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Chinese Journal Of Geochemistry 2010年第2期29卷 167-174页

作者： Nganje t.N. Adamu C.I. Ukpong e.e. Department of Geology University of Calabar Formerly Department of Geology University of Calabar

this study focused on the influence of base metal mining on heavy metal levels in soils and plants in the vicinity of Arufu lead-zinc mine, Nigeria. Soil samples (0-15 cm depth) and plant samples were collected from cul-tivated farmlands in and around the mine, the unmineralized site and a nearby forest (the control site). the samples were analyzed for heavy metals (Fe, Zn, Mn, Cu, Pb, Cr and Cd) by Atomic Absorption Spectrophotometry (AAS). the physical properties of soils (pH and LOI) were also measured. Results showed that soils from cultivated farm-lands have neutral pH values (6.5-7.5), and low organic matter contents (evels of Zn, Pb and Cd in culti-vated soils were higher than the concentrations obtained from the control site. these heavy metals are most probably sourced from mining and agricultural activities in the study area. Heavy metal concentrations measured in plant parts decreased in the order of rice leaves>cassava tubers>peelings. In the same plant species, metal levels decreased in the order of Zn>Fe>Mn>Cu>Pb>Cr>Cd. Most heavy metals were found in plant parts at average concentrations normally observed in plants grown in uncontaminated soil, however, elevated concentrations of Pb and Cd were found in a few cassava samples close to the mine dump. A stepwise linear regression analysis identified soil metal contents, pH and LOI as some of the factors influencing soil-plant metal uptake.

关键词：土壤重金属含量土壤样品植物样本铅锌矿尼日利亚原子吸收光谱法线性回归分析 amp

A pharmacologist's journey in medical education:a personal history

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Acta Pharmacologica Sinica 2004年第9期25卷 102-106页

作者： e e DANIeL AB t6G 2H7 Canada Department of Pharmacology Room 9-10 edmonton MSB University of Alberta

My journey as an educator in Pharmacology began in 1949, when, after finishing my MA in Biology at Johns Hopkins, Ⅰ decided that Ⅰ wanted to be involved in science with more relevance to humans. Ⅰhad been chasing f... 详细信息

关键词： ACe A pharmacologist’s journey in medical education

Long-time Shoreline Monitoring of the Vellar estuarine Complex,Southeast Coast of India:Using Multispectral Satellite Data

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Journal of earth Science 2012年第6期23卷 900-907页

作者： L Senthilnathan e P Nobi t thangaradjou L Kannan Centre of Advanced Study in Marine Biology Faculty of Marine SciencesAnnamalai UniversityParangipettai-608502TamilnaduIndia

the present study was carried out to track the path of Vellar estuary over a period of 38 years （1970-2008） and also to detect the impact of tsunami on estuarine complex of the Vellar estuary. Visual interpretation techniques were employed by using muitispectral data of Landsat tM （1991） and IRS-P6 LISS III （2004, 2006, and 2008） to delineate shoreline changes in the VeUar estuarine complex. Results clearly revealed the changes that occurred along the estuarine path over the period, and severe erosion was noticed in the seaward side of the MGR thittu and accretion, along the estuarine mouth. It is also visible that there is clear river path shift in the river course. Although the sandbar formation was seen with only little morphologic modification up to 2004, the Indian Ocean tsunami that struck this coast （26 December, 2004） distorted the sandbar of the Vellar estuarine mouth; however, the 2006 satel- lite images confirmed that the sandbar was formed again to its original structure as that of before the tsunami.

关键词： estuary geomorphology IRS-P6 LISS III shoreline tsunami India.

Lysozyme as an alternative to growth promoting antibiotics in swine production

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Journal of Animal Science and Biotechnology 2016年第1期7卷 34-40页

作者： W. t. Oliver J.e.Wells USDA ARS U.S. Meat Animal Research Center P. O. Box 166 Clay Center NE68933-0166 USA

Lysozyme is a naturally occurring enzyme found in bodily secretions such as tears, saliva, and milk. It functions as an antimicrobial agent by cleaving the peptidoglycan component of bacterial cell walls, which leads to cell death. Antibiotics are also antimicrobials and have been fed at subtherapeutic levels to swine as growth promoters. these compounds benefit swine producers by minimizing production losses by increasing feed efficiency and decreasing susceptibility to bacterial infection and disease. this manuscript reviews the knowledge of the effects of lysozyme, as compared to traditional subtherapeutic antibiotics in swine feed, on pig performance and health. It is clear from decades of studies that antibiotic use in feeds increases pig performance, particularly in the nursery. Similarly, lysozyme, as a feed additive, increases growth and feed efficiency. While the mechanism by which antibiotics and lysozyme improve performance is not clearly understood, both of these feed additives improve gastrointestinal health, improve the metabolic profile, and alter the gastrointestinal bacteria ecology of swine. therefore, lysozyme is a suitable alternative to growth-promoting subtherapeutic antibiotic use in swine feed.

关键词： Antibiotics Gastrointestinal Lysozyme Microbiota Review Swine

Long-term trends in extreme temperatures in Hong Kong and Southern China

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Advances in Atmospheric Sciences 2011年第1期28卷 147-157页

作者： t.C.Lee e.W.L.GINN Hong Kong Observatory

the observed long-term trends in extreme temperatures in Hong Kong were studied based on the meteorological data recorded at the Hong Kong Observatory Headquarters from 1885-2008. Results show that, over the past 124 years, the extreme daily minimum and maximum temperatures, as well as the length of the warm spell in Hong Kong, exhibit statistically significant long-term rising trends, while the length of the cold spell shows a statistically significant decreasing trend. the time-dependent return period analysis also indicated that the return period for daily minimum temperature at 4°C or lower lengthened considerably from 6 years in 1900 to over 150 years in 2000, while the return periods for daily maximum temperature reaching 35°C or above shortened drastically from 32 years in 1900 to 4.5 years in 2000. Past trends in extreme temperatures from selected weather stations in southern China from 1951-2004 were also assessed. Over 70% of the stations studied yielded a statistically significant rising trend in extreme daily minimum temperature, while the trend for extreme maximum temperatures was found to vary, with no significant trend established for the majority of stations.

关键词： extreme temperature long-term trend Hong Kong southern China

ANFIS-based approach to studying subthreshold behavior including the traps effect for nanoscale thin-film DG MOSFets

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Journal of Semiconductors 2013年第8期34卷 43-51页

作者： t.Bentrcia F.Djeffal e.Chebaaki Department of Physics University of Batna LeA Department of ElectronicsUniversity of Batna LePCM Department of PhysicsUniversity of Batna

A fuzzy framework based on an adaptive network fuzzy inference system（ANFIS） is proposed to evaluate the relative degradation of the basic subthreshold parameters due to hot-carrier effects for nanoscale thin-film double-gate（DG） *** effect of the channel length and thickness on the resulting degradation is addressed, and 2-D numerical simulations are used for the elaboration of the training *** membership function shapes are developed,and the best one in terms of accuracy is *** predicted results agree well with the 2-D numerical simulations and can be efficiently used to investigate the impact of the interface fixed charges and quantum confinement on nanoscale DG MOSFet subthreshold ***,the proposed ANFIS-based approach offers a simple and accurate technique to study nanoscale devices,including the hot-carrier and quantum effects.

关键词： hot-carrier degradation ANFIS fuzzy computation subthreshold quantum effects thin film

Clinical pharmacology relevant to older adults with cardiovascular disease

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Journal of Geriatric Cardiology 2015年第3期12卷 192-195页

作者： Jorge A Brenes-Salazar Laith Alshawabkeh Kenneth e Schmader Joseph t Hanlon Daniel e Forman Department of Medicine Division of Cardiovascular Diseases Mayo Clinic Rochester MN USA Department of Medicine Division of Cardiovascular Medicine University of lowa Iowa City IA USA Department of Medicine Division of Geriatrics Duke University School of Medicine Durham NC USA Departments of Medicine (Division of Geriatric Medicine) Pharmacy and Epidemiology University of Pittsburgh Geriatric Research Education and Clini- cal Center and Center for Health Equity Research and Promotion VA Pittsburgh Health System Pittsburgh PA USA Department of Medicine (Divisions of Geriatric Medicine and Cardiology) University of Pittsburgh Medical Center Geriatric Research Education and Clinical Center VA Pittsburgh Health System Pittsburgh PA USA

1 Introduction Although older adults are generally among the highest users of cardiovascular medications, they are typically underrepresented or excluded from most efficacy and safety trials. Drug developers are usually reluctant to include many senior adults in randomized controlled clinical trials in part due to their high prevalence of multiple comorbidities, frailty, and polypharmacy; and to age-related pharmacokinetic and pharmacodynamic complexities. Consequently, there is often insufficient high quality evidence-based data to inform pharmacologic management of common cardiovascular conditions on older adults. In the absence of data, clinicians often rely on conceptual principles regarding metabolism and drug-drug interactions to minimize adverse drug events, but this is often not well-substantiated or standardized. A related challenge is poor cardiovascular medication adherence among older adults, and its detrimental impact on their health outcomes. In this brief review we highlight some aspects of these topics.

关键词： Metabolism Pharmacokinetics Pharmacodynamics Polypharmacy

Validation of CFD-DeM model for iron ore reduction at particle level and parametric study

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Particuology 2020年第4期18卷 163-172页

作者： Dianyu e International Research Institute for Minerals Metallurgy and MaterialsJiangxi University of Science and TechnologyNanchang 330013China Department of Chemical engineering Monash UniversityClaytonVIC 3800Australia

Iron ore reduction is a primary unit operation in current metallurgy processes and dominates the energy consumption and greenhouse gas(GHG)emissions of the iron-making process,therefore,even a slight improvement of the energy efficiency or GHG emissions of iron ore reduction would yield considerable benefits to the cost of pig iron and,more importantly,to mitigation of the associated carbon *** current study presents a discrete model that describes the iron ore reduction process for a single *** transient reaction progress can be predicted and is validated against experimental measurements under various operating conditions,including different reducing gases and *** effects of pressure,isothermality,gas composition,and flow rate on reduction are *** reduction rate increases significantly with increasing pressure until 5 atm,and the entire reduction process occurs more slowly under non-isothermal conditions than under isothermal *** work provides a solid foundation for the development of a comprehensive particulate system model that considers both heat and mass transfer.

关键词： Iron ore reduction Chemical reaction Blast furnace Discrete element method Computational fluid dynamics

Mitigation of eDFA transient effects in variable duty cycle pulsed signals

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Defence technology（防务技术） 2019年第3期15卷 276-281页

作者： D. Meena K.t. Sarath Fredy Francis e. Dipin t. Srinivas electronics and Radar Development establishment (LRDe) DRDO Bangalore Karnataka 560093 India Model engineering College Thrikkakara Cochin Kerala 682021 India Indian Institute of technology Madras Chennai Tamil Nadu 600036 India

We report the transient effects in erbium Doped Fiber Amplifier (eDFA) systems for pulsed signals with different duty-cycles. the work includes the analysis using three different duty-cycles, 10%, 20% and 50%. A curve fitting technique is also proposed to predict the transients of any lesser duty-cycled pulse, once the transients of a larger duty-cycled pulse is known. Mathematical evaluation confirms the double exponential shape of transient distorted signal. Further, eDFA transient effect is experimentally verified on a Wavelength Division Multiplexed (WDM) link by multiplexing high and low bitrate modulated optical signals. We conclude the paper by proposing a transient suppression technique for variable dutycycle signals and analyzing its effectiveness with different wavelength spacing.

关键词： eDFA transients WDM Variable duty cycle Suppression

Community-level trait responses and intra-specific trait variability play important roles in driving community productivity in an alpine meadow on the tibetan Plateau

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Journal of Plant ecology 2017年第4期10卷 592-600页

作者： Wei Li Jie Zhao Howard e.epstein Guanghua Jing Jimin Cheng Guozhen du State Key Laboratory of Soil erosion and Dryland Farming on the Loess Plateau Northwest A&F University26 Xinong RoadYangling 712100China Institute of Soil and Water Conservation Chinese Academy of Sciences&Ministry of Water Resource26 Xinong RoadYangling 712100China College of Animal Science and technology Northwest A&F University22 Xinong RoadYangling 712100China Department of environmental Sciences University of Virginia291 McCormick RoadCharlottesvilleVA 22904-4123USA School of Life Sciences Lanzhou University222 Tianshui RoadLanzhou 730000China

Aims Human activities have dramatically increased nutrient inputs to ecosys-tems,impacting plant community diversity,composition and *** research has shown that a decrease in species diversity and an increase in productivity are a common phenomenon following fertilization in grasslands *** magnitude of the response of species diversity and above-ground net primary productivity(ANPP)to fertilization mainly depends on species traits(mean trait values)and traits variability(plasticity).Our aim of this study was to examine(i)changes of species diversity(species richness and Shannon-Wiener index)and ANPP following fertilization;(ii)which species traits or community-weighted mean(CWM)traits can determine ANPP,as expected from the‘biomass ratio hypothesis’;and(iii)the relative role of intra-specific and inter-specific trait variability in this process following *** We measured ANPP and four key plant functional traits:specific leaf area(SLA),leaf dry matter content(LDMC),mature plant height(MPH)and leaf nitrogen concentration(LNC)for 25 component species along a fertilization gradient in an alpine meadow on the tibetan *** addition,trait variation of species was assessed using coefficients of variation(CV),and we calculated the ratio of the CVintra to the *** Findings Our results showed that:(i)fertilization significantly reduced species richness and Shannon-Weiner diversity index,but sig-nificantly increased ANPP;(ii)there was a significant positive correlation between ANPP and CWM-SLA and CWM-MPH,yet there was no significant relationship between ANPP and CWM-LNC or CWM-LDMC;(iii)intra-specific variability in SLA and MPH was found to be much greater than inter-specific variability,especially at the higher fertilization *** con-cluded that CWM-SLA and CWM-MPH can be used to assess the impacts of species changes on ecosystem functioning,and dominant species can maximize resource use through intra-spe-

关键词： biomass ratio hypothesis fertilization leaf dry matter content leaf nitrogen concentration mature plant height specific leaf area tibetan Plateau