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24篇 您的检索式:作者名="M.Allen"
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1藏东玉龙超大型斑岩铜矿床成岩成矿系统时间跨度分析显示文摘藏东玉龙超大型斑岩铜矿床是目前西藏发现的最大斑岩铜矿床,含铜岩体主要由早期石英二长斑岩及晚期正长花岗斑岩组成。本文用LA-ICP-MS法测定早期石英二长斑岩及晚期正长花岗斑岩锆石U-Pb年龄及Ar-Ar法测定钾质蚀变带黑云母的Ar-Ar年龄,发现玉龙含矿斑岩体早期石英二长斑岩锆石LA-ICP-MS U-Pb年龄(41.3±0.3Ma,MSWD=0.92)与晚期正长花岗斑岩锆石LA-ICP-MS U-Pb年龄(41.3±0.2Ma,MSWD=1.24)基本相同,也和黑云母Ar-Ar坪年龄(41.7±0.8Ma)及等时线年龄(41.3±0.8Ma)在误差范围内一致。玉龙斑岩铜矿早期及晚期岩体锆石U-Pb年龄一致表明含矿岩体在地质上的早期及晚期主要是岩浆在较短时间内脉动侵入所致。玉龙含矿岩体锆石U-pb年龄(封闭温度约800℃)、^(39)Ar-^(40)Ar年龄(封闭温度约300℃)及前人获得的Re-0s年龄40.1±1.8Ma(封闭温度约500℃)在误差范围内基本一致,表明含矿岩体岩体快速冷却,玉龙超大型斑岩铜矿床成岩成矿系统时间跨度小于1Ma。梁华英 莫济海 孙卫东 喻亨祥 张玉泉 Charllote M.ALLEN 2008岩石学报2008,24,10:32
2Showering in Flint, MI: Is there a DBP problem?显示文摘Lead contamination in the City of Flint, MI has been well documented over the past two years, with lead levels above the EPA Action Level until summer 2016. This resulted from an ill-fated decision to switch from Detroit water(Lake Huron) with corrosion control, to Flint River water without corrosion control. Although lead levels are now closer to normal,reports of skin rashes have sparked questions surrounding tap water in some Flint homes.This study investigated the presence of contaminants, including disinfection by-products(DBPs), in the hot tap water used for showering in the homes of residents in Flint. Extensive quantitative analysis of 61 regulated and priority unregulated DBPs was conducted in Flint hot and cold tap water, along with the analysis of 50 volatile organic compounds and a nontarget comprehensive, broadscreen analysis, to identify a possible source for the reported skin rashes. For comparison, chlorinated hot and cold waters from three other cities were also sampled, including Detroit, which also uses Lake Huron as its source water.Results showed that hot water samples generally contained elevated levels of regulated and priority unregulated DBPs compared to cold water samples, but trihalomethanes were still within regulatory limits. Overall, hot shower water from Flint was similar to waters sampled from the three other cities and did not have unusually high levels of DBPs or other organic chemicals that could be responsible for the skin rashes observed by residents. It is possible that an inorganic chemical or microbial contaminant may be responsible.Joshua M.Allen Amy A.Cuthbertson Hannah K.Liberatore Susana Y.Kimura Anurag Mantha Marc A.Edwards Susan D.Richardson 2017Journal of Environmental Sciences2017,29,8:5
3Apparent redox potential discontinuity(aRPD) depth as a relative measure of sediment oxygen content and habitat quality显示文摘As hypoxic conditions spread in our oceans,indices that quickly and efficiently assess oxygen content in sediment pore water,and habitat quality are increasingly becoming desirable.Depth to the apparent redox potential discontinuity(aRPD) in sediment is one such index;however,the relationship between aRPD depth and oxygen content is still unclear.We quantified oxygen content in sediment pore water with a dissolved oxygen(DO) probe,utilizing luminescent technology,to determine how DO concentration varies with depth in the sediment,and with position relative to the aRPD(above versus below) on an intertidal mudflat in the Bay of Fundy,Canada.Based on generalized linear regression models,we found that depth in the sediment was a poor predictor of pore water DO concentration,while position in the sediment relative to the aRPD was a good predictor.Further,sediment above the aRPD had higher DO content than sediment below.We maintain that aRPD depth is a good measure of relative oxygen content in sediment pore water,as well as habitat quality.However,we recommend caution as the factors that influence aRPD depth arc numerous and variable;therefore,the relationship between aRPD depth and DO content should be experimentally confirmed in any system of interest before aRPD depth is used as an indicator.Travis G.GERWING Alyssa M.ALLEN GERWING Diana J.HAMILTON Myriam A.BARBEAU 2015International Journal of Sediment Research2015,30,1:3
4Total organic halogen(TOX) in human urine: A halogen-specific method for human exposure studies显示文摘Disinfection by-products(DBPs) are a complex mixture of compounds unintentionally formed as a result of disinfection processes used to treat drinking water. Effects of long-term exposure to DBPs are mostly unknown and were the subject of recent epidemiological studies. However,most bioanalytical methods focus on a select few DBPs. In this study, a new comprehensive bioanalytical method has been developed that can quantify mixtures of organic halogenated compounds, including DBPs, in human urine as total organic chlorine(TOCl), total organic bromine(TOBr), and total organic iodine(TOI). The optimized method consists of urine dilution, adsorption to activated carbon, pyrolysis of activated carbon, absorption of gases in an aqueous solution, and halide analysis with ion chromatography and inductively coupled plasma-mass spectrometry. Spike recoveries for TOCl, TOBr, and TOI measurements ranged between 78% and 99%. Average TOCl, TOBr, and TOI concentrations in five urine samples from volunteers who consumed tap water were 1850, 82, and 21.0 μg/L as X^-, respectively.Volunteers who consumed spring water(control) had TOCl, TOBr, and TOI average concentrations in urine of 1090, 88, and 10.3 μg/L as X^-, respectively. TOCl and TOI in the urine samples from tap water consumers were higher than the control. However, TOBr was slightly lower in tap water urine samples compared to mineral water urine samples, indicating other sources of environmental exposure other than drinking water. A larger sample population that consumes tap water from different cities and mineral water is needed to determine TOCl, TOBr, and TOI exposure from drinking water.Susana Y.Kimura Weiwei Zheng Taylor N.Hipp Joshua M.Allen Susan D.Richardson 2017Journal of Environmental Sciences2017,29,8:3
5Pancreas volumes in humans from birth to age one hundred taking into account sex, obesity, and presence of type‐2 diabetes显示文摘Y.Saisho A.E.Butler J.J.Meier T.Monchamp M.Allen‐Auerbach R.A.Rizza P.C.Butler 2007Clin Anat2007,,8:1
6Pancreas volumes in humans from birth to age one hundred taking into account sex, obesity, and presence of type‐2 diabetes显示文摘Y.Saisho A.E.Butler J.J.Meier T.Monchamp M.Allen‐Auerbach R.A.Rizza P.C.Butler 2007Clin Anat2007,,8:1
7Disturbance increases high tide travel distance of a roosting shorebird but only marginally affects daily energy expenditure显示文摘Background:Anthropogenic disturbance can negatively affect an animal's energy budget by evoking movement responses.Existing research focuses mainly on immediate displacement as a disturbance effect,since this can be easily observed in the field. However, effects on movement over longer timescales are poorly examined and it is largely unknown if and to what extent they reflect immediate responses.Longer-term responses could for example be larger than immediate responses if birds, after disturbance, return to the original location and thereby travel twice the immediate disturbed distance. Methods:We combined GPS tracking data with observational data to quantify the effects of anthropogenic (air force and walkers) and non-anthropogenic disturbances on distances travelled by roosting Eurasian Oystercatchers (Haematopus ostralegus) during the non-breeding season. We compared immediate displacement after a disturbance with distance travelled during the entire high tide period (longer-term response), while accounting for environmental factors.Additionally,we calculated energy expenditure due to disturbance based on observed disturbance frequencies.Results:Disturbance resulted in an immediate displacement response of ~200 m (median).Air force disturbances tended to yield larger immediate responses than walker and,especially,than non-anthropogenic disturbances.Longer-term responses and immediate responses were approximately similar,suggesting that,over longer timescales,spatial disturbance effects in the study area remain confined to immediate effects.However,disturbances were infrequent (0.17 disturbances per bird per hour) and most disturbances were of natural origin (62%).Consequently, anthropogenic disturbance of roosting oystercatchers in the study area on average costs 0.08% of the daily energy expenditure. Conclusions:Our results suggest that immediate spatial responses to disturbance can be a useful proxy for spatial responses over longer timescales.Over the non-exhaustive range of conditions investigated,energetic consequences of spatial disturbance responses for an oystercatcher in the study area are marginal due to low disturbance levels.Hans Linssen Martijn van de Pol Andrew M.Allen Mitzi Jans Bruno J.Ens Karen L.Krijgsveld Magali Frauendorf Henk-Jan van der Kolk 2019Avian Research2019,10,3:1
8Depth to the apparent redox potential discontinuity(aRPD)as a parameter of interest in marine benthic habitat quality models显示文摘The usefulness of the apparent redox potential discontinuity(aRPD) in assessments of marine benthic habitat quality was explored at two intertidal mudflats along the north Pacific coast of Canada. Two transects were established at each intertidal site, with three sediment biogeochemistry cores collected from each transect four times over the summer of 2016. Measurements of the sediment pore water dissolved oxygen(DO) content and redox(Eh) conditions were taken at the surface of the core(measured vertically), as well as at increasing depths(1 cm between readings) into the sediment(measured horizontally through predrilled holes in the biogeochemistry corer). While oxic, anoxic, oxidized, and reduced sediment pore water was observed above and below the aRPD, in general, sediment above the aRPD had higher DO content, and higher Eh values than sediment below the aRPD. Therefore, the aRPD depth can be used as a relative indicator of sediment pore water DO and Eh conditions: sediment with a deeper aRPD depth has more available DO, and the pore water has higher Eh values(more oxidized or less reduced) than sediment with a shallower aRPD depth. As such, the aRPD depth is a useful parameter to include in models that assess the quality of marine benthic habitats.Travis G.Gerwing Kieran Cox Alyssa M.Allen Gerwing Charmaine N.Carr-Harris Sarah E.Dudas Francis Juanes 2018International Journal of Sediment Research2018,33,2:1
9Relationships between regulated DBPs and emerging DBPs of health concern in U.S. drinking water显示文摘A survey was conducted at eight U.S. drinking water plants, that spanned a wide range of water qualities and treatment/disinfection practices. Plants that treated heavily-wastewaterimpacted source waters had lower trihalomethane to dihaloacetonitrile ratios due to the presence of more organic nitrogen and HAN precursors. As the bromide to total organic carbon ratio increased, there was more bromine incorporation into DBPs. This has been shown in other studies for THMs and selected emerging DBPs(HANs), whereas this study examined bromine incorporation for a wider group of emerging DBPs(haloacetaldehydes, halonitromethanes). Moreover, bromine incorporation into the emerging DBPs was, in general, similar to that of the THMs. Epidemiology studies that show an association between adverse health effects and brominated THMs may be due to the formation of brominated emerging DBPs of heath concern. Plants with higher free chlorine contact times before ammonia addition to form chloramines had less iodinated DBP formation in chloraminated distribution systems, where there was more oxidation of the iodide to iodate(a sink for the iodide) by the chlorine. This has been shown in many bench-scale studies(primarily for iodinated THMs), but seldom in full-scale studies(where this study also showed the impact on total organic iodine. Collectively, the THMs, haloacetic acids, and emerging DBPs accounted for a significant portion of the TOCl, TOBr, and TOI;however, ~50% of the TOCl and TOBr is still unknown. The correlation of the sum of detected DBPs with the TOCl and TOBr suggests that they can be used as reliable surrogates.Stuart W.Krasner Ai Jia Chih-Fen T.Lee Raha Shirkhani Joshua M.Allen Susan D.Richardson Michael J.Plewa 2022Journal of Environmental Sciences2022,34,7:1
10Genetically separable determinants of hair keratin gene expression显示文摘MichaelSchorpp ThomasSchlake DarrenKreamalmeyer Paul M.Allen ThomasBoehm 2000Dev Dyn2000,,3:1
11A prospective multicentre study of pharmacist initiated changes to drug therapy and patient management in acute care government funded hospitals显示文摘Michael J.Dooley Karen M.Allen Christopher J.Doecke Kirsten J.Galbraith George R.Taylor JenniferBright Dianne L.Carey 2004British Journal of Clinical Pharmacology2004,,4:1
12Prognostic value of cardiac troponin I elevation after percutaneous coronary intervention in patients with chronic renal insufficiency: A 12‐month outcome analysis显示文摘LuisGruberg ShmuelFuchs RonWaksman Augusto D.Pichard Kenneth M.Kent John R.Laird HongshengWu SayedElsayyad Craig M.Allen Lowell F.Satler 2002Cathet Cardiovasc Intervent2002,,2:1
13Testing the Clausius-Clapeyron constraint on changes in extreme precipitation under CO2 warming显示文摘Pall P M.Allen D.Stone 0,,04:1
14Spatial phylogenetics of the North American flora显示文摘North America is a large continent with extensive climatic,geological,soil,and biological diversity.As biota faces threat from habitat destruction and climate change,making a quantitative assessment of biodiversity becomes critically important.Rapid digitization of plant specimen records and accumulation of DNA sequence data enable a much-needed broad synthesis of species occurrences with phylogenetic data.In this study,the first such synthesis of a flora from such a large and diverse part of the world is attempted,all seed plants from the North American continent(here defined to include Canada,United States,and Mexico),with a focus on examining phylogenetic diversity and endemism.We collected digitized plant specimen records and chose a coarse grain for analysis,recognizing that this grain is currently necessary for reasonable completeness per sampling unit.We found that raw richness and endemism patterns largely support previous hypotheses of biodiversity hotspots.The application of phylogenetic metrics and a randomization test revealed novel results,including a significant phylogenetic clustering across the continent,a striking east-west geographical difference in the distribution of branch lengths,and the discovery of centers of neo-and paleoendemism in Mexico,the southwestern USA,and the southeastern USA.Finally,our examination of phylogenetic beta diversity provides a new approach to compare centers of endemism.We discuss the empirical challenges of working at the continental scale and the need for more sampling across large parts of the continent,for both DNA data for terminal taxa and spatial data for poorly understood regions,to confirm and extend these results.Brent D.Mishler Robert Guralnick Pamela S.Soltis Stephen A.Smith Douglas E.Soltis Narayani Barve Julie M.Allen Shawn W.Laffan 2020Journal of Systematics and Evolution2020,58,4:1
15Transplant Glomerulopathy: Ultrastructural Abnormalities Occur Early in Longitudinal Analysis of Protocol Biopsies显示文摘M. D.Wavamunno P. J.O’Connell M.Vitalone C. L.‐S.Fung R. D. M.Allen J. R.Chapman B. J.Nankivell 2007American Journal of Transplantation2007,,12:1
16Hybridization and polyploidy as drivers of continuing evolution and speciation in Sorbus显示文摘ASHLEYROBERTSON TIMOTHY C. G.RICH ALEXANDRA M.ALLEN LIBBYHOUSTON CATROBERTS JON R.BRIDLE STEPHEN A.HARRIS SIMON J.HISCOCK 2010Molecular Ecology2010,,8:1
17AUTOMATED METHODS FOR ESTIMATING BASEFLOW AND GROUND WATER RECHARGE FROM STREAMFLOW RECORDS显示文摘J. G.Arnold P M.Allen 2007JAWRA Journal of the American Water Resources Association2007,,2:1
18Detrital zircon U-Pb-He double dating: A method of quantifying long- and short-term exhumation rates in collisional orogens显示文摘一个 U-Pb-He 双 dating 方法从 Ganges 河与核心边界结构被用于由岩屑形成的锆石以便为喜马拉雅山脉决定平均短期、长期的发掘率。长期的率从在喜玛拉雅的造山运动和他们的结晶化温度期间形成了的谷物的变形边界的 U/Pb 年龄被计算,它从 Ti-in-zircon 温度计是计算的。短期的率被计算从(U-Th )/He 与适当闭合温度谷物变老。结果表演为喜马拉雅山脉的短期的率,哪个从 0.70 ? 散瑮牥猠牵慦散瀠敲獳牵 ? 湡 ? 慭楸畭 ? 楷摮猠数摥 ? 湡 ? 瑳畲瑣牵 ? 牰摥捩楴湯愠敲漠癢潩獵祬椠灭潲敶 ? 楷桴吠歩?? 嘭牡洠瑥潨 ? 潦 ? 祝栭瀠敲楤瑣潩?Christina Yan WANG Ian H.CAMPBELL Peter W.REINERS Charlotte M.ALLEN 2014Science China Earth Sciences2014,57,11:0
19Colour-ring wear and loss effects in citizen science mark-resighting studies显示文摘Background: Ring wear and loss may have important consequences for mark-recapture studies that aim to estimate survival trends. Our study quantifies the rates of wear and loss from a long-running colour-ringing project of the Eurasian Oystercatcher (Haematopus ostralegus) in the Netherlands. Methods: Our analysis included 8909 colour-ringed oystercatchers with 118,071 resightings, predominantly ringed and observed by citizen scientists. We quantified how ring wear and loss may vary with ring colour and age, and how this may impact resighting probabilities. We then determined how ring loss may impact survival estimates and resighting probabilities of mark-recapture models by simulating four scenarios of how citizen scientists may resight and report birds with lost colour rings. Results: Annual rates of colour ring loss averaged 2.5% compared with 1% for ring wear, but lost rings also had a higher reporting probability (31.2%) than worn rings (10.3%). Lost rings may not directly impact survival estimates since 50% of oystercatchers with lost rings could still be uniquely identified. Ring wear and loss rapidly increased between 10 and 15 years after ringing. Rates of ring loss were comparable amongst ring colours, but the wear rate appeared higher for red and white rings compared to other colours. Rates of ring wear and loss varied significantly amongst different regions in our study, which were characterised as having different habitat features. Differential rates of ring wear may have important implications for studies conducted over large geographical scales or of multiple species. Conclusions: Based on simulations of ring loss in our population, estimates of apparent survival may be 0.3–1.2% lower whilst the impact of ring wear was deemed even lower. We developed a table of recommendations containing advice for ring fitting, data collection, study design, and mark-recapture analyses, so that future colour-ringing studies can benefit from our experiences in collecting and analysing data of ring wear and loss through citizen science.Andrew M.Allen Bruno J.Ens Martijn van de Pol Henk van der Jeugd Magali Frauendorf Henk-Jan van der Kolk Kees Oosterbeek Jeroen Nienhuis Eelke Jongejans 2019Avian Research2019,10,2:0
20基于网络的加利福尼亚地震预警算法设计:ElarmS-2显示文摘加利福尼亚综合地震台网(CISN)正在为加利福尼亚州开发一种地震预警(EEW)示范系统。在加利福尼亚综合地震台网震动警报(ShakeAlert)项目中,正在检验3种算法,其中之一是基于台网的地震警报系统(ElarmS)的地震预警系统。在过去的3年中,ElarmS算法经历了大量重新评定和解决技术与方法的若干挑战。在新的生产级产品,即ElarmS第2版(简称ElarmS-2或E2)中,对算法的改进扩大到适用当前地震台网的布局,改进了硬件和软件的性能,提高了预警处理速度和警报的准确性。E2设计为模块化的代码,由改进关联器的新事件监测模块组成,可以更迅速地与少数触发关联匹配,同时也增加了几个新的警报过滤检查,从而帮助最大限度地减少虚报。本文概述了这个新的在线实时系统的方法,总结了其性能。从2012年10月2日到2013年2月15日的在线操作性能来看,平均而言,在所有加利福尼亚发生的地震事件中,ElarmS系统在初至P波到达后8.68±3.73s发布预警。这一时间在台站仪器密集地区减少了2s。震级和发震时刻的标准差为0.4级和1.2s,定位误差中值为3.8km。在加利福尼亚发生的29次地震(MANSS>3.5)中,E2成功检测到26次,发布了两次虚报。E2现正传送警报给震动警报系统,由震动警报系统发布给测试用户。H.Serdar Kuyuk Richard M.Allen Holly Brown Margaret Hellweg Ivan Henson Douglas Neuhauser 张永刚 郝永梅 杜微 吕春来 2015世界地震译丛2015,46,4:0
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