氨基酸手性同一起源的新理论模型

氨基酸手性同一,这一生命体系特有的行为,可能伴随着密码子的起源而形成.在此假设的前提下,本文将带有P-N键的核苷-5′-磷酰化氨基酸化合物作为前生物时期的手性起源模型来探讨手性的选择.在这个模型化合物中,由于氨基酸手性原子的存在,导致氨基酸侧链和核苷酸碱基之间出现最佳空间取向差异,进而影响到分子内部不同官能基团之间的相互作用,氨基酸的某种手性可能成为优势构型,有利于该化合物的稳定.为了验证这一氨基酸手性同一起源模型,本文从实验和理论上做了初步研究.研究结果显示,古老氨基酸的L型异构体优先被选择遵从立体/物理化学决定论,而随后出现的氨基酸,其手性的选择可能是手性继承的结果.以上工作是氨基酸手性同一起源的一种猜测,为进一步开展实验验证提供依据和思路.国家自然科学基金(批准号:20572061);; 厦门大学人才引进基金(批准号:Z03120)资助项

Simultaneous determination of 87 pesticides in river water and seawater using solid phase extraction-gas chromatography-mass spectrometry

采用固相萃取-气相色谱-质谱联用技术,建立了河水和海水中87种农药(24种有机磷、15种有机氯、12种唑类、9种拟除虫菊酯类、5种氨基甲酸酯类、7种酰胺类及15种其他新型农药)的多残留同时分析方法。优化了影响分离效果和灵敏度的仪器参数,考察了固相萃取柱柱型及水样体积、PH、盐度的影响,采用nH2柱优化了净化效果,内标法和替代物法用于数据的质量控制。结果表明:在最佳条件下,各目标农药的方法检出限为0.1~6.6ng/l;以实际河水和海水为基底,在5 ng/l和20 ng/l的加标水平下,绝大多数目标农药的回收率为60%~120%,相对标准偏差(n=4)为0.01%~9.7%。该法灵敏、准确,已成功地应用于福建九龙江河口区表层水样中多种类农药的复合污染监测,检出包括5种有机磷类、3种酰胺类、4种唑类、3种氨基甲酸酯类、2种拟除虫菊酯类等农药20种。A method for the simultaneous determination of 87 commonly used pesticides in China including 24 organophosphorous pesticides,15 organochlorine pesticides,12 azoles,9 pyrethroids,7 amides and anilines,5 carbamates and other 15 pesticides in river water and seawater was established using solid phase extraction(SPE)-gas chromatography-mass spectrometry(GC-MS).GC-MS parameters influencing separation and sensitivity were optimized,and the effects of sample volume,pH and salinity on SPE were investigated.The purification was performed using NH2 SPE cartridge.An internal standard and 5 surrogates were used for data analysis and quality control.The results indicated that under the optimized conditions the limits of detection were in the range of 0.1-6.6 ng / L.For most target pesticides,recoveries were between 60% and 120% with relative standard deviations(RSDs,n = 4) of 0.01%-9.7% at the spiked levels of 5 ng / L and 20 ng / L in real river water and sea water matrices.The method was successfully applied to monitor multi-class pesticides in surface water in Fujian Jiulong estuary,and 20 pesticides including 5 organophosphorous pesticides,3 amides,4 azoles,3 carbamates,2 pyrethroids and 3 other pesticides were detected in the mass concentration range of 1.18-660.93 ng / L.The proposed method can meet the requirement for the determination of trace pesticide residues in water samples.厦门市重大科技平台项目(3502Z20091005

Parametric design and optimization of high speed train nose

Aiming at shortening the design period and improve the design efficiency of the nose shape of high speed trains, a parametric shape optimization method is developed for the design of the nose shape has been proposed in the present paper based on the VMF parametric approach, NURBS curves and discrete control point method. 33 design variables have been utilized to control the nose shape, and totally different shapes could be obtained by varying the values of design variables. Based on the above parametric method, multi-objective particle swarm algorithm, CFD numerical simulation and supported vector machine regression model, multi-objective aerodynamic shape optimization has been performed. Results reveal that the parametric shape design method proposed here could precisely describe the three-dimensional nose shape of high speed trains and could be applied to the concept design and optimization of the nose shape. Besides, the SVM regression model based the multi-points criterion could accurately describe the non-linear relationship between the design variables and objectives, and could be generally utilized in other fields. No matter the simplified model or the real model, the aerodynamic performance of the model after optimization has been greatly improved. Based on the SVR model, the nonlinear relation between the aerodynamic drag and the design variables is obtained, which could provide guidance for the engineering design and optimization

Parametric design and optimization of high speed train nose

Aiming at shortening the design period and improve the design efficiency of the nose shape of high speed trains, a parametric shape optimization method is developed for the design of the nose shape has been proposed in the present paper based on the VMF parametric approach, NURBS curves and discrete control point method. 33 design variables have been utilized to control the nose shape, and totally different shapes could be obtained by varying the values of design variables. Based on the above parametric method, multi-objective particle swarm algorithm, CFD numerical simulation and supported vector machine regression model, multi-objective aerodynamic shape optimization has been performed. Results reveal that the parametric shape design method proposed here could precisely describe the three-dimensional nose shape of high speed trains and could be applied to the concept design and optimization of the nose shape. Besides, the SVM regression model based the multi-points criterion could accurately describe the non-linear relationship between the design variables and objectives, and could be generally utilized in other fields. No matter the simplified model or the real model, the aerodynamic performance of the model after optimization has been greatly improved. Based on the SVR model, the nonlinear relation between the aerodynamic drag and the design variables is obtained, which could provide guidance for the engineering design and optimization

新型稠环电子受体的界面修饰对钙钛矿太阳能电池性能的影响

钙钛矿太阳能电池(perovskite solar cells, PSCs)因具有能量转换效率(power conversion efficiency, PCE)高、成本低、易于大面积制造等优点而被科学家们广泛关注.氧化物电子传输层的合理界面设计及修饰对提高器件的PCE和工作长期稳定性有着十分重要的意义.因此,本文采用一种含有烷基噻吩基侧链的稠环电子受体材料3,9-二(2-亚甲基-(3-(1,1-二氰甲烯基)-茚酮))-5,5,11,11-四(5-己基噻吩)-二噻吩并[2,3-d:2′,3′-d′]-s-引达省[1,2-b:5,6-b′]二噻吩(3,9-bis(2-methylene-(3-(1,1-dicyanomethylene)-indanone))-5,5,11,11-tetrakis(5-hexylthienyl)-dithieno[2,3-d:2′,3′-d′]-s-indaceno[1,2-b:5,6-b′]dithiophene, ITIC-Th)修饰TiO2电子传输层,制备高效稳定的平面结PSCs.研究结果显示,ITIC-Th的界面修饰改善了TiO2薄膜的形貌、接触角等性质,促进了钙钛矿晶粒的高质量生长,大幅度减少了器件表界面的电荷复合,明显提升了光生载流子的抽取率和输运效率,使经ITIC-Th界面修饰的PSC的PCE从未经界面修饰的15.43%显著提高到18.91%.与此同时,器件稳定性的研究结果显示,在室温和湿度为30%的条件下,经ITICTh界面修饰的PSC的PCE在放置约1000 h后依然保持原来的90%,明显高于未经界面修饰的PSC.研究结果对PSC光伏性能的提升具有重要的实际应用价值和学术意义.国家自然科学基金(61605164);;\n陕西省重点科技创新团队计划(2016KCT-28);;\n陕西省重点研发计划(2017ZDXM-GY-046);;\n福建省科技厅高校产学合作项目(2016H6023)资

加快“双一流”建设 实现高等教育内涵式发展(笔谈)

为学习宣传习近平总书记关于教育的重要论述、贯彻落实全国教育大会精神、奋力谱写高等教育事业的新篇章,2018年11月3—4日,由中国高等教育学会主办的\"2018高等教育国际论坛年会\"在浙江宁波隆重举行。本届论坛主题为\"加快‘双一流’建设,实现内涵式发展\"。高等教育内涵式发展是新时期我国高等教育发展的新特征,同时也是新时代对高等教育改革创新提出的新要求。\"双一流\"建设是新时期高等教育改革的适时之举,是实现高等教育内涵式发展的标杆战略,旨在统筹高等教育结构、规模、质量、效益协调发展。\"双一流\"建设需要加强和改进党对高校的领导,完善高校内部治理结构与评价体系,加快推进人才培养模式改革,丰富高等教育教学模式、方式与方法,促进高校学科发展良性化,拓展高等教育国际化发展新渠道,等等。与会领导、专家学者从不同方面探讨、分享了\"双一流\"建设的理念与经验,剖析了高等教育内涵式发展的特征及实现路径,勾画了\"双一流\"建设的未来图景。本刊选发部分发言人的观点摘编,供读者参阅

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目的 研究高危型人乳头瘤病毒（HR-HPV）感染相关的宫颈病变程度与抗人乳头瘤状病毒（HPV）抗体水平的相关性,探讨HPV致病的免疫学问题。方法 选取2012年1月-2013年6月在该院妇产科门诊就诊的女性中选取60例病理确诊为女性宫颈病变（CINⅠ及以上）,且宫颈脱落细胞的DNA检测为HR-HPV阳性者为研究组,根据组织学检测结果将研究组进一步分为低度病变组30例（CINⅠ）和高度病变组30例（CINⅡ或Ⅲ）。对照组为经核酸检测无HPV感染且病理诊断未见癌前病变的门诊患者60例,按年龄进一步分为低年龄组和高年龄组。低年龄组和高年龄组与低度病变组和高度病变组的年龄差异无统计学意义（P〉0.05）。分别抽取研究组及对照组外周血,检测其抗HR-HPV L1 Ig G抗体及中和抗体滴度,比较研究组与对照组抗体阳性率及抗体滴度水平的差别。结果 研究组血清中的抗HR-HPV L1 Ig G抗体阳性率及抗体滴度均高于对照组（P〈0.05）;低度病变组患者血清中的抗HR-HPV的中和抗体滴度高于相应对照组（P〈0.05）,而高度病变组的抗HR-HPV的中和抗体阳性率及抗体水平与相应对照组比较差异无统计学意义（P〉0.05）。结论 宫颈病变患者血清中抗HR-HPV L1 Ig G抗体升高,说明HPV感染可引起机体的体液免疫反应。低度病变组的中和抗体水平相对较高,可能是机体产生的中和抗体阻止了病毒的进一步感染。高度病变组的Ig G抗体和中和抗体均低下,说明进入CINⅡ/Ⅲ后HPV已经逃避了免疫系统的监视。基金项目：厦门市科技局项目（3502220124050）;2011年福建省科技计划项目资助计划,青年创新项目（20111）00310517

Y型聚乙二醇干扰素琢-2b注射液治疗HCV基因2/3型慢性丙型肝炎患者疗效和安全性的多中心随机对照试验研究

目的以标准剂量的聚乙二醇干扰素(Peg IFN)α-2a联合利巴韦林作为阳性对照,评价新型试验药物Y型Peg IFNα-2b注射液联合利巴韦林治疗2型/3型慢性丙型肝炎(CHC)患者的疗效和安全性。方法采用多中心、随机开放、阳性药对照的Ⅲ期临床试验,筛选符合要求的2型/3型CHC患者,按照2:1的比例随机分配到Y型Peg IFNα-2b组和Peg IFNα-2a组,同时口服利巴韦林,疗程24 w,停药随访24 w。采用Abbott Real Time HCV Genotype II检测HCV基因型,采用Cobas Taq Man实时定量PCR法检测血清HCV RNA水平。详细记录不良事件。主要疗效指标为持续病毒学应答(SVR),并进行非劣效检验。结果本试验实际入组2型/3型CHC患者255例,实际治疗241例。全分析集(FAS)数据显示,158例试验组和83例对照组患者SVR分别为85.4%(95%CI 79.94%~90.94%)和79.5%(95%CI 70.84%~88.20%,P=0.2402);对符合方案分析集(PPS)人群分析显示,试验组和对照组患者SVR分别为87.9%(95%CI 82.45%~93.27%)和85.9%(95%CI 77.82%~94.01%,P=0.7060),率差的95%可置信区间均符合非劣效标准;对PPS人群分析显示,85.8%受试者获得了早期病毒学应答(RVR),RVR的阳性预测值为90.1%;试验组和对照组不良事件发生率相似,分别为95.6%和95.2%,严重不良事件发生率分别为3.8%和3.6%。结论应用Peg IFNα联合利巴韦林治疗2型/3型CHC患者,新型试验药物Y型Peg IFNα-2b具有与对照药物Peg IFNα-2a相似的疗效和安全性。国家科技部“十二五”重大专项(编号:2012ZX10002-003)；“重大新药创制”十二五科技重大专项(编号:2012ZX09303019)

纪念五四宪法颁布暨全国人民代表大会成立五十周年理论研讨会纪要

今年 9月是五四宪法颁布、全国人民代表大会成立五十周年。五四宪法是新中国的第一部宪法 ,为我国的社会主义民主法制奠定了基础 ,具有划时代的意义。坚持和完善人民代表大会制度 ,是新的历史条件下推进政治体制改革和社会主义政治文明建设的重要内容。基于“以学术表达纪念、以纪念促进学术”的目的 ,中国社会科学院法学研究所于 2 0 0 4年 9月 5日举办了“纪念五四宪法颁布暨全国人民代表大会成立五十周年理论研讨会”。来自全国各地的 70余位代表莅临会议 ,研讨了诸多热点和前沿问题