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Physical activity, sedentary behavior, and long-term cardiovascular risk in young people: A review and discussion of methodology in prospective studies

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Journal of Sport and Health Science 2016年第2期5卷 145-150页

作者： Jakob Tarp Jan Christian Br?nd lars bo andersen Niels Christian M?ller Karsten Froberg Anders Gr?ntved Research Unit for Exercise Epidemiology Centre of Research in Childhood Health Department of Sport Science and Clinical BiomechanicsUniversity of Southern Denmark Department of Sports Medicine Norwegian School of Sport Sciences

The long-term effects of physical activity （PA） or sedentary behavior on cardiovascular health in young people are not well understood. In this study, we use a narrative format to review the evidence for a prospective association with adiposity and other well-established biological cardiovascular risk factors in healthy young people, considering only studies with at least 2 years of follow-up. PA appears to elicit a long-term beneficial effect on adiposity and particularly markers of cardiovascular health. With adiposity, however, a few studies also reported that higher levels of PA were associated with higher levels of adiposity. Time spent sedentary does not appear to be related to adiposity or markers of cardiovascular health independent of PA. We then discuss the uncertainties in the underlying causal chain and consider a number of alternative modeling strategies, which could improve our understanding of the relationship in future studies. Finally, we consider the current methodology for assessing PA and sedentary time.

关键词： Adiposity Adolescents Cardiovascular health Children Long-term Metabolic syndrome score

Real-time visualization of 3D city models at street-level based on visual saliency

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Science China Earth Sciences 2015年第3期58卷 448-461页

作者： MAO bo BAN YiFang lars HARRIE Jiangsu Provincial Key Laboratory of E-Business Nanjing University of Finance and Economics College of Computer Science and Engineering Nanjing University of Science and Technology Department of Urban Planning and Environment KTH Royal Institute of TechnologySE-10044 StockholmSweden Department of Physical Geography and Ecosystem Science Lund UniversityBox118SE-223 62 LundSweden

Street-level visualization is an important application of 3D city *** to street-level visualization include the cluttering of buildings due to fine detail and visualization *** this paper,a novel method is proposed for streetlevel visualization based on visual saliency *** basic idea of the method is to preserve these salient buildings in a scene while removing those that are *** method can be divided into pre-processing procedures and real-time *** first step in pre-processing is to convert 3D building models at higher Levels of Detail(Lo Ds) into LoD 1 models with simplified ground ***,a number of index viewpoints are created along the streets; these indices refer to both the position and the direction of each street site.A visual saliency value is computed for each building,with respect to the index site,based on a visual difference between the original model and the generalized *** calculate and evaluate three methods for visual saliency:local difference,global difference and minimum projection *** real-time visualization process begins by mapping the observer to its closest *** street view is then generated based on the building information stored in those indexes.A user study shows that the local visual saliency method performs better than do the global visual saliency,area and image-based methods and that the framework proposed in this paper may improve the performance of 3D visualization.

关键词： 3D city models street level visualization index viewpoints visual saliency

Potential Significance of the EU Water Framework Directive to China

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人民长江 2009年第8期40卷 54-62页

作者： lars Skov andersen Martin Griffiths EU China River Basin Management Advisory Team

The European Union Water Framework Directive (EU WFD) is a unique piece of legislation, which may be of great significance to on-going reforms of the water sector in China. First and foremost it unites 27 European member states behind a common goal, which is "to achieve good chemical and ecological status" of all water bodies across the EU. Other significant characteristics of the EU WFD are that (1) it sets a clear timeframe with a number of time-bound actions for member states to achieve the goal, but leaves it to member states to achieve this goal in a decentralised process, which makes allowance for the different socio-economic conditions, (2) it defines the river basin as the management unit for water thus departing with the traditional fragmented management by administrative units and it appoints a single competent authority for water management within each river basin, thus facilitating resolution of sector conflicts, (3) it requires a financial and economic analysis of the costs of implementing the EU WFD to enable decision makers to assess whether the required improvements are affordable to government and to the population within the river basin, and (4) it requires a structured process for information and consultation with stakeholders and the public throughout the planning and implementation process.

关键词： Potential Significance of the EU Water Framework Directive to China EU

Effects of vegetables and fruit with varying physical damage, fungal infection, and soil contamination on stability of aqueous ozone

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Food Bioscience 2022年第6期50卷 1758-1765页

作者： Sorivan Chhem-Kieth lars Holm Rasmussen Mette Rosenfjeld Mogens larsen andersen Department of Food Science University of CopenhagenFrederiksbergDenmark Department of Technology University College CopenhagenCopenhagenDenmark

The application of aqueous solutions of ozone for surface disinfection is an effective novel green technology with a potential for replacing the use of persistent chemicals in postharvest treatments. However, successful disinfection requires certain levels of ozone to be maintained throughout the process. The decay rates of aqueous ozone were found to vary with the presence of different fruit and vegetables commodities (apples, carrots, onions, celeriac, and pears). Pure aqueous ozone had a half-life of 3200 s, whereas the half-life of ozone was found to range with increasing cross-cut areas between 2177 and 291 s for apples, 573 and 345 s for carrots, 541 and 113 s for onions, 2800 and 253 s for pears, and 362 and 165 s for celeriac. With soil particles present, the ozone half-life dropped to 59 s for celeriac. Parallel measurements reported strong to moderate effect of soil particles (51–626 s, 10 g soil/L ozonated water), and naturally occurring fungi (850–2294 s, 0.25 g fungi mix/L ozonated water) on ozone half-life. In summary, presence of organic compounds, notably by damaged commodities, increase ozone decay and illustrate the need to correctly identify important ozone-depleting parameters, which is crucial for understanding the efficiency of ozone-based washing systems.

关键词： Postharvest cleaning Ozone decay Ozonated water

Arrested Development in Beirut： Migration, Security and Dilemmas of Consociational Democracy

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International Relations and Diplomacy 2017年第10期5卷 594-606页

作者： lars Erslev andersen Dansk Institut for Intemationale Studier Copenhagen Denmark

This article analyses two major dilemmas in contemporary Lebanon： Firstly, based on the theory of consociational democracy it identifies an increasing divide between the state that is building on a national security consensus among the power sharing elites and the society, which suffering from the political paralysis concerning reforms is depending on the market, the private initiative and the international donor community in coping with the challenges rooted in inadequate infrastructure, failing public services, corruption, and migration including the influx of Syrian refugees. Secondly, it discusses the contradiction between the cosmopolitan self-image of Beirut versus social exclusion of Palestinians, Asian and African migrant workers, and sexual minorities. Even if the Lebanese government points to terrorism and the refugees crisis as the biggest threats to the Lebanese state a closer analysis points to the increasing divide between state and society, which leads to a rise to a social crisis that involves all layers in the Lebanese society except the elite. Much of the discontent with this situation among Lebanese citizens and the Palestinians is today directed against the Syrians who are portrayed as the roots of the problems in Lebanon. It is an open question though that how long time the Lebanese society accept this narrative： the mass mobilization behind first You Stink movement in 2015 and then Beirut Madinati in 2016 indicates a political awareness in Beirut that holds the government and political system responsible for the huge problems and at the same time acknowledges that political reforms leading to a better economic distribution of Lebanese resources and power sharing not only for the elites but for the Lebanese society as such is the only way ahead and the best bulwark against a breakdown of the state.

关键词： consociational democracy migration Syrian refugees urban development security Beirut

Using motion capture to assess colonoscopy experience level

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World Journal of Gastrointestinal Endoscopy 2014年第5期6卷 53-59页

作者： Morten bo Svendsen Louise Preisler Jens Georg Hillingsoe lars bo Svendsen lars Konge Centre for Clinical Education University of Copenhagen and the Capital Region of Denmark Department of Surgical Gastroenterology Rigshospitalet and University of Copenhagen

AIM: To study technical skills of colonoscopists using a Microsoft Kinect? for motion analysis to develop a tool to guide colonoscopy ***: Ten experienced endoscopists(gastroenterologists, n = 2; colorectal surgeons, n = 8) and 11 novices participated in the study. A Microsoft Kinect? recorded the movements of the participants during the insertion of the colonoscope. We used a modified script from Microsoft to record skeletal data. Data were saved and later transferred to MatLab for analysis and the calculation of statistics. The test was performed on a physical model, specifically the "Kagaku Colonoscope Training Model"(Kyoto Kagaku Co. Ltd, Kyoto, Japan). After the introduction to the scope and colonoscopy model, the test was performed. Seven metrics were analyzed to find discriminative motion patterns between the novice and experienced endoscopists: hand distance from gurney, number of times the right hand wasused to control the small wheel of the colonoscope, angulation of elbows, position of hands in relation to body posture, angulation of body posture in relation to the anus, mean distance between the hands and percentage of time the hands were approximated to each ***: Four of the seven metrics showed discriminatory ability: mean distance between hands [45 cm for experienced endoscopists(SD 2) vs 37 cm for novice endoscopists(SD 6)], percentage of time in which the two hands were within 25 cm of each other [5% for experienced endoscopists(SD 4) vs 12% for novice endoscopists(SD 9)], the level of the right hand below the sighting line(z-axis)(25 cm for experienced endoscopists vs 36 cm for novice endoscopists, P < 0.05) and the level of the left hand below the z-axis(6 cm for experienced endoscopists vs 15 cm for novice endoscopists, P < 0.05). By plotting the distributions of the percentages for each group, we determined the best discriminatory value between the groups. A pass score was set at the intersection of the distributions, and

关键词： Colonoscopy Assessment Simulation Motion-capture Motion-analysis

A crosslinked polymer as dopant-free hole-transport material for efficient n-i-p type perovskite solar cells

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Journal of Energy Chemistry 2021年第4期30卷 211-218页

作者： Linqin Wang Fuguo Zhang Tianqi Liu Wei Zhang Yuanyuan Li Bin Cai Lanlan He Yu Guo Xichuan Yang bo Xu James M.Gardner lars Kloo Licheng Sun Organic Chemistry Centre of Molecular DevicesDepartment of ChemistryKTH Royal Institute of TechnologySE-10044 StockholmSweden Applied Physical Chemistry Centre of Molecular DevicesDepartment of ChemistryKTH Royal Institute of TechnologySE-10044 StockholmSweden Wallenberg Wood Science Centre Department of Fibre and Polymer TechnologyKTH Royal Institute of TechnologySE-10044 StockholmSweden State Key Laboratory of Fine Chemicals Institute of Artificial PhotosynthesisDUT-KTH Joint Education and Research Centre on Molecular DevicesDalian University of TechnologyDalian 116024LiaoningChina

A new crosslinked polymer,called P65,with appropriate photo-electrochemical,opto-electronic,and thermal properties,has been designed and synthesized as an efficient,dopant-free,hole-transport material(HTM)for n-i-p type planar perovskite solar cells(PSCs).P65 is obtained from a low-cost and easily synthesized spiro[fluorene-9,90-xanthene]-30,60-diol(SFX-OH)-based monomer X65 through a freeradical polymerization *** combination of a three-dimensional(3 D)SFX core unit,holetransport methoxydiphenylamine group,and crosslinked polyvinyl network provides P65 with good solubility and excellent film-forming *** employing P65 as a dopant-free hole-transport layer in conventional n-i-p type PSCs,a power conversion efficiency(PCE)of up to 17.7%is *** the best of our knowledge,this is the first time a 3 D,crosslinked,polymeric dopant-free HTM has been reported for use in conventional n-i-p type *** study provides a new strategy for the future development of a 3 D crosslinked polymeric dopant-free HTM with a simple synthetic route and low-cost for commercial,large-scale applications in future PSCs.

关键词： Perovskite solar cell Hole-transport material Dopant-free Crosslinked polymer Spiro[fluorene-9,9’-xanthene](SFX)

Unprecedented differences in the diamond nucleation density between carbon-and silicon-faces of 4H-silicon carbides

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Chinese Chemical Letters 2020年第7期31卷 2013-2018页

作者： bo Wang Pitsiri Sukkaew Guichen Song Andreas Rosenkranz Yunxiang Lu Kazhihito Nishimura Jia Wang Jilei Lyu Yang Cao Jian Yi lars Ojamae He Li Nanjiang Key Laboratory of Marine New Materials and Related Technology Zhejiang Key Laboratory of Marine Materials and Protection TechnologyNingbo Institute of Material Technology&EngineeringChinese Academy of SciencesNingbo 315201China Department of Physics Chemistryand BiologyLinkoping UniversitySE-58183 LinkopingSweden Department of Chemical Engineering Biotechnology and MaterialsUniversidad de ChileAvenida Beauchef 851SantiagoChile Mechanical Systems Engineering Kogakuin UniversityTokyo 192-0015Japan Department of Mechanical and Materials Engineering University of Nebraska-LincolnLincolnNE 68588United State

4H-silicon carbides deposited by diamond films have wide applications in many fields such as semiconductor heterojunction,heat sink and mechanical *** plays a critical role in the deposition of the diamond film on 4H-silicon ***,as a typical polar material,the fundamental mechanism of diamond nucleation on different faces of 4H-silicon carbides has not been fully understood *** this contribution,nucleation of diamond was performed on the carbon-and silicon-faces of 4H-silicon carbides in a direct current chemical vapor deposition *** nucleation density on the carbon-face is higher by 2-3 orders of magnitude compared to the *** electron microscopy verifies that there are high density diamond nuclei on the interface between the carbon-face and the diamond film,which is different from columnar diamond growth structure on the *** state theory calculation reveals that the unprecedented distinction of the nucleation density between the carbon-face and the silicon-face is attributed to different desorption rates of the absorbed hydrocarbon *** addition,kinetic model simulations demonstrate that it is more difficult to form CH2(s)-CH2(s)dimers on silicon-faces than carbon-faces,resulting in much lower nucleation densities on silicon-faces.

关键词： 4H-silicon carbide Diamond nucleation mechanism Transmission electron microscopy Transition state theory Kinetic model simulation

A novel phenoxazine-based hole transport material for efficient perovskite solar cell

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Journal of Energy Chemistry 2015年第6期24卷 698-706页

作者： Ming Cheng Cheng Chen bo Xu Yong Hua Fuguo Zhang lars Kloo Licheng Sun Department of Chemistry Organic ChemistryKTH Royal Institute of Technology Department of Chemistry Applied Physical ChemistryKTH Royal Institute of Technology State Key Laboratory of Fine Chemicals Institute of Artificial PhotosynthesisDUT–KTH Joint Education and Research Centre on Molecular DevicesDalian University of Technology (DUT)

Based on the previous research work in our laboratory, we have designed and synthesized a small-molecule, hole transport material （HTM） POZ6-2 using phenoxazine （POZ） as central unit and dicyanovinyl units as electron-withdrawing terminal groups. Through the introduction ofa 2-ethyl-hexyl bulky chain into the POZ core unit, POZ6-2 exhibits good solubility in organic solvents. In addition, POZ6-2 possesses appropriate energy levels in combination with a high hole mobility and conductivity in its pristine form. Therefore, it can readily be used as a dopant-flee HTM in perovskite solar cells （PSCs） and a conversion efficiency of 10.3% was obtained. The conductivity of the POZ6-2 layer can be markedly enhanced via doping in combination with typical additives, such as 4-tert-butylpyridine （TBP） and lithium bis（trifluoromethanesulfonyl） imide （LiTFS1）. Correspondingly, the efficiency of the PSCs was further improved to 12.3% using doping strategies. Under the same conditions, reference devices based on the well-known HTM Spiro-OMeTAD show an efficiency of 12.8%.

关键词： Dopant-flee Perovskite solar cell Hole transport material Phenoxazine Thin fiim