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Rapid, cost-effective DNA quantification via a visuallydetectable aggregation of superparamagnetic silicamagnetite nanoparticles

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Nano Research 2014年第5期7卷 755-764页

作者： Qian Liu Jingyi Li Hongxue Liu Ibrahim Tora Matthew s. Ide Jiwei Lu Robert J. davis David L. Green james P. Landers Department of Chemistry University of Virginia McCormick Road P. O. Box 400319 Charlottesville 22904 Virginia USA Department of Pathology University of Virginia Health Science Center Charlottesville 22908 Virginia USA Department of Mechanical Engineering University of Virginia Charlottesville 22904 Virginia USA Center for Microsystems forthe Life sciences University of Virginia Charlottesville 22904 Virginia USA Department of Materials science & Engineering University of Virginia P. O. Box 400745 395 McCormick Road Charlottesville 22904-4745 Virginia USA Department of Chemical Engineering University of Virginia. 123 Engineers Way Charlottesville 22904 Virginia USA

DNA and silica-coated magnetic particles entangle and form visible aggregates under chaotropic conditions with a rotating magnetic field, in a manner that enables quantification of DNA by image analysis. As a means of exploring the mechanism of this DNA quantitation assay, nanoscale siO2-coated Fe304 （Fe3O4@siO2） particles are synthesized via a solvothermal method. Characterization of the particles defines them to be -200 nm in diameter with a large surface area （141.89 m2/g）, possessing superparamagnetic properties and exhibiting high saturation magnetization （38 emu/g）. The synthesized Fe3O4@siO2 nanoparticles are exploited in the DNA quantification assay and, as predicted, the nanoparticles provide better sensitivity than commercial microscale Dynabeads for quantifying DNA, with a detection limit of 4 kilobase-pair fragments of human DNA. Their utility is proven using nanoparticle DNA quantification to guide efficient polymerase chain reaction （PCR） amplification of short tandem repeat loci for human identification.

关键词： silica/magnetite core-shell superparamagnetic DNA quantification polymerase chain reaction(PCR)

A linear regression model (LRM) for groundwater chemistry in and around the Vaniyambadi industrial area, Tamil Nadu, India

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Chinese Journal Of Geochemistry 2013年第1期32卷 19-26页

作者： sajil Kumar P.J. davis Delson P. Vernon J.G. james E.J. Brandenburg Technical University Cottbus-03046 Germany ITALCONsULT Riyadh-11421 Saudi Arabia Budapest University of Technology and Economics (BME) Budapest-Pf. 91 H-152 Hungary Water Institute Karunya UniversityCoimbatore-641114 India

A linear regression model in conjunction with cluster analysis was applied to the groundwater quality parameters for the Vaniyambadi industrial area, Tamil Nadu, India. These physico-chemical parameters were collected from 25 wells by intensive groundwater sampling conducted during January 2010. All the major ions, pH and electrical conductivity were analyzed. The abundances of cations were in the order of Na se of anions were in the order of Cl sO4 spectively. This was in agreement with the water types, Na-Cl and Na-Ca-HCO3, determined by the Piper plot. High concentrations of the ions Na, Cl and sO4 were recorded near the tanneries that operate within the study area. While the elevated concentrations of HCO3 and F were observed away from the tanneries. This peculiar hydrochemical behaviour suggests that the chemistry of water is predominantly influenced by tannery effluents and weathering of silicate minerals. Results of the linear regression model yielded 11 regression equations for the 5 most correlated parameters. A dendrogram from the cluster analysis showed 2 major clusters representing the influence of tanneries and geological formations in the study area, which confirmed the results of major ion chemistry.

关键词：线性回归模型地下水化学工业区印度 LRM 聚类分析物理化学参数研究区域

Host plant selection of Chrysolina clathrata （Coleoptera： Chrysomelidae） from Mpumalanga, south Africa

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Insect science 2009年第1期16卷 81-88页

作者： Robert s. Boyd Micheal A. davis Michael A. Wall Kevin Balkwill Department of Biological sciences Auburn University Auburn Alabama Department of Biological sciences University of Southern Mississippi Hattiesburg Mississippi Entomology Department San Diego Natural History Museum San Diego California USA C.E. Moss Herbarium School of Animal and Plant Sciences University of the Witwatersrand Private Bag 3 WITS 2050 Johannesburg South Africa

Hyperaccumulated elements such as Ni may defend plants against some natural enemies whereas other enemies may circumvent this defense. The Ni hyperaccumulator Berkheya coddii Roessler （Asteraceae） is a host plant species for Chrysolina clathrata （Clark）, which suffers no apparent harm by consuming its leaf tissue. Beetle specimens collected from B. coddii had a whole body Ni concentration of 260μg/g dry weight, despite consuming leaf material containing 15 100μg Ni/g. Two experiments were conducted with adults of this beetle species： a no-choice experiment and a choice experiment. In the nochoice experiment we offered beetles foliage of one of four speeies ofBerkheya： B. coddii, B. rehmannii Thell. var. rogersiana Thell., B. echinacea （Harv.） O. Hoffm. ex Burtt Davey, and B. insignis （Harv.） Thell. The two former species are Ni hyperaccumulators （defined as having leafNi concentration 〉 1 000 μg/g） whereas the latter have low Ni levels （〈 200 μg/g） in their leaves. Masses of beetles were monitored for 6 days. Choice experiments used growing stem tips from the same Berkheya species, placed into Petri dishes with five Chrysolina beetles in each, and the amount of feeding damage caused on each of the four species was recorded. Beetles in the no-choice experiment gained mass when offered B. coddii, maintained mass on leaves of the other Ni hyperaccumulator （B. rehmannii var. rogersiana）, and lost mass when offered non-hyperaccumulator leaves. In the choice test, beetles strongly preferred B. coddii to other Berkheya species. We conclude that C. clathrata may be host-specific on B. coddii.

关键词： Berkheya coddii bioaccumulation heavy metals host plant specialist nickel

Host-herbivore studies of stenoscepa sp. （Orthoptera：Pyrgomorphidae）, a high-Ni herbivore of the south African Ni hyperaccumulator Berkheya coddii （Asteraceae）

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Insect science 2007年第2期14卷 133-143页

作者： ROBERT s. BOYD MICHEAL A. davis MICHAEL A. WALL KEVIN BALKWILL Department of Biological sciences Auburn University Auburn Alabama University of the Witwatersrand Johannesburg South Africa Department of Biological sciences University of Southern Mississippi Hattiesburg MS University of the Witwatersrand Johannesburg South Africa Entomology Department San Diego Natural History Museum San Diego California USA C.E. Moss Herbarium School of Animal and Plant Sciences University of the Witwatersrand Johannesburg South Africa

Nymphs of stenoscepa sp. feed on leaves of the Ni hyperaccumulator Berkheya coddii at serpentine sites in Mpumalanga Province, south Africa. These sites contain Ni hyperaccumulators, Ni accumulators, and plants with Ni concentrations in the normal range. We conducted studies to：（i） determine the whole-body metal concentration of nymphs （including those starved to empty their guts）; （ii） compare stenoscepa sp. nymphs against other grasshoppers in the same habitat for whole-body metal concentrations; and （iii）compare the suitability of Ni hyperaccumulator and Ni accumulator plants as food sources for stenoscepa sp. and other grasshoppers. stenoscepa nymphs had extremely high whole-body Ni concentrations （3 500μg Ni/g）. This was partly due to food in the gut, as starved insects contained less Ni （950 pg Ni/g）. stenoscepa nymphs survived significantly better than other grasshoppers collected from either a serpentine or a non-serpentine site when offered high-Ni plants as food. In a host preference test among four Berkheya species （two Ni hyperaccumulators and two Ni accumulators）, stenoscepa sp, preferred leaves of the Ni hyperaccumulator species. A preference experiment using leaves of three senecio species （of which one species, senecio coronatus, was represented by both a Ni hyperaccumulator and a Ni accumulator population） showed that stenoscepa sp. preferred Ni accumulator senecio coronatus leaves to all other choices. We conclude that stenoscepa sp. is extremely Ni-tolerant. stenoscepa sp. nymphs prefer leaves of hyperaccumulator Berkheya species, but elevated Ni concentration alone does not determine their food preference. We suggest that the extremely high whole-body Ni concentration of stenoscepa nymphs may affect food web relationships in these serpentine communities.

关键词： Berkheya coddii biomagnification food webs heavy metals hyperaccumulation,south Africa

Implicit Continuous User Authentication for Mobile Devices based on Deep Reinforcement Learning

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Computer systems science & Engineering 2023年第2期44卷 1357-1372页

作者： Christy james Jose M.s.Rajasree Government Engineering College Idukki685603India APJ Abdul Kalam Technological University Thiruvananthapuram695016India

The predominant method for smart phone accessing is conﬁned to methods directing the authentication by means of Point-of-Entry that heavily depend on physiological biometrics like,ﬁngerprint or *** continuous authentication initiating to be loftier to conventional authentication mechanisms by continuously conﬁrming users’identities on continuing basis and mark the instant at which an illegitimate hacker grasps dominance of the ***,divergent issues remain *** research aims to investigate the power of Deep Reinforcement Learning technique to implicit continuous authentication for mobile devices using a method called,Gaussian Weighted Cauchy Kriging-based Continuous Czekanowski’s(GWCK-CC).First,a Gaussian Weighted Non-local Mean Filter Preprocessing model is applied for reducing the noise pre-sent in the raw input face *** Kriging Regression function is employed to reduce the ***,Continuous Czekanowski’s Clas-siﬁcation is utilized for proﬁcient classiﬁcation between the genuine user and *** this way,the proposed GWCK-CC method achieves accurate authen-tication with minimum error rate and *** assessment of the pro-posed GWCK-CC method and existing methods are carried out with different factors by using UMDAA-02 Face *** results conﬁrm that the proposed GWCK-CC method enhances authentication accuracy,by 9%,reduces the authen-tication time,and error rate by 44%,and 43%as compared to the existing methods.

关键词： Deep reinforcement learning gaussian weighted non-local meanﬁlter cauchy kriging regression continuous czekanowski’s implicit continuous authentication mobile devices

Estimating REY content of eastern Kentucky coal samples based on their associated ash elements

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Journal of Rare Earths 2018年第11期36卷 1234-1238页

作者： s.Chehreh Chelgani james C.Hower Department of Electrical Engineering and Computer science University of Michigan Center for Applied Energy Research University of Kentucky

Coal and coal combustion byproducts can be considered as an alternative source of rare earth elements and yttrium （REY）. The study of relationships between REY and other main coal properties could have several advantages such as estimating REY content of coal particles and designing beneficial extraction method. In this investigation, inter-correlations between REY content with coal parameters （proximate and ash elements） for a wide range of eastern Kentucky coal samples （708 records） were explored. Results demonstrate that zircon and monazite are the main source of heavy and light rare earth elements （HREE and LREE）, respectively. Zr has the highest correlation with Y and Th has the strength relationship with Ce and La. In general, LREE have higher interaction with coal ash content in comparison with HREE. Results indicated that REY can be estimated quite satisfactorily by using their associated elements in coal ash.

关键词： Coal Heavy rare earth Light rare earth Proximate Ash elements

Alterations in gastric mucin synthesis by Helicobacter pylori

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World Journal of Gastroenterology 2000年第4期6卷 475-482页

作者： james C. Byrd Robert s. Bresalier Gastrointestinal Cancer Research Laboratory Henry Ford Health Sciences CenterDetroitMIUSA Gastrointestinal Cancer Research Laboratory Henry Ford Health Sciences CenterDetroitMIUSA Department of MedicineUniversity of Michigan School of MedicineAnn ArborMIUSA

INTRODUCTIONHelicobacter pylori is recognized as a cause of chronicactive gastritis,gastric and duodenal ulcers,and gastriccancer,though the mechanisms of pathogenesis for ***-associated diseases are not yet well *** ... 详细信息

关键词： gastric mucin Helicobacter pylori

Methodology to locate and quantify radial winding deformation in power transformers

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High Voltage 2017年第1期2卷 17-24页

作者： steven D.Mitche james s.Wesh school of Electrical and Computer Engineering University of NewcastleCallaghanN.S.W 2308Australia

Frequency response analysis(FRA)is a tool that can be used to detect changes within the structural geometry of a *** application of FRA is to detect winding displacement after the transformer experiences an overcurrent *** paper proposes a methodology which will facilitate both locating and quantifying winding *** procedure is based on the fitting of a Gray Box transformer model to FRA measurements which were recorded both before and after the *** variation in key parameters of the model can then be used to quantify winding deformation *** research will demonstrate the applicability of this approach to a wide range of transformer applications by using FRA from a modified 1.3 MVA distribution transformer,and assessing the change in key parameters relative to the emulated buckling introduced to the *** authors propose that this approach is ideally suited for use within an automated diagnostic system which will locate,diagnose and quantify winding deformation within power transformers.

关键词： winding deformation power

CO_(2)Emissions Post-COP26:Who is Responsible to Curb the Flow?Does it Matter if We Can Make it a Win-Win?

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Energy & Environmental Materials 2022年第3期5卷 683-685页

作者： james Crawshaw s.Ravi P.silva Advanced Technology Institute University of SurreyGuildfordUK

The debate about climate change is highly *** everyone is convinced that CO_(2)emissions are worth curbing despite seemingly irrefutable evidence in the IPCC’s latest report.[1]some have vested interests in exploiting fossil fuels while others think alternative,cheaper solutions can be *** that have shifted from manufacturing to service-based economies will find it easier to *** countries with relatively low carbon emissions per capita but large populations believe it is unfair that they should have to bear heavy costs of decarbonization to solve a problem that wealthier countries have created.

关键词： Who is Responsible to Curb the Flow CO_(2)Emissions Post-COP26 Does it Matter if We Can Make it a Win-Win