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Improved estimation of pM_(2.5) brown carbon contributions to filter light attenuation

particuology 2021年第3期19卷 1-9页

作者： Judith c.chow L.-W.Antony chen Xiaoliang Wang Mark c.Green john G.Watson Division of Atmospheric Sciences Desert Research InstituteRenoNVUSA State Key Laboratory of Loess and Quaternary Geology Institute of Earth EnvironmentChinese Academy of SciencesXi’anChina Graduate Faculty Department of Atmospheric SciencesUniversity of NevadaReno NevadaUSA Department of Environmental and Occ.p.tional Health School of Public HealthUniversity of NevadaLas VegasNVUSA

Multiwavelength light attenuation measurements have been acquired as part of thermal/optical carbon analysis in the *** Speciation Network(cSN)and the Interagency Monitoring of pROtected Visual Environments(IMpROVE)network beginning in *** are used to estimate pM_(2.5)brown carbon(Brc)contributions to light absorption at various wavelengths,a useful method for separating biomass burning contributions from other *** of light transmitted through the filter deviates from Beers Law as the mass of light absorbing materials *** study estimates the effects of these deviations with empirical adjustment factors applied to samples for cSN from 2016 to 2017 and for IMpROVE from 2016 to *** for the filter loading effect results in an annual average increase of∼6-7%Brc contribution to light attenuation:from 3.6%to 10.7%for the urban,more heavily loaded cSN samples;and from 23.7%to 29.5%for the non-urban IMpROVE *** alternative method is examined for Brc and black carbon(Bc)adjustments by calculating the AbsorptionÅngström Exponent(AAE)for Bc(i.e.,AAE_(Bc))based on the ratios of 635 nm/780 nm light attenuation rather than assuming AAE_(Bc)of *** paired-wavelength calculations result in a median AAE_(Bc)of 0.76 for cSN and 0.8 for IMpROVE,with the majority of samples(i.e.,91%of cSN and 70%of IMpROVE)showing AAE_(Bc)contributions from Brc to AAE at longer wavelengths,the amount of light attenuation at shorter wavelengths(e.g.,405 nm)where Brc is dominant can be *** paired-wavelength method applied to the filter loading adjusted data has a greater effect on urban(fresh)than on non-urban(aged)aerosols,resulting in a factor of two increase in annual averaged Brc light attenuation(from 10.7%to 21.6%)for cSN and by a factor of 1.11(from 29.5%to 32.7%)for IMpROVE *** result demonstrates the importance of particle loading and AAE correction on quantifying Brc light attenuatio

关键词： Organic carbon Brown carbon Elemental carbon Black carbon AbsorptionÅngström Exponent

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Incidence of sports-related sternoclavicular joint dislocations in the United States over the last two decades

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World Journal of Orthopedics 2023年第6期14卷 427-435页

作者： Alexis B Sandler Michael D Baird john p Scanaliato Ayden LW Harris Sorana Raiciulescu clare K Green john c Dunn Nata parnes Department of Orthopaedic Surgery Texas Tech University Health Sciences Center El PasoEl PasoTX 79905United States Department of Orthopaedic Surgery Walter Reed National Military Medical CenterBethesdaMD 20307United States Department of preventive Medicine and Biostatistics Uniformed Services UniversityBethesdaMD 20307United States School of Medicine and Health Sciences The George Washington UniversityWashingtonDC 20001United States Department of Orthopaedic Surgery Carthage Area HospitalCarthageNY 13619United States Department of Orthopaedic Surgery Claxton-Hepburn Medical CenterOgdensburgNY 13669United States

BAcKGROUND Epidemiological understanding of acute sternoclavicular(Sc)dislocations secondary to sports across the United States is poorly *** To identify and assess epidemiological trends of Sc dislocations occurring secondary to sports-related mechanisms across United States over the past two *** This cross-sectional,descriptive epidemiological study evaluates epidemiological trends of Sc dislocations from sports that present to emergency departments(EDs)across the United *** were obtained from the National Electronic Injury Surveillance System database spanning two *** on incidence,patient demographics,mechanisms of injury,dislocation types,incident locales,and patient dispositions were *** 1622 Sc dislocations occurred nationwide from 2001 to 2020[incidence=0.262/1000000 people,confidence interval(cI)=0.250-0.275],comprising 0.1%of shoulder/upper trunk *** patients were male(91%,n=1480)and aged 5-17(61%,n=982).Football,wrestling,and biking were the most frequently implicated sports,with contact sports responsible for 59%of athletic injuries(n=961).Recreational vehicle-related sports injuries,such as all-terrain vehicles,dirt bikes,and mopeds accounted for 7.8%of all injuries(n=126),with dirt bikes specifically comprising 3.7%(n=61).Ultimately,82%were discharged from the ED(n=1337),12%were admitted(n=194),and 6%were transferred(n=90).All recorded posterior dislocations were admitted or transferred from the *** sustaining Sc dislocations from contact sports had a significantly increased risk of hospital admission or transfer rather than discharge from the ED as compared to patients whose injuries were from non-contact sports(incidence rate ratio=1.46,cI:=1.32-1.61,pcONcLUSION Sc dislocations from sports continue to be rare with a stably low incidence over the past two decades,likely comprising a smaller proportion of shoulder dislocations than previously *** sports are a fr

关键词： Sternoclavicular dislocation Sternoclavicular joint Epidemiology Football contact sports

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New clues that May Link Osteoporosis to the circulating Lipid profile

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Bone Research 2013年第3期1卷 260-266页

作者： catalina poiana Valentin Radoi Mara carsote john p. Bilezikian "c. I. parhon" National Institute of Endocrinology Bucharest Bucharest Romania University of Medicine and pharmacy"carol Davila" Bucharest Bucharest Romania college of physicians and Surgeons Columbia UniversityNew York NY USA

Bone Mineral Density （BMD） is a gold standard for the diagnosis of osteoporosis and is also important in the assessment of fracture risk. Other risk factors have been identified that together make up fracture risk assessment tools such as FRAX. Another potential factor, circulating lipids, has been suggested because of reports linking statins to fracture risk reduction. We analyzed the lipid profile in a cohort of women diagnosed with postmenopausal osteoporosis based on bone density determination： 610 women with osteo- porosis （mean lumbar spine T-score -3.16±0.81, mean yrs. since menopause 15.79±8.9） were grouped according to age at evaluation （〈 50 years, 51-60 years, 61-70 years, 〉 70 years）, the presence/absence of a history of a fragility fracture, statin and/or antiresorptive drug use. There was no correlation between BMD and Body Mass Index （BMI： p〉0.05, r2〈0.02）. However, when BMD was correlated with both BMI and the lipid profile （Triglycerides, cholesterol, LDLc, HDLc）, significant correlations were found in 5 cohorts： 51-60 years with fractures （n=61, r2=0.14, p〈0.01）, 61-70 years （n=201, r2=0.09, p〈0.01） with fractures （n=88, r2=0.14, p〈0.01） or without fractures （n=113, r2=0.24, p=0.02） and over 70 years （n=247, r2=0.11, p〈0.01）.

关键词： osteoporosis bone mineral density lipid cholesterol triglycerides HDL-cholesterol

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Metabolomic.p.ofiling in Selaginella lepidophylla at Various Hydration States provides New Insights into the Mechanistic Basis of Desiccation Tolerance

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Molecular plant 2013年第2期6卷 369-385页

作者： Abou Yobi Bernard W.M. Wone Wenxin Xu Danny c. Alexander Lining Guo john A. Ryals Melvin J. Oliver john c. cushman Department of Biochemistry and Molecular Biology University of Nevada Reno NV 89557-0330 USA Department of Biological Sciences University of Nevada Reno NV 89557-0314 USA Metabolon Inc. 800 Capitola Drive Suite 1 Durham NC 27713 USA US Department of Agriculture-Agricultural Research Service Plant Genetic Research Unit University of Missouri Columbia MI 65211 USA

Selaginella lepidophylla is one of only a few species of spike mosses （Selaginellaceae） that have evolved des-iccation tolerance （DT） or the ability to ＇resurrect＇ from an air-dried state. In order to understand the metabolic basis of DT, S, lepidophylla was subjected to a five-stage, rehydration/dehydration cycle, then analyzed using non-biased, global metabolomics profiling technology based on Gc/MS and UHLc/MS/MS2 platforms. A total of 251 metabolites including 167 named （66.5%） and 84 （33.4%） unnamed compounds were characterized. Only 42 （16.7%） and 74 （29.5%） of compounds showed significantly increased or decreased abundance, respectively, indicating that most compounds were produced con-stitutively, including highly abundant trehalose, sucrose, and glucose. Several glycolysis/gluconeogenesis and tricarboxylic acid （TcA） cycle intermediates showed increased abundance at 100% relative water content （RWc） and 50% RWc. Vanillate, a potent antioxidant, was also more abundant in the hydrated state. Many different sugar alcohols and sugar acids were more abundant in the hydrated state. These polyols likely decelerate the rate of water loss during the drying process as well as slow water absorption during rehydration, stabilize proteins, and scavenge reactive oxygen species （ROS）. In contrast, nitrogen-rich and y-glutamyl amino acids, citrulline, and nucleotide catabolism products （e.g. allantoin） were more abundant in the dry states, suggesting that these compounds might play important roles in nitrogen remobilization during rehydration or in ROS scavenging. UV-protective compounds such as 3-（3-hydroxyphenyl）propionate, apigenin, and naringenin, were more abundant in the dry states. Most lipids were produced constitutively, with the exc.p.ion of choline phosphate, which was more abundant in dry states and likely plays a role in membrane hydration and stabilization. In contrast, several poly- unsaturated fatty acids were more abundant in the hydrated states, suggestin

关键词： abiotic/environmental stress mass spectrometry metabolomics oxidative/photooxidative stress desiccationtolerance Selaginella.

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Effect of adding a smart potassium ion-responsive c.p.lymer into polysulfone support membrane on the performance of thin-film composite nanofiltration membrane

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Frontiers of chemical Science and Engineering 2019年第2期13卷 400-414页

作者： Meibo He Zhuang Liu Tong Li chen chen Baicang Liu john c.crittenden Institute of New Energy and Low-carbon Technology Sichuan UniversityChengdu 610207China college of Architecture and Environment Sichuan UniversityChengdu 610065China School of chemical Engineering Sichuan UniversityChengdu 610065China Research center for Eco-Environmental Sciences Chinese Academy of SciencesBeijing 100085China Litree purifying Technology co. LtdHaikou 571126China Brook Byers Institute for Sustainable Systems School of Civil and Environmental EngineeringGeorgia Institute of TechnologyAtlantaGA 30332USA

Thin-film composite (TFc) nanofiltration (NF) membranes were fabricated via the interfacial polymerization of piperazine (pIp) and 1,3,5-benzenetricart)oiiyl trichloride on polysulfone (pSf) support membranes blended with K^+-responsive poly(N-isopropylacryamideco- acryloylamidobenzo-15-crown-5)(p(NIpAM-co- AAB15c5)). Membranes were characterized by attenuated total reflection Fourier transform infrared spectrosc.p., X-ray photoelectron spectrosc.p., atomic force microsc.p., scanning electron microsc.p., contact angle, and filtration tests. The results showed that:(1) Under K^+-free conditions, the blended p(NIpAM-co-AAB15c5)/pSf supports had porous and hydrophilic surfaces, thereby producing NF membranes with smooth surfaces and low MgSO4 rejections;(2) With K^+ in the pIp solution, the surface roughness and water permeability of the resultant NF membrane were increased due to the K^+-induced transition of low-content p(NIpAM-co-AAB15c5) from hydrophilic to hydrophobic;(3) After a curing treatment at 95℃, the improved NF membrane achieved an even higher pure water permeability of 10.97 L·m^-2·h^-1 - bar1 under 200 psi. Overall, this study provides a novel method to improve the performance of NF membranes and helps understand the influence of supports on TFc membranes.

关键词： nanofiltration interfacial polymerization support membrane potassium ion-responsive thin-film composite

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chemical poison and regeneration of ScR catalysts for NOx removal from stationary sources

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Frontiers of Environmental Science & Engineering 2016年第3期10卷 413-427页

作者： Junhua LI Yue pENG Huazhen cHANG Xiang LI john c. cRITTENDEN Jiming HAO State Key Joint Laboratory of Environment Simulation and pollution control School of Environment Tsinghua University Beijing 100084 China School of civil and Environmental Engineering and the Brook Byers Institute for Sustainable Systems Georgia Institute of Technology 800 West Peachtree Street Suite 400 F-H Atlanta GA 30332-0595 United States School of Environment and Natural Resource Renmin University of China Beijing 100872 China

Selective catalytic reduction （ScR） of NOx with NH3 is an effective technique to remove NOx from stationary sources, such as coal-fired power plant and industrial boilers. Some of elements in the fly ash deactivate the catalyst due to strong chemisorptions on the active sites. The poisons may act by simply blocking active sites or alter the adsorption behaviors of reactants and products by an electronic interaction. This review is mainly focused on the chemical poisoning on V2O5-based catalysts, environmental-benign catalysts and low temperature catalysts. Several common poisons including alkali/alkaline earth metals, SO2 and heavy metals etc. are referred and their poisoning mechanisms on catalysts are discussed. The regeneration methods of poisoned catalysts and the development of poison-resistance catalysts are also compared and analyzed. Finally, future research directions in developing poisoning resistance catalysts and facile efficient regeneration methods for ScR catalysts are proposed.

关键词： flue gas DeNOx ScR catalyst poison and regeneration

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XFEL data analysis for structural biology

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Frontiers of Electrical and Electronic Engineering in china 2016年第3期4卷 159-176页

作者： Haiguang Liu john c. H. Spence complex Systems Division Beiiin.q Computational Science Research Center Beijing 100193 China physics Department Arizona State University Tempe AZ 85287 USA

X-ray Free Electron Lasers （XFELs） have advanced research in structure biology, by exploiting their ultra-short and bright X-ray pulses. The resulting ＂diffraction before destruction＂ experimental approach allows data collection to outrun radiation damage, a crucial factor that has often limited resolution in the structure determination of biological molecules. Since the first hard X-ray laser （the Linac coherent Light Source （LcLS） at SLAc） commenced operation in 2009, serial femtosecond crystallography （SFX） has rapidly matured into a method for the structural analysis of nano- and micro-crystals. At the same time, single particle structure determination by coherent diffractive imaging, with one particle （such as a virus） per shot, has been under intense development. In this review we describe these applications of X-ray lasers in structural biology, with a focus particularly on aspects of data analysis for the computational research community. We summarize the key problems in data analysis and model reconstruction, and provide perspectives on future research using computational methods.

关键词： X-my Free Electron Laser single particle scattering serial crystallography phase retrieval orientationrecovery

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Seasonal variations and sources of mass and chemical composition for pM_(10) aerosol in Hangzhou,china

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particuology 2009年第3期7卷 161-168页

作者： Junji cao Zhenxing Shen Judith c. chow Guowei Qi john G. Watson State Key Lab of Loess and Quaternary Geology - SKLLQG. Institute of Earth Environment ChineseAcademy of Sciences Xi'an. Shaanxi 710075 China Department of Environmental Science and Engineering. xi'an Jiaotong University. Xi'an 710049. china Division of Atmospheric Sciences. Desert Research Institute. Reno. USA Hangzhou Munic.p.l Environmental Monitoring center Hangzhou 310007 China

Aerosol observation was conducted for four seasons from September 2001 to August 2002 at five sampling sites in Hangzhou, South china, on pM10 mass, 22 elements （Na, Mg, AI, Si, p, S, K, ca, Ti, V, cr, Mn, Fe, Ni, cu, Zn, As. Se, Br, cd, Ba, and pb）, 5 major ions （F^-, cl^ , NO3^-, SO4^2- , and NH4^＋）, and organic and elemental carbon （Oc and Ec）, showing that pM10 mass ranged from 46.7 to 270.8 μg/m^3, with an annual average of 119.2 μg/m^3. Na, AI, Si, S, K, ca, and Fe were the most abundant elements in pM10, most of S being in the form of SO4^2- . SO4^2-, NO3^-, and NH4^＋ were the major ions, which contributed to about 20% of the pM10 mass. The mean seasonal concentrations for SO4^2- , averaged over all sites, were found to be 18.0, 18.5, 24,Z and 21.4 μg/m^3, for spring, summer, autumn, and winter, respectively, while the corresponding loadings for NO3^- were 7.2, 4.7, 7.1, and 11.2 μg/m^3, and for NH4^＋ were 6.0, 5.9, 8.2, and 9.3 μg/m^3, in the form mostly of NH4NO3 in spring, autumn, and winter, and mostly of （NH4）2SO4 in summer. The low NO3^-/SO4^2- ratio found indicates coal combustion as the major source throughout the year. The mean annual concentrations of Oc and Ec in pM10 were found to be 21.4, and 4.1 μg/m^3, respectively. Material balance calculation indicated that fugitive dust, the secondary aerosol, and carbonaceous matter were the most abundant species in pM10 for the four seasons, as is characteristic for cities in South china.

关键词： pM10 Elements lons carbon Material balance

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A cAScADIc MULTIGRID ALGORITHM FOR cOMpUTING THE FIEDLER VEcTOR OF GRApH LApLAcIANS

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Journal of computational Mathematics 2015年第2期33卷 209-226页

作者： john c. Urschel Jinchao Xu Xiaozhe Hu Ludmil T. Zikatanov Department of Mathematics Penn State University Pennsylvania USA Department of Mathematics Tufts University Medford MA 02155 Department of Mathematics Penn State University Pennsylvania USA Institute of Mathematics and Informatics Bulgarian Academy of Sciences Sofia Bulgaria

In this paper, we develop a cascadic multigrid algorithm for fast computation of the Fiedler vector of a graph Laplacian, namely, the eigenvector corresponding to the second smallest eigenvalne. This vector has been found to have applications in fields such as graph partitioning and graph drawing. The algorithm is a purely algebraic approach based on a heavy edge coarsening scheme and pointwise smoothing for refinement. To gain theoretical insight, we also consider the related cascadic multigrid method in the geometric setting for elliptic eigenvalue problems and show its uniform convergence under certain assumptions. Numerical tests are presented for computing the Fiedler vector of several practical graphs, and numerical results show the efficiency and optimality of our proposed cascadic multigrid algorithm.

关键词： Graph Laplacian cascadic Multigrid Fiedler vector Elliptic eigenvalue prob-lems.

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chronic exposure to elevated levels of manganese and nickel is not harmful to a cosmopolitan detritivore, Megaselia scalaris （Diptera： phoridae）

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Insect Science 2009年第1期16卷 73-79页

作者： Mary A. Sorensen c. Mae chase-Dunn john T. Trumble Department of Entomology University of California Riverside California 92521 USA

Environmental contamination with metals such as manganese （Mn） and nickel （Ni） often results in elevated concentrations of these metals in plant tissues. At high concentrations, these metals are known to have detrimental effects on certain insect herbivores. Using laboratory bioassays and artificial diet, we investigated the development and survival of a cosmopolitan insect detritivore, Megaselia scalaris （Diptera： phoridae）, exposed to concentrations of Mn and Ni reaching 2 600 mg Mn/kg and 5 200 mg Ni/kg dry mass （dm） in artificial diet. Surprisingly, Ni and Mn at the concentrations tested did not harm this fly. Treatment groups from diets with 260-2 600 mg Mn/kg dm and 1 300-5 200 mg Ni/kg dm had significantly shorter larval development times, overall times to adult emergence, and both pupariation and pupal eclosion times compared to a control group. Wing length of females, a correlate of adult fitness, was also greater in metal treatment groups. Other measures including rate of egg hatch, percentage of emerging flies that were female, and wing length of male flies, were not significantly different in metal treatment groups. We conclude that Megaselia scalaris is tolerant of exc.p.ionally high levels of Mn and Ni.

关键词： detritivore elemental defense heavy metal hyperaccumulator pollution

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