its predictive value in ***: The scoring system was developed in a retrospective study of 264 cases, the statistical analyses showed the predictive factors included sex, transaminase levels, alkaline phosphatase level, bilirubin level, and common bile duct diameter on ultrasonography. The scoring system was used in 184 cases prospectively, of which, 3 of 162 (1.9%) cases scoring ＜3 had choledocholithiasis, 17 of 22 (77.3 %) cases scores≥3 had choledocholithiasis. A case of scores≥3 or more prospectively should be considered highly intraoperative cholangiography during laparoscopic ***: The scoring system can predict choledocholithiasis and is helpful in selection patietns for intraoperative cholangiography.

关键词：术中选择性胆管造影术腹腔镜胆囊切除术胆道疾病计分系统临床研究

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求解带时间窗车辆路径问题的混合智能算法

大连理工大学学报 2015年第2期55卷 209-214页

作者：孙小军宝鸡文理学院数学与信息科学学院陕西宝鸡721013

基于布谷鸟搜索算法和单亲遗传算法,设计了一种求解带时间窗车辆路径问题的混合智能算法.该算法首先对客户位置进行聚类分析,然后再进行各区域的路径优化.混合智能算法不仅改进了布谷鸟搜索算法中当鸟卵被鸟窝主人发现后需要随机改变整... 详细信息

基于布谷鸟搜索算法和单亲遗传算法,设计了一种求解带时间窗车辆路径问题的混合智能算法.该算法首先对客户位置进行聚类分析,然后再进行各区域的路径优化.混合智能算法不仅改进了布谷鸟搜索算法中当鸟卵被鸟窝主人发现后需要随机改变整个鸟窝位置的操作,同时引入的单亲遗传算法加快了最优配送路线的搜索速度.分析和比较了混合智能算法与布谷鸟搜索算法的计算复杂度.最后采用国际通用标准测试集Benchmark Problems进行测试.结果显示,混合智能算法是求解带时间窗车辆路径问题的一种有效算法.

关键词：车辆路径问题时间窗布谷鸟搜索算法单亲遗传算法

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级联码中的高码率短码长SLT码设计

系统工程与电子技术 2013年第3期35卷 634-637页

作者：刘晓健孙小钧上海航天局第八二研究所上海200090 东南大学移动通信国家重点实验室江苏南京210096

将SLT(system Luby transform)码,尤其是高码率短码长的SLT码与低密度校验(low density pari-ty check,LDPC)码等信道纠错码级联,可以通过增加少量的译码开销来有效地提高译码增益。然而,基于传统的设计方法得到的编码包度数分布难以保... 详细信息

将SLT(system Luby transform)码,尤其是高码率短码长的SLT码与低密度校验(low density pari-ty check,LDPC)码等信道纠错码级联,可以通过增加少量的译码开销来有效地提高译码增益。然而,基于传统的设计方法得到的编码包度数分布难以保证在这种情况下得到性能良好的码字。结合级联译码的场景,在传统的优化方法基础上,增加了对编码包度数分布的优化,同时改进了具体的构造方法,从而给出了一种高码率短码长的SLT码的设计方法。仿真结果显示,新方法设计的码字能够取得良好的性能。

关键词：系统喷泉码 SLT码置信度传播译码