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Mercury photoreduction and photooxidation in lakes：Effects of filtration and dissolved organic carbon concentration

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journal of Environmental Sciences 2018年第6期30卷 151-159页

作者： Nelson j.O’Driscoll Emma Vost Erin Mann Sara Klapstein robert Tordon Matthew Lukeman Department of Earth & Environmental Science Acadia University Wolfville B4P 2R6 Nova Scotia Canada Environment Canada Dartmouth Nova Scotia Canada Department of Chemistry Acadia University Wolfville B4P 2R6 Nova Scotia Canada

Mercury is a globally distributed, environmental contaminant. Quantifying the retention and loss of mercury is integral for predicting mercury-sensitive ecosystems. There is little information on how dissolved organic carbon（DOC） concentrations and particulates affect mercury photoreaction kinetics in freshwater lakes. To address this knowledge gap,samples were collected from ten lakes in Kejimkujik National Park, Nova Scotia（DOC： 2.6–15.4 mg/L）. Filtered（0.2 μm） and unfiltered samples were analysed for gross photoreduction, gross photooxidation, and net reduction rates of mercury using pseudo first-order curves. Unfiltered samples had higher concentrations（p = 0.04） of photoreducible divalent mercury（Hg（II）RED）（mean of 754 ± 253 pg/L） than filtered samples（mean of 482 ± 206 pg/L）;however, gross photoreduction and photooxidation rate constants were not significantly different in filtered or unfiltered samples in early summer. DOC was not significantly related to gross photoreduction rate constants in filtered（R2= 0.43; p = 0.08） and unfiltered（R2= 0.02; p = 0.71） samples; DOC was also not significantly related to gross photooxidation rate constants in filtered or unfiltered samples. However, DOC was significantly negatively related with Hg（Ⅱ）RED in unfiltered（R2= 0.53; p = 0.04）, but not in filtered samples（R2= 0.04;p = 0.60）. These trends indicate that DOC is a factor in determining dissolved mercury photoreduction rates and particles partially control available Hg（Ⅱ）RED in lake water. This research also demonstrates that within these lakes gross photoreduction and photooxidation processes are close to being in balance. Changes to catchment inputs of particulate matter and DOC may alter mercury retention in these lakes and could partially explain observed increases of mercury accumulation in biota.

关键词： Mercury Photoreduction Photooxidation Dissolved organic carbon(DOC) Particulates Kejimkujik National Park

Mapping microstructure to shock-induced temperature fields using deep learning

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npj Computational Materials 2023年第1期9卷 516-523页

作者： Chunyu Li juan Carlos Verduzco Brian H.Lee robert j.Appleton Alejandro Strachan School of Materials Engineering Purdue UniversityWest LafayetteIN 47907USA

The response of materials to shock loading is important to planetary science,aerospace engineering,and energetic *** activated processes,including chemical reactions and phase transitions,are significantly accelerated by energy localization into *** result from the interaction of the shockwave with the materials’microstructure and are governed by complex,coupled processes,including the collapse of porosity,interfacial friction,and localized plastic *** mechanisms are not fully understood and the lack of models limits our ability to predict shock to detonation transition from chemistry and microstructure *** demonstrate that deep learning can be used to predict the resulting shock-induced temperature fields in composite materials obtained from large-scale molecular dynamics simulations with the initial microstructure as the only *** accuracy of the Microstructure-Informed Shock-induced Temperature net(MISTnet)model is higher than the current state of the art and its evaluation requires a fraction of the computation cost.

关键词： microstructure Microstructure friction

Morphology and efficiency enhancements of PTB7-Th:ITIC nonfullerene organic solar cells processed via solvent vapor annealing

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journal of Energy Chemistry 2019年第10期28卷 148-156页

作者： robert S. Gurney Wei Li Yu Yan Dan Liu Andrew j. Pearson Tao Wang School of Materials Science and Engineering Wuhan University of TechnologyWuhan 430070HubeiChina State Key Laboratory of Silicate Materials for Architectures Wuhan University of TechnologyWuhan 430070HubeiChina Cavendish Laboratory University of CambridgeJ. J. Thomson AvenueCambridge CB3 0HEUK

The nanoscale morphology within the photoactive layer of organic solar cells is critical in determining the power conversion efficiency (PCE). Here, we draw attention to the roles of molecular arrangement, and domain size in improving performance, which can be tuned by subjecting the photovoltaic materials to solvent vapor annealing (SVA). In our PTB7-Th:ITIC devices, the PCE can be improved by exposing the device to solvent vapor for 60 s after solution casting. The solvent vapor prolongs reorganizational time and increases molecular ordering and domain size/phase separation, which are sub-optimal in pristine PTB7-Th:ITIC blend films. This improved morphology results in better charge mobility, reduced recombination, and ultimately an improved PCE from 7.1% to 7.9% when using CS2 as the annealing solvent. This simple SVA technique can be applied to a range of OPV systems where the molecular ordering is inferior within the as-cast photoactive layer.

关键词： Polymer solar cells Non-fullerene Solvent vapor annealing

Biodegradable stent or balloon dilatation for benign oesophageal stricture: Pilot randomised controlled trial

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World journal of Gastroenterology 2014年第48期20卷 18199-18206页

作者： Anjan Dhar Helen Close Yirupaiahgari K Viswanath Colin j Rees Helen C Hancock A Deepak Dwarakanath Rebecca H Maier Douglas Wilson james M mason Department of Gastroenterology County Durhamand Darlington NHS Foundation Trust Co. Durham DL14 6ADUnited Kingdom Durham Clinical Trials Unit School of Medicine Pharmacy and Health Durham University Queen’s Campus Wolfson Research Institute University Boulevard Stockton-on-Tees TS17 6BH United Kingdom Department of Surgery James Cook University Hospital Marton Road Middlesbrough TS4 3BW United Kingdom Department of Gastroenterology South Tyneside Hospitals NHS Foundation Trust Harton Lane South Shields NE34 0PL United Kingdom Department of Gastroenterology University Hospitals of North Tees Hardwick Stockton on Tees TS19 8PE United Kingdom

AIM: To undertake a randomised pilot study comparing biodegradable stents and endoscopic dilatation in patients with strictures.

关键词： Benign oesophageal stricture Biodegradable stent Endoscopic balloon dilatation Pilot study Randomised controlled trial Dysphagia

Electron excitation processes in low energy collisions of hydrogen-helium atoms

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Chinese Physics B 2022年第12期31卷 213-218页

作者： Kun Wang Chuan Dong Yi-Zhi Qu Ling Liu Yong Wu Xu-Hai Hong robert j.Buenker Institute of Environmental Science Shanxi UniversityTaiyuan 030006China College of Optoelectronics University of Chinese Academy of SciencesBeijing 100049China National Key Laboratory of Computational Physics Institute of Applied Physics and Computational MathematicsBeijing 100088China School of Physics and Electronic Technology Liaoning Normal UniversityDalian 116029China Fachbereich C-Mathematik und Naturwissenschaften Bergische Universitat WuppertalD-42097 WuppertalGermany

The electron excitation processes of H(1s)+He(1s^(2))→H(2s/2p)+He(1s^(2))are studied in impact energy range of 20-2000 e V/u by using the quantum-mechanical molecular orbital close-coupling(QMOCC)*** and state-selective cross sections have been obtained and compared with the available theoretical and experimental *** results agree well with available measurements in the overlapping energy regions *** comparison of our results with other theoretical calculations further demonstrates the importance of considering a sufficient number of *** datasets presented in this paper,including the excitation cross sections,are openly available at https://***/10.57760/sciencedb.j00113.00083.

关键词： electron excitation processes low energy collision quantum-mechanical molecular orbital close-coupling method cross section

Impact of exome sequencing in inflammatory bowel disease

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World journal of Gastroenterology 2013年第40期19卷 6721-6729页

作者： Christopher j Cardinale judith R Kelsen robert N Baldassano Hakon Hakonarson Center for Applied Genomics Children’s Hospital of PhiladelphiaAbramson Research Center Suite 1216PhiladelphiaPA 19104United States Division of Gastroenterology Hepatologyand NutritionDepartment of PediatricsChildren’s Hospital of PhiladelphiaPerelman School of Medicine at the University of PennsylvaniaPhiladelphiaPA 19104United States

Approaches to understanding the genetic contribution to inflammatory bowel disease(IBD)have continuously evolved from family-and population-based epidemiology,to linkage analysis,and most recently,to genome-wide association studies(GWAS).The next stage in this evolution seems to be the sequencing of the exome,that is,the regions of the human genome which encode *** GWAS approach has been very fruitful in identifying at least 163 loci as being associated with IBD,and now,exome sequencing promises to take our genetic understanding to the next *** this review we will discuss the possible contributions that can be made by an exome sequencing approach both at the individual patient level to aid with disease diagnosis and future therapies,as well as in advancing knowledge of the pathogenesis of IBD.

关键词： Sequencing Exome Genetics Inflammatory bowel disease

Primary feather vane asymmetry should not be used to predict the flight capabilities of feathered fossils

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Science Bulletin 2017年第18期62卷 1227-1228页

作者： Xia Wang robert L.Nudds Colin Palmer Gareth j.Dyke School of Biological Science and Technology University of Jinan Faculty of Life Sciences University of Manchester Department of Earth Sciences University of Bristol Evolutionary Zoology University of Debrecen

Reconstructing flight abilities of fossil birds from preserved wings and feathers is an important goal if we are to understand the evolution of ***-shape is known to correlate well with bird flight style[1],but functional wing-shape is almost impossible to reconstruct from fossils with a high degree of *** contrast,however,individual primary feathers are often

关键词：飞行能力不对称性羽毛化石预测应用高度确定诊断工具

Extensor pollicis brevis tendon can hyperextend thumb interphalangeal joint in absence of extensor pollicis longus:Case report and review of the literature

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World journal of Orthopedics 2016年第7期7卷 448-451页

作者： robert j Strauch Carolyn B Strauch Department of Orthopaedic Surgery Columbia University Dartmouth College

We are reporting a case of extensor pollicis longus tendon rupture which did not require tendon transfer owing to the ability of the intact extensor pollicis brevis(EPB) to fully hyperextend the thumb interphalangeal joint. The thumb metacarpophalangeal joint was also able to be fully actively extended by the EPB. Previous anatomical studies have demonstrated that the insertional anatomy of the EPB tendon is highly variable and sometimes inserts onto the extensor hood and distal phalanx, which is likely the mechanism by which our patient was able to fully extend the thumb interphalangeal joint. Despite the potential for the EPB to extend the IP joint of the thumb, virtually all previously reported cases of extensor pollicis longus(EPL) tendon rupture had deficits of thumb IP extension requiring tendon transfer. This case highlights the potential ability of the EPB tendon to completely substitute for the function of the EPL tendon in providing thumb IP joint extension.

关键词： Extensor pollicis brevis Extensor pollici longus Tendon rupture Extensor pollicis longus tendon rupture

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Open lung in ARDS

Acta Pharmacologica Sinica 2003年第12期 130-133页

作者： jack j HAITSMA,robert A LACHMANN,Burkhard LACHMANN Deptartment of Anesthesiology Erasmus Medical Center Rotterdam Rotterdam The Netherlands Deptartment of Anesthesiology Erasmus Medical Center Rotterdam Rotterdam The Netherlands Deptartment of Anesthesiology Erasmus Medical Center Rotterdam Rotterdam The Netherlands

Every year, millions of patients worldwide receive ventilator support during surgery. Mechanical ventilation has become an important therapy in the treatment of patients with impaired pulmonary function and particularly in patients suffering from adult respiratory distress syndrome （ARDS）. ARDS is caused by multiple factors and is characterized by respiratory dysfunction including hypoxemia and decreased lung compliance. It is known that the decrease in lung distensibility is due to a disturbed surfactant system with an elevated surface tension. This increase in surface tension leads to an increase in forces acting at the air-liquid interface, resulting finally in endexpiratory collapse, atelectasis, an increase in right-to-left shunt and a decrease in PaO2.

关键词： lung it on or as ARDS Open lung in ARDS in