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History and evaluation of national-scale geochemical data sets for the United States

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Geoscience Frontiers 2013年第2期4卷 167-183页

作者： david B.Smith Steven M.Smith john d.Horton U.S.Geological Survey.denver Federal Center MS 973.DenverCO 80225USA

Six national-scale,or near national-scale,geochemical data sets for soils or stream sediments exist for the United *** earliest of these,here termed the ＇Shacklette＇ data set,was generated by a U.S. Geological Survey（USGS） project conducted from 1961 to *** project used soil collected from a depth of about 20 cm as the sampling medium at 1323 sites throughout the conterminous *** National Uranium Resource Evaluation Hydrogeochemical and Stream Sediment Reconnaissance（NUREHSSR） Program of the *** of Energy was conducted from 1975 to 1984 and collected either stream sediments,lake sediments,or soils at more than 378,000 sites in both the conterminous *** *** sampled area represented about 65%of the *** Natural Resources Conservation Service（NRCS）,from 1978 to 1982,collected samples from multiple soil horizons at sites within the major crop-growing regions of the conterminous *** data set contains analyses of more than 3000 *** National Geochemical Survey,a USGS project conducted from 1997 to 2009,used a subset of the NURE-HSSR archival samples as its starting point and then collected primarily stream sediments, with occasional soils,in the parts of the *** covered by the NURE-HSSR *** data set contains chemical analyses for more than 70,000 *** USGS,in collaboration with the Mexican Geological Survey and the Geological Survey of Canada,initiated soil sampling for the North American Soil Geochemical Landscapes Project in *** of three horizons or depths at more than 4800 sites in the *** completed in 2010,and chemical analyses are currently *** NRCS initiated a project in the 1990s to analyze the various soil horizons from selected pedons throughout the *** data set currently contains data from more than 1400 *** paper（1） discusses each data set in terms of its purpose,sample collection protocols,and analytical methods;and（2） evaluates each data set in terms

关键词： Geochemical mapping National-scale geochemical data Geochemical baselines United States

Predictive modelling of ferroelectric tunnel junctions

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npj Computational Materials 2016年第1期2卷 150-162页

作者： Julian P Velev john d Burton Mikhail Ye Zhuravlev Evgeny Y Tsymbal department of Physics and Astronomy University of NebraskaLincolnNEUSA department of Physics and Astronomy University of Puerto RicoSan JuanPuerto RicoUSA Nebraska Center for Materials and Nanoscience University of NebraskaLincolnNEUSA Kurnakov Institute for General and Inorganic Chemistry Russian Academy of SciencesMoscowRussia Faculty of Liberal Arts and Sciences St Petersburg State UniversitySt PetersburgRussia

Ferroelectric tunnel junctions combine the phenomena of quantum-mechanical tunnelling and switchable spontaneous polarisation of a nanometre-thick ferroelectric film into novel device *** the ferroelectric barrier polarisation direction produces a sizable change in resistance of the junction—a phenomenon known as the tunnelling electroresistance *** a fundamental perspective,ferroelectric tunnel junctions and their version with ferromagnetic electrodes,i.e.,multiferroic tunnel junctions,are testbeds for studying the underlying mechanisms of tunnelling electroresistance as well as the interplay between electric and magnetic degrees of freedom and their effect on *** a practical perspective,ferroelectric tunnel junctions hold promise for disruptive device *** a very short time,they have traversed the path from basic model predictions to prototypes for novel non-volatile ferroelectric random access memories with non-destructive *** remarkable progress is to a large extent driven by a productive cycle of predictive modelling and innovative experimental *** this review article,we outline the development of the ferroelectric tunnel junction concept and the role of theoretical modelling in guiding experimental *** discuss a wide range of physical phenomena that control the functional properties of ferroelectric tunnel junctions and summarise the state-of-the-art achievements in the field.

关键词： ferroelectric tunnel resistance

MR Imaging of Knee Osteoarthritis and Correlation of Findings with Reported Patient Pain

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Journal of Huazhong University of Science and Technology(Medical Sciences) 2010年第2期30卷 248-254页

作者：艾飞余铖张炜 john N Morelli Kacher d 李小明 department of Radiology Tongji HospitalTongji Medical CollegeHuazhong University of Science and Technology department of Radiology Scott & White Clinic and HospitalTexas A&M University Health Science Center department of Radiology Brigham & Women's HospitalHarvard Medical School

Summary： To evaluate lesion detection of MRI in knee joint osteoarthritis in patients with symptoms of pain, the correlation between MRI findings and varying degrees of reported pain was assessed. Twenty-eight patients （31 knees） with osteoarthritis were recruited for this study. The degree of knee pain was assessed by VRS scores. The knees were evaluated by plain film radiograph utilizing Kellgren-Lawrence scores. Multiple MR sequences were performed on a 1.5T MR-system, including sagittal and coronal dual fast spin echo （TRITE 3660/11/120 ms, slice thickness 5 mm）, coronal spin echo T1-weighted （TR/TE 360/9 ms, slice thickness 5 mm）, sagittal fat saturated 3d-spoiled gradient-recalled echo （TR/TE 50/6 ms; slice thickness 1.5 mm; flip angle 40°）, and 3d steady-state free precession （TR/TE 6/2.2 ms; slice thickness 1.6 mm; flip angle 30°） pulse sequences for the purpose of detecting abnormities of cartilage, menisci, the anterior cruciate ligaments, bone marrow edema-like lesions, osteophytes, synovitis, and joint effusions. MR findings were compared with the degree of pain using Fisher exact test with P values less than 0.05 indicating a statistically significant difference. The results showed that, of the 31 knees evaluated, mild pain was reported in 11 and severe pain in the remainder. Kellgren-Lawrence scores of all 31 evaluated OA knees were as follows： grade 1 lesions （n=6）, grade 2 lesions （n=14）, grade 3 lesions （n=8）, and grade 4 lesions （n=3）. Articular cartilaginous defects were found in 37.1% of knees. Abnormalities of the menisci and anterior cruciate ligaments, bone marrow edema-like lesions, osteophytes, synovitis, and joint effusions were detected in 32.3%, 38.7%, 45.2%, 100%, 15.1% and 67.7% of knees, respectively. Of these variables, only the differences in prevalence of joint effusions were significantly different in the mild and severe pain groups （P=0.004）. It is concluded that MRI evaluates the entire joint structure of the osteoarthritic knee,

关键词： knee osteoarthritis magnetic resonance imaging pain

Effect of Explicit Water Molecules on the Color-Tuning Mechanism of the Firefly

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Chinese Journal of Chemistry 2011年第11期29卷 2301-2307页

作者：闵春刚邹陆一孙颖郭景富任爱民 Goddard, john d State Key Laboratory of Theoretical and Computational Chemistry Institute of Theoretical Chemistry Jilin University Changchun Jilin 130023 China School of Physics Northeast Normal University Changchun Jilin 130024 China department of Chemistry University of Guelph Guelph Ontario Canada NIG 2 W1

The contributions of explicit water molecules to color-tuning mechanism of firefly were studied. The explicit water molecules cause two different structures in the geometrical parameters of keto（-1） both in vacuo and aqueous solution. There are somewhat larger influences on absorption and emission spectra. When water molecules were added only on the side of benzothiazole ring, the spectra shift to the blue. In contrast, when waters were added only on the side of the thiazoline ring, the spectra shift to red. In a word, the color modulation of the emitted light depends on charge redistribution of molecule keto（-1）, mainly the charge change of the benzothiazole and thiazole tings at the two terminal in keto（-1）.

关键词： explicit water molecules firefly bioluminescence density functional theory absorption and emission spectra

Erratum to:Carbonatites and Alkaline Igneous Rocks in Post-Collisional Settings:Storehouses of Rare Earth Elements

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Journal of Earth Science 2022年第4期33卷 1059-1059页

作者： Kathryn M.Goodenough Eimear A.deady Charles d.beard Sam Broom-Fendley Holly A.L.Eliott Frederick van den Berg Husey in Oztirk British Geological Survey the lyell CentreEdinbungh EHI44APUK Instut des Sciences de la Terre Universite Grenoble Alpes38610 GieresFrance Camborme School of Mines Universiy of ExererPenryn CampusPenryn TRI09FEUK School of Environmental Sciences University of DerbyDerbyUK depurtment of Geological Engineering Istanbul Uiniversity-CerrahpasaAvclar Campus34320 Avclar IstanbulTurtkey

This article was orignally published ectronically on the publisher's internet portal on 23 August *** the author(s)'deeision,the copyright of the article changed on 27 of January 2022 to◎Brtish Geological Survey,UKRI 2022 and the article is forthwith distributed under a Creative Commons Attribution 4.0 International License,which permits use,sharing,adaptation,distri-bution and reproduction in any medium or format,as long as you give appropriate credit to the original author(s)and the source,provide a link to the Creative Commons lcece,and indicate if changes were made.

关键词： Earth source Rare

Using doubly-Labeled Water to Measure Energy Expenditure in an Important Small Ectotherm drosophila melanogaster

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Journal of Genetics and Genomics 2014年第9期41卷 505-512页

作者： Matthew d.W.Piper Colin Selman john R.Speakman Linda Partridge Institute of Healthy Ageing Department of GeneticsEvolution and EnvironmentUniversity College LondonGower StreetLondonWCIE 6BTUK Institute of Biodiversity Animal Health and Comparative Medicine University of Glasgow Institute of Biological and Environmental Sciences University of Aberdeen State Key Laboratory of Molecular developmental Biology Institute of Genetics and Developmental BiologyChinese Academy of Sciences

Energy expenditure is a key variable in the study of ageing, and the fruit fly drosophila melanogaster is a model organism that has been used to make step changes in our understanding of the ageing process. Standard methods for measurement of energy expenditure involve placing individuals in metabolic chambers where their oxygen consumption and CO2 production can be quantified. These measurements require separating individuals from any social context, and may only poorly reflect the environment in which the animals normally live. The doubly-labeled water （dLW） method is an isotope-based technique for measuring energy expenditure which overcomes these problems. However, technical challenges mean that the smallest animals this method has been previously applied to weighed 50-200 mg. We overcame these technical challenges to measure energy demands in drosophila weighing 0.78 mg. Mass-specific energy expenditure varied between 43 and 65 mW·g^-1. These estimates are considerably higher than estimates using indirect calorimetry of drosophila in small metabolic chambers （around 18 mW·g^-1）. The methodology we have established extends downwards by three orders of magnitude the size of animals that can be measured using dLW. This approach may be of considerable value in future ageing research attempting to understand the genetic and genomic basis of ageing.

关键词： doubly-labeled water Respiration rate Effect of mating status and sex drosophila

Summer egg diapause in a matchstick grasshopper synchronizes the life cycle and buffers thermal extremes

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Integrative Zoology 2018年第4期13卷 437-449页

作者： Michael R.KEARNEY john dEUTSCHER Jacinta d.KONG Ary A.HOFFMANN School of BioSciences The University of MelbourneParkvilleAustralia

The phenological response is among the most important traits affecting a species’sensitivity to *** insects,strongly seasonal environments often select for a univoltine life cycle such that one seasonal extreme is avoided as an inactive *** understanding the underlying mechanisms for univoltinism,and the consequences of its failure,we can better predict insect responses to climate *** we combine empirical data and simulation studies to investigate the consequences of an unusual diapause mechanism in a parthenogenetic matchstick grasshopper,Warramaba virgo,from arid southern *** field body temperature measurements indicate that this species is a thermoconformer and our laboratory studies of the thermal response of feeding rate imply strong constraints on winter ***,the species exhibits no obligate winter diapause,and eggs can develop in 1 month under constant temperatures approximating the mean soil temperature at the time of oviposition(summer).We show that diurnal temperature cycles exceeding a peak of 36℃ inhibit egg development in summer,and that this is sufficient to prevent autumnal hatching of *** is also strongly retarded below 24℃.Microclimate-driven simulation studies of egg development show that these thermal responses provide robust maintenance of a univoltine life cycle,thereby resulting in survival of heat stress as an egg(due to limited developmental state)and avoidance of cold stress as a nymph and adult(due to overwintering in the soil as an egg).

关键词： egg diapause life cycle matchstick grasshopper phenology thermal extremes thermoregulation

Three-dimensional impact kinetics with foot-strike manipulations during running

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Journal of Sport and Health Science 2017年第4期6卷 489-497页

作者： Andrew d. Nordin Janet S. dufek john A. Mercer department of Kinesiology and Nutrition Sciences University of Nevada Las Vegas NV 89154 USA

Background: Lack of an observable vertical impact peak in fore/mid-foot running has been suggested as a means of reducing lower extremity impact forces, although it is unclear if impact characteristics exist in other axes. The purpose of the investigation was to compare three-dimensional(3 d) impact kinetics among foot-strike conditions in over-ground running using instantaneous loading rate–time ***: Impact characteristics were assessed by identifying peak loading rates in each direction(medial–lateral(ML), anterior–posterior(AP),vertical, and 3 d resultant) following foot-strike instructions(fore-foot, mid-foot, subtle heel, and obvious heel strike). Kinematic and kinetic data were analyzed among 9 male participants in each foot-strike ***: Loading rate peaks were observed in each direction and foot-strike condition, differing in magnitude by direction(3 d resultant and vertical > AP > ML, p ≤ 0.031) and foot-strike: ML(fore-foot and mid-foot strike > obvious heel strike, p ≤ 0.032), AP(fore-foot and mid-foot strikes > subtle-heel and obvious heel strikes, p ≤ 0.023). In each direction, the first loading rate peak occurred later during heel strike running relative to fore-foot(p ≤ 0.019), with vertical and 3 d resultant impact durations exceeding shear(ML and AP, p ≤ 0.007) in each ***: Loading rate–time assessment identified contrasting impact characteristics in each direction and the 3 d resultant following foot-strike manipulations, with potential implications for lower extremity structures in running.

关键词： Fore-foot Heel strike Loading rate Mid-foot Overground Resultant

Etiology,diagnosis, management and outcomes of epiphora referrals to an oculoplastic practice

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International Journal of Ophthalmology(English edition) 2016年第12期9卷 1751-1755页

作者： Guang-Lin Shen john d.Ng Xiao-Ping Ma department of Ophthalmology Zhongshan Hospital of Fudan University Casey Eye Institute Oregon Health and Science University

AIM： To investigate the etiology, diagnosis, management and outcome of epiphora referrals to an oculoplastic ***： Retrospective chart review of patients referred for epiphora to an oculoplastic clinic between 2005 and 2009. Patient demographics, past history, ophthalmic examination, treatment and outcome were ***： There were 237 subjects with a primary complaint of epiphora. They included 130 （55%） females and 107 （45%） males with an average age of 55.9±25.9y. The most common cause of epiphora was lacrimal obstruction （46%）; followed by multifactorial epiphora （22%）, reflex tearing （22%） and eyelid malposition （11%）. differences in prevalence of etiology were noted in terms of age and gender distribution. Of the 182 （77%） patients who returned for follow up, 41 （23%） reported a complete resolution and 102 （56%） reported a significant improvement in their ***： Epiphora is a common condition with many causes. A thorough history and examination are required to provide the appropriate treatment tailored to the underlying cause.

关键词： epiphora etiology lacrimal disease dry eye