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Correlation between plasmid DNA damage induced by PM_(10) and trace metals in inhalable particulate matters in Beijing air

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Science China Earth Sciences 2006年第12期49卷 1323-1331页

作者： T. P. jones l. Merolla R. J. Richard Department of Earth Ocean and Planetary Sciences Cardiff UniversityCardiff CF10 3YE UK School of Biosciences Cardiff University PO Box 911 Cardiff CF10 3US UK

Based on the study of Beijing PM10 bioreactivity with the newly developed plasmid DNA assay method, and analysis for trace elements of PM10, the cause of plasmid DNA damage by PM10 was investigated. The study showed that plasmid DNA oxidative damages by PM10 are of difference in different seasons at various areas. The concentrations of TM50 of PM10 in whole samples respectively collected at urban and comparison sites during winter were 900 μg ml?1 and 74 μg ml?1, while those in their corresponding soluble fractions were 540 μg ml?1 and 86 μg ml?1. In contrast, TM50 contents of PM10 from summer whole samples at urban areas and comparison sites were 116 μg ml?1 and 210 μg ml?1, whereas those in their soluble fractions were 180 μg ml?1 and 306 μg ml?1. The difference of bioreactivity of Beijing PM10 resulted from the variation of trace elements. The oxidative damage of plasmid DNA caused by Pb, Zn, As in PM10 (whole sample) was relatively strong. TM50 and Mn, V, Zn display stronger correlation in the soluble fraction. It implies that Zn could be the major trace element in Beijing PM10 which contributes to oxidative damage to plasmid DNA.

关键词： Beijing PM10 trace metals correlation health effect.

Antibiotic prophylaxis in variceal hemorrhage:Timing,effectiveness and Clostridium difficile rates

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World Journal of Gastroenterology 2010年第42期16卷 5317-5323页

作者： Matthew Rl Brown Graeme jones Kathryn l Nash Mark Wright Indra Neil Guha National Institute for Health Research Nottingham Digestive Diseases Centre Biomedical Research Unit Nottingham University Hospitals NHS TrustE Level West BlockQueens Medical Centre CampusDerby RoadNottinghamNG7 2UHUnited kingdom Department of Microbiology Southampton University Hospital TrustLevel BSouthampton General HospitalSouthamptonS016 6YDUnited Kingdom liver Unit Southampton University Hospital TrustLevel FSouthampton General HospitalSouthamptonSO16 6YDUnited Kingdom

AIM:To investigate if antibiotics administered within 8 h of endoscopy reduce mortality or increase the incidence of Clostridium difficile infection(CDI).METHODS:A 2-year retrospective analysis of all patients who presented with first variceal hemorrhage was *** primary outcome measure was 28-d *** outcome measures were 28-d rebleeding rates and 28-d incidence of *** patients were admitted to a tertiary liver unit with a consultantled,24-h endoscopy *** received standard care including terlipressin *** collection included:primary and secondary outcome measures,timing of first administration of intravenous antibiotics,eti-ology of liver disease,demographics,endoscopy details and complications.A prospective study was undertaken to determine the incidence of CDI in the study population and general medical inpatients admitted for antibiotic therapy of at least 5 d *** analysis was undertaken using univariate,non-parametric tests and multivariate logistic regression ***:There were 70 first presentations of variceal hemorrhage during the study *** percent of cases were male and 65.7% were due to chronic alcoholic liver *** total,64/70(91.4%) patients received antibiotics as prophylaxis during their ***,53/70(75.7%) received antibiotics either before endoscopy or within 8 h of endoscopy [peri-endoscopy(8 h) group],whereas 17/70(24.3%) received antibiotics at > 8 h after endoscopy or not at all(non peri-endoscopy group).Overall mortality and rebleeding rates were 13/70(18.6%) and 14/70(20%),*** periendoscopy(8 h) group was significantly less likely to die compared with the non peri-endoscopy group [13.2% vs 35.3%,P = 0.04,odds ratio(OR) = 0.28(0.078-0.997)] and showed a trend towards reduced rebleeding [17.0% vs 29.4%,P = 0.27,OR = 0.49(0.14-1.74)].On univariate analysis,the non peri-endoscopy group [P = 0.02,OR = 3.58(1.00-12.81)],higher mode

关键词： Variceal hemorrhage Mortality Antibiotics Prophylaxis Clostridium difficile

Effects of vertical position on trematode parasitism in larval anurans

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Current Zoology 2019年第6期65卷 657-664页

作者： Jacob R.jones Camille l.STEENROD John A.MARINO Jr. Biology Department Bradley UniversityPeoriaILUSA Department of Geography University of MarylandCollege ParkMDUSA

Spatial distributions of animals can affect interactions with their natural enemies,such as parasites,and thus have important implications for host-parasite *** spatial variation in infection risk has been explored in many systems at the landscape scale,less attention has been paid to spatial structure at smaller ***,we explore a hypothesized relationship between a common spatial variable,vertical position,and risk of parasite infection in a model aquatic system,larval frogs(Rana)and trematode(Digenea)*** position is relevant to this system given evidence that the densities of snail first intermediate hosts,tadpole second intermediate hosts,and trematode infective stages can vary with *** test the effects of depth on infection risk of larval frogs by trematodes,we performed two enclosure experiments,one in the laboratory and one in the field,in which larval frogs in cages just below the water surface or near the bottom of the water column were exposed to *** with near-surface cages,mean infection load(number of cysts)in tadpoles in near-bottom cages was 83%higher after 48-h exposures in the laboratory and 730%higher after 10-day exposures in the *** findings thus indicate that infection risk depends on depth,which may have adaptive significance,as tadpoles have previously been shown to change vertical position in response to parasite *** results motivate future work examining vertical variation in infection risk and may have broader implications for host-parasite dynamics and evolution of host and parasite behavior.

关键词： avoidance behavior cercariae Echinostomatidae host-parasite interactions Rana spatial structure

Response of nitrogen fractions in the rhizosphere and bulk soil to organic mulching in an urban forest plantation

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Journal of Forestry Research 2021年第6期32卷 2577-2588页

作者： Xiaodan Sun Gang Wang Yuqian Ye Qingxu Ma Qingwei Guan Davey l.jones College of Biology and the Environment Nanjing Forestry UniversityNanjing 210037People’s Republic of China Co-Innovation Center for Sustainable Forestry in Southern China Nanjing 210037People’s Republic of China School of Natural Sciences Bangor UniversityBangor LL572UWGwyneddUK

Nitrogen is an essential component in forest ecosystem nutrient *** fractions,such as dissolved nitrogen,ammonium,nitrate,and microbial biomass nitrogen,are sensitive indicators of soil nitrogen pools which affect soil fertility and nutrient ***,the responses of nitrogen fractions in forest soils to organic mulching are less well *** rhizosphere is an important micro-region that must be considered to better understand element cycling between plants and the soil.A field investigation was carried out on the effect of mulching soil in a 15-year-old ligustrum lucidum urban *** in total nitrogen and nitrogen fractions in rhizosphere and bulk soil in the topsoil(upper 20 cm)and in the subsoil(20-40 cm)were evaluated following different levels of mulching,in addition to nitrogen contents in fine roots,leaves,and organic *** relationships between nitrogen fractions and other measured variables were *** mulching had no significant effect on most nitrogen fractions except for the rhizosphere microbial biomass nitrogen(MBN),and the thinnest(5 cm)mulching layer showed greater effects than other *** MBN was more sensitive to mulching compared to bulk soil,and was more affected by soil environmental *** and soil depth had more pronounced effects on nitrogen fractions than *** nitrogen and dissolved nitrogen were correlated to soil phosphorus,whereas other nitrogen fractions were strongly affected by soil physical properties(temperature,water content,bulk density).Mulching also decreased leaf nitrogen content,which was more related to soil nitrogen fractions(except for MBN)than nitrogen contents in either fine roots or organic *** applications of small quantities of organic mulch contribute to nitrogen transformation and utilization in urban forests.

关键词： Rhizosphere Nitrogen fraction Organic mulching Soil–plant interaction Urban plantation forest

DETERMINE ON INITIAl DIMENSIONAl STABIlITY OF CHEMICAl MODIFIED WOOD

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Journal of Northeast Forestry University 1991年第1期2卷 70-78页

作者： Banks W. B. jones G.l. North Wales University North Wales University United KingdomUnited Kingdom

Strain development along radial direction was continuously determined by D-200 linear Variable Differential Transformers (l.V.D.T). When a wood specimen was put into water and begin to swell from absolute dry moisture content to the maximum. Experiment results show that the differences of swelling with soaking time between untreated and treated wood specimens due to uptaking water. It would also give an indication to the effectiveness of various chemicals on the dimensional stability of modified wood. ASE of modified wood samples with SA-EP, EP and SA were found to be better than MA-AGE. SA-EP had got the best effetivencss on dimensional stability in reducing the swelling.

关键词： Swelling Determination Modified wood

Association between fundamental motor skills and physical activity in the early years:A systematic review and meta-analysis

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Journal of Sport and Health Science 2020年第6期9卷 542-552页

作者： Dan jones Alison Innerd Emma l.Giles liane B.Azevedo School of Health and life Sciences Teesside UniversityMiddlesbrough TS13BXUK

Background:Physical activity(PA)in the early years is associated with a range of positive health *** motor skill(FMS)competence is associated with PA and is theorized to be driven by PA in the early years and vice versa in mid to late ***,to date,no studies have meta-analyzed the association between PA and FMS in the early ***:Six electronic databases were searched for articles published up to April ***-sectional and longitudinal studies were included if they targeted children(ages 3-6 year)as the population of the study and assessed the association between objectively measured PA and *** FMS,total physical activity(TPA),and moderate-to-vigorous physical activity(MVPA)data were meta-analyzed using a random effects ***:We identified 24,815 titles and *** total,19 studies met the inclusion criteria,including 14 cross-sectional and 4 longitudinal studies,as well as 1 study with cross-sectional and longitudinal *** was a significant but small positive association between FMS and MVPA(r=0.20,95%confidence interval(CI):0.13-0.26)and TPA(r=0.20,95%CI:0.12-0.28).Findings from longitudinal studies revealed that PA drives FMS in early *** was explored in 1 study,which found that perceived motor competence did not mediate the association between FMS and ***:Using a meta-analysis,this study is the first to show a positive association between FMS,MVPA,and TPA in the early years of childhood,suggesting that the association begins at an early *** evidence from longitudinal studies supports the theory that PA drives FMS in the early years of *** evidence is needed from large studies to track PA and FMS until mid to late childhood and to explore the mediators of this association.

关键词： Early years Fundamental motor skills Physical activity

Selective androgen receptor modulators for the treatment of late onset male hypogonadism

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Asian Journal of Andrology 2014年第2期16卷 256-261,I0009页

作者： Christopher C Coss Amanda jones Michael l Hancock Mitchell S Steiner James T Dalton GTx Inc. Memphis Tennessee USA.

Several testosterone preparations are used in the treatment of hypogonadism in the ageing male. These therapies differ in their convenience, flexibility, regional availability and expense but share their pharmacokinetic basis of approval and dearth of long-term safety data. The brevity and relatively reduced cost of pharmacokinetic based registration trials provides little commercial incentive to develop improved novel therapies for the treatment of late onset male hypogonadism. Selective androgen receptor modulators （SARMs） have been shown to provide anabolic benefit in the absence of androgenic effects on prostate, hair and skin. Current clinical development for SARMs is focused on acute muscle wasting conditions with defined clinical endpoints of physical function and lean body mass. Similar regulatory clarity concerning clinical deficits in men with hypogonadism is required before the beneficial pharmacology and desirable pharmacokinetics of SARMs can be employed in the treatment of late onset male hypogonadism.

关键词： hypogonadism late onset hypogonadism selective androgen receptor modulators testosterone

Application of ^(14)N(d,α)^(12)C Nuclear Reaction to the Concentration Analysis of Nitrogen in Iron Meteorites

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Chinese Physics letters 1995年第5期12卷 265-268页

作者： HU Beilai A.l.Hanson K.W.jones Department of Physics Nankai UniversityTianjin 300071 Brookhaven National laboratory UptonNew York 11973U.S.A.

The ^(14)N(d,α)^(12)C nuclear reaction has been used to measure the nitrogen content in iron *** analysis was made with 2.0MeV^(2)H^(+) beam from Brookhaven 3.5MV research electrostatic *** detection limits of about ... 详细信息

关键词： electrostatic beam

Do coyotes Canis latrans influence occupancy ot prey in suburban forest fragments？

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Current Zoology 2016年第1期62卷 1-6页

作者： Brandon M. jones Michael V. COVE Marcus A. lASHlEY Victoria l. JACKSON Department of Biology and Agriculture University of Central Missouri Warrensburg M0 64093 USA Department of Applied Ecology North Carolina State University Raleigh NC 27695 USA Department of Forestry and Environmental Resources North Carolina State University Raleigh NC 27695 USA Department of Wildlife Fisheries and Aquaculture Mississippi State University Starkville MS 39762 USA

With the extirpation of apex predators from many North American systems, coyotes Canis latrans have become the de facto top predator and are ubiquitous members of most ecosystems. Keystone predators aid in maintaining ecosystem function by regulating the mammal community through direct predation and instilling the landscape of fear, yet the value of coyotes regulating systems to this capacity is understudied and likely variable across environments. Since coyotes are common in the Midwestern United States, we utilized camera traps and occupancy analyses to as- sess their role in regulating the distribution of mammalian herbivores in a fragmented suburban ecosystem. Forest cover was a strong positive predictor of white-tailed deer Odocoileus virginianus detection, while coyote occurrence had a negative effect. Coyotes exerted a negative effect on squirrel （Sciurus spp.） and eastern cottontail rabbit Sylvilagus floridanus occurrence, while urban cover was a positive predictor for the prey species＇ occurrence. These results suggest all 3 species behaviorally avoid coyotes whereby deer seek denser forest cover and squirrels and cottontails mitigate risk by increasing use of urban areas. Although previous studies reveal limited influence of coyote on the rest of the carnivore guild in suburban systems, we suggest coyotes play an important role in regulating the herbivorous mammals and hence may provide similar eco- logical, benefits in urban/suburban forest fragments through trophic cascades. Furthermore, since hunting may not be allowed in urban and suburban habitats, coyotes might also serve as the pri- mary regulator of nuisance species occurring at high abundance such as white-tailed deer and squirrels.

关键词： camera traps coyote deer rabbit squirrel urban wildlife.