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Evaluation of method performance for osteometric sorting of commingled human remains

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Forensic Sciences Research 2018年第4期3卷 343-349页

作者： John E.byrd carrie b.LeGarde Laboratory Defense POW/MIA Accounting AgencyJoint Base Pearl Harbor-HickamHIUSA

Evaluation of method performance involves the consideration of numerous factors that can contribute to error.A variety of measures of performance can be borrowed from the signal detection literature and others are drawn from statistical *** article demonstrates the principles of performance evaluation by applying multiple measures to osteometric sorting models for paired elements run against data from known *** indicate that false positive rates are close,on average,to expected *** assemblage size grows,the false positive rate becomes unimportant and the false negative rate becomes *** disparity among the commingled individuals plays a significant role in method performance,showing that case-specific circumstances(*** size and size disparity)will determine method power.

关键词： Forensic sciences forensic anthropology statistics test method method performance error signal detection osteometric sorting

The HIPERC Project:the Use of Nb for High Performance and Economy in Steel for Linepipe and General Structural Use

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Journal of Iron and Steel Research International 2011年第S1期18卷 690-695页

作者： webster Stephen Drewett Lyn Consultant UK Tata Steel RD&T Swinden Technology CentreRotherhamUK

The HIPERC study was a European research project involving several steel companies and research organisations which examined the effects of alloying elements and processing conditions in low carbon (bium containing (0.05%-0.12 wt.%) ***-scale heats and pilot rolling trials simulating air and water-cooled plate production as well as hot-rolled strip production were made and the effects of C,Mn,Ni,Cu,Cr,Mo,Nb,Ti and b on transformation characteristics and temperatures of recrystallisation *** equations for the characterisation of microstructure,tensile and impact properties and for the weldability of these steels were *** were manufactured and processed into plate and coil-plate by three steel companies and pipe produced from both *** from these,plus thicker plate for structural use,were determined and these compared well with the values predicted from the regression *** project has shown that excellent combinations of strength,toughness and weldability can be obtained for a wide variety of *** benefits were seen and recommendations on altering the limits for niobium in Euronorms have been proposed.

关键词： steel niobium linepipe structural property

Does disruptive camouflage conceal edges and features？

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Current Zoology 2015年第4期61卷 708-717页

作者： Richard J. webster Department of biology Carleton University Ottawa K1S 5B6 Canada

Camouflage is ubiquitous in the natural world and benefits both predators and prey. Amongst the range of conceal- ment strategies, disruptive coloration is thought to visually fragment an animal＇s＇ outline, thereby reducing its rate of discovery. Here, I propose two non-mutually exclusive hypotheses for how disruptive camouflage functions, and describe the visual me- chanisms that might underlie them. （1） The local edge disruption hypothesis states that camouflage is achieved by breaking up edge information. （2） The global feature disruption hypothesis states camouflage is achieved by breaking up the characteristic features of an animal （e.g., overall shape or facial features）. Research clearly shows that putatively disruptive edge markings do increase concealment; however, few tests have been undertaken to determine whether this survival advantage is attributable to the distortion of features, so the global feature disruption hypothesis is under studied. In this review the evidence for global feature disruption is evaluated. Further, I address if object recognition processing provides a feasible mechanism for animals＇ features to influence concealment. This review concludes that additional studies are needed to test if disruptive camouflage operates through the global feature disruption and proposes future research directions [Current Zoology 61 （4）： 708-717, 2015].

关键词： Antipredator background matching Contour Crypsis Camouflage Disruptive coloration Edge detection Objectrecognition

Therapeutic resistance in cancer: microRNA regulation of EGFR signaling networks

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Cancer biology & Medicine 2013年第4期10卷 192-205页

作者： German G.Gomez Jill Wykosky Ciro Zanca Frank b.Furnari webster K.Cavenee Ludwig Institute for Cancer Research University of California San Diego

Receptor tyrosine kinases(RTKs)such as the epidermal growth factor receptor(EGFR)regulate cellular homeostatic *** activates downstream signaling cascades that promote tumor cell survival,proliferation and *** of EGFR signaling as a consequence of overexpression,amplification and mutation of the EGFR gene occurs frequently in several types of cancers and many become dependent on EGFR signaling to maintain their malignant ***,concerted efforts have been mounted to develop therapeutic agents and strategies to effectively inhibit ***,limited therapeutic benefits to cancer patients have been derived from EGFR-targeted therapies.A well-documented obstacle to improved patient survival is the presence of EGFR-inhibitor resistant tumor cell variants within heterogeneous tumor cell ***,we summarize the mechanisms by which tumors resist EGFR-targeted therapies and highlight the emerging role of microRNAs(miRs)as downstream effector molecules utilized by EGFR to promote tumor initiation,progression and that play a role in resistance to EGFR *** also examine evidence supporting the utility of miRs as predictors of response to targeted therapies and novel therapeutic agents to circumvent EGFR-inhibitor resistance mechanisms.

关键词： Epidermal growth factor receptor microRNA tyrosine kinase inhibitors therapeutic resistance

The redshift distribution of bL Lacs and FSRQs

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Research in Astronomy and Astrophysics 2019年第1期19卷 131-140页

作者： David Garofalo Chandra b.Singh Dylan T.Walsh Damian J.Christian Andrew M.Jones Alexa Zack brandt webster Matthew I.Kim Department of Physics Kennesaw State University The Raymond and beverly Sackler School of Physics and Astronomy Tel Aviv University Department of Physics & Astronomy California State University boise State University Computational Science & Engineering

Flat spectrum radio quasars(FSRQs) and bL Lacertae objects(bL Lacs) are powerful jet producing active galactic nuclei associated with supermassive black holes accreting at high and low Eddington rates, respectively. based on the Millennium Simulation, Gardner & Done have predicted their redshift distribution by appealing to ideas from the spin paradigm in a way that exposes a need for a deeper discussion on three interrelated issues:(1) an overprediction of bL Lacs compared to FSRQs;(2) a difference in FSRQ and bL Lac distributions;(3) a need for powerful but different jets at separated cosmic times. beginning with Gardner & Done's determination of Fermi observable FSRQs based on the distribution of thermal accretion across cosmic time from the Millennium Simulation, we connect FSRQs to bL Lacs by way of the gap paradigm for black hole accretion and jet formation to address the above issues in a unified way. We identify a physical constraint in the paradigm for the numbers of bL Lacs that naturally leads to separate peaks in time for different albeit powerful jets. In addition, we both identify as puzzling and ascribe physical significance to a tail end in the bL Lac curve versus redshift that is unseen in the redshift distribution for FSRQs.

关键词： black hole physics bL Lacertae objects:general galaxies:ets gamma-rays:galaxies

Endocrine correlates of mate choice and promiscuity in females of a socially monogamous avian mating system with alternative male reproductive phenotypes

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Current Zoology 2014年第6期60卷 804-815页

作者： Hubert SCHWAbL Willow R. LINDSAY Douglas G. bARRON Michael S. webster School of biological Sciences and Center for Reproductive biology Washington State University Pullman WA 99164-4236 USA Department of Department of biological and Environmental Sciences Goteborg University Box 463405 30 Goteborg Sweden Department of Psychology University of South Florida Tampa FL 33620-7200 USA Department of Neurobiology and behavior and Comell Laboratory for Ornithology Comell University Ithaca NY 14850 USA

While our understanding of male reproductive strategies is informed by extensive investigations into endocrine mechanisms, the proximate mechanisms by which females compete for mates and adjust reproduction to social environment remains enigmatic. We set out to uncover endocrine correlates of mate choice, social environment, and reproductive investment in female red-backed fairy-wrens Malurus melanocephalus. In this socially monogamous, yet highly sexually promiscuous species, females experience discrete variation in the phenotype of their mates, which vary in both plumage signals and level of paternal care, and in the composition of their breeding groups, which consist of either the pair alone or with an additional cooperative auxiliary; fe- male investment varies according to these social parameters. We found that androgen, estrogen, and glucorticoid levels varied with reproductive stage, with highest androgen and estrogen concentrations during nest construction and highest corticosterone concentrations during the pre-breeding stage. These stage-dependent patterns did not vary with male phenotype or auxiliary presence, though androgen levels during pre-breeding mate selection were lower in females obtaining red/black mates than those obtaining brown mates. We found no evidence that androgen, estrogen, or corticosterone levels during the fertile period were re- lated to extra-pair young （EPY） frequency. This study demonstrates clear changes in steroid levels with reproductive stage, though it found little support for variation with social environment. We suggest hormonal responsiveness to social factors may be physiologically constrained in ways that are bypassed through exogenous hormone manipulations.

关键词： Androgen Estrogen Glucocorticoid Mate choice Promiscuity Alternative phenotypes

Fundamental motor skills,screen-time,and physical activity in preschoolers

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Journal of Sport and Health Science 2019年第2期8卷 114-121页

作者： E.Kipling webster Corby K.Martin Amanda E.Staiano School ofKinesiology Louisiana State University Pennington biomedical Research Center Louisiana State University

Purpose: To examine the associations among preschoolers fundamental motor skills, screen-time, physical activity(PA), and sedentary behavior(Sb).Methods: Children ages 3à4 years were enrolled in a prospective observational trial of PA. Trained assessors conducted the Test of Gross Motor Development-3 rd edition(TGMD-3), and the Movement Assessment battery for Children-2 nd edition, and parent-reported child screen-time and sociodemographic information. Children wore an accelerometer for 7 days to examine Sb and total PA(TPA). TPA was further characterized as moderateto-vigorous PA(MVPA) or vigorous PA(VPA). Mixed linear models were calculated, controlling for age(for TGMD-3), sex, household income, and accelerometer wear time(for accelerometry models), with childcare center as a random effect. The primary analysis reported on the cross-sectional baseline data of 126 children with complete fundamental motor skill and screen-time data; a subanalysis included 88 children with complete accelerometry ***: Children were 3.4 § 0.5 years of age(54% girls; 46% white, 42% African American, 12% other). A total of 48% lived in households at or below the federal poverty level. Children engaged in 5.1 § 3.6 h/day of screen-time. Children's screen-time was inversely related to the Movement Assessment battery for Children-2 nd edition, manual dexterity skills percentile(b(SE) = ?1.7(0.8), p = 0.049). In the accelerometry subsample,children engaged in 5.9 § 0.9 h/day of TPA of which 1.7 § 0.6 h/day was MVPA. boys engaged in more MVPA and VPA and less Sb compared with girls(all p b(SE) = 0.4(0.2), p = 0.017) and locomotor score(b(SE) = 0.7(0.3), p = 0.018) were associated with more VPA but not with TPA or MVPA. Screen-time and television in the bedroom were not related to Sb, TPA, MVPA, or ***: Children's motor skills were positively related to VPA but inversely related to screen-time. Further inquiry into the implications of

关键词： Fundamental motor skills Physical activity Preschool Screen-time

Green-Naghdi Theory,Part A:Green-Naghdi(GN) Equations for Shallow Water Waves

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Journal of Marine Science and Application 2011年第3期10卷 253-258页

作者： William C. webster Wenyang Duan binbin Zhao Department of Civil ＆ Environmental Engineering University of California Berkeley CA 94720-1710 USA College of Shipbuilding Engineering Harbin Engineering University 150001 Harbin China

In this work, Green-Naghdi （GN） equations with general weight functions were derived in a simple way. A wave-absorbing beach was also considered in the general GN equations. A numerical solution for a level higher than 4 was not feasible in the past with the original GN equations. The GN equations for shallow water waves were simplified here, which make the application of high level （higher than 4） equations feasible. The linear dispersion relationships of the first seven levels were presented. The accuracy of dispersion relationships increased as the level increased. Level 7 GN equations are capable of simulating waves out to wave number times depth kd 〈 26. Numerical simulation of nonlinear water waves was performed by use of Level 5 and 7 GN equations, which will be presented in the next paper.

关键词： Green-Naghdi (GN) equations dispersion relation wave-absorbing beach shallow-water waves

教育过程中的计算机培训和对计算机的忧虑一项试验分析

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计算机工程与应用 1991年第5期27卷 148-161页

作者： J.webster J.b.Heian 莫春雷国家教委信息中心

八十年代,教育机构和其它部门普遍引入了微机技术。在培训方法和个人因素(如对计算机的忧虑)的双重作用下,微机软件培训已经取得了多项成果。本项研究的课题为软件培训,提出了两项研究的结果。第一项研究论证了测度计算机忧虑的方法;接... 详细信息

八十年代,教育机构和其它部门普遍引入了微机技术。在培训方法和个人因素(如对计算机的忧虑)的双重作用下,微机软件培训已经取得了多项成果。本项研究的课题为软件培训,提出了两项研究的结果。第一项研究论证了测度计算机忧虑的方法;接着的第二项研究对比了培训方法和计算机忧虑二者对培训成果产生的影响,证明了培训方法与培训成果的关系要强于计算机忧虑与培训成果的关系。另外,第二项研究还比较了两种培训方法,发现与称为“工作”的培训相比,“玩”培训会更有利于取得培训成果。

关键词：教育计算机培训