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Monomer-activated Copolymerization of Ethylene Oxide and Epichlorohydrin: In Situ Kinetics Evidences Tapered Block Copolymer Formation
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作者 Ann-Kathrin Danner Daniel Leibig +1 位作者 Lea-Marie Vogt Holger Frey 《高分子科学:英文版》 SCIE CAS CSCD 2019年第9期912-918,共7页
The monomer-activated anionic ring-opening copolymerization (AROP) of ethylene oxide (EO) and epichlorohydrin (ECH) using tetraoctylammonium bromide as an initiator and triisobutylaluminum (i-Bu3Al) as an activator wa... The monomer-activated anionic ring-opening copolymerization (AROP) of ethylene oxide (EO) and epichlorohydrin (ECH) using tetraoctylammonium bromide as an initiator and triisobutylaluminum (i-Bu3Al) as an activator was studied. The properties of the copolymers as well as the microstructure have been analyzed in detail via an in situ NMR kinetics study. The statistical copolymers exhibited molecular weights ranging from 2350 g·mol^-1 to 38000 g·mol^-1 (measured by SEC, PEG-standards) and moderate dispersities of 1.27-1.44. The thermal property tests revealed both a glass transition and melting for all copolymers, supporting a block-like nature. Applying in situ NMR kinetic measurements, the reactivity ratios of EO and ECH were determined to be strongly disparate, i.e., rEo = 9.2 and rECH = 0.10. This shows that the simple one-pot statistical anionic copolymerization of EO and ECH via the monomer-activated AROP resulted in the formation of strongly tapered, block-like structures. Furthermore, post-polymerization functionalization of the reactive chloromethyl groups by nucleophilic displacement was investigated for the copolymers. Copolymerization of EO and ECH offers a broad platform for further functionalization and therefore the possibility to prepare a variety of multifunctional PEGs. 展开更多
关键词 EPICHLOROHYDRIN Polymerization RING-OPENING COPOLYMERIZATION Reactivity ratios EPOXIDE
Observation of e+e?→D+sDˉˉˉˉ(?)0K?e+e?→Ds+Dˉ(?)0K?and study of the P-wave DsDs mesons
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作者 麦迪娜 M.N.Achasov +143 位作者 S.Ahmed M.Albrecht M.Alekseev A.Amoroso 安芬芬 安琪 白羽 O.Bakina R.Baldini Ferroli 班勇 K.Begzsuren D.W.Bennett J.V.Bennett N.Berger M.Bertani D.Bettoni F.Bianchi I.Boyko R.A.Briere 蔡浩 蔡啸 A.Calcaterra 曹国富 S.A.Cetin J.Chai 常劲帆 W.L.Chang G.Chelkov 陈刚 陈和生 陈江川 陈玛丽 陈申见 陈元柏 成伟帅 G.Cibinetto F.Cossio 代洪亮 代建平 A.Dbeyssi D.Dedovich 邓子艳 A.Denig I.Denysenko M.Destefanis F.De Mori 丁勇 董超 董静 董燎原 董明义 豆正磊 杜书先 范荆州 方建 房双世 方易 R.Farinelli L.Fava F.Feldbauer G.Felici 封常青 M.Fritsch 傅成栋 付颖 高清 高鑫磊 高原宁 高勇贵 高榛 B.Garillon I.Garzia A.Gilman K.Goetzen 龚丽 龚文煊 W.Gradl M.Greco 谷立民 顾旻皓 顾珊 顾运厅 郭爱强 郭立波 郭如盼 郭玉萍 A.Guskov Z.Haddadi 韩爽 郝喜庆 F.A.Harris 何康林 F.H.Heinsius T.Held 衡月昆 侯治龙 胡海明 胡继峰 胡涛 胡誉 黄光顺 黄金书 黄性涛 黄晓忠 黄智玲 N.Huesken T.Hussain W.Ikegami Andersson W.Imoehl M.Irshad 纪全 姬清平 季晓斌 季筱璐 姜侯兵 江晓山 蒋兴雨 焦健斌 焦铮 金大鹏 金山 金毅 T.Johansson N.Kalantar-Nayestanaki 康晓珅 M.Kavatsyuk 柯百谦 I.K.Keshk T.Khan A.Khoukaz P.Kiese R.Kiuchi R.Kliemt L.Koch O.B.Kolcu B.Kopf M.Kuemmel M.Kuessner A.Kupsc M.Kurth W.Kühn J.S.Lange P.Larin L. 《中国物理C:英文版》 SCIE CAS CSCD 2019年第3期5-16,共12页
Studies of e+e?→D+sDˉˉˉˉ(?)0K?e+e?→Ds+Dˉ(?)0K?and the PP-wave charmed-strange mesons are performed based on an e+e?e+e?collision data sample corresponding to an integrated luminosity of 567 pb?1 collected with ... Studies of e+e?→D+sDˉˉˉˉ(?)0K?e+e?→Ds+Dˉ(?)0K?and the PP-wave charmed-strange mesons are performed based on an e+e?e+e?collision data sample corresponding to an integrated luminosity of 567 pb?1 collected with the BESIII detector at s√=4.600s=4.600 GeV.The processes of e+e?→D+sDˉˉˉˉ?0K?e+e?→Ds+Dˉ?0K?and D+sDˉˉˉˉ0K?Ds+Dˉ0K?are observed for the first time and are found to be dominated by the modes D+sDs1(2536)?Ds+Ds1(2536)?and D+sD?s2(2573)?Ds+Ds2?(2573)?,respectively.The Born cross sections are measured to beσB(e+e?→D+sDˉˉˉˉ?0K?)=(10.1±2.3±0.8)σB(e+e?→Ds+Dˉ?0K?)=(10.1±2.3±0.8)pb andσB(e+e?→D+sDˉˉˉˉ0K?)=(19.4±2.3±1.6)σB(e+e?→Ds+Dˉ0K?)=(19.4±2.3±1.6)pb,and the products of Born cross section and the decay branching fraction are measured to beσB(e+e?→D+sDs1(2536)?+c.c.)?σB(e+e?→Ds+Ds1(2536)?+c.c.)?B(Ds1(2536)?→Dˉˉˉˉ?0K?)=(7.5±1.8±0.7)B(Ds1(2536)?→Dˉ?0K?)=(7.5±1.8±0.7)pb andσB(e+e?→D+sD?s2(2573)?+c.c.)?B(D?s2(2573)?→Dˉˉˉˉ0K?)=σB(e+e?→Ds+Ds2?(2573)?+c.c.)?B(Ds2?(2573)?→Dˉ0K?)=(19.7±2.9±2.0)(19.7±2.9±2.0)pb.For the Ds1(2536)?Ds1(2536)?and D?s2(2573)?Ds2?(2573)?mesons,the masses and widths are measured to be M(Ds1(2536)?)=(2537.7±0.5±3.1)MeV/c2M(Ds1(2536)?)=(2537.7±0.5±3.1)MeV/c2,Γ(Ds1(2536)?)=(1.7±1.2±0.6)Γ(Ds1(2536)?)=(1.7±1.2±0.6)MeV,and M(D?s2(2573)?)=M(Ds2?(2573)?)=(2570.7±2.0±1.7)MeV/c2,(2570.7±2.0±1.7)MeV/c2,Γ(D?s2(2573)?)=(17.2±3.6±1.1)Γ(Ds2?(2573)?)=(17.2±3.6±1.1)MeV.The spin-parity of the D?s2(2573)?Ds2?(2573)?meson is determined to be JP=2+JP=2+.In addition,the processes e+e?→D+sDˉˉˉˉ(?)0K?e+e?→Ds+Dˉ(?)0K?are searched for using the data samples taken at four(two)center-of-mass energies between 4.416(4.527)and 4.575 GeV,and upper limits at the 90%confidence level on the cross sections are determined. 展开更多
关键词 cross section P-WAVE D_s MESONS resonance parameters spin-parity BESIII
Evidence for the decays of ∧c^+→∑^+η and ∑^+η’
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作者 麦迪娜 M.N.Achasov +146 位作者 S.Ahmed M.Albrecht M.Aleksee A.Amoroso 安芬芬 安琪 白羽 O.Bakina R. Baldini Ferroli 班勇 K.Begzsuren D.W.Bennett J.V.Bennett N.Berger M.Bertani D.Bettoni F.Bianchi I.Boyko R.A.Briere 蔡浩 蔡啸 O.Cakir A.Calcaterra 曹国富 S.A.Cetin J.Chai 常劲帆 W.L.Chang G.Chelkov 陈刚 陈和生 陈江川 陈玛丽 陈平亮 陈申见 陈元柏 成伟帅 G.Cibinetto F.Cossio 代洪亮 代建平 A.Dbeyssi D.Dedovich 邓子艳 A.Denig I.Denysenko M.Destefanis F.De Mori 丁勇 董超 董静 董燎原 董明义 豆正磊 杜书先 段鹏飞 范荆州 方建 房双世 方易 R.Farinelli L.Fava S.Fegan F.Feldbauer G.Felici 封常青 M.Fritsch 傅成栋 付颖 高清 高鑫磊 高原宁 高勇贵 高榛 B.Garillon I.Garzia A.Gilman K.Goetzen 龚丽 龚文煊 W.Gradl M.Greco 谷立民 顾旻皓 顾运厅 郭爱强 郭立波 郭如盼 郭玉萍 A.Guskov Z.Haddadi 韩爽 郝喜庆 F.A.Harris 何康林 F.H.Heinsius T.Held 衡月昆 侯治龙 胡海明 胡继峰 胡涛 胡誉 黄光顺 黄金书 黄性涛 黄晓忠 黄智玲 T.Hussain N.Hu sken W.Ikegami Andersson M.Irshad 纪全 姬清平 季晓斌 季筱璐 江晓山 蒋兴雨 焦健斌 焦铮 金大鹏 金山 金毅 T.Johansson A.Julin N.Kalantar-Nayestanaki 康晓珅 M.Kavatsyuk 柯百谦 I.K.Keshk T.Khan A.Khoukaz P.Kiese R.Kiuchi R.Kliemt L.Koch O.B.Kolcu B.Kopf M.Kornicer M.Kuemmel M.Kuessner A.Kupsc M.Kurth W.Kuhn J.S.Lange P.Larin L.La 《中国物理C:英文版》 SCIE CAS CSCD 2019年第8期15-23,共9页
We study the hadronic decays of ∧c^+ to the final states ∑^+η and ∑^+η, using an e^+e^- annihilation data sample of 567 pb^-1 taken at a center-of-mass energy of 4.6 GeV with the BESIII detector at the BEPCII col... We study the hadronic decays of ∧c^+ to the final states ∑^+η and ∑^+η, using an e^+e^- annihilation data sample of 567 pb^-1 taken at a center-of-mass energy of 4.6 GeV with the BESIII detector at the BEPCII collider. We find evidence for the decays ∧^+→∑^+η and ∑^+η' and with statistical significance of and , respectively. Normalizing to the reference decays ∧^+→∑^+π^0 and ∑^+ω, we obtain the ratios of the branching fractions B(∧C^+→∑^+η)/V(∧^→∑^+π^0)and B(∧C^+→∑^+η)/B(∧C^+→∑^+ω)to be and , respectively. The upper limits at the 90% confidence level are set to be B(∧C^→∑^+η)/V(∧^+→∑^+π^0)<0.58 and B(∧C^+→∑^+η)/B(∧C^+→∑^+ω)<1.2. Using BESIII measurements of the branching fractions of the reference decays, we determine B(∧C^+→∑^+η)=(0.41±019±0.05)%(<0.68%) and B(∧C^+→∑^+η)=(1.34+0.53+0.19)%(<1.9%). Here, the first uncertainties are statistical and the second systematic. The obtained branching fraction of ∧C^+→∑^+η is consistent with the previous measurement, and the branching fraction of ∧C^+→∑^+η is measured for the first time. 展开更多
关键词 charmed BARYON ∧c^+ DECAYS branching FRACTIONS
效应量置信区间的原理及其实现 预览
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作者 王珺 宋琼雅 +2 位作者 许岳培 贾彬彬 胡传鹏 《心理技术与应用》 2019年第5期284-296,共13页
在心理学可重复危机的背景之下,报告效应量及其置信区间正逐渐成为主流心理学界所要求的新标准,但是研究者可能对效应量的置信区间缺乏足够的理解。为增强研究者对效应量置信区间的理解及应用,本文介绍了心理学研究中最常用的效应量指... 在心理学可重复危机的背景之下,报告效应量及其置信区间正逐渐成为主流心理学界所要求的新标准,但是研究者可能对效应量的置信区间缺乏足够的理解。为增强研究者对效应量置信区间的理解及应用,本文介绍了心理学研究中最常用的效应量指标——Cohen's d与η^2——置信区间的基本原理,即在备择假设(H1)为真时,需要通过迭代估计的方式来估计相应非中心分布的非中心分布参数,从而构建Cohen's d与η^2的置信区间。其中Cohensd对应的是非中心t分布;而η^2对应的则是非中心F分布。使用现有的计算机程序,能够对Cohen's d与η^2的置信区间进行计算,例如R与JASP,本文对此进行了分别展示。报告效应量置信区间不仅有助于研究者更好地进行统计推断,也有利于整个科学界知识的积累,因此本文介绍的方法对研究者具有十分重要的意义。 展开更多
关键词 效应量 置信区间 Cohen's d ETA squared R
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Precision Higgs physics at the CEPC
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作者 安芬芬 白羽 +70 位作者 陈春晖 陈新 陈振兴 Joao Guimaraes da Costa 崔振崴 方亚泉 付成栋 高俊 高艳彦 高原宁 葛韶锋 顾嘉荫 郭方毅 郭军 韩涛 韩爽 何红建 何显柯 何小刚 胡继峰 徐士杰 金山 荆茂强 Susmita Jyotishmati Ryuta Kiuchi 郭家铭 赖培筑 李博扬 李聪乔 李刚 李海峰 李亮 李数 李通 李强 梁浩 梁志均 廖立波 刘波 刘建北 刘涛 刘真 娄辛丑 马连良 Bruce Mellado 莫欣 Mila Pandurovic 钱剑明 钱卓妮 Nikolaos Rompotis 阮曼奇 Alex Schuy 单连友 史静远 史欣 苏淑芳 王大勇 王锦 王连涛 王贻芳 魏彧骞 许悦 杨海军 杨迎 姚为民 于丹 张凯栗 张照茹 赵明锐 赵祥虎 周宁 《中国物理C:英文版》 SCIE CAS CSCD 2019年第4期5-44,共40页
The discovery of the Higgs boson with its mass around 125 GeV by the ATLAS and CMS Collaborations marked the beginning of a new era in high energy physics.The Higgs boson will be the subject of extensive studies of th... The discovery of the Higgs boson with its mass around 125 GeV by the ATLAS and CMS Collaborations marked the beginning of a new era in high energy physics.The Higgs boson will be the subject of extensive studies of the ongoing LHC program.At the same time,lepton collider based Higgs factories have been proposed as a possible next step beyond the LHC,with its main goal to precisely measure the properties of the Higgs boson and probe potential new physics associated with the Higgs boson.The Circular Electron Positron Collider(CEPC)is one of such proposed Higgs factories.The CEPC is an e^+e^- circular collider proposed by and to be hosted in China.Located in a tunnel of approximately 100 km in circumference,it will operate at a center-of-mass energy of 240 GeV as the Higgs factory.In this paper,we present the first estimates on the precision of the Higgs boson property measurements achievable at the CEPC and discuss implications of these measurements. 展开更多
关键词 CEPC HIGGS BOS on HIGGS BOSON properties HIGGS BOSON COUPLINGS HIGGS FACTORY effective field theory EFT
Domestication and crop evolution of wheat andbarley: Genes, genomics, and future directions
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作者 Matthew Haas Mona Schreiber Martin Mascher 《植物学报:英文版》 SCIE CAS CSCD 2019年第3期204-225,共22页
Wheat and barley are two of the founder crops of the agricultural revolution that took place 10,000 years ago in the Fertile Crescent and both crops remain among the world’s most important crops. Domestication of the... Wheat and barley are two of the founder crops of the agricultural revolution that took place 10,000 years ago in the Fertile Crescent and both crops remain among the world’s most important crops. Domestication of these crops from their wild ancestors required the evolution of traits useful to humans, rather than survival in their natural environment. Of these traits, grain retention and threshability, yield improvement, changes to photoperiod sensitivity and nutritional value are most pronounced between wild and domesticated forms. Knowledge about the geographical origins of these crops and the genes responsible for domestication traits largely pre-dates the era of nextgeneration sequencing, although sequencing will lead to new insights. Molecular markers were initially used to calculate distance(relatedness), genetic diversity and to generate genetic maps which were useful in cloning major domestication genes. Both crops are characterized by large,complex genomes which were long thought to be beyond the scope of whole-genome sequencing. However, advances in sequencing technologies have improved the state of genomic resources for both wheat and barley. The availability of reference genomes for wheat and some of its progenitors,as well as for barley, sets the stage for answering unresolved questions in domestication genomics of wheat and barley. 展开更多
关键词 DOMESTICATION WHEAT BARLEY
Pillararene-based fluorescent sensors for the tracking of organic compounds
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作者 Derong Cao Herbert Meier 《中国化学快报:英文版》 SCIE CAS CSCD 2019年第10期1758-1766,共9页
Fluorescent chemosensors based on pillararene complexes represent a new, promising branch in sensor technology. Because of CH-π interactions, aliphatic chains are well suited for the columnar cavities of pillararenes... Fluorescent chemosensors based on pillararene complexes represent a new, promising branch in sensor technology. Because of CH-π interactions, aliphatic chains are well suited for the columnar cavities of pillararenes and bulky or sheet-like(sub)structures can be arranged on the portals. Thus, pillararenes form versatile receptors and an alteration of the fluorescence behavior upon complexation ensures the function of these chemosensors as the reporter. Although this field of research exists only since a few years, remarkable chemosensors were developed for substances as diverse as medical drugs,biochemicals, herbicides and explosives. 展开更多
关键词 Pillararene Fluorescent chemosensor COMPLEX HOST-GUEST Fluorescent cavity
Biotechnology Applications of Plant Callus Cultures 预览
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作者 Thomas Efferth 《工程(英文)》 2019年第1期50-59,共10页
In ethnopharmacology, and especially in traditional Chinese medicine, medicinal plants have been used for thousands of years. Similarly, agricultural plants have been used throughout the history of mankind. The recent... In ethnopharmacology, and especially in traditional Chinese medicine, medicinal plants have been used for thousands of years. Similarly, agricultural plants have been used throughout the history of mankind. The recent development of the genetic engineering of plants to produce plants with desirable features adds a new and growing dimension to humanity’s usage of plants. The biotechnology of plants has come of age and a plethora of bioengineering applications in this context have been delineated during the past few decades. Callus cultures and suspension cell cultures offer a wide range of usages in pharmacology and pharmacy (including Chinese medicine), as well as in agriculture and horticulture. This review provides a timely overview of the advancements that have been made with callus cultures in these scientific fields. Genetically modified callus cultures by gene technological techniques can be used for the synthesis of bioactive secondary metabolites and for the generation of plants with improved resistance against salt, draft, diseases, and pests. Although the full potential of callus plant culture technology has not yet been exploited, the time has come to develop and market more callus culture-based products. 展开更多
关键词 Antibody production EMBRYOGENESIS Gene technology ORGANOGENESIS PHARMACOLOGY PHYTOCHEMISTRY PLANT regeneration Secondary METABOLITES Stem cells
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Pathological tumor response to neoadjuvant therapy in borderline resectable pancreatic cancer 预览
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作者 Stefan Heinrich 《国际肝胆胰疾病杂志:英文版》 SCIE CAS CSCD 2019年第4期305-306,共2页
Surgery is the standard therapy for pancreatic ductal adenocarcinoma(PDAC).After the dramatic decline of operative mortality over the past decades,the indications for pancreas resections have been continuously extende... Surgery is the standard therapy for pancreatic ductal adenocarcinoma(PDAC).After the dramatic decline of operative mortality over the past decades,the indications for pancreas resections have been continuously extended:currently resections of the portal/superior mesenteric vein are considered standard by many centers,and even arterial resections are under debate.Following these changes,different expert groups have defined resectability criteria containing a grey zone(“borderline resectable disease”)of tumors,which may be technically resectable with appropriate surgical expertise,but resection inherits an increased risk of an R1-resection[1]. 展开更多
关键词 SURGERY MORTALITY OPERATIVE
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Percutaneous devices for left atrial appendage occlusion:A contemporary review 预览
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作者 Homam Moussa Pacha Yasser Al-khadra +3 位作者 Mohamad Soud Fahed Darmoch Abdulghani Moussa Pacha M Chadi Alraies 《世界心脏病学杂志:英文版(电子版)》 2019年第2期57-70,共14页
Patient with atrial fibrillation(AF)are at risk of developing stroke with the left atrial appendage(LAA)being the most common site for thrombus formation.If left untreated,AF is associated with 4 to 5 folds increase i... Patient with atrial fibrillation(AF)are at risk of developing stroke with the left atrial appendage(LAA)being the most common site for thrombus formation.If left untreated,AF is associated with 4 to 5 folds increase in the risk of ischemic stroke in all age groups.About 5%to 15%of AF patients have atrial thrombi on transesophageal echocardiography,and 91%of those thrombi are located in the LAA in patient with nonrheumatic AF.Although oral anticoagulants are the gold-standard treatment for stroke prevention in patients with non-valvular AF,some patients are at high risk of bleeding and deemed not candidates for anticoagulation.Therefore,LAA occlusion(LAAO)has emerged as alternative approach for stroke prevention in those patients.Surgical LAAO is associated with high rate of unsuccessful closure and recommended only in patients with AF and undergoing cardiac surgery.Percutaneous LAAO uses transvenous access with trans-septal puncture and was first tested using the PLAATO device.Watchman is the most common and only Food and Drug Administration(FDA)approved device for LAAO.LAAO using Watchman device is non-inferior to warfarin therapy in preventing ischemic stroke/systemic thromboembolism.However,it is associated with lower rates of hemorrhagic stroke,bleeding and death.Amplatzer is another successful LAAO device that has CE mark and is waiting for FDA approval.Optimal antithrombotic therapy post LAAO is still under debate and highly patient-specific.The aim of this paper is to systematically review the current literature to evaluate the efficacy and safety of different LAAO devices. 展开更多
关键词 LEFT ATRIAL appendage ATRIAL FIBRILLATION ANTICOAGULATION Stroke Mortality
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Anthocleistenolide B, a New Secoiridoid from <i>Anthocleista liebrechtsiana</i>De Wild &T. Durand 预览
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作者 Francis T. Ngouafong Roland T. Tchuenguem +6 位作者 Jonas Kühlborn Billy T. Tchegnitegni Beaudelaire K. Ponou Rémy B. Teponno Jean P. Dzoyem Till Opatz Léon A. Tapondjou 《生物化学进展(英文)》 2019年第4期135-142,共8页
Drug resistance due to the extensive abuse and over-use of antibiotics has become an increasingly serious problem and researchers started to use plants as an alternative source of new antibiotics. The aim of the prese... Drug resistance due to the extensive abuse and over-use of antibiotics has become an increasingly serious problem and researchers started to use plants as an alternative source of new antibiotics. The aim of the present study was to assess the antimicrobial properties of secondary metabolites isolated from A. liebrechtsiana. A new secoiridoid derivative, anthocleistenolide B (1), along with three known compounds, the monoterpene diol, djalonenol (2), the xanthone O-glycoside, decussatin 1-O-β-D-glucopyranoside and the fatty acid, dotriacontanoic acid (4) was isolated from the leaves and bark of this plant. Their structures were elucidated by extensive analysis of spectroscopic (1D and 2D NMR) and mass spectrometric data. The isolated compounds were screened for their antimicrobial properties against five strains of bacteria (two gram positive: Staphylococcus aureus 29213, Enterococcus faecalis ATCC 25922 and three gram negative: Escherichia coli ATCC51299, Proteus mirabilis (isolate), and Pseudomonas aeruginosa QC76110), but all were inactive. 展开更多
关键词 Anthocleista liebrechtsiana Anthocleistenolide B ANTIMICROBIAL Properties
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Do patients with gastroesophageal reflux disease and somatoform tendencies benefit from antireflux surgery? 预览
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作者 Hans Friedrich Fuchs Benjamin Babic +3 位作者 Karl-Hermann Fuchs Wolfram Breithaupt Gabor Varga Frauke Musial 《世界胃肠病学杂志:英文版》 SCIE CAS 2019年第3期388-397,共10页
BACKGROUND The clinical presentation of gastroesophageal reflux disease(GERD)shows a large symptom variation also in different intensities among patients.As several studies have shown,there is a large overlap in the s... BACKGROUND The clinical presentation of gastroesophageal reflux disease(GERD)shows a large symptom variation also in different intensities among patients.As several studies have shown,there is a large overlap in the symptomatic spectrum between proven GERD and other disorders such as dyspepsia,functional heartburn and/or somatoform disorders.AIM To prospectively evaluate the GERD patients with and without somatoform disorders before and after laparoscopic antireflux surgery.METHODS In a tertiary referral center for foregut surgery over a period of 3 years patients with GERD,qualifying for the indication of laparoscopic antireflux surgery,were investigated prospectively regarding their symptomatic spectrum in order to identify GERD and associated somatoform disorders.Assessment of symptoms was performed by an instrument for the evaluation of somatoform disorders[Somatoform Symptom Index(SSI)>17].Quality of life was evaluated by Gastrointestinal Quality of Life Index(GIQLI).RESULTS In 123 patients an indication for laparoscopic antireflux surgery was established and in 43 patients further medical therapy was suggested.The portion of somatoform tendencies in the total patient population was 20.48%(34 patients).Patients with a positive SSI had a preoperative GIQLI of 77(32-111).Patients with a normal SSI had a GIQLI of 105(29-140)(P<0.0001).In patients with GERD the quality of life could be normalized from preoperative reduced values of GIQLI 102(47-140)to postoperative values of 117(44-144).In patients with GERD and somatoform disorders,the GIQLI was improved from preoperative GIQLI 75(47-111)to postoperative 95(44-122)(P<0.0043).CONCLUSION Patients with GERD and associated somatoform disorders have significantly worse levels of quality of life.The latter patients can also benefit from laparoscopic fundoplication,however they will not reach a normal level. 展开更多
关键词 GASTROESOPHAGEAL REFLUX DISEASE ANTIREFLUX surgery Laparoscopic fundoplication SOMATIZATION GASTROESOPHAGEAL REFLUX DISEASE symptoms
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Increasing the value of weather-related warnings
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作者 Qinghong Zhang Liye Li +11 位作者 Beth Ebert Brian Golding David Johnston Brian Mills Shannon Panchuk Sally Potter Michael Riemer Juanzhen Sun Andrea Taylor Sarah Jones Paolo Ruti Julia Keller 《科学通报:英文版》 SCIE EI CSCD 2019年第10期647-649,共3页
Despite advances in forecasting and emergency preparedness, weather related disasters continue to cost many lives, to displace populations and to cause wide-spread damage. Therefore, High Impact Weather Project (HIWea... Despite advances in forecasting and emergency preparedness, weather related disasters continue to cost many lives, to displace populations and to cause wide-spread damage. Therefore, High Impact Weather Project (HIWeather), a 10-year research project (https://public.wmo.int/en/resources/buHetin/hiweather-10-yearresearch- project), was established in 2016 by WM0 (World Meteorology Organization) WWRP (World Weather Research Program: https://www.wmo.int/pages/prog/arep/wwrp/new/wwrp_new_en. html). HIWeather aimed at achieving dramatic improvements in the effectiveness of weather-related hazard warnings, following recent advancement in numerical weather prediction at km-scale and in disaster risk reduction. The implementation plan was developed under the concept of warning chain, which comprises all components and the connections between to a successful weather-hazards warning: observations, weather forecast, hazard forecast, impact forecast, the generation of warnings and decision making (Fig. 1). A successful warning relies on information produced by the meteorological and related physical sciences, thus its effectiveness of delivery depends on applications of social, behavioral and economic sciences. The workshop of WM0 High Impact Weather Project was held in Beijing during 20-22 November of 2018, attracted a diverse and interdisciplinary group of over 70 scientists from 25 countries in the broad field of physical and social science, during which all elements of the warning chain were discussed critically. 展开更多
关键词 Despite advances forecasting and EMERGENCY WEATHER RELATED DISASTERS
神经科学偏见效应:可重复性及其心理机制的探索 预览
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作者 殷继兴 胡传鹏 《心理科学进展》 CSSCI CSCD 北大核心 2019年第12期1988-1995,共8页
神经科学的发展对其他学科以及社会产生了重要的影响。虽然神经科学方法与行为研究方法都是探索人类心理与行为的有效手段并各有所长,但神经科学的研究结果却可能引起人们过度的解读和信任。研究者发现,当某一结论使用神经科学结果作为... 神经科学的发展对其他学科以及社会产生了重要的影响。虽然神经科学方法与行为研究方法都是探索人类心理与行为的有效手段并各有所长,但神经科学的研究结果却可能引起人们过度的解读和信任。研究者发现,当某一结论使用神经科学结果作为证据时,比使用行为科学结果或者心理生理学指标作为证据时更加让人信服,即使神经科学结果与该结论之间毫无关系,这种现象被称为神经科学偏见(neuroscience bias)。通过系统回顾近年来关于神经科学偏见的研究,我们发现:(1)虽然神经科学偏见存在可重复性的争论,但该效应确实存在;(2)神经科学偏见的产生可能是因为个体倾向于还原论的解释(即使用低层次、简单的机制来解释更高层次上的现象)及心理本质主义的影响(即人们认为心理与行为的本质是神经活动)。神经科学偏见反映了公众对科学结果解读的偏见,未来研究需要探讨这种偏见的心理机制,从而引导科学结果的正确解读和运用。 展开更多
关键词 神经科学偏见 神经法学 心理机制 可重复性
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Facile Synthesis of ZnO-Au Nanopetals and Their Application for Biomolecule Determinations
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作者 XIANG Siyuan MENG Qingnan +3 位作者 ZHANG Kai GU Yue LIU Wendong YANG Bai 《高等学校化学研究:英文版》 SCIE CAS CSCD 2019年第5期924-928,共5页
Using dextran as both reductant and stabilizing agent, nanopetals(ZnO-Au NPs) were easily synthesized and possessed a petal-like morphology. The feature structure and size of such ZnO-Au NPs were adjustable by regulat... Using dextran as both reductant and stabilizing agent, nanopetals(ZnO-Au NPs) were easily synthesized and possessed a petal-like morphology. The feature structure and size of such ZnO-Au NPs were adjustable by regulating the amount of chloroauric acid(HAuCl4). Moreover, the electrochemical property of the obtained NPs was evaluated by being immobilized on the glassy carbon electrode(GCE), which performed both high sensitivity and stability in dopamine(DA) determinations. Furthermore, the as-prepared ZnO-Au NPs could also detect DA and uric acid(UA) simultaneously in the mixture without interference, indicating good selectivity and showing promising potential in biosensing. 展开更多
关键词 ZNO AU nanoparticle Petal-like NANOCOMPOSITE ELECTROCHEMISTRY BIOMOLECULE determination
将预注册的重复实验纳入心理学研究方法的课程 预览
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作者 胡传鹏 《心理技术与应用》 2019年第5期261-262,265共3页
心理学界的可重复性问题是近年来的一个热点。从2011年到2016年,国际心理学界对可重复性问题的认识大致经历了暴露问题、否认/争论、接受和应对几个阶段。2011年到2012年间集中爆发了Bem的超感知觉研究、Stapel长期学术造假和老年启动(e... 心理学界的可重复性问题是近年来的一个热点。从2011年到2016年,国际心理学界对可重复性问题的认识大致经历了暴露问题、否认/争论、接受和应对几个阶段。2011年到2012年间集中爆发了Bem的超感知觉研究、Stapel长期学术造假和老年启动(elderly priming)重复失败等几个重大的事件。这些事件的集中爆发,将严重的重复危机暴露在心理学家的面前,成为了国际心理学界关注的热点问题。2013~2014年期间,不少期刊组织了专刊对可重复性问题进行了讨论,各种学术会议上也出现了相应的专题讨论。这一阶段中,主要讨论点在于:心理学研究中是否存在“可重复危机”?已经发现的重复失败问题是特殊现象还是心理学研究的常见现象?2015年开放科学合作组(Open Science Collobration)在《科学》杂志上发表的《对心理科学中可重复性的估计(Estimating the reproducibility of psychological science)》,发现2008年发表在《人格与社会心理学杂志( Journal of Personality and Social Psychology )》《实验心理学杂志:学习、记忆与认识( Journal of Experimental Psychology: Learning, Memory, and Cognition )》和《心理科学( Psychological Science )》三个杂志上的100篇文章的可重复性大约为39%,该文引起了广泛的关注。与此同时,美国心理科学协会(Association of Psychological Sciences,APS)也组织了预注册的重复报告(Registered Replication Reports, RRR),这些规范的、大规模的重复也发现了许多重要的研究无法重复。这些重复研究使得心理学研究者不得不接受一个事实:心理学中不可重复的研究,可能不是少数,而是很常见的。2016年开始,国际同行们开始更加认真地讨论如何应对可重复危机,包括在讨论可重复性危机时的语气(tone)的问题、如何开放数据、材料等。同一时间,越来越多的研究者开始使用开放科学框架(Open Science Framework, OSF),越来越多的杂 展开更多
关键词 心理学家 重复实验 注册 可重复性 心理科学 课程 MEMORY 《科学》
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社会经济地位对大脑结构与功能的影响
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作者 吕子旸 彭凯平 胡传鹏 《科学通报》 EI CAS CSCD 北大核心 2019年第20期2114-2126,共13页
社会经济地位(socioeconomic status, SES)与大脑结构和功能的关系对于理解社会经济因素对心理行为的影响以及预防大脑和心理疾病具有重要意义.在过去十多年中,研究者使用认知神经科学的方法对SES与大脑的关系进行了探索,发现SES与大脑... 社会经济地位(socioeconomic status, SES)与大脑结构和功能的关系对于理解社会经济因素对心理行为的影响以及预防大脑和心理疾病具有重要意义.在过去十多年中,研究者使用认知神经科学的方法对SES与大脑的关系进行了探索,发现SES与大脑结构和功能之间可能存在相关性,但这些研究的结果却不完全一致.本文从大脑结构与功能两个层次出发,按照认知与情绪两大主题对SES与大脑关系的认知神经科学研究进行回顾,在此基础上对比不同研究结果的异同之处.结果发现:(1)在脑结构上, SES水平与海马体(主要负责记忆)、前额叶(参与执行功能等高级认知过程)及皮层下结构(主要包括参与情绪加工的杏仁核等结构)可能存在相关;(2)在脑功能上,不同SES水平的个体在进行执行功能、学习和记忆等相关任务时,大脑活动模式可能存在差异,同时正性与负性情绪刺激所引发的大脑活动在不同SES水平的个体上可能有所差异.值得注意的是, SES与大脑关系的研究中还面临着诸多挑战,如SES测量的复杂性和全面性、大脑结构与功能自身发展和测量的复杂性、SES影响大脑机制的多层次性等.未来的研究需要应对上述的挑战,同时考虑文化差异等影响,从而能够更准确地理解SES与大脑的关系,并为中国社会治理政策提供指导. 展开更多
关键词 社会经济地位 大脑结构 大脑功能 认知能力 情绪加工 可重复性
Polycyclic aromatic hydrocarbons in the graphene era
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作者 Xiao-Ye Wang Xuelin Yao Klaus Mullen 《中国科学:化学英文版》 SCIE EI CAS CSCD 2019年第9期1099-1144,共46页
Polycyclic aromatic hydrocarbons(PAHs) have been the subject of interdisciplinary research in the fields of chemistry, physics,materials science, and biology. Notably, PAHs have drawn increasing attention since the di... Polycyclic aromatic hydrocarbons(PAHs) have been the subject of interdisciplinary research in the fields of chemistry, physics,materials science, and biology. Notably, PAHs have drawn increasing attention since the discovery of graphene, which has been regarded as the "wonder" material in the 21 st century. Different from semimetallic graphene, nanoscale graphenes, such as graphene nanoribbons and graphene quantum dots, exhibit finite band gaps owing to the quantum confinement, making them attractive semiconductors for next-generation electronic applications. Researches based on PAHs and graphenes have expanded rapidly over the past decade, thereby posing a challenge in conducting a comprehensive review. This study aims to interconnect the fields of PAHs and graphenes, which have mainly been discussed separately. In particular, by selecting representative examples, we explain how these two domains can stimulate each other. We hope that this integrated approach can offer new opportunities and further promote synergistic developments in these fields. 展开更多
关键词 POLYCYCLIC aromatic hydrocarbon GRAPHENE GRAPHENE NANORIBBON NANOGRAPHENE GRAPHENE quantum DOT carbon materials
Honeybees prefer novel insect-pollinated flower shapes over bird-pollinated flower shapes
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作者 Scarlett R. Howard Mani Shrestha +4 位作者 Juergen Schramme Jair E. Garcia Aurore AvARGUES-WEBER Andrew D. Greentree Adrian G. DYER 《动物学报:英文版》 SCIE CAS CSCD 2019年第4期457-465,共9页
Plant-pollinator in teractio ns have a fundame ntal in fluence on flower evolution. Flower color signals are frequently tuned to the visual capabilities of important pollinators such as either bees or birds, but far l... Plant-pollinator in teractio ns have a fundame ntal in fluence on flower evolution. Flower color signals are frequently tuned to the visual capabilities of important pollinators such as either bees or birds, but far less is known about whether flower shape in fluences the choices of pollinators. We tested European honeybee Apis mellifera pref ere nces using novel achromatic (gray-scale) images of 12 insect-pollinated and 12 bird-pollinated native Australian flowers in Germany;thus, avoiding in flue nces of color, odor, or prior experie nee. In depende nt bees were tested with a number of parameterized images specifically desig ned to assess pref ere nces for size, shape, brightness, or the number of flower-like shapes prese nt in an image. We show that honeybees have a pref ere nee for visiti ng images of in sect-polli nated flowers and such a pref ere nee is most-likely mediated by holistic in formati on rather than by in dividual image parameters. Our results in dicate an giosperms have evolved flower shapes which in fluence the choice behavior of importa nt pollinators, and thus suggest spatial achromatic flower properties are an important part of visual signaling for plantpollinator in teractions. 展开更多
关键词 ANGIOSPERM Apis MELLIFERA (European honeybee) bird-pollinated flower insect-pollinated POLLINATOR
Deep-elliptical-silver-nanowell arrays (d-EAgNWAs) fabricated by stretchable imprinting combining colloidal lithography: A highly sensitive plasmonic sensing platform
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作者 Xueyao Liu Wendong Liu Bai Yang 《纳米研究:英文版》 SCIE EI CAS CSCD 2019年第4期845-853,共9页
Elliptical metallic nanohole arrays possess much higher transmission and enhanced sensitivity compared with circular nanohole arrays.However,fabricating elliptical metallic nanohole arrays in large area with highly tu... Elliptical metallic nanohole arrays possess much higher transmission and enhanced sensitivity compared with circular nanohole arrays.However,fabricating elliptical metallic nanohole arrays in large area with highly tunable aspect ratio remains a challenge.Herein,a brand-new method combining stretchable imprinting with colloidal lithography is figured out to fabricate deep-elliptical-silver-nanowell arrays (d-EAgNWAs).In this method,large area highly ordered silicon nanopillar arrays fabricated by colloidal lithography were taken as a master to transfer large area polydimethylsiloxane (PDMS) nanohole arrays.Benefit from the high elasticity of PDMS mold,the aspect ratio of d-EAgNWAs achieved can be facilely regulated from 1.7 to 5.0.Through optimization of polarization direction and the structural parameters including nanowell depth,aspect ratio,and hole size,the sensing performance of d-EAgNWAs was finally improved up to 1,414.1 nm/RlU.The best sensing behaved d-EAgNWAs were employed as an immunoassay platform finally to prove their great potential in label-free biosensing. 展开更多
关键词 PLASMONIC sensor colloidal lithography nanohole deep-elliptical-silver-nanowell ARRAYS STRETCHABLE IMPRINTING
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