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Localization-limited exciton oscillator strength in colloidal CdSe nanoplatelets revealed by the optically induced stark effect

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Light(Science & Applications) 2021年第6期10卷 1122-1132页

作者： pieter Geiregat Carmelita Roda Ivo Tanghe Shalini Singh Alessio Di Giacomo Delphine Lebrun Gianluca Grimaldi jorick Maes Dries Van Thourhout Iwan Moreels Arjan j.Houtepen Zeger Hens Physics and Chemistry of Nanostructures Department of ChemistryGhent UniversityGentBelgium. Center for Nano and Biophotonics Ghent UniversityGentBelgium. Photonics Research Group Ghent UniversityGentBelgium. Department of Chemical Sciences and Bernal Institute University of LimerickLimerickIreland. Center for Nanophotonics NWO-lnstitute AMOLFScience Park 1041098 XG AmsterdamThe Netherlands. Opto-Electronic Materials Section Department of Chemical EngineeringDelft UniversityDelftThe Netherlands

2D materials are considered for applications that require strong light-matter interaction because of the apparently giant oscillator strength of the exciton transitions in the absorbance ***,the effective oscillator strengths of these transitions have bee n scarcely reported,nor is there a con sistent interpretati on of the obtained ***,we analyse the transition dipole moment and the ensuing oscillator strength of the exciton transition in 2D CdSe nanoplatelets by means of the optically induced Stark effect(OSE).Intriguingly,we find that the exciton absorption line reacts to a high intensity optical field as a transition with an oscillator strength FStark that is 50 times smaller than expected based on the linear absorption *** propose that the pronounced exciton absorption line should be seen as the sum of multiple,low oscillator strength transitions,rather than a single high oscillator strength one,a feat we assign to strong exciton center-of-mass *** the quantum mechanical description of excitons,this 50-fold difference between both oscillator strengths corresponds to the ratio between the cohere nee area of the exciton's center of mass and the total area,which yields a coherence area of a mere 6.1 *** we find that the coherence area in creases with reducing temperature,we conclude that thermal effects,related to lattice vibrations,contribute to exciton *** further support of this localization model,we show that FStark is in dependent of the n anoplatelet area,correctly predicts the radiative lifetime,and lines up for strongly confined quantum dot systems.

关键词： coefficient. spectrum. oscillator

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Tropical forest canopies and their relationships with climate and disturbance： results from a global dataset of consistent field-based measurements

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Forest Ecosystems 2018年第1期5卷 77-90页

作者： marion pfeifer alemu gonsamo william woodgate luis cayuela andrew r.marshall alicia ledo timothy c.e.paine rob marchant andrew burt kim calders colin courtney-mustaphi aida cuni-sanchez nicolas j.deere dereje denu jose gonzalez de tanago robin hayward alvaro lau manuel j.macía pieter i.olivier petri pellikka hamidu seki deo shirima rebecca trevithick beatrice wedeux charlotte wheeler pantaleo k.t.munishi thomas martin abdul mustari philip j.platts school of natural and environmental sciences newcastle universityUpon TyneNewcastle NE1 7RUUK department of geography and planning university of torontoONCanada land and water commonwealth scientific and industrial research organisationYarralumlaACTAustralia school of mathematical and geospatial sciences rmit universityGPO Box 2476VMelbourneVIC 3001Australia department of biology geologyphysics and inorganic chemistryuniversidad rey juan carlosE-28933 MostolesMadridSpain tropical forest and peopleresearch centre university of the sunshine coastsippy DownsAustralia environment department university of yorkYorkUK flamingo land ltd. MaltonUK the institute of biological and environmental sciences environmental modelling groupuniversity of aberdeenAberdeenUK biological and environmental sciences university of stirlingStirling FK9 4L AUK york institute for tropical ecosystems environment departmentuniversity of yorkYork YO10 5NGUK department of geography university college londonGower StreetLondon WC1E 6BTUK earth observation climate and optical groupnational physical laboratoryHampton RoadTeddingtonMiddlesex TW11 0LWUK department of archaeology and ancient history uppsala universitetP.O.Box 256-751 05 UppsalaSESweden center for macroecology evolution and climateuniversity of copenhagenUniversitetsparken 152100 CopenhagenDKDenmark durrell institute of conservation and ecology(dice) school of anthropology and conservationuniversity of kentCanterbury CT2 7NRUK department of biology college of natural sciencesjimma universityJimmaEthiopia wageningen university&research laboratory of geo-information science and remote sensingDroevendaalsesteeg 36708 PB Wageningenthe Netherlands center for international forestry research(cifor) Situ GedeSindang BarangBogor 16680Indonesia departamento de biología área de botánicauniversidad autónoma de madridcalle Darwin 2-28049 MadridESSpain conservation ecology research unit university of pretoriaHatfieldPretoriaSouth Af

Background： Canopy structure, defined by leaf area index （LAI）, fractional vegetation cover （FCover） and fraction of absorbed photosynthetically active radiation （fAPAR）, regulates a wide range of forest functions and ecosystem services. Spatially consistent field-measurements of canopy structure are however lacking, particularly for the tropics. Methods： Here, we introduce the Global LAI database： a global dataset of field-based canopy structure measurements spanning tropical forests in four continents （Africa, Asia, Australia and the Americas）. We use these measurements to test for climate dependencies within and across continents, and to test for the potential of anthropogenic disturbance and forest protection to modulate those dependences. Results： Using data collected from 887 tropical forest plots, we show that maximum water deficit, defined across the most arid months of the year, is an important predictor of canopy structure, with all three canopy attributes declining significantly with increasing water deficit. Canopy attributes also increase with minimum temperature, and with the protection of forests according to both active （within protected areas） and passive measures （through topography）. Once protection and continent effects are accounted for, other anthropogenic measures （e.g. human population） do not improve the model. Conclusions： We conclude that canopy structure in the tropics is primarily a consequence of forest adaptation to the maximum water deficits historically experienced within a given region. Climate change, and in particular changes in drought regimes may thus affect forest structure and function, but forest protection may offer some resilience against this effect.

关键词： Leaf area index Fractional vegetation cover Fraction of absorbed photosynthetically active radiation,Human population pressure Protected areas Drought Climate change

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荷兰地下水中的砷对饮用水供给的影响

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水资源保护 2010年第1期26卷 75-79,83页

作者：李志萍刘翠 pieter j.STUYFZAND D.Van HALEM 华北水利水电学院河南郑州450011 Delft University of Technology Stevinweg 12628 CN DelftThe Netherlands Kiwa Water Research PO Box 10723430 BB NieuwegeinNetherlands VU University De Boelelaan 10911081 HV Amsterdamthe Netherlands UNESCO-IHE Institute for Water Education Westvest 72611 AX DelftThe Netherlands

介绍了荷兰饮用水的供给状况,地下水中砷的分布,饮用水中的砷,以及8个典型水文系统中砷的形成过程、水化学特征,分析了荷兰地下水中砷的活动过程,主要包括:吸附和阴离子交换、黄铁矿的氧化反应和氧(氢氧)化铁的还原性溶解以及砷酸盐被... 详细信息

介绍了荷兰饮用水的供给状况,地下水中砷的分布,饮用水中的砷,以及8个典型水文系统中砷的形成过程、水化学特征,分析了荷兰地下水中砷的活动过程,主要包括:吸附和阴离子交换、黄铁矿的氧化反应和氧(氢氧)化铁的还原性溶解以及砷酸盐被还原成亚砷酸盐,并针对不同的情况提出了相应的治理措施。

关键词：砷地下水氧化还原反应吸附阴离子交换

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快速原位形成的生物水凝胶的合成及蛋白质释放

快速原位形成的生物水凝胶的合成及蛋白质释放

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2007年全国高分子学术论文报告会

作者：钟志远 Christine Hiemstra Rong jin pieter j.Dijkstra jan Feijen 苏州大学化学化工学院生物医用高分子材料实验室 Department of Polymer Chemistry and Biomaterials Institute for Biomedical Technology Faculty of Science and TechnologyUniversity of TwenteP.O.Box 2177500 AE Enschedethe Netherlands. Department of Polymer Chemistry and Biomaterials Institute for Biomedical Technology Faculty of Science and TechnologyUniversity of TwenteP.O.Box 2177500 AE Enschedethe Netherlands. Department of Polymer Chemistry and Biomaterials Institute for Biomedical Technology Faculty of Science and TechnologyUniversity of TwenteP.O.Box 2177500 AE Enschedethe Netherlands. Department of Polymer Chemistry and Biomaterials Institute for Biomedical Technology Faculty of Science and TechnologyUniversity of TwenteP.O.Box 2177500 AE Enschedethe Netherlands.

＜正＞水凝胶因良好的生物相容性和渗透性等在生物医学领域如药物／蛋白质的缓释、生物组织工程等展现了广阔的应用前景。近年来,我们从分子设计角度出发,研发了一系列新型、可注射性的、可生物降解的、原位形成的水凝胶。具体包括：热... 详细信息

＜正＞水凝胶因良好的生物相容性和渗透性等在生物医学领域如药物／蛋白质的缓释、生物组织工程等展现了广阔的应用前景。近年来,我们从分子设计角度出发,研发了一系列新型、可注射性的、可生物降解的、原位形成的水凝胶。具体包括：热敏性的水凝胶、八臂聚乙二

关键词：水凝胶可注射性的可生物降解原位形成蛋白质释放

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Adequate Diagnostic Performance of Combined [¹⁸F]-Fluormethylcholine PET-CT with Diffusion-Weighted MRI in Primary Staging of High Risk Prostate Cancer

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Advances in Molecular Imaging 2016年第1期6卷 1-9页

作者： pieter L. jager R. jorn Beukinga Tjard D. de Haan Martijn F Boomsma Ben E. Laddé Miranda van t Veer-ten Kate Ad H. j. Oostdijk Martijn G. Steffens Department of Nuclear Medicine Zwolle Netherlands Department of Urology Zwolle Netherlands Department of Radiology Zwolle Netherlands Department of Pathology Zwolle Netherlands

Introduction: [18F]-fluoro-methylcholine (FCH) PET/CT and MRI with diffusion-weighted MRI (DW-MRI) have insufficient performance in lymph node staging of primary prostate cancer by themselves, but the combination may perform better. We aim to prospectively determine the diagnostic performance of combined FCH PET and MRI for lymph node staging. Methods: This was a single site study of diagnostic accuracy in a well-defined group of 21 consecutive high-risk primary prostate cancer patients (>30% chance of lymph node metastases) in a large community hospital. We performed FCH PET/CT and MRI with DW-MRI prior to endoscopic extended pelvic lymph node dissection (EPLND). PET was fused and interpreted together with various MRI image sets (T1, T2, DWIBS) and was only scored positive when a lymph node seen on MRI coincided with increased focal FCH uptake on PET. Findings were compared with detailed histological evaluation, on a per-patient and per-region level. We calculated sensitivity, specificity, positive and negative predictive value of combined PET-MRI. Results: 14 out of 21 patients had metastatic lymph nodes with 37 out of 164 evaluable regions harboring metastases. On a per-patient analysis, PET-MRI had a sensitivity/specificity of 79/100% with a PPV/NPV of 100/77%. On a per-region analysis (n = 164) these figure were 65/99% and 96/91%, respectively. Conclusions: Combined DW-MRI and FCH PET/CT has a very high positive predictive value in high risk prostate cancer patients. If confirmed in larger series a positive combined scan may safely allow cancellation of surgical staging in selected patients, depending on local protocols in N1 M0 patients.

关键词： Positron Emission Tomography Diffusion-Weighted Imaging Fluor-Methyl-Choline Prostate Cancer Primary Staging

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营养发展的生物标志物——碘的综述

营养发展的生物标志物——碘的综述

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作者： Fabian Rohner Michael Zimmermann pieter jooste Chandrakant Pandav Kathleen Caldwell Ramkripa Raghavan Daniel j.Raiten Institute of Food Nutrition and HealthSwiss Federal Institute of Technology(ETH) Centre of Excellence for Nutrition Faculty of Health SciencesNorth-West University Centre for Community Medicine All India Institute of Medical Sciences National Center for Environmental Health CDC Eunice Kennedy Shriver National Institute of Child Health and Human Development NIH

营养发展生物标志物工程的目的是提供关于选择、使用和解释反映营养素暴露、状态、功能和效果的生物标志物的最前沿(先进)的信息和服务。具体而言,该项目旨在制定共识,寻求一个适用于研究人员(实验室/临床/监测),临床医生,程序员和政策...

营养发展生物标志物工程的目的是提供关于选择、使用和解释反映营养素暴露、状态、功能和效果的生物标志物的最前沿(先进)的信息和服务。具体而言,该项目旨在制定共识,寻求一个适用于研究人员(实验室/临床/监测),临床医生,程序员和政策制定者(数据消费者)准确的评估方法。该项目也旨在通过对相关生物系统中营养生物学更深入的理解制定有针对性的研究议程以支持生物标志物的发现和发展。在BOND工程的第一阶段,选择了6种有着重要公共卫生意义的营养素(碘、维生素A、铁、锌、叶酸、维生素B12),因为它们代表了用户在选择、使用和解释生物标志物时所面临的挑战。对于每一种营养素,会成立专家小组负责制定一个全面的审查,涵盖各自的营养素生物学,现有的生物标志物,以及具体使用的问题,特别是参考个别用户群体的需求。除了这些发表的综述,相关材料也会列在BOND互动网站上。本综述代表了第一系列的综述并覆盖了碘生物学和生物标志物的相关方面。本文就碘的背景历史作为一个公共卫生问题给读者做了一个完整的评价,并且回顾了它的生物学,可用的生物学标志物,具体使用注意事项以及一系列临床和基于人群运用碘生物标志物的解释。综述还包括了详细的研究议程,处理我们对碘生物学的理解和评价的鸿沟。

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CPB的冠脉手术病人主要麻醉方法的选择影响术后ICU住院时间

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国外医学（麻醉学与复苏分册） 2004年第4期25卷 249-252,256页

作者： Stefan G.De Hert Philippe j.Van der Linden Stefanie Cromheecke Roel Meeus pieter W.ten Broecke Ivo G.De Blier Bernard A.tockman Inez E.Rodrigus 刘功俭(译) 曾因明(审) Director of the Division of Cardiothoracic and Vascular Anesthesia University Hospital Antwerp Department of Anesthesiology University Hospital Antwerp Department of Anesthesiology Brugmann-HUDERF University Hospital BrusselsBelgium. Department of Cardiac Surgery University Hospital Antwerp 不详

研究背景:挥发性麻醉药在冠脉手术期间可以保护心肌.本研究旨在和全凭静脉麻醉相比较,说明挥发性麻醉药的应用与ICU住院天数和总住院天数(LOS)减少有关。

关键词： CPB 冠脉手术麻醉选择术后 ICU住院时间

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Is BMI Associated with Cardiorespiratory Fitness?A Cross-Sectional Analysis Among 8470 Apparently Healthy Subjects Aged 18-94 Years from the Low-Lands Fitness Registry

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journal of Science in Sport and Exercise 2022年第3期4卷 283-289页

作者： T.Takken H.j.Hulzebos Low-Lands Fitness Registry Study Group Child Development and Exercise Center Wilhelmina Children’s HospitalUniversity Medical Center UtrechtRoom KB02.056.0NLPO Box 850903508 AB UtrechtThe Netherlands

Objective The purpose of the present study was to investigate the association between cardiorespiratory fitness(CRF)measured as peak oxygen uptake(VO_(2peak),expressed in mL/min)and body mass index(BMI)in a large cohort of apparently healthy *** BMI and VO_(2peak)were measured in a cross-sectional study of 8470 apparently healthy ***_(2peak)(mL/min)was determined by an incremental cycle ergometer test to *** regression analyses were performed to identify predictors of *** There was no difference in CRF between adults with a normal weight(BMI between 18.5-24.9 kg/m^(2))and those who were overweight(BMI 25.0-29.9 kg/m^(2)).Subjects who were underweight(BMIjects with a BMIjects with a BMI between 18.5 and 29.9 kg/m^(2).In obese subjects,CRF was only lower in females compared to females with a BMI between 18.5 and 29.9 kg/m^(2).Correcting CRF for BMI may be beneficial for subjects with a low BMI,and females with a BMI≥30.0 kg/m^(2).The outcome of this study might help to improve the interpretation of exercise testing results in individuals with a low or high BMI.

关键词： Cardiorespiratory fitness Cardiopulmonary exercise testing Body mass index Maximal oxygen uptake Obesity Exercise test Oxygen consumption

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STRUCTURAL AND MAGNETIC CHARACTERISATION OF ORGANOMETALLIC SALTS OF TCNQ AND DCNQI

STRUCTURAL AND MAGNETIC CHARACTERISATION OF ORGANOMETALLIC S...

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Sixteenth Congress of the International Union of Crystallography

作者： R.Büchner j.S.Field R.j.Haines Department of Chemistry University of NatalP.O.Box 375Pieter-maritzburg 3200South Africa

The dinuclear electron-rich thiolato-bridged donor [FeCp*(CO)(μ-SEt)](Cp =pentamethylcyclopentadienide) reacts with TCNQ(7,7,8,8-tetracyanoquinodimethane) to afford the 1:1 charge-transfer salt [FeCp*(CO)(y-SEt)](TCNQ).X-ray diffraction studies reveal that the donor cations(D·+) and acceptor anions(A.-) stack in the crystal in the sequence ???D’A?~?D?-???with the anions present as diamagnetic pairs(TCNQ).the room temperature magnetic susceptibility confirms a S=1/2 ***

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全球史的宏观显微镜:Seshat全球史数据库的方法论梳理

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全球史评论 2020年第2期 -页

作者： [英]皮耶特·弗朗索瓦 [美]j.G.曼宁 [英]哈维·怀特豪斯 [爱]罗布·布伦南 [英]托马斯·柯里 [爱]凯文·费尼 [美]彼得·特钦闵超(译) 赫特福德大学牛津大学耶鲁大学都柏林大学三一学院埃克塞特大学彭林校区康涅狄格大学南京大学信息管理学院

本文介绍了"Seshat全球史数据库"项目及其所基于的方法论,以及它作为历史学者与其他人文学者一种研究工具的潜力。Seshat是一个综合性数据集,涵盖了自新石器时代以来人类文化演进的数据。本文详细描述了如何运用Seshat方法和平台来研究... 详细信息

本文介绍了"Seshat全球史数据库"项目及其所基于的方法论,以及它作为历史学者与其他人文学者一种研究工具的潜力。Seshat是一个综合性数据集,涵盖了自新石器时代以来人类文化演进的数据。本文详细描述了如何运用Seshat方法和平台来研究长时段尺度下的重要问题,同时让用户能够深入钻研细节、将每个数据点置于历史与史学编纂的情景之中。因此,Seshat为长时段历史研究提供了一个以严格方法论为基础的平台,本文也提倡人文与社科学者参与到基于数据驱动的长时段历史研究中来。本文认为,Seshat提供了一个急需的基础设施,在此之上,不同技能和学科背景的学者能够协同从长时段尺度分析过往历史。除了论及理论与方法论的支撑,本文还通过三个研究案例证明了Seshat的潜力。每一个案例都围绕着一系列长期存在的研究议题与史学争议,而Seshat的引入被认为有望彻底改变我们对这些议题的理解。

关键词：数据采集方法论数据提取全球史

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