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中国科学院上海有机化学研究所游书力研究团队在研究铱催化的不对称烯丙基取代反应时，首次发现了一种独特的“时间调控手性反转”现象：使用一个构型的手性催化剂，仅通过调节反应时长可以高对映选择性地获得产物的一对对映异构体，该成果于2020年6月29日在国际期刊Nature Chemistry在线发表。近日，该成果被美国《化学与化工新闻》（Chemical & Engineering News）评选为202...
系统评价机器人和腹腔镜 Roux-en-Y 胃旁路术（RYGB）治疗病态肥胖的安全性和有效性。方法 计算机检索 PubMed、Embase、Cochrane Library、万方数据、CBM、CNKI 等数据库，收集机器人和腹腔镜 RYGB 治疗病态肥胖的相关研究。由 2 名研究者独立进行文献筛选和数据提取，采用 R 软件进行统计学分析。
2019年8月25日，美国化学会(ACS)旗下全球化学化工领域最有影响力的新闻杂志《化学与工程新闻》（Chemical & Engineering News,C&EN）公布了2019年入选Talented 12的青年科学家名单，北京大学化学与分子工程学院邹鹏研究员本年度入选该名单，这是此次12名入选者中唯一在亚洲地区从事科学研究工作的学者。邹鹏2007年本科毕业于北京大学化学学院，获化学和物理学双...
Actitudes y experiencia sexual en mujeres jóvenes Attitudes and sexual experience in young women
mujeres jóvenes Attitudes sexual experience
2015/7/30
The Hudson et al Test (1983) has demonstrated an adequate interna1 consistency (Alpha = 0.81)
as well as its validity for measuring sexual attitudes. This is due to the possibility of finding - by
m...
Femmes et migration en Côte d’Ivoire : le mythe de l’autonomie
de l’autonomie Cô te d’Ivoire
2015/7/21
En Côte d’ivoire, comme dans d’autres pays africains les migrations traditionnellement dominéespar les hommes se féminisent progressivement. Les résultats de l’Enquête Ivoirienne sur les Migratio...
PERSUASION Y PRESCRIPCION EN EL DISCURSO DEL CAMBIO CLIMATICO
PERSUASION PRESCRIPCION DEL CAMBIO CLIMATICO
2015/7/10
In the last decades, climate change and global warming appear as a paradigm example of problems in “risk societies”, where risks are invisible and can be known through interpretations made by scientis...
2015年4月9日至10日，美国化学会Chemical & Engineering News (C&EN)主编A. Maureen Rouhi博士和ACS北京办事处代表马清扬女士一行两人来中国科学院大连化学物理研究所交流访问，中国科学院大连化学物理研究所科技处和研究组相关人员参加了活动。
Sistemas de Lie y sus aplicaciones en Fisica y Teoria de Control
Lie systems Control Theory Mathematical Physics
2011/7/26
Sistemas de Lie y sus aplicaciones en Física y Teoría de Control.
Numerical Simulations of Kinetic Alf ´v en Waves to Study Spectral Index in Solar Wind Turbulence and Particle Heating
Kinetic Alfv´ en wave filamentation solar wind spectral index chaotic structure
2010/9/16
We present numerical simulations of the modified nonlinear Schr¨odinger equation satisfied by kinetic Alfv´en waves (KAWs) leading to the formation of magnetic filaments at different times. The ...
Berry-Esséen Bounds for Long Memory Moving Averages via Stein's Method and Malliavin Calculus
limit theorems long memory moving average multiple stochastic integrals Malliavin calculus weak convergence
2010/12/1
Using the Stein method on Wiener chaos introduced in [10] we prove Berry-Ess´een bounds for long memory moving averages.
Rentes en cours de service : un nouveau critère d'allocation d'actif
Defined benefit plan asset allocation ruin probability economics capital mutualization pension adjustment
2010/4/27
The aim of this paper is to compare two asset allocation methods for a pension scheme during the decumulation phase in the simplified portfolio selection between a risky asset following a geometric Br...
Mesure des risques de marché et de souscription vie en situation d'information incomplète pour un portefeuille de prévoyance
Embedded Value Cost of Residual Non Hedgeable risks (CRNHR) Time Value of Financial Options and Guarantees (TVFOG) individual protection
2010/4/27
In the framework of Embedded Value new standards, namely the MCEV norms, the latest principles published in June 2008 address the issue of market and underwriting risks measurement by using stochastic...
L'utilisation des splines bidimensionnels pour l'estimation de lois de maintien en arrêt de travail
Disability Kaplan-Meier splines estimation
2010/4/27
The aim of this paper is to propose an operational two-dimensional parametric adjustment for laws of maintenance in disability. The method suggested rests on splines in dimension 2; it is applied to a...
Allocation d'actifs selon le critère de maximisation des fonds propres économiques en assurance non-vie
maximization criterion non-life insurance company expected value
2010/4/27
The economic equities maximization criterion (MFPE) leads to the choice of financial portfolio, which maximizes the ratio of the expected value of the insurance company on the capital. This criterion ...
REMOCIóN DE SEMILLAS, HERBIVORíA Y RECLUTAMIENTO DE PLáNTULAS DE BROSIMUM ALICASTRUM (MORACEAE) EN SITIOS CON MANEJO FORESTAL CONTRASTANTE DE LA SELVA MAYA, QUINTANA ROO, MéXICO
Brosimum alicastrum regeneration surviving
2015/11/13
The impact of timber extraction was evaluated on Brosimum alicastrum, particularly on seed removal, recruitment and
seedling herbivory. A series of experimental exclusions were established in logged...