Science.gov

Sample records for effective resistance metric

  1. Resisting anchoring effects: The roles of metric and mapping knowledge.

    PubMed

    Smith, Andrew R; Windschitl, Paul D

    2015-10-01

    The biasing influence of anchors on numerical estimates is well established, but the relationship between knowledge level and the susceptibility to anchoring effects is less clear. In two studies, we addressed the potential mitigating effects of having knowledge in a domain on vulnerability to anchoring effects in that domain. Of critical interest was a distinction between two forms of knowledge-metric and mapping knowledge. In Study 1, participants who had studied question-relevant information-that is, high-knowledge participants-were less influenced by anchors than were participants who had studied irrelevant information. The results from knowledge measures suggested that the reduction in anchoring was tied to increases in metric rather than mapping knowledge. In Study 2, participants studied information specifically designed to influence different types of knowledge. As we predicted, increases in metric knowledge-and not mapping knowledge-led to reduced anchoring effects. Implications for debiasing anchoring effects are discussed.

  2. Comparison of mixed effects models of antimicrobial resistance metrics of livestock and poultry Salmonella isolates from a national monitoring system.

    PubMed

    Bjork, K E; Kopral, C A; Wagner, B A; Dargatz, D A

    2015-12-01

    Antimicrobial use in agriculture is considered a pathway for the selection and dissemination of resistance determinants among animal and human populations. From 1997 through 2003 the U.S. National Antimicrobial Resistance Monitoring System (NARMS) tested clinical Salmonella isolates from multiple animal and environmental sources throughout the United States for resistance to panels of 16-19 antimicrobials. In this study we applied two mixed effects models, the generalized linear mixed model (GLMM) and accelerated failure time frailty (AFT-frailty) model, to susceptible/resistant and interval-censored minimum inhibitory concentration (MIC) metrics, respectively, from Salmonella enterica subspecies enterica serovar Typhimurium isolates from livestock and poultry. Objectives were to compare characteristics of the two models and to examine the effects of time, species, and multidrug resistance (MDR) on the resistance of isolates to individual antimicrobials, as revealed by the models. Fixed effects were year of sample collection, isolate source species and MDR indicators; laboratory study site was included as a random effect. MDR indicators were significant for every antimicrobial and were dominant effects in multivariable models. Temporal trends and source species influences varied by antimicrobial. In GLMMs, the intra-class correlation coefficient ranged up to 0.8, indicating that the proportion of variance accounted for by laboratory study site could be high. AFT models tended to be more sensitive, detecting more curvilinear temporal trends and species differences; however, high levels of left- or right-censoring made some models unstable and results uninterpretable. Results from GLMMs may be biased by cutoff criteria used to collapse MIC data into binary categories, and may miss signaling important trends or shifts if the series of antibiotic dilutions tested does not span a resistance threshold. Our findings demonstrate the challenges of measuring the AMR

  3. Toward an ozone standard to protect vegetation based on effective dose: A review of deposition resistances and a possible metric

    Treesearch

    W. J. Massman

    2004-01-01

    Present air quality standards to protect vegetation from ozone are based on measured concentrations (i.e., exposure) rather than on plant uptake rates (or dose). Some familiar cumulative exposure-based indices include SUM06, AOT40, and W126. However, plant injury is more closely related to dose, or more appropriately to effective dose, than to exposure. This study...

  4. Inspecting baby Skyrmions with effective metrics

    NASA Astrophysics Data System (ADS)

    Gibbons, G. W.; Goulart, E.

    2014-05-01

    In the present paper we investigate the causal structure of the baby Skyrme model using appropriate geometrical tools. We discuss several features of excitations propagating on top of background solutions and show that the evolution of high frequency waves is governed by a curved effective geometry. Examples are given for which the effective metric describes the interaction between waves and solitonic solutions such as kinks, antikinks, and hedgehogs. In particular, it is shown how violent processes involving the collisions of solitons and antisolitons may induce metrics which are not globally hyperbolic. We argue that it might be illuminating to calculate the effective metric as a diagnostic test for pathological regimes in numerical simulations.

  5. Effectively nonlocal metric-affine gravity

    NASA Astrophysics Data System (ADS)

    Golovnev, Alexey; Koivisto, Tomi; Sandstad, Marit

    2016-03-01

    In metric-affine theories of gravity such as the C-theories, the spacetime connection is associated to a metric that is nontrivially related to the physical metric. In this article, such theories are rewritten in terms of a single metric, and it is shown that they can be recast as effectively nonlocal gravity. With some assumptions, known ghost-free theories with nonsingular and cosmologically interesting properties may be recovered. Relations between different formulations are analyzed at both perturbative and nonperturbative levels, taking carefully into account subtleties with boundary conditions in the presence of integral operators in the action, and equivalences between theories related by nonlocal redefinitions of the fields are verified at the level of equations of motion. This suggests a possible geometrical interpretation of nonlocal gravity as an emergent property of non-Riemannian spacetime structure.

  6. An Attentional Effect of Musical Metrical Structure

    PubMed Central

    Katz, Jonah; Chemla, Emmanuel; Pallier, Christophe

    2015-01-01

    Theories of metrical structure postulate the existence of several degrees of beat strength. While previous work has clearly established that humans are sensitive to the distinction between strong beats and weak ones, there is little evidence for a more fine grained distinction between intermediate levels. Here, we present experimental data showing that attention can be allocated to an intermediate level of beat strength. Comparing the effects of short exposures to 6/8 and 3/4 metrical structures on a tone detection task, we observe that subjects respond differently to beats of intermediate strength than to weak beats. PMID:26600180

  7. Metrics. [measurement for effective software development and management

    NASA Technical Reports Server (NTRS)

    Mcgarry, Frank

    1991-01-01

    A development status evaluation is presented for practical software performance measurement, or 'metrics', in which major innovations have recently occurred. Metrics address such aspects of software performance as whether a software project is on schedule, how many errors can be expected from it, whether the methodology being used is effective and the relative quality of the software employed. Metrics may be characterized as explicit, analytical, and subjective. Attention is given to the bases for standards and the conduct of metrics research.

  8. Quantum Hall Effect and Quillen Metric

    NASA Astrophysics Data System (ADS)

    Klevtsov, Semyon; Ma, Xiaonan; Marinescu, George; Wiegmann, Paul

    2017-02-01

    We study the generating functional, the adiabatic curvature and the adiabatic phase for the integer quantum Hall effect (QHE) on a compact Riemann surface. For the generating functional we derive its asymptotic expansion for the large flux of the magnetic field, i.e., for the large degree k of the positive Hermitian line bundle L k . The expansion consists of the anomalous and exact terms. The anomalous terms are the leading terms of the expansion. This part is responsible for the quantization of the adiabatic transport coefficients in QHE. We then identify the non-local (anomalous) part of the expansion with the Quillen metric on the determinant line bundle, and the subleading exact part with the asymptotics of the regularized spectral determinant of the Laplacian for the line bundle L k , at large k. Finally, we show how the generating functional of the integer QHE is related to the gauge and gravitational (2+1)d Chern-Simons functionals. We observe the relation between the Bismut-Gillet-Soulé curvature formula for the Quillen metric and the adiabatic curvature for the electromagnetic and geometric adiabatic transport of the integer Quantum Hall state. We then obtain the geometric part of the adiabatic phase in QHE, given by the Chern-Simons functional.

  9. Comparative study of line roughness metrics of chemically amplified and inorganic resists for EUV

    NASA Astrophysics Data System (ADS)

    Fallica, Roberto; Buitrago, Elizabeth; Ekinci, Yasin

    2016-03-01

    We present a comprehensive study of the roughness metrics of different resists. Dense line/space (L/S) images of polymethyl methacrylate (PMMA), hydrogen silsesquioxane (HSQ), different chemically amplified resists (CARs), and metal oxide based resists have been patterned by extreme ultraviolet interference lithography (EUV-IL). The three line width roughness metrics: r.m.s. value σLWR, correlation length ξ and roughness exponent α, were measured by metrological analysis of top down SEM images and compared for the different resists imaged here. It was found, that all metrics are required to fully describe the roughness of each resist. Our measurements indicate that few of the state-of-the- art resists tested here can meet the International Technology Roadmap for Semiconductors (ITRS) requirements for σLWR. The correlation length ξ has been found to be considerably higher in polymer-based materials in comparison to non-polymers. The roughness exponent α, interpreted using the concept of fractal geometry, is mainly affected by acid diffusion in CARs where it produces line edges with a higher complexity than in non-CAR resists. These results indicate that different resists platforms show very different LWR resist metrics and roughness is not only manifested in the σLWR but in all parameters. Therefore, all roughness metrics should be taken into account in the performance comparison of the resist, since they can have a substantial impact on the device performance.

  10. Comparative study of line roughness metrics of chemically amplified and inorganic resists for extreme ultraviolet

    NASA Astrophysics Data System (ADS)

    Fallica, Roberto; Buitrago, Elizabeth; Ekinci, Yasin

    2016-07-01

    We present a comprehensive comparative study of the roughness metrics of different resists. Dense line/space of polymethyl methacrylate, hydrogen silsesquioxane, a metal oxide-based resist, and different chemically amplified resists (CARs) have been patterned by extreme ultraviolet interference lithography. All three line width roughness (LWR) metrics: the root-mean-square (r.m.s.) roughness value σLWR, the correlation length ξ, and the roughness exponent α, were extracted by metrological analysis of top-down SEM images. We found that all metrics are required to fully describe the overall roughness of each resist. Our measurements indicate that in fact, a few of the state-of-the-art resists tested here can meet the International Technology Roadmap for Semiconductors requirements for σLWR. The correlation length ξ was also found to be considerably higher in polymer-based materials in comparison to nonpolymers. Finally, the roughness exponent α, interpreted using the concept of fractal geometry, was found to be mainly affected by acid diffusion in CARs, where it produces line edges with a higher complexity than in non-CAR resists. These results indicate that the different resists platforms show very different LWR metrics and roughness is not manifested only in the σLWR but in all parameters. Therefore, all roughness metrics should be taken into account when comparing the performance among different resists since they ultimately have a substantial impact on device performance.

  11. Coverage Metrics for Requirements-Based Testing: Evaluation of Effectiveness

    NASA Technical Reports Server (NTRS)

    Staats, Matt; Whalen, Michael W.; Heindahl, Mats P. E.; Rajan, Ajitha

    2010-01-01

    In black-box testing, the tester creates a set of tests to exercise a system under test without regard to the internal structure of the system. Generally, no objective metric is used to measure the adequacy of black-box tests. In recent work, we have proposed three requirements coverage metrics, allowing testers to objectively measure the adequacy of a black-box test suite with respect to a set of requirements formalized as Linear Temporal Logic (LTL) properties. In this report, we evaluate the effectiveness of these coverage metrics with respect to fault finding. Specifically, we conduct an empirical study to investigate two questions: (1) do test suites satisfying a requirements coverage metric provide better fault finding than randomly generated test suites of approximately the same size?, and (2) do test suites satisfying a more rigorous requirements coverage metric provide better fault finding than test suites satisfying a less rigorous requirements coverage metric? Our results indicate (1) only one coverage metric proposed -- Unique First Cause (UFC) coverage -- is sufficiently rigorous to ensure test suites satisfying the metric outperform randomly generated test suites of similar size and (2) that test suites satisfying more rigorous coverage metrics provide better fault finding than test suites satisfying less rigorous coverage metrics.

  12. Operational sustainability metrics assessing metric effectiveness in the context of electronics-recycling systems.

    PubMed

    Atlee, Jennifer; Kirchain, Randolph

    2006-07-15

    In the past 15 years corporations and governments have developed a growing appreciation of the need for sustainability. However, there is still little clarity on how to move toward the goal of sustainability or measure improvements. Not only are there currently few operational metrics by which to practically assess progress toward sustainability, there is also little understanding of how to judge the effectiveness of such metrics. This paper presents a pragmatic approach to developing--and evaluating--system-specific performance metrics for sustainability. Electronics recycling is used as a case problem in developing and judging the effectiveness of such metrics. Despite growing concerns aboutthe handling of end-of-life electronics, data availability is inconsistent, and there is still limited understanding of the electronics-recycling system as a whole. To begin to address the need for practical quantitative methods to assess system performance, several indicators were developed and applied to three U.S. electronics-recycling operations. These metrics were assessed based on the developed criteria that effective measures be useful, robust, and feasible. Results show that the current measure of "mass percent to landfill" is not sufficient to assess system performance. Relevance-weighted mass indicators with varying data requirements can provide additional insights on resource efficiency.

  13. An unbiased metric of antiproliferative drug effect in vitro

    PubMed Central

    Harris, Leonard A.; Frick, Peter L.; Garbett, Shawn P.; Hardeman, Keisha N.; Paudel, B. Bishal; Lopez, Carlos F.; Quaranta, Vito; Tyson, Darren R.

    2016-01-01

    In vitro cell proliferation assays are widely used in pharmacology, molecular biology, and drug discovery. Using theoretical modeling and experimentation, we show that current antiproliferative drug effect metrics suffer from time-dependent bias, leading to inaccurate assessments of parameters such as drug potency and efficacy. We propose the drug-induced proliferation (DIP) rate, the slope of the line on a plot of cell population doublings versus time, as an alternative, time-independent metric. PMID:27135974

  14. Effective coverage: a metric for monitoring Universal Health Coverage.

    PubMed

    Ng, Marie; Fullman, Nancy; Dieleman, Joseph L; Flaxman, Abraham D; Murray, Christopher J L; Lim, Stephen S

    2014-09-01

    A major challenge in monitoring universal health coverage (UHC) is identifying an indicator that can adequately capture the multiple components underlying the UHC initiative. Effective coverage, which unites individual and intervention characteristics into a single metric, offers a direct and flexible means to measure health system performance at different levels. We view effective coverage as a relevant and actionable metric for tracking progress towards achieving UHC. In this paper, we review the concept of effective coverage and delineate the three components of the metric - need, use, and quality - using several examples. Further, we explain how the metric can be used for monitoring interventions at both local and global levels. We also discuss the ways that current health information systems can support generating estimates of effective coverage. We conclude by recognizing some of the challenges associated with producing estimates of effective coverage. Despite these challenges, effective coverage is a powerful metric that can provide a more nuanced understanding of whether, and how well, a health system is delivering services to its populations.

  15. Joint allelic effects on fitness and metric traits.

    PubMed

    McGuigan, Katrina; Blows, Mark W

    2013-04-01

    Theoretical explanations of empirically observed standing genetic variation, mutation, and selection suggest that many alleles must jointly affect fitness and metric traits. However, there are few direct demonstrations of the nature and extent of these pleiotropic associations. We implemented a mutation accumulation (MA) divergence experimental design in Drosophila serrata to segregate genetic variants for fitness and metric traits. By exploiting naturally occurring MA line extinctions as a measure of line-level total fitness, manipulating sexual selection, and measuring productivity we were able to demonstrate genetic covariance between fitness and standard metric traits, wing size, and shape. Larger size was associated with lower total fitness and male sexual fitness, but higher productivity. Multivariate wing shape traits, capturing major axes of wing shape variation among MA lines, evolved only in the absence of sexual selection, and to the greatest extent in lines that went extinct, indicating that mutations contributing wing shape variation also typically had deleterious effects on both total fitness and male sexual fitness. This pleiotropic covariance of metric traits with fitness will drive their evolution, and generate the appearance of selection on the metric traits even in the absence of a direct contribution to fitness.

  16. Defining Attributes and Metrics of Effective Research Mentoring Relationships

    PubMed Central

    Byars-Winston, Angela; Branchaw, Janet; Hurtado, Sylvia; Eagan, Kevin

    2016-01-01

    Despite evidence of mentoring’s importance in training researchers, studies to date have not yet determined which mentoring relationships have the most impact and what specific factors in those mentoring relationships contribute to key outcomes, such as the commitment to and persistence in research career paths for emerging researchers from diverse populations. Efforts to broaden participation and persistence in biomedical research careers require an understanding of why and how mentoring relationships work and their impact, not only to research training but also to promoting career advancement. This paper proposes core attributes of effective mentoring relationships, as supported by the literature and suggested by theoretical models of academic persistence. In addition, both existing and developing metrics for measuring the effectiveness of these attributes within mentoring relationships across diverse groups are presented, as well as preliminary data on these metrics from the authors’ work. PMID:27062425

  17. Defining Attributes and Metrics of Effective Research Mentoring Relationships.

    PubMed

    Pfund, Christine; Byars-Winston, Angela; Branchaw, Janet; Hurtado, Sylvia; Eagan, Kevin

    2016-09-01

    Despite evidence of mentoring's importance in training researchers, studies to date have not yet determined which mentoring relationships have the most impact and what specific factors in those mentoring relationships contribute to key outcomes, such as the commitment to and persistence in research career paths for emerging researchers from diverse populations. Efforts to broaden participation and persistence in biomedical research careers require an understanding of why and how mentoring relationships work and their impact, not only to research training but also to promoting career advancement. This paper proposes core attributes of effective mentoring relationships, as supported by the literature and suggested by theoretical models of academic persistence. In addition, both existing and developing metrics for measuring the effectiveness of these attributes within mentoring relationships across diverse groups are presented, as well as preliminary data on these metrics from the authors' work.

  18. The quest for the best metric of antibiotic use and its correlation with the emergence of fluoroquinolone resistance in children.

    PubMed

    Rose, Lucia; Coulter, Marissa M; Chan, Shannon; Hossain, Jobayer; Di Pentima, M Cecilia

    2014-06-01

    We evaluated the correlation between fluoroquinolone use, measured by doses administered and days of therapy, with the emergence of ciprofloxacin and levofloxacin resistance among Gram-negative bacilli infections in children hospitalized at one pediatric center between April 2001 and March 2009. Both metrics and drug resistance were highly correlated.

  19. Effects of Metric Change on Workers’ Tools and Training.

    DTIC Science & Technology

    1981-07-01

    hydraulic systems . However, no experiential data were available on this issue. In most cases, discussions of productivity led to the conclusion that...1975 (P.L. 94-168), the U.S. Congress established a nationil policy of planning and coordinat- ing the increasing voluntary us, of the metric system ...It also established the U.S. Metric Board to plao and coordinate voluntary conversions to the metric system . The U.S. Metric Board has been directed by

  20. Effects of subsampling of passive acoustic recordings on acoustic metrics.

    PubMed

    Thomisch, Karolin; Boebel, Olaf; Zitterbart, Daniel P; Samaran, Flore; Van Parijs, Sofie; Van Opzeeland, Ilse

    2015-07-01

    Passive acoustic monitoring is an important tool in marine mammal studies. However, logistics and finances frequently constrain the number and servicing schedules of acoustic recorders, requiring a trade-off between deployment periods and sampling continuity, i.e., the implementation of a subsampling scheme. Optimizing such schemes to each project's specific research questions is desirable. This study investigates the impact of subsampling on the accuracy of two common metrics, acoustic presence and call rate, for different vocalization patterns (regimes) of baleen whales: (1) variable vocal activity, (2) vocalizations organized in song bouts, and (3) vocal activity with diel patterns. To this end, above metrics are compared for continuous and subsampled data subject to different sampling strategies, covering duty cycles between 50% and 2%. The results show that a reduction of the duty cycle impacts negatively on the accuracy of both acoustic presence and call rate estimates. For a given duty cycle, frequent short listening periods improve accuracy of daily acoustic presence estimates over few long listening periods. Overall, subsampling effects are most pronounced for low and/or temporally clustered vocal activity. These findings illustrate the importance of informed decisions when applying subsampling strategies to passive acoustic recordings or analyses for a given target species.

  1. Defining New Metrics in Microwave Ablation of Pulmonary Tumors: Ablation Work and Ablation Resistance Score.

    PubMed

    Al-Hakim, Ramsey A; Abtin, Fereidoun G; Genshaft, Scott J; Kutay, Erin; Suh, Robert D

    2016-09-01

    To investigate pulmonary microwave ablation metrics including ablation work, ablation resistance score, and involution. Retrospective review was performed of 98 pulmonary tumor ablations using the NeuWave Certus Microwave Ablation System (NeuWave Medical, Madison, Wisconsin) in 71 patients (32 men and 39 women; mean age, 64.7 y ± 11.5). Ablation work was defined as sum of (power) * (time) * (number of antennas) for all phases during an ablation procedure. Ablation zone was measured on CT at 3 time points: after procedure, 1-3 months (mean 47 d), and 3-12 months (mean 292 d). Ablation zones were scored based on location for pulmonary lobe (upper = 1, middle/lingula = 2, lower = 3) and region (peripheral = 1, parenchymal = 2, central = 3), and the 2 were summed for ablation resistance score. Ablation zone on CT at 1-3 months was significantly smaller in regions with higher ablation resistance score (P < .05). There was a significant correlation between ablation work and ablation zone measured on CT performed after procedure (P < .001), at 1-3 months (P < .001), and at 3-12 months (P < .05). Ablation zone significantly decreased from after procedure to 1-3 months (P < .001) and from 1-3 months to 3-12 months (P < .001), with change from after procedure to 1-3 months significantly greater (P < .01). Pulmonary microwave ablation zone is significantly smaller in regions with higher ablation resistance score. Ablation work correlates to ablation zone with a nonlinear involution pattern in the first year and may be useful for planning before the procedure. Copyright © 2016 SIR. Published by Elsevier Inc. All rights reserved.

  2. Effects of quantum fluctuations of metric on the universe

    NASA Astrophysics Data System (ADS)

    Yang, Rongjia

    2016-09-01

    We consider a model of modified gravity from the nonperturbative quantization of a metric. We obtain the modified gravitational field equations and the modified conservational equations. We apply it to the FLRW spacetime and find that due to the quantum fluctuations a bounce universe can be obtained and a decelerated expansion can also possibly be obtained in a dark energy dominated epoch. We also discuss the effects of quantum fluctuations on inflation parameters (such as slow-roll parameters, spectral index, and the spectrum of the primordial curvature perturbation) and find values of parameters in the comparing the predictions of inflation can also work to drive the current epoch of acceleration. We obtain the constraints on the parameter of the theory from the observation of the big bang nucleosynthesis.

  3. The effect of measurement error on surveillance metrics

    SciTech Connect

    Weaver, Brian Phillip; Hamada, Michael S.

    2012-04-24

    The purpose of this manuscript is to describe different simulation studies that CCS-6 has performed for the purpose of understanding the effects of measurement error on the surveillance metrics. We assume that the measured items come from a larger population of items. We denote the random variable associate with an item's value of an attribute of interest as X and that X {approx} N({mu}, {sigma}{sup 2}). This distribution represents the variability in the population of interest and we wish to make inference on the parameters {mu} and {sigma} or on some function of these parameters. When an item X is selected from the larger population, a measurement is made on some attribute of it. This measurement is made with error and the true value of X is not observed. The rest of this section presents simulation results for different measurement cases encountered.

  4. Metrics and the effective computational scientist: process, quality and communication.

    PubMed

    Baldwin, Eric T

    2012-09-01

    Recent treatments of computational knowledge worker productivity have focused upon the value the discipline brings to drug discovery using positive anecdotes. While this big picture approach provides important validation of the contributions of these knowledge workers, the impact accounts do not provide the granular detail that can help individuals and teams perform better. I suggest balancing the impact-focus with quantitative measures that can inform the development of scientists. Measuring the quality of work, analyzing and improving processes, and the critical evaluation of communication can provide immediate performance feedback. The introduction of quantitative measures can complement the longer term reporting of impacts on drug discovery. These metric data can document effectiveness trends and can provide a stronger foundation for the impact dialogue. Copyright © 2012 Elsevier Ltd. All rights reserved.

  5. Effecting IT infrastructure culture change: management by processes and metrics

    NASA Technical Reports Server (NTRS)

    Miller, R. L.

    2001-01-01

    This talk describes the processes and metrics used by Jet Propulsion Laboratory to bring about the required IT infrastructure culture change to update and certify, as Y2K compliant, thousands of computers and millions of lines of code.

  6. Effecting IT infrastructure culture change: management by processes and metrics

    NASA Technical Reports Server (NTRS)

    Miller, R. L.

    2001-01-01

    This talk describes the processes and metrics used by Jet Propulsion Laboratory to bring about the required IT infrastructure culture change to update and certify, as Y2K compliant, thousands of computers and millions of lines of code.

  7. Network Metamodeling: The Effect of Correlation Metric Choice on Phylogenomic and Transcriptomic Network Topology

    SciTech Connect

    Weighill, Deborah A; Jacobson, Daniel A

    2017-01-01

    We explore the use of a network meta-modeling approach to compare the effects of similarity metrics used to construct biological networks on the topology of the resulting networks. This work reviews various similarity metrics for the construction of networks and various topology measures for the characterization of resulting network topology, demonstrating the use of these metrics in the construction and comparison of phylogenomic and transcriptomic networks.

  8. Network Metamodeling: Effect of Correlation Metric Choice on Phylogenomic and Transcriptomic Network Topology.

    PubMed

    Weighill, Deborah A; Jacobson, Daniel

    2017-01-10

    We explore the use of a network meta-modeling approach to compare the effects of similarity metrics used to construct biological networks on the topology of the resulting networks. This work reviews various similarity metrics for the construction of networks and various topology measures for the characterization of resulting network topology, demonstrating the use of these metrics in the construction and comparison of phylogenomic and transcriptomic networks.

  9. Effective use of metrics in an ALARA program

    SciTech Connect

    Bates, B.B. Jr.

    1996-07-01

    ALARA radiological protection programs require metrics to meet their objectives. Sources of metrics include; external dosimetry; internal dosimetry; radiological occurrences from the occurrence reporting and processing system (ORPS); and radiological incident reports (RIR). The sources themselves contain an abundance of specific ``indicators``. To choose the site-specific indicators that will be tracked and trended requires careful review. This required the end users to expend valuable time and effort to locate the data they needed. To address this problem, a central metrics database has been developed so that customers can have all their questions addressed quickly and correctly. The database was developed in the beginning to answer some of the customer`s most frequently asked questions. It is now also a tool to communicate the status of the radiation protection program to facility managers. Finally it also addresses requirements contained in the Rad Con manual and the 10CFR835 implementation guides. The database uses currently available, ``user friendly``, software and contains information from RIR`s, ORPS, and external dosimetry records specific to ALARA performance indicators. The database is expandable to allow new metrics input. Specific reports have been developed to assist customers in their tracking and trending of ALARA metrics.

  10. Making Metrics Matter: How to Use Indicators to Govern Effectively

    ERIC Educational Resources Information Center

    Allen, Clyde; Bacow, Lawrence S.; Trombley, Laura Skandera

    2011-01-01

    Many institutions develop specific measures or indicators--often called "dashboards"--to inform boards and top administrators about the college or university's current situation and performance and assist them in moving the institution ahead strategically. And, increasingly, institutions are using metrics not only to assess internal…

  11. Development of Metrics to Evaluate Effectiveness of Emergency Response Operations

    DTIC Science & Technology

    2005-06-01

    00-00-2005 4. TITLE AND SUBTITLE Development of Metrics to Evaluate Efectiveness of Emergency Response Operations 5a. CONTRACT NUMBER 5b. GRANT...population and/or property. Furthermore, the disaster will be characterized as being large enough that the resources the community has to mitigate the...disaster are stretched beyond the limits of their capacity. Such events that a community can readily cope with, such as small fires, individual

  12. Think Metric

    USGS Publications Warehouse

    ,

    1978-01-01

    The International System of Units, as the metric system is officially called, provides for a single "language" to describe weights and measures over the world. We in the United States together with the people of Brunei, Burma, and Yemen are the only ones who have not put this convenient system into effect. In the passage of the Metric Conversion Act of 1975, Congress determined that we also will adopt it, but the transition will be voluntary.

  13. Wave-packet dynamics of Bogoliubov quasiparticles: Quantum metric effects

    NASA Astrophysics Data System (ADS)

    Liang, Long; Peotta, Sebastiano; Harju, Ari; Törmä, Päivi

    2017-08-01

    We study the dynamics of the Bogoliubov wave packet in superconductors and calculate the supercurrent carried by the wave packet. We discover an anomalous contribution to the supercurrent, related to the quantum metric of the Bloch wave function. This anomalous contribution is most important for flat or quasiflat bands, as exemplified by the attractive Hubbard models on the Creutz ladder and sawtooth lattice. Our theoretical framework is general and can be used to study a wide variety of phenomena, such as spin transport and exciton transport.

  14. Using community-level metrics to monitor the effects of marine protected areas on biodiversity.

    PubMed

    Soykan, Candan U; Lewison, Rebecca L

    2015-06-01

    Marine protected areas (MPAs) are used to protect species, communities, and their associated habitats, among other goals. Measuring MPA efficacy can be challenging, however, particularly when considering responses at the community level. We gathered 36 abundance and 14 biomass data sets on fish assemblages and used meta-analysis to evaluate the ability of 22 distinct community diversity metrics to detect differences in community structure between MPAs and nearby control sites. We also considered the effects of 6 covariates-MPA size and age, MPA size and age interaction, latitude, total species richness, and level of protection-on each metric. Some common metrics, such as species richness and Shannon diversity, did not differ consistently between MPA and control sites, whereas other metrics, such as total abundance and biomass, were consistently different across studies. Metric responses derived from the biomass data sets were more consistent than those based on the abundance data sets, suggesting that community-level biomass differs more predictably than abundance between MPA and control sites. Covariate analyses indicated that level of protection, latitude, MPA size, and the interaction between MPA size and age affect metric performance. These results highlight a handful of metrics, several of which are little known, that could be used to meet the increasing demand for community-level indicators of MPA effectiveness.

  15. [Applicability of traditional landscape metrics in evaluating urban heat island effect].

    PubMed

    Chen, Ai-Lian; Sun, Ran-Hao; Chen, Li-Ding

    2012-08-01

    By using 24 landscape metrics, this paper evaluated the urban heat island effect in parts of Beijing downtown area. QuickBird (QB) images were used to extract the landscape type information, and the thermal bands from Landsat Enhanced Thematic Mapper Plus (ETM+) images were used to extract the land surface temperature (LST) in four seasons of the same year. The 24 landscape pattern metrics were calculated at landscape and class levels in a fixed window with 120 mx 120 m in size, with the applicability of these traditional landscape metrics in evaluating the urban heat island effect examined. Among the 24 landscape metrics, only the percentage composition of landscape (PLAND), patch density (PD), largest patch index (LPI), coefficient of Euclidean nearest-neighbor distance variance (ENN_CV), and landscape division index (DIVISION) at landscape level were significantly correlated with the LST in March, May, and November, and the PLAND, LPI, DIVISION, percentage of like adjacencies, and interspersion and juxtaposition index at class level showed significant correlations with the LST in March, May, July, and December, especially in July. Some metrics such as PD, edge density, clumpiness index, patch cohesion index, effective mesh size, splitting index, aggregation index, and normalized landscape shape index showed varying correlations with the LST at different class levels. The traditional landscape metrics could not be appropriate in evaluating the effects of river on LST, while some of the metrics could be useful in characterizing urban LST and analyzing the urban heat island effect, but screening and examining should be made on the metrics.

  16. Effect of quality metric monitoring and colonoscopy performance.

    PubMed

    Razzak, Anthony; Smith, Dineen; Zahid, Maliha; Papachristou, Georgios; Khalid, Asif

    2016-10-01

    Background and aims: Adenoma detection rate (ADR) and cecal withdrawal time (CWT) have been identified as measures of colonoscopy quality. This study evaluates the impact of monitoring these measures on provider performance. Methods: Six blinded gastroenterologists practicing at a Veterans Affairs Medical Center were prospectively monitored over 9 months. Data for screening, adenoma surveillance, and fecal occult blood test positive (FOBT +) indicated colonoscopies were obtained, including exam preparation quality, cecal intubation rate, CWT, ADR, adenomas per colonoscopy (APC), and adverse events. Metrics were continuously monitored after a period of informed CWT monitoring and informed CWT + ADR monitoring. The primary outcome was impact on ADR and APC. Results: A total of 1671 colonoscopies were performed during the study period with 540 before informed monitoring, 528 during informed CWT monitoring, and 603 during informed CWT + ADR monitoring. No statistically significant impact on ADR was noted across each study phase. Multivariate regression revealed a trend towards fewer adenomas removed during the CWT monitoring phase (OR = 0.79; 95 %CI 0.62 - 1.02, P = 0.065) and a trend towards more adenomas removed during the CWT + ADR monitoring phase when compared to baseline (OR = 1.26; 95 %CI 0.99 - 1.61, P = 0.062). Indication for examination and provider were significant predictors for higher APC. Provider-specific data demonstrated a direct relationship between high ADR performers and increased CWT. Conclusions: Monitoring quality metrics did not significantly alter colonoscopy performance across a small heterogeneous group of providers. Non-significant trends towards higher APC were noted with CWT + ADR monitoring. Providers with a longer CWT had a higher ADR. Further studies are needed to determine the impact of monitoring on colonoscopy performance.

  17. Effect of quality metric monitoring and colonoscopy performance

    PubMed Central

    Razzak, Anthony; Smith, Dineen; Zahid, Maliha; Papachristou, Georgios; Khalid, Asif

    2016-01-01

    Background and aims: Adenoma detection rate (ADR) and cecal withdrawal time (CWT) have been identified as measures of colonoscopy quality. This study evaluates the impact of monitoring these measures on provider performance. Methods: Six blinded gastroenterologists practicing at a Veterans Affairs Medical Center were prospectively monitored over 9 months. Data for screening, adenoma surveillance, and fecal occult blood test positive (FOBT +) indicated colonoscopies were obtained, including exam preparation quality, cecal intubation rate, CWT, ADR, adenomas per colonoscopy (APC), and adverse events. Metrics were continuously monitored after a period of informed CWT monitoring and informed CWT + ADR monitoring. The primary outcome was impact on ADR and APC. Results: A total of 1671 colonoscopies were performed during the study period with 540 before informed monitoring, 528 during informed CWT monitoring, and 603 during informed CWT + ADR monitoring. No statistically significant impact on ADR was noted across each study phase. Multivariate regression revealed a trend towards fewer adenomas removed during the CWT monitoring phase (OR = 0.79; 95 %CI 0.62 – 1.02, P = 0.065) and a trend towards more adenomas removed during the CWT + ADR monitoring phase when compared to baseline (OR = 1.26; 95 %CI 0.99 – 1.61, P = 0.062). Indication for examination and provider were significant predictors for higher APC. Provider-specific data demonstrated a direct relationship between high ADR performers and increased CWT. Conclusions: Monitoring quality metrics did not significantly alter colonoscopy performance across a small heterogeneous group of providers. Non-significant trends towards higher APC were noted with CWT + ADR monitoring. Providers with a longer CWT had a higher ADR. Further studies are needed to determine the impact of monitoring on colonoscopy performance. PMID:27747273

  18. Effect of thematic map misclassification on landscape multi-metric assessment.

    PubMed

    Kleindl, William J; Powell, Scott L; Hauer, F Richard

    2015-06-01

    Advancements in remote sensing and computational tools have increased our awareness of large-scale environmental problems, thereby creating a need for monitoring, assessment, and management at these scales. Over the last decade, several watershed and regional multi-metric indices have been developed to assist decision-makers with planning actions of these scales. However, these tools use remote-sensing products that are subject to land-cover misclassification, and these errors are rarely incorporated in the assessment results. Here, we examined the sensitivity of a landscape-scale multi-metric index (MMI) to error from thematic land-cover misclassification and the implications of this uncertainty for resource management decisions. Through a case study, we used a simplified floodplain MMI assessment tool, whose metrics were derived from Landsat thematic maps, to initially provide results that were naive to thematic misclassification error. Using a Monte Carlo simulation model, we then incorporated map misclassification error into our MMI, resulting in four important conclusions: (1) each metric had a different sensitivity to error; (2) within each metric, the bias between the error-naive metric scores and simulated scores that incorporate potential error varied in magnitude and direction depending on the underlying land cover at each assessment site; (3) collectively, when the metrics were combined into a multi-metric index, the effects were attenuated; and (4) the index bias indicated that our naive assessment model may overestimate floodplain condition of sites with limited human impacts and, to a lesser extent, either over- or underestimated floodplain condition of sites with mixed land use.

  19. Metric Madness

    ERIC Educational Resources Information Center

    Kroon, Cindy D.

    2007-01-01

    Created for a Metric Day activity, Metric Madness is a board game for two to four players. Students review and practice metric vocabulary, measurement, and calculations by playing the game. Playing time is approximately twenty to thirty minutes.

  20. Developing Metrics for Effective Teaching in Agricultural Education

    ERIC Educational Resources Information Center

    Lawver, Rebecca G.; McKim, Billy R.; Smith, Amy R.; Aschenbrener, Mollie S.; Enns, Kellie

    2016-01-01

    Research on effective teaching has been conducted in a variety of settings for more than 40 years. This study offers direction for future effective teaching research in secondary agricultural education and has implications for career and technical education. Specifically, 142 items consisting of characteristics, behaviors, and/or techniques…

  1. On the Doppler effect for light from orbiting sources in Kerr-type metrics

    NASA Astrophysics Data System (ADS)

    Cisneros, S.; Goedecke, G.; Beetle, C.; Engelhardt, M.

    2015-04-01

    A formula is derived for the combined motional and gravitational Doppler effect in general stationary axisymmetric metrics for a photon emitted parallel or antiparallel to the assumed circular orbital motion of its source. The same formula is derived by both the eikonal approximation and Killing vector approaches to elucidate connections between observational astronomy and modern relativity. The formula yields expected results in the limits of a moving or stationary source in the exterior Kerr and Schwarzschild metrics and is useful for broad range astrophysical analyses.

  2. THE EFFECT OF VARYING ELECTROFISHING DESIGNS AND DISTANCES ON METRIC SCORES IN LARGE RIVERS

    EPA Science Inventory

    To study the effects of electrofishing design and distance on metric scores, we electrofished almost 180 km across four rivers of the Ohio River basin and collected data on more than 28,000 fish. We compared three electrofishing designs using four fish assemblage composition met...

  3. THE EFFECT OF VARYING ELECTROFISHING DESIGNS AND DISTANCES ON METRIC SCORES IN LARGE RIVERS

    EPA Science Inventory

    To study the effects of electrofishing design and distance on metric scores, we electrofished almost 180 km across four rivers of the Ohio River basin and collected data on more than 28,000 fish. We compared three electrofishing designs using four fish assemblage composition met...

  4. Development of Performance and Effectiveness Metrics For Mechanical Diagnostic Technologies

    DTIC Science & Technology

    2001-04-05

    this need , a virtual test bench is under development by the Navy for assessing the performance and effectiveness of machinery diagnostic systems. The...benefits of mechanical machinery diagnostic technologies does not currently exist. In response to this need , a virtual test bench is 375 under...thermocouples, acoustic emission sensors, and oil debris sensors. Tests are run at various load and speed profiles while 381 logging measurement signals for

  5. Metrics to describe the effects of landscape pattern on hydrology in a lotic peatland

    NASA Astrophysics Data System (ADS)

    Yuan, J.; Cohen, M. J.; Kaplan, D. A.; Acharya, S.; Larsen, L.; Nungesser, M.

    2013-12-01

    Strong reciprocal interactions exist between landscape patterns and ecological processes. Hydrology is the dominant abiotic driver of ecological processes in wetlands, particularly flowing wetlands, but is both the control on and controlled by the geometry of vegetation patterning. Landscape metrics are widely used to quantitatively link pattern and process. Our goal here was to use several candidate spatial pattern metrics to predict the effects of wetland vegetation pattern on hydrologic regime, specifically hydroperiod, in the ridge-slough patterned landscape of the Everglades. The metrics focus on the capacity for longitudinally connected flow, and thus the ability of this low-gradient patterned landscape to route water from upstream. We first explored flow friction cost (FFC), a weighted spatial distance procedure wherein ridges have a high flow cost than sloughs by virtue of their elevation and vegetation structure, to evaluate water movement through different landscape configurations. We also investigated existing published flow metrics, specifically the Directional Connectivity Index (DCI) and Landscape Discharge Competence (LDC), that seek to quantify connectivity, one of the sentinel targets of ecological restoration. Hydroperiod was estimated using a numerical hydrologic model (SWIFT 2D) in real and synthetic landscapes with varying vegetation properties ( patch anisotropy, ridge density). Synthetic landscapes were constrained by the geostatistical properties of the best conserved patterned, and contained five anisotropy levels and seven ridge density levels. These were used to construct the relationship between landscape metrics and hydroperiod. Then, using historical images from 1940 to 2004, we applied the metrics toback-cast hydroperiod. Current vegetation maps were used to test scale dependency for each metric. Our results suggest that both FFC and DCI are good predictors of hydroperiod under free flowing conditions, and that they can be used

  6. Effectively identifying user profiles in network and host metrics

    NASA Astrophysics Data System (ADS)

    Murphy, John P.; Berk, Vincent H.; Gregorio-de Souza, Ian

    2010-04-01

    This work presents a collection of methods that is used to effectively identify users of computers systems based on their particular usage of the software and the network. Not only are we able to identify individual computer users by their behavioral patterns, we are also able to detect significant deviations in their typical computer usage over time, or compared to a group of their peers. For instance, most people have a small, and relatively unique selection of regularly visited websites, certain email services, daily work hours, and typical preferred applications for mandated tasks. We argue that these habitual patterns are sufficiently specific to identify fully anonymized network users. We demonstrate that with only a modest data collection capability, profiles of individual computer users can be constructed so as to uniquely identify a profiled user from among their peers. As time progresses and habits or circumstances change, the methods presented update each profile so that changes in user behavior can be reliably detected over both abrupt and gradual time frames, without losing the ability to identify the profiled user. The primary benefit of our methodology allows one to efficiently detect deviant behaviors, such as subverted user accounts, or organizational policy violations. Thanks to the relative robustness, these techniques can be used in scenarios with very diverse data collection capabilities, and data privacy requirements. In addition to behavioral change detection, the generated profiles can also be compared against pre-defined examples of known adversarial patterns.

  7. Effect of respiratory and cardiac gating on the major diffusion-imaging metrics.

    PubMed

    Hamaguchi, Hiroyuki; Tha, Khin Khin; Sugimori, Hiroyuki; Nakanishi, Mitsuhiro; Nakagawa, Shin; Fujiwara, Taro; Yoshida, Hirokazu; Takamori, Sayaka; Shirato, Hiroki

    2016-08-01

    The effect of respiratory gating on the major diffusion-imaging metrics and that of cardiac gating on mean kurtosis (MK) are not known. For evaluation of whether the major diffusion-imaging metrics-MK, fractional anisotropy (FA), and mean diffusivity (MD) of the brain-varied between gated and non-gated acquisitions, respiratory-gated, cardiac-gated, and non-gated diffusion-imaging of the brain were performed in 10 healthy volunteers. MK, FA, and MD maps were constructed for all acquisitions, and the histograms were constructed. The normalized peak height and location of the histograms were compared among the acquisitions by use of Friedman and post hoc Wilcoxon tests. The effect of the repetition time (TR) on the diffusion-imaging metrics was also tested, and we corrected for its variation among acquisitions, if necessary. The results showed a shift in the peak location of the MK and MD histograms to the right with an increase in TR (p ≤ 0.01). The corrected peak location of the MK histograms, the normalized peak height of the FA histograms, the normalized peak height and the corrected peak location of the MD histograms varied significantly between the gated and non-gated acquisitions (p < 0.05). These results imply an influence of respiration and cardiac pulsation on the major diffusion-imaging metrics. The gating conditions must be kept identical if reproducible results are to be achieved.

  8. The Use of Performance Metrics for the Assessment of Safeguards Effectiveness at the State Level

    SciTech Connect

    Bachner K. M.; George Anzelon, Lawrence Livermore National Laboratory, Livermore, CA Yana Feldman, Lawrence Livermore National Laboratory, Livermore, CA Mark Goodman,Department of State, Washington, DC Dunbar Lockwood, National Nuclear Security Administration, Washington, DC Jonathan B. Sanborn, JBS Consulting, LLC, Arlington, VA.

    2016-07-24

    In the ongoing evolution of International Atomic Energy Agency (IAEA) safeguards at the state level, many safeguards implementation principles have been emphasized: effectiveness, efficiency, non-discrimination, transparency, focus on sensitive materials, centrality of material accountancy for detecting diversion, independence, objectivity, and grounding in technical considerations, among others. These principles are subject to differing interpretations and prioritizations and sometimes conflict. This paper is an attempt to develop metrics and address some of the potential tradeoffs inherent in choices about how various safeguards policy principles are implemented. The paper carefully defines effective safeguards, including in the context of safeguards approaches that take account of the range of state-specific factors described by the IAEA Secretariat and taken note of by the Board in September 2014, and (2) makes use of performance metrics to help document, and to make transparent, how safeguards implementation would meet such effectiveness requirements.

  9. Mediterranean dryland Mosaic: The effect of scale on core area metrics

    NASA Astrophysics Data System (ADS)

    Alhamad, Mohammad Noor; Alrababah, Mohammad

    2014-05-01

    Quantifying landscape spatial pattern is essential to understanding the relationship between landscape structure and ecological functions and process. Many landscape metrics have been developed to quantify spatial heterogeneity. Landscape metrics have been employed to measure the impact of humans on landscapes. We examined the response of four core areas metrics to a large range of grain sizes in Mediterranean dryland landscapes. The investigated metrics were (1) mean core area (CORE-MN), (2) area weighted mean core area (CORE-AM) , (3) total core area (TCA) and (4) core area percentage of landscape (CPLAND) within six land use types (urban, agriculture, olive orchids, forestry, shrubland and rangeland). Agriculture areas showed the highest value for minimum TCA (2779.4 ha) within the tested grain sizes, followed by rangeland (1778.3 ha) and Forest (1488.5 ha). On the other hand, shrubland showed the lowest TCA (8.0 ha). The minimum CPLAND values were ranged from 0.002 for shrubland to 0.682 for agriculture land use. The maximum CORE-MN among the tested land use type at all levels of grain sizes was exhibited by agriculture land use type (519.759 ha). The core area metrics showed three types of behavior in response to changing grain size in all landuse types. CORE-MN showed predictable relationship, best explained by non-linear responses to changing grain size (R2=0.99). Both TCA and CPLAND exhibited domain of scale effect in response to changing grain size. The threshold behavior for TCA and CPLAND was at the 4 x 4 grain size (about 1.3 ha). However, CORE-AM exhibited erratic behavior. The unique domain of scale-like behavior may be attributed to the unique characteristics of dryland Mediterranean landscapes; where both natural processes and ancient human activities play a great role in shaping the apparent pattern of the landscape

  10. Effective resist profile control

    NASA Astrophysics Data System (ADS)

    Liu, Chen-Yu; Wang, Chien-Wei; Huang, Chun-Ching; Chang, Ching-Yu; Ku, Yao-Ching

    2014-03-01

    To meet Moore's law, resist resolution improvement has become more and more important. However, it is difficult to improve resist resolution and keep vertical sidewall profile. For example, a high contrast hole resist may cause trench scum, due to very T-top profile. This paper reports several concepts for resist profile tuning without losing performance for lithographic factor , including mask error enhancement factor (MEEF), depth of focus (DOF), and critical dimension uniformity (CDU). To quantitative analysis the resist profile improvement, we define a new factor, Scum fail ratio (F/R%) for new techniques evaluation. The new techniques, including floatable additive, floatable PAG, and new monomer, are discussed. From X-SEM and CD-SEM data, former three concepts could improve resist sidewall profile quantitatively evaluated by Scum fail F/R% and keep lithographic factors. In addition, another key factor, resist residue defect, is also discussed. The high contrast resist with higher receding contact angle (RCA) easily generates more residue defect after development. With the new monomer composition, RCA of Resist E is decreased from 54 to 48 degree after development. Therefore, the residue defect is improved one order.

  11. Effects of certain key metrics of hydroentanglement system on properties of nonwoven fabrics made with commercially cleaned greige cotton

    USDA-ARS?s Scientific Manuscript database

    Research was conducted to determine the effects of certain key process metrics of a commercial-grade hydroentanglement system on properties of the nonwoven fabrics made with cleaned Upland greige cotton lint. The metrics studied, among others, were the hydroentangling water pressure, the strip orif...

  12. MDA Establishes Effective Metrics for Energy Reduction and Other Environmental Performance Improvements

    DTIC Science & Technology

    2009-05-06

    1 MISSILE DEFENSE AGENCY May 6, 2009 MDA Establishes Effective Metrics for Energy Reduction and Other Environmental Performance Improvements Dr...Reduction and Other Environmental Performance Improvements 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) 5d. PROJECT NUMBER...Standard Form 298 (Rev. 8-98) Prescribed by ANSI Std Z39-18 2 Purpose of the Presentation  Highlight elements of MDA Environmental Sustainability

  13. Color Metric.

    ERIC Educational Resources Information Center

    Illinois State Office of Education, Springfield.

    This booklet was designed to convey metric information in pictoral form. The use of pictures in the coloring book enables the more mature person to grasp the metric message instantly, whereas the younger person, while coloring the picture, will be exposed to the metric information long enough to make the proper associations. Sheets of the booklet…

  14. Color Metric.

    ERIC Educational Resources Information Center

    Illinois State Office of Education, Springfield.

    This booklet was designed to convey metric information in pictoral form. The use of pictures in the coloring book enables the more mature person to grasp the metric message instantly, whereas the younger person, while coloring the picture, will be exposed to the metric information long enough to make the proper associations. Sheets of the booklet…

  15. Comparing exposure metrics for the effects of fine particulate matter on emergency hospital admissions.

    PubMed

    Mannshardt, Elizabeth; Sucic, Katarina; Jiao, Wan; Dominici, Francesca; Frey, H Christopher; Reich, Brian; Fuentes, Montserrat

    2013-01-01

    A crucial step in an epidemiological study of the effects of air pollution is to accurately quantify exposure of the population. In this paper, we investigate the sensitivity of the health effects estimates associated with short-term exposure to fine particulate matter with respect to three potential metrics for daily exposure: ambient monitor data, estimated values from a deterministic atmospheric chemistry model, and stochastic daily average human exposure simulation output. Each of these metrics has strengths and weaknesses when estimating the association between daily changes in ambient exposure to fine particulate matter and daily emergency hospital admissions. Monitor data is readily available, but is incomplete over space and time. The atmospheric chemistry model output is spatially and temporally complete but may be less accurate than monitor data. The stochastic human exposure estimates account for human activity patterns and variability in pollutant concentration across microenvironments, but requires extensive input information and computation time. To compare these metrics, we consider a case study of the association between fine particulate matter and emergency hospital admissions for respiratory cases for the Medicare population across three counties in New York. Of particular interest is to quantify the impact and/or benefit to using the stochastic human exposure output to measure ambient exposure to fine particulate matter. Results indicate that the stochastic human exposure simulation output indicates approximately the same increase in the relative risk associated with emergency admissions as using a chemistry model or monitoring data as exposure metrics. However, the stochastic human exposure simulation output and the atmospheric chemistry model both bring additional information, which helps to reduce the uncertainly in our estimated risk.

  16. Effective dose efficiency: an application-specific metric of quality and dose for digital radiography.

    PubMed

    Samei, Ehsan; Ranger, Nicole T; Dobbins, James T; Ravin, Carl E

    2011-08-21

    The detective quantum efficiency (DQE) and the effective DQE (eDQE) are relevant metrics of image quality for digital radiography detectors and systems, respectively. The current study further extends the eDQE methodology to technique optimization using a new metric of the effective dose efficiency (eDE), reflecting both the image quality as well as the effective dose (ED) attributes of the imaging system. Using phantoms representing pediatric, adult and large adult body habitus, image quality measurements were made at 80, 100, 120 and 140 kVp using the standard eDQE protocol and exposures. ED was computed using Monte Carlo methods. The eDE was then computed as a ratio of image quality to ED for each of the phantom/spectral conditions. The eDQE and eDE results showed the same trends across tube potential with 80 kVp yielding the highest values and 120 kVp yielding the lowest. The eDE results for the pediatric phantom were markedly lower than the results for the adult phantom at spatial frequencies lower than 1.2-1.7 mm(-1), primarily due to a correspondingly higher value of ED per entrance exposure. The relative performance for the adult and large adult phantoms was generally comparable but affected by kVps. The eDE results for the large adult configuration were lower than the eDE results for the adult phantom, across all spatial frequencies (120 and 140 kVp) and at spatial frequencies greater than 1.0 mm(-1) (80 and 100 kVp). Demonstrated for chest radiography, the eDE shows promise as an application-specific metric of imaging performance, reflective of body habitus and radiographic technique, with utility for radiography protocol assessment and optimization.

  17. Effects of metric change on safety in the workplace for selected occupations

    NASA Astrophysics Data System (ADS)

    Lefande, J. M.; Pokorney, J. L.

    1982-04-01

    The study assesses the potential safety issues of metric conversion in the workplace. A purposive sample of 35 occupations based on injury and illnesses indexes were assessed. After an analysis of workforce population, hazard analysis and measurement sensitivity of the occupations, jobs were analyzed to identify potential safety hazards by industrial hygienists, safety engineers and academia. The study's major findings were as follows: No metric hazard experience was identified. An increased exposure might occur when particular jobs and their job tasks are going the transition from customary measurement to metric measurement. Well planned metric change programs reduce hazard potential. Metric safety issues are unresolved in the aviation industry.

  18. Effective Saturation: a More Informative Metric for Comparing Peak Separation in One- and Two-Dimensional Separations

    PubMed Central

    Carr, Peter W.

    2011-01-01

    A theoretical comparison is made of the numbers of observed peaks in one-dimensional (1D) and two-dimensional (2D) separations having the same peak capacity, as calculated from the traditional metric of resolution. The shortcoming of the average minimum resolution of statistical overlap theory (SOT) for this comparison is described. A new metric called the “effective saturation” is introduced to ameliorate the shortcoming. Unlike the “saturation”, which is the usual metric of peak crowding in SOT, the effective saturation is independent of the average minimum resolution and can be determined using traditional values of resolution and peak capacity. Our most important finding is that under a wide range of practical conditions, 1D and 2D separations of the same mixture produce almost equal numbers of observed peaks when the traditional peak capacities of the separations are the same, provided that the effective saturation and not the usual saturation is used as the measure of crowding. This is the case when peak distributions are random and when edge effects are minor. The numerical results supporting this finding can be described by empirical functions of the effective saturation, including one for the traditional peak capacity needed to separate a given fraction of mixture constituents as observed peaks. The near equality of the number of observed peaks in 1D and 2D separations based on the effective saturation is confirmed by simulations. However, this equality is compromised in 2D separations when edge effects are large. The new finding does not contradict previous predictions by SOT of differences between 1D and 2D separations at equal saturation. Indeed, the simulations reaffirm their validity. Rather, the usual metric, i.e., the saturation, is just not as simple a metric for comparing 1D and 2D separations as is the new metric, i.e., the effective saturation. We strongly recommend use of the new metric for its great simplifying effect. PMID:19178343

  19. Assessing the Effects of Data Compression in Simulations Using Physically Motivated Metrics

    DOE PAGES

    Laney, Daniel; Langer, Steven; Weber, Christopher; ...

    2014-01-01

    This paper examines whether lossy compression can be used effectively in physics simulations as a possible strategy to combat the expected data-movement bottleneck in future high performance computing architectures. We show that, for the codes and simulations we tested, compression levels of 3–5X can be applied without causing significant changes to important physical quantities. Rather than applying signal processing error metrics, we utilize physics-based metrics appropriate for each code to assess the impact of compression. We evaluate three different simulation codes: a Lagrangian shock-hydrodynamics code, an Eulerian higher-order hydrodynamics turbulence modeling code, and an Eulerian coupled laser-plasma interaction code. Wemore » compress relevant quantities after each time-step to approximate the effects of tightly coupled compression and study the compression rates to estimate memory and disk-bandwidth reduction. We find that the error characteristics of compression algorithms must be carefully considered in the context of the underlying physics being modeled.« less

  20. Forensic Metrics

    ERIC Educational Resources Information Center

    Bort, Nancy

    2005-01-01

    One of the most important review topics the author teaches in middle school is the use of metric measurement for problem solving and inquiry. For many years, she had students measuring various objects around the room using the tools of metric measurement. She dutifully taught hypothesizing, data collecting, and drawing conclusions. It was…

  1. Primary Metrics.

    ERIC Educational Resources Information Center

    Otto, Karen; And Others

    These 55 activity cards were created to help teachers implement a unit on metric measurement. They were designed for students aged 5 to 10, but could be used with older students. Cards are color-coded in terms of activities on basic metric terms, prefixes, length, and other measures. Both individual and small-group games and ideas are included.…

  2. Mastering Metrics

    ERIC Educational Resources Information Center

    Parrot, Annette M.

    2005-01-01

    By the time students reach a middle school science course, they are expected to make measurements using the metric system. However, most are not practiced in its use, as their experience in metrics is often limited to one unit they were taught in elementary school. This lack of knowledge is not wholly the fault of formal education. Although the…

  3. Mastering Metrics

    ERIC Educational Resources Information Center

    Parrot, Annette M.

    2005-01-01

    By the time students reach a middle school science course, they are expected to make measurements using the metric system. However, most are not practiced in its use, as their experience in metrics is often limited to one unit they were taught in elementary school. This lack of knowledge is not wholly the fault of formal education. Although the…

  4. Forensic Metrics

    ERIC Educational Resources Information Center

    Bort, Nancy

    2005-01-01

    One of the most important review topics the author teaches in middle school is the use of metric measurement for problem solving and inquiry. For many years, she had students measuring various objects around the room using the tools of metric measurement. She dutifully taught hypothesizing, data collecting, and drawing conclusions. It was…

  5. Comparing Single Case Design Overlap-Based Effect Size Metrics From Studies Examining Speech Generating Device Interventions

    PubMed Central

    Chen, Mo; Hyppa-Martin, Jolene K.; Reichle, Joe E.; Symons, Frank J.

    2017-01-01

    Meaningfully synthesizing single case experimental data from intervention studies comprised of individuals with low incidence conditions and generating effect size estimates remains challenging. Seven effect size metrics were compared for single case design (SCD) data focused on teaching speech generating device use to individuals with intellectual and developmental disabilities (IDD) with moderate to profound levels of impairment. The effect size metrics included percent of data points exceeding the median (PEM), percent of nonoverlapping data (PND), improvement rate difference (IRD), percent of all nonoverlapping data (PAND), Phi, nonoverlap of all pairs (NAP), and Taunovlap. Results showed that among the seven effect size metrics, PAND, Phi, IRD, and PND were more effective in quantifying intervention effects for the data sample (N = 285 phase or condition contrasts). Results are discussed with respect to issues concerning extracting and calculating effect sizes, visual analysis, and SCD intervention research in IDD. PMID:27119210

  6. Topics in Metric Approximation

    NASA Astrophysics Data System (ADS)

    Leeb, William Edward

    This thesis develops effective approximations of certain metrics that occur frequently in pure and applied mathematics. We show that distances that often arise in applications, such as the Earth Mover's Distance between two probability measures, can be approximated by easily computed formulas for a wide variety of ground distances. We develop simple and easily computed characterizations both of norms measuring a function's regularity -- such as the Lipschitz norm -- and of their duals. We are particularly concerned with the tensor product of metric spaces, where the natural notion of regularity is not the Lipschitz condition but the mixed Lipschitz condition. A theme that runs throughout this thesis is that snowflake metrics (metrics raised to a power less than 1) are often better-behaved than ordinary metrics. For example, we show that snowflake metrics on finite spaces can be approximated by the average of tree metrics with a distortion bounded by intrinsic geometric characteristics of the space and not the number of points. Many of the metrics for which we characterize the Lipschitz space and its dual are snowflake metrics. We also present applications of the characterization of certain regularity norms to the problem of recovering a matrix that has been corrupted by noise. We are able to achieve an optimal rate of recovery for certain families of matrices by exploiting the relationship between mixed-variable regularity conditions and the decay of a function's coefficients in a certain orthonormal basis.

  7. Effect of NOAA satellite orbital drift on AVHRR-derived phenological metrics

    USGS Publications Warehouse

    Ji, Lei; Brown, Jesslyn

    2017-01-01

    The U.S. Geological Survey (USGS) Earth Resources Observation and Science (EROS) Center routinely produces and distributes a remote sensing phenology (RSP) dataset derived from the Advanced Very High Resolution Radiometer (AVHRR) 1-km data compiled from a series of National Oceanic and Atmospheric Administration (NOAA) satellites (NOAA-11, −14, −16, −17, −18, and −19). Each NOAA satellite experienced orbital drift during its duty period, which influenced the AVHRR reflectance measurements. To understand the effect of the orbital drift on the AVHRR-derived RSP dataset, we analyzed the impact of solar zenith angle (SZA) on the RSP metrics in the conterminous United States (CONUS). The AVHRR weekly composites were used to calculate the growing-season median SZA at the pixel level for each year from 1989 to 2014. The results showed that the SZA increased towards the end of each NOAA satellite mission with the highest increasing rate occurring during NOAA-11 (1989–1994) and NOAA-14 (1995–2000) missions. The growing-season median SZA values (44°–60°) in 1992, 1993, 1994, 1999, and 2000 were substantially higher than those in other years (28°–40°). The high SZA in those years caused negative trends in the SZA time series, that were statistically significant (at α = 0.05 level) in 76.9% of the CONUS area. A pixel-based temporal correlation analysis showed that the phenological metrics and SZA were significantly correlated (at α = 0.05 level) in 4.1–20.4% of the CONUS area. After excluding the 5 years with high SZA (>40°) from the analysis, the temporal SZA trend was largely reduced, significantly affecting less than 2% of the study area. Additionally, significant correlation between the phenological metrics and SZA was observed in less than 7% of the study area. Our study concluded that the NOAA satellite orbital drift increased SZA, and in turn, influenced the phenological metrics. Elimination of the years with high median SZA reduced the

  8. Effect of NOAA satellite orbital drift on AVHRR-derived phenological metrics

    NASA Astrophysics Data System (ADS)

    Ji, Lei; Brown, Jesslyn F.

    2017-10-01

    The U.S. Geological Survey (USGS) Earth Resources Observation and Science (EROS) Center routinely produces and distributes a remote sensing phenology (RSP) dataset derived from the Advanced Very High Resolution Radiometer (AVHRR) 1-km data compiled from a series of National Oceanic and Atmospheric Administration (NOAA) satellites (NOAA-11, -14, -16, -17, -18, and -19). Each NOAA satellite experienced orbital drift during its duty period, which influenced the AVHRR reflectance measurements. To understand the effect of the orbital drift on the AVHRR-derived RSP dataset, we analyzed the impact of solar zenith angle (SZA) on the RSP metrics in the conterminous United States (CONUS). The AVHRR weekly composites were used to calculate the growing-season median SZA at the pixel level for each year from 1989 to 2014. The results showed that the SZA increased towards the end of each NOAA satellite mission with the highest increasing rate occurring during NOAA-11 (1989-1994) and NOAA-14 (1995-2000) missions. The growing-season median SZA values (44°-60°) in 1992, 1993, 1994, 1999, and 2000 were substantially higher than those in other years (28°-40°). The high SZA in those years caused negative trends in the SZA time series, that were statistically significant (at α = 0.05 level) in 76.9% of the CONUS area. A pixel-based temporal correlation analysis showed that the phenological metrics and SZA were significantly correlated (at α = 0.05 level) in 4.1-20.4% of the CONUS area. After excluding the 5 years with high SZA (>40°) from the analysis, the temporal SZA trend was largely reduced, significantly affecting less than 2% of the study area. Additionally, significant correlation between the phenological metrics and SZA was observed in less than 7% of the study area. Our study concluded that the NOAA satellite orbital drift increased SZA, and in turn, influenced the phenological metrics. Elimination of the years with high median SZA reduced the influence of orbital drift

  9. Spectrum splitting metrics and effect of filter characteristics on photovoltaic system performance.

    PubMed

    Russo, Juan M; Zhang, Deming; Gordon, Michael; Vorndran, Shelby; Wu, Yuechen; Kostuk, Raymond K

    2014-03-10

    During the past few years there has been a significant interest in spectrum splitting systems to increase the overall efficiency of photovoltaic solar energy systems. However, methods for comparing the performance of spectrum splitting systems and the effects of optical spectral filter design on system performance are not well developed. This paper addresses these two areas. The system conversion efficiency is examined in detail and the role of optical spectral filters with respect to the efficiency is developed. A new metric termed the Improvement over Best Bandgap is defined which expresses the efficiency gain of the spectrum splitting system with respect to a similar system that contains the highest constituent single bandgap photovoltaic cell. This parameter indicates the benefit of using the more complex spectrum splitting system with respect to a single bandgap photovoltaic system. Metrics are also provided to assess the performance of experimental spectral filters in different spectrum splitting configurations. The paper concludes by using the methodology to evaluate spectrum splitting systems with different filter configurations and indicates the overall efficiency improvement that is possible with ideal and experimental designs.

  10. Do-It-Yourself Metrics

    ERIC Educational Resources Information Center

    Klubeck, Martin; Langthorne, Michael; Padgett, Don

    2006-01-01

    Something new is on the horizon, and depending on one's role on campus, it might be storm clouds or a cleansing shower. Either way, no matter how hard one tries to avoid it, sooner rather than later he/she will have to deal with metrics. Metrics do not have to cause fear and resistance. Metrics can, and should, be a powerful tool for improvement.…

  11. But what do the numbers really tell us? Arbitrary metrics and effect size reporting in sport psychology research.

    PubMed

    Andersen, Mark B; McCullagh, Penny; Wilson, Gabriel J

    2007-10-01

    Many of the measurements used in sport psychology research are arbitrary metrics, and researchers often cannot make the jump from scores on paper-and-pencil tests to what those scores actually mean in terms of real-world behaviors. Effect sizes for behavioral data are often interpretable, but the meaning of a small, medium, or large effect for an arbitrary metric is elusive. We reviewed all the issues in the 2005 volumes of the Journal of Sport & Exercise Psychology, The Sport Psychologist, and the Journal of Applied Sport Psychology to determine whether the arbitrary metrics used in sport psychology research were interpreted, or calibrated, against real-world variables. Of the 54 studies that used quantitative methods, 25 reported only paper-and-pencil arbitrary metrics with no connections to behavior or other real-world variables. Also, 44 of the 54 studies reported effect sizes, but only 7 studies, using both arbitrary and behavioral metrics, had calculated effect indicators and interpreted them in terms of real-world meaning.

  12. Edible Metrics.

    ERIC Educational Resources Information Center

    Mecca, Christyna E.

    1998-01-01

    Presents an exercise that introduces students to scientific measurements using only metric units. At the conclusion of the exercise, students eat the experiment. Requires dried refried beans, crackers or chips, and dried instant powder for lemonade. (DDR)

  13. Detecting the effects of cascade hydropower reservoirs on eco-flow metrics

    NASA Astrophysics Data System (ADS)

    Zhao, T.; Zhao, J.

    2012-12-01

    Over evolutionary time, the natural hydrological events of floods and droughts have become an integral component of riverine ecosystems. However, human activities, particularly reservoir operations, can greatly alter the natural flow regime and pose great impacts on riverine ecosystems. This study analyses the effects of cascade hydropower reservoir operation on eco-flow metrics based on inflow and release data of reservoirs in southwest China, with a focus on the Xiaowan reservoir (upper reservoir with multi-annual storage capacity) and the Jinghong reservoir (lower reservoir with weekly storage capacity). For the upper Xiaowan Reservoir, the analysis results show that the eco-surplus and eco-deficit (Vogel, et al, 2007; Gao, et al., 2009 ) can capture its impacts of hydropower operation on eco-flow metrics very well. However, comparative analysis of the lower Jinghong reservoir based on daily and hourly data shows that eco-surplus and eco-deficit measured with flow duration curve of daily and hourly flow data are not sensitive indices, which is attributed to the small regulating capacity of the Jinghong reservoir. It is shown that the negative impacts of hydropower operation of the Jinghong reservoir can be characterized by the changing rate of flow. These results indicate that eco-surplus and eco-deficit are good representative indices for evaluating seasonal reservoir operation, but more attention should be paid to the changing rate of flow for short term hydropower reservoir operation. This study implies that coordination of cascade reservoirs can be an effective way to mitigate the negative impacts of hydropower operation on ecosystem.

  14. The effects of different shape-based metrics on the identification of military targets from 3D ladar data

    NASA Astrophysics Data System (ADS)

    Meyer, Gregory J.; Weber, James R.

    2006-02-01

    The choice of shape metrics is important to effectively identify three-dimensional targets. The performance (expressed as a probability of correct classification) of four metrics using point clouds of military targets rendered using Irma, a government tool that simulates the output of an active ladar system, is compared across multiple ranges, sampling densities, target types, and noise levels. After understanding the range of operating conditions a classifier would be expected to see in the field, a process for determining the upper-bound of a classifier and the significance of this result is assessed. Finally, the effect of sampling density and variance in the position estimates on classification performance is shown. Classification performance significantly decreases when sampling density exceeds 10 degrees and the voxelized histogram metric outperforms the other three metrics used in this paper because of its performance in high-noise environments. Most importantly, this paper highlights a step-by-step method to test and evaluate shape metrics using accurate target models.

  15. Comparing Single Case Design Overlap-Based Effect Size Metrics from Studies Examining Speech Generating Device Interventions

    ERIC Educational Resources Information Center

    Chen, Mo; Hyppa-Martin, Jolene K.; Reichle, Joe E.; Symons, Frank J.

    2016-01-01

    Meaningfully synthesizing single case experimental data from intervention studies comprised of individuals with low incidence conditions and generating effect size estimates remains challenging. Seven effect size metrics were compared for single case design (SCD) data focused on teaching speech generating device use to individuals with…

  16. Comparing Single Case Design Overlap-Based Effect Size Metrics from Studies Examining Speech Generating Device Interventions

    ERIC Educational Resources Information Center

    Chen, Mo; Hyppa-Martin, Jolene K.; Reichle, Joe E.; Symons, Frank J.

    2016-01-01

    Meaningfully synthesizing single case experimental data from intervention studies comprised of individuals with low incidence conditions and generating effect size estimates remains challenging. Seven effect size metrics were compared for single case design (SCD) data focused on teaching speech generating device use to individuals with…

  17. Measuring the effects of health information technology on quality of care: a novel set of proposed metrics for electronic quality reporting.

    PubMed

    Kern, Lisa M; Dhopeshwarkar, Rina; Barrón, Yolanda; Wilcox, Adam; Pincus, Harold; Kaushal, Rainu

    2009-07-01

    Electronic health records (EHRs), in combination with health information exchange, are being promoted in the United States as a strategy for improving quality of care. No single metric set exists for measuring the effectiveness of these interventions. A set of quality metrics was sought that could be retrieved electronically and would be sensitive to the changes in quality that EHRs with health information exchange may contribute to ambulatory care. A literature search identified quality metric sets for ambulatory care. Two rounds of quantitative rating of individual metrics were conducted. Metrics were developed de novo to capture additional expected effects of EHRs with health information exchange. A 36-member national expert panel validated the rating process and final metric set. Seventeen metric sets containing 1,064 individual metrics were identified; 510 metrics met inclusion criteria. Two rounds of rating narrowed these to 59 metrics and then to 18. The final 18 consisted of metrics for asthma, cardiovascular disease, congestive heart failure, diabetes, medication and allergy documentation, mental health, osteoporosis, and prevention. Fourteen metrics were developed de novo to address test ordering, medication management, referrals, follow-up after discharge, and revisits. The novel set of 32 metrics is proposed as suitable for electronic reporting to capture the potential quality effects of EHRs with health information exchange. This metric set may have broad utility as health information technology becomes increasingly common with funding from the federal stimulus package and other sources. This work may also stimulate discussion on improving how data are entered and extracted from clinically rich, electronic sources, with the goal of more accurately measuring and improving care.

  18. Evaluating Texture Compression Masking Effects Using Objective Image Quality Assessment Metrics.

    PubMed

    Griffin, Wesley; Olano, Marc

    2015-08-01

    Texture compression is widely used in real-time rendering to reduce storage and bandwidth requirements. Recent research in compression algorithms has explored both reduced fixed bit rate and variable bit rate algorithms. The results are evaluated at the individual texture level using mean square error, peak signal-to-noise ratio, or visual image inspection. We argue this is the wrong evaluation approach. Compression artifacts in individual textures are likely visually masked in final rendered images and this masking is not accounted for when evaluating individual textures. This masking comes from both geometric mapping of textures onto models and the effects of combining different textures on the same model such as diffuse, gloss, and bump maps. We evaluate final rendered images using rigorous perceptual error metrics. Our method samples the space of viewpoints in a scene, renders the scene from each viewpoint using variations of compressed textures, and then compares each to a ground truth using uncompressed textures from the same viewpoint. We show that masking has a significant effect on final rendered image quality, masking effects and perceptual sensitivity to masking varies by the type of texture, graphics hardware compression algorithms are too conservative, and reduced bit rates are possible while maintaining final rendered image quality.

  19. Cyber threat metrics.

    SciTech Connect

    Frye, Jason Neal; Veitch, Cynthia K.; Mateski, Mark Elliot; Michalski, John T.; Harris, James Mark; Trevino, Cassandra M.; Maruoka, Scott

    2012-03-01

    Threats are generally much easier to list than to describe, and much easier to describe than to measure. As a result, many organizations list threats. Fewer describe them in useful terms, and still fewer measure them in meaningful ways. This is particularly true in the dynamic and nebulous domain of cyber threats - a domain that tends to resist easy measurement and, in some cases, appears to defy any measurement. We believe the problem is tractable. In this report we describe threat metrics and models for characterizing threats consistently and unambiguously. The purpose of this report is to support the Operational Threat Assessment (OTA) phase of risk and vulnerability assessment. To this end, we focus on the task of characterizing cyber threats using consistent threat metrics and models. In particular, we address threat metrics and models for describing malicious cyber threats to US FCEB agencies and systems.

  20. What is "fallback"?: metrics needed to assess telemetry tag effects on anadromous fish behavior

    USGS Publications Warehouse

    Frank, Holly J.; Mather, Martha E.; Smith, Joseph M.; Muth, Robert M.; Finn, John T.; McCormick, Stephen D.

    2009-01-01

    Telemetry has allowed researchers to document the upstream migrations of anadromous fish in freshwater. In many anadromous alosine telemetry studies, researchers use downstream movements (“fallback”) as a behavioral field bioassay for adverse tag effects. However, these downstream movements have not been uniformly reported or interpreted. We quantified movement trajectories of radio-tagged anadromous alewives (Alosa pseudoharengus) in the Ipswich River, Massachusetts (USA) and tested blood chemistry of tagged and untagged fish held 24 h. A diverse repertoire of movements was observed, which could be quantified using (a) direction of initial movements, (b) timing, and (c) characteristics of bouts of coupled upstream and downstream movements (e.g., direction, distance, duration, and speed). Because downstream movements of individual fish were almost always made in combination with upstream movements, these should be examined together. Several of the movement patterns described here could fall under the traditional definition of “fallback” but were not necessarily aberrant. Because superficially similar movements could have quite different interpretations, post-tagging trajectories need more precise definitions. The set of metrics we propose here will help quantify tag effects in the field, and provide the basis for a conceptual framework that helps define the complicated behaviors seen in telemetry studies on alewives and other fish in the field.

  1. Brief educational interventions to improve performance on novel quality metrics in ambulatory settings in Kenya: A multi-site pre-post effectiveness trial.

    PubMed

    Korom, Robert Ryan; Onguka, Stephanie; Halestrap, Peter; McAlhaney, Maureen; Adam, Mary

    2017-01-01

    The quality of primary care delivered in resource-limited settings is low. While some progress has been made using educational interventions, it is not yet clear how to sustainably improve care for common acute illnesses in the outpatient setting. Management of urinary tract infection is particularly important in resource-limited settings, where it is commonly diagnosed and associated with high levels of antimicrobial resistance. We describe an educational programme targeting non-physician health care providers and its effects on various clinical quality metrics for urinary tract infection. We used a series of educational interventions including 1) formal introduction of a clinical practice guideline, 2) peer-to-peer chart review, and 3) peer-reviewed literature describing local antimicrobial resistance patterns. Interventions were conducted for clinical officers (N = 24) at two outpatient centers near Nairobi, Kenya over a one-year period. The medical records of 474 patients with urinary tract infections were scored on five clinical quality metrics, with the primary outcome being the proportion of cases in which the guideline-recommended antibiotic was prescribed. The results at baseline and following each intervention were compared using chi-squared tests and unpaired two-tailed T-tests for significance. Logistic regression analysis was used to assess for possible confounders. Clinician adherence to the guideline-recommended antibiotic improved significantly during the study period, from 19% at baseline to 68% following all interventions (Χ2 = 150.7, p < 0.001). The secondary outcome of composite quality score also improved significantly from an average of 2.16 to 3.00 on a five-point scale (t = 6.58, p < 0.001). Interventions had different effects at different clinical sites; the primary outcome of appropriate antibiotic prescription was met 83% of the time at Penda Health, and 50% of the time at AICKH, possibly reflecting differences in onboarding and

  2. Metric qualities of the cognitive behavioral assessment for outcome evaluation to estimate psychological treatment effects

    PubMed Central

    Bertolotti, Giorgio; Michielin, Paolo; Vidotto, Giulio; Sanavio, Ezio; Bottesi, Gioia; Bettinardi, Ornella; Zotti, Anna Maria

    2015-01-01

    Background Cognitive behavioral assessment for outcome evaluation was developed to evaluate psychological treatment interventions, especially for counseling and psychotherapy. It is made up of 80 items and five scales: anxiety, well-being, perception of positive change, depression, and psychological distress. The aim of the study was to present the metric qualities and to show validity and reliability of the five constructs of the questionnaire both in nonclinical and clinical subjects. Methods Four steps were completed to assess reliability and factor structure: criterion-related and concurrent validity, responsiveness, and convergent–divergent validity. A nonclinical group of 269 subjects was enrolled, as was a clinical group comprising 168 adults undergoing psychotherapy and psychological counseling provided by the Italian public health service. Results Cronbach’s alphas were between 0.80 and 0.91 for the clinical sample and between 0.74 and 0.91 in the nonclinical one. We observed an excellent structural validity for the five interrelated dimensions. The clinical group showed higher scores in the anxiety, depression, and psychological distress scales, as well as lower scores in well-being and perception of positive change scales than those observed in the nonclinical group. Responsiveness was large for the anxiety, well-being, and depression scales; the psychological distress and perception of positive change scales showed a moderate effect. Conclusion The questionnaire showed excellent psychometric properties, thus demonstrating that the questionnaire is a good evaluative instrument, with which to assess pre- and post-treatment outcomes. PMID:26442466

  3. Metric qualities of the cognitive behavioral assessment for outcome evaluation to estimate psychological treatment effects.

    PubMed

    Bertolotti, Giorgio; Michielin, Paolo; Vidotto, Giulio; Sanavio, Ezio; Bottesi, Gioia; Bettinardi, Ornella; Zotti, Anna Maria

    2015-01-01

    Cognitive behavioral assessment for outcome evaluation was developed to evaluate psychological treatment interventions, especially for counseling and psychotherapy. It is made up of 80 items and five scales: anxiety, well-being, perception of positive change, depression, and psychological distress. The aim of the study was to present the metric qualities and to show validity and reliability of the five constructs of the questionnaire both in nonclinical and clinical subjects. Four steps were completed to assess reliability and factor structure: criterion-related and concurrent validity, responsiveness, and convergent-divergent validity. A nonclinical group of 269 subjects was enrolled, as was a clinical group comprising 168 adults undergoing psychotherapy and psychological counseling provided by the Italian public health service. Cronbach's alphas were between 0.80 and 0.91 for the clinical sample and between 0.74 and 0.91 in the nonclinical one. We observed an excellent structural validity for the five interrelated dimensions. The clinical group showed higher scores in the anxiety, depression, and psychological distress scales, as well as lower scores in well-being and perception of positive change scales than those observed in the nonclinical group. Responsiveness was large for the anxiety, well-being, and depression scales; the psychological distress and perception of positive change scales showed a moderate effect. The questionnaire showed excellent psychometric properties, thus demonstrating that the questionnaire is a good evaluative instrument, with which to assess pre- and post-treatment outcomes.

  4. Effects of noise suppression on intelligibility. II: An attempt to validate physical metrics.

    PubMed

    Hilkhuysen, Gaston; Gaubitch, Nikolay; Brookes, Mike; Huckvale, Mark

    2014-01-01

    Using the data presented in the accompanying paper [Hilkhuysen et al., J. Acoust. Soc. Am. 131, 531-539 (2012)], the ability of six metrics to predict intelligibility of speech in noise before and after noise suppression was studied. The metrics considered were the Speech Intelligibility Index (SII), the fractional Articulation Index (fAI), the coherence intelligibility index based on the mid-levels in speech (CSIImid), an extension of the Normalized Coherence Metric (NCM+), a part of the speech-based envelope power model (pre-sEPSM), and the Short Term Objective Intelligibility measure (STOI). Three of the measures, SII, CSIImid, and NCM+, overpredicted intelligibility after noise reduction, whereas fAI underpredicted these intelligibilities. The pre-sEPSM metric worked well for speech in babble but failed with car noise. STOI gave the best predictions, but overall the size of intelligibility prediction errors were greater than the change in intelligibility caused by noise suppression. Suggestions for improvements of the metrics are discussed.

  5. Fault Management Metrics

    NASA Technical Reports Server (NTRS)

    Johnson, Stephen B.; Ghoshal, Sudipto; Haste, Deepak; Moore, Craig

    2017-01-01

    This paper describes the theory and considerations in the application of metrics to measure the effectiveness of fault management. Fault management refers here to the operational aspect of system health management, and as such is considered as a meta-control loop that operates to preserve or maximize the system's ability to achieve its goals in the face of current or prospective failure. As a suite of control loops, the metrics to estimate and measure the effectiveness of fault management are similar to those of classical control loops in being divided into two major classes: state estimation, and state control. State estimation metrics can be classified into lower-level subdivisions for detection coverage, detection effectiveness, fault isolation and fault identification (diagnostics), and failure prognosis. State control metrics can be classified into response determination effectiveness and response effectiveness. These metrics are applied to each and every fault management control loop in the system, for each failure to which they apply, and probabilistically summed to determine the effectiveness of these fault management control loops to preserve the relevant system goals that they are intended to protect.

  6. Effects of Common Data Errors in Electronic Health Records on Emergency Department Operational Performance Metrics: A Monte Carlo Simulation

    PubMed Central

    Ward, Michael J.; Self, Wesley H.; Froehle, Craig M.

    2015-01-01

    Objectives To estimate how data errors in electronic health records (EHR) can affect the accuracy of common emergency department (ED) operational performance metrics. Methods Using a 3-month, 7,348-visit dataset of electronic timestamps from a suburban academic ED as a baseline, Monte Carlo simulation was used to introduce four types of data errors (substitution, missing, random, and systematic bias) at three frequency levels (2%, 4%, and 7%). Three commonly used ED operational metrics (arrival to clinician evaluation, disposition decision to exit for admitted patients, and ED length of stay for admitted patients) were calculated and the proportion of ED visits that achieved each performance goal was determined. Results Even small data errors have measurable effects on a clinical organization's ability to accurately determine whether it is meeting its operational performance goals. Systematic substitution errors, increased frequency of errors, and the use of shorter-duration metrics resulted in a lower proportion of ED visits reported as meeting the associated performance objectives. However, the presence of other error types mitigated somewhat the effect of the systematic substitution error. Longer time-duration metrics were found to be less sensitive to data errors than shorter time-duration metrics. Conclusions Infrequent and small-magnitude data errors in EHR timestamps can compromise a clinical organization's ability to determine accurately if it is meeting performance goals. By understanding the types and frequencies of data errors in an organization's EHR, organizational leaders can use data-management best practices to better measure true performance and enhance operational decision-making. PMID:26291051

  7. Metrication study for large space telescope

    NASA Technical Reports Server (NTRS)

    Creswick, F. A.; Weller, A. E.

    1973-01-01

    Various approaches which could be taken in developing a metric-system design for the Large Space Telescope, considering potential penalties on development cost and time, commonality with other satellite programs, and contribution to national goals for conversion to the metric system of units were investigated. Information on the problems, potential approaches, and impacts of metrication was collected from published reports on previous aerospace-industry metrication-impact studies and through numerous telephone interviews. The recommended approach to LST metrication formulated in this study cells for new components and subsystems to be designed in metric-module dimensions, but U.S. customary practice is allowed where U.S. metric standards and metric components are not available or would be unsuitable. Electrical/electronic-system design, which is presently largely metric, is considered exempt from futher metrication. An important guideline is that metric design and fabrication should in no way compromise the effectiveness of the LST equipment.

  8. The effect of climate–carbon cycle feedbacks on emission metrics

    NASA Astrophysics Data System (ADS)

    Sterner, Erik O.; Johansson, Daniel J. A.

    2017-03-01

    The Climate–Carbon cycle Feedback (CCF) affects emission metric values. In the Fifth Assessment Report (AR5) of the Intergovernmental Panel on Climate Change metric values for Global Warming Potentials (GWP) and Global Temperature Potentials (GTP) are reported both with and without CCF for non-CO2 climate forcers, while CCF is always included for CO2. The estimation of CCF for non-CO2 climate forcers in AR5 is based on a linear feedback analysis. This study compares that approach with an explicit approach that uses a temperature dependent carbon cycle model. The key difference in the CCF results for non-CO2 climate forcers is that, with the approach used in AR5, a fraction of the CO2 signal induced by non-CO2 forcers will persist in the atmosphere basically forever, while, with the approach based on an explicit carbon cycle model, the atmospheric CO2 signal induced by non-CO2 forcers eventually vanishes. The differences in metric values between the two model approaches are within ±10% for all well-mixed greenhouse gases when the time horizon is limited to 100 yr or less, for both GWP and GTP. However, for long time horizons, such as 500 yr, metric values are substantially lower with the explicit CCF model than with the linear feedback approach, up to 30% lower for GWP and up to 90% lower for GTP.

  9. Using Growth Models to Monitor School Performance: Comparing the Effect of the Metric and the Assessment

    ERIC Educational Resources Information Center

    Goldschmidt, Pete; Choi, Kilchan; Martinez, Felipe; Novak, John

    2010-01-01

    This paper investigates whether inferences about school performance based on longitudinal models are consistent when different assessments and metrics are used as the basis for analysis. Using norm-referenced (NRT) and standards-based (SBT) assessment results from panel data of a large heterogeneous school district, we examine inferences based on…

  10. Effects of Stream and Elevation Resolution on Riparian Metrics and Restoration Identification

    EPA Science Inventory

    Even though riparian areas attenuate nutrients and sediments from agricultural runoff at the field scale, best management practices and locations for restoring riparian areas should be determined at watershed scales. Riparian metrics (e.g., percent forest within 100m of stream)...

  11. Effects of Stream and Elevation Resolution on Riparian Metrics and Restoration Identification

    EPA Science Inventory

    Even though riparian areas attenuate nutrients and sediments from agricultural runoff at the field scale, best management practices and locations for restoring riparian areas should be determined at watershed scales. Riparian metrics (e.g., percent forest within 100m of stream)...

  12. Effective detective quantum efficiency for two mammography systems: measurement and comparison against established metrics.

    PubMed

    Salvagnini, Elena; Bosmans, Hilde; Struelens, Lara; Marshall, Nicholas W

    2013-10-01

    The aim of this paper was to illustrate the value of the new metric effective detective quantum efficiency (eDQE) in relation to more established measures in the optimization process of two digital mammography systems. The following metrics were included for comparison against eDQE: detective quantum efficiency (DQE) of the detector, signal difference to noise ratio (SdNR), and detectability index (d') calculated using a standard nonprewhitened observer with eye filter. The two systems investigated were the Siemens MAMMOMAT Inspiration and the Hologic Selenia Dimensions. The presampling modulation transfer function (MTF) required for the eDQE was measured using two geometries: a geometry containing scattered radiation and a low scatter geometry. The eDQE, SdNR, and d' were measured for poly(methyl methacrylate) (PMMA) thicknesses of 20, 40, 60, and 70 mm, with and without the antiscatter grid and for a selection of clinically relevant target/filter (T/F) combinations. Figures of merit (FOMs) were then formed from SdNR and d' using the mean glandular dose as the factor to express detriment. Detector DQE was measured at energies covering the range of typical clinically used spectra. The MTF measured in the presence of scattered radiation showed a large drop at low spatial frequency compared to the low scatter method and led to a corresponding reduction in eDQE. The eDQE for the Siemens system at 1 mm(-1) ranged between 0.15 and 0.27, depending on T/F and grid setting. For the Hologic system, eDQE at 1 mm(-1) varied from 0.15 to 0.32, again depending on T/F and grid setting. The eDQE results for both systems showed that the grid increased the system efficiency for PMMA thicknesses of 40 mm and above but showed only small sensitivity to T/F setting. While results of the SdNR and d' based FOMs confirmed the eDQE grid position results, they were also more specific in terms of T/F selection. For the Siemens system at 20 mm PMMA, the FOMs indicated Mo/Mo (grid out) as

  13. Effective detective quantum efficiency for two mammography systems: Measurement and comparison against established metrics

    SciTech Connect

    Salvagnini, Elena; Bosmans, Hilde; Marshall, Nicholas W.; Struelens, Lara

    2013-10-15

    Purpose: The aim of this paper was to illustrate the value of the new metric effective detective quantum efficiency (eDQE) in relation to more established measures in the optimization process of two digital mammography systems. The following metrics were included for comparison against eDQE: detective quantum efficiency (DQE) of the detector, signal difference to noise ratio (SdNR), and detectability index (d′) calculated using a standard nonprewhitened observer with eye filter.Methods: The two systems investigated were the Siemens MAMMOMAT Inspiration and the Hologic Selenia Dimensions. The presampling modulation transfer function (MTF) required for the eDQE was measured using two geometries: a geometry containing scattered radiation and a low scatter geometry. The eDQE, SdNR, and d′ were measured for poly(methyl methacrylate) (PMMA) thicknesses of 20, 40, 60, and 70 mm, with and without the antiscatter grid and for a selection of clinically relevant target/filter (T/F) combinations. Figures of merit (FOMs) were then formed from SdNR and d′ using the mean glandular dose as the factor to express detriment. Detector DQE was measured at energies covering the range of typical clinically used spectra.Results: The MTF measured in the presence of scattered radiation showed a large drop at low spatial frequency compared to the low scatter method and led to a corresponding reduction in eDQE. The eDQE for the Siemens system at 1 mm{sup −1} ranged between 0.15 and 0.27, depending on T/F and grid setting. For the Hologic system, eDQE at 1 mm{sup −1} varied from 0.15 to 0.32, again depending on T/F and grid setting. The eDQE results for both systems showed that the grid increased the system efficiency for PMMA thicknesses of 40 mm and above but showed only small sensitivity to T/F setting. While results of the SdNR and d′ based FOMs confirmed the eDQE grid position results, they were also more specific in terms of T/F selection. For the Siemens system at 20 mm PMMA

  14. Characterizing social media metrics of scholarly papers: the effect of document properties and collaboration patterns.

    PubMed

    Haustein, Stefanie; Costas, Rodrigo; Larivière, Vincent

    2015-01-01

    A number of new metrics based on social media platforms--grouped under the term "altmetrics"--have recently been introduced as potential indicators of research impact. Despite their current popularity, there is a lack of information regarding the determinants of these metrics. Using publication and citation data from 1.3 million papers published in 2012 and covered in Thomson Reuters' Web of Science as well as social media counts from Altmetric.com, this paper analyses the main patterns of five social media metrics as a function of document characteristics (i.e., discipline, document type, title length, number of pages and references) and collaborative practices and compares them to patterns known for citations. Results show that the presence of papers on social media is low, with 21.5% of papers receiving at least one tweet, 4.7% being shared on Facebook, 1.9% mentioned on blogs, 0.8% found on Google+ and 0.7% discussed in mainstream media. By contrast, 66.8% of papers have received at least one citation. Our findings show that both citations and social media metrics increase with the extent of collaboration and the length of the references list. On the other hand, while editorials and news items are seldom cited, it is these types of document that are the most popular on Twitter. Similarly, while longer papers typically attract more citations, an opposite trend is seen on social media platforms. Finally, contrary to what is observed for citations, it is papers in the Social Sciences and humanities that are the most often found on social media platforms. On the whole, these findings suggest that factors driving social media and citations are different. Therefore, social media metrics cannot actually be seen as alternatives to citations; at most, they may function as complements to other type of indicators.

  15. Characterizing Social Media Metrics of Scholarly Papers: The Effect of Document Properties and Collaboration Patterns

    PubMed Central

    Haustein, Stefanie; Costas, Rodrigo; Larivière, Vincent

    2015-01-01

    A number of new metrics based on social media platforms—grouped under the term “altmetrics”—have recently been introduced as potential indicators of research impact. Despite their current popularity, there is a lack of information regarding the determinants of these metrics. Using publication and citation data from 1.3 million papers published in 2012 and covered in Thomson Reuters’ Web of Science as well as social media counts from Altmetric.com, this paper analyses the main patterns of five social media metrics as a function of document characteristics (i.e., discipline, document type, title length, number of pages and references) and collaborative practices and compares them to patterns known for citations. Results show that the presence of papers on social media is low, with 21.5% of papers receiving at least one tweet, 4.7% being shared on Facebook, 1.9% mentioned on blogs, 0.8% found on Google+ and 0.7% discussed in mainstream media. By contrast, 66.8% of papers have received at least one citation. Our findings show that both citations and social media metrics increase with the extent of collaboration and the length of the references list. On the other hand, while editorials and news items are seldom cited, it is these types of document that are the most popular on Twitter. Similarly, while longer papers typically attract more citations, an opposite trend is seen on social media platforms. Finally, contrary to what is observed for citations, it is papers in the Social Sciences and humanities that are the most often found on social media platforms. On the whole, these findings suggest that factors driving social media and citations are different. Therefore, social media metrics cannot actually be seen as alternatives to citations; at most, they may function as complements to other type of indicators. PMID:25780916

  16. Distinguishing the effects of habitat degradation and pesticide stress on benthic invertebrates using stressor-specific metrics.

    PubMed

    von der Ohe, Peter Carsten; Goedkoop, Willem

    2013-02-01

    Hydromorphological degradation is a well known stressor for running waters, while the effects of elevated levels of pesticides are widely ignored. Hence, distinguishing between the effects of these two stressors is an urgent task for water managers that aim at appropriate remediation measures. We used a large monitoring data set on benthic invertebrates, habitat descriptors, and physico-chemical variables to develop the SPEAR[%](habitat) metric that indicates the effects of in-stream habitat degradation. SPEAR[%](habitat) correlated significantly with the habitat degradation score (HDS; based on substratum and vegetation coverage), while it did not respond to any physico-chemical variables (r(2)=0.20). This relationship improved for streams with low modeled pesticide inputs (r(2)=0.33), and improved even further for a subset of streams dominated by soft-bottom substrata, i.e. for similar stream-types (r(2)=0.65). These relationships were confirmed for an independent dataset that was not used in the derivation of the HDS (r(2)=0.57 and r(2)=0.65, respectively). These findings show that the SPEAR[%](habitat) had a high degree of specificity for the effects of habitat degradation. Conversely, neither the commonly used EPT and ASPT metrics, nor the German Fauna Index or SPEAR[%](pesticides) showed significant relationships with HDS. These metrics instead correlated significantly with the run-off potential (RP), a proxy of pesticide contamination of streams. Similarly, RP was also the most important explanatory variable for SPEAR[%](pesticides), followed by alkalinity and the number of forested upstream stretches (r(2)=0.61). The latter are expected to alleviate pesticide effects, as indicated by higher SPEAR[%](pesticides) values. These findings show that an integrated analysis of the two stressor-specific SPEAR-metrics in combination with the metrics of general ecological degradation can help water managers to distinguish between the effects of habitat degradation and

  17. The effect of metrics-based feedback on acquisition of sonographic skills relevant to performance of ultrasound-guided axillary brachial plexus block.

    PubMed

    Ahmed, O M A; Niessen, T; O'Donnell, B D; Gallagher, A G; Breslin, D S; DunnGalvin, A; Shorten, G D

    2017-09-01

    The objective of this study was to examine the effect of metrics-based vs. non-metrics-based feedback on novices learning predefined competencies for acquisition and interpretation of sonographic images relevant to performance of ultrasound-guided axillary brachial plexus block. Twelve anaesthetic trainees were randomly assigned to either metrics-based-feedback or non-metrics-based feedback groups. After a common learning phase, all participants attempted to perform a predefined task that involved scanning the left axilla of a single volunteer. Following completion of the task, all participants in each group received feedback from a different expert in regional blocks (consultant anaesthetist) and were allowed to practise the predefined task for up to 1 h. Those in the metrics-based feedback group received feedback based on previously validated metrics, and they practised each metric item until it was performed satisfactorily, as assessed by the supervising consultant. Subsequently, each participant attempted to perform ultrasonography of the left axilla on the same volunteer. Two trained consultant anaesthetists independently scored the video recording pre- and post-feedback scans using the validated metrics list. Both groups showed improvement from pre-feedback to post-feedback scores. Compared with participants in the non-metrics-based feedback group, those in the metrics-based feedback group completed more steps: median (IQR [range]) 18.8 (1.5 [17-20]) vs. 14.3 (4.5 [11-18.5]), p = 0.009, and made fewer errors 0.5 (1 [0-1.5]) vs. 1.5 (2 [1-6]), p = 0.041 postfeedback. In this study, novices' sonographic skills showed greater improvement when feedback was combined with validated metrics. © 2017 The Association of Anaesthetists of Great Britain and Ireland.

  18. The International Safeguards Technology Base: How is the Patient Doing? An Exploration of Effective Metrics

    SciTech Connect

    Schanfein, Mark J; Gouveia, Fernando S

    2010-07-01

    The term “Technology Base” is commonly used but what does it mean? Is there a common understanding of the components that comprise a technology base? Does a formal process exist to assess the health of a given technology base? These are important questions the relevance of which is even more pressing given the USDOE/NNSA initiatives to strengthen the safeguards technology base through investments in research & development and human capital development. Accordingly, the authors will establish a high-level framework to define and understand what comprises a technology base. Potential goal-driven metrics to assess the health of a technology base will also be explored, such as linear demographics and resource availability, in the hope that they can be used to better understand and improve the health of the U.S. safeguards technology base. Finally, through the identification of such metrics, the authors will offer suggestions and highlight choices for addressing potential shortfalls.

  19. Effects of metric and harmonic rhythm on the detection of pitch alterations in melodic sequences.

    PubMed

    Smith, K C; Cuddy, L L

    1989-08-01

    Tested response time to alterations. Metric rhythm and harmonic rhythm of 13-note tonal sequences were either matched or mismatched. Metric rhythm (3/4 or 4/4 meter) was induced by dynamic accents. Harmonic rhythm was induced by implied chord progressions initiated on the first note and on either every third or every fourth note. Responses were not always faster for matched rhythms or for alterations occurring on the dynamic accent. Responses were consistently faster for sequences presented in 4/4 meter. Musically untrained Ss performed similarly to trained Ss, but were slower and more variable. Accuracy of recall on a music dictation task also favored 4/4 meter rather than matched rhythms. Coding of pitch content may have been facilitated by the structural framework of 4/4 meter rather than by expectancies arising from the match of temporal and pitch organization.

  20. Navy Needs to Establish Effective Metrics to Achieve Desired Outcomes for SPY1 Radar Sustainment (Redacted)

    DTIC Science & Technology

    2016-08-01

    performance and costs to assess operational readiness; • review the PBL performance metrics that we determined were not adequate; and • assess whether the...Navy’s AN/SPY-1 Phased Array Radar (SPY-1 radar) performance-based logistics ( PBL ) contracts appropriately incentivized the support contractors...Arrangements The DoD designated performance-based logistics ( PBL ) as the preferred equipment sustainment strategy in an effort to increase weapon

  1. Wave function of the Universe, preferred reference frame effects and metric signature transition

    NASA Astrophysics Data System (ADS)

    Ghaffarnejad, Hossein

    2015-09-01

    Gravitational model of non-minimally coupled Brans Dicke (BD) scalar field 0 with dynamical unit time-like four vector field is used to study flat Robertson Walker (RW) cosmology in the presence of variable cosmological parameter V (ϕ) = Λϕ. Aim of the paper is to seek cosmological models which exhibit metric signature transition. The problem is studied in both classical and quantum cosmological approach with large values of BD parameter ω >> 1. Scale factor of RW metric is obtained as which describes nonsingular inflationary universe in Lorentzian signature sector. Euclidean signature sector of our solution describes a re-collapsing universe and is obtained from analytic continuation of the Lorentzian sector by exchanging . Dynamical vector field together with the BD scalar field are treated as fluid with time dependent barotropic index. They have regular (dark) matter dominance in the Euclidean (Lorentzian) sector. We solved Wheeler De Witt (WD) quantum wave equation of the cosmological system. Assuming a discrete non-zero ADM mass we obtained solutions of the WD equation as simple harmonic quantum Oscillator eigen functionals described by Hermite polynomials. Absolute values of these eigen functionals have nonzero values on the hypersurface in which metric field has signature degeneracy. Our eigen functionals describe nonzero probability of the space time with Lorentzian (Euclidean) signature for . Maximal probability corresponds to the ground state j = 0.

  2. Handbook of aircraft noise metrics

    NASA Technical Reports Server (NTRS)

    Bennett, R. L.; Pearsons, K. S.

    1981-01-01

    Information is presented on 22 noise metrics that are associated with the measurement and prediction of the effects of aircraft noise. Some of the instantaneous frequency weighted sound level measures, such as A-weighted sound level, are used to provide multiple assessment of the aircraft noise level. Other multiple event metrics, such as day-night average sound level, were designed to relate sound levels measured over a period of time to subjective responses in an effort to determine compatible land uses and aid in community planning. The various measures are divided into: (1) instantaneous sound level metrics; (2) duration corrected single event metrics; (3) multiple event metrics; and (4) speech communication metrics. The scope of each measure is examined in terms of its: definition, purpose, background, relationship to other measures, calculation method, example, equipment, references, and standards.

  3. Probing the post-newtonian physics of semi-conservative metric theories through secular tidal effects in satellite gradiometry missions

    NASA Astrophysics Data System (ADS)

    Qiang, Li-E.; Xu, Peng

    2016-04-01

    The existence of relativistic secular tidal effects along orbit motions will largely improve the measurement accuracies of relativistic gravitational gradients with orbiting gradiometers. With the continuous advances in technologies related to gradiometry and the improvements in their resolutions, it is feasible for future satellite gradiometry missions to carry out precision relativistic experiments and impose constraints on modern theories of gravity. In this work, we study the theoretical principles of measuring directly the secular post-Newtonian (PN) tidal effects in semi-conservative metric theories with satellite gradiometry missions. The isolations of the related PN parameters in the readouts of an orbiting three-axis gradiometer is discussed.

  4. Prediction of junior faculty success in biomedical research: comparison of metrics and effects of mentoring programs.

    PubMed

    von Bartheld, Christopher S; Houmanfar, Ramona; Candido, Amber

    2015-01-01

    Measuring and predicting the success of junior faculty is of considerable interest to faculty, academic institutions, funding agencies and faculty development and mentoring programs. Various metrics have been proposed to evaluate and predict research success and impact, such as the h-index, and modifications of this index, but they have not been evaluated and validated side-by-side in a rigorous empirical study. Our study provides a retrospective analysis of how well bibliographic metrics and formulas (numbers of total, first- and co-authored papers in the PubMed database, numbers of papers in high-impact journals) would have predicted the success of biomedical investigators (n = 40) affiliated with the University of Nevada, Reno, prior to, and after completion of significant mentoring and research support (through funded Centers of Biomedical Research Excellence, COBREs), or lack thereof (unfunded COBREs), in 2000-2014. The h-index and similar indices had little prognostic value. Publishing as mid- or even first author in only one high-impact journal was poorly correlated with future success. Remarkably, junior investigators with >6 first-author papers within 10 years were significantly (p < 0.0001) more likely (93%) to succeed than those with ≤6 first-author papers (4%), regardless of the journal's impact factor. The benefit of COBRE-support increased the success rate of junior faculty approximately 3-fold, from 15% to 47%. Our work defines a previously neglected set of metrics that predicted the success of junior faculty with high fidelity-thus defining the pool of faculty that will benefit the most from faculty development programs such as COBREs.

  5. The effect of supine versus upright patient positioning on inferior vena cava metrics.

    PubMed

    Panebianco, Nova L; Shofer, Frances; Cheng, Alfred; Fischer, Jonathan; Cody, Kenneth; Dean, Anthony J

    2014-11-01

    Ultrasound of the inferior vena cava (IVC) is a noninvasive and rapidly obtainable method of intravascular volume assessment; however not all patients can lie supine for this procedure. In this study we assess whether patient positioning affects IVC diameter metrics. This was a prospective convenience sample of patients in an in-patient dialysis unit at an urban tertiary care center. IVC metrics taken in the supine patient, and then at 45o semi-upright position, pre and post dialysis. Measurements were taken in M-mode in longitudinal plane roughly 2 cm below the level of the diaphragm. IVC-maximum and IVC-minimum diameter measurements were used to determine the IVC collapse index (IVC Max - IVC Min)/IVC Max). Statistics such as means, frequencies and percentages, intraclass correlation coefficient and Bland Altman summary statistics were calculated. Forty-five patients were enrolled. Average age was 57 years, 69% were male, 73% were African American, 82% had hypertension, 42% had diabetes. There was good to excellent agreement between supine and upright IVC measurements. Both the IVC minimum and maximum measurements had similar coefficient correlation (ri) measurements (0.917 and 0.890 respectively), whereas agreement in the collapse index was lower (ri = 0.813). Bland Altman analysis demonstrated excellent agreement and small 95% limits of agreement (±6 mm) with minimal mean bias for both the minimum and maximum measurements. IVC metrics do not change significantly based on patient position. For those patients who are unable to lay completely supine, a semi-upright measurement of the IVC for volume status may be an accurate alternative. Copyright © 2014 Elsevier Inc. All rights reserved.

  6. The anxiolytic effects of resistance exercise

    PubMed Central

    Strickland, Justin C.; Smith, Mark A.

    2014-01-01

    Numerous studies have revealed the beneficial effects of regular exercise across a variety of mental health measures. Although a great deal of attention has been paid to the role of aerobic exercise, less is known about the role of resistance exercise (i.e., strength training) in mental health outcomes. Resistance exercise includes a broad group of procedures that evoke repeated muscle action against resistances above those encountered in daily life. A growing body of literature has identified anxiolytic effects of resistance exercise in human populations after both single-bout sessions and long-term training. This research has shown that resistance training at a low-to-moderate intensity (<70% 1 repetition maximum) produces the most reliable and robust decreases in anxiety. Importantly, anxiolytic effects have been observed across a diverse range of populations and dependent measures. These findings provide support for the use of resistance exercise in the clinical management of anxiety. PMID:25071694

  7. The metric system: An introduction

    SciTech Connect

    Lumley, S.M.

    1995-05-01

    On July 13, 1992, Deputy Director Duane Sewell restated the Laboratory`s policy on conversion to the metric system which was established in 1974. Sewell`s memo announced the Laboratory`s intention to continue metric conversion on a reasonable and cost effective basis. Copies of the 1974 and 1992 Administrative Memos are contained in the Appendix. There are three primary reasons behind the Laboratory`s conversion to the metric system. First, Public Law 100-418, passed in 1988, states that by the end of fiscal year 1992 the Federal Government must begin using metric units in grants, procurements, and other business transactions. Second, on July 25, 1991, President George Bush signed Executive Order 12770 which urged Federal agencies to expedite conversion to metric units. Third, the contract between the University of California and the Department of Energy calls for the Laboratory to convert to the metric system. Thus, conversion to the metric system is a legal requirement and a contractual mandate with the University of California. Public Law 100-418 and Executive Order 12770 are discussed in more detail later in this section, but first they examine the reasons behind the nation`s conversion to the metric system. The second part of this report is on applying the metric system.

  8. The metric system: An introduction

    NASA Astrophysics Data System (ADS)

    Lumley, Susan M.

    On 13 Jul. 1992, Deputy Director Duane Sewell restated the Laboratory's policy on conversion to the metric system which was established in 1974. Sewell's memo announced the Laboratory's intention to continue metric conversion on a reasonable and cost effective basis. Copies of the 1974 and 1992 Administrative Memos are contained in the Appendix. There are three primary reasons behind the Laboratory's conversion to the metric system. First, Public Law 100-418, passed in 1988, states that by the end of fiscal year 1992 the Federal Government must begin using metric units in grants, procurements, and other business transactions. Second, on 25 Jul. 1991, President George Bush signed Executive Order 12770 which urged Federal agencies to expedite conversion to metric units. Third, the contract between the University of California and the Department of Energy calls for the Laboratory to convert to the metric system. Thus, conversion to the metric system is a legal requirement and a contractual mandate with the University of California. Public Law 100-418 and Executive Order 12770 are discussed in more detail later in this section, but first they examine the reasons behind the nation's conversion to the metric system. The second part of this report is on applying the metric system.

  9. Conversion to the Metric System

    ERIC Educational Resources Information Center

    Crunkilton, John C.; Lee, Jasper S.

    1974-01-01

    The authors discuss background information about the metric system and explore the effect of metrication of agriculture in areas such as equipment calibration, chemical measurement, and marketing of agricultural products. Suggestions are given for possible leadership roles and approaches that agricultural education might take in converting to the…

  10. Quality metrics for product defectiveness at KCD

    SciTech Connect

    Grice, J.V.

    1993-07-01

    Metrics are discussed for measuring and tracking product defectiveness at AlliedSignal Inc., Kansas City Division (KCD). Three new metrics, the metric (percent defective) that preceded the new metrics, and several alternatives are described. The new metrics, Percent Parts Accepted, Percent Parts Accepted Trouble Free, and Defects Per Million Observations, (denoted by PPA, PATF, and DPMO, respectively) were implemented for KCD-manufactured product and purchased material in November 1992. These metrics replace the percent defective metric that had been used for several years. The PPA and PATF metrics primarily measure quality performance while DPMO measures the effects of continuous improvement activities. The new metrics measure product quality in terms of product defectiveness observed only during the inspection process. The metrics were originally developed for purchased product and were adapted to manufactured product to provide a consistent set of metrics plant- wide. The new metrics provide a meaningful tool to measure the quantity of product defectiveness in terms of the customer`s requirements and expectations for quality. Many valid metrics are available and all will have deficiencies. These three metrics are among the least sensitive to problems and are easily understood. They will serve as good management tools for KCD in the foreseeable future until new flexible data systems and reporting procedures can be implemented that can provide more detailed and accurate metric computations.

  11. The effects of immediate achievement and retention of middle school students involved in a metric unit designed to promote the development of estimating skills

    NASA Astrophysics Data System (ADS)

    Jones, Michael L.; Rowsey, Robert E.

    1990-12-01

    Three hundred nintey-seven seventh-grade students were studied to determine the effect on immediate achievement and retention of a unit designed to promote the development of estimating skills involved in metric measurement. The study involved five teachers with a total of 15 average- or advanced-level classes divided into the reference and treatment groups. A five-day metric unit was designed so that both groups received exactly the same instruction in metric length, mass, and capacity with the exception of the treatment group's participation in activities relating to the development of estimation skills. Data collected from the Metric Application Instrument and analyzed with analysis of covariance indicated that students in the experimental group did retain significantly more of their improved metric application skills than the students in the reference group. The analysis of the main effects of race, sex, and ability indicated that white students achieved significantly more than black students and that males achieved significantly more than females. Analysis of significant race/ability and sex/race interactions indicated that (a) white students in the advanced group attained significantly greater achievement in metric application skills than black students of equal status and (b) white males significantly retained their metric applications achievement when compared to black males or black or white females.

  12. Clinical metric and medication persistency effects: evidence from a Medicaid care management program.

    PubMed

    Berg, Gregory D; Leary, Fredric; Medina, Wendie; Donnelly, Shawn; Warnick, Kathleen

    2015-02-01

    The objective was to estimate clinical metric and medication persistency impacts of a care management program. The data sources were Medicaid administrative claims for a sample population of 32,334 noninstitutionalized Medicaid-only aged, blind, or disabled patients with diagnosed conditions of asthma, coronary artery disease, chronic obstructive pulmonary disease, diabetes, or heart failure between 2005 and 2009. Multivariate regression analysis was used to test the hypothesis that exposure to a care management intervention increased the likelihood of having the appropriate medication or procedures performed, as well as increased medication persistency. Statistically significant clinical metric improvements occurred in each of the 5 conditions studied. Increased medication persistency was found for beta-blocker medication for members with coronary artery disease, angiotensin-converting enzyme inhibitor/angiotensin receptor blocker and diuretic medications for members with heart failure, bronchodilator and corticosteroid medications for members with chronic obstructive pulmonary disease, and aspirin/antiplatelet medications for members with diabetes. This study demonstrates that a care management program increases the likelihood of having an appropriate medication dispensed and/or an appropriate clinical test performed, as well as increased likelihood of medication persistency, in people with chronic conditions.

  13. Make It Metric.

    ERIC Educational Resources Information Center

    Camilli, Thomas

    Measurement is perhaps the most frequently used form of mathematics. This book presents activities for learning about the metric system designed for upper intermediate and junior high levels. Discussions include: why metrics, history of metrics, changing to a metric world, teaching tips, and formulas. Activities presented are: metrics all around…

  14. Engineering performance metrics

    NASA Astrophysics Data System (ADS)

    Delozier, R.; Snyder, N.

    1993-03-01

    Implementation of a Total Quality Management (TQM) approach to engineering work required the development of a system of metrics which would serve as a meaningful management tool for evaluating effectiveness in accomplishing project objectives and in achieving improved customer satisfaction. A team effort was chartered with the goal of developing a system of engineering performance metrics which would measure customer satisfaction, quality, cost effectiveness, and timeliness. The approach to developing this system involved normal systems design phases including, conceptual design, detailed design, implementation, and integration. The lessons teamed from this effort will be explored in this paper. These lessons learned may provide a starting point for other large engineering organizations seeking to institute a performance measurement system accomplishing project objectives and in achieving improved customer satisfaction. To facilitate this effort, a team was chartered to assist in the development of the metrics system. This team, consisting of customers and Engineering staff members, was utilized to ensure that the needs and views of the customers were considered in the development of performance measurements. The development of a system of metrics is no different than the development of any type of system. It includes the steps of defining performance measurement requirements, measurement process conceptual design, performance measurement and reporting system detailed design, and system implementation and integration.

  15. The effect of saccade metrics on the corollary discharge contribution to perceived eye location

    PubMed Central

    Bansal, Sonia; Jayet Bray, Laurence C.; Peterson, Matthew S.

    2015-01-01

    Corollary discharge (CD) is hypothesized to provide the movement information (direction and amplitude) required to compensate for the saccade-induced disruptions to visual input. Here, we investigated to what extent these conveyed metrics influence perceptual stability in human subjects with a target-displacement detection task. Subjects made saccades to targets located at different amplitudes (4°, 6°, or 8°) and directions (horizontal or vertical). During the saccade, the target disappeared and then reappeared at a shifted location either in the same direction or opposite to the movement vector. Subjects reported the target displacement direction, and from these reports we determined the perceptual threshold for shift detection and estimate of target location. Our results indicate that the thresholds for all amplitudes and directions generally scaled with saccade amplitude. Additionally, subjects on average produced hypometric saccades with an estimated CD gain <1. Finally, we examined the contribution of different error signals to perceptual performance, the saccade error (movement-to-movement variability in saccade amplitude) and visual error (distance between the fovea and the shifted target location). Perceptual judgment was not influenced by the fluctuations in movement amplitude, and performance was largely the same across movement directions for different magnitudes of visual error. Importantly, subjects reported the correct direction of target displacement above chance level for very small visual errors (<0.75°), even when these errors were opposite the target-shift direction. Collectively, these results suggest that the CD-based compensatory mechanisms for visual disruptions are highly accurate and comparable for saccades with different metrics. PMID:25761955

  16. [Effective coverage of health interventions in Latin America and the Caribbean: metrics for the assessment of health systems performance].

    PubMed

    Martínez, Sandra; Carrasquilla, Gabriel; Guerrero, Ramiro; Gómez-Dantés, Héctor; Castro, Victoria; Arreola-Ornelas, Héctor; Bedregal, Paula

    2011-01-01

    To measure effective coverage for ll health interventions in Latin America including the children's, women's and adult health, as part of program evaluation. Interventions were selected; the definitions and calculation methods were harmonized according to the information available to ensure comparability between countries. Chile has better indicators of crude and effective coverage followed by Mexico and Colombia.There are significant gaps between regions, counties or states. The health metric on effective coverage is a sensitive indicator that links three important aspects: Coverage of health interventions, use of health services, and access to such services. Effective coverage is a good tool to evaluate health programs performance, and also provides data of where and to whom the system should address national efforts and resources to achieve the purposes and goals set.

  17. NASA metrication activities

    NASA Technical Reports Server (NTRS)

    Vlannes, P. N.

    1978-01-01

    NASA's organization and policy for metrification, history from 1964, NASA participation in Federal agency activities, interaction with nongovernmental metrication organizations, and the proposed metrication assessment study are reviewed.

  18. Software Quality Assurance Metrics

    NASA Technical Reports Server (NTRS)

    McRae, Kalindra A.

    2004-01-01

    Software Quality Assurance (SQA) is a planned and systematic set of activities that ensures conformance of software life cycle processes and products conform to requirements, standards and procedures. In software development, software quality means meeting requirements and a degree of excellence and refinement of a project or product. Software Quality is a set of attributes of a software product by which its quality is described and evaluated. The set of attributes includes functionality, reliability, usability, efficiency, maintainability, and portability. Software Metrics help us understand the technical process that is used to develop a product. The process is measured to improve it and the product is measured to increase quality throughout the life cycle of software. Software Metrics are measurements of the quality of software. Software is measured to indicate the quality of the product, to assess the productivity of the people who produce the product, to assess the benefits derived from new software engineering methods and tools, to form a baseline for estimation, and to help justify requests for new tools or additional training. Any part of the software development can be measured. If Software Metrics are implemented in software development, it can save time, money, and allow the organization to identify the caused of defects which have the greatest effect on software development. The summer of 2004, I worked with Cynthia Calhoun and Frank Robinson in the Software Assurance/Risk Management department. My task was to research and collect, compile, and analyze SQA Metrics that have been used in other projects that are not currently being used by the SA team and report them to the Software Assurance team to see if any metrics can be implemented in their software assurance life cycle process.

  19. Software Quality Assurance Metrics

    NASA Technical Reports Server (NTRS)

    McRae, Kalindra A.

    2004-01-01

    Software Quality Assurance (SQA) is a planned and systematic set of activities that ensures conformance of software life cycle processes and products conform to requirements, standards and procedures. In software development, software quality means meeting requirements and a degree of excellence and refinement of a project or product. Software Quality is a set of attributes of a software product by which its quality is described and evaluated. The set of attributes includes functionality, reliability, usability, efficiency, maintainability, and portability. Software Metrics help us understand the technical process that is used to develop a product. The process is measured to improve it and the product is measured to increase quality throughout the life cycle of software. Software Metrics are measurements of the quality of software. Software is measured to indicate the quality of the product, to assess the productivity of the people who produce the product, to assess the benefits derived from new software engineering methods and tools, to form a baseline for estimation, and to help justify requests for new tools or additional training. Any part of the software development can be measured. If Software Metrics are implemented in software development, it can save time, money, and allow the organization to identify the caused of defects which have the greatest effect on software development. The summer of 2004, I worked with Cynthia Calhoun and Frank Robinson in the Software Assurance/Risk Management department. My task was to research and collect, compile, and analyze SQA Metrics that have been used in other projects that are not currently being used by the SA team and report them to the Software Assurance team to see if any metrics can be implemented in their software assurance life cycle process.

  20. Quantum correlations for the metric

    NASA Astrophysics Data System (ADS)

    Wetterich, C.

    2017-06-01

    We discuss the correlation function for the metric for homogeneous and isotropic cosmologies. The exact propagator equation determines the correlation function as the inverse of the second functional derivative of the quantum effective action. This formulation relates the metric correlation function employed in quantum gravity computations to cosmological observables as the graviton power spectrum. In the Einstein-Hilbert approximation for the effective action the on-shell graviton correlation function can be obtained equivalently from a product of mode functions which are solutions of the linearized Einstein equations. In contrast, the product of mode functions, often employed in the context of cosmology, does not yield the correlation function for the vector and scalar components of the metric fluctuations. We divide the metric fluctuations into "physical fluctuations," which couple to a conserved energy momentum tensor, and gauge fluctuations. On the subspace of physical metric fluctuations the relation to physical sources becomes invertible, such that the effective action and its relation to correlation functions no longer needs to involve a gauge fixing term. The physical metric fluctuations have a similar status as the Bardeen potentials, while being formulated in a covariant way. We compute the effective action for the physical metric fluctuations for geometries corresponding to realistic cosmologies.

  1. Novel dose metric for apparent cytotoxicity effects generated by in vitro cell exposure to silica nanoparticles.

    PubMed

    Wittmaack, Klaus

    2011-02-18

    This study aimed at identifying the dose metric applicable to studies on the viability of cells exposed to nanoparticles (NPs) in vitro. A previously reported set of data was evaluated very carefully. The extent of cell death after 24-h exposure of three cell lines to suspended silica NPs (<30 nm) was quantified using four different viability/cytotoxicity assays. Data on NP uptake in cells after 6-h exposure were also reported. Evidence is provided that, in spite of the small size of the NPs, mass transport to the cells cannot be explained solely by diffusion. Gravitational settling must have contributed significantly, presumably as the result of the formation of large agglomerates. Appropriately adjusted response data, with typically 22 combinations of mass concentration and height of the medium for each cell line, could be integrated in universal diagrams, provided the dose was quoted in terms of the areal density of NP mass delivered to the cells. Loss of viability became observable only if cells were exposed to the equivalent of 1 to 5 closely packed layers of NPs; the dose required for complete cell death ranged between 4 and about 20 layers of NPs. The results suggest that the cell-death phenomena observed in the evaluated work and in many similar studies reported in the literature constitute a matter of cell overload with nanostructured matter. This finding also implies that the toxic potential of individual silicate NPs is very low. Strategies for the design of advanced future work are outlined.

  2. A Dynamic Testing Complexity Metric

    NASA Technical Reports Server (NTRS)

    Voas, Jeffrey

    1991-01-01

    This paper introduces a dynamic metric that is based on the estimated ability of a program to withstand the effects of injected "semantic mutants" during execution by computing the same function as if the semantic mutants had not been injected. Semantic mutants include: (1) syntactic mutants injected into an executing program and (2) randomly selected values injected into an executing program's internal states. The metric is a function of a program, the method used for injecting these two types of mutants, and the program's input distribution; this metric is found through dynamic executions of the program. A program's ability to withstand the effects of injected semantic mutants by computing the same function when executed is then used as a tool for predicting the difficulty that will be incurred during random testing to reveal the existence of faults, i.e., the metric suggests the likelihood that a program will expose the existence of faults during random testing assuming faults were to exist. If the metric is applied to a module rather than to a program, the metric can be used to guide the allocation of testing resources among a program's modules. In this manner the metric acts as a white-box testing tool for determining where to concentrate testing resources. Index Terms: Revealing ability, random testing, input distribution, program, fault, failure.

  3. Effectiveness of vegetation-based biodiversity offset metrics as surrogates for ants.

    PubMed

    Hanford, Jayne K; Crowther, Mathew S; Hochuli, Dieter F

    2017-02-01

    Biodiversity offset schemes are globally popular policy tools for balancing the competing demands of conservation and development. Trading currencies for losses and gains in biodiversity value at development and credit sites are usually based on several vegetation attributes combined to yield a simple score (multimetric), but the score is rarely validated prior to implementation. Inaccurate biodiversity trading currencies are likely to accelerate global biodiversity loss through unrepresentative trades of losses and gains. We tested a model vegetation multimetric (i.e., vegetation structural and compositional attributes) typical of offset trading currencies to determine whether it represented measurable components of compositional and functional biodiversity. Study sites were located in remnant patches of a critically endangered ecological community in western Sydney, Australia, an area representative of global conflicts between conservation and expanding urban development. We sampled ant fauna composition with pitfall traps and enumerated removal by ants of native plant seeds from artificial seed containers (seed depots). Ants are an excellent model taxon because they are strongly associated with habitat complexity, respond rapidly to environmental change, and are functionally important at many trophic levels. The vegetation multimetric did not predict differences in ant community composition or seed removal, despite underlying assumptions that biodiversity trading currencies used in offset schemes represent all components of a site's biodiversity value. This suggests that vegetation multimetrics are inadequate surrogates for total biodiversity value. These findings highlight the urgent need to refine existing offsetting multimetrics to ensure they meet underlying assumptions of surrogacy. Despite the best intentions, offset schemes will never achieve their goal of no net loss of biodiversity values if trades are based on metrics unrepresentative of total

  4. Effect of fensuccinal on experimental insulin resistance.

    PubMed

    Gorbenko, N I; Poltorak, V V; Gladkikh, A I; Ivanova, O V

    2000-07-01

    The effects of new antioxidant fensuccinal on dexamethasone-induced insulin resistance in rats were studied. Oral administration of fensuccinal in a dose of 25 mg/kg for 2 weeks prevented basal hyperinsulinemia and insulin insensitivity of peripheral tissues. Fensuccinal also attenuated oxidative stress by decreasing the concentrations of primary and secondary lipid peroxidation products in liver homogenates. The ability of fensuccinal to prevent dexamethasone-induced insulin resistance is probably due to its antioxidant properties.

  5. Aquatic Acoustic Metrics Interface

    SciTech Connect

    2012-12-18

    Fishes and marine mammals may suffer a range of potential effects from exposure to intense underwater sound generated by anthropogenic activities such as pile driving, shipping, sonars, and underwater blasting. Several underwater sound recording (USR) devices have been built to acquire samples of the underwater sound generated by anthropogenic activities. Software becomes indispensable for processing and analyzing the audio files recorded by these USRs. The new Aquatic Acoustic Metrics Interface Utility Software (AAMI) is specifically designed for analysis of underwater sound recordings to provide data in metrics that facilitate evaluation of the potential impacts of the sound on aquatic animals. In addition to the basic functions, such as loading and editing audio files recorded by USRs and batch processing of sound files, the software utilizes recording system calibration data to compute important parameters in physical units. The software also facilitates comparison of the noise sound sample metrics with biological measures such as audiograms of the sensitivity of aquatic animals to the sound, integrating various components into a single analytical frame.

  6. NASA metric transition plan

    NASA Technical Reports Server (NTRS)

    1992-01-01

    NASA science publications have used the metric system of measurement since 1970. Although NASA has maintained a metric use policy since 1979, practical constraints have restricted actual use of metric units. In 1988, an amendment to the Metric Conversion Act of 1975 required the Federal Government to adopt the metric system except where impractical. In response to Public Law 100-418 and Executive Order 12770, NASA revised its metric use policy and developed this Metric Transition Plan. NASA's goal is to use the metric system for program development and functional support activities to the greatest practical extent by the end of 1995. The introduction of the metric system into new flight programs will determine the pace of the metric transition. Transition of institutional capabilities and support functions will be phased to enable use of the metric system in flight program development and operations. Externally oriented elements of this plan will introduce and actively support use of the metric system in education, public information, and small business programs. The plan also establishes a procedure for evaluating and approving waivers and exceptions to the required use of the metric system for new programs. Coordination with other Federal agencies and departments (through the Interagency Council on Metric Policy) and industry (directly and through professional societies and interest groups) will identify sources of external support and minimize duplication of effort.

  7. NASA metric transition plan

    NASA Astrophysics Data System (ADS)

    NASA science publications have used the metric system of measurement since 1970. Although NASA has maintained a metric use policy since 1979, practical constraints have restricted actual use of metric units. In 1988, an amendment to the Metric Conversion Act of 1975 required the Federal Government to adopt the metric system except where impractical. In response to Public Law 100-418 and Executive Order 12770, NASA revised its metric use policy and developed this Metric Transition Plan. NASA's goal is to use the metric system for program development and functional support activities to the greatest practical extent by the end of 1995. The introduction of the metric system into new flight programs will determine the pace of the metric transition. Transition of institutional capabilities and support functions will be phased to enable use of the metric system in flight program development and operations. Externally oriented elements of this plan will introduce and actively support use of the metric system in education, public information, and small business programs. The plan also establishes a procedure for evaluating and approving waivers and exceptions to the required use of the metric system for new programs. Coordination with other Federal agencies and departments (through the Interagency Council on Metric Policy) and industry (directly and through professional societies and interest groups) will identify sources of external support and minimize duplication of effort.

  8. More Than Numbers: Effects of Social Media Virality Metrics on Intention to Help Unknown Others in the Context of Bone Marrow Donation.

    PubMed

    Lee-Won, Roselyn J; Abo, Melissa M; Na, Kilhoe; White, Tiffany N

    2016-06-01

    A bone marrow transplant is often the only key to recovery and survival for patients suffering from blood cancers. Social media platforms have allowed nonprofit organizations as well as family members and friends of patients in need of a matching donor to make their solicitation messages go viral and reach out to the broadest possible audience to increase the likelihood of finding a matching donor. Noting that social media audiences are exposed not only to the content of a social media message but also to the metrics representing the virality of the message (i.e., how many times the content has been shared), we conducted an online experiment to investigate the effects of virality metrics on perceived social norms and behavioral intention to join a bone marrow registry. In doing so, we considered the potential moderating role of perceived threat posed by blood cancers. The experiment was conducted with 152 participants who met the general eligibility guidelines set by the National Marrow Donor Program (NMDP). The results of the experiment showed that exposure to high virality metrics led to greater perceived injunctive norms. The results also revealed that the effect of virality metrics on perceived injunctive norms was significant among those perceiving low levels of blood cancer threat. Furthermore, the results demonstrated that high virality metrics led to greater intention to join a bone marrow registry through perceived injunctive norms only when perceived threat of blood cancers was low. Theoretical and practical implications of these findings are discussed.

  9. Multi-site Study of Diffusion Metric Variability: Characterizing the Effects of Site, Vendor, Field Strength, and Echo Time using the Histogram Distance

    PubMed Central

    Helmer, K. G.; Chou, M-C.; Preciado, R. I.; Gimi, B.; Rollins, N. K.; Song, A.; Turner, J.; Mori, S.

    2016-01-01

    MRI-based multi-site trials now routinely include some form of diffusion-weighted imaging (DWI) in their protocol. These studies can include data originating from scanners built by different vendors, each with their own set of unique protocol restrictions, including restrictions on the number of available gradient directions, whether an externally-generated list of gradient directions can be used, and restrictions on the echo time (TE). One challenge of multi-site studies is to create a common imaging protocol that will result in a reliable and accurate set of diffusion metrics. The present study describes the effect of site, scanner vendor, field strength, and TE on two common metrics: the first moment of the diffusion tensor field (mean diffusivity, MD), and the fractional anisotropy (FA). We have shown in earlier work that ROI metrics and the mean of MD and FA histograms are not sufficiently sensitive for use in site characterization. Here we use the distance between whole brain histograms of FA and MD to investigate within- and between-site effects. We concluded that the variability of DTI metrics due to site, vendor, field strength, and echo time could influence the results in multi-center trials and that histogram distance is sensitive metrics for each of these variables. PMID:27350723

  10. Object recognition using metric shape.

    PubMed

    Lee, Young-Lim; Lind, Mats; Bingham, Ned; Bingham, Geoffrey P

    2012-09-15

    Most previous studies of 3D shape perception have shown a general inability to visually perceive metric shape. In line with this, studies of object recognition have shown that only qualitative differences, not quantitative or metric ones can be used effectively for object recognition. Recently, Bingham and Lind (2008) found that large perspective changes (≥ 45°) allow perception of metric shape and Lee and Bingham (2010) found that this, in turn, allowed accurate feedforward reaches-to-grasp objects varying in metric shape. We now investigated whether this information would allow accurate and effective recognition of objects that vary in respect to metric shape. Both judgment accuracies (d') and reaction times confirmed that, with the availability of visual information in large perspective changes, recognition of objects using quantitative as compared to qualitative properties was equivalent in accuracy and speed of judgments. The ability to recognize objects based on their metric shape is, therefore, a function of the availability or unavailability of requisite visual information. These issues and results are discussed in the context of the Two Visual System hypothesis of Milner and Goodale (1995, 2006). 2012 Elsevier Ltd. All rights reserved

  11. FY 2011 4th Quarter Metric: Estimate of Future Aerosol Direct and Indirect Effects

    SciTech Connect

    Koch, D

    2011-09-21

    The global and annual mean aerosol direct and indirect effects, relative to 1850 conditions, estimated from CESM simulations are 0.02 W m-2 and -0.39 W m-2, respectively, for emissions in year 2100 under the IPCC RCP8.5 scenario. The indirect effect is much smaller than that for 2000 emissions because of much smaller SO2 emissions in 2100; the direct effects are small due to compensation between warming by black carbon and cooling by sulfate.

  12. Verification of metric theory of gravitation using beam width correction for Sagnac effect

    SciTech Connect

    Tan Weihan; Song Xiaojue; Gu Zhichong

    1983-10-01

    The effect of finite beam width on the Sagnac frequency shift has been calculated by Zhbairy and Scully. However, their analysis is somewhat incorrect. In the present paper, we point out the questions included in their article and give a new analysis on this subject and the corrected equations for Sagnac effect for square ring lasers.

  13. Moving to Metric.

    ERIC Educational Resources Information Center

    North Carolina State Dept. of Public Instruction, Raleigh.

    This booklet, designed to help the consumer prepare for the change to the metric system, discusses the following related topics: simplicity and universality of the metric system, weather, shopping, textiles, cooking, and driving. (MP)

  14. Companion's effects upon resistance to change.

    PubMed

    dos Santos, C V; Abreu-Rodrigues, J

    2008-10-01

    In order to investigate the effects of a companion's presence on resistance to change, five rats were trained under a multiple schedule comprised of components with high versus low rate of water reinforcement. After response rates became stable, water was given to the subjects prior to the experimental sessions, and these were conducted both in the absence and in the presence of a companion, which also could be responding or merely present. Results showed that the companion's presence increased resistance to satiation, mainly during the component with the higher reinforcement rate. These results suggest that the effect of the companion's presence may interact with reinforcement rate in determining response rate and resistance to satiation.

  15. How Robust Are Malaria Parasite Clearance Rates as Indicators of Drug Effectiveness and Resistance?

    PubMed Central

    Kay, Katherine

    2015-01-01

    Artemisinin-based combination therapies (ACTs) are currently the first-line drugs for treating uncomplicated falciparum malaria, the most deadly of the human malarias. Malaria parasite clearance rates estimated from patients' blood following ACT treatment have been widely adopted as a measure of drug effectiveness and as surveillance tools for detecting the presence of potential artemisinin resistance. This metric has not been investigated in detail, nor have its properties or potential shortcomings been identified. Herein, the pharmacology of drug treatment, parasite biology, and human immunity are combined to investigate the dynamics of parasite clearance following ACT. This approach parsimoniously recovers the principal clinical features and dynamics of clearance. Human immunity is the primary determinant of clearance rates, unless or until artemisinin killing has fallen to near-ineffective levels. Clearance rates are therefore highly insensitive metrics for surveillance that may lead to overconfidence, as even quite substantial reductions in drug sensitivity may not be detected as lower clearance rates. Equally serious is the use of clearance rates to quantify the impact of ACT regimen changes, as this strategy will plausibly miss even very substantial increases in drug effectiveness. In particular, the malaria community may be missing the opportunity to dramatically increase ACT effectiveness through regimen changes, particularly through a switch to twice-daily regimens and/or increases in artemisinin dosing levels. The malaria community therefore appears overreliant on a single metric of drug effectiveness, the parasite clearance rate, that has significant and serious shortcomings. PMID:26239987

  16. Metrication for the Manager.

    ERIC Educational Resources Information Center

    Benedict, John T.

    The scope of this book covers metrication management. It was created to fill the middle management need for condensed, authoritative information about the metrication process and was conceived as a working tool and a prime reference source. Written from a management point of view, it touches on virtually all aspects of metrication and highlights…

  17. Phylogenetic metrics of community similarity.

    PubMed

    Ives, Anthony R; Helmus, Matthew R

    2010-11-01

    We derive a new metric of community similarity that takes into account the phylogenetic relatedness among species. This metric, phylogenetic community dissimilarity (PCD), can be partitioned into two components, a nonphylogenetic component that reflects shared species between communities (analogous to Sørensen' s similarity metric) and a phylogenetic component that reflects the evolutionary relationships among nonshared species. Therefore, even if a species is not shared between two communities, it will increase the similarity of the two communities if it is phylogenetically related to species in the other community. We illustrate PCD with data on fish and aquatic macrophyte communities from 59 temperate lakes. Dissimilarity between fish communities associated with environmental differences between lakes often has a phylogenetic component, whereas this is not the case for macrophyte communities. With simulations, we then compare PCD with two other metrics of phylogenetic community similarity, II(ST) and UniFrac. Of the three metrics, PCD was best at identifying environmental drivers of community dissimilarity, showing lower variability and greater statistical power. Thus, PCD is a statistically powerful metric that separates the effects of environmental drivers on compositional versus phylogenetic components of community structure.

  18. Effecting Change in a Resistant Organization.

    ERIC Educational Resources Information Center

    Caldwell, Patricia F.; Gould, Edward

    In an effort to overcome organizational resistance to change, Victor Valley College, in Victorville, California, has utilized a seven-part strategy to enable leaders to empower others and effect change. Step 1 requires the development of a visionary plan, so that changes have a meaningful context. Step 2 calls for an assessment of the campus…

  19. Effective flow resistivity of highway pavements.

    PubMed

    Rochat, Judith L; Read, David R

    2013-12-01

    In the case of highway traffic noise, propagating sound is influenced by the ground over which it travels, whether it is the pavement itself or the ground between the highway and nearby communities. Properly accounting for ground type in modeling can increase accuracy in noise impact determinations and noise abatement design. Pavement-specific effective flow resistivity values are being investigated for inclusion in the Federal Highway Administration Traffic Noise Model, which uses these values in the sound propagation algorithms and currently applies a single effective flow resistivity value to all pavement. Pavement-specific effective flow resistivity values were obtained by applying a modified version of the American National Standards Institute S1.18 standard. The data analysis process was tailored to allow for increased sensitivity and extraction of effective flow resistivity values for a broad range of pavements (sound absorptive to reflective). For porous pavements (sound absorptive), it was determined that examination of the measured data can reveal influence from an underlying structure. Use of such techniques can aid in the design of quieter pavements.

  20. Using Social Network Metrics to Assess the Effectiveness of Broad Based Admission Practices

    ERIC Educational Resources Information Center

    Dawson, Shane; Macfadyen, Leah; Lockyer, Lori; Mazzochi-Jones, David

    2011-01-01

    Notions of what it is to be knowledgeable and skilled in one's profession have evolved in recent decades. For instance, medical practitioners are expected to think critically and creatively, communicate effectively, and to be a professional and community leader. While these attributes have always been well regarded, it is only relatively recently…

  1. Using Social Network Metrics to Assess the Effectiveness of Broad Based Admission Practices

    ERIC Educational Resources Information Center

    Dawson, Shane; Macfadyen, Leah; Lockyer, Lori; Mazzochi-Jones, David

    2011-01-01

    Notions of what it is to be knowledgeable and skilled in one's profession have evolved in recent decades. For instance, medical practitioners are expected to think critically and creatively, communicate effectively, and to be a professional and community leader. While these attributes have always been well regarded, it is only relatively recently…

  2. Chronic effects of temperature on mortality in the Southeastern USA using satellite-based exposure metrics

    NASA Astrophysics Data System (ADS)

    Shi, Liuhua; Liu, Pengfei; Wang, Yan; Zanobetti, Antonella; Kosheleva, Anna; Koutrakis, Petros; Schwartz, Joel

    2016-07-01

    Climate change may affect human health, particularly for elderly individuals who are vulnerable to temperature changes. While many studies have investigated the acute effects of heat, only a few have dealt with the chronic ones. We have examined the effects of seasonal temperatures on survival of the elderly in the Southeastern USA, where a large fraction of subpopulation resides. We found that both seasonal mean temperature and its standard deviation (SD) affected long-term survival among the 13 million Medicare beneficiaries (aged 65+) in this region during 2000–2013. A 1 °C increase in summer mean temperature corresponded to an increase of 2.5% in death rate. Whereas, 1 °C increase in winter mean temperature was associated with a decrease of 1.5%. Increases in seasonal temperature SD also influence mortality. We decomposed seasonal mean temperature and its temperature SD into long-term geographic contrasts between ZIP codes and annual anomalies within ZIP code. Effect modifications by different subgroups were also examined to find out whether certain individuals are more vulnerable. Our findings will be critical to future efforts assessing health risks related to the future climate change.

  3. Chronic effects of temperature on mortality in the Southeastern USA using satellite-based exposure metrics

    PubMed Central

    Shi, Liuhua; Liu, Pengfei; Wang, Yan; Zanobetti, Antonella; Kosheleva, Anna; Koutrakis, Petros; Schwartz, Joel

    2016-01-01

    Climate change may affect human health, particularly for elderly individuals who are vulnerable to temperature changes. While many studies have investigated the acute effects of heat, only a few have dealt with the chronic ones. We have examined the effects of seasonal temperatures on survival of the elderly in the Southeastern USA, where a large fraction of subpopulation resides. We found that both seasonal mean temperature and its standard deviation (SD) affected long-term survival among the 13 million Medicare beneficiaries (aged 65+) in this region during 2000–2013. A 1 °C increase in summer mean temperature corresponded to an increase of 2.5% in death rate. Whereas, 1 °C increase in winter mean temperature was associated with a decrease of 1.5%. Increases in seasonal temperature SD also influence mortality. We decomposed seasonal mean temperature and its temperature SD into long-term geographic contrasts between ZIP codes and annual anomalies within ZIP code. Effect modifications by different subgroups were also examined to find out whether certain individuals are more vulnerable. Our findings will be critical to future efforts assessing health risks related to the future climate change. PMID:27436237

  4. Substrate effect in chemically amplified resist

    NASA Astrophysics Data System (ADS)

    Mori, Shigeyasu; Watanabe, Takeo; Adachi, Kouichirou; Fukushima, Takashi; Uda, Keichiro; Sato, Yuichi

    1996-06-01

    SiN substrate effect in chemically amplified (CA) resist has been investigated by surface analysis and evaluating the pattern profile of CA negative tone resist. Fine profile can be replicated on SiN substrate treated with oxygen plasma optimized condition. Undercut profile can be affected by adsorbed materials on SiN substrate from thermal desorption spectroscopy (TDS) analysis results. From the results of electron spectroscopy for chemical analysis (ESCA), it is found that Si-N bonding is replaced to Si-O bonding while SiN substrate is treated with oxygen plasma. Relations between footing length and oxygen plasma treatment condition suggest that undercut profile due to the concentration of nitrogen on the surface of SiN substrate. At the interface between the SiN substrate and the CA resist, the SiN substrate works as base existing water, and quenches photo-generated-acids. The mechanism of substrate effect of SiN is clarified. Reducing the SiN-substrate effect by treating the surface with oxygen plasma, fine resist pattern without undercut and footing is formed on SiN substrate.

  5. Assessing treatment effects in clinical trials with the discan metric of the Sheehan Disability Scale.

    PubMed

    Sheehan, Kathy Harnett; Sheehan, David V

    2008-03-01

    The Sheehan Disability Scale (SDS) is a patient-rated, discretized analog measure of functional disability in work, social, and family life. Its increasing use in clinical trials in psychiatry suggests a need to assess its responsiveness and interpretability. In this paper we identify and review studies in which the SDS was used as a treatment outcome measure. Our objectives are (i) to evaluate the sensitivity of the SDS to treatment effects and (ii) to examine potential thresholds or cutoff scores for remission and response. Studies for the review were retrieved from the National Library of Medicine's PubMed database (1966 to 21 March 2007) and other sources. All studies had to use the SDS, be double-blind, controlled or large open-label trials in English. Studies assessing nonpharmacological treatments, long-term trials (>12 weeks), small n trials (less than 20 patients per treatment arm) and trials for conditions other than one of the anxiety disorders, depression, or premenstrual dysphoric disorder were excluded. Extracted data included the diagnostic target of treatment, n, study design, and method of analysis. Initial, endpoint and/or mean change scores were extracted from tables, text, or extrapolated from figures. In all, 37 studies meeting the inclusion criteria were retrieved and reviewed. All of the studies treated the SDS as a numeric scale and analyzed mean change or endpoint differences with parametric statistics. Three provided additional outcome data using nonparametric response or remission criteria. Overall, the SDS performed well in discriminating between active and inactive treatments. The results indicate that the SDS is sensitive to treatment effects. To establish reliable and valid cutoff scores for remission and response, there is a need to supplement parametric analyses using mean change and endpoint differences with nonparametric analyses showing the percentage meeting specified response and remission criteria. In addition, the percentages

  6. Multiple metrics of diversity have different effects on temperate forest functioning over succession.

    PubMed

    Yuan, Zuoqiang; Wang, Shaopeng; Gazol, Antonio; Mellard, Jarad; Lin, Fei; Ye, Ji; Hao, Zhanqing; Wang, Xugao; Loreau, Michel

    2016-12-01

    Biodiversity can be measured by taxonomic, phylogenetic, and functional diversity. How ecosystem functioning depends on these measures of diversity can vary from site to site and depends on successional stage. Here, we measured taxonomic, phylogenetic, and functional diversity, and examined their relationship with biomass in two successional stages of the broad-leaved Korean pine forest in northeastern China. Functional diversity was calculated from six plant traits, and aboveground biomass (AGB) and coarse woody productivity (CWP) were estimated using data from three forest censuses (10 years) in two large fully mapped forest plots (25 and 5 ha). 11 of the 12 regressions between biomass variables (AGB and CWP) and indices of diversity showed significant positive relationships, especially those with phylogenetic diversity. The mean tree diversity-biomass regressions increased from 0.11 in secondary forest to 0.31 in old-growth forest, implying a stronger biodiversity effect in more mature forest. Multi-model selection results showed that models including species richness, phylogenetic diversity, and single functional traits explained more variation in forest biomass than other candidate models. The models with a single functional trait, i.e., leaf area in secondary forest and wood density in mature forest, provided better explanations for forest biomass than models that combined all six functional traits. This finding may reflect different strategies in growth and resource acquisition in secondary and old-growth forests.

  7. Using Fish Population Metrics to Compare the Effects of Artificial Reef Density

    PubMed Central

    2015-01-01

    Artificial reefs continue to be added as habitat throughout the world, yet questions remain about how reef design affects fish diversity and abundance. In the present study, the effects of reef density were assessed for fish communities and sizes of economically valuable Lutjanus campechanus 13 km off Port Mansfield, Texas, at a reef composed of more than 4000 concrete culverts. The study spanned from May to June in 2013 and 2014, and sites sampled included natural reefs, bare areas, and varying culvert patch density categories, ranging from 1–190 culverts. Abundances of adults and species evenness of juvenile populations differed between the years. Fish communities did not significantly differ among density categories; however, highest species richness and total abundances were observed at intermediate culvert densities and at natural reefs. Whereas the abundance of L. campechanus did not differ among density categories, mean total lengths of L. campechanus were greatest at the lower density. Our findings suggest that reefs should be deployed with intermediate patch density of 71–120 culverts in a 30-m radius to yield the highest fish abundances. PMID:26422472

  8. Using Fish Population Metrics to Compare the Effects of Artificial Reef Density.

    PubMed

    Froehlich, Catheline Y M; Kline, Richard J

    2015-01-01

    Artificial reefs continue to be added as habitat throughout the world, yet questions remain about how reef design affects fish diversity and abundance. In the present study, the effects of reef density were assessed for fish communities and sizes of economically valuable Lutjanus campechanus 13 km off Port Mansfield, Texas, at a reef composed of more than 4000 concrete culverts. The study spanned from May to June in 2013 and 2014, and sites sampled included natural reefs, bare areas, and varying culvert patch density categories, ranging from 1-190 culverts. Abundances of adults and species evenness of juvenile populations differed between the years. Fish communities did not significantly differ among density categories; however, highest species richness and total abundances were observed at intermediate culvert densities and at natural reefs. Whereas the abundance of L. campechanus did not differ among density categories, mean total lengths of L. campechanus were greatest at the lower density. Our findings suggest that reefs should be deployed with intermediate patch density of 71-120 culverts in a 30-m radius to yield the highest fish abundances.

  9. Multi-site study of diffusion metric variability: effects of site, vendor, field strength, and echo time on regions-of-interest and histogram-bin analyses

    PubMed Central

    Helmer, K. G.; Chou, M-C.; Preciado, R. I.; Gimi, B.; Rollins, N. K.; Song, A.; Turner, J.; Mori, S.

    2016-01-01

    It is now common for magnetic-resonance-imaging (MRI) based multi-site trials to include diffusion-weighted imaging (DWI) as part of the protocol. It is also common for these sites to possess MR scanners of different manufacturers, different software and hardware, and different software licenses. These differences mean that scanners may not be able to acquire data with the same number of gradient amplitude values and number of available gradient directions. Variability can also occur in achievable b-values and minimum echo times. The challenge of a multi-site study then, is to create a common protocol by understanding and then minimizing the effects of scanner variability and identifying reliable and accurate diffusion metrics. This study describes the effect of site, scanner vendor, field strength, and TE on two diffusion metrics: the first moment of the diffusion tensor field (mean diffusivity, MD), and the fractional anisotropy (FA) using two common analyses (region-of-interest and mean-bin value of whole brain histograms). The goal of the study was to identify sources of variability in diffusion-sensitized imaging and their influence on commonly reported metrics. The results demonstrate that the site, vendor, field strength, and echo time all contribute to variability in FA and MD, though to different extent. We conclude that characterization of the variability of DTI metrics due to site, vendor, field strength, and echo time is a worthwhile step in the construction of multi-center trials. PMID:27330240

  10. Multi-site study of diffusion metric variability: effects of site, vendor, field strength, and echo time on regions-of-interest and histogram-bin analyses

    NASA Astrophysics Data System (ADS)

    Helmer, K. G.; Chou, M.-C.; Preciado, R. I.; Gimi, B.; Rollins, N. K.; Song, A.; Turner, J.; Mori, S.

    2016-03-01

    It is now common for magnetic-resonance-imaging (MRI) based multi-site trials to include diffusion-weighted imaging (DWI) as part of the protocol. It is also common for these sites to possess MR scanners of different manufacturers, different software and hardware, and different software licenses. These differences mean that scanners may not be able to acquire data with the same number of gradient amplitude values and number of available gradient directions. Variability can also occur in achievable b-values and minimum echo times. The challenge of a multi-site study then, is to create a common protocol by understanding and then minimizing the effects of scanner variability and identifying reliable and accurate diffusion metrics. This study describes the effect of site, scanner vendor, field strength, and TE on two diffusion metrics: the first moment of the diffusion tensor field (mean diffusivity, MD), and the fractional anisotropy (FA) using two common analyses (region-of-interest and mean-bin value of whole brain histograms). The goal of the study was to identify sources of variability in diffusion-sensitized imaging and their influence on commonly reported metrics. The results demonstrate that the site, vendor, field strength, and echo time all contribute to variability in FA and MD, though to different extent. We conclude that characterization of the variability of DTI metrics due to site, vendor, field strength, and echo time is a worthwhile step in the construction of multi-center trials.

  11. Algebraic mesh quality metrics

    SciTech Connect

    KNUPP,PATRICK

    2000-04-24

    Quality metrics for structured and unstructured mesh generation are placed within an algebraic framework to form a mathematical theory of mesh quality metrics. The theory, based on the Jacobian and related matrices, provides a means of constructing, classifying, and evaluating mesh quality metrics. The Jacobian matrix is factored into geometrically meaningful parts. A nodally-invariant Jacobian matrix can be defined for simplicial elements using a weight matrix derived from the Jacobian matrix of an ideal reference element. Scale and orientation-invariant algebraic mesh quality metrics are defined. the singular value decomposition is used to study relationships between metrics. Equivalence of the element condition number and mean ratio metrics is proved. Condition number is shown to measure the distance of an element to the set of degenerate elements. Algebraic measures for skew, length ratio, shape, volume, and orientation are defined abstractly, with specific examples given. Combined metrics for shape and volume, shape-volume-orientation are algebraically defined and examples of such metrics are given. Algebraic mesh quality metrics are extended to non-simplical elements. A series of numerical tests verify the theoretical properties of the metrics defined.

  12. About Using the Metric System.

    ERIC Educational Resources Information Center

    Illinois State Office of Education, Springfield.

    This booklet contains a brief introduction to the use of the metric system. Topics covered include: (1) what is the metric system; (2) how to think metric; (3) some advantages of the metric system; (4) basics of the metric system; (5) how to measure length, area, volume, mass and temperature the metric way; (6) some simple calculations using…

  13. Effects of toroidicity on resistive tearing modes

    SciTech Connect

    Izzo, R.; Monticello, D.A.; Manickam, J.; Strauss, H.R.; Grimm, R.; McGuire, K.

    1983-03-01

    A reduced set of resistive MHD equations is solved numerically in three dimensions to study the stability of tokamak plasmas. Toroidal effects are included self-consistently to leading and next order in inverse aspect ratio, epsilon. The equations satisfy an energy integral. In addition, the momentum equation yields the Grad-Shafranov equation correct to all orders in epsilon. Low beta plasma are studied using several different q-profiles. In all cases, the linear growth rates are reduced by finite toroidicity. Excellent agreement with resistive PEST is obtianed. In some cases, toroidal effects lead to complete stabilization of the mode. Nonlinear results show smaller saturated island widths for finite aspect ratio compared to the cylindrical limit. If the current channel is wide enough so as to produce steep gradients towards the outside of the plasma, both the finite aspect ratio cases and cylindrical cases disrupt.

  14. Possible effects of iron deposition on the measurement of DTI metrics in deep gray matter nuclei: an in vitro and in vivo study.

    PubMed

    Zhang, Jiuquan; Tao, Ran; Liu, Chen; Wu, Wenjing; Zhang, Yanwei; Cui, Jinguo; Wang, Jian

    2013-09-13

    The aim of this study was to explore the possible effects of iron deposition on the measurement of diffusion tensor imaging (DTI) metrics in deep gray matter nuclei in the normal human brain. Susceptibility-weighted imaging (SWI) and DTI were performed on nine MnCl2 phantoms and 85 healthy adults. The SWI phase value (PV) and DTI metrics including fractional anisotropy (FA), mean diffusivity (MD), radial diffusivity (RD), and axial diffusivity (AD) were measured in phantoms and the frontal white matter (FWM), caudate (CA), putamen (PU), and globus pallidus (GP) of both hemispheres in healthy adults. The FA correlated linearly with PV and MnCl2 concentrations in phantoms. The PV in the PU was positively correlated with age. The FA was negatively correlated with age in the FWM and positively correlated with age in the PU. AD positively correlated with PV in CA, PU, and GP. FA increased with elevated PV in the PU when controlling for the impact of age. The age-related increasing of PV, which predominantly caused by iron deposition, probably influences the measurement of DTI metrics in the PU in the normal human brain and should be considered when diagnosing various neurodegenerative diseases using DTI metrics. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

  15. A neural net-based approach to software metrics

    NASA Technical Reports Server (NTRS)

    Boetticher, G.; Srinivas, Kankanahalli; Eichmann, David A.

    1992-01-01

    Software metrics provide an effective method for characterizing software. Metrics have traditionally been composed through the definition of an equation. This approach is limited by the fact that all the interrelationships among all the parameters be fully understood. This paper explores an alternative, neural network approach to modeling metrics. Experiments performed on two widely accepted metrics, McCabe and Halstead, indicate that the approach is sound, thus serving as the groundwork for further exploration into the analysis and design of software metrics.

  16. Hysteresis effects and diagnostics of the shock formation in low angular momentum axisymmetric accretion in the Kerr metric

    NASA Astrophysics Data System (ADS)

    Das, Tapas K.; Czerny, B.

    2012-04-01

    The secular evolution of the purely general relativistic low angular momentum accretion flow around a spinning black hole is shown to exhibit hysteresis effects. This confirms that a stationary shock is an integral part of such an accretion disc in the Kerr metric. The equations describing the space gradient of the dynamical flow velocity of the accreting matter have been shown to be equivalent to a first order autonomous dynamical systems. Fixed point analysis ensures that such flow must be multi-transonic for certain astrophysically relevant initial boundary conditions. Contrary to the existing consensus in the literature, the critical points and the sonic points are proved not to be isomorphic in general, they can form in a completely different length scales. Physically acceptable global transonic solutions must produce odd number of critical points. Homoclinic orbits for the flow possessing multiple critical points select the critical point with the higher entropy accretion rate, confirming that the entropy accretion rate is the degeneracy removing agent in the system. However, heteroclinic orbits are also observed for some special situation, where both the saddle type critical points of the flow configuration possesses identical entropy accretion rate. Topologies with heteroclinic orbits are thus the only allowed non-removable degenerate solutions for accretion flow with multiple critical points, and are shown to be structurally unstable. Depending on suitable initial boundary conditions, a homoclinic trajectory can be combined with a standard non-homoclinic orbit through an energy preserving Rankine-Hugoniot type of stationary shock, and multi-critical accretion flow then becomes truly multi-transonic. An effective Lyapunov index has been proposed to analytically confirm why certain class of transonic flow cannot accommodate shock solutions even if it produces multiple critical points.

  17. Menopause: highlighting the effects of resistance training.

    PubMed

    Leite, R D; Prestes, J; Pereira, G B; Shiguemoto, G E; Perez, S E A

    2010-11-01

    The increase in lifespan and in the proportion of elderly women has increased the focus on menopause induced physiological alterations. These modifications are associated with the elevated risk of several pathologies such as cardiovascular disease, diabetes, obesity, hypertension, dyslipidemia, non-alcoholic fat liver disease, among others. Because of estrogen levels decline, many tissue and organs (muscular, bone, adipose tissue and liver) are affected. Additionally, body composition suffers important modifications. In this sense, there is a growing body of concern in understanding the physiological mechanisms involved and establishing strategies to prevent and reverse the effects of menopause. The hormone reposition therapy, diet and physical exercise have been recommended. Among the diverse exercise modalities, resistance training is not commonly used as a therapeutic intervention in the treatment of menopause. Thus, the aim of this review was to analyze the physiological alterations on several organs and systems induced by menopause and ovariectomy (experimental model to reproduce menopause), as well as, to study the effects of resistance training in preventing and reverting these modifications. In conclusion, resistance training promotes beneficial effects on several organs and systems, mainly, on muscular, bone and adipose tissue, allowing for a better quality of life in this population.

  18. A Sensor-Independent Gust Hazard Metric

    NASA Technical Reports Server (NTRS)

    Stewart, Eric C.

    2001-01-01

    A procedure for calculating an intuitive hazard metric for gust effects on airplanes is described. The hazard metric is for use by pilots and is intended to replace subjective pilot reports (PIREPs) of the turbulence level. The hazard metric is composed of three numbers: the first describes the average airplane response to the turbulence, the second describes the positive peak airplane response to the gusts, and the third describes the negative peak airplane response to the gusts. The hazard metric is derived from any time history of vertical gust measurements and is thus independent of the sensor making the gust measurements. The metric is demonstrated for one simulated airplane encountering different types of gusts including those derived from flight data recorder measurements of actual accidents. The simulated airplane responses to the gusts compare favorably with the hazard metric.

  19. Independent Metrics for Protein Backbone and Side-Chain Flexibility: Time Scales and Effects of Ligand Binding.

    PubMed

    Fuchs, Julian E; Waldner, Birgit J; Huber, Roland G; von Grafenstein, Susanne; Kramer, Christian; Liedl, Klaus R

    2015-03-10

    Conformational dynamics are central for understanding biomolecular structure and function, since biological macromolecules are inherently flexible at room temperature and in solution. Computational methods are nowadays capable of providing valuable information on the conformational ensembles of biomolecules. However, analysis tools and intuitive metrics that capture dynamic information from in silico generated structural ensembles are limited. In standard work-flows, flexibility in a conformational ensemble is represented through residue-wise root-mean-square fluctuations or B-factors following a global alignment. Consequently, these approaches relying on global alignments discard valuable information on local dynamics. Results inherently depend on global flexibility, residue size, and connectivity. In this study we present a novel approach for capturing positional fluctuations based on multiple local alignments instead of one single global alignment. The method captures local dynamics within a structural ensemble independent of residue type by splitting individual local and global degrees of freedom of protein backbone and side-chains. Dependence on residue type and size in the side-chains is removed via normalization with the B-factors of the isolated residue. As a test case, we demonstrate its application to a molecular dynamics simulation of bovine pancreatic trypsin inhibitor (BPTI) on the millisecond time scale. This allows for illustrating different time scales of backbone and side-chain flexibility. Additionally, we demonstrate the effects of ligand binding on side-chain flexibility of three serine proteases. We expect our new methodology for quantifying local flexibility to be helpful in unraveling local changes in biomolecular dynamics.

  20. Total Quality Management: An Analysis and Evaluation of the Effectiveness of Performance Metrics for ACAT III Programs of Record

    DTIC Science & Technology

    2014-09-01

    management staff calls. This project investigates whether these metrics align with total quality management ( TQM ) best-practice standards. The framework...performance excellence, the lodestar of TQM . The implementation of details and organizational structure is discussed with a final recommendation.

  1. Frequency of Extreme Heat Event as a Surrogate Exposure Metric for Examining the Human Health Effects of Climate Change.

    PubMed

    Romeo Upperman, Crystal; Parker, Jennifer; Jiang, Chengsheng; He, Xin; Murtugudde, Raghuram; Sapkota, Amir

    2015-01-01

    Epidemiological investigation of the impact of climate change on human health, particularly chronic diseases, is hindered by the lack of exposure metrics that can be used as a marker of climate change that are compatible with health data. Here, we present a surrogate exposure metric created using a 30-year baseline (1960-1989) that allows users to quantify long-term changes in exposure to frequency of extreme heat events with near unabridged spatial coverage in a scale that is compatible with national/state health outcome data. We evaluate the exposure metric by decade, seasonality, area of the country, and its ability to capture long-term changes in weather (climate), including natural climate modes. Our findings show that this generic exposure metric is potentially useful to monitor trends in the frequency of extreme heat events across varying regions because it captures long-term changes; is sensitive to the natural climate modes (ENSO events); responds well to spatial variability, and; is amenable to spatial/temporal aggregation, making it useful for epidemiological studies.

  2. Effect of nonsymmetrical flow resistance upon orifice impedance resistance

    NASA Technical Reports Server (NTRS)

    Posey, J. W.; Compton, K. J.

    1974-01-01

    A nonreactive orifice in an infinite baffle is analyzed. The pressure difference delta across the orifice varies sinusoidally with amplitude 1.0 and average value -P. The orifice resistance, delta p is discontinuous at zero velocity and exhibits the constant values R sub + and R sub - for u 0 and u 0, respectively. The resultant velocity has power in all harmonics of the excitation frequency. A quasi-linear resistance is defined and found to be relatively insensitive to the presence or absence of a resonant backing cavity; however, it does vary from 1.33 R sub + to 0.67 R sub + for a resistance ratio R sub +/R sub - between 0.5 and 2.0.

  3. Leading Gainful Employment Metric Reporting

    ERIC Educational Resources Information Center

    Powers, Kristina; MacPherson, Derek

    2016-01-01

    This chapter will address the importance of intercampus involvement in reporting of gainful employment student-level data that will be used in the calculation of gainful employment metrics by the U.S. Department of Education. The authors will discuss why building relationships within the institution is critical for effective gainful employment…

  4. Powerful Metrics: Strategic and Transformative

    ERIC Educational Resources Information Center

    Butterfield, Barbara

    2006-01-01

    To be a valuable partner at the strategic level, human resources can and should contribute to both institutional effectiveness measurement and workforce metrics. In this article, the author examines how to link HR initiatives with key institutional strategies, clarifies essential HR responsibilities for workforce results, explores return on human…

  5. Leading Gainful Employment Metric Reporting

    ERIC Educational Resources Information Center

    Powers, Kristina; MacPherson, Derek

    2016-01-01

    This chapter will address the importance of intercampus involvement in reporting of gainful employment student-level data that will be used in the calculation of gainful employment metrics by the U.S. Department of Education. The authors will discuss why building relationships within the institution is critical for effective gainful employment…

  6. Metrics for Blueprint Reading.

    ERIC Educational Resources Information Center

    Cooper, Gloria S., Ed.; Magisos, Joel H., Ed.

    Designed to meet the job-related metric measurement needs of blueprint reading students, this instructional package is one of eight for the manufacturing occupations cluster, part of a set of 55 packages for metric instruction in different occupations. The package is intended for students who already know the occupational terminology, measurement…

  7. Metrics for Food Distribution.

    ERIC Educational Resources Information Center

    Cooper, Gloria S., Ed.; Magisos, Joel H., Ed.

    Designed to meet the job-related metric measurement needs of students interested in food distribution, this instructional package is one of five for the marketing and distribution cluster, part of a set of 55 packages for metric instruction in different occupations. The package is intended for students who already know the occupational…

  8. Metrics for Transportation.

    ERIC Educational Resources Information Center

    Cooper, Gloria S., Ed.; Magisos, Joel H., Ed.

    Designed to meet the job-related metric measurement needs of students interested in transportation, this instructional package is one of five for the marketing and distribution cluster, part of a set of 55 packages for metric instruction in different occupations. The package is intended for students who already know the occupational terminology,…

  9. Surveillance Metrics Sensitivity Study

    SciTech Connect

    Bierbaum, R; Hamada, M; Robertson, A

    2011-11-01

    In September of 2009, a Tri-Lab team was formed to develop a set of metrics relating to the NNSA nuclear weapon surveillance program. The purpose of the metrics was to develop a more quantitative and/or qualitative metric(s) describing the results of realized or non-realized surveillance activities on our confidence in reporting reliability and assessing the stockpile. As a part of this effort, a statistical sub-team investigated various techniques and developed a complementary set of statistical metrics that could serve as a foundation for characterizing aspects of meeting the surveillance program objectives. The metrics are a combination of tolerance limit calculations and power calculations, intending to answer level-of-confidence type questions with respect to the ability to detect certain undesirable behaviors (catastrophic defects, margin insufficiency defects, and deviations from a model). Note that the metrics are not intended to gauge product performance but instead the adequacy of surveillance. This report gives a short description of four metrics types that were explored and the results of a sensitivity study conducted to investigate their behavior for various inputs. The results of the sensitivity study can be used to set the risk parameters that specify the level of stockpile problem that the surveillance program should be addressing.

  10. Surveillance metrics sensitivity study.

    SciTech Connect

    Hamada, Michael S.; Bierbaum, Rene Lynn; Robertson, Alix A.

    2011-09-01

    In September of 2009, a Tri-Lab team was formed to develop a set of metrics relating to the NNSA nuclear weapon surveillance program. The purpose of the metrics was to develop a more quantitative and/or qualitative metric(s) describing the results of realized or non-realized surveillance activities on our confidence in reporting reliability and assessing the stockpile. As a part of this effort, a statistical sub-team investigated various techniques and developed a complementary set of statistical metrics that could serve as a foundation for characterizing aspects of meeting the surveillance program objectives. The metrics are a combination of tolerance limit calculations and power calculations, intending to answer level-of-confidence type questions with respect to the ability to detect certain undesirable behaviors (catastrophic defects, margin insufficiency defects, and deviations from a model). Note that the metrics are not intended to gauge product performance but instead the adequacy of surveillance. This report gives a short description of four metrics types that were explored and the results of a sensitivity study conducted to investigate their behavior for various inputs. The results of the sensitivity study can be used to set the risk parameters that specify the level of stockpile problem that the surveillance program should be addressing.

  11. Arbitrary Metrics in Psychology

    ERIC Educational Resources Information Center

    Blanton, Hart; Jaccard, James

    2006-01-01

    Many psychological tests have arbitrary metrics but are appropriate for testing psychological theories. Metric arbitrariness is a concern, however, when researchers wish to draw inferences about the true, absolute standing of a group or individual on the latent psychological dimension being measured. The authors illustrate this in the context of 2…

  12. Metric Education Evaluation Package.

    ERIC Educational Resources Information Center

    Kansky, Bob; And Others

    This document was developed out of a need for a complete, carefully designed set of evaluation instruments and procedures that might be applied in metric inservice programs across the nation. Components of this package were prepared in such a way as to permit local adaptation to the evaluation of a broad spectrum of metric education activities.…

  13. Metrics for Cosmetology.

    ERIC Educational Resources Information Center

    Cooper, Gloria S., Ed.; Magisos, Joel H., Ed.

    Designed to meet the job-related metric measurement needs of cosmetology students, this instructional package on cosmetology is part of a set of 55 packages for metric instruction in different occupations. The package is intended for students who already know the occupational terminology, measurement terms, and tools currently in use. Each of the…

  14. Metrics for Aviation Electronics.

    ERIC Educational Resources Information Center

    Cooper, Gloria S., Ed.; Magisos, Joel H., Ed.

    Designed to meet the job-related metric measurement needs of aviation electronics students, this instructional package is one of four for the transportation occupations cluster, part of a set of 55 packages for metric instruction in different occupations. The package is intended for students who already know the occupational terminology,…

  15. Arbitrary Metrics in Psychology

    ERIC Educational Resources Information Center

    Blanton, Hart; Jaccard, James

    2006-01-01

    Many psychological tests have arbitrary metrics but are appropriate for testing psychological theories. Metric arbitrariness is a concern, however, when researchers wish to draw inferences about the true, absolute standing of a group or individual on the latent psychological dimension being measured. The authors illustrate this in the context of 2…

  16. Metrics for Dental Assistants.

    ERIC Educational Resources Information Center

    Cooper, Gloria S., Ed.; Magisos, Joel H., Ed.

    Designed to meet the job-related metric measurement needs of students interested in becoming dental assistants, this instructional package is one of five for the health occupations cluster, part of a set of 55 packages for metric instruction in different occupations. The package is intended for students who already know the occupational…

  17. A Measured Metric Statement.

    ERIC Educational Resources Information Center

    Gaughan, Edward D.; Wisner, Robert J.

    1981-01-01

    A middle-road approach towards adopting the instruction of the metric system is presented. The realities of our cultural, economic, and political processes are taken into account and a 100 percent metric curriculum is viewed as unrealistic and anachronistic. (MP)

  18. Metrics for Fire Service.

    ERIC Educational Resources Information Center

    Cooper, Gloria S., Ed.; Magisos, Joel H., Ed.

    Designed to meet the job-related metric measurement needs of students interested in fire science education, this instructional package is one of two for the public service occupations cluster, part of a set of 55 packages for metric instruction in different occupations. The package is intended for students who already know the occupational…

  19. The Science News Metrics

    NASA Astrophysics Data System (ADS)

    Christian, Carol A.; Davidson, Greg

    2006-01-01

    Scientists, observatories, academic institutions and funding agencies persistently review the usefulness and productivity of investment in scientific research. The Science News Metrics was created over 10 years ago to review NASA's performance in this arena. The metric has been useful for many years as one facet in measuring the scientific discovery productivity of NASA-funded missions. The metric is computed independently of the agency and has been compiled in a consistent manner. Examination of the metric yields year-by-year insight into NASA science successes in a world wide context. The metric has shown that NASA's contribution to worldwide top science news stories has been approximately 5% overall with the Hubble Space Telescope dominating the performance.

  20. Assessment of a prognostic model, PSA metrics and toxicities in metastatic castrate resistant prostate cancer using data from Project Data Sphere (PDS)

    PubMed Central

    Hamilton, Robert J.; Abdallah, Kald; Pintilie, Melania; Joshua, Anthony M.

    2017-01-01

    Background Prognostic models in metastatic castrate resistant prostate cancer (mCRPC) may have clinical utility. Using data from PDS, we aimed to 1) validate a contemporary prognostic model (Templeton et al., 2014) 2) evaluate prognostic impact of concomitant medications and PSA decrease 3) evaluate factors associated with docetaxel toxicity. Methods We accessed data on 2,449 mCRPC patients in PDS. The existing model was validated with a continuous risk score, time-dependent receiver operating characteristic (ROC) curves, and corresponding time-dependent Area under the Curve (tAUC). The prognostic effects of concomitant medications and PSA response were assessed by Cox proportional hazards models. One year tAUC was calculated for multivariable prognostic model optimized to our data. Conditional logistic regression models were used to assess associations with grade 3/4 adverse events (G3/4 AE) at baseline and after cycle 1 of treatment. Results Despite limitations of the PDS data set, the existing model was validated; one year AUC, was 0.68 (95% CI 95% CI, .66 to .71) to 0.78 (95%CI, .74 to .81) depending on the subset of datasets used. A new model was constructed with an AUC of .74 (.72 to .77). Concomitant medications low molecular weight heparin and warfarin were associated with poorer survival, Metformin and Cox2 inhibitors were associated with better outcome. PSA response was associated with survival, the effect of which was greatest early in follow-up. Age was associated with baseline risk of G3/4 AE. The odds of experiencing G3/4 AE later on in treatment were significantly greater for subjects who experienced a G3/4 AE in their first cycle (OR 3.53, 95% CI 2.53–4.91, p < .0001). Conclusion Despite heterogeneous data collection protocols, PDS provides access to large datasets for novel outcomes analysis. In this paper, we demonstrate its utility for validating existing models and novel model generation including the utility of concomitant medications in

  1. Development of local complexity metrics to quantify the effect of anatomical noise on detectability of lung nodules in chest CT imaging

    NASA Astrophysics Data System (ADS)

    Solomon, Justin; Rubin, Geoffrey; Smith, Taylor; Harrawood, Brian; Choudhury, Kingshuk Roy; Samei, Ehsan

    2017-03-01

    The purpose of this study was to develop metrics of local anatomical complexity and compare them with detectability of lung nodules in CT. Data were drawn retrospectively from a published perception experiment in which detectability was assessed in cases enriched with virtual nodules (13 radiologists x 157 total nodules = 2041 responses). A local anatomical complexity metric called the distractor index was developed, defined as the Gaussian weighted proportion (i.e., average) of distracting local voxels (50 voxels in-plane, 5 slices). A distracting voxel was classified by thresholding image data that had been selectively filtered to enhance nodule-like features. The distractor index was measured for each nodule location in the nodule-free images. The local pixel standard deviation (STD) was also measured for each nodule. Other confounding factors of search fraction (proportion of lung voxels to total voxels in the given slice) and peripheral distance (defined as the 3D distance of the nodule from the trachea bifurcation) were measured. A generalized linear mixed-effects statistical model (no interaction terms, probit link function, random reader term) was fit to the data to determine the influence of each metric on detectability. In order of decreasing effect size: distractor index, STD, and search fraction all significantly affected detectability (P < 0.001). Distance to the trachea did not have a significant effect (P < 0.05). These data demonstrate that local lung complexity degrades detection of lung nodules and the distractor index could serve as a good surrogate metric to quantify anatomical complexity.

  2. The effects of resistance strategies on rape.

    PubMed Central

    Zoucha-Jensen, J M; Coyne, A

    1993-01-01

    This investigation sought to clarify which resistance strategies were associated with rape avoidance and at what cost. Data were gathered from initial and supplemental police reports about 150 sexual assault victims, ages 16 and older, who were assaulted between June 1, 1988, and May 31, 1989, in Omaha, Neb. Although this analysis could not determine causality, it did indicate that forceful verbal resistance, physical resistance, and fleeing were all associated with rape avoidance, whereas nonforceful verbal resistance and no resistance were associated with being raped. Further, women who used forceful resistance were no more likely to be injured than women who did not resist. PMID:8238695

  3. Holographic Spherically Symmetric Metrics

    NASA Astrophysics Data System (ADS)

    Petri, Michael

    The holographic principle (HP) conjectures, that the maximum number of degrees of freedom of any realistic physical system is proportional to the system's boundary area. The HP has its roots in the study of black holes. It has recently been applied to cosmological solutions. In this article we apply the HP to spherically symmetric static space-times. We find that any regular spherically symmetric object saturating the HP is subject to tight constraints on the (interior) metric, energy-density, temperature and entropy-density. Whenever gravity can be described by a metric theory, gravity is macroscopically scale invariant and the laws of thermodynamics hold locally and globally, the (interior) metric of a regular holographic object is uniquely determined up to a constant factor and the interior matter-state must follow well defined scaling relations. When the metric theory of gravity is general relativity, the interior matter has an overall string equation of state (EOS) and a unique total energy-density. Thus the holographic metric derived in this article can serve as simple interior 4D realization of Mathur's string fuzzball proposal. Some properties of the holographic metric and its possible experimental verification are discussed. The geodesics of the holographic metric describe an isotropically expanding (or contracting) universe with a nearly homogeneous matter-distribution within the local Hubble volume. Due to the overall string EOS the active gravitational mass-density is zero, resulting in a coasting expansion with Ht = 1, which is compatible with the recent GRB-data.

  4. Pyrethroid resistance in Phytoseiulus macropilis (Acari: Phytoseiidae): cross-resistance, stability and effect of synergists.

    PubMed

    Queiroz, Maria Cristina Vitelli; Sato, Mario Eidi

    2016-01-01

    Phytoseiulus macropilis Banks (Acari: Phytoseiidae) is an effective predator of Tetranychus urticae Koch (Acari: Tetranychidae). The objectives of this research were to study the stability of fenpropathrin resistance and the cross-resistance relationships with different pyrethroids, and also to evaluate the effect of synergists [piperonyl butoxide (PBO), diethyl maleate (DEM) and S,S,S-tributyl phosphorotrithioate (DEF)] on fenpropathrin resistant and susceptible strains of this predaceous mite. The stability of fenpropathrin resistance was studied under laboratory conditions, using P. macropilis populations with initial frequencies of 75 and 50% of resistant mites. The percentages of fenpropathrin resistant mites were evaluated monthly for a period of up to 12 months. A trend toward decreased resistance frequencies was observed only during the first 3-4 months. After this initial decrease, the fenpropathrin resistance was shown to be stable, maintaining constant resistance frequencies (around 30%) until the end of the evaluation period. Toxicity tests carried out using fenpropathrin resistant and susceptible strains of P. macropilis indicated strong positive cross-resistance between fenpropathrin and the pyrethroids bifenthrin and deltamethrin. Bioassays with the synergists DEM, DEF and PBO were also performed. The maximum synergism ratio (SR = LC50 without synergist/LC50 with synergist) detected for the three evaluated synergists (PBO, DEM, DEF) was 5.86 (for DEF), indicating low influence of enzyme detoxification processes in fenpropathrin resistance.

  5. SU-E-I-28: Introduction and Investigation of Effective Diameter Ratios as a New Patient Size Metric for Use in CT

    SciTech Connect

    Lamoureux, R; Sinclair, L; Mench, A; Lipnharski, I; Carranza, C; Bidari, S; Cormack, B; Rill, L; Arreola, M

    2015-06-15

    Purpose: To introduce and investigate effective diameter ratios as a new patient metric for use in computed tomography protocol selection as a supplement to patient-specific size parameter data. Methods: The metrics of outer effective diameter and inner effective diameter were measured for 7 post-mortem subjects scanned with a standardized chest/abdomen/pelvis (CAP) protocol on a 320-slice MDCT scanner. The outer effective diameter was calculated by obtaining the anterior/posterior and lateral dimensions of the imaged anatomy at the middle of the scan range using Effective Diameter= SQRT(AP height*Lat Width). The inner effective diameter was calculated with the same equation using the AP and Lat dimensions of the anatomy excluding the adipose tissue. The ratio of outer to inner effective diameter was calculated for each subject. A relationship to BMI, weight, and CTDI conversion coefficients was investigated. Results: For the largest subject with BMI of 43.85 kg/m2 and weight of 255 lbs the diameter ratio was calculated as 1.33. For the second largest subject with BMI of 33.5 kg/m2 and weight of 192.4 lbs the diameter ratio was measured as 1.43, indicating a larger percentage of adipose tissue in the second largest subject’s anatomical composition. For the smallest subject at BMI of 17.4 kg/m2 and weight of 86 lbs a similar tissue composition was indicated as a subject with BMI of 24.2 kg/m2 and weight of 136 lbs as they had the same diameter ratios of 1.11. Conclusion: The diameter ratio proves to contain information about anatomical composition that the BMI and weight alone do not. The utility of this metric is still being examined but could prove useful for determining MDCT techniques and for giving a more in depth detail of the composition of a patient’s body habitus.

  6. How Robust Are Malaria Parasite Clearance Rates as Indicators of Drug Effectiveness and Resistance?

    PubMed

    Hastings, Ian M; Kay, Katherine; Hodel, Eva Maria

    2015-10-01

    Artemisinin-based combination therapies (ACTs) are currently the first-line drugs for treating uncomplicated falciparum malaria, the most deadly of the human malarias. Malaria parasite clearance rates estimated from patients' blood following ACT treatment have been widely adopted as a measure of drug effectiveness and as surveillance tools for detecting the presence of potential artemisinin resistance. This metric has not been investigated in detail, nor have its properties or potential shortcomings been identified. Herein, the pharmacology of drug treatment, parasite biology, and human immunity are combined to investigate the dynamics of parasite clearance following ACT. This approach parsimoniously recovers the principal clinical features and dynamics of clearance. Human immunity is the primary determinant of clearance rates, unless or until artemisinin killing has fallen to near-ineffective levels. Clearance rates are therefore highly insensitive metrics for surveillance that may lead to overconfidence, as even quite substantial reductions in drug sensitivity may not be detected as lower clearance rates. Equally serious is the use of clearance rates to quantify the impact of ACT regimen changes, as this strategy will plausibly miss even very substantial increases in drug effectiveness. In particular, the malaria community may be missing the opportunity to dramatically increase ACT effectiveness through regimen changes, particularly through a switch to twice-daily regimens and/or increases in artemisinin dosing levels. The malaria community therefore appears overreliant on a single metric of drug effectiveness, the parasite clearance rate, that has significant and serious shortcomings. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

  7. Sustainability Indicators and Metrics

    EPA Science Inventory

    Sustainability is about preserving human existence. Indicators and metrics are absolutely necessary to provide at least a semi-quantitative assessment of progress towards or away from sustainability. Otherwise, it becomes impossible to objectively assess whether progress is bei...

  8. An Arithmetic Metric

    ERIC Educational Resources Information Center

    Dominici, Diego

    2011-01-01

    This work introduces a distance between natural numbers not based on their position on the real line but on their arithmetic properties. We prove some metric properties of this distance and consider a possible extension.

  9. General Motors Goes Metric

    ERIC Educational Resources Information Center

    Webb, Ted

    1976-01-01

    Describes the program to convert to the metric system all of General Motors Corporation products. Steps include establishing policy regarding employee-owned tools, setting up training plans, and making arrangements with suppliers. (MF)

  10. Sustainability Indicators and Metrics

    EPA Science Inventory

    Sustainability is about preserving human existence. Indicators and metrics are absolutely necessary to provide at least a semi-quantitative assessment of progress towards or away from sustainability. Otherwise, it becomes impossible to objectively assess whether progress is bei...

  11. An Arithmetic Metric

    ERIC Educational Resources Information Center

    Dominici, Diego

    2011-01-01

    This work introduces a distance between natural numbers not based on their position on the real line but on their arithmetic properties. We prove some metric properties of this distance and consider a possible extension.

  12. A metric for success

    NASA Astrophysics Data System (ADS)

    Carver, Gary P.

    1994-05-01

    The federal agencies are working with industry to ease adoption of the metric system. The goal is to help U.S. industry compete more successfully in the global marketplace, increase exports, and create new jobs. The strategy is to use federal procurement, financial assistance, and other business-related activities to encourage voluntary conversion. Based upon the positive experiences of firms and industries that have converted, federal agencies have concluded that metric use will yield long-term benefits that are beyond any one-time costs or inconveniences. It may be time for additional steps to move the Nation out of its dual-system comfort zone and continue to progress toward metrication. This report includes 'Metric Highlights in U.S. History'.

  13. Metric Conversion and the School Shop

    ERIC Educational Resources Information Center

    Jackman, Arthur A.

    1976-01-01

    Cost of metric conversion in school shops is examined, and the author categories all the shops in the school and gives useful information on which shops are the easiest to convert, which are most complicated, where resistance is most likely to be met, and where conversion is most urgent. The math department is seen as catalyst. (Editor/HD)

  14. Enterprise Sustainment Metrics

    DTIC Science & Technology

    The Air Force sustainment enterprise does not have metrics that . . . adequately measure key sustainment parameters, according to the 2011 National...Research Council of the National Academies study, Examination of the U.S. Air Force’s Aircraft Sustainment Needs in the Future and Its Strategy to Meet...standardized and do not contribute to the overall assessment of the sustainment enterprise. This paper explores the development of a single metric

  15. Guidelines for metrication at Lawrence Berkeley Laboratory

    SciTech Connect

    Not Available

    1993-07-01

    This document provides a set of guidelines for the metric transition process already under way at Lawrence Berkeley Laboratory. LBL has embarked upon this course in response to Section 5164 of the Trade and Competitiveness Act of 1988, Executive Order 12770 of 1991, and DOE Order 5900.2. The core provision of DOE Order 5900.2 is Section 7b, which states: {open_quotes}Metric usage shall be required except to the extent that such use is impractical, or is likely to cause significant inefficiencies to, or loss of markets by United States firms, or an inability of the Department to fulfill its responsibilities under the laws of the Federal Government and the United States.{close_quotes} LBL`s metrication policy is meant to comply with this requirement by aggressively fostering metrication. The purpose of these guidelines is to optimize the coherence and the cost-effectiveness of the metrication process.

  16. Effectiveness of amiodarone in resistant arrhythmias1

    PubMed Central

    Hollman, Arthur; Holt, Phyllis M

    1980-01-01

    Amiodarone is used in the treatment of previously drug-resistant supraventricular and ventricular arrhythmias. We report our experience with amiodarone in 8 patients. Five patients had paroxysmal atrial flutter, one had paroxysmal atrial fibrillation, one had supraventricular tachycardia, and one ventricular tachycardia. Considerable improvement, both objectively and subjectively, was observed in all patients. Side effects were as follows: all patients had corneal microdeposits, one developed left bundle branch block which resolved on stopping amiodarone, and one reported constipation and abdominal pains. Six patients have been treated for 10–28 months; 3 developed tolerance at 4–14 months after the introduction of amiodarone therapy, but symptoms improved with increased dosage. It is important to watch for the development of tolerance to this drug. PMID:7452643

  17. The effect of vacuum annealing on corrosion resistance of titanium

    SciTech Connect

    Chikanov, V.N.; Peshkov, V.V.; Kireev, L.S.

    1994-09-01

    The effect of annealing on the corrosion resistance of OT4-1 sheet titanium in 25% HCl under various air pressures and self-evacuating conditions has been investigated. From the kinetic corrosion curves it follows that the least corrosion resistance of titanium is observed after vacuum annealing. Even low residual air pressure in a chamber improves corrosion resistance. The corrosion resistance of titanium decreases with vacuum-annealing time.

  18. Robust Transfer Metric Learning for Image Classification.

    PubMed

    Ding, Zhengming; Fu, Yun

    2017-02-01

    Metric learning has attracted increasing attention due to its critical role in image analysis and classification. Conventional metric learning always assumes that the training and test data are sampled from the same or similar distribution. However, to build an effective distance metric, we need abundant supervised knowledge (i.e., side/label information), which is generally inaccessible in practice, because of the expensive labeling cost. In this paper, we develop a robust transfer metric learning (RTML) framework to effectively assist the unlabeled target learning by transferring the knowledge from the well-labeled source domain. Specifically, RTML exploits knowledge transfer to mitigate the domain shift in two directions, i.e., sample space and feature space. In the sample space, domain-wise and class-wise adaption schemes are adopted to bridge the gap of marginal and conditional distribution disparities across two domains. In the feature space, our metric is built in a marginalized denoising fashion and low-rank constraint, which make it more robust to tackle noisy data in reality. Furthermore, we design an explicit rank constraint regularizer to replace the rank minimization NP-hard problem to guide the low-rank metric learning. Experimental results on several standard benchmarks demonstrate the effectiveness of our proposed RTML by comparing it with the state-of-the-art transfer learning and metric learning algorithms.

  19. Marketing metrics for medical practices.

    PubMed

    Zahaluk, David; Baum, Neil

    2012-01-01

    There's a saying by John Wanamaker who pontificated, "Half the money I spend on advertising is wasted; the trouble is, I don't know which half". Today you have opportunities to determine which parts of your marketing efforts are effective and what is wasted. However, you have to measure your marketing results. This article will discuss marketing metrics and how to use them to get the best bang for your marketing buck.

  20. Application of bilateral filtration with weight coefficients for similarity metric calculation in optical flow computation algorithm

    NASA Astrophysics Data System (ADS)

    Panin, S. V.; Titkov, V. V.; Lyubutin, P. S.; Chemezov, V. O.; Eremin, A. V.

    2016-11-01

    Application of weight coefficients of the bilateral filter used to determine weighted similarity metrics of image ranges in optical flow computation algorithm that employs 3-dimension recursive search (3DRS) was investigated. By testing the algorithm applying images taken from the public test database Middlebury benchmark, the effectiveness of this weighted similarity metrics for solving the image processing problem was demonstrated. The necessity of matching the equation parameter values when calculating the weight coefficients aimed at taking into account image texture features was proved for reaching the higher noise resistance under the vector field construction. The adaptation technique which allows excluding manual determination of parameter values was proposed and its efficiency was demonstrated.

  1. Thermoelectric Seebeck effect in oxide-based resistive switching memory.

    PubMed

    Wang, Ming; Bi, Chong; Li, Ling; Long, Shibing; Liu, Qi; Lv, Hangbing; Lu, Nianduan; Sun, Pengxiao; Liu, Ming

    2014-08-20

    Reversible resistive switching induced by an electric field in oxide-based resistive switching memory shows a promising application in future information storage and processing. It is believed that there are some local conductive filaments formed and ruptured in the resistive switching process. However, as a fundamental question, how electron transports in the formed conductive filament is still under debate due to the difficulty to directly characterize its physical and electrical properties. Here we investigate the intrinsic electronic transport mechanism in such conductive filament by measuring thermoelectric Seebeck effects. We show that the small-polaron hopping model can well describe the electronic transport process for all resistance states, although the corresponding temperature-dependent resistance behaviours are contrary. Moreover, at low resistance states, we observe a clear semiconductor-metal transition around 150 K. These results provide insight in understanding resistive switching process and establish a basic framework for modelling resistive switching behaviour.

  2. Thermoelectric Seebeck effect in oxide-based resistive switching memory

    PubMed Central

    Wang, Ming; Bi, Chong; Li, Ling; Long, Shibing; Liu, Qi; Lv, Hangbing; Lu, Nianduan; Sun, Pengxiao; Liu, Ming

    2014-01-01

    Reversible resistive switching induced by an electric field in oxide-based resistive switching memory shows a promising application in future information storage and processing. It is believed that there are some local conductive filaments formed and ruptured in the resistive switching process. However, as a fundamental question, how electron transports in the formed conductive filament is still under debate due to the difficulty to directly characterize its physical and electrical properties. Here we investigate the intrinsic electronic transport mechanism in such conductive filament by measuring thermoelectric Seebeck effects. We show that the small-polaron hopping model can well describe the electronic transport process for all resistance states, although the corresponding temperature-dependent resistance behaviours are contrary. Moreover, at low resistance states, we observe a clear semiconductor–metal transition around 150 K. These results provide insight in understanding resistive switching process and establish a basic framework for modelling resistive switching behaviour. PMID:25141267

  3. Successful Experiences in Teaching Metric.

    ERIC Educational Resources Information Center

    Odom, Jeffrey V., Ed.

    In this publication are presentations on specific experiences in teaching metrics, made at a National Bureau of Standards conference. Ideas of value to teachers and administrators are described in reports on: SI units of measure; principles and practices of teaching metric; metric and the school librarian; teaching metric through television and…

  4. Changing to the Metric System.

    ERIC Educational Resources Information Center

    Chambers, Donald L.; Dowling, Kenneth W.

    This report examines educational aspects of the conversion to the metric system of measurement in the United States. Statements of positions on metrication and basic mathematical skills are given from various groups. Base units, symbols, prefixes, and style of the metric system are outlined. Guidelines for teaching metric concepts are given,…

  5. Using Metrics in Industrial Arts.

    ERIC Educational Resources Information Center

    Bame, E. Allen

    This metric supplement is intended as a guide to aid the industrial arts teacher in incorporating metrics in the classroom. A list of student objectives for measurement skills is followed by an overview of the history of measurement, an argument for change to the metric system in the United States, and a discussion of metric basics (common terms).…

  6. U.S. Metric Conversion: Rough Road Ahead

    ERIC Educational Resources Information Center

    Guillen, Michael A.

    1977-01-01

    A survey of the United States' progress toward metrication indicates that, in spite of early industry and government conversion efforts, there exists significant disorientation, dissension, skepticism, and outright resistance among the influential sectors of government and private industry. (BT)

  7. Effects of cost metric on cost-effectiveness of protected-area network design in urban landscapes.

    PubMed

    Burkhalter, J C; Lockwood, J L; Maslo, B; Fenn, K H; Leu, K

    2016-04-01

    A common goal in conservation planning is to acquire areas that are critical to realizing biodiversity goals in the most cost-effective manner. The way monetary acquisition costs are represented in such planning is an understudied but vital component to realizing cost efficiencies. We sought to design a protected-area network within a forested urban region that would protect 17 birds of conservation concern. We compared the total costs and spatial structure of the optimal protected-area networks produced using three acquisition-cost surrogates (area, agricultural land value, and tax-assessed land value). Using the tax-assessed land values there was a 73% and 78% cost savings relative to networks derived using area or agricultural land value, respectively. This cost reduction was due to the considerable heterogeneity in acquisition costs revealed in tax-assessed land values, especially for small land parcels, and the corresponding ability of the optimization algorithm to identify lower-cost parcels for inclusion that had equal value to our target species. Tax-assessed land values also reflected the strong spatial differences in acquisition costs (US$0.33/m(2)-$55/m(2)) and thus allowed the algorithm to avoid inclusion of high-cost parcels when possible. Our results add to a nascent but growing literature that suggests conservation planners must consider the cost surrogate they use when designing protected-area networks. We suggest that choosing cost surrogates that capture spatial- and size-dependent heterogeneity in acquisition costs may be relevant to establishing protected areas in urbanizing ecosystems. © 2015 Society for Conservation Biology.

  8. Effects of atmospheric moisture on rock resistivity.

    NASA Technical Reports Server (NTRS)

    Alvarez, R.

    1973-01-01

    This study examines the changes in resistivity of rock samples as induced by atmospheric moisture. Experiments were performed on samples of hematitic sandstone, pyrite, and galena. The sandstone underwent a change in resistivity of four orders of magnitude when it was measured in a vacuum of 500 ntorr and in air of 37% relative humidity. Pyrite and galena showed no variations in resistivity when they were measured under the same conditions. These results, plus others obtained elsewhere, indicate that rocks of the resistive type are affected in their electrical properties by atmospheric moisture, whereas rocks of the conductive type are not. The experimental evidence obtained is difficult to reconcile with a model of aqueous electrolytic conduction on the sample surface. It is instead suggested that adsorbed water molecules alter the surface resistivity in a manner similar to that observed in semiconductors and insulators.

  9. Effects of atmospheric moisture on rock resistivity.

    NASA Technical Reports Server (NTRS)

    Alvarez, R.

    1973-01-01

    This study examines the changes in resistivity of rock samples as induced by atmospheric moisture. Experiments were performed on samples of hematitic sandstone, pyrite, and galena. The sandstone underwent a change in resistivity of four orders of magnitude when it was measured in a vacuum of 500 ntorr and in air of 37% relative humidity. Pyrite and galena showed no variations in resistivity when they were measured under the same conditions. These results, plus others obtained elsewhere, indicate that rocks of the resistive type are affected in their electrical properties by atmospheric moisture, whereas rocks of the conductive type are not. The experimental evidence obtained is difficult to reconcile with a model of aqueous electrolytic conduction on the sample surface. It is instead suggested that adsorbed water molecules alter the surface resistivity in a manner similar to that observed in semiconductors and insulators.

  10. Health Metrics for Helminth infections

    PubMed Central

    2014-01-01

    Health metrics based on health-adjusted life years have become standard units for comparing the disease burden and treatment benefits of individual health conditions. The Disability-Adjusted Life Year (DALY) and the Quality-Adjusted Life Year (QALY) are the most frequently used in cost-effect analyses in national and global health policy discussions for allocation of health care resources. While sometimes useful, both the DALY and QALY metrics have limitations in their ability to capture the full health impact of helminth infections and other ‘neglected tropical diseases’ (NTDs). Gaps in current knowledge of disease burden are identified, and interim approaches to disease burden assessment are discussed. PMID:24333545

  11. Characterization of the fetal diaphragmatic magnetomyogram and the effect of breathing movements on cardiac metrics of rate and variability.

    PubMed

    Gustafson, Kathleen M; Allen, John J B; Yeh, Hung-Wen; May, Linda E

    2011-07-01

    Breathing movements are one of the earliest fetal motor behaviors to emerge and are a hallmark of fetal well-being. Fetal respiratory sinus arrhythmia (RSA) has been documented but efforts to quantify the influence of breathing on heart rate (HR) and heart rate variability (HRV) are difficult due to the episodic nature of fetal breathing activity. We used a dedicated fetal biomagnetometer to acquire the magnetocardiogram (MCG) between 36 and 38 weeks gestational age (GA). We identified and characterized a waveform observed in the raw data and independent component decomposition that we attribute to fetal diaphragmatic movements during breathing episodes. RSA and increased high frequency power in a time-frequency analysis of the IBI time-series was observed during fetal breathing periods. Using the diaphragmatic magnetomyogram (dMMG) as a marker, we compared time and frequency domain metrics of heart rate and heart rate variability between breathing and non-breathing epochs. Fetal breathing activity resulted in significantly lower HR, increased high frequency power, greater sympathovagal balance, increased short-term HRV and greater parasympathetic input relative to non-breathing episodes confirming the specificity of fetal breathing movements on parasympathetic cardiac influence. No significant differences between breathing and non-breathing epochs were found in two metrics reflecting total HRV or very low, low and intermediate frequency bands. Using the fetal dMMG as a marker, biomagnetometry can help to elucidate the electrophysiologic mechanisms associated with diaphragmatic motor function and may be used to study the longitudinal development of human fetal cardiac autonomic control and breathing activity.

  12. Characterization of the Fetal Diaphragmatic Magnetomyogram and the Effect of Breathing Movements on Cardiac Metrics of Rate and Variability

    PubMed Central

    Gustafson, Kathleen M.; Allen, John J. B.; Yeh, Hung-wen; May, Linda E.

    2011-01-01

    Breathing movements are one of the earliest fetal motor behaviors to emerge andare ahallmark of fetal well-being. Fetal respiratory sinus arrhythmia (RSA) has been documented but efforts to quantify the influence of breathing on heart rate (HR) and heart rate variability (HRV) are difficult due to the episodic nature of fetal breathing activity. We used a dedicated fetal biomagnetometer to acquire the magnetocardiogram (MCG) between 36-38 weeks gestational age (GA). We identified and characterized a waveform observed in the raw data and independent component decomposition that we attribute to fetal diaphragmatic movements during breathing episodes. RSA and increased high frequency power in a time-frequency analysis of the IBI time-series was observed during fetal breathing periods. Using the diaphragmatic magnetomyogram (dMMG) as a marker, we compared time and frequency domain metrics of heartrate and heart rate variability between breathing and non-breathing epochs. Fetal breathing activity resulted in significantly lower HR, increased high frequency power, greater sympathovagal balance, increased short-term HRV andgreater parasympathetic input relative to non-breathing episodesconfirming the specificity of fetal breathing movements on parasympathetic cardiac influence. No significant differences between breathing and non-breathing epochs were found in two metrics reflecting total HRVor very low, low and intermediate frequency bands. Using the fetal dMMG as a marker, biomagnetometry can help to elucidate the electrophysiologic mechanisms associated with diaphragmatic motor function and may be used to study the longitudinal development of human fetal cardiac autonomic control and breathing activity. PMID:21497027

  13. A two dimensional analysis of sheet resistance and contact resistance effects in solar cells

    NASA Technical Reports Server (NTRS)

    Fang, C. R.; Hauser, J. R.

    1978-01-01

    A computer model is developed to study the two-dimensional nature of the sheet resistance and contact resistance effects in solar cells. A major result is the demonstration that the distributed nature of the semiconductor sheet resistance causes the terminal dark I-V characteristics to exhibit an exp(qV/2kT) type dependence even when the one-dimensional characteristics of the cell exhibit an exp(qV/kT) type voltage dependence. The analytical model which is developed provides an easy method for estimating the sheet resistance of a solar cell from the terminal I-V data.

  14. Effect of Ampicillin, Streptomycin, Penicillin and Tetracycline on Metal Resistant and Non-Resistant Staphylococcus aureus

    PubMed Central

    Chudobova, Dagmar; Dostalova, Simona; Blazkova, Iva; Michalek, Petr; Ruttkay-Nedecky, Branislav; Sklenar, Matej; Nejdl, Lukas; Kudr, Jiri; Gumulec, Jaromir; Tmejova, Katerina; Konecna, Marie; Vaculovicova, Marketa; Hynek, David; Masarik, Michal; Kynicky, Jindrich; Kizek, Rene; Adam, Vojtech

    2014-01-01

    There is an arising and concerning issue in the field of bacterial resistance, which is confirmed by the number of deaths associated with drug-resistant bacterial infections. The aim of this study was to compare the effects of antibiotics on Staphylococcus aureus non-resistant strain and strains resistant to cadmium or lead ions. Metal resistant strains were created by the gradual addition of 2 mM solution of metal ions (cadmium or lead) to the S. aureus culture. An increasing antimicrobial effect of ampicillin, streptomycin, penicillin and tetracycline (0, 10, 25, 50, 75, 150, 225 and 300 µM) on the resistant strains was observed using a method of growth curves. A significant growth inhibition (compared to control) of cadmium resistant cells was observed in the presence of all the four different antibiotics. On the other hand, the addition of streptomycin and ampicillin did not inhibit the growth of lead resistant strain. Other antibiotics were still toxic to the bacterial cells. Significant differences in the morphology of cell walls were indicated by changes in the cell shape. Our data show that the presence of metal ions in the urban environment may contribute to the development of bacterial strain resistance to other substances including antibiotics, which would have an impact on public health. PMID:24651395

  15. Effect of ampicillin, streptomycin, penicillin and tetracycline on metal resistant and non-resistant Staphylococcus aureus.

    PubMed

    Chudobova, Dagmar; Dostalova, Simona; Blazkova, Iva; Michalek, Petr; Ruttkay-Nedecky, Branislav; Sklenar, Matej; Nejdl, Lukas; Kudr, Jiri; Gumulec, Jaromir; Tmejova, Katerina; Konecna, Marie; Vaculovicova, Marketa; Hynek, David; Masarik, Michal; Kynicky, Jindrich; Kizek, Rene; Adam, Vojtech

    2014-03-19

    There is an arising and concerning issue in the field of bacterial resistance, which is confirmed by the number of deaths associated with drug-resistant bacterial infections. The aim of this study was to compare the effects of antibiotics on Staphylococcus aureus non-resistant strain and strains resistant to cadmium or lead ions. Metal resistant strains were created by the gradual addition of 2 mM solution of metal ions (cadmium or lead) to the S. aureus culture. An increasing antimicrobial effect of ampicillin, streptomycin, penicillin and tetracycline (0, 10, 25, 50, 75, 150, 225 and 300 µM) on the resistant strains was observed using a method of growth curves. A significant growth inhibition (compared to control) of cadmium resistant cells was observed in the presence of all the four different antibiotics. On the other hand, the addition of streptomycin and ampicillin did not inhibit the growth of lead resistant strain. Other antibiotics were still toxic to the bacterial cells. Significant differences in the morphology of cell walls were indicated by changes in the cell shape. Our data show that the presence of metal ions in the urban environment may contribute to the development of bacterial strain resistance to other substances including antibiotics, which would have an impact on public health.

  16. Generalized two-dimensional (2D) linear system analysis metrics (GMTF, GDQE) for digital radiography systems including the effect of focal spot, magnification, scatter, and detector characteristics

    PubMed Central

    Kuhls-Gilcrist, Andrew T.; Gupta, Sandesh K.; Bednarek, Daniel R.; Rudin, Stephen

    2010-01-01

    The MTF, NNPS, and DQE are standard linear system metrics used to characterize intrinsic detector performance. To evaluate total system performance for actual clinical conditions, generalized linear system metrics (GMTF, GNNPS and GDQE) that include the effect of the focal spot distribution, scattered radiation, and geometric unsharpness are more meaningful and appropriate. In this study, a two-dimensional (2D) generalized linear system analysis was carried out for a standard flat panel detector (FPD) (194-micron pixel pitch and 600-micron thick CsI) and a newly-developed, high-resolution, micro-angiographic fluoroscope (MAF) (35-micron pixel pitch and 300-micron thick CsI). Realistic clinical parameters and x-ray spectra were used. The 2D detector MTFs were calculated using the new Noise Response method and slanted edge method and 2D focal spot distribution measurements were done using a pin-hole assembly. The scatter fraction, generated for a uniform head equivalent phantom, was measured and the scatter MTF was simulated with a theoretical model. Different magnifications and scatter fractions were used to estimate the 2D GMTF, GNNPS and GDQE for both detectors. Results show spatial non-isotropy for the 2D generalized metrics which provide a quantitative description of the performance of the complete imaging system for both detectors. This generalized analysis demonstrated that the MAF and FPD have similar capabilities at lower spatial frequencies, but that the MAF has superior performance over the FPD at higher frequencies even when considering focal spot blurring and scatter. This 2D generalized performance analysis is a valuable tool to evaluate total system capabilities and to enable optimized design for specific imaging tasks. PMID:21243038

  17. Feasibility of a Cost-Effective, Video Analysis Software–Based Mobility Protocol for Objective Spine Kinematics and Gait Metrics: A Proof of Concept Study

    PubMed Central

    Paul, Justin C.; Petrizzo, Anthony; Rizzo, John-Ross; Bianco, Kristina; Maier, Stephen; Errico, Thomas J.; Lafage, Virginie

    2015-01-01

    The purpose of this study was to investigate the potential of a high-throughput, easily implemented, cost-effective, video analysis software–based mobility protocol to quantify spine kinematics. This prospective cohort study of clinical biomechanics implemented 2-dimensional (2D) image processing at a tertiary-care academic institution. Ten healthy, able-bodied volunteers were recruited for 2D videography of gait and functional motion. The reliability of a 2D video analysis software program for gait and range of motion metrics was evaluated over 2 independent experimental sessions, assessing for inter-trial, inter-session, and inter-rater reliability. Healthy volunteers were evaluated for simple forward and side bending, rotation, treadmill stride length, and more complex seated-to-standing tasks. Based on established intraclass correlation coefficients, results indicated that reliability was considered good to excellent for simple forward and side bending, rotation, stride length, and more complex sit-to-standing tasks. In conclusion, a cost-effective, 2D, video analysis software–based mobility protocol represents a feasible and clinically useful approach for objective spine kinematics and gait metrics. As the complication rate of operative management in the setting of spinal deformity is weighed against functional performance and quality of life measures, an objective analysis tool in combination with an appropriate protocol will aid in clinical assessments and lead to an increased evidence base for management options and decision algorithms. PMID:25543099

  18. Feasibility of a cost-effective, video analysis software-based mobility protocol for objective spine kinematics and gait metrics: a proof of concept study.

    PubMed

    Paul, Justin C; Petrizzo, Anthony; Rizzo, John-Ross; Bianco, Kristina; Maier, Stephen; Errico, Thomas J; Lafage, Virginie

    2015-03-01

    The purpose of this study was to investigate the potential of a high-throughput, easily implemented, cost-effective, video analysis software-based mobility protocol to quantify spine kinematics. This prospective cohort study of clinical biomechanics implemented 2-dimensional (2D) image processing at a tertiary-care academic institution. Ten healthy, able-bodied volunteers were recruited for 2D videography of gait and functional motion. The reliability of a 2D video analysis software program for gait and range of motion metrics was evaluated over 2 independent experimental sessions, assessing for inter-trial, inter-session, and inter-rater reliability. Healthy volunteers were evaluated for simple forward and side bending, rotation, treadmill stride length, and more complex seated-to-standing tasks. Based on established intraclass correlation coefficients, results indicated that reliability was considered good to excellent for simple forward and side bending, rotation, stride length, and more complex sit-to-standing tasks. In conclusion, a cost-effective, 2D, video analysis software-based mobility protocol represents a feasible and clinically useful approach for objective spine kinematics and gait metrics. As the complication rate of operative management in the setting of spinal deformity is weighed against functional performance and quality of life measures, an objective analysis tool in combination with an appropriate protocol will aid in clinical assessments and lead to an increased evidence base for management options and decision algorithms.

  19. Metrics of Scholarly Impact

    ERIC Educational Resources Information Center

    Cacioppo, John T.; Cacioppo, Stephanie

    2012-01-01

    Ruscio and colleagues (Ruscio, Seaman, D'Oriano, Stremlo, & Mahalchik, this issue) provide a thoughtful empirical analysis of 22 different measures of individual scholarly impact. The simplest metric is number of publications, which Simonton (1997) found to be a reasonable predictor of career trajectories. Although the assessment of the scholarly…

  20. Adaptable edge quality metric

    NASA Astrophysics Data System (ADS)

    Strickland, Robin N.; Chang, Dunkai K.

    1990-09-01

    A new quality metric for evaluating edges detected by digital image processing algorithms is presented. The metric is a weighted sum of measures of edge continuity smoothness thinness localization detection and noisiness. Through a training process we can design weights which optimize the metric for different users and applications. We have used the metric to compare the results of ten edge detectors when applied to edges degraded by varying degrees of blur and varying degrees and types of noise. As expected the more optimum Difference-of-Gaussians (DOG) and Haralick methods outperform the simpler gradient detectors. At high signal-to-noise (SNR) ratios Haralick''s method is the best choice although it exhibits a sudden drop in performance at lower SNRs. The DOG filter''s performance degrades almost linearly with SNR and maintains a reasonably high level at lower SNRs. The same relative performances are observed as blur is varied. For most of the detectors tested performance drops with increasing noise correlation. Noise correlated in the same direction as the edge is the most destructive of the noise types tested.

  1. Metrical Phonology and SLA.

    ERIC Educational Resources Information Center

    Tice, Bradley S.

    Metrical phonology, a linguistic process of phonological stress assessment and diagrammatic simplification of sentence and word stress, is discussed as it is found in the English language with the intention that it may be used in second language instruction. Stress is defined by its physical and acoustical correlates, and the principles of…

  2. Metrics and Sports.

    ERIC Educational Resources Information Center

    National Collegiate Athletic Association, Shawnee Mission, KS.

    Designed as a guide to aid the National Collegiate Athletic Association membership and others who must relate measurement of distances, weights, and volumes to athletic activity, this document presents diagrams of performance areas with measurements delineated in both imperial and metric terms. Illustrations are given for baseball, basketball,…

  3. Arbitrary Metrics Redux

    ERIC Educational Resources Information Center

    Blanton, Hart; Jaccard, James

    2006-01-01

    Reducing the arbitrariness of a metric is distinct from the pursuit of validity, rational zero points, data transformations, standardization, and the types of statistical procedures one uses to analyze interval-level versus ordinal-level data. A variety of theoretical, methodological, and statistical tools can assist researchers who wish to make…

  4. Metrics of Scholarly Impact

    ERIC Educational Resources Information Center

    Cacioppo, John T.; Cacioppo, Stephanie

    2012-01-01

    Ruscio and colleagues (Ruscio, Seaman, D'Oriano, Stremlo, & Mahalchik, this issue) provide a thoughtful empirical analysis of 22 different measures of individual scholarly impact. The simplest metric is number of publications, which Simonton (1997) found to be a reasonable predictor of career trajectories. Although the assessment of the scholarly…

  5. Software Quality Metrics

    DTIC Science & Technology

    1991-07-01

    March 1979, pp. 121-128. Gorla, Narasimhaiah, Alan C. Benander, and Barbara A. Benander, "Debugging Effort Estimation Using Software Metrics", IEEE...Society, IEEE Guide for the Use of IEEE Standard Dictionary of Measures to Produce Reliable Software, IEEE Std 982.2-1988, June 1989. Jones, Capers

  6. Effect of Tulathromycin on Colonization Resistance, Antimicrobial Resistance, and Virulence of Human Gut Microbiota in Chemostats

    PubMed Central

    Hao, Haihong; Zhou, Shengxi; Cheng, Guyue; Dai, Menghong; Wang, Xu; Liu, Zhenli; Wang, Yulian; Yuan, Zonghui

    2016-01-01

    To evaluate microbiological safety of tulathromycin on human intestinal bacteria, tulathromycin (0, 0.1, 1, 10, and 100 μg/mL) was added into Chemostats. Before and after drug exposure, we monitored (1) population, SCFA products, antimicrobial resistance, and colonization resistance of gut microbiota, and (2) the antimicrobial resistance genes, transferability, virulent genes, pathogenicity of Enterococus faecalis. Results showed that low level of tulathromycin did not exhibit microbiological hazard on resistance selection and colonization resistance. However, high level of tulathromycin (10 and 100 μg/mL) may disturb colonization resistance of human gut microbiota and select antimicrobial resistant E. faecalis. Most of the selected resistant E. faecalis carried resistant gene of ermB, transferable element of Tn1545 and three virulence genes (esp, cylA, and ace). One of them (E. faecalis 143) was confirmed to have higher horizontal transfer risk and higher pathogenicity. The calculated no observable adverse effect concentration (NOAEC) and microbiological acceptable daily intake (mADI) in our study was 1 μg/mL and 14.66 μg/kg.bw/day, respectively. PMID:27092131

  7. Unraveling the effect of resist composition on EUV optics contamination

    NASA Astrophysics Data System (ADS)

    Pollentier, I.; Neira, I.; Goethals, A.-M.; Gronheid, R.; Tarutani, S.; Tamaoki, H.; Tsubaki, H.; Takahashi, T.

    2011-04-01

    EUV lithography is the most promising new technology for the next node of semiconductor devices. Unfortunately, the high energy photons are likely to generate more contamination than observed with ArF or KrF light which can reduce the transmission of the EUV optics. Resist outgassing is considered to be an important contamination source, however, not enough is known about the way a resist composition influences the contamination growth rate, while this information is crucial to guide the development of EUV resists. To reduce the knowledge gap, FUJIFILM and imec started a joint effort aimed at systematically exploring the contribution of the different resist components and at understanding the effect of chemical modifications of the different components on the contamination tendency of resists. The project focuses on (1) the identification and quantification of the outgassing components from resist by RGA measurements, (2) on the quantification of the resist related contamination rate by witness sample (WS) testing, and (3) on the correlation between these two results knowing the details of the resist chemistry. To explore the effect of the resist composition upon contamination growth, the following approach was followed. The focus was put on chemically amplified resists (CAR), since this chemistry is mostly used in EUV lithography. Both PAG blended as well as PAG bound systems were explored, and the following resist components are individually varied: polymer matrix, blocking groups, PAG type and concentration. In this way the total contamination of a resist can be divided into the separate contributions of the different resist components upon the contamination growth rate, which is a huge step forward in the understanding of optics contamination due to resist.

  8. Decomposition-based transfer distance metric learning for image classification.

    PubMed

    Luo, Yong; Liu, Tongliang; Tao, Dacheng; Xu, Chao

    2014-09-01

    Distance metric learning (DML) is a critical factor for image analysis and pattern recognition. To learn a robust distance metric for a target task, we need abundant side information (i.e., the similarity/dissimilarity pairwise constraints over the labeled data), which is usually unavailable in practice due to the high labeling cost. This paper considers the transfer learning setting by exploiting the large quantity of side information from certain related, but different source tasks to help with target metric learning (with only a little side information). The state-of-the-art metric learning algorithms usually fail in this setting because the data distributions of the source task and target task are often quite different. We address this problem by assuming that the target distance metric lies in the space spanned by the eigenvectors of the source metrics (or other randomly generated bases). The target metric is represented as a combination of the base metrics, which are computed using the decomposed components of the source metrics (or simply a set of random bases); we call the proposed method, decomposition-based transfer DML (DTDML). In particular, DTDML learns a sparse combination of the base metrics to construct the target metric by forcing the target metric to be close to an integration of the source metrics. The main advantage of the proposed method compared with existing transfer metric learning approaches is that we directly learn the base metric coefficients instead of the target metric. To this end, far fewer variables need to be learned. We therefore obtain more reliable solutions given the limited side information and the optimization tends to be faster. Experiments on the popular handwritten image (digit, letter) classification and challenge natural image annotation tasks demonstrate the effectiveness of the proposed method.

  9. Latitudinal variation of the effect of aviation NOx emissions on atmospheric ozone and methane and related climate metrics

    NASA Astrophysics Data System (ADS)

    Köhler, M. O.; Rädel, G.; Shine, K. P.; Rogers, H. L.; Pyle, J. A.

    2013-01-01

    We evaluate the response to regional and latitudinal changes in aircraft NOx emissions using several climate metrics (radiative forcing (RF), Global Warming Potential (GWP), Global Temperature change Potential (GTP)). Global chemistry transport model integrations were performed with sustained perturbations in regional aircraft and aircraft-like NOx emissions. The RF due to the resulting ozone and methane changes is then calculated. We investigate the impact of emission changes for specific geographical regions (approximating to USA, Europe, India and China) and cruise altitude emission changes in discrete latitude bands covering both hemispheres. We find that lower latitude emission changes (per Tg N) cause ozone and methane RFs that are about a factor of 6 larger than those from higher latitude emission changes. The net RF is positive for all experiments. The meridional extent of the RF is larger for low latitude emissions. GWPs for all emission changes are positive, with tropical emissions having the largest values; the sign of the GTP depends on the choice of time horizon.

  10. A filled duration illusion in music: Effects of metrical subdivision on the perception and production of beat tempo.

    PubMed Central

    Repp, Bruno H.; Bruttomesso, Meijin

    2010-01-01

    This study replicates and extends previous findings suggesting that metrical subdivision slows the perceived beat tempo (Repp, 2008). Here, musically trained participants produced the subdivisions themselves and were found to speed up, thus compensating for the perceived slowing. This was shown in a synchronization-continuation paradigm (Experiment 1) and in a reproduction task (Experiment 2a). Participants also judged the tempo of a subdivided sequence as being slower than that of a preceding simple beat sequence (Experiment 2b). Experiment 2 also included nonmusician participants, with similar results. Tempo measurements of famous pianists’ recordings of two variation movements from Beethoven sonatas revealed a strong tendency to play the first variation (subdivided beats) faster than the theme (mostly simple beats). A similar tendency was found in musicians’ laboratory performances of a simple theme and variations, despite instruc-tions to keep the tempo constant (Experiment 3a). When playing melodic sequences in which only one of three beats per measure was subdivided, musicians tended to play these beats faster and to perceive them as longer than adjacent beats, and they played the whole sequence faster than a sequence without any subdivisions (Experiments 3b and 3c). The results amply demonstrate a filled duration illusion in rhythm perception and music performance: Intervals containing events seem longer than empty intervals and thus must be shortened to be perceived as equal in duration. PMID:20689669

  11. Radiation Effects of Commercial Resistive Random Access Memories

    NASA Technical Reports Server (NTRS)

    Chen, Dakai; LaBel, Kenneth A.; Berg, Melanie; Wilcox, Edward; Kim, Hak; Phan, Anthony; Figueiredo, Marco; Buchner, Stephen; Khachatrian, Ani; Roche, Nicolas

    2014-01-01

    We present results for the single-event effect response of commercial production-level resistive random access memories. We found that the resistive memory arrays are immune to heavy ion-induced upsets. However, the devices were susceptible to single-event functional interrupts, due to upsets from the control circuits. The intrinsic radiation tolerant nature of resistive memory makes the technology an attractive consideration for future space applications.

  12. The nature of spacetime in bigravity: Two metrics or none?

    NASA Astrophysics Data System (ADS)

    Akrami, Yashar; Koivisto, Tomi S.; Solomon, Adam R.

    2015-01-01

    The possibility of matter coupling to two metrics at once is considered. This appears natural in the most general ghost-free, bimetric theory of gravity, where it unlocks an additional symmetry with respect to the exchange of the metrics. This double coupling, however, raises the problem of identifying the observables of the theory. It is shown that if the two metrics couple minimally to matter, then there is no physical metric to which all matter would universally couple, and that moreover such an effective metric generically does not exist even for an individual matter species. By studying point particle dynamics, a resolution is suggested in the context of Finsler geometry.

  13. Do metrical accents create illusory phenomenal accents?

    PubMed

    Repp, Bruno H

    2010-07-01

    In music that is perceived as metrically structured, events coinciding with the main beat are called metrically accented. Are these accents purely cognitive, or do they perhaps represent illusory increases in perceived loudness or duration, caused by heightened attention to main beats? In four separate tasks, musicians tried to detect a small actual increase or decrease in the loudness or duration of a single note in melodies comprising 12 notes. Musical notation prescribed a meter (6/8) implying a main beat coinciding with every third note. Effects of metrical accentuation on detection performance were found in all four tasks. However, they reflected primarily an increase in sensitivity to physical changes in main beat positions, likely to be due to enhanced attention. There was no evidence of biases indicating illusory phenomenal accents in those positions. By contrast, and independent of metrical structure, pitch accents due to pitch contour pivots were often mistaken for increases in loudness.

  14. Pronounced effects of additional resistance in Andreev reflection spectroscopy

    NASA Astrophysics Data System (ADS)

    Chen, T. Y.; Huang, S. X.; Chien, C. L.

    2010-06-01

    We present a systematic investigation of the additional resistance (RE) , which is an unavoidable consequence of pseudo-four-probe electrical measurements, on the point-contact Andreev reflection (PCAR) spectrum by both modeling and experiments. Instead of considering the total resistance between the two voltage leads across a point contact as a sum of a contact resistance (RC) and a fixed sample resistance (RS) , it is essential to treat the total resistance as a sum of the Andreev resistance RAR and the additional resistance RE , which are, respectively, the resistances affected and unaffected by the Andreev reflection process. We show a detailed formalism of taking RE into account in modeling and demonstrate that the PCAR spectrum can be drastically affected by the presence of RE . Experimentally, we have found that not only RE cannot be readily measured or even estimated, it is in fact different for each contact, depending on the contact resistance and whether the contact is near the purely ballistic regime or the purely diffusive regime. A self-consistent process is necessary to analyze the entire PCAR spectrum, properly normalize the conductance, determine RE , and other parameters including the spin polarization and the superconducting gap for each contact. We determine RE for various contacts on specimens with different resistivity and resolve the causes of RE . For contacts close to the diffusive regime, there are two sources of RE : a dominant contribution which is linearly proportional to the total resistance and a constant value from the sample resistance. We also address the effects of additional resistance when PCAR is administered in the ballistic limit and in the diffusive limit. With the proper treatment of the additional resistance, we demonstrate that PCAR can quantitatively extract essential information of spin polarization and superconducting gap.

  15. Hybrid metric-Palatini stars

    NASA Astrophysics Data System (ADS)

    Danilǎ, Bogdan; Harko, Tiberiu; Lobo, Francisco S. N.; Mak, M. K.

    2017-02-01

    We consider the internal structure and the physical properties of specific classes of neutron, quark and Bose-Einstein condensate stars in the recently proposed hybrid metric-Palatini gravity theory, which is a combination of the metric and Palatini f (R ) formalisms. It turns out that the theory is very successful in accounting for the observed phenomenology, since it unifies local constraints at the Solar System level and the late-time cosmic acceleration, even if the scalar field is very light. In this paper, we derive the equilibrium equations for a spherically symmetric configuration (mass continuity and Tolman-Oppenheimer-Volkoff) in the framework of the scalar-tensor representation of the hybrid metric-Palatini theory, and we investigate their solutions numerically for different equations of state of neutron and quark matter, by adopting for the scalar field potential a Higgs-type form. It turns out that the scalar-tensor definition of the potential can be represented as an Clairaut differential equation, and provides an explicit form for f (R ) given by f (R )˜R +Λeff, where Λeff is an effective cosmological constant. Furthermore, stellar models, described by the stiff fluid, radiation-like, bag model and the Bose-Einstein condensate equations of state are explicitly constructed in both general relativity and hybrid metric-Palatini gravity, thus allowing an in-depth comparison between the predictions of these two gravitational theories. As a general result it turns out that for all the considered equations of state, hybrid gravity stars are more massive than their general relativistic counterparts. Furthermore, two classes of stellar models corresponding to two particular choices of the functional form of the scalar field (constant value, and logarithmic form, respectively) are also investigated. Interestingly enough, in the case of a constant scalar field the equation of state of the matter takes the form of the bag model equation of state describing

  16. Prediction of Flow and Solute Transport in Fractured Media: Comparison of Metrics to Describe Effects of Rough Surfaces

    NASA Astrophysics Data System (ADS)

    Slottke, D.; Ketcham, R. A.; Sharp, J. M.

    2008-05-01

    Fractures dominate fluid flow and transport of solutes when they are open and connected. The prediction of flow through fractured media has implications for development of water resources, petroleum reservoir exploitation, contamination and remediation assessment, and site evaluation for waste repositories. Assessing the impact of surface roughness on fluid flow and solute transport through fractured media from samples on the order of 100 cm2 assumes the existence of a relationship between fracture morphology and discharge that is scale invariant or at least smoothly transformable. Although some studies assume that the length scale at which surface roughness significantly contributes to the discharge through a fracture falls within the size of a typical hand sample, there is a dearth of empirical data supporting an extension of the relationships found at small scales to larger samples. Furthermore, an appropriate metric to describe a fracture volume accurately must be chosen. We compile data from physical flow tests and numerical modeling of two discrete natural fractures of different scales in rhyolitc tuff. The University of Texas HRXCT facility provided computed tomography representations of the fractures that allow analysis of surface roughness and aperture statistics at 0.25mm grid resolution, which form the basis for transmissivity field inputs to numerical models. We show that although a small (10cm2) representative surface can describe roughness, aperture fields are not so well behaved. We compare physical flow test results, modeled flow, and analytical solutions of the cubic law using various methods of assigning a meaningful aperture to illustrate the challenges of accurate modeling of fracture flow without a priori flow information. While a geometric mean aperture of the entire aperture field closely approximates the hydraulic aperture, an arbitrary profile mean aperture has little utility for predictive purposes.

  17. Neoclassical viscosity effects on resistive magnetohydrodynamic modes in toroidal geometry

    SciTech Connect

    Yang, J.G.; Oh, Y.H.; Choi, D.I. ); Kim, J.Y.; Horton, W. )

    1992-03-01

    The flux-surface-averaged linearized resistive magnetohydrodynamic (MHD) boundary-layer equations including the compressibility, diamagnetic drift, and neoclassical viscosity terms are derived in toroidal geometry. These equations describe the resistive layer dynamics of resistive MHD modes over the collisionality regime between the banana plateau and the Pfirsch--Schlueter. From the resulting equations, the effects of neoclassical viscosity on the stability of the tearing and resistive ballooning modes are investigated numerically. Also, a study is given for the problem of how the neoclassical resistive MHD mode is generated as the collisionality is reduced. It is shown that the neoclassical viscosity terms give a significant destabilizing effect for the tearing and resistive ballooning modes. This destabilization comes mainly from the reduction of the stabilizing effect of the parallel ion sound compression by the ion neoclassical viscosity. In the banana-plateau collisionality limit, where the compressibility is negligible, the dispersion relations of the tearing and resistive ballooning modes reduce to the same form, with the threshold value of the driving force given by {Delta}{sub {ital c}}=0. On the other hand, with the finite neoclassical effect it is found that the neoclassical resistive MHD instability is generated in agreement with previous results. Furthermore, it is shown that this later instability can be generated in a wide range of the collisionality including near the Pfirsch--Schlueter regime as well as the banana-plateau regime, suggesting that this mode is a probable cause of anomalous transport.

  18. Designing Effective Resistance Training Programs: A Practical Example.

    ERIC Educational Resources Information Center

    Hedrick, Allen

    2002-01-01

    Suggests that designing effective resistance training programs is a critical task and important priority for strength and conditioning coaches. Focusing on collegiate soccer, the article describes the step-by-step process of designing resistance training and conditioning programs and emphasizes the need to provide athletes with a scientifically…

  19. Effects of Transgenic Glyphosate-Resistant Crops on Water Quality

    USDA-ARS?s Scientific Manuscript database

    Glyphosate (N-[phosphonomethyl] glycine) is a highly effective, non-selective herbicide. Herbicide-resistant crop (HRC) has been the most successful trait used in transgenic crops throughout the world. Transgenic glyphosate-resistant crops (GRCs) have been commercialized and grown extensively in the...

  20. Metric Measurement and Instructional Television

    ERIC Educational Resources Information Center

    Meiring, Steven P.

    1977-01-01

    The television series "MeasureMetric," an instructional series introducing length, area, volume, mass, and temperature measurement in metric settings, is described. Guidelines are given for using the series as a complete learning unit. (JT)

  1. Quality Metrics in Endoscopy

    PubMed Central

    Gurudu, Suryakanth R.

    2013-01-01

    Endoscopy has evolved in the past 4 decades to become an important tool in the diagnosis and management of many digestive diseases. Greater focus on endoscopic quality has highlighted the need to ensure competency among endoscopists. A joint task force of the American College of Gastroenterology and the American Society for Gastrointestinal Endoscopy has proposed several quality metrics to establish competence and help define areas of continuous quality improvement. These metrics represent quality in endoscopy pertinent to pre-, intra-, and postprocedural periods. Quality in endoscopy is a dynamic and multidimensional process that requires continuous monitoring of several indicators and benchmarking with local and national standards. Institutions and practices should have a process in place for credentialing endoscopists and for the assessment of competence regarding individual endoscopic procedures. PMID:24711767

  2. The Kerr metric

    NASA Astrophysics Data System (ADS)

    Teukolsky, Saul A.

    2015-06-01

    This review describes the events leading up to the discovery of the Kerr metric in 1963 and the enormous impact the discovery has had in the subsequent 50 years. The review discusses the Penrose process, the four laws of black hole mechanics, uniqueness of the solution, and the no-hair theorems. It also includes Kerr perturbation theory and its application to black hole stability and quasi-normal modes. The Kerr metric's importance in the astrophysics of quasars and accreting stellar-mass black hole systems is detailed. A theme of the review is the ‘miraculous’ nature of the solution, both in describing in a simple analytic formula the most general rotating black hole, and in having unexpected mathematical properties that make many calculations tractable. Also included is a pedagogical derivation of the solution suitable for a first course in general relativity.

  3. Peltier-Effect-Induced Correction to Ohmic Resistance

    NASA Astrophysics Data System (ADS)

    Cheremisin, M. V.

    2001-02-01

    The standard ohmic measurements by means of two extra leads contain an additional thermal correction to resistance. The current results in heating(cooling) at first(second) sample contact due to Peltier effect. The contacts temperatures are different. The measured voltage is the sum of the ohmic voltage swing and Peltier effect induced thermopower which is linear on current. As a result, the thermal correction to resistance measured exists at $I\\to 0$. The correction should be in comparison with ohmic resistance. Above some critical frequency dependent on thermal inertial effects the thermal correction disappears.

  4. Performance Metrics for Commercial Buildings

    SciTech Connect

    Fowler, Kimberly M.; Wang, Na; Romero, Rachel L.; Deru, Michael P.

    2010-09-30

    Commercial building owners and operators have requested a standard set of key performance metrics to provide a systematic way to evaluate the performance of their buildings. The performance metrics included in this document provide standard metrics for the energy, water, operations and maintenance, indoor environmental quality, purchasing, waste and recycling and transportation impact of their building. The metrics can be used for comparative performance analysis between existing buildings and industry standards to clarify the impact of sustainably designed and operated buildings.

  5. Metrics for Energy Resilience

    SciTech Connect

    Paul E. Roege; Zachary A. Collier; James Mancillas; John A. McDonagh; Igor Linkov

    2014-09-01

    Energy lies at the backbone of any advanced society and constitutes an essential prerequisite for economic growth, social order and national defense. However there is an Achilles heel to today?s energy and technology relationship; namely a precarious intimacy between energy and the fiscal, social, and technical systems it supports. Recently, widespread and persistent disruptions in energy systems have highlighted the extent of this dependence and the vulnerability of increasingly optimized systems to changing conditions. Resilience is an emerging concept that offers to reconcile considerations of performance under dynamic environments and across multiple time frames by supplementing traditionally static system performance measures to consider behaviors under changing conditions and complex interactions among physical, information and human domains. This paper identifies metrics useful to implement guidance for energy-related planning, design, investment, and operation. Recommendations are presented using a matrix format to provide a structured and comprehensive framework of metrics relevant to a system?s energy resilience. The study synthesizes previously proposed metrics and emergent resilience literature to provide a multi-dimensional model intended for use by leaders and practitioners as they transform our energy posture from one of stasis and reaction to one that is proactive and which fosters sustainable growth.

  6. Effects of diurnal, lighting, and angle-of-incidence variation on anterior segment optical coherence tomography (AS-OCT) angle metrics.

    PubMed

    Akil, Handan; Dastiridou, Anna; Marion, Kenneth; Francis, Brian A; Chopra, Vikas

    2017-03-23

    First reported study to assess the effect of diurnal variation on anterior chamber angle measurements, as well as, to re-test the effects of lighting and angle-of-incidence variation on anterior chamber angle (ACA) measurements acquired by time-domain anterior segment optical coherence tomography (AS-OCT). A total of 30 eyes from 15 healthy, normal subjects underwent anterior chamber imaging using a Visante time-domain AS-OCT according to an IRB-approved protocol. For each eye, the inferior angle was imaged twice in the morning (8 am - 10 am) and then again in the afternoon (3 pm - 5 pm), under light meter-controlled conditions with ambient room lighting 'ON' and lights 'OFF', and at 5° angle of incidence increments. The ACA metrics measured for each eye were: angle opening distance (AOD, measured 500 and 750 μm anterior from scleral spur), the trabecular-iris-space area (TISA, measured 500 and 750 μm anterior from scleral spur), and scleral spur angle. Measurements were performed by masked, certified Reading Center graders using the Visante's Internal Measurement Tool. Differences in measurements between morning and afternoon, lighting variations, and angle of incidence were compared. Mean age of the participants was 31.2 years (range 23-58). Anterior chamber angle metrics did not differ significantly from morning to afternoon imaging, or when the angle of incidence was offset by 5° in either direction away from the inferior angle 6 o'clock position. (p-value 0.13-0.93). Angle metrics at the inferior corneal limbus, 6 o'clock position (IC270), with room lighting 'OFF', showed a significant decrease (p < 0.05) compared to room lighting 'ON'. There does not appear to be significant diurnal variation in AS-OCT parameters in normal individuals, but lighting conditions need to be strictly controlled since variation in lighting led to significant variability in AS-OCT parameters. No changes in ACA parameters were noted by varying the angle

  7. Some References on Metric Information.

    ERIC Educational Resources Information Center

    National Bureau of Standards (DOC), Washington, DC.

    This resource work lists metric information published by the U.S. Government and the American National Standards Institute. Also organizations marketing metric materials for education are given. A short table of conversions is included as is a listing of basic metric facts for everyday living. (LS)

  8. Metrication, American Style. Fastback 41.

    ERIC Educational Resources Information Center

    Izzi, John

    The purpose of this pamphlet is to provide a starting point of information on the metric system for any concerned or interested reader. The material is organized into five brief chapters: Man and Measurement; Learning the Metric System; Progress Report: Education; Recommended Sources; and Metrication, American Style. Appendixes include an…

  9. Say "Yes" to Metric Measure.

    ERIC Educational Resources Information Center

    Monroe, Eula Ewing; Nelson, Marvin N.

    2000-01-01

    Provides a brief history of the metric system. Discusses the infrequent use of the metric measurement system in the United States, why conversion from the customary system to the metric system is difficult, and the need for change. (Contains 14 resources.) (ASK)

  10. Metrication in a global environment

    NASA Technical Reports Server (NTRS)

    Aberg, J.

    1994-01-01

    A brief history about the development of the metric system of measurement is given. The need for the U.S. to implement the 'SI' metric system in the international markets, especially in the aerospace and general trade, is discussed. Development of metric implementation and experiences locally, nationally, and internationally are included.

  11. Metric Education Plan for Virginia.

    ERIC Educational Resources Information Center

    Virginia State Dept. of Education, Richmond. Div. of Secondary Education.

    This comprehensive document is the result of statewide planning for the implementation of metric education in Virginia schools. An introduction discusses the rationale, needs, and continuing objectives for metric education. An organizational structure for metric education in Virginia is outlined. Guidelines for administrative planning are…

  12. Metric Education for Adult Learners.

    ERIC Educational Resources Information Center

    Goetsch, David L.

    1978-01-01

    The metric education program developed at Okaloosa-Walton Junior College, Niceville, Florida, for students and the community in general consists of three components: a metric measurement course; multimedia labor for independent study; and metric signs located throughout the campus. Instructional approaches for adult students are noted. (MF)

  13. Evaluating Algorithm Performance Metrics Tailored for Prognostics

    NASA Technical Reports Server (NTRS)

    Saxena, Abhinav; Celaya, Jose; Saha, Bhaskar; Saha, Sankalita; Goebel, Kai

    2009-01-01

    Prognostics has taken a center stage in Condition Based Maintenance (CBM) where it is desired to estimate Remaining Useful Life (RUL) of the system so that remedial measures may be taken in advance to avoid catastrophic events or unwanted downtimes. Validation of such predictions is an important but difficult proposition and a lack of appropriate evaluation methods renders prognostics meaningless. Evaluation methods currently used in the research community are not standardized and in many cases do not sufficiently assess key performance aspects expected out of a prognostics algorithm. In this paper we introduce several new evaluation metrics tailored for prognostics and show that they can effectively evaluate various algorithms as compared to other conventional metrics. Specifically four algorithms namely; Relevance Vector Machine (RVM), Gaussian Process Regression (GPR), Artificial Neural Network (ANN), and Polynomial Regression (PR) are compared. These algorithms vary in complexity and their ability to manage uncertainty around predicted estimates. Results show that the new metrics rank these algorithms in different manner and depending on the requirements and constraints suitable metrics may be chosen. Beyond these results, these metrics offer ideas about how metrics suitable to prognostics may be designed so that the evaluation procedure can be standardized. 1

  14. Metrics for Offline Evaluation of Prognostic Performance

    NASA Technical Reports Server (NTRS)

    Saxena, Abhinav; Celaya, Jose; Saha, Bhaskar; Saha, Sankalita; Goebel, Kai

    2010-01-01

    Prognostic performance evaluation has gained significant attention in the past few years. Currently, prognostics concepts lack standard definitions and suffer from ambiguous and inconsistent interpretations. This lack of standards is in part due to the varied end-user requirements for different applications, time scales, available information, domain dynamics, etc. to name a few. The research community has used a variety of metrics largely based on convenience and their respective requirements. Very little attention has been focused on establishing a standardized approach to compare different efforts. This paper presents several new evaluation metrics tailored for prognostics that were recently introduced and were shown to effectively evaluate various algorithms as compared to other conventional metrics. Specifically, this paper presents a detailed discussion on how these metrics should be interpreted and used. These metrics have the capability of incorporating probabilistic uncertainty estimates from prognostic algorithms. In addition to quantitative assessment they also offer a comprehensive visual perspective that can be used in designing the prognostic system. Several methods are suggested to customize these metrics for different applications. Guidelines are provided to help choose one method over another based on distribution characteristics. Various issues faced by prognostics and its performance evaluation are discussed followed by a formal notational framework to help standardize subsequent developments.

  15. On Applying the Prognostic Performance Metrics

    NASA Technical Reports Server (NTRS)

    Saxena, Abhinav; Celaya, Jose; Saha, Bhaskar; Saha, Sankalita; Goebel, Kai

    2009-01-01

    Prognostics performance evaluation has gained significant attention in the past few years. As prognostics technology matures and more sophisticated methods for prognostic uncertainty management are developed, a standardized methodology for performance evaluation becomes extremely important to guide improvement efforts in a constructive manner. This paper is in continuation of previous efforts where several new evaluation metrics tailored for prognostics were introduced and were shown to effectively evaluate various algorithms as compared to other conventional metrics. Specifically, this paper presents a detailed discussion on how these metrics should be interpreted and used. Several shortcomings identified, while applying these metrics to a variety of real applications, are also summarized along with discussions that attempt to alleviate these problems. Further, these metrics have been enhanced to include the capability of incorporating probability distribution information from prognostic algorithms as opposed to evaluation based on point estimates only. Several methods have been suggested and guidelines have been provided to help choose one method over another based on probability distribution characteristics. These approaches also offer a convenient and intuitive visualization of algorithm performance with respect to some of these new metrics like prognostic horizon and alpha-lambda performance, and also quantify the corresponding performance while incorporating the uncertainty information.

  16. Effects of Cytochrome P450 Inhibition and Induction on the Phenotyping Metrics of the Basel Cocktail: A Randomized Crossover Study.

    PubMed

    Derungs, Adrian; Donzelli, Massimiliano; Berger, Benjamin; Noppen, Christoph; Krähenbühl, Stephan; Haschke, Manuel

    2016-01-01

    Activity of human cytochrome P450 enzymes (CYPs) shows high inter-and intra-individual variability, which is determined by genetic and non-genetic factors. Using a combination of CYP-specific probe drugs, phenotyping cocktails allow simultaneous assessment of the activity of different CYP isoforms. The objective of this study was to characterize the phenotyping metrics of the Basel cocktail in healthy male subjects with induced and inhibited CYP activity. In a randomized crossover study, the probe drugs for simultaneous phenotyping of CYP1A2 (caffeine), CYP2B6 (efavirenz), CYP2C9 (losartan), 2C19 (omeprazole), CYP2D6 (metoprolol), and CYP3A4 (midazolam) were administered to 16 subjects without pretreatment (baseline), after pretreatment with a combination of CYP inhibitors (ciprofloxacin, ketoconazole, and paroxetine), and after CYP induction with rifampicin. All subjects were genotyped. Pharmacokinetic profiles of the probe drugs and their main metabolites and metabolic ratios 2, 4, 6, and 8 h after probe drug application were determined in plasma and compared with the corresponding area under the plasma concentration-time curve (AUC) ratios. The Basel phenotyping cocktail was well tolerated by all subjects independent of pretreatment. Good correlations of metabolic ratios with AUC ratios of the corresponding probe drugs and their metabolites for all three conditions (baseline, CYP inhibition, and CYP induction) were found at 2 h after probe drug administration for CYP3A4, at 4 h for CYP1A2 and CYP2C19, and at 6 h for CYP2B6 and CYP2D6. While CYP inhibition significantly changed AUC ratios and metabolic ratios at these time points for all six CYP isoforms, CYP induction did not significantly change AUC ratios for CYP2C9. For CYP3A4, total 1'-hydroxymidazolam concentrations after pretreatment of samples with β-glucuronidase were needed to obtain adequate reflection of CYP induction by the metabolic ratio. Inhibition of CYP activity can be detected with the

  17. Implications of Metric Choice for Common Applications of Readmission Metrics

    PubMed Central

    Davies, Sheryl; Saynina, Olga; Schultz, Ellen; McDonald, Kathryn M; Baker, Laurence C

    2013-01-01

    Objective. To quantify the differential impact on hospital performance of three readmission metrics: all-cause readmission (ACR), 3M Potential Preventable Readmission (PPR), and Centers for Medicare and Medicaid 30-day readmission (CMS). Data Sources. 2000–2009 California Office of Statewide Health Planning and Development Patient Discharge Data Nonpublic file. Study Design. We calculated 30-day readmission rates using three metrics, for three disease groups: heart failure (HF), acute myocardial infarction (AMI), and pneumonia. Using each metric, we calculated the absolute change and correlation between performance; the percent of hospitals remaining in extreme deciles and level of agreement; and differences in longitudinal performance. Principal Findings. Average hospital rates for HF patients and the CMS metric were generally higher than for other conditions and metrics. Correlations between the ACR and CMS metrics were highest (r = 0.67–0.84). Rates calculated using the PPR and either ACR or CMS metrics were moderately correlated (r = 0.50–0.67). Between 47 and 75 percent of hospitals in an extreme decile according to one metric remained when using a different metric. Correlations among metrics were modest when measuring hospital longitudinal change. Conclusions. Different approaches to computing readmissions can produce different hospital rankings and impact pay-for-performance. Careful consideration should be placed on readmission metric choice for these applications. PMID:23742056

  18. Implicit Contractive Mappings in Modular Metric and Fuzzy Metric Spaces

    PubMed Central

    Hussain, N.; Salimi, P.

    2014-01-01

    The notion of modular metric spaces being a natural generalization of classical modulars over linear spaces like Lebesgue, Orlicz, Musielak-Orlicz, Lorentz, Orlicz-Lorentz, and Calderon-Lozanovskii spaces was recently introduced. In this paper we investigate the existence of fixed points of generalized α-admissible modular contractive mappings in modular metric spaces. As applications, we derive some new fixed point theorems in partially ordered modular metric spaces, Suzuki type fixed point theorems in modular metric spaces and new fixed point theorems for integral contractions. In last section, we develop an important relation between fuzzy metric and modular metric and deduce certain new fixed point results in triangular fuzzy metric spaces. Moreover, some examples are provided here to illustrate the usability of the obtained results. PMID:25003157

  19. Effects of experimentally-enhanced precipitation and nitrogen on resistance, recovery and resilience of a semi-arid grassland after drought.

    PubMed

    Xu, Zhuwen; Ren, Haiyan; Cai, Jiangping; Wang, Ruzhen; Li, Mai-He; Wan, Shiqiang; Han, Xingguo; Lewis, Bernard J; Jiang, Yong

    2014-12-01

    Resistance, recovery and resilience are three important properties of ecological stability, but they have rarely been studied in semi-arid grasslands under global change. We analyzed data from a field experiment conducted in a native grassland in northern China to explore the effects of experimentally enhanced precipitation and N deposition on both absolute and relative measures of community resistance, recovery and resilience--calculated in terms of community cover--after a natural drought. For both absolute and relative measures, communities with precipitation enhancement showed higher resistance and lower recovery, but no change in resilience compared to communities with ambient precipitation in the semi-arid grassland. The manipulated increase in N deposition had little effect on these community stability metrics except for decreased community resistance. The response patterns of these stability metrics to alterations in precipitation and N are generally consistent at community, functional group and species levels. Contrary to our expectations, structural equation modeling revealed that water-driven community resistance and recovery result mainly from changes in community species asynchrony rather than species diversity in the semi-arid grassland. These findings suggest that changes in precipitation regimes may have significant impacts on the response of water-limited ecosystems to drought stress under global change scenarios.

  20. Metric Measures and the Consumer. Reprint from FDA CONSUMER, Dec. 1975-Jan. 1976.

    ERIC Educational Resources Information Center

    Food and Drug Administration (DHEW), Washington, DC.

    Advantages of the metric system for the consumer are discussed. Basic metric units are described, then methods of comparison shopping when items are marked in metric units are explained. The effect of the change to the metric system on packaging and labelling requirements is discussed. (DT)

  1. Random Kähler metrics

    NASA Astrophysics Data System (ADS)

    Ferrari, Frank; Klevtsov, Semyon; Zelditch, Steve

    2013-04-01

    The purpose of this article is to propose a new method to define and calculate path integrals over metrics on a Kähler manifold. The main idea is to use finite dimensional spaces of Bergman metrics, as an approximation to the full space of Kähler metrics. We use the theory of large deviations to decide when a sequence of probability measures on the spaces of Bergman metrics tends to a limit measure on the space of all Kähler metrics. Several examples are considered.

  2. Effect of prolonged hypokinesia on resistance of resistive vessels in rats

    NASA Technical Reports Server (NTRS)

    Saltykova, V. A.

    1982-01-01

    Under the effect of prolonged hypokinesia, the perfusion pressure in resistive vessels, measured under conditions of deep anesthesia and complete denervation, increased by approximately the same degree as arterial pressure in non-anesthetized animals. The increase in arterial, perfusion pressure and the resistance of resistive vessels in animals subjected to prolonged hypokinesia was accompanied by an increase in adrenoreactivity. During prolonged hypokinesia, partial obliteration of the vascular bed of the skeletal muscles plays a significant role in the observed increase in resistance of vessels of the extremities. The increase in adrenoreactivity of the vessels during hypokinesia may be realized as a partial case of an increase in the adrenoreactivity of structures whose innervation is disturbed.

  3. Optical metrics and projective equivalence

    SciTech Connect

    Casey, Stephen; Dunajski, Maciej; Gibbons, Gary; Warnick, Claude

    2011-04-15

    Trajectories of light rays in a static spacetime are described by unparametrized geodesics of the Riemannian optical metric associated with the Lorentzian spacetime metric. We investigate the uniqueness of this structure and demonstrate that two different observers, moving relative to one another, who both see the Universe as static may determine the geometry of the light rays differently. More specifically, we classify Lorentzian metrics admitting more than one hyper-surface orthogonal timelike Killing vector and analyze the projective equivalence of the resulting optical metrics. These metrics are shown to be projectively equivalent up to diffeomorphism if the static Killing vectors generate a group SL(2,R), but not projectively equivalent in general. We also consider the cosmological C metrics in Einstein-Maxwell theory and demonstrate that optical metrics corresponding to different values of the cosmological constant are projectively equivalent.

  4. Retrospective head motion correction approaches for diffusion tensor imaging: Effects of preprocessing choices on biases and reproducibility of scalar diffusion metrics.

    PubMed

    Kreilkamp, Barbara A K; Zacà, Domenico; Papinutto, Nico; Jovicich, Jorge

    2016-01-01

    To evaluate how retrospective head motion correction strategies affect the estimation of scalar metrics commonly used in clinical diffusion tensor imaging (DTI) studies along with their across-session reproducibility errors. Fractional anisotropy (FA), mean diffusivity (MD), radial diffusivity (RD), axial diffusivity (AD) and their respective across-session reproducibility errors were measured on a 4T test-retest dataset of healthy participants using five processing pipelines. These differed in: 1) the number of b0 volumes used for motion correction reference (one or five); 2) the estimations of the gradient matrix rotation (based on 6 or 12 degrees of freedom derived from coregistration); and 3) the software packages used (FSL or DTIPrep). Biases and reproducibility were evaluated in three regions of interest (ROIs) (bilateral arcuate fasciculi, cingula, and the corpus callosum) and also at the full brain level with tract based skeleton images. Preprocessing choices affected DTI measures and their reproducibility. The DTIPrep pipeline exhibited higher DTI metrics: FA/MD and AD (P < 0.05) relative to FSL pipelines both at the ROI and full brain level, and lower RD estimates (P < 0.05) at the ROI level. Within FSL pipelines no such effects were found (P-values ranging between 0.25 and 0.97). The DTIPrep pipeline showed the highest number of white matter skeleton voxels, with significantly higher reproducibility (P < 0.001) relative to the other pipelines (tested on P < 0.01 uncorrected maps). The use of an iteratively averaged b0 image as motion correction reference (as performed by DTIPrep) affects both scalar values and improves test-retest reliability relative to the other tested pipelines. These considerations are potentially relevant for data analysis in longitudinal DTI studies. © 2015 Wiley Periodicals, Inc.

  5. [Effect of Three Typical Disinfection Byproducts on Bacterial Antibiotic Resistance].

    PubMed

    Lü, Lu; Zhang, Meng-lu; Wang, Chun-ming; Lin, Hui-rong; Yu, Xin

    2015-07-01

    The effect of typical disinfection byproducts (DBPs) on bacterial antibiotic resistance was investigated in this study. chlorodibromomethane (CDBM), iodoacetic acid (IAA) and chloral hydrate (CH) were selected, which belong to trihalomethanes (THMs), haloacetic acids (HAAs) and aldehydes, respectively. After exposure to the selected DBPs, the resistance change of the tested strains to antibiotics was determined. As a result, all of the three DBPs induced Pseudomonas aeruginosa PAO1 to gain increased resistance to the five antibiotics tested, and the DBPs ranked as IAA > CH > CDBM according to their enhancement effects. Multidrug resistance could also be enhanced by treatment with IAA. The same result was observed in Escherichia coli K12, suggesting that the effect of DBPs on antibiotic resistance was a common phenomenon. The mechanism was probably that DBPs stimulated oxidative stress, which induced mutagenesis. And the antibiotic resistance mutation frequency could be increased along with mutagenesis. This study revealed that the acquisition of bacterial antibiotic resistance might be related to DBPs in drinking water systems. Besides the genotoxicological risks, the epidemiological risks of DBPs should not be overlooked.

  6. Comparing Resource Adequacy Metrics

    SciTech Connect

    Ibanez, Eduardo; Milligan, Michael

    2014-11-13

    As the penetration of variable generation (wind and solar) increases around the world, there is an accompanying growing interest and importance in accurately assessing the contribution that these resources can make toward planning reserve. This contribution, also known as the capacity credit or capacity value of the resource, is best quantified by using a probabilistic measure of overall resource adequacy. In recognizing the variable nature of these renewable resources, there has been interest in exploring the use of reliability metrics other than loss of load expectation. In this paper, we undertake some comparisons using data from the Western Electricity Coordinating Council in the western United States.

  7. SI (Metric) handbook

    NASA Technical Reports Server (NTRS)

    Artusa, Elisa A.

    1994-01-01

    This guide provides information for an understanding of SI units, symbols, and prefixes; style and usage in documentation in both the US and in the international business community; conversion techniques; limits, fits, and tolerance data; and drawing and technical writing guidelines. Also provided is information of SI usage for specialized applications like data processing and computer programming, science, engineering, and construction. Related information in the appendixes include legislative documents, historical and biographical data, a list of metric documentation, rules for determining significant digits and rounding, conversion factors, shorthand notation, and a unit index.

  8. Degenerate metric phase boundaries

    NASA Astrophysics Data System (ADS)

    Bengtsson, I.; Jacobson, T.

    1997-11-01

    The structure of boundaries between degenerate and non-degenerate solutions of Ashtekar's canonical reformulation of Einstein's equations is studied. Several examples are given of such `phase boundaries' in which the metric is degenerate on one side of a null hypersurface and non-degenerate on the other side. These include portions of flat space, Schwarzschild and plane-wave solutions joined to degenerate regions. In the last case, the wave collides with a planar phase boundary and continues on with the same curvature but degenerate triad, while the phase boundary continues in the opposite direction. We conjecture that degenerate phase boundaries are always null.

  9. Distance Metric Tracking

    DTIC Science & Technology

    2016-03-02

    520, 2004. 16 [12] E.C. Hall and R.M. Willett. Online convex optimization in dynamic environ- ments. Selected Topics in Signal Processing, IEEE Journal...Conference on Machine Learning, pages 1160–1167. ACM, 2008. [25] Eric P Xing, Michael I Jordan, Stuart Russell, and Andrew Y Ng. Distance metric...whereBψ is any Bregman divergence and ηt is the learning rate parameter. From ( Hall & Willett, 2015) we have: Theorem 1. G` = max θ∈Θ,`∈L ‖∇f(θ)‖ φmax = 1

  10. Metrics for Multiagent Systems

    NASA Astrophysics Data System (ADS)

    Lass, Robert N.; Sultanik, Evan A.; Regli, William C.

    A Multiagent System (MAS) is a software paradigm for building large scale intelligent distributed systems. Increasingly these systems are being deployed on handheld computing devices that rely on non-traditional communications mediums such as mobile ad hoc networks and satellite links. These systems present new challenges for computer scientists in describing system performance and analyzing competing systems. This chapter surveys existing metrics that can be used to describe MASs and related components. A framework for analyzing MASs is provided and an example of how this framework might be employed is given for the domain of distributed constraint reasoning.

  11. SI (Metric) handbook

    NASA Astrophysics Data System (ADS)

    Artusa, Elisa A.

    1994-03-01

    This guide provides information for an understanding of SI units, symbols, and prefixes; style and usage in documentation in both the US and in the international business community; conversion techniques; limits, fits, and tolerance data; and drawing and technical writing guidelines. Also provided is information of SI usage for specialized applications like data processing and computer programming, science, engineering, and construction. Related information in the appendixes include legislative documents, historical and biographical data, a list of metric documentation, rules for determining significant digits and rounding, conversion factors, shorthand notation, and a unit index.

  12. Validating Software Metrics

    DTIC Science & Technology

    1990-09-30

    validation test: Spearman Rank Correlation and Wald - Wolfowitz Runs Test (test for randomness) (5,8]. For example, if a complexity metric is claimed to be... error count (E). Validity Criteria Select values of V, B, A, and P. The values of V, B, A, and P, used in the example are .7, .7, 20%, and 80...Procedures with no errors Average rank of first group = 85.2419 based on 31 values . Average rank of second group = 45.5 based on 81 values . Large sample test

  13. Sustainable chemistry metrics.

    PubMed

    Calvo-Flores, Francisco García

    2009-01-01

    Green chemistry has developed mathematical parameters to describe the sustainability of chemical reactions and processes, in order to quantify their environmental impact. These parameters are related to mass and energy magnitudes, and enable analyses and numerical diagnoses of chemical reactions. The environmental impact factor (E factor), atom economy, and reaction mass efficiency have been the most influential metrics, and they are interconnected by mathematical equations. The ecodesign concept must also be considered for complex industrial syntheses, as a part of the sustainability of manufacturing processes. The aim of this Concept article is to identify the main parameters for evaluating undesirable environmental consequences.

  14. Elastic Resistance Effectiveness on Increasing Strength of Shoulders and Hips.

    PubMed

    Picha, Kelsey J; Almaddah, Muataz R; Barker, Jordan; Ciochetty, Tavis; Black, W Scott; Uhl, Tim L

    2017-09-12

    Elastic resistance is a common training method used to gain strength. Currently, progression with elastic resistance is based on the perceived exertion of the exercise or completion of targeted repetitions; exact resistance is typically unknown. This study's objective is to determine if knowledge of load during elastic resistance exercise will increase strength gains during exercises. Participants were randomized into two strength training groups, elastic resistance only and elastic resistance using a load cell (LC) that displays force during exercise. The LC group used a Smart Handle (Patterson Medical Supply, Chicago, IL) to complete all exercises. Each participant completed the same exercises three times weekly for 8 weeks. The LC group was provided with a set load for exercises whereas the elastic resistance only group was not. Participant's strength was tested at baseline and program completion, measuring isometric strength for shoulder abduction (SAb), shoulder external rotation (SER), hip abduction (HAb), and hip extension (HEx). Independent t-tests were used to compare the normalized torques between groups. No significant differences were found between groups. Shoulder strength gains did not differ between groups (SAb p>0.05; SER p>0.05). Hip strength gains did not differ between groups (HAb p>0.05; HEx p>0.05). Both groups increased strength due to individual supervision, constantly evaluating degree of difficulty associated with exercise and providing feedback while using elastic resistance. Using a LC is as effective as supervised training and could provide value in a clinic setting when patients are working unsupervised.

  15. Effect of heat leaks in platinum resistance thermometry.

    PubMed

    Goldratt, E; Yeshurun, Y; Greenfield, A J

    1980-03-01

    The effect of heat leaks in platinum resistance thermometry is analyzed. An experimental method is proposed for estimating the magnitude of this effect. Results are reported for the measurement of the temperature of a hot, solid body under different heat-leak configurations. Design criteria for thermometers are presented which minimize the effect of such heat leaks.

  16. Effect of heat leaks in platinum resistance thermometry

    NASA Astrophysics Data System (ADS)

    Goldratt, E.; Yeshurun, Y.; Greenfield, A. J.

    1980-03-01

    The effect of heat leaks in platinum resistance thermometry is analyzed. An experimental method is proposed for estimating the magnitude of this effect. Results are reported for the measurement of the temperature of a hot, solid body under different heat-leak configurations. Design criteria for thermometers are presented which minimize the effect of such heat leaks.

  17. Early Warning Look Ahead Metrics: The Percent Milestone Backlog Metric

    NASA Technical Reports Server (NTRS)

    Shinn, Stephen A.; Anderson, Timothy P.

    2017-01-01

    All complex development projects experience delays and corresponding backlogs of their project control milestones during their acquisition lifecycles. NASA Goddard Space Flight Center (GSFC) Flight Projects Directorate (FPD) teamed with The Aerospace Corporation (Aerospace) to develop a collection of Early Warning Look Ahead metrics that would provide GSFC leadership with some independent indication of the programmatic health of GSFC flight projects. As part of the collection of Early Warning Look Ahead metrics, the Percent Milestone Backlog metric is particularly revealing, and has utility as a stand-alone execution performance monitoring tool. This paper describes the purpose, development methodology, and utility of the Percent Milestone Backlog metric. The other four Early Warning Look Ahead metrics are also briefly discussed. Finally, an example of the use of the Percent Milestone Backlog metric in providing actionable insight is described, along with examples of its potential use in other commodities.

  18. Exploring Metric Symmetry

    SciTech Connect

    Zwart, P.H.; Grosse-Kunstleve, R.W.; Adams, P.D.

    2006-07-31

    Relatively minor perturbations to a crystal structure can in some cases result in apparently large changes in symmetry. Changes in space group or even lattice can be induced by heavy metal or halide soaking (Dauter et al, 2001), flash freezing (Skrzypczak-Jankun et al, 1996), and Se-Met substitution (Poulsen et al, 2001). Relations between various space groups and lattices can provide insight in the underlying structural causes for the symmetry or lattice transformations. Furthermore, these relations can be useful in understanding twinning and how to efficiently solve two different but related crystal structures. Although (pseudo) symmetric properties of a certain combination of unit cell parameters and a space group are immediately obvious (such as a pseudo four-fold axis if a is approximately equal to b in an orthorhombic space group), other relations (e.g. Lehtio, et al, 2005) that are less obvious might be crucial to the understanding and detection of certain idiosyncrasies of experimental data. We have developed a set of tools that allows straightforward exploration of possible metric symmetry relations given unit cell parameters and a space group. The new iotbx.explore{_}metric{_}symmetry command produces an overview of the various relations between several possible point groups for a given lattice. Methods for finding relations between a pair of unit cells are also available. The tools described in this newsletter are part of the CCTBX libraries, which are included in the latest (versions July 2006 and up) PHENIX and CCI Apps distributions.

  19. Lead-resistance effects in a constant voltage anemometer

    NASA Astrophysics Data System (ADS)

    Comte-Bellot, Geneviève; Weiss, Julien; Béra, Jean-Christophe

    2004-06-01

    Two effects of the lead resistances connecting the hot wire to a constant voltage anemometer (CVA) were analyzed and tested: one concerns the change in the sensitivity coefficient relating the anemometer output to velocity or temperature fluctuations, and the other the time constant of the hot wire determined by an in situ square-wave test technique. Small perturbations were assumed in both cases. The CVA output sensitivity was found to be reduced and the time constant increased with the lead resistance. Explicit formulas which involve the lead resistance, the cold wire resistance, and the wire overheat, as well as some characteristics of the CVA circuit, were established to take into account these effects. In the ranges tested, each effect can individually introduce as much as 10% error. Product of the two governs the overall response for the CVA. However, because the two effects change in opposite directions, interestingly, variation in the net response from their product is minimized. This feature may be very useful for many engineering applications of the CVA. Results of experiments conducted with the CVA in a subsonic jet are presented. They confirm the analysis and also establish that accurate measurements can be performed even with a large ratio of lead resistance to hot-wire resistance by applying the correction formulas developed with the analysis. Results from earlier experiments in a supersonic boundary layer also are presented.

  20. Effect of mechanical surface and heat treatments on erosion resistance

    NASA Technical Reports Server (NTRS)

    Salik, J.; Buckley, D. H.

    1980-01-01

    The effects of mechanical surface treatments as well as heat treatments on the erosion resistance of 6061 aluminum alloy and 1045 steel were studied. Mechanical surface treatments were found to have little or no effect on the erosion resistance. This is due to the formation by particle impact of a work hardened surface layer regardless of the initial surface condition. The erosion resistance of Al single crystals is found to be independent of orientation. This is due to destruction of the surface microstructure and formation of a polycrystalline surface layer by the impact of erodant particles as observed by X-ray diffraction. While upon solution treatment of annealed 6061 aluminum the increase in hardness is accompanied by an increase in erosion resistance, precipitation treatment which causes a further increase in hardness results in slightly lower erosion resistance. Using two types of erodant particles, glass beads and crushed glass, the erosion rate is found to be strongly dependent on erodant particle shape, being an order of magnitude higher for erosion with crushed glass as compared to glass beads. While for erosion with glass beads heat treatment of 1045 steel had a profound effect on its erosion resistance, little or no such effect was observed for erosion with crushed glass.

  1. Effect of curative parathyroidectomy on insulin resistance

    PubMed Central

    Putnam, Rachel; Dhibar, Deba Prasad; Varshney, Shweta; Behera, Arunanshu; Mittal, B. R.; Bhansali, Anil; Rao, Sudhaker D.; Bhadada, Sanjay Kumar

    2016-01-01

    Background: Primary hyperparathyroidism (PHPT) is characterized by inappropriately elevated serum parathyroid hormone (PTH) level despite elevated serum calcium. Insulin resistant is the basic pathophysiology, behind the higher prevalence of diabetes mellitus in patients with PHPT. However, the improvement in insulin resistance (IR) after curative parathyroidectomy (CPTX) has not been established yet, as the study results are conflicting. Materials and Methods: In this prospective interventional study, ten patients with mild PHPT (Group 1) and another ten patients with moderate to severe PHPT (Group 2) were undergone CPTX. The IR was assessed by homeostasis model assessment-IR (HOMA-IR), quantitative insulin sensitivity check index (QUICKI), fasting plasma glucose (FPG), and fasting serum insulin (FSI), before and 3 months after CPTX. Results: There was no significant change of FPG and FSI, before and after CPTX in Group 1 (P = 0.179 and P = 0.104) and Group 2 (P = 0.376 and P = 0.488). Before surgery, HOMA-IR was higher, and QUICKI was significantly lower, in both Group 1 (P = 0.058 and P = 0.009) and Group 2 (P = 0.023 and P = 0.005) as compared to published normal reference mean, with no significant difference between the groups. Three months after surgery HOMA-IR increased further and QUICKI remained unchanged as compared to baseline, in both Group 1 (P = 0.072 and 0.082) and Group 2 (P = 0.54 and 0.56), but statistically insignificant. Conclusion: IR remained unchanged after CPTX in mild as well as moderate to severe PHPT. Asymptomatic PHPT with abnormal IR should not be used as criteria for parathyroidectomy. PMID:27867880

  2. Effect of the eccentricity of normal resistivity borehole tools on the current field and resistivity measurement

    NASA Astrophysics Data System (ADS)

    Galsa, Attila; Herein, Mátyás; Drahos, Dezső; Herein, András

    2016-11-01

    Three-dimensional finite element numerical model calculations have been carried out to investigate the quantitative effect of the eccentric position of a normal resistivity borehole probe used in practice. Detailed calculations were done between the point-wise analytical solution and numerical solution to verify the results obtained from the finite element method for a normal probe with finite-length cylindrical electrodes. In the borehole the pattern of the current flowing out from current electrode A is efficiently influenced by the eccentricity. For high-resistivity rock the current density is decreased, while for low-resistivity rock it is increased toward the wall side. On the other hand, the eccentricity does not affect considerably the apparent resistivity calculated from electrode potentials. In most geological situations the deviation is less than 2%. However, in infrequent cases when the true resistivity of the rock is extremely low and/or the distance between the potential and current electrodes is very small the effect of the eccentricity can exceed even 10%.

  3. Short Lived Climate Pollutants cause a Long Lived Effect on Sea-level Rise: Analyzing climate metrics for sea-level rise

    NASA Astrophysics Data System (ADS)

    Sterner, E.; Johansson, D. J.

    2013-12-01

    Climate change depends on the increase of several different atmospheric pollutants. While long term global warming will be determined mainly by carbon dioxide, warming in the next few decades will depend to a large extent on short lived climate pollutants (SLCP). Reducing emissions of SLCPs could contribute to lower the global mean surface temperature by 0.5 °C already by 2050 (Shindell et al. 2012). Furthermore, the warming effect of one of the most potent SLCPs, black carbon (BC), may have been underestimated in the past. Bond et al. (2013) presents a new best estimate of the total BC radiative forcing (RF) of 1.1 W/m2 (90 % uncertainty bounds of 0.17 to 2.1 W/m2) since the beginning of the industrial era. BC is however never emitted alone and cooling aerosols from the same sources offset a majority of this RF. In the wake of calls for mitigation of SLCPs it is important to study other aspects of the climate effect of SLCPs. One key impact of climate change is sea-level rise (SLR). In a recent study, the effect of SLCP mitigation scenarios on SLR is examined. Hu et al (2013) find a substantial effect on SLR from mitigating SLCPs sharply, reducing SLR by 22-42% by 2100. We choose a different approach focusing on emission pulses and analyse a metric based on sea level rise so as to further enlighten the SLR consequences of SLCPs. We want in particular to understand the time dynamics of SLR impacts caused by SLCPs compared to other greenhouse gases. The most commonly used physical based metrics are GWP and GTP. We propose and evaluate an additional metric: The global sea-level rise potential (GSP). The GSP is defined as the sea level rise after a time horizon caused by an emissions pulse of a forcer to the sea level rise after a time horizon caused by an emissions pulse of a CO2. GSP is evaluated and compared to GWP and GTP using a set of climate forcers chosen to cover the whole scale of atmospheric perturbation life times (BC, CH4, N2O, CO2 and SF6). The study

  4. Predicting the acute behavioral effects in rats inhaling toluene (or up to 24 hrs: Inhaled vs. internal dose metrics.

    EPA Science Inventory

    The acute toxicity oftoluene, a model volatile organic compound (VOC), depends on the concentration (C) and duration (t) ofexposure, and guidelines for acute exposures have traditionally used ext relationships to extrapolate protective and/or effective concentrations across durat...

  5. Predicting the acute behavioral effects in rats inhaling toluene (or up to 24 hrs: Inhaled vs. internal dose metrics.

    EPA Science Inventory

    The acute toxicity oftoluene, a model volatile organic compound (VOC), depends on the concentration (C) and duration (t) ofexposure, and guidelines for acute exposures have traditionally used ext relationships to extrapolate protective and/or effective concentrations across durat...

  6. Effect Sizes for Growth-Modeling Analysis for Controlled Clinical Trials in the Same Metric as for Classical Analysis

    PubMed Central

    Feingold, Alan

    2009-01-01

    The use of growth-modeling analysis (GMA)--including Hierarchical Linear Models, Latent Growth Models, and General Estimating Equations--to evaluate interventions in psychology, psychiatry, and prevention science has grown rapidly over the last decade. However, an effect size associated with the difference between the trajectories of the intervention and control groups that captures the treatment effect is rarely reported. This article first reviews two classes of formulas for effect sizes associated with classical repeated-measures designs that use the standard deviation of either change scores or raw scores for the denominator. It then broadens the scope to subsume GMA, and demonstrates that the independent groups, within-subjects, pretest-posttest control-group, and GMA designs all estimate the same effect size when the standard deviation of raw scores is uniformly used. Finally, it is shown that the correct effect size for treatment efficacy in GMA--the difference between the estimated means of the two groups at end of study (determined from the coefficient for the slope difference and length of study) divided by the baseline standard deviation--is not reported in clinical trials. PMID:19271847

  7. Relating reconnection rate, exhaust structure and effective resistivity

    NASA Astrophysics Data System (ADS)

    Singh, Nagendra

    2014-03-01

    The magnetic reconnection structure consists of a central diffusion region (CDR) and a cone or wedge shaped reconnection exhaust containing accelerated plasma flows and electromagnetic fluctuations. We predict here the relationship among the exhaust half-cone angle (θe), the half width (w) of the CDR, the outflow velocity Vo, and the effective resistivity (ηeff), which includes the effects of all the nonideal terms in the generalized Ohm's law. The effective resistivity is defined as the ratio of reconnection electric field Erec to the current density Jy at the X point and it essentially represents the loss of momentum from the current-carrying plasma particles due to scattering by waves, their inertia or outflux from the CDR. The relation is checked against relevant results previously reported from laboratory experiments, space observations, and simulations, showing excellent agreement. The relation can be used for estimating the ad-hoc effective resistivity often used in magnetohydrodynamic modeling of reconnection.

  8. Oral antibiotics are effective for highly resistant hip arthroplasty infections.

    PubMed

    Cordero-Ampuero, José; Esteban, Jaime; García-Cimbrelo, Eduardo

    2009-09-01

    Infected arthroplasties reportedly have a lower eradication rate when caused by highly resistant and/or polymicrobial isolates and in these patients most authors recommend intravenous antibiotics. We asked whether two-stage revision with interim oral antibiotics could eradicate these infections. We prospectively followed 36 patients (mean age, 71.8 years) with late hip arthroplasty infections. Combinations of oral antibiotics were prescribed according to cultures, biofilm, and intracellular effectiveness. The minimum followup was 1 year (mean, 4.4 years; range, 1-12 years). We presumed eradication in the absence of clinical, serologic, and radiographic signs of infection. Infection was eradicated in all 13 patients with highly resistant bacteria who completed a two-stage protocol (10 with methicillin-resistant Staphylococci) and in eight of 11 patients treated with only the first stage (and six of nine with methicillin-resistant Staphylococci). Infection was eradicated in six of six patients with polymicrobial isolates (of sensitive and/or resistant bacteria) who completed a two-stage protocol and in five of seven with polymicrobial isolates treated with only the first surgery. The Harris hip score averaged 88.1 (range, 70-98) in patients who underwent reimplantation and 56.8 (range, 32-76) in patients who underwent resection arthroplasty. Long cycles of combined oral antibiotics plus a two-stage surgical exchange appear a promising alternative for infections by highly resistant bacteria, methicillin-resistant Staphylococci, and polymicrobial infections.

  9. Acute effects of resistance training with local vibration.

    PubMed

    Couto, B P; Silva, H R; Filho, A G; da Silveira Neves, S R; Ramos, M G; Szmuchrowski, L A; Barbosa, M P

    2013-09-01

    The aim of this study was to verify the acute effects of the application of local vibration on upper limbs during resistance training on the number of maximum repetitions, metabolic and hormonal responses. 32 volunteers performed a maximum voluntary contraction test during a lat pulldown exercise. After the test, all volunteers underwent one conventional resistance training session and one resistance training session with local vibration. In both interventions, volunteers performed 4 sets with the highest possible number of repetitions of the lat pulldown exercise at 55% of maximum voluntary contraction. During the vibratory resistance training intervention, vibration was locally applied (20-Hz and 12-mm). During the conventional resistance training, volunteers performed the same procedures without vibration. Blood samples were taken at each experimental session before and 5 min after the end of each intervention. No significant differences were observed in number of maximum repetitions between the series of vibratory and conventional training. Serum testosterone, cortisol and lactate were significantly increased after 2 interventions. Vibratory resistance training induced greater increases in testosterone and lactate concentrations. No significant changes were found in creatine kinase, creatinine or urea concentration. These data indicate that local vibration increases the metabolic and anabolic response to the resistance training, without changing the training volume. © Georg Thieme Verlag KG Stuttgart · New York.

  10. Effects of Raltegravir or Elvitegravir Resistance Signature Mutations on the Barrier to Dolutegravir Resistance In Vitro

    PubMed Central

    Seki, Takahiro; Suyama-Kagitani, Akemi; Kawauchi-Miki, Shinobu; Miki, Shigeru; Wakasa-Morimoto, Chiaki; Akihisa, Erika; Nakahara, Koichiro; Kobayashi, Masanori; Underwood, Mark R.; Sato, Akihiko; Fujiwara, Tamio

    2015-01-01

    The recently approved HIV-1 integrase strand transfer inhibitor (INSTI) dolutegravir (DTG) (S/GSK1349572) has overall advantageous activity when tested in vitro against HIV-1 with raltegravir (RAL) and elvitegravir (EVG) resistance signature mutations. We conducted an in vitro resistance selection study using wild-type HIV-1 and mutants with the E92Q, Y143C, Y143R, Q148H, Q148K, Q148R, and N155H substitutions to assess the DTG in vitro barrier to resistance. No viral replication was observed at concentrations of ≥32 nM DTG, whereas viral replication was observed at 160 nM RAL or EVG in the mutants. In the Q148H, Q148K, or Q148R mutants, G140S/Q148H, E138K/Q148K, E138K/Q148R, and G140S/Q148R secondary mutations were identified with each INSTI and showed high resistance to RAL or EVG but limited resistance to DTG. E138K and G140S, as secondary substitutions to Q148H, Q148K, or Q148R, were associated with partial recovery in viral infectivity and/or INSTI resistance. In the E92Q, Y143C, Y143R, and N155H mutants, no secondary substitutions were associated with DTG. These in vitro results suggest that DTG has a high barrier to the development of resistance in the presence of RAL or EVG signature mutations other than Q148. One explanation for this high barrier to resistance is that no additional secondary substitution of E92Q, Y143C, Y143R, or N155H simultaneously increased the fold change in 50% effective concentration (EC50) to DTG and infectivity. Although increased DTG resistance via the Q148 pathway and secondary substitutions occurs at low concentrations, a higher starting concentration may reduce or eliminate the development of DTG resistance in this pathway in vitro. PMID:25691633

  11. Cleanroom Energy Efficiency: Metrics and Benchmarks

    SciTech Connect

    International SEMATECH Manufacturing Initiative; Mathew, Paul A.; Tschudi, William; Sartor, Dale; Beasley, James

    2010-07-07

    Cleanrooms are among the most energy-intensive types of facilities. This is primarily due to the cleanliness requirements that result in high airflow rates and system static pressures, as well as process requirements that result in high cooling loads. Various studies have shown that there is a wide range of cleanroom energy efficiencies and that facility managers may not be aware of how energy efficient their cleanroom facility can be relative to other cleanroom facilities with the same cleanliness requirements. Metrics and benchmarks are an effective way to compare one facility to another and to track the performance of a given facility over time. This article presents the key metrics and benchmarks that facility managers can use to assess, track, and manage their cleanroom energy efficiency or to set energy efficiency targets for new construction. These include system-level metrics such as air change rates, air handling W/cfm, and filter pressure drops. Operational data are presented from over 20 different cleanrooms that were benchmarked with these metrics and that are part of the cleanroom benchmark dataset maintained by Lawrence Berkeley National Laboratory (LBNL). Overall production efficiency metrics for cleanrooms in 28 semiconductor manufacturing facilities in the United States and recorded in the Fabs21 database are also presented.

  12. Vestibular influence on auditory metrical interpretation.

    PubMed

    Phillips-Silver, Jessica; Trainor, Laurel J

    2008-06-01

    When we move to music we feel the beat, and this feeling can shape the sound we hear. Previous studies have shown that when people listen to a metrically ambiguous rhythm pattern, moving the body on a certain beat--adults, by actively bouncing themselves in synchrony with the experimenter, and babies, by being bounced passively in the experimenter's arms--can bias their auditory metrical representation so that they interpret the pattern in a corresponding metrical form [Phillips-Silver, J., & Trainor, L. J. (2005). Feeling the beat: Movement influences infant rhythm perception. Science, 308, 1430; Phillips-Silver, J., & Trainor, L. J. (2007). Hearing what the body feels: Auditory encoding of rhythmic movement. Cognition, 105, 533-546]. The present studies show that in adults, as well as in infants, metrical encoding of rhythm can be biased by passive motion. Furthermore, because movement of the head alone affected auditory encoding whereas movement of the legs alone did not, we propose that vestibular input may play a key role in the effect of movement on auditory rhythm processing. We discuss possible cortical and subcortical sites for the integration of auditory and vestibular inputs that may underlie the interaction between movement and auditory metrical rhythm perception.

  13. Ligand efficiency metrics considered harmful

    NASA Astrophysics Data System (ADS)

    Kenny, Peter W.; Leitão, Andrei; Montanari, Carlos A.

    2014-07-01

    Ligand efficiency metrics are used in drug discovery to normalize biological activity or affinity with respect to physicochemical properties such as lipophilicity and molecular size. This Perspective provides an overview of ligand efficiency metrics and summarizes thermodynamics of protein-ligand binding. Different classes of ligand efficiency metric are critically examined and the study concludes with suggestions for alternative ways to account for physicochemical properties when prioritizing and optimizing leads.

  14. Effect Sizes for Growth-Modeling Analysis for Controlled Clinical Trials in the Same Metric as for Classical Analysis

    ERIC Educational Resources Information Center

    Feingold, Alan

    2009-01-01

    The use of growth-modeling analysis (GMA)--including hierarchical linear models, latent growth models, and general estimating equations--to evaluate interventions in psychology, psychiatry, and prevention science has grown rapidly over the last decade. However, an effect size associated with the difference between the trajectories of the…

  15. PREDICTING THE ACUTE BEHAVIORAL EFFECTS OF TOLUENE INHALED FOR 24 HRS IN RATS: DOSE METRICS, METABOLISM AND BEHAVIORAL TOLERANCE

    EPA Science Inventory

    Purpose: Recent research on the acute effects of volatile organic compounds (VOCs) suggests that extrapolation from short (~ 1 h) to long durations (up to 4 h) is improved by using estimates of brain toluene concentration ( Br[ToI)] instead of cumulative inhaled dose (C x t) as a...

  16. Effect Sizes for Growth-Modeling Analysis for Controlled Clinical Trials in the Same Metric as for Classical Analysis

    ERIC Educational Resources Information Center

    Feingold, Alan

    2009-01-01

    The use of growth-modeling analysis (GMA)--including hierarchical linear models, latent growth models, and general estimating equations--to evaluate interventions in psychology, psychiatry, and prevention science has grown rapidly over the last decade. However, an effect size associated with the difference between the trajectories of the…

  17. PREDICTING THE ACUTE BEHAVIORAL EFFECTS OF TOLUENE INHALED FOR 24 HRS IN RATS: DOSE METRICS, METABOLISM AND BEHAVIORAL TOLERANCE

    EPA Science Inventory

    Purpose: Recent research on the acute effects of volatile organic compounds (VOCs) suggests that extrapolation from short (~ 1 h) to long durations (up to 4 h) is improved by using estimates of brain toluene concentration ( Br[ToI)] instead of cumulative inhaled dose (C x t) as a...

  18. Tissue concentrations as the dose metric to assess potential toxic effects of metals in field-collected fish: Copper and cadmium.

    PubMed

    Meador, James P

    2015-06-01

    The present study examined the available literature linking whole-body tissue concentrations with toxic effects in fish species for copper and cadmium. The variability in effect concentration for both copper and cadmium among species occurred within an order of magnitude for all responses, whereas the range for lethal toxicity based on water exposure spanned approximately 4 to 5 orders of magnitude. Fish tissue concentrations causing adverse effects were just above background concentrations, occurring between 1 μg/g and 10 μg/g for copper and 0.1 μg/g to 4 μg/g for cadmium. The results also show that salmonids are especially sensitive to cadmium, which appears to be a function of chemical potency. No studies were found that indicated adverse effects without increases in whole-body concentration of these metals. This narrow range for dose-response implies that a toxicological spillover point occurs when the detoxification capacity of various tissues within the animal are exceeded, and this likely occurs at a similar whole-body concentration for all naïvely exposed fish species. Elevated whole-body concentrations in fish from the field may be indicative of possible acclimation to metals that may or may not result in effects for target species. Acclimation concentrations may be useful in that they signal excessive metal concentrations in water, sediment, or prey species for a given site and indicate likely toxic effects for species unable to acclimate to excess metal exposure. Using tissue residues as the dose metric for these metals provides another line of evidence for assessing impaired ecosystems and greater confidence that hazard concentrations are protective for all fish species.

  19. Origins of effective resistivity in collisionless magnetic reconnection

    SciTech Connect

    Singh, Nagendra

    2014-07-15

    The mechanisms that provide effective resistivity for supporting collisonless magnetic reconnection have remained unsettled despite numerous studies. Some of these studies demonstrated that the electron pressure nongyrotropy generates the resistivity (η{sub npg}) in the electron diffusion region (EDR). We derive an analytical relation for the effective resistivity (η{sub kin}) by momentum balance in a control volume in the EDR. Both η{sub npg} and η{sub kin} mutually compare well and they also compare well with the resistivity required to support reconnection electric field E{sub rec} in multi-dimensional particle-in-cell simulations as well as in satellite observations when reconnection occurs in an EDR. But they are about an order of magnitude or so smaller than that required when the reconnection occurred in a much wider reconnecting current sheet (RCS) of half width (w) of the order of the ion skin depth (d{sub i}), observed in the Earth magnetosphere. The chaos-induced resistivity reported in the literature is found to be even more deficient. We find that for reconnection in RCS with w ∼ d{sub i}, anomalous diffusion, such as the universal Bhom diffusion and/or that arising from kinetic Alfven waves, could fairly well account for the required resistivity.

  20. Origins of effective resistivity in collisionless magnetic reconnection

    NASA Astrophysics Data System (ADS)

    Singh, Nagendra

    2014-07-01

    The mechanisms that provide effective resistivity for supporting collisonless magnetic reconnection have remained unsettled despite numerous studies. Some of these studies demonstrated that the electron pressure nongyrotropy generates the resistivity (ηnpg) in the electron diffusion region (EDR). We derive an analytical relation for the effective resistivity (ηkin) by momentum balance in a control volume in the EDR. Both ηnpg and ηkin mutually compare well and they also compare well with the resistivity required to support reconnection electric field Erec in multi-dimensional particle-in-cell simulations as well as in satellite observations when reconnection occurs in an EDR. But they are about an order of magnitude or so smaller than that required when the reconnection occurred in a much wider reconnecting current sheet (RCS) of half width (w) of the order of the ion skin depth (di), observed in the Earth magnetosphere. The chaos-induced resistivity reported in the literature is found to be even more deficient. We find that for reconnection in RCS with w ˜ di, anomalous diffusion, such as the universal Bhom diffusion and/or that arising from kinetic Alfven waves, could fairly well account for the required resistivity.

  1. Out of band radiation effects on resist patterning

    SciTech Connect

    George, Simi A .; Naulleau, Patrick P.

    2011-03-11

    Our previous work estimated the expected out-of-band (OOB) flare contribution at the wafer level assuming that there is a given amount of OOB at the collector focus. We found that the OOB effects are wavelength, resist, and pattern dependent. In this paper, results from rigorous patterning evaluation of multiple OOB-exposed resists using the SEMATECH Berkeley 0.3-NA MET are presented. A controlled amount of OOB is applied to the resist films before patterning is completed with the MET. LER and process performance above the resolution limit and at the resolution limits are evaluated and presented. The results typically show a negative impact on LER and process performance after the OOB exposures except in the case of single resist formulation, where resolution and performance improvement was observed.

  2. Effects of epilepsy treatments on sleep architecture and daytime sleepiness: an evidence-based review of objective sleep metrics.

    PubMed

    Jain, Sejal V; Glauser, Tracy A

    2014-01-01

    Sleep is considered restorative, and good quantity and quality sleep is required for memory consolidation and synaptic plasticity. Sleep disorders are common in patients with epilepsy. Poor sleep quality or quantity may worsen seizure control. On the other end, seizures and epilepsy may worsen the sleep quality and set a vicious cycle. In addition, antiepileptic drugs have an effect on sleep architecture. We performed a systemic literature review with a goal to evaluate the effect of antiepileptic drugs and nondrug treatments for epilepsy on sleep architecture to help better understand treatment effects, especially in patients with epilepsy and sleep problems. We searched PubMed and identified studies that evaluated objective sleep outcomes for an antiepileptic drug. We also searched for studies with objective sleep outcomes that evaluated other epilepsy treatments such as epilepsy surgery, vagus nerve stimulation, and ketogenic diet. The studies were categorized based on evidence class and study population for an individual antiepileptic drug or treatment. We identified that most antiepileptic drugs and nondrug treatments for epilepsy affect sleep architecture. We identified that gabapentin, tiagabine, pregabalin, clobazam, and carbamazepine reduce sleep latency and/or improve sleep efficiency. Phenobarbital, valproic acid, and higher-dose levetiracetam aggravate daytime sleepiness, whereas topiramate and zonisamide do not. Vagus nerve stimulation reduces daytime sleepiness, and ketogenic diet improves slow-wave sleep. Epilepsy surgery may improve nocturnal sleep only in a subgroup of patients with improved seizure frequency. Further studies are needed to evaluate the dose-dependent sleep effects of antiepileptic drugs and nondrug treatments independent of the improvement of epilepsy, and to identify if these changes are clinically significant. Wiley Periodicals, Inc. © 2013 International League Against Epilepsy.

  3. Use of historical data and a novel metric in the evaluation of the effectiveness of hearing conservation program components.

    PubMed

    Heyer, Nicholas; Morata, Thais C; Pinkerton, Lynne E; Brueck, Scott E; Stancescu, Daniel; Panaccio, Mary Prince; Kim, Hyoshin; Sinclair, J Stephen; Waters, Martha A; Estill, Cherie F; Franks, John R

    2011-07-01

    To evaluate the effectiveness of hearing conservation programs (HCP) and their specific components in reducing noise-induced hearing loss (NIHL). This retrospective cohort study was conducted at one food-processing plant and two automotive plants. Audiometric and work-history databases were combined with historical noise monitoring data to develop a time-dependent exposure matrix for each plant. Historical changes in production and HCP implementation were collected from company records, employee interviews and focus groups. These data were used to develop time-dependent quality assessments for various HCP components. 5478 male (30,427 observations) and 1005 female (5816 observations) subjects were included in the analysis. Analyses were conducted separately for males and females. Females tended to have less NIHL at given exposure levels than males. Duration of noise exposure stratified by intensity (dBA) was a better predictor of NIHL than the standard equivalent continuous noise level (L(eq)) based upon a 3-dBA exchange. Within this cohort, efficient dBA strata for males were <95 versus ≥ 95, and for females <90 versus ≥ 90. The reported enforced use of hearing protection devices (HPDs) significantly reduced NIHL. The data did not have sufficient within-plant variation to determine the effectiveness of noise monitoring or worker training. An association between increased audiometric testing and NIHL was believed to be an artifact of increased participation in screening. Historical audiometric data combined with noise monitoring data can be used to better understand the effectiveness of HCPs. Regular collection and maintenance of quality data should be encouraged and used to monitor the effectiveness of these interventions.

  4. Landscape pattern metrics and regional assessment

    USGS Publications Warehouse

    O'Neill, R. V.; Riitters, K.H.; Wickham, J.D.; Jones, K.B.

    1999-01-01

    The combination of remote imagery data, geographic information systems software, and landscape ecology theory provides a unique basis for monitoring and assessing large-scale ecological systems. The unique feature of the work has been the need to develop and interpret quantitative measures of spatial pattern-the landscape indices. This article reviews what is known about the statistical properties of these pattern metrics and suggests some additional metrics based on island biogeography, percolation theory, hierarchy theory, and economic geography. Assessment applications of this approach have required interpreting the pattern metrics in terms of specific environmental endpoints, such as wildlife and water quality, and research into how to represent synergystic effects of many overlapping sources of stress.

  5. Implementing the Metric System in Business Occupations. Metric Implementation Guide.

    ERIC Educational Resources Information Center

    Retzer, Kenneth A.; And Others

    Addressed to the business education teacher, this guide is intended to provide appropriate information, viewpoints, and attitudes regarding the metric system and to make suggestions regarding presentation of the material in the classroom. An introductory section on teaching suggestions emphasizes the need for a "think metric" approach made up of…

  6. Implementing the Metric System in Industrial Occupations. Metric Implementation Guide.

    ERIC Educational Resources Information Center

    Retzer, Kenneth A.

    Addressed to the industrial education teacher, this guide is intended to provide appropriate information, viewpoints, and attitudes regarding the metric system and to make suggestions regarding presentation of the material in the classroom. An introductory section on teaching suggestions emphasizes the need for a "think metric" approach made up of…

  7. Implementing the Metric System in Health Occupations. Metric Implementation Guide.

    ERIC Educational Resources Information Center

    Banks, Wilson P.; And Others

    Addressed to the health occupations education teacher, this guide is intended to provide appropriate information, viewpoints, and attitudes regarding the metric system and to make suggestions regarding presentation of the material in the classroom. An introductory section on teaching suggestions emphasizes the need for a "think metric" approach…

  8. Implementing the Metric System in Agricultural Occupations. Metric Implementation Guide.

    ERIC Educational Resources Information Center

    Gilmore, Hal M.; And Others

    Addressed to the agricultural education teacher, this guide is intended to provide appropriate information, viewpoints, and attitudes regarding the metric system and to make suggestions regarding presentation of the material in the classroom. An introductory section on teaching suggestions emphasizes the need for a "think metric" approach made up…

  9. Software metrics: Software quality metrics for distributed systems. [reliability engineering

    NASA Technical Reports Server (NTRS)

    Post, J. V.

    1981-01-01

    Software quality metrics was extended to cover distributed computer systems. Emphasis is placed on studying embedded computer systems and on viewing them within a system life cycle. The hierarchy of quality factors, criteria, and metrics was maintained. New software quality factors were added, including survivability, expandability, and evolvability.

  10. The Warburg effect and drug resistance

    PubMed Central

    Mohd Omar, Mohd Feroz; Soong, Richie

    2016-01-01

      The Warburg effect describes the increased utilization of glycolysis rather than oxidative phosphorylation by tumour cells for their energy requirements under physiological oxygen conditions. This effect has been the basis for much speculation on the survival advantage of tumour cells, tumourigenesis and the microenvironment of tumours. More recently, studies have begun to reveal how the Warburg effect could influence drug efficacy and how our understanding of tumour energetics could be exploited to improve drug development. In particular, evidence is emerging demonstrating how better modelling of the tumour metabolic microenvironment could lead to a better prediction of drug efficacy and the identification of new combination strategies. This review will provide details of the current understanding of the complex interplay between glucose metabolism and pharmacology and discuss opportunities for utilizing the Warburg effect in future drug development. PMID:26750865

  11. Effect of Mutation to Streptomycin Resistance on Amber Suppressor Genes

    PubMed Central

    Otsuji, Nozomu; Aono, Hiroyuki

    1968-01-01

    Three classes of nonidentical streptomycin-resistant mutations were distinguished in Escherichia coli by their effect on the efficiency of suppression by an amber suppressor gene, sup E. The first class of mutation caused a strong restriction in efficiency of suppression of an amber codon in various cistrons of phage λ and in an alkaline phosphatase structural gene of E. coli. The second class caused weak restriction, and the third class caused no restriction. The restrictive effect of the streptomycin resistance mutation of the first class on the sup E gene was reduced by addition of streptomycin. This mutation had little effect on efficiencies of suppression by amber suppressor genes sup D and sup F. Analyses on the alkaline phosphatase formed in the suppressor strain indicated that mutation to restrictive streptomycin resistance causes a reduction in translation of the amber codon in the alkaline phosphatase structural gene. Images PMID:4874314

  12. How inaccurate is weight as a metric for patient size? Comparing patient weight to effective diameter for size-specific dose estimation

    NASA Astrophysics Data System (ADS)

    Cook, Tessa S.; Chadalavada, Seetharam C.; Boonn, William W.

    2013-03-01

    One of the biggest challenges in dose monitoring is customization of CT dose estimates to the patient. Patient size remains a highly significant variable. One metric that has previously been used for patient size is patient weight, though this is often criticized as inaccurate. In this work, we compare patients' weight to their effective diameters obtained from a CT scan of the chest or the abdomen. CT exams of the chest (N=163) and abdomen/pelvis (N=168) performed on adult patients in July 2012 were randomly selected for analysis. The effective diameter of the patient for each exam was determined using the central slice of the scan region for each exam using eXposure™ (Radimetrics, Inc., Toronto, Canada). In some cases, the same patient had both a chest and abdominopelvic CT, so effective diameters from both regions were analyzed. In this small sample size, there appears to be a linear relationship between patient weight and effective diameter when measured in the mid-chest and mid-abdomen of adult patients. However, for each weight, patient effective diameter can vary by 5 cm from the regression line in both the chest and the abdomen. A 5-cm difference corresponds to a difference of approximately 0.2 in the chest and 0.3 in the abdomen/pelvis for the correction factors recommended for size-specific dose estimation by the AAPM. This preliminary data suggests that weight-based CT protocoling may in fact be appropriate for some adults. However, more work is needed to identify those patients in whom weight-based protocoling is not appropriate.

  13. Effects of sleeve gastrectomy on insulin resistance

    PubMed Central

    CĂTOI, ADRIANA FLORINELA; PÂRVU, ALINA; MIRONIUC, AUREL; GALEA, ROMEO FLORIN; MUREŞAN, ADRIANA; BIDIAN, CRISTINA; POP, IOANA

    2016-01-01

    Background and aim Obesity is a major risk factor for the onset of insulin resistance (IR), hyperinsulinemia and type 2 diabetes mellitus (T2DM) Evidence data has proven that beyond important weight loss bariatric surgery especially Roux-en-Y gastric bypass (RYGB) and bilio-pancreatic diversion (BPD) leads to significant early reduction of insulinemia and of IR calculated through the homeostatic model assessment (HOMA-IR), independently of fat mass decrease. Sleeve gastrectomy (SG) is now used as a sole weight loss operation with good results. Therefore, the aim of the present study was to investigate the early changes of fasting blood glucose, insulin and HOMA-IR in a group of morbidly obese (MO) patients i.e. at 7, 30 and 90 days after SG. Methods The study included 20 MO patients (7 male and 13 female) submitted to SG. Anthropometrical (weight, body mass index –BMI, percent excess BMI loss -%EBMIL) and biochemical (plasma glucose, insulin and calculated HOMA-IR ) evaluation were performed before and at 7, 30 and 90 days after SG. In addition, a second group of 10 normal weight healthy subjects with a BMI ranging form 19 kg/m2 to 23.14 kg/m2, matched for age and gender was investigated. Results Plasma glucose (p=0.018), insulin (p=0.004) and HOMA-IR (p=0.006) values were statistically different between the studied groups. After surgery, at every follow-up point, there were statistically different weight and BMI mean values relative to the operation day (p<0.003). BMI, decreased at 7 days (estimated reduction=2.79; 95% CI:[2.12;3.45]), at 30 days (estimated reduction=5.65; 95% CI:[3.57;7.73]) and at 90 days (estimated reduction=10.88; 95% CI:[7.35;14.41]) respectively after SG. We noted a tendency toward statistical significant change of mean insulin values at 7 days after surgery (corrected p=0.075), no statistical change at 30 days (corrected p=0.327) and a significant change at 90 days (corrected p=0.027) after SG as compared to baseline. There was a

  14. Measurable Control System Security through Ideal Driven Technical Metrics

    SciTech Connect

    Miles McQueen; Wayne Boyer; Sean McBride; Marie Farrar; Zachary Tudor

    2008-01-01

    The Department of Homeland Security National Cyber Security Division supported development of a small set of security ideals as a framework to establish measurable control systems security. Based on these ideals, a draft set of proposed technical metrics was developed to allow control systems owner-operators to track improvements or degradations in their individual control systems security posture. The technical metrics development effort included review and evaluation of over thirty metrics-related documents. On the bases of complexity, ambiguity, or misleading and distorting effects the metrics identified during the reviews were determined to be weaker than necessary to aid defense against the myriad threats posed by cyber-terrorism to human safety, as well as to economic prosperity. Using the results of our metrics review and the set of security ideals as a starting point for metrics development, we identified thirteen potential technical metrics - with at least one metric supporting each ideal. Two case study applications of the ideals and thirteen metrics to control systems were then performed to establish potential difficulties in applying both the ideals and the metrics. The case studies resulted in no changes to the ideals, and only a few deletions and refinements to the thirteen potential metrics. This led to a final proposed set of ten core technical metrics. To further validate the security ideals, the modifications made to the original thirteen potential metrics, and the final proposed set of ten core metrics, seven separate control systems security assessments performed over the past three years were reviewed for findings and recommended mitigations. These findings and mitigations were then mapped to the security ideals and metrics to assess gaps in their coverage. The mappings indicated that there are no gaps in the security ideals and that the ten core technical metrics provide significant coverage of standard security issues with 87% coverage. Based

  15. Environmental Decision Support with Consistent Metrics

    EPA Science Inventory

    One of the most effective ways to pursue environmental progress is through the use of consistent metrics within a decision making framework. The US Environmental Protection Agency’s Sustainable Technology Division has developed TRACI, the Tool for the Reduction and Assessment of...

  16. Metrication in Building Facilities for Production

    ERIC Educational Resources Information Center

    Manderville, L. E.

    1974-01-01

    Today's 868 foundries are designed around the equipment necessary for maximum production and safety. It follows that any change in the product manufactured has a definite effect on the building that houses it. Therefore, it is necessary that development of metrication in the construction industry must be coordinated with its development in…

  17. Environmental Decision Support with Consistent Metrics

    EPA Science Inventory

    One of the most effective ways to pursue environmental progress is through the use of consistent metrics within a decision making framework. The US Environmental Protection Agency’s Sustainable Technology Division has developed TRACI, the Tool for the Reduction and Assessment of...

  18. Effects of the Ebbinghaus illusion on different behaviors: one- and two-handed grasping; one- and two-handed manual estimation; metric and comparative judgment.

    PubMed

    Vishton, Peter M; Fabre, Edward

    2003-01-01

    Many studies have suggested that visually-guided action is largely immune to the effects of several pictorial illusions that strongly influence perceptual judgments. The judgments in these experiments, however, have usually involved comparisons of multiple elements within a display, whereas the visually-guided actions have typically involved a pincer grip directed to only one display element. The three experiments presented here assess the influence of this confound on the perception versus action illusion dissociation. In general, the studies suggest (a) that the confound affects perceptual judgment but not grasping or manual estimation, and (b) that difficult visuomotor tasks are more affected by the Ebbinghaus illusion than easier tasks. In Experiment 1, participants reached for or made judgments about plastic disks placed in the center of the Ebbinghaus illusion display. Some participants reached for or made judgments about only the disk on the right, whereas others reached for or judged both disks simultaneously. A large effect of the illusion was found for grasping and comparative judgment, but not for manual estimation or metric judgment. In Experiment 2, the disks were elevated slightly to make gripping the targets easier, and the effects of the illusion on grasping were greatly reduced. For Experiment 3, participants performed the manual estimation task while the hands were placed in view, on the surface of the table, and the effects of the illusion were significantly increased. Taken together, the experiments indicate that task difficulty and hand visibility affect whether a task will be influenced by pictorial illusions or not. One- and two-handed grasping seem to be affected approximately equally.

  19. Resistance training is medicine: effects of strength training on health.

    PubMed

    Westcott, Wayne L

    2012-01-01

    Inactive adults experience a 3% to 8% loss of muscle mass per decade, accompanied by resting metabolic rate reduction and fat accumulation. Ten weeks of resistance training may increase lean weight by 1.4 kg, increase resting metabolic rate by 7%, and reduce fat weight by 1.8 kg. Benefits of resistance training include improved physical performance, movement control, walking speed, functional independence, cognitive abilities, and self-esteem. Resistance training may assist prevention and management of type 2 diabetes by decreasing visceral fat, reducing HbA1c, increasing the density of glucose transporter type 4, and improving insulin sensitivity. Resistance training may enhance cardiovascular health, by reducing resting blood pressure, decreasing low-density lipoprotein cholesterol and triglycerides, and increasing high-density lipoprotein cholesterol. Resistance training may promote bone development, with studies showing 1% to 3% increase in bone mineral density. Resistance training may be effective for reducing low back pain and easing discomfort associated with arthritis and fibromyalgia and has been shown to reverse specific aging factors in skeletal muscle.

  20. Simulating the Effect of Spectroscopic MRI as a Metric for Radiation Therapy Planning in Patients with Glioblastoma

    PubMed Central

    Cordova, J. Scott; Kandula, Shravan; Gurbani, Saumya; Zhong, Jim; Tejani, Mital; Kayode, Oluwatosin; Patel, Kirtesh; Prabhu, Roshan; Schreibmann, Eduard; Crocker, Ian; Holder, Chad A.; Shim, Hyunsuk; Shu, Hui-Kuo

    2017-01-01

    Due to glioblastoma’s infiltrative nature, an optimal radiation therapy (RT) plan requires targeting infiltration not identified by anatomical magnetic resonance imaging (MRI). Here, high-resolution, whole-brain spectroscopic MRI (sMRI) is used to describe tumor infiltration alongside anatomical MRI and simulate the degree to which it modifies RT target planning. In 11 patients with glioblastoma, data from preRT sMRI scans were processed to give high-resolution, whole-brain metabolite maps normalized by contralateral white matter. Maps depicting choline to N-Acetylaspartate (Cho/NAA) ratios were registered to contrast-enhanced T1-weighted RT planning MRI for each patient. Volumes depicting metabolic abnormalities (1.5−, 1.75−, and 2.0-fold increases in Cho/NAA ratios) were compared with conventional target volumes and contrast-enhancing tumor at recurrence. sMRI-modified RT plans were generated to evaluate target volume coverage and organ-at-risk dose constraints. Conventional clinical target volumes and Cho/NAA abnormalities identified significantly different regions of microscopic infiltration with substantial Cho/NAA abnormalities falling outside of the conventional 60 Gy isodose line (41.1, 22.2, and 12.7 cm3, respectively). Clinical target volumes using Cho/NAA thresholds exhibited significantly higher coverage of contrast enhancement at recurrence on average (92.4%, 90.5%, and 88.6%, respectively) than conventional plans (82.5%). sMRI-based plans targeting tumor infiltration met planning objectives in all cases with no significant change in target coverage. In 2 cases, the sMRI-modified plan exhibited better coverage of contrast-enhancing tumor at recurrence than the original plan. Integration of the high-resolution, whole-brain sMRI into RT planning is feasible, resulting in RT target volumes that can effectively target tumor infiltration while adhering to conventional constraints. PMID:28105468

  1. Simulating the Effect of Spectroscopic MRI as a Metric for Radiation Therapy Planning in Patients with Glioblastoma.

    PubMed

    Cordova, J Scott; Kandula, Shravan; Gurbani, Saumya; Zhong, Jim; Tejani, Mital; Kayode, Oluwatosin; Patel, Kirtesh; Prabhu, Roshan; Schreibmann, Eduard; Crocker, Ian; Holder, Chad A; Shim, Hyunsuk; Shu, Hui-Kuo

    2016-12-01

    Due to glioblastoma's infiltrative nature, an optimal radiation therapy (RT) plan requires targeting infiltration not identified by anatomical magnetic resonance imaging (MRI). Here, high-resolution, whole-brain spectroscopic MRI (sMRI) is used to describe tumor infiltration alongside anatomical MRI and simulate the degree to which it modifies RT target planning. In 11 patients with glioblastoma, data from preRT sMRI scans were processed to give high-resolution, whole-brain metabolite maps normalized by contralateral white matter. Maps depicting choline to N-Acetylaspartate (Cho/NAA) ratios were registered to contrast-enhanced T1-weighted RT planning MRI for each patient. Volumes depicting metabolic abnormalities (1.5-, 1.75-, and 2.0-fold increases in Cho/NAA ratios) were compared with conventional target volumes and contrast-enhancing tumor at recurrence. sMRI-modified RT plans were generated to evaluate target volume coverage and organ-at-risk dose constraints. Conventional clinical target volumes and Cho/NAA abnormalities identified significantly different regions of microscopic infiltration with substantial Cho/NAA abnormalities falling outside of the conventional 60 Gy isodose line (41.1, 22.2, and 12.7 cm(3), respectively). Clinical target volumes using Cho/NAA thresholds exhibited significantly higher coverage of contrast enhancement at recurrence on average (92.4%, 90.5%, and 88.6%, respectively) than conventional plans (82.5%). sMRI-based plans targeting tumor infiltration met planning objectives in all cases with no significant change in target coverage. In 2 cases, the sMRI-modified plan exhibited better coverage of contrast-enhancing tumor at recurrence than the original plan. Integration of the high-resolution, whole-brain sMRI into RT planning is feasible, resulting in RT target volumes that can effectively target tumor infiltration while adhering to conventional constraints.

  2. Large-scale effects on resistivity index of porous media.

    PubMed

    Aggelopoulos, C; Klepetsanis, P; Theodoropoulou, M A; Pomoni, K; Tsakiroglou, C D

    2005-05-01

    The estimation of humidity in the unsaturated zone of soils and NAPL saturation in contaminated aquifers may be based on the interpretation of electrical resistivity index logs. In the present work, concepts of the theory of the two-phase flow in pore networks are employed to interpret the form of the equilibrium and dynamic resistivity index curves of large porous samples. A resistivity cell is constructed to measure the capillary and electrical properties of large samples of unconsolidated porous media. The drainage capillary pressure and resistivity index curves of a sand column are measured by using the micropore membrane (porous plate) method, where a 0.5% wt/vol NaCl aqueous solution is displaced by n-dodecane. The dynamic resistivity index curves are measured by using the continuous injection technique for various orientations of the sand column. Based on concepts of the two-phase flow theory, concerning the dominant displacement growth pattern in a pore network and arising from the cooperative effects of capillary, buoyancy, and viscous forces, approximate relationships are developed for the resistivity index and saturation exponent as functions of the water saturation. The saturation exponent decreases as the displacement advances and the fluid distribution across the sand column tends to be homogenized after oil breakthrough. Both the resistivity index and saturation exponent increase as the displacement pattern tends to become compact and stable. In the destabilized flow pattern, as the Bond number decreases, the resistivity index may increase respectably within a narrow range of values of the Bond number. This happens when the thickness of the unstable capillary finger exceeds the lateral dimension of the porous sample and becomes a fractal percolation cluster. The saturation exponent becomes almost constant and independent of water saturation only over the destabilized displacement pattern at high values of the Bond number.

  3. Multimetric indices: How many metrics?

    EPA Science Inventory

    Multimetric indices (MMI’s) often include 5 to 15 metrics, each representing a different attribute of assemblage condition, such as species diversity, tolerant taxa, and nonnative taxa. Is there an optimal number of metrics for MMIs? To explore this question, I created 1000 9-met...

  4. Metrical Phonology: German Sound System.

    ERIC Educational Resources Information Center

    Tice, Bradley S.

    Metrical phonology, a linguistic process of phonological stress assessment and diagrammatic simplification of sentence and word stress, is discussed as it is found in the English and German languages. The objective is to promote use of metrical phonology as a tool for enhancing instruction in stress patterns in words and sentences, particularly in…

  5. Metrics for Soft Goods Merchandising.

    ERIC Educational Resources Information Center

    Cooper, Gloria S., Ed.; Magisos, Joel H., Ed.

    Designed to meet the job-related metric measurement needs of students interested in soft goods merchandising, this instructional package is one of five for the marketing and distribution cluster, part of a set of 55 packages for metric instruction in different occupations. The package is intended for students who already know the occupational…

  6. Metrics for Hard Goods Merchandising.

    ERIC Educational Resources Information Center

    Cooper, Gloria S., Ed.; Magisos, Joel H., Ed.

    Designed to meet the job-related metric measurement needs of students interested in hard goods merchandising, this instructional package is one of five for the marketing and distribution cluster, part of a set of 55 packages for metric instruction in different occupations. The package is intended for students who already know the occupational…

  7. Metrication: A Guide for Consumers.

    ERIC Educational Resources Information Center

    Consumer and Corporate Affairs Dept., Ottawa (Ontario).

    The widespread use of the metric system by most of the major industrial powers of the world has prompted the Canadian government to investigate and consider use of the system. This booklet was developed to aid the consuming public in Canada in gaining some knowledge of metrication and how its application would affect their present economy.…

  8. Metrics--Libraries and Librarians

    ERIC Educational Resources Information Center

    Hall, Vivian S.; Anderson, Gregg

    1975-01-01

    The 1975 librarian must determine whether to begin collecting materials on the International System of Measurements (metric system). Librarians are urged to learn and use the metric system, provide displays, and collect materials to better serve their patrons. Bibliography. (Author/LS)

  9. Inching toward the Metric System.

    ERIC Educational Resources Information Center

    Moore, Randy

    1989-01-01

    Provides an overview and description of the metric system. Discusses the evolution of measurement systems and their early cultures, the beginnings of metric measurement, the history of measurement systems in the United States, the International System of Units, its general style and usage, and supplementary units. (RT)

  10. Numerical Calabi-Yau metrics

    NASA Astrophysics Data System (ADS)

    Douglas, Michael R.; Karp, Robert L.; Lukic, Sergio; Reinbacher, René

    2008-03-01

    We develop numerical methods for approximating Ricci flat metrics on Calabi-Yau hypersurfaces in projective spaces. Our approach is based on finding balanced metrics and builds on recent theoretical work by Donaldson. We illustrate our methods in detail for a one parameter family of quintics. We also suggest several ways to extend our results.

  11. How to Teach Metric Now.

    ERIC Educational Resources Information Center

    Worcester Public Schools, MA.

    This curriculum guide for grades K-6 was prepared to assist teachers and students in learning about the metric system. An introductory section presents a brief history of the metric system and the rationale for introducing it into the schools. Instructional objectives and suggested learning activities are presented for each grade level. The…

  12. Metric Activities, Grades K-6.

    ERIC Educational Resources Information Center

    Draper, Bob, Comp.

    This pamphlet presents worksheets for use in fifteen activities or groups of activities designed for teaching the metric system to children in grades K through 6. The approach taken in several of the activities is one of conversion between metric and English units. The majority of the activities concern length, area, volume, and capacity. A…

  13. What About Metric? Revised Edition.

    ERIC Educational Resources Information Center

    Barbrow, Louis E.

    Described are the advantages of using the metric system over the English system. The most common units of both systems are listed and compared. Pictures are used to exhibit use of the metric system in connection with giving prices or sizes of common items. Several examples provide computations of area, total weight of several objects, and volume;…

  14. Metric Supplement to Technical Drawing.

    ERIC Educational Resources Information Center

    Henschel, Mark

    This manual is intended for use in training persons whose vocations involve technical drawing to use the metric system of measurement. It could be used in a short course designed for that purpose or for individual study. The manual begins with a brief discussion of the rationale for conversion to the metric system. It then provides a…

  15. Metrication: A Guide for Consumers.

    ERIC Educational Resources Information Center

    Consumer and Corporate Affairs Dept., Ottawa (Ontario).

    The widespread use of the metric system by most of the major industrial powers of the world has prompted the Canadian government to investigate and consider use of the system. This booklet was developed to aid the consuming public in Canada in gaining some knowledge of metrication and how its application would affect their present economy.…

  16. [Reversing effects of emodin on multidrug resistance in resistant HL-60/ADR cells].

    PubMed

    Chen, Ying-Yu; Li, Jing; Hu, Jian-Da; Zheng, Jing; Zheng, Zhi-Hong; Zhu, Liang-Fang; Chen, Xin-Ji; Lin, Zhen-Xing

    2013-12-01

    This study was aimed to investigate the reversing effects of emodin on multidrug resistance (MDR) in resistant HL-60/ADR cells, and to explore the underlying mechanisms. The MTT assay was used to assess the chemoresistance of HL-60/ADR cells to emodin and 8 chemotherapeutic agents commonly used in clinic. The reversal effects of emodin on MDR of HL-60/ADR cells were also evaluated by MTT method. DNA ploidy analysis and DNA Ladder assay were used to detect apoptosis-induced effects on HL-60/ADR cells via the adriamycin (ADR) and emodin combination. The expression changes of the drug resistance-associated genes and proteins were detected by RT-PCR and Western Blot respectively. The intracellular accumulation and subcellular distribution of ADR and DNR were measured by flow cytometry and confocal laser scanning microscopy. The results showed that emodin inhibited HL-60/ADR cell proliferation with an average IC50 value of 24.09 ± 1.72 µmol/L, which was similar to that of the parental HL-60 cells (average IC50 = 23.18 ± 0.87 µmol/L). HL-60/ADR cells were resistant to a variety of chemotherapeutic agents, such as ADR, DNR, VP16, VCR,Ara-C, HHT, MTZ and THP. The reversal multiple were between 1.58 and 4.12 after the treatment with low concentration of emodin combined with the above mentioned different agents. The combination of ADR with emodin showed the best reversal effects, and the typical hypodiploid peak (apoptotic peak) and DNA ladder could be detected after the co-treatment.In addition, emodin down-regulated the mRNA and protein expression levels of MRP1, TOPOIIβ, GST π and BCL-2. Furthermore, the addition of emodin enhanced ADR and DNR intracellular accumulation and subcellular distribution in HL-60/ADR cells in dose-dependent manner. It is concluded that the emodin shows reversing effects on the multidrug resistant HL-60/ADR cells, possibly via decreasing the expression levels of drug resistance-associated genes, increasing the intracellular accumulation of

  17. Metrication report to the Congress

    NASA Technical Reports Server (NTRS)

    1989-01-01

    The major NASA metrication activity of 1988 concerned the Space Station. Although the metric system was the baseline measurement system for preliminary design studies, solicitations for final design and development of the Space Station Freedom requested use of the inch-pound system because of concerns with cost impact and potential safety hazards. Under that policy, however use of the metric system would be permitted through waivers where its use was appropriate. Late in 1987, several Department of Defense decisions were made to increase commitment to the metric system, thereby broadening the potential base of metric involvement in the U.S. industry. A re-evaluation of Space Station Freedom units of measure policy was, therefore, initiated in January 1988.

  18. Resistance to genetic insect control: Modelling the effects of space.

    PubMed

    Watkinson-Powell, Benjamin; Alphey, Nina

    2017-01-21

    Genetic insect control, such as self-limiting RIDL(2) (Release of Insects Carrying a Dominant Lethal) technology, is a development of the sterile insect technique which is proposed to suppress wild populations of a number of major agricultural and public health insect pests. This is achieved by mass rearing and releasing male insects that are homozygous for a repressible dominant lethal genetic construct, which causes death in progeny when inherited. The released genetically engineered ('GE') insects compete for mates with wild individuals, resulting in population suppression. A previous study modelled the evolution of a hypothetical resistance to the lethal construct using a frequency-dependent population genetic and population dynamic approach. This found that proliferation of resistance is possible but can be diluted by the introgression of susceptible alleles from the released homozygous-susceptible GE males. We develop this approach within a spatial context by modelling the spread of a lethal construct and resistance trait, and the effect on population control, in a two deme metapopulation, with GE release in one deme. Results show that spatial effects can drive an increased or decreased evolution of resistance in both the target and non-target demes, depending on the effectiveness and associated costs of the resistant trait, and on the rate of dispersal. A recurrent theme is the potential for the non-target deme to act as a source of resistant or susceptible alleles for the target deme through dispersal. This can in turn have a major impact on the effectiveness of insect population control.

  19. U.S. Metric Study Interim Report: Education.

    ERIC Educational Resources Information Center

    National Bureau of Standards (DOC), Washington, DC.

    This report is another in the series being prepared on the numerous investigations comprising the U. S. Metric Study, by the U. S. National Bureau of Standards. This report concerns the effects of increasing worldwide use of the metric system on education in the United States. Its purpose is to present the educational advantages and disadvantages…

  20. Education: U.S. Metric Study Interim Report.

    ERIC Educational Resources Information Center

    National Bureau of Standards (DOC), Washington, DC.

    This interim report, as the sixth in a series was prepared to provide a better basis for Congressional evaluation of the feasibility of a United States changeover to a metric system. This study concerning the effects of increasing worldwide use of the metric system on education in the United States was carried out by the Education Development…

  1. Resistive memory for harsh electronics: immunity to surface effect and high corrosion resistance via surface modification.

    PubMed

    Huang, Teng-Han; Yang, Po-Kang; Lien, Der-Hsien; Kang, Chen-Fang; Tsai, Meng-Lin; Chueh, Yu-Lun; He, Jr-Hau

    2014-03-18

    The tolerance/resistance of the electronic devices to extremely harsh environments is of supreme interest. Surface effects and chemical corrosion adversely affect stability and operation uniformity of metal oxide resistive memories. To achieve the surrounding-independent behavior, the surface modification is introduced into the ZnO memristors via incorporating fluorine to replace the oxygen sites. F-Zn bonds is formed to prevent oxygen chemisorption and ZnO dissolution upon corrosive atmospheric exposure, which effectively improves switching characteristics against harmful surroundings. In addition, the fluorine doping stabilizes the cycling endurance and narrows the distribution of switching parameters. The outcomes provide valuable insights for future nonvolatile memory developments in harsh electronics.

  2. Resistive Memory for Harsh Electronics: Immunity to Surface Effect and High Corrosion Resistance via Surface Modification

    NASA Astrophysics Data System (ADS)

    Huang, Teng-Han; Yang, Po-Kang; Lien, Der-Hsien; Kang, Chen-Fang; Tsai, Meng-Lin; Chueh, Yu-Lun; He-Hau, Jr.

    2014-03-01

    The tolerance/resistance of the electronic devices to extremely harsh environments is of supreme interest. Surface effects and chemical corrosion adversely affect stability and operation uniformity of metal oxide resistive memories. To achieve the surrounding-independent behavior, the surface modification is introduced into the ZnO memristors via incorporating fluorine to replace the oxygen sites. F-Zn bonds is formed to prevent oxygen chemisorption and ZnO dissolution upon corrosive atmospheric exposure, which effectively improves switching characteristics against harmful surroundings. In addition, the fluorine doping stabilizes the cycling endurance and narrows the distribution of switching parameters. The outcomes provide valuable insights for future nonvolatile memory developments in harsh electronics.

  3. Resistive Memory for Harsh Electronics: Immunity to Surface Effect and High Corrosion Resistance via Surface Modification

    PubMed Central

    Huang, Teng-Han; Yang, Po-Kang; Lien, Der-Hsien; Kang, Chen-Fang; Tsai, Meng-Lin; Chueh, Yu-Lun; He, Jr-Hau

    2014-01-01

    The tolerance/resistance of the electronic devices to extremely harsh environments is of supreme interest. Surface effects and chemical corrosion adversely affect stability and operation uniformity of metal oxide resistive memories. To achieve the surrounding-independent behavior, the surface modification is introduced into the ZnO memristors via incorporating fluorine to replace the oxygen sites. F-Zn bonds is formed to prevent oxygen chemisorption and ZnO dissolution upon corrosive atmospheric exposure, which effectively improves switching characteristics against harmful surroundings. In addition, the fluorine doping stabilizes the cycling endurance and narrows the distribution of switching parameters. The outcomes provide valuable insights for future nonvolatile memory developments in harsh electronics. PMID:24638086

  4. Weyl metrics and wormholes

    NASA Astrophysics Data System (ADS)

    Gibbons, Gary W.; Volkov, Mikhail S.

    2017-05-01

    We study solutions obtained via applying dualities and complexifications to the vacuum Weyl metrics generated by massive rods and by point masses. Rescaling them and extending to complex parameter values yields axially symmetric vacuum solutions containing singularities along circles that can be viewed as singular matter sources. These solutions have wormhole topology with several asymptotic regions interconnected by throats and their sources can be viewed as thin rings of negative tension encircling the throats. For a particular value of the ring tension the geometry becomes exactly flat although the topology remains non-trivial, so that the rings literally produce holes in flat space. To create a single ring wormhole of one metre radius one needs a negative energy equivalent to the mass of Jupiter. Further duality transformations dress the rings with the scalar field, either conventional or phantom. This gives rise to large classes of static, axially symmetric solutions, presumably including all previously known solutions for a gravity-coupled massless scalar field, as for example the spherically symmetric Bronnikov-Ellis wormholes with phantom scalar. The multi-wormholes contain infinite struts everywhere at the symmetry axes, apart from solutions with locally flat geometry.

  5. Effectiveness of Electroconvulsive Therapy Augmentation on Clozapine-Resistant Schizophrenia

    PubMed Central

    Kim, Hye Sung; Kim, Se Hyun; Lee, Nam Young; Youn, Tak; Lee, Jeoung Hyuk; Chung, Seunghyun; Kim, Yong Sik

    2017-01-01

    Objective This retrospective case series study of the effectiveness of electroconvulsive therapy (ECT) augmentation on clozapine-resistant schizophrenia was conducted by EMR review. Methods Clozapine-resistance was defined as persistent psychotic symptoms despite at least 12 weeks of clozapine administration with blood levels over 350 ng/mL in order to rule out pseudo-resistance. Seven in-patients who were taking clozapine and treated with ECT were selected. We analyzed the psychopathology and subscales changed by ECT. Results The average number of ECT sessions was 13.4 (±4.6). Total Positive and Negative Syndrome Scale (PANSS) score was significantly reduced by 17.9 (±12.8) points (p=0.0384) on average, which represented a reduction of 25.5% (±14.3). 71.4% (5/7) of patients were identified as clinical remission, with at least a 20% reduction in PANSS score. PANSS reduction was associated with number of ECT sessions, stimulus level in the final session, and blood clozapine levels before ECT. However, the negative subscale on the PANSS were not reduced by ECT in any patient. We did not observe any persistent adverse cognitive effects. Conclusion This study supports that ECT augmentation on clozapine-resistant schizophrenia reveals clinically effective and safe. Further research should be done involving a larger number of patients to investigate the effectiveness of clozapine/ECT combination therapy. PMID:28096876

  6. The effectiveness of child-resistant packaging for aspirin.

    PubMed

    Rodgers, Gregory B

    2002-09-01

    To evaluate the effectiveness of child-resistant packaging in reducing the mortality rate from the unintentional ingestion of aspirin for children younger than 5 years. Estimates of the annual aspirin-related mortality rate for children younger than 5 years in the United States were developed for the 1958-1990 study period. A multivariate negative binomial regression model was then used to estimate the independent effect of the packaging requirements on the child mortality rate during the postintervention period. The analysis controlled for changes in the per capita use of aspirin, long-term safety trends, and other extraneous and potentially confounding factors that may have affected the aspirin-related child mortality rate. Estimated percentage reduction in the child mortality rate associated with the use of child-resistant packaging. After controlling for covariates, the use of child-resistant packaging was associated with a 34% reduction in the aspirin-related child mortality rate. This mortality rate reduction equates to the prevention of about 90 child deaths during the 1973-1990 postregulatory study period. Child-resistant packaging has been effective in reducing aspirin-related child poisonings. However, because its effectiveness is only partial, further poison prevention strategies should be developed and instituted.

  7. Quantitative Metrics of Robustness in River Deltas

    NASA Astrophysics Data System (ADS)

    Foufoula-Georgiou, E.; Tejedor, A.; Longjas, A.; Zaliapin, I. V.

    2014-12-01

    Deltas are landforms with channels that deliver water, sediment and nutrient fluxes from rivers to oceans or inland water bodies via multiple pathways. We conceptualize a delta channel network as a rooted acyclic directed graph where channels are modeled by edges and junctions by vertices. We use spectral graph theory - mainly the geometry of the null space of the directed weighted graph Laplacian - to establish a quantitative framework for extracting important structural and dynamics-related information from river deltas. Using this information, we introduce refined metrics of system complexity, such as entropy. Entropy has been proven to be an important measure of the amount of uncertainty in stochastic systems, and therefore a surrogate of the capacity of the system to undergo changes. Here we present an entropic approach to evaluate the robustness of deltas, showing how the two components of entropy: mutual information and conditional entropy can be interpreted in this framework. We also present other metrics that include, among others, resistance distance and number of alternative paths, which quantify the structural complexity of the system. We use these metrics to better classify deltaic systems, quantify their resilience and propose possible management scenarios.

  8. Effect of electronic compensation on plethysmographic airway resistance measurements.

    PubMed

    Broughton, Simon; Rafferty, Gerrard F; Milner, Anthony D; Greenough, Anne

    2007-09-01

    To compare the performance of a plethysmograph which incorporated electronic compensation (Jaeger) to one which incorporated a heated humidified breathing system (Hammersmith plethysmograph). The performance of a plethysmograph which incorporated electronic compensation would be impaired compared to that which incorporated a heated humidified system. In vitro and in vivo comparison. Eleven children, median postnatal age 13 (range 5-15) months. In vitro, the plethysmographs were assessed using known resistances (1.94, 4.85, and 6.80 kPa, equivalent to 20, 50, and 70 cm H(2)O/L/sec, respectively). In vivo, comparison was made of the results of children studied in both plethysmographs. In vitro, the resistance results of the two plethysmographs were similar to each other and to the known resistances. In vivo, the median "effective" airways resistance result of the Jaeger (4.15 kPa/L/sec) was significantly higher than the inspiratory resistance of the Hammersmith plethysmograph (3.0 kPa/L/sec), but the median inspiratory resistances of the Jaeger were significantly lower than those of the Hammersmith plethysmograph (2.8 kPa/L/sec vs. 3.0 kPa/L/sec). The mean within patient coefficient of variability for inspiratory resistance of the Jaeger plethysmograph (16.7%) was significantly higher than that of the Hammersmith plethysmograph (11.6%) (P = 0.014). These results suggest plethysmographs which incorporate electronic compensation may be inappropriate for use in infants and very young children. (c) 2007 Wiley-Liss, Inc.

  9. Oral Antibiotics are Effective for Highly Resistant Hip Arthroplasty Infections

    PubMed Central

    Esteban, Jaime; García-Cimbrelo, Eduardo

    2009-01-01

    Infected arthroplasties reportedly have a lower eradication rate when caused by highly resistant and/or polymicrobial isolates and in these patients most authors recommend intravenous antibiotics. We asked whether two-stage revision with interim oral antibiotics could eradicate these infections. We prospectively followed 36 patients (mean age, 71.8 years) with late hip arthroplasty infections. Combinations of oral antibiotics were prescribed according to cultures, biofilm, and intracellular effectiveness. The minimum followup was 1 year (mean, 4.4 years; range, 1–12 years). We presumed eradication in the absence of clinical, serologic, and radiographic signs of infection. Infection was eradicated in all 13 patients with highly resistant bacteria who completed a two-stage protocol (10 with methicillin-resistant Staphylococci) and in eight of 11 patients treated with only the first stage (and six of nine with methicillin-resistant Staphylococci). Infection was eradicated in six of six patients with polymicrobial isolates (of sensitive and/or resistant bacteria) who completed a two-stage protocol and in five of seven with polymicrobial isolates treated with only the first surgery. The Harris hip score averaged 88.1 (range, 70–98) in patients who underwent reimplantation and 56.8 (range, 32–76) in patients who underwent resection arthroplasty. Long cycles of combined oral antibiotics plus a two-stage surgical exchange appear a promising alternative for infections by highly resistant bacteria, methicillin-resistant Staphylococci, and polymicrobial infections. Level of Evidence: Level IV, prognostic study. See Guidelines for Authors for a complete description of levels of evidence. PMID:19333670

  10. METRICS DEVELOPMENT FOR PATENTS.

    PubMed

    Veiga, Daniela Francescato; Ferreira, Lydia Masako

    2015-01-01

    To develop a proposal for metrics for patents to be applied in assessing the postgraduate programs of Medicine III - Capes. From the reading and analysis of the 2013 area documents of all the 48 areas of Capes, a proposal for metrics for patents was developed to be applied in Medicine III programs. Except for the areas Biotechnology, Food Science, Biological Sciences III, Physical Education, Engineering I, III and IV and Interdisciplinary, most areas do not adopt a scoring system for patents. The proposal developed was based on the criteria of Biotechnology, with adaptations. In general, it will be valued, in ascending order, the deposit, the granting and licensing/production. It will also be assigned higher scores to patents registered abroad and whenever there is a participation of students. This proposal can be applied to the item Intellectual Production of the evaluation form, in subsection Technical Production/Patents. The percentage of 10% for academic programs and 40% for Masters Professionals should be maintained. The program will be scored as Very Good when it reaches 400 points or over; Good, between 200 and 399 points; Regular, between 71 and 199 points; Weak up to 70 points; Insufficient, no punctuation. Desenvolver uma proposta de métricas para patentes a serem aplicadas na avaliação dos Programas de Pós-Graduação da Área Medicina III - Capes. A partir da leitura e análise dos documentos de área de 2013 de todas as 48 Áreas da Capes, desenvolveu-se uma proposta de métricas para patentes, a ser aplicada na avaliação dos programas da área. Constatou-se que, com exceção das áreas Biotecnologia, Ciência de Alimentos, Ciências Biológicas III, Educação Física, Engenharias I, III e IV e Interdisciplinar, a maioria não adota sistema de pontuação para patentes. A proposta desenvolvida baseou-se nos critérios da Biotecnologia, com adaptações. De uma forma geral, foi valorizado, em ordem crescente, o depósito, a concessão e o

  11. Variable metric conjugate gradient methods

    SciTech Connect

    Barth, T.; Manteuffel, T.

    1994-07-01

    1.1 Motivation. In this paper we present a framework that includes many well known iterative methods for the solution of nonsymmetric linear systems of equations, Ax = b. Section 2 begins with a brief review of the conjugate gradient method. Next, we describe a broader class of methods, known as projection methods, to which the conjugate gradient (CG) method and most conjugate gradient-like methods belong. The concept of a method having either a fixed or a variable metric is introduced. Methods that have a metric are referred to as either fixed or variable metric methods. Some relationships between projection methods and fixed (variable) metric methods are discussed. The main emphasis of the remainder of this paper is on variable metric methods. In Section 3 we show how the biconjugate gradient (BCG), and the quasi-minimal residual (QMR) methods fit into this framework as variable metric methods. By modifying the underlying Lanczos biorthogonalization process used in the implementation of BCG and QMR, we obtain other variable metric methods. These, we refer to as generalizations of BCG and QMR.

  12. A Metric for Heterotic Moduli

    NASA Astrophysics Data System (ADS)

    Candelas, Philip; de la Ossa, Xenia; McOrist, Jock

    2017-09-01

    Heterotic vacua of string theory are realised, at large radius, by a compact threefold with vanishing first Chern class together with a choice of stable holomorphic vector bundle. These form a wide class of potentially realistic four-dimensional vacua of string theory. Despite all their phenomenological promise, there is little understanding of the metric on the moduli space of these. What is sought is the analogue of special geometry for these vacua. The metric on the moduli space is important in phenomenology as it normalises D-terms and Yukawa couplings. It is also of interest in mathematics, since it generalises the metric, first found by Kobayashi, on the space of gauge field connections, to a more general context. Here we construct this metric, correct to first order in {α^{\\backprime}} , in two ways: first by postulating a metric that is invariant under background gauge transformations of the gauge field, and also by dimensionally reducing heterotic supergravity. These methods agree and the resulting metric is Kähler, as is required by supersymmetry. Checking the metric is Kähler is intricate and the anomaly cancellation equation for the H field plays an essential role. The Kähler potential nevertheless takes a remarkably simple form: it is the Kähler potential of special geometry with the Kähler form replaced by the {α^{\\backprime}} -corrected hermitian form.

  13. Enhanced oxidation resistance of active nanostructures via dynamic size effect

    NASA Astrophysics Data System (ADS)

    Liu, Yun; Yang, Fan; Zhang, Yi; Xiao, Jianping; Yu, Liang; Liu, Qingfei; Ning, Yanxiao; Zhou, Zhiwen; Chen, Hao; Huang, Wugen; Liu, Ping; Bao, Xinhe

    2017-02-01

    A major challenge limiting the practical applications of nanomaterials is that the activities of nanostructures (NSs) increase with reduced size, often sacrificing their stability in the chemical environment. Under oxidative conditions, NSs with smaller sizes and higher defect densities are commonly expected to oxidize more easily, since high-concentration defects can facilitate oxidation by enhancing the reactivity with O2 and providing a fast channel for oxygen incorporation. Here, using FeO NSs as an example, we show to the contrary, that reducing the size of active NSs can drastically increase their oxidation resistance. A maximum oxidation resistance is found for FeO NSs with dimensions below 3.2 nm. Rather than being determined by the structure or electronic properties of active sites, the enhanced oxidation resistance originates from the size-dependent structural dynamics of FeO NSs in O2. We find this dynamic size effect to govern the chemical properties of active NSs.

  14. GPS Metric Tracking Unit

    NASA Technical Reports Server (NTRS)

    2008-01-01

    As Global Positioning Satellite (GPS) applications become more prevalent for land- and air-based vehicles, GPS applications for space vehicles will also increase. The Applied Technology Directorate of Kennedy Space Center (KSC) has developed a lightweight, low-cost GPS Metric Tracking Unit (GMTU), the first of two steps in developing a lightweight, low-cost Space-Based Tracking and Command Subsystem (STACS) designed to meet Range Safety's link margin and latency requirements for vehicle command and telemetry data. The goals of STACS are to improve Range Safety operations and expand tracking capabilities for space vehicles. STACS will track the vehicle, receive commands, and send telemetry data through the space-based asset, which will dramatically reduce dependence on ground-based assets. The other step was the Low-Cost Tracking and Data Relay Satellite System (TDRSS) Transceiver (LCT2), developed by the Wallops Flight Facility (WFF), which allows the vehicle to communicate with a geosynchronous relay satellite. Although the GMTU and LCT2 were independently implemented and tested, the design collaboration of KSC and WFF engineers allowed GMTU and LCT2 to be integrated into one enclosure, leading to the final STACS. In operation, GMTU needs only a radio frequency (RF) input from a GPS antenna and outputs position and velocity data to the vehicle through a serial or pulse code modulation (PCM) interface. GMTU includes one commercial GPS receiver board and a custom board, the Command and Telemetry Processor (CTP) developed by KSC. The CTP design is based on a field-programmable gate array (FPGA) with embedded processors to support GPS functions.

  15. Modeling of organic thin film transistors: Effect of contact resistances

    NASA Astrophysics Data System (ADS)

    Natali, Dario; Fumagalli, Luca; Sampietro, Marco

    2007-01-01

    Field effect transistors require an Ohmic source contact and an Ohmic drain contact for ideal operation. In many real situations, however, and specifically in organic devices, the injection of charge carriers from metals into semiconductors can be an inefficient process that is non-Ohmic. This has an adverse impact on the performance of thin film transistors and makes the analysis of electrical measurements a complex task because contact effects need to be disentangled from transistor properties. This paper deals with the effects of non-Ohmic contacts on the modeling of organic transistors and gives specific rules on how to extract the real transistor parameters (mobility, threshold voltage, and contact resistances) using only electrical measurements. The method consists of a differential analysis of the transfer characteristic curves (current versus gate voltage) and exploits the different functional dependences of current on gate voltage which is induced by the presence of contact resistances. This paper fully covers the situations from constant carrier mobility to power law gate-voltage-dependent mobility, from constant contact resistance to gate-voltage-dependent contact resistance, and in the linear and in the saturation regime of the operation of the transistor. It also gives important criteria for the validation of the extracted parameters to assess whether the conditions for the application of the method are fulfilled. Examples of application to organic transistors showing various behaviors are given and discussed.

  16. Effect of Photoperiod On Permethrin Resistance In Aedes aegypti.

    PubMed

    Villanueva, O Karina; Ponce, Gustavo; Lopez, Beatriz; Gutierrez, Selene M; Rodriguez, Iram P; Reyes, Guadalupe; Saavedra, Karla J; Black, William C; Garcia, Julian; Beaty, Barry; Eisen, Lars; Flores, Adriana E

    2016-12-01

    Living organisms have been exposed to light-dark cycles that allowed them to adapt to different ecological niches. Circadian cycles affect hormone release, metabolism, and response to xenobiotic compounds. Current studies have shown that insect susceptibility to toxic agents depends on circadian cycles, mainly because the biochemical processes involved in detoxification and responses to oxidative stress are modulated by this process. The goal of this study was to determine the effect of photoperiod on resistance to permethrin in Aedes aegypti . Collections of Ae. aegypti from 4 locations in Yucatan, southern Mexico, were subjected to 2 different photoperiod schemes: dark (0 h light:24 h dark) and natural photoperiod (12 h light:12 h dark). The comparison of both photoperiods was evaluated with respect to permethrin resistance using bottle bioassays and by monitoring the possible mechanism related such as enzymatic activity and by the frequency of 2 knockdown resistance mutations in the voltage-dependent sodium channel gene (V1016I and F1534C). The susceptible strain was used as a reference. The mosquitoes in dark photoperiod showed a reduction in resistance to the pyrethroid. The α-esterases and glutathione S-transferase enzymatic activities showed lower levels in the dark photoperiod, and the frequencies of V1016I knockdown resistance mutation showed significant difference between photoperiod schemes.

  17. Double metric, generalized metric, and α' -deformed double field theory

    NASA Astrophysics Data System (ADS)

    Hohm, Olaf; Zwiebach, Barton

    2016-03-01

    We relate the unconstrained "double metric" of the "α' -geometry" formulation of double field theory to the constrained generalized metric encoding the spacetime metric and b -field. This is achieved by integrating out auxiliary field components of the double metric in an iterative procedure that induces an infinite number of higher-derivative corrections. As an application, we prove that, to first order in α' and to all orders in fields, the deformed gauge transformations are Green-Schwarz-deformed diffeomorphisms. We also prove that to first order in α' the spacetime action encodes precisely the Green-Schwarz deformation with Chern-Simons forms based on the torsionless gravitational connection. This seems to be in tension with suggestions in the literature that T-duality requires a torsionful connection, but we explain that these assertions are ambiguous since actions that use different connections are related by field redefinitions.

  18. Effects of sol aging on resistive switching behaviors of HfOx resistive memories

    NASA Astrophysics Data System (ADS)

    Hsu, Chih-Chieh; Sun, Jhen-Kai; Tsao, Che-Chang; Chen, Yu-Ting

    2017-03-01

    This work investigates effects of long-term sol-aging time on sol-gel HfOx resistive random access memories (RRAMs). A nontoxic solvent of ethanol is used to replace toxic 2-methoxyethanol, which is usually used in sol-gel processes. The top electrodes are fabricated by pressing indium balls onto the HfOx surface rather than by using conventional sputtering or evaporation processes. The maximum process temperature is limited to be 100 ℃. Therefore, influences of plasma and high temperature on HfOx film can be avoided. Under this circumstance, effects of sol aging time on the HfOx films can be more clearly studied. The current conduction mechanisms in low and high electric regions of the HfOx RRAM are found to be dominated by Ohmic conduction and trap-filled space charge limited conduction (TF-SCLC), respectively. When the sol aging time increases, the resistive switching characteristic of the HfOx layer becomes unstable and the transition voltage from Ohmic conduction to TF-SCLC is also increased. This suggests that an exceedingly long aging time will give a HfOx film with more defect states. The XPS results are consistent with FTIR analysis and they can further explain the unstable HfOx resistive switching characteristic induced by sol aging.

  19. The effective resistance between twisted superconducting filaments in tapes

    NASA Astrophysics Data System (ADS)

    Takács, S.; Iwakuma, M.; Funaki, K.

    2001-05-01

    We consider two mechanisms, which influence the effective resistance between crossing strands on flat cables or filaments in twisted tapes. The one-layer classical Rutherford-type cable and the tapes with twisted BSCCO filaments in silver matrix are taken as analogous cases. The amount of the matrix between strands or filaments increases the effective conductance compared with the direct current paths (determined by the touching area of the filaments). The increase factor is about two and can easily be suppressed by other effects, like the contact resistance between the superconductor and the matrix. The second mechanism is due to the existence of induced voltage between any points of crossing filaments. This leads to an additional effective conductance, proportional to the square of the total number of filaments. Both effects are not very important for isotropic superconductors, but due to the strong anisotropy of critical parameters they can dominate for high temperature superconductors. The first one may partially compensate the influence of the usually weaker critical current density perpendicular to the tape. The contribution due to the second effect can explain the higher resistivity of the matrix in BSCCO tapes compared with pure silver. It seems that to obtain low AC coupling losses in BSCCO tapes, structures with small filament number are required.

  20. Daylight metrics and energy savings

    SciTech Connect

    Mardaljevic, John; Heschong, Lisa; Lee, Eleanor

    2009-12-31

    The drive towards sustainable, low-energy buildings has increased the need for simple, yet accurate methods to evaluate whether a daylit building meets minimum standards for energy and human comfort performance. Current metrics do not account for the temporal and spatial aspects of daylight, nor of occupants comfort or interventions. This paper reviews the historical basis of current compliance methods for achieving daylit buildings, proposes a technical basis for development of better metrics, and provides two case study examples to stimulate dialogue on how metrics can be applied in a practical, real-world context.

  1. Truss Performance and Packaging Metrics

    NASA Technical Reports Server (NTRS)

    Mikulas, Martin M.; Collins, Timothy J.; Doggett, William; Dorsey, John; Watson, Judith

    2006-01-01

    In the present paper a set of performance metrics are derived from first principals to assess the efficiency of competing space truss structural concepts in terms of mass, stiffness, and strength, for designs that are constrained by packaging. The use of these performance metrics provides unique insight into the primary drivers for lowering structural mass and packaging volume as well as enabling quantitative concept performance evaluation and comparison. To demonstrate the use of these performance metrics, data for existing structural concepts are plotted and discussed. Structural performance data is presented for various mechanical deployable concepts, for erectable structures, and for rigidizable structures.

  2. In vitro biokinetics of chlorpromazine and the influence of different dose metrics on effect concentrations for cytotoxicity in Balb/c 3T3, Caco-2 and HepaRG cell cultures.

    PubMed

    Broeders, Jessica J W; Blaauboer, Bas J; Hermens, Joop L M

    2013-04-01

    The extrapolation of in vitro to in vivo toxicity data is a challenge. Differences in sensitivity between cell systems may be due to intrinsic properties of the cell but also because of differences in exposure. In this study, the cytotoxicity and biokinetics of the antipsychotic chlorpromazine (CPZ) were studied in in vitro assays using different cell types and exposure conditions. Different dose metrics were assessed to express the sensitivity to CPZ. The biokinetics of CPZ were measured in cell cultures of Balb/c 3T3, Caco-2 and HepaRG cells. Cytotoxicity was measured by Alamar Blue and expressed using different dose metrics, including the nominal, measured total and measured free CPZ medium concentrations. CPZ was taken up by the cells; the highest amounts in the cell compartments were found in the Caco-2 and HepaRG cells. CPZ was highly protein-bound in the Caco-2 cell medium containing 10% fetal bovine serum, resulting in lower bioavailable exposure concentrations. Moreover, also uptake into the cells strongly influenced the concentration in the medium. The Balb/c 3T3 cells were the most sensitive to the toxic effect of CPZ. The use of different dose metrics influenced the cytotoxicity results found in the three cell types. The data show that in comparing the sensitivity of the tested cell systems, the freely dissolved concentration is a more appropriate dose metric than total concentration in the medium. The ranking in sensitivity of the three cell types for CPZ was dependent on the dose metric used. Copyright © 2013 Elsevier Ltd. All rights reserved.

  3. Effect of bimaxillary surgery on adaptive condylar head remodeling: metric analysis and image interpretation using cone-beam computed tomography volume superimposition.

    PubMed

    Park, Soo-Byung; Yang, Yu-Mi; Kim, Yong-Il; Cho, Bong-Hae; Jung, Yun-Hoa; Hwang, Dae-Seok

    2012-08-01

    The aim of the present study was to use cone-beam computed tomography volume superimposition to investigate the effect of bimaxillary orthognathic surgery on condylar head remodeling. Using a retrospective study design, 2 investigators evaluated the cone-beam computed tomography data of subjects who had undergone Le Fort I osteotomy and mandibular setback surgery. The predictor variable was time, grouped as preoperative versus postoperative. The outcome variables were the measurement changes of the condylar heads and the distribution of the condylar head remodeling signs. Paired t and χ(2) tests were performed for the purposes of the 2-dimensional metric analysis and the condylar head remodeling distribution. P < .05 was considered significant. The sample was composed of 22 adults (11 men and 11 women, age 20.3 ± 3.2 years) diagnosed with skeletal Class III malocclusion. The intra- and interoperator reliabilities of the image interpretation showed substantial agreement, according to Cohen's kappa index. The condylar heights on the sagittal and coronal planes decreased after surgery. Bone resorption occurred predominantly in the anterior and superior areas on the sagittal plane, the superior and lateral areas on the coronal plane, and the anterolateral and posterolateral areas on the axial plane (P < .05). Bone formation was apparent only in the anteromedial area on the axial plane (P < .05). Bimaxillary orthognathic surgery caused a decrease in the condylar heights and condylar head remodeling. The cone-beam computed tomography volume superimposition method showed that the condylar head had undergone remodeling after bimaxillary surgery. Copyright © 2012 American Association of Oral and Maxillofacial Surgeons. Published by Elsevier Inc. All rights reserved.

  4. The LSST metrics analysis framework (MAF)

    NASA Astrophysics Data System (ADS)

    Jones, R. L.; Yoachim, Peter; Chandrasekharan, Srinivasan; Connolly, Andrew J.; Cook, Kem H.; Ivezic, Željko; Krughoff, K. S.; Petry, Catherine; Ridgway, Stephen T.

    2014-07-01

    We describe the Metrics Analysis Framework (MAF), an open-source python framework developed to provide a user-friendly, customizable, easily-extensible set of tools for analyzing data sets. MAF is part of the Large Synoptic Survey Telescope (LSST) Simulations effort. Its initial goal is to provide a tool to evaluate LSST Operations Simulation (OpSim) simulated surveys to help understand the effects of telescope scheduling on survey performance, however MAF can be applied to a much wider range of datasets. The building blocks of the framework are Metrics (algorithms to analyze a given quantity of data), Slicers (subdividing the overall data set into smaller data slices as relevant for each Metric), and Database classes (to access the dataset and read data into memory). We describe how these building blocks work together, and provide an example of using MAF to evaluate different dithering strategies. We also outline how users can write their own custom Metrics and use these within the framework.

  5. Vehicle Integrated Prognostic Reasoner (VIPR) Metric Report

    NASA Technical Reports Server (NTRS)

    Cornhill, Dennis; Bharadwaj, Raj; Mylaraswamy, Dinkar

    2013-01-01

    This document outlines a set of metrics for evaluating the diagnostic and prognostic schemes developed for the Vehicle Integrated Prognostic Reasoner (VIPR), a system-level reasoner that encompasses the multiple levels of large, complex systems such as those for aircraft and spacecraft. VIPR health managers are organized hierarchically and operate together to derive diagnostic and prognostic inferences from symptoms and conditions reported by a set of diagnostic and prognostic monitors. For layered reasoners such as VIPR, the overall performance cannot be evaluated by metrics solely directed toward timely detection and accuracy of estimation of the faults in individual components. Among other factors, overall vehicle reasoner performance is governed by the effectiveness of the communication schemes between monitors and reasoners in the architecture, and the ability to propagate and fuse relevant information to make accurate, consistent, and timely predictions at different levels of the reasoner hierarchy. We outline an extended set of diagnostic and prognostics metrics that can be broadly categorized as evaluation measures for diagnostic coverage, prognostic coverage, accuracy of inferences, latency in making inferences, computational cost, and sensitivity to different fault and degradation conditions. We report metrics from Monte Carlo experiments using two variations of an aircraft reference model that supported both flat and hierarchical reasoning.

  6. Standardised metrics for global surgical surveillance.

    PubMed

    Weiser, Thomas G; Makary, Martin A; Haynes, Alex B; Dziekan, Gerald; Berry, William R; Gawande, Atul A

    2009-09-26

    Public health surveillance relies on standardised metrics to evaluate disease burden and health system performance. Such metrics have not been developed for surgical services despite increasing volume, substantial cost, and high rates of death and disability associated with surgery. The Safe Surgery Saves Lives initiative of WHO's Patient Safety Programme has developed standardised public health metrics for surgical care that are applicable worldwide. We assembled an international panel of experts to develop and define metrics for measuring the magnitude and effect of surgical care in a population, while taking into account economic feasibility and practicability. This panel recommended six measures for assessing surgical services at a national level: number of operating rooms, number of operations, number of accredited surgeons, number of accredited anaesthesia professionals, day-of-surgery death ratio, and postoperative in-hospital death ratio. We assessed the feasibility of gathering such statistics at eight diverse hospitals in eight countries and incorporated them into the WHO Guidelines for Safe Surgery, in which methods for data collection, analysis, and reporting are outlined.

  7. Reuse metrics and measurement: A framework

    NASA Technical Reports Server (NTRS)

    Reifer, Donald J.

    1990-01-01

    The lessons learned and experience gleaned are described by those who have started to implement the reuse metrics and measurement framework used in controlling the development of common avionics and software for its affiliated aircraft programs. The framework was developed to permit the measurement of the long term cost/benefits resulting from the creation and use of Reusable Software Objects (RSOs). The framework also monitors the efficiency and effectiveness of the Software Reuse Library (SRL). The metrics and measurement framework is defined which was established to allow some determinations and findings to be made relative to software reuse. Seven criteria are discussed which were used to guide the establishment of the proposed reuse framework. Object recapture and creation metrics are explained along with their normalized use in effort, productivity, and quality determination. A single and multiple reuse instance version of a popular cost model is presented which uses these metrics and the measurement scheme proposed to predict the software effort and duration under various reuse assumptions. Studies in using this model to predict actuals taken from the RCI data base of over 1000 completed projects is discussed.

  8. Edge effect on resistance scaling rules in graphene nanostructures.

    PubMed

    Xu, Guangyu; Torres, Carlos M; Tang, Jianshi; Bai, Jingwei; Song, Emil B; Huang, Yu; Duan, Xiangfeng; Zhang, Yuegang; Wang, Kang L

    2011-03-09

    We report an experimental investigation of the edge effect on the room-temperature transport in graphene nanoribbon and graphene sheet (both single-layer and bilayer). By measuring the resistance scaling behaviors at both low- and high-carrier densities, we show that the transport of single-layer nanoribbons lies in a strong localization regime, which can be attributed to an edge effect. We find that this edge effect can be weakened by enlarging the width, decreasing the carrier densities, or adding an extra layer. From graphene nanoribbon to graphene sheet, the data show a dimensional crossover of the transport regimes possibly due to the drastic change of the edge effect.

  9. Effect of ambient on the resistance fluctuations of graphene

    NASA Astrophysics Data System (ADS)

    Amin, Kazi Rafsanjani; Bid, Aveek

    2015-05-01

    In this letter, we present the results of systematic experimental investigations of the effect of different chemical environments on the low frequency resistance fluctuations of single layer graphene field effect transistors. The shape of the power spectral density of noise was found to be determined by the energetics of the adsorption-desorption of molecules from the graphene surface making it the dominant source of noise in these devices. We also demonstrate a method of quantitatively determining the adsorption energies of chemicals on graphene surface based on noise measurements. We find that the magnitude of noise is extremely sensitive to the nature and amount of the chemical species present. We propose that a chemical sensor based on the measurement of low frequency resistance fluctuations of single layer graphene field effect transistor devices will have extremely high sensitivity, very high specificity, high fidelity, and fast response times.

  10. A multi-metric assessment of environmental contaminant exposure and effects in an urbanized reach of the Charles River near Watertown, Massachusetts

    USGS Publications Warehouse

    Smith, Stephen B.; Anderson, Patrick J.; Baumann, Paul C.; DeWeese, Lawrence R.; Goodbred, Steven L.; Coyle, James J.; Smith, David S.

    2012-01-01

    The Charles River Project provided an opportunity to simultaneously deploy a combination of biomonitoring techniques routinely used by the U.S. Geological Survey National Water Quality Assessment Program, the Biomonitoring of Environmental Status and Trends Project, and the Contaminant Biology Program at an urban site suspected to be contaminated with polycyclic aromatic hydrocarbons. In addition to these standardized methods, additional techniques were used to further elucidate contaminant exposure and potential impacts of exposure on biota. The purpose of the study was to generate a comprehensive, multi-metric data set to support assessment of contaminant exposure and effects at the site. Furthermore, the data set could be assessed to determine the relative performance of the standardized method suites typically used by the National Water Quality Assessment Program and the Biomonitoring of Environmental Status and Trends Project, as well as the additional biomonitoring methods used in the study to demonstrate ecological effects of contaminant exposure. The Contaminant Effects Workgroup, an advisory committee of the U.S. Geological Survey/Contaminant Biology Program, identified polycyclic aromatic hydrocarbons as the contaminant class of greatest concern in urban streams of all sizes. The reach of the Charles River near Watertown, Massachusetts, was selected as the site for this study based on the suspected presence of polycyclic aromatic hydrocarbon contamination and the presence of common carp (Cyprinus carpio), largemouth bass (Micropterus salmoides), and white sucker (Catostomus commersoni). All of these fish have extensive contaminant-exposure profiles related to polycyclic aromatic hydrocarbons and other environmental contaminants. This project represented a collaboration of universities, Department of the Interior bureaus including multiple components of the USGS (Biological Resources Discipline and Water Resources Discipline Science Centers, the

  11. Effect of specific resistance training on overarm throwing performance.

    PubMed

    Ettema, Gertjan; Glosen, Tommy; van den Tillaar, Roland

    2008-06-01

    The main purpose of this study was to compare the effect of a specific resistance training program (throwing movement with a pulley device) with the effect of regular training (throwing with regular balls) on overarm throwing velocity under various conditions. The training forms were matched for total training load, ie, impulse generated on the ball or pulley device. Both training groups (resistance training n = 7 and regular training n = 6) consisted of women team handball players, and trained 3 times per week for 8 weeks, according to an assigned training program alongside their normal handball training. An increase in throwing velocity with normal balls after the training period was observed for both groups (P = .014), as well as throwing with heavier balls and throwing like actions in the pulley device. Although the regular training group seemed to improve more (6.1%) in throwing velocity with normal balls than the resistance training group (1.4%), this difference was not statistically significant. These findings indicate that resistance training does not surpass standard throwing training in improvement of overarm throwing velocity.

  12. Using TRACI for Sustainability Metrics

    EPA Science Inventory

    TRACI, the Tool for the Reduction and Assessment of Chemical and other environmental Impacts, has been developed for sustainability metrics, life cycle impact assessment, and product and process design impact assessment for developing increasingly sustainable products, processes,...

  13. Let's Make Metric Ice Cream

    ERIC Educational Resources Information Center

    Zimmerman, Marianna

    1975-01-01

    Describes a classroom activity which involved sixth grade students in a learning situation including making ice cream, safety procedures in a science laboratory, calibrating a thermometer, using metric units of volume and mass. (EB)

  14. Sizing Up the Metric System.

    ERIC Educational Resources Information Center

    Sherman, Helene J.

    1997-01-01

    Presents estimation as a tool for learning observation and measurement relationships for the metric system. Activities include constructing a meter tape and using mystery boxes to practice volume estimation and measurement. (AIM)

  15. Let's Make Metric Ice Cream

    ERIC Educational Resources Information Center

    Zimmerman, Marianna

    1975-01-01

    Describes a classroom activity which involved sixth grade students in a learning situation including making ice cream, safety procedures in a science laboratory, calibrating a thermometer, using metric units of volume and mass. (EB)

  16. Using TRACI for Sustainability Metrics

    EPA Science Inventory

    TRACI, the Tool for the Reduction and Assessment of Chemical and other environmental Impacts, has been developed for sustainability metrics, life cycle impact assessment, and product and process design impact assessment for developing increasingly sustainable products, processes,...

  17. Costs of antibiotic resistance – separating trait effects and selective effects

    PubMed Central

    Hall, Alex R; Angst, Daniel C; Schiessl, Konstanze T; Ackermann, Martin

    2015-01-01

    Antibiotic resistance can impair bacterial growth or competitive ability in the absence of antibiotics, frequently referred to as a ‘cost’ of resistance. Theory and experiments emphasize the importance of such effects for the distribution of resistance in pathogenic populations. However, recent work shows that costs of resistance are highly variable depending on environmental factors such as nutrient supply and population structure, as well as genetic factors including the mechanism of resistance and genetic background. Here, we suggest that such variation can be better understood by distinguishing between the effects of resistance mechanisms on individual traits such as growth rate or yield (‘trait effects’) and effects on genotype frequencies over time (‘selective effects’). We first give a brief overview of the biological basis of costs of resistance and how trait effects may translate to selective effects in different environmental conditions. We then review empirical evidence of genetic and environmental variation of both types of effects and how such variation may be understood by combining molecular microbiological information with concepts from evolution and ecology. Ultimately, disentangling different types of costs may permit the identification of interventions that maximize the cost of resistance and therefore accelerate its decline. PMID:25861384

  18. Metric Selection for Ecosystem Restoration

    DTIC Science & Technology

    2013-06-01

    Conceptual modeling can be used in a situation where there is little funding for monitoring and evaluation planning, and when planning needs to be done...ecosystem restoration monitoring and evaluation programs, compile a list of these previous metrics, and assess and narrow them down based on...and understanding of the system will likely correlate with the benefits gained from monitoring and evaluation . A more appropriate, robust metric

  19. Electromagnetic Metrics of Mental Workload.

    DTIC Science & Technology

    1987-09-01

    D-AiBS 285 ELECTROMAGNETIC METRICS OF MENTAL AdORIKLOAD(U) PURDUE t/, UNIV LAFAYETTE IN EEG SIGNAL PROCESSING LRB RUNON ET AL SEP 87 AFOSR-TR-87-ib.3...ACCESSION NO 61102F 2313 A4 11 TITLE (Include Security Claiwfication) Electromagnetic Metrics of Mental Workload (U) 12 PERSONAL AUTHOR(S) Aunon, J. I...sustained high level of workload can lead to mental exhaustion. Previous research has indicated that heart rate lariability and evoked potentials in

  20. Coverage Metrics for Model Checking

    NASA Technical Reports Server (NTRS)

    Penix, John; Visser, Willem; Norvig, Peter (Technical Monitor)

    2001-01-01

    When using model checking to verify programs in practice, it is not usually possible to achieve complete coverage of the system. In this position paper we describe ongoing research within the Automated Software Engineering group at NASA Ames on the use of test coverage metrics to measure partial coverage and provide heuristic guidance for program model checking. We are specifically interested in applying and developing coverage metrics for concurrent programs that might be used to support certification of next generation avionics software.

  1. Validity of ligand efficiency metrics.

    PubMed

    Murray, Christopher W; Erlanson, Daniel A; Hopkins, Andrew L; Keserü, György M; Leeson, Paul D; Rees, David C; Reynolds, Charles H; Richmond, Nicola J

    2014-06-12

    A recent viewpoint article (Improving the plausibility of success with inefficient metrics. ACS Med. Chem. Lett. 2014, 5, 2-5) argued that the standard definition of ligand efficiency (LE) is mathematically invalid. In this viewpoint, we address this criticism and show categorically that the definition of LE is mathematically valid. LE and other metrics such as lipophilic ligand efficiency (LLE) can be useful during the multiparameter optimization challenge faced by medicinal chemists.

  2. A universal metric for ferroic energy materials.

    PubMed

    Brück, Ekkes; Yibole, Hargen; Zhang, Lian

    2016-08-13

    After almost 20 years of intensive research on magnetocaloric effects near room temperature, magnetic refrigeration with first-order magnetocaloric materials has come close to real-life applications. Many materials have been discussed as potential candidates to be used in multicaloric devices. However, phase transitions in ferroic materials are often hysteretic and a metric is needed to estimate the detrimental effects of this hysteresis. We propose the coefficient of refrigerant performance, which compares the net work in a reversible cycle with the positive work on the refrigerant, as a universal metric for ferroic materials. Here, we concentrate on examples from magnetocaloric materials and only consider one barocaloric experiment. This is mainly due to lack of data on electrocaloric materials. It appears that adjusting the field-induced transitions and the hysteresis effects can minimize the losses in first-order materials.This article is part of the themed issue 'Taking the temperature of phase transitions in cool materials'.

  3. A universal metric for ferroic energy materials

    PubMed Central

    Yibole, Hargen; Zhang, Lian

    2016-01-01

    After almost 20 years of intensive research on magnetocaloric effects near room temperature, magnetic refrigeration with first-order magnetocaloric materials has come close to real-life applications. Many materials have been discussed as potential candidates to be used in multicaloric devices. However, phase transitions in ferroic materials are often hysteretic and a metric is needed to estimate the detrimental effects of this hysteresis. We propose the coefficient of refrigerant performance, which compares the net work in a reversible cycle with the positive work on the refrigerant, as a universal metric for ferroic materials. Here, we concentrate on examples from magnetocaloric materials and only consider one barocaloric experiment. This is mainly due to lack of data on electrocaloric materials. It appears that adjusting the field-induced transitions and the hysteresis effects can minimize the losses in first-order materials. This article is part of the themed issue ‘Taking the temperature of phase transitions in cool materials’. PMID:27402924

  4. Degraded visual environment image/video quality metrics

    NASA Astrophysics Data System (ADS)

    Baumgartner, Dustin D.; Brown, Jeremy B.; Jacobs, Eddie L.; Schachter, Bruce J.

    2014-06-01

    A number of image quality metrics (IQMs) and video quality metrics (VQMs) have been proposed in the literature for evaluating techniques and systems for mitigating degraded visual environments. Some require both pristine and corrupted imagery. Others require patterned target boards in the scene. None of these metrics relates well to the task of landing a helicopter in conditions such as a brownout dust cloud. We have developed and used a variety of IQMs and VQMs related to the pilot's ability to detect hazards in the scene and to maintain situational awareness. Some of these metrics can be made agnostic to sensor type. Not only are the metrics suitable for evaluating algorithm and sensor variation, they are also suitable for choosing the most cost effective solution to improve operating conditions in degraded visual environments.

  5. Effect of fat loss on arterial elasticity in obese adolescents with clinical insulin resistance: RESIST study.

    PubMed

    Ho, Mandy; Gow, Megan; Baur, Louise A; Benitez-Aguirre, Paul Z; Tam, Charmaine S; Donaghue, Kim C; Craig, Maria E; Cowell, Chris T; Garnett, Sarah P

    2014-10-01

    Reduced arterial elasticity contributes to an obesity-related increase in cardiovascular risk in adults. To evaluate the effect of fat loss on arterial elasticity in obese adolescents at risk of type 2 diabetes. A secondary data analysis of the RESIST study was performed in two hospitals in Sydney, Australia. The study included 56 subjects (ages, 10 to 17 y; 25 males) with prediabetes and/or clinical features of insulin resistance. A 12-month lifestyle plus metformin intervention. Arterial elasticity and systemic vascular resistance were measured using radial tonometry pulse contour analysis, percentage body fat (%BF) was measured by dual-energy x-ray absorptiometry, and insulin sensitivity index was derived from an oral glucose tolerance test and lipids. Adolescents (n = 31) with decreased %BF (mean change [range], -4.4% [-18.3 to -0.01%]) after the intervention had significant increases in the mean large arterial elasticity index (mean change [95%CI], 5.1 [1.9 to 8.2] mL/mm Hg * 10; P = .003) and insulin sensitivity index (0.5 [0.1 to 0.9]; P = .010) and a decrease in systemic vascular resistance (-82 [-129 to -35] dyne * s * cm(-5); P = .001). There were no significant changes in these parameters in adolescents who increased their %BF. Nor was there any significant change in the mean small arterial elasticity index in either group. Long-term follow-up of these adolescents is warranted to assess whether the observed changes in vascular elasticity will lead to a clinical benefit including reduced cardiovascular morbidity and mortality.

  6. Relating reconnection rate, exhaust structure and effective resistivity

    SciTech Connect

    Singh, Nagendra

    2014-03-15

    The magnetic reconnection structure consists of a central diffusion region (CDR) and a cone or wedge shaped reconnection exhaust containing accelerated plasma flows and electromagnetic fluctuations. We predict here the relationship among the exhaust half-cone angle (θ{sub e}), the half width (w) of the CDR, the outflow velocity V{sub o}, and the effective resistivity (η{sub eff}), which includes the effects of all the nonideal terms in the generalized Ohm's law. The effective resistivity is defined as the ratio of reconnection electric field E{sub rec} to the current density J{sub y} at the X point and it essentially represents the loss of momentum from the current-carrying plasma particles due to scattering by waves, their inertia or outflux from the CDR. The relation is checked against relevant results previously reported from laboratory experiments, space observations, and simulations, showing excellent agreement. The relation can be used for estimating the ad-hoc effective resistivity often used in magnetohydrodynamic modeling of reconnection.

  7. Effect of cigarette smoking on insulin resistance risk.

    PubMed

    Haj Mouhamed, D; Ezzaher, A; Neffati, F; Douki, W; Gaha, L; Najjar, M F

    2016-02-01

    Smoking is one of the main risk factors for cardiovascular disease (CVD). The mechanism(s) of the effects of smoking on CVD are not clearly understood; however, a number of atherogenic characteristics, such as insulin resistance have been reported. We aim to investigate the effects of cigarette smoking on insulin resistance and to determine the correlation between this parameter with smoking status characteristics. This study was conducted on 138 non-smokers and 162 smokers aged respectively 35.6±16.0 and 38.5±21.9 years. All subjects are not diabetic. Fasting glucose was determined by enzymatic methods and insulin by chemiluminescence method. Insulin resistance (IR) was estimated using the Homeostasis Model of Assessment equation: HOMA-IR=[fasting insulin (mU/L)×fasting glucose (mmol/L)]/22.5. IR was defined as the upper quartile of HOMA-IR. Values above 2.5 were taken as abnormal and reflect insulin resistance. Compared to non-smokers, smokers had significantly higher levels of fasting glucose, fasting insulin and HOMA-IR index. These associations remained significant after adjustment for confounding factors (age, gender, BMI and alcohol consumption). A statistically significant association was noted between the smoking status parameters, including both the number of cigarettes smoked/day and the duration of smoking, and fasting insulin levels as well for HOMA-IR index. Among smokers, we noted a positive correlation between HOMA-IR index and both plasma thiocyanates and urinary cotinine. Our results show that smokers have a high risk to developing an insulin resistance and hyperinsulinemia, compared with a matched group of non-smokers, and may help to explain the high risk of cardiovascular diseases in smokers. Copyright © 2015. Published by Elsevier SAS.

  8. A study for polarized illumination effects in photo resist

    NASA Astrophysics Data System (ADS)

    Lei, Junjiang; Bai, Min; Shiely, Jim; Zhang, Lin

    2005-06-01

    Using a polarized illumination source is a promising RET technique for improvement of wafer printability for features of 65 nm and below. Polarization effects could be considered in several different stages of lithography modeling and simulation. For example, light propagation in thin films, wave superstition and interference in the thin film stack, and mask-induced polarization all deserve special attention and delicate treatment because TE and TM waves have different behaviors through these stages. In this paper we consider effects of polarized illumination in photo resist, using the Kirchhoff approximation for masks. We discuss some theoretical aspects of our vector modeling methods and show an example of simulation for polarized illumination effects.

  9. Study of parasitic resistance effects in nanowire and nanoribbon biosensors.

    PubMed

    Zeimpekis, Ioannis; Sun, Kai; Hu, Chunxiao; Thomas, Owain; de Planque, Maurits Rr; Chong, Harold Mh; Morgan, Hywel; Ashburn, Peter

    2015-01-01

    In this work, we investigate sensor design approaches for eliminating the effects of parasitic resistance in nanowire and nanoribbon biosensors. Measurements of pH with polysilicon nanoribbon biosensors are used to demonstrate a reduction in sensitivity as the sensor length is reduced. The sensitivity (normalised conductance change) is reduced from 11% to 5.5% for a pH change from 9 to 3 as the sensing window length is reduced from 51 to 11 μm. These results are interpreted using a simple empirical model, which is also used to demonstrate how the sensitivity degradation can be alleviated by a suitable choice of sensor window length. Furthermore, a differential sensor design is proposed that eliminates the detrimental effects of parasitic resistance. Measurements on the differential sensor give a sensitivity of 15%, which is in good agreement with the predicted maximum sensitivity obtained from modeling.

  10. Fast plasma heating by anomalous and inertial resistivity effects

    NASA Technical Reports Server (NTRS)

    Duijveman, A.; Hoyng, P.; Ionson, J. A.

    1981-01-01

    Fast plasma heating by anomalous and inertial resistivity effects is described. A small fraction of the plasma contains strong currents that run parallel to the magnetic field and are driven by an exponentiating electric field. The anomalous character of the current dissipation is caused by the excitation of electrostatic ion cyclotron and/or ion acoustic waves. The role of resistivity due to geometrical effects is considered. Through the use of a marginal stability analysis, equations for the average electron and ion temperatures are derived and numerically solved. The evolution of the plasma is described as a path in the drift velocity diagram, in which the drift velocity is plotted as a function of the electron to ion temperature ratio.

  11. Electric Crosstalk Effect in Valence Change Resistive Random Access Memory

    NASA Astrophysics Data System (ADS)

    Sun, Jing; Wang, Hong; Wu, Shiwei; Song, Fang; Wang, Zhan; Gao, Haixia; Ma, Xiaohua

    2017-08-01

    Electric crosstalk phenomenon in valence change resistive switching memory (VCM) is systematically investigated. When a voltage is applied on the VCM device, an electric field is formed in the isolated region between the devices, which causes the oxygen vacancies in conductive filaments (CFs) to drift apart, leading to a consequent resistance degradation of the neighboring devices. The effects of distance between memory cells, electrodes widths and physical dimensions of CFs on the memory performance are investigated in this work. Furthermore, the strategies to mitigate electric crosstalk effects are developed. According to the simulation results, the crosstalk phenomenon can become more severe as the distance between memory cells or the electrode width decreases. In order to optimize the device performance, it is helpful to control the location of the break points of CFs in the device close to the top electrode. Alternatively, taking the integration density into account, switching materials with a small field accelerated parameter can also contribute to obtaining a stable performance.

  12. [Effect of transgenic insect-resistant rice on biodiversity].

    PubMed

    Zhang, Lei; Zhu, Zhen

    2011-05-01

    Rice is the most important food crops in maintaining food security in China. The loss of China's annual rice production caused by pests is over ten million tons. Present studies showed that the transgenic insect-resistant rice can substantially reduce the application amount of chemical pesticides. In the case of no pesticide use, the pest density in transgenic rice field is significantly lower than that in non-transgenic field, and the neutral insects and natural enemies of pests increased significantly, indicating that the ecological environment and biodiversity toward the positive direction. The gene flow frequency from transgenic rice is dramatically reduced with the distance increases, reaching less than 0.01% at the distance of 6.2 m. Application of transgenic insect-resistant rice in China has an important significance for ensuring food security, maintaining sustainable agricultural development, and protecting the ecological environment and biodiversity. This review summarized the research progress in transgenic insect-resistant rice and its effect on biodiversity. The research directions and development trends of crop pest controlling in future are discussed. These help to promote better use of transgenic insect-resistant rice.

  13. Resistance blow-up effect in micro-circuit engineering

    NASA Astrophysics Data System (ADS)

    Tan, Michael L. P.; Saxena, Tanuj; Arora, Vijay K.

    2010-12-01

    The nonlinearity in the I- V characteristics of a scaled-down micro/nano-scale resistive channel is shown to elevate the DC and signal resistance as current approaches its saturation value. The deviation from traditional circuit engineering takes place when the applied voltage is increased beyond the critical voltage V c = ( V t/ ℓ) L, where V t is the thermal voltage, ℓ is the ohmic mean free path, and L is the length of the conducting channel. This resistance blow-up is more pronounced for a smaller-length resistor in a micro-circuit of two resistors with same ohmic value. The power consumed P = VI not only is lower but also is a linear function of voltage V as compared to the quadratic rise with V in the ohmic regime. The resistance blow-up effect also gives enhanced RC time constant for transients when a digital signal switches from low to high or vice versa. These results are of immense value to circuit designers and those doing device characterization to extract parasitic and transport parameters.

  14. The effect of preexercise carbohydrate status on resistance exercise performance.

    PubMed

    Mitchell, J B; DiLauro, P C; Pizza, F X; Cavender, D L

    1997-09-01

    The purpose of this study was to determine the effect of a high vs. a low preexercise carbohydrate (CHO) diet on performance during multiple sets of resistance exercise. Eleven resistance-trained males performed cycle ergometry to deplete quadriceps muscle glycogen stores, followed by 48 hr of a high (HICHO) or a low (LOCHO) CHO diet. Subjects then performed five sets each of squats, leg presses, and knee extensions (resistance = 15 RM) to failure. Blood samples were taken before and during exercise for determination of glucose and lactate (LA). No differences in performance (repetitions x weight lifted) were observed (HICHO = 15,975 +/- 1,381 and LOCHO = 15,723 +/- 1,231 kg). Blood glucose was significantly higher after exercise for HICHO compared to LOCHO (HICHO = 4.8 +/- 0.2 vs. LOCHO = 3.9 +/- 0.2 mmol.L-1). No differences in LA accumulation were observed. The data indicated that preexercise CHO status did not affect resistance exercise performance. Further, the differences in blood glucose and the similarity in LA responses suggest that glycolysis was maintained in the LOCHO condition, and there may have been an increased reliance on blood glucose when preexercise CHO status was low.

  15. Scale-dependent effects of land cover on water physico-chemistry and diatom-based metrics in a major river system, the Adour-Garonne basin (South Western France).

    PubMed

    Tudesque, Loïc; Tisseuil, Clément; Lek, Sovan

    2014-01-01

    The scale dependence of ecological phenomena remains a central issue in ecology. Particularly in aquatic ecology, the consideration of the accurate spatial scale in assessing the effects of landscape factors on stream condition is critical. In this context, our study aimed at assessing the relationships between multi-spatial scale land cover patterns and a variety of water quality and diatom metrics measured at the stream reach level. This investigation was conducted in a major European river system, the Adour-Garonne river basin, characterized by a wide range of ecological conditions. Redundancy analysis (RDA) and variance partitioning techniques were used to disentangle the different relationships between land cover, water-chemistry and diatom metrics. Our results revealed a top-down "cascade effect" indirectly linking diatom metrics to land cover patterns through water physico-chemistry, which occurred at the largest spatial scales. In general, the strength of the relationships between land cover, physico-chemistry, and diatoms was shown to increase with the spatial scale, from the local to the basin scale, emphasizing the importance of continuous processes of accumulation throughout the river gradient. Unexpectedly, we established that the influence of land cover on the diatom metric was of primary importance both at the basin and local scale, as a result of discontinuous but not necessarily antagonist processes. The most detailed spatial grain of the Corine land cover classification appeared as the most relevant spatial grain to relate land cover to water chemistry and diatoms. Our findings provide suitable information to improve the implementation of effective diatom-based monitoring programs, especially within the scope of the European Water Framework Directive. © 2013 Elsevier B.V. All rights reserved.

  16. Cervical Resistance Training: Effects on Isometric and Dynamic Strength

    DTIC Science & Technology

    2006-11-01

    skinfold thicknesses . San Diego, CA: Naval Health Research Center; 1984. Report No: 84–39. 3. Coakwell MR, Bloswick DS, Moser R Jr. High-risk head and...Strength, Dynamic Strength, and Neck Circumference Isometric strength values are displayed in Table I. For isometric strength-flexion, the 2 2 ANOVA...Also, a main effect was observed TABLE I. RESISTANCE TRAINING VS. CONTROL GROUPS: ISOMETRIC STRENGTH (LB). RT Group (n 5) C Group (n 5) FLX EXT

  17. The Long Ordeal: The Metric Changeover in the U.S.

    ERIC Educational Resources Information Center

    Zupko, Ronald Edward

    1976-01-01

    The United States has the distinction of being the last industrial nation to adopt the metric system of measurement. Presents the principal personalities and governmental programs involved in this two-century struggle and the major reasons behind this country's long-standing and, oftentimes, bitter resistance to metrication. (Author/RK)

  18. Effect and Safety of Shihogyejitang for Drug Resistant Childhood Epilepsy

    PubMed Central

    Lee, Jinsoo; Son, Kwanghyun; Hwang, Gwiseo

    2016-01-01

    Objective. Herbal medicine has been widely used to treat drug resistant epilepsy. Shihogyejitang (SGT) has been commonly used to treat epilepsy. We investigated the effect and safety of SGT in children with drug resistant epilepsy. Design. We reviewed medical records of 54 patients with epilepsy, who failed to respond to at least two antiepileptic drugs and have been treated with SGT between April 2006 and June 2014 at the Department of Pediatric Neurology, I-Tomato Hospital, Korea. Effect was measured by the response rate, seizure-free rate, and retention rate at six months. We also checked adverse events, change in antiepileptic drugs use, and the variables related to the outcome. Results. Intent-to-treat analysis showed that, after six months, 44.4% showed a >50% seizure reduction, 24.1% including seizure-free, respectively, and 53.7% remained on SGT. Two adverse events were reported, mild skin rash and fever. Focal seizure type presented significantly more positive responses when compared with other seizure types at six months (p = 0.0284, Fisher's exact test). Conclusion. SGT is an effective treatment with excellent tolerability for drug resistant epilepsy patients. Our data provide evidence that SGT may be used as alternative treatment option when antiepileptic drug does not work in epilepsy children. PMID:27047568

  19. Metric conversion: Future progress depends upon private sector and public support. Report to Congressional requesters

    NASA Astrophysics Data System (ADS)

    1994-01-01

    In reviewing federal metric conversion (metrication) activities, the General Accounting Office (GAO) evaluated federal agency activities in (1) establishing metric guidelines and preparing reports on the transition, (2) using the metric system in procurements, (3) using the metric system in grants and other business activities, and (4) dealing with private sector and public attitudes toward conversion. Since 1990, federal preparations for metric conversion have advanced dramatically, with more than 30 agencies having developed some combination of guidelines, transition plans, and progress reports that indicate a substantially greater commitment to metrication. However, they are still facing serious difficulties in putting their plans into practice. These difficulties include a procurement environment in which most products are nonmetric and in which federal agencies represent too small a share of the total market to stimulate private sector conversion. Mixed progress has been made toward metric conversion in the areas of federal grants and other business activities. Grants for research require the use of the metric system, but such a commitment has not been made for grants in other areas, such as housing and education. Agencies that undertake other business-related activities, such as federal programs involving farmers or highway signs, are concerned about private sector and public resistance to conversion. Now that most agencies have made significant progress in preparing for metric conversion, a broader national dialogue between the government, the private sector, and the public is needed to discuss the next steps in decision-making about metric conversion.

  20. Finite element analysis of the effect of electrode resistivity on resistivity measurement in a diamond anvil cell

    NASA Astrophysics Data System (ADS)

    Huang, Xiaowei; Gao, Chunxiao; Zhang, Dongmei; Li, Ming; He, Chunyuan; Hao, Aimin; Yu, Cuiling; Sang, Chong; Liu, Cailong; Wang, Yue; Guan, Rui; Li, Dongmei; Zou, Guangtian; Ma, Yanzhang

    2007-05-01

    The effect of electrode resistivity on the in situ resistivity measurement in a diamond anvil cell was studied using finite element analysis. The theoretical analysis reveals that the origin of significant error for a thin sample is mainly caused by the resistivity difference between the electrodes and the sample. The authors found that reducing such resistivity differences can improve the accuracy. The result shows that the van der Pauw method [L. J. van der Pauw, Philips Tech. Rev. 20, 220 (1958)] can provide more accurate results for thin samples compared with the four-point probe method. This approach provides means to simulate actual experiments and to eliminate the measurement error.

  1. The correlation of metrics in complex networks with applications in functional brain networks

    NASA Astrophysics Data System (ADS)

    Li, C.; Wang, H.; de Haan, W.; Stam, C. J.; Van Mieghem, P.

    2011-11-01

    An increasing number of network metrics have been applied in network analysis. If metric relations were known better, we could more effectively characterize networks by a small set of metrics to discover the association between network properties/metrics and network functioning. In this paper, we investigate the linear correlation coefficients between widely studied network metrics in three network models (Bárabasi-Albert graphs, Erdös-Rényi random graphs and Watts-Strogatz small-world graphs) as well as in functional brain networks of healthy subjects. The metric correlations, which we have observed and theoretically explained, motivate us to propose a small representative set of metrics by including only one metric from each subset of mutually strongly dependent metrics. The following contributions are considered important. (a) A network with a given degree distribution can indeed be characterized by a small representative set of metrics. (b) Unweighted networks, which are obtained from weighted functional brain networks with a fixed threshold, and Erdös-Rényi random graphs follow a similar degree distribution. Moreover, their metric correlations and the resultant representative metrics are similar as well. This verifies the influence of degree distribution on metric correlations. (c) Most metric correlations can be explained analytically. (d) Interestingly, the most studied metrics so far, the average shortest path length and the clustering coefficient, are strongly correlated and, thus, redundant. Whereas spectral metrics, though only studied recently in the context of complex networks, seem to be essential in network characterizations. This representative set of metrics tends to both sufficiently and effectively characterize networks with a given degree distribution. In the study of a specific network, however, we have to at least consider the representative set so that important network properties will not be neglected.

  2. Shaping Effects on Resistive-Plasma Resistive-Wall Mode Stability in a Tokamak

    NASA Astrophysics Data System (ADS)

    Rhodes, Dov; Cole, A. J.; Navratil, G. A.; Levesque, J. P.; Mauel, M. E.; Brennan, D. P.; Finn, J. M.; Fitzpatrick, R.

    2016-10-01

    A sharp-boundary MHD model is used to explore the effects of toroidal curvature and cross-sectional shaping on resistive-plasma resistive-wall modes in a tokamak. Building on the work of Fitzpatrick, we investigate mode stability with fixed toroidal number n =1 and a broad spectrum of poloidal m-numbers, given varying aspect-ratio, elongation, triangularity and up-down asymmetry. The speed and versatility of the sharp-boundary model facilitate exploration of a large parameter space, revealing qualitative trends to be further investigated by larger codes. In addition, the study addresses the effect of geometric mode-coupling on higher beta stability limits associated with an ideal-plasma or ideal-wall. These beta limits were used by Brennan and Finn to identify plasma response domains for feedback control. Present results show how geometric mode-coupling affects the stability limits and plasma response domains. The results are explained by an analytic reduced-MHD model with two coupled modes having different m-numbers. The next phase of this work will explore feedback control in different tokamak geometries. Supported by U.S. DOE Grant DE-FG02-86ER53222.

  3. The Effects of Bowel Preparation on Microbiota-Related Metrics Differ in Health and in Inflammatory Bowel Disease and for the Mucosal and Luminal Microbiota Compartments

    PubMed Central

    Shobar, Rima M; Velineni, Suresh; Keshavarzian, Ali; Swanson, Garth; DeMeo, Mark T; Melson, Joshua E; Losurdo, John; Engen, Philip A; Sun, Yan; Koenig, Lars; Mutlu, Ece A

    2016-01-01

    OBJECTIVES: Bowel preparations (BPs) taken before colonoscopy may introduce a confounding effect on the results of gastrointestinal microbiota studies. This study aimed to determine the effect of bowel preparation on the mucosa-associated and luminal colonic microbiota in healthy subjects (HC) and inflammatory bowel disease (IBD) patients. METHODS: Biopsy samples (n=36) and fecal samples (n=30) were collected from 10 HC and 8 IBD subjects pre- and post-BP. 16S rRNA gene was pyrosequenced using 454 Titanium protocols. We compared the differences between the pre- and post-BP samples (i.e., comparisons-across-bowel-prep); we examined the effect of BP on the expected separation of the mucosal vs. the luminal compartments (i.e., comparisons-across-compartments). Last, we compared the baseline differences between the HC vs. IBD groups (a secondary analysis), and examined whether the differences between the HC vs. IBD changed after BP. RESULTS: In comparisons-across-bowel-prep, the Shannon's index (SI) decreased only in the biopsy samples of IBD subjects post-BP (P=0.025) and phylogenetic diversity-whole tree (PD-WT) metric decreased in biopsy samples of HC subjects post-BP (P=0.021). In secondary comparisons, the subtle differences between the fecal samples of the HC vs. IBD groups, in terms of evenness and the SI, were not apparent post-BP. In terms of β-diversity, in comparisons-across-bowel-prep, the proportion of shared operational taxonomic units (OTUs) in pre- and post-BP samples was low (~30%) and unweighted Unifrac distances between pre- and post-BP specimens ranged from 0.52 to 0.66. HC biopsies were affected more than IBD biopsies with BP (P=0.004). In comparisons-across-compartments, the proportion of shared OTUs between biopsy and fecal samples increased and Unifrac distances decreased post-BP in IBD subjects, reducing the differences between the mucosal and luminal compartments of the gut microbiota. Interindividual differences in Unifrac distances were

  4. The Effects of Bowel Preparation on Microbiota-Related Metrics Differ in Health and in Inflammatory Bowel Disease and for the Mucosal and Luminal Microbiota Compartments.

    PubMed

    Shobar, Rima M; Velineni, Suresh; Keshavarzian, Ali; Swanson, Garth; DeMeo, Mark T; Melson, Joshua E; Losurdo, John; Engen, Philip A; Sun, Yan; Koenig, Lars; Mutlu, Ece A

    2016-02-11

    Bowel preparations (BPs) taken before colonoscopy may introduce a confounding effect on the results of gastrointestinal microbiota studies. This study aimed to determine the effect of bowel preparation on the mucosa-associated and luminal colonic microbiota in healthy subjects (HC) and inflammatory bowel disease (IBD) patients. Biopsy samples (n=36) and fecal samples (n=30) were collected from 10 HC and 8 IBD subjects pre- and post-BP. 16S rRNA gene was pyrosequenced using 454 Titanium protocols. We compared the differences between the pre- and post-BP samples (i.e., comparisons-across-bowel-prep); we examined the effect of BP on the expected separation of the mucosal vs. the luminal compartments (i.e., comparisons-across-compartments). Last, we compared the baseline differences between the HC vs. IBD groups (a secondary analysis), and examined whether the differences between the HC vs. IBD changed after BP. In comparisons-across-bowel-prep, the Shannon's index (SI) decreased only in the biopsy samples of IBD subjects post-BP (P=0.025) and phylogenetic diversity-whole tree (PD-WT) metric decreased in biopsy samples of HC subjects post-BP (P=0.021). In secondary comparisons, the subtle differences between the fecal samples of the HC vs. IBD groups, in terms of evenness and the SI, were not apparent post-BP. In terms of β-diversity, in comparisons-across-bowel-prep, the proportion of shared operational taxonomic units (OTUs) in pre- and post-BP samples was low (~30%) and unweighted Unifrac distances between pre- and post-BP specimens ranged from 0.52 to 0.66. HC biopsies were affected more than IBD biopsies with BP (P=0.004). In comparisons-across-compartments, the proportion of shared OTUs between biopsy and fecal samples increased and Unifrac distances decreased post-BP in IBD subjects, reducing the differences between the mucosal and luminal compartments of the gut microbiota. Interindividual differences in Unifrac distances were preserved even with BP effects

  5. Repeated bout effect is absent in resistance trained men

    PubMed Central

    Falvo, Michael J.; Schilling, Brian K.; Bloomer, Richard J.; Smith, Webb A.

    2009-01-01

    A prior bout of exercise is well known to confer protection from subsequent eccentric bouts (i.e. repeated bout effect; RBE), which may be fostered through neural adaptations, specifically a shift in the frequency content of the surface electromyogram (EMG). It is currently not clear whether chronically resistance trained men are capable of a RBE driven by neural adaptations. Eleven resistance trained men (23.5 ± 3.4 yrs) performed 100 eccentric actions of the barbell bench press exercise, followed by an equivalent bout 14 days later. Indirect markers of muscle damage (i.e. force production, soreness) along with surface EMG were measured before and through 48 h of recovery. Median frequency and maximal isometric force demonstrated time main effects (p > 0.05), but no RBE. A prior bout of eccentric exercise does not confer a RBE for indirect markers of muscle injury or elicit changes in the frequency content of the EMG signal in resistance trained men. PMID:19059793

  6. Edge effect in ohmic contacts on high-resistivity semiconductors

    NASA Astrophysics Data System (ADS)

    Ruzin, Arie

    2016-01-01

    Current increase due to edge effect in ohmic contacts was calculated by finite-element software in three-dimensional devices. The emphasis in this study is on semi-intrinsic (SI) and compensated high resistivity semiconductors. It was found that the enhanced electric field around the contact edges may cause about twofold increase in the total contact current. For contact radii larger than the device thickness and nano scale contacts the impact is considerably reduced. In nanoscale contacts the edge effect does not control the electric field under the entire contact, but rather decreases. The introduction of velocity saturation model has a limited impact, and only in compensated semiconductors.

  7. Chemically amplified resist using self-solubility acceleration effect

    NASA Astrophysics Data System (ADS)

    Kihara, Naoko; Ushirogouchi, Tohru; Tada, Tsukasa; Naito, Takuya; Saito, Satoshi; Nakase, Makoto

    1994-11-01

    This paper concerns a novel three-component chemically amplified positive tone resist system for EB lithography composed of a novolak resin, an acid generator, and a newly synthesized dissolution inhibitor. To obtain resist materials with high sensitivity and high contrast, the authors synthesized four 1-(3H)-isobenzofuranone derivatives as novel dissolution inhibitors, which contain a tert-butoxycarbonyl (t-Boc) group and a lactone ring. The t-Boc group of these dissolution inhibitors was effectively decomposed by an acid catalyzed thermal reaction. In addition to this decomposition, the lactone ring of the decomposed product was spontaneously cleft in an aqueous base to generate carboxylic acid. Among these synthesized substances, only the t-Boc derivative of o-cresolphthalein, named CP-TBOC, showed an excellent solubility in 1-acetoxy-2-ethoxyethane. The subsequent cleavage in an aqueous developer was investigated by UV-visible spectroscopy.

  8. The effect of ceramic/metal gradient armor's components characteristic on its impact-resistant characteristic

    SciTech Connect

    Liu Lisheng; Zhang Qingjie; Zhai Pengcheng; Cao Dongfeng

    2008-02-15

    The effect of ceramic/metal gradient armor's components characteristic on its impact-resistant characteristic has been investigated by a new modified Alekseevskii-Tate equation. The following researching work is done by the former model [1]: the effect of ceramic layer on the impact-resistant characteristic, the effect of gradient layer on the impact-resistant characteristic and the effect of metal layer on the impact-resistant characteristic.

  9. Non-metric chaotic inflation

    SciTech Connect

    Enqvist, Kari; Koivisto, Tomi; Rigopoulos, Gerasimos E-mail: T.S.Koivisto@astro.uio.no

    2012-05-01

    We consider inflation within the context of what is arguably the simplest non-metric extension of Einstein gravity. There non-metricity is described by a single graviscalar field with a non-minimal kinetic coupling to the inflaton field Ψ, parameterized by a single parameter γ. There is a simple equivalent description in terms of a massless field and an inflaton with a modified potential. We discuss the implications of non-metricity for chaotic inflation and find that it significantly alters the inflaton dynamics for field values Ψ∼>M{sub P}/γ, dramatically changing the qualitative behaviour in this regime. In the equivalent single-field description this is described as a cuspy potential that forms of barrier beyond which the inflation becomes a ghost field. This imposes an upper bound on the possible number of e-folds. For the simplest chaotic inflation models, the spectral index and the tensor-to-scalar ratio receive small corrections dependent on the non-metricity parameter. We also argue that significant post-inflationary non-metricity may be generated.

  10. Metrics for Occupations. Information Series No. 118.

    ERIC Educational Resources Information Center

    Peterson, John C.

    The metric system is discussed in this information analysis paper with regard to its history, a rationale for the United States' adoption of the metric system, a brief overview of the basic units of the metric system, examples of how the metric system will be used in different occupations, and recommendations for research and development. The…

  11. Metrical segmentation in Dutch: vowel quality or stress?

    PubMed

    Quené, H; Koster, M L

    1998-01-01

    Previous experiments using a word-spotting task suggest that English listeners use metrically strong syllables to segment continuous speech into discrete words (Cutler & Norris, 1988). The present study is concerned with this metrical segmentation strategy in Dutch. Although Dutch and English share general metrical properties, they differ in ways that may affect segmentation. First, the acoustic cues for metrically strong syllables are less salient in Dutch than in English; hence a metrical segmentation strategy is less likely to be applied by Dutch listeners. Second, vowel quality depends less on metrical structure in Dutch than in English; hence segmentation in Dutch is presumably triggered by other acoustic cues, namely, those related to stress. Experiment 1 shows that stress strongly affects Dutch listeners' ability and speed in spotting Dutch monosyllabic words in disyllabic nonwords. Experiment 2, however, finds the same stress effect when only the target words are presented, without a subsequent syllable triggering segmentation. A third experiment shows a small effect of vowel quality on error scores, but not on latencies. These results suggest that Dutch listeners do not apply a metrical segmentation strategy. The discrepancy between the two languages suggests that segmentation strategies may depend on language-specific regularities in the phonology and in the lexicon.

  12. The effect of rifaximin on gut flora and Staphylococcus resistance.

    PubMed

    Kim, Mi-Sung; Morales, Walter; Hani, Andres Ardila; Kim, Sharon; Kim, Gene; Weitsman, Stacy; Chang, Christopher; Pimentel, Mark

    2013-06-01

    Rifaximin is a non-absorbed antibiotic relative of rifampicin. The location of effect and staphylococcal resistance are two recent potential concerns with rifaximin. In this study we evaluate the location of effect of rifaximin as well as the development of staphylococcal rifampicin resistance. Rats were divided into three groups. Group 1 gavaged for 10 days with PBS, group 2 gavaged with rifaximin for 10 days, and group 3 gavaged with rifaximin for 10 days and housed for 30 days. In each group, stool was collected daily for quantitative culture of Staphylococcus spp. and coliforms. After euthanasia luminal bacterial counts were determined at multiple gut locations by qPCR. Rifampicin susceptibility was tested on Staphylococcus pre and post rifaximin. At baseline, rats had a median of 2.90 × 10(6) cfu/ml Staphylococcus spp. in stool. After 10 days of rifaximin, this dropped to 1.20 × 10(5) cfu/ml (P < 0.01). With coliform counts, rats had a median of 1.86 × 10(4) cfu/ml at baseline which dropped to 2.2 × 10(3) cfu/ml (P < 0.01) after rifaximin. After cessation of rifaximin, coliform counts recovered within 3 days. When examining the total bacterial counts by qPCR, rifaximin reduced small bowel bacterial levels, but not colon. This reduction was sustained for 30 days. No colonies of Staphylococcus became resistant and only one colony was intermediate. The mean inhibitory concentration for rifampicin was not different before and after rifaximin. Staphylococcal spp. fail to demonstrate resistance to rifampicin after rifaximin. The transient reductions in stool coliform counts recover while rifaximin appears to produce durable reductions in duodenal bacteria.

  13. Perpetuating Effects of Androgen Deficiency on Insulin-resistance

    PubMed Central

    Cameron, Judy L.; Jain, Ruhee; Rais, Maham; White, Ashley E.; Beer, Tomasz M.; Kievit, Paul; Winters-Stone, Kerri; Messaoudi, Ilhem; Varlamov, Oleg

    2016-01-01

    Background/Objectives Androgen deprivation therapy (ADT) is commonly used for treatment of prostate cancer, but is associated with side effects such as sarcopenia and insulin resistance. The role of lifestyle factors such as diet and exercise on insulin sensitivity and body composition in testosterone-deficient males is poorly understood. The aim of the present study was to examine the relationships between androgen status, diet, and insulin sensitivity. Subjects/Methods Middle-aged (11–12-yo) intact and orchidectomized male rhesus macaques were maintained for two months on a standard chow diet, and then exposed for six months to a Western-style, high-fat/calorie-dense diet (WSD) followed by four months of caloric restriction (CR). Body composition, insulin sensitivity, physical activity, serum cytokine levels, and adipose biopsies were evaluated before and after each dietary intervention. Results Both intact and orchidectomized animals gained similar proportions of body fat, developed visceral and subcutaneous adipocyte hypertrophy, and became insulin resistant in response to the WSD. CR reduced body fat in both groups, but reversed insulin resistance only in intact animals. Orchidectomized animals displayed progressive sarcopenia, which persisted after the switch to CR. Androgen deficiency was associated with increased levels of interleukin-6 and macrophage-derived chemokine (CCL22), both of which were elevated during CR. Physical activity levels showed a negative correlation with body fat and insulin sensitivity. Conclusion Androgen deficiency exacerbated the negative metabolic side effects of the WSD, such that CR alone was not sufficient to improve altered insulin sensitivity, suggesting that ADT patients will require additional interventions to reverse insulin resistance and sarcopenia. PMID:27534842

  14. Identifying influential metrics in the combined metrics approach of fault prediction.

    PubMed

    Goyal, Rinkaj; Chandra, Pravin; Singh, Yogesh

    2013-01-01

    Fault prediction is a pre-eminent area of empirical software engineering which has witnessed a huge surge over the last couple of decades. In the development of a fault prediction model, combination of metrics results in better explanatory power of the model. Since the metrics used in combination are often correlated, and do not have an additive effect, the impact of a metric on another i.e. interaction should be taken into account. The effect of interaction in developing regression based fault prediction models is uncommon in software engineering; however two terms and three term interactions are analyzed in detail in social and behavioral sciences. Beyond three terms interactions are scarce, because interaction effects at such a high level are difficult to interpret. From our earlier findings (Softw Qual Prof 15(3):15-23) we statistically establish the pertinence of considering the interaction between metrics resulting in a considerable improvement in the explanatory power of the corresponding predictive model. However, in the aforesaid approach, the number of variables involved in fault prediction also shows a simultaneous increment with interaction. Furthermore, the interacting variables do not contribute equally to the prediction capability of the model. This study contributes towards the development of an efficient predictive model involving interaction among predictive variables with a reduced set of influential terms, obtained by applying stepwise regression.

  15. A parallel variable metric optimization algorithm

    NASA Technical Reports Server (NTRS)

    Straeter, T. A.

    1973-01-01

    An algorithm, designed to exploit the parallel computing or vector streaming (pipeline) capabilities of computers is presented. When p is the degree of parallelism, then one cycle of the parallel variable metric algorithm is defined as follows: first, the function and its gradient are computed in parallel at p different values of the independent variable; then the metric is modified by p rank-one corrections; and finally, a single univariant minimization is carried out in the Newton-like direction. Several properties of this algorithm are established. The convergence of the iterates to the solution is proved for a quadratic functional on a real separable Hilbert space. For a finite-dimensional space the convergence is in one cycle when p equals the dimension of the space. Results of numerical experiments indicate that the new algorithm will exploit parallel or pipeline computing capabilities to effect faster convergence than serial techniques.

  16. Obtaining the metric of our Universe

    NASA Astrophysics Data System (ADS)

    Jacobs, Mark W.; Linder, Eric V.; Wagoner, Robert V.

    1992-05-01

    We formulate a method for solving the gravitational field equations for perturbations to a Friedmann-Robertson-Walker metric, which does not depend on any kind of averaging procedure or make any a priori assumptions about the magnitude of fluctuations in the matter variables. We present a Green's function for obtaining the effective potential which characterizes the metric perturbations directly from the (possibly large) density fluctuations, and describe the application to astrophysical observations, for example, the angular-diameter distance-versus-redshift relation. The results do not assume a particular model for the formation of structure in the matter distribution, and are valid everywhere in our Universe outside of strong-field regions (e.g., black holes).

  17. Population metrics for suicide events: A causal inference approach.

    PubMed

    He, Hua; Lu, Naiji; Stephens, Brady; Xia, Yinglin; Bossarte, Robert M; Kane, Cathleen P; Tang, Wan; Tu, Xin M

    2017-01-01

    Large-scale public health prevention initiatives and interventions are a very important component to current public health strategies. But evaluating effects of such large-scale prevention/intervention faces a lot of challenges due to confounding effects and heterogeneity of study population. In this paper, we will develop metrics to assess the risk for suicide events based on causal inference framework when the study population is heterogeneous. The proposed metrics deal with the confounding effect by first estimating the risk of suicide events within each of the risk levels, number of prior attempts, and then taking a weighted sum of the conditional probabilities. The metrics provide unbiased estimates of the risk of suicide events. Simulation studies and a real data example will be used to demonstrate the proposed metrics.

  18. Distribution Metrics and Image Segmentation

    PubMed Central

    Georgiou, Tryphon; Michailovich, Oleg; Rathi, Yogesh; Malcolm, James; Tannenbaum, Allen

    2007-01-01

    The purpose of this paper is to describe certain alternative metrics for quantifying distances between distributions, and to explain their use and relevance in visual tracking. Besides the theoretical interest, such metrics may be used to design filters for image segmentation, that is for solving the key visual task of separating an object from the background in an image. The segmenting curve is represented as the zero level set of a signed distance function. Most existing methods in the geometric active contour framework perform segmentation by maximizing the separation of intensity moments between the interior and the exterior of an evolving contour. Here one can use the given distributional metric to determine a flow which minimizes changes in the distribution inside and outside the curve. PMID:18769529

  19. Statistical estimation of ozone exposure metrics

    NASA Astrophysics Data System (ADS)

    Blankenship, Erin E.; Stefanski, L. A.

    Data from recent experiments at North Carolina State University and other locations provide a unique opportunity to study the effect of ambient ozone on the growth of clover. The data consist of hourly ozone measurements over a 140 day growing season at eight sites in the US, coupled with clover growth response data measured every 28 days. The objective is to model an indicator of clover growth as a function of ozone exposure. A common strategy for dealing with the numerous hourly ozone measurements is to reduce these to a single summary measurement, a so-called exposure metric, for the growth period of interest. However, the mean ozone value is not necessarily the best summarization, as it is widely believed that low levels of ozone have a negligible effect on growth, whereas peak ozone values are deleterious to plant growth. There are also suspected interactions with available sunlight, temperature and humidity. A number of exposure metrics have been proposed that reflect these beliefs by assigning different weights to ozone values according to magnitude, time of day, temperature and humidity. These weighting schemes generally depend on parameters that have, to date, been subjectively determined. We propose a statistical approach based on profile likelihoods to estimate the parameters in these exposure metrics.

  20. Experimental validation of navigation workload metrics

    SciTech Connect

    Schryver, J.C.; Wachtel, J.A.

    1994-04-01

    Advanced digital computer display interfaces in the control room may increase operator workload. Workstation monitors provide limited display area, and information is represented in large-scale display networks. Display navigation may generate disorienting effects, require additional resources for window management, and increase memory and data integration requirements. Six ORNL employees participated in an experiment to validate proposed metrics of navigation workload in the advanced control room. The task environment was a display network consisting of 25 windows resembling a simplified Safety Parameter Display System for Pressurized Water Reactors. A repeated measures design with 3 within subjects factors was employed. The factors were task difficulty, navigation distance level, and a blocking factor. Participants were asked to monitor a single parameter or two parameters. Fourteen candidate metrics were tested. Analysis of variance of the modified task load index (MTLX) and rating subscales demonstrated substantial support for the claim that navigation of large-scale display networks can impose additional mental load. Primary and secondary task performance measures exhibited ceiling effects. Memory probes for these tasks were inadequate because they were recognition-based and coarse. Eye gaze measures were not validated, indicating a need for more refined data reduction algorithms. Strong positive correlations were found between MTLX and both navigation duration and standard deviation of pupil diameter. Further study and increased statistical power are required to validate objective navigation workload metrics.

  1. On the Kähler metrics over Symd(X)

    NASA Astrophysics Data System (ADS)

    Aryasomayajula, Anilatmaja; Biswas, Indranil; Morye, Archana S.; Sengupta, Tathagata

    2016-12-01

    Let X be a compact connected Riemann surface of genus g, with g ≥ 2. For each d < η(X) , where η(X) is the gonality of X, the symmetric product Symd(X) embeds into Picd(X) by sending an effective divisor of degree d to the corresponding holomorphic line bundle. Therefore, the restriction of the flat Kähler metric on Picd(X) is a Kähler metric on Symd(X) . We investigate this Kähler metric on Symd(X) . In particular, we estimate it is Bergman kernel. We also prove that any holomorphic automorphism of Symd(X) is an isometry.

  2. DLA Energy Biofuel Feedstock Metrics Study

    DTIC Science & Technology

    2012-12-11

    moderately/highly in- vasive  Metric 2: Genetically modified organism ( GMO ) hazard, Yes/No and Hazard Category  Metric 3: Species hybridization...4– biofuel distribution Stage # 5– biofuel use Metric 1: State inva- siveness ranking Yes Minimal Minimal No No Metric 2: GMO hazard Yes...may utilize GMO microbial or microalgae species across the applicable biofuel life cycles (stages 1–3). The following consequence Metrics 4–6 then

  3. Kerr-Schild–Kundt metrics are universal

    NASA Astrophysics Data System (ADS)

    Gürses, Metin; Çağrı Şişman, Tahsin; Tekin, Bayram

    2017-04-01

    We define (non-Einsteinian) universal metrics as the metrics that solve the source-free covariant field equations of generic gravity theories. Here, extending the rather scarce family of universal metrics known in the literature, we show that the Kerr-Schild–Kundt class of metrics are universal. Besides being interesting on their own, these metrics can provide consistent backgrounds for quantum field theory at extremely high energies.

  4. To Resist or Not to Resist? The Effect of Context and Crime Characteristics on Sex Offenders' Reaction to Victim Resistance

    ERIC Educational Resources Information Center

    Balemba, Samantha; Beauregard, Eric; Mieczkowski, Tom

    2012-01-01

    Circumstances under which a sexual assault takes place and how these circumstances affect offenders' reactions to victim resistance are not well understood. Previous studies have not thoroughly examined the interactions that take place between situational factors and resistance. Using a combination of logistic regression and Chi-square Automatic…

  5. To Resist or Not to Resist? The Effect of Context and Crime Characteristics on Sex Offenders' Reaction to Victim Resistance

    ERIC Educational Resources Information Center

    Balemba, Samantha; Beauregard, Eric; Mieczkowski, Tom

    2012-01-01

    Circumstances under which a sexual assault takes place and how these circumstances affect offenders' reactions to victim resistance are not well understood. Previous studies have not thoroughly examined the interactions that take place between situational factors and resistance. Using a combination of logistic regression and Chi-square Automatic…

  6. Reliability of in-stream retention metrics

    NASA Astrophysics Data System (ADS)

    Savickis, Jevgenijs; Zaramella, Mattia; Marion, Andrea

    2016-04-01

    The temporary solute retention within transient storage zones (TSZs) has been shown to have a large effect on the transport of solute. This retention can significantly increase the overall in-stream residence time and as consequence increase the contact time of solute with aquatic interfaces (biota, sediment) and living species. An important question that arises is whether the currently available metrics adequately represent retention mechanism. This work attempts to investigate the reliability of two existing measures, the hydrological retention factor (Rh) and the fraction of median travel time due to transient storage zone (Fmed200). For this purpose, five conservative tracer tests were conducted in four European streams with distinct morphological, sediment composition, vegetation and hydraulic characteristics. The obtained breakthrough curves (BTCs) were used to derive storage zone parameters (storage zone area, storage zone exchange coefficient and mean residence time), which then were used for comparison and in the metric expressions. The storage zone parameters were computed using a single TSZ model OTIS-P and a multiple TSZ model STIR. The STIR model was applied to BTCs as an additional tool to separate TSZs into short timescale (ST) and long timescale (LT). The study results reveal correlation between Fmed200 and LT residence time T2 values, where the streams with the lowest Fmed200 (0.01-0.96) have the smallest long timescale storage zones T2 values, ranging from 912 s to 1402 s. The findings also demonstrate an influence of discharge rate on both retention metrics. The greatest Fmed200 (6.19) and Rh (0.938) values are calculated for the streams with low discharge rates (0.08-0.10 m3s-1) and a relatively high ST storage zone residence times T1 (159 s to 351 s). Results show that the Fmed200 and Rh metrics are strongly affected by the short timescale transient storage zones, whereas the LT storage zones (hyporheic) effects are not taken into account.

  7. The effects of high resistance-few repetitions and low resistance-high repetitions resistance training on climbing performance.

    PubMed

    Hermans, Espen; Andersen, Vidar; Saeterbakken, Atle Hole

    2017-05-01

    The aim of the study was to compare the effects of different strength training intensities on climbing performance, climbing-specific tests and a general strength test. Thirty lower grade and intermediate-level climbers participated in a 10-week training programme. The participants were randomized into three groups: high resistance-few repetitions training groups (HR-FR), low resistance-high repetitions training groups (LR-HR) and a control group (CON) which continued climbing/training as usual. Post-testing results demonstrated statistical tendencies for climbing performance improvements in the HR-FR and LR-HR (p = 0.088-0.090, effect size = 0.55-0.73), but no differences were observed between the groups (p = 0.950). For the climbing-specific tests, no differences were observed between the groups (p = 0.507-1.000), but the HR-FR and LR-HR improved their time in both Dead-hang (p = 0.004-0.026) and Bent-arm hang (p < 0.001-0.002). The HR-FR and LR-HR improved their 12RM strength in pull-down (p ≤ 0.001), but not the CON group (p = 0.250). No differences were observed in the CON group in any of the tests (p = 0.190-0.596) with the exception of improvement in Bent-arm Hang (p = 0.018). The training groups reduced their climbing sessions during the intervention compared to the CON group (p = 0.057-0.074). In conclusion, HR-FR and LR-HR training programmes demonstrated an 11% and 12% non-significant improvement in climbing performance despite a 50% reduction in climbing sessions, but improved the results in strength and climbing-specific tests. None of the training intensities was superior compared to the others.

  8. Chaos-based wireless communication resisting multipath effects

    NASA Astrophysics Data System (ADS)

    Yao, Jun-Liang; Li, Chen; Ren, Hai-Peng; Grebogi, Celso

    2017-09-01

    In additive white Gaussian noise channel, chaos has been shown to be the optimal coherent communication waveform in the sense of using a very simple matched filter to maximize the signal-to-noise ratio. Recently, Lyapunov exponent spectrum of the chaotic signals after being transmitted through a wireless channel has been shown to be unaltered, paving the way for wireless communication using chaos. In wireless communication systems, inter-symbol interference caused by multipath propagation is one of the main obstacles to achieve high bit transmission rate and low bit-error rate (BER). How to resist the multipath effect is a fundamental problem in a chaos-based wireless communication system (CWCS). In this paper, a CWCS is built to transmit chaotic signals generated by a hybrid dynamical system and then to filter the received signals by using the corresponding matched filter to decrease the noise effect and to detect the binary information. We find that the multipath effect can be effectively resisted by regrouping the return map of the received signal and by setting the corresponding threshold based on the available information. We show that the optimal threshold is a function of the channel parameters and of the information symbols. Practically, the channel parameters are time-variant, and the future information symbols are unavailable. In this case, a suboptimal threshold is proposed, and the BER using the suboptimal threshold is derived analytically. Simulation results show that the CWCS achieves a remarkable competitive performance even under inaccurate channel parameters.

  9. Comparing the effects of two distinct eccentric modalities to traditional resistance training in resistance trained, higher functioning older adults.

    PubMed

    Gluchowski, Ashley; Dulson, Deborah; Merien, Fabrice; Plank, Lindsay; Harris, Nigel

    2017-11-01

    The effects of eccentric resistance exercise are of interest in the older adult cohort, but to our knowledge, there is no research on the relative effects of different eccentric modalities on a range of outcomes in higher functioning, resistance trained older adults. 33 resistance-trained older adults (aged 67±4.5years) were randomized into one of three supervised training groups: traditional (TRE), eccentric only (ERE) or eccentrically biased resistance exercise (EBRE) on a 45°, plate-loaded leg press machine. Participants trained twice per week with maximal strength, functional capacity, body composition and blood biomarkers measured before and after the eight-week intervention. Both eccentric and concentric strength, and important functional tasks for independent living significantly improved independent of group. Body composition and blood biomarkers were found to significantly improve in the EBRE group only however, no statistical differences were found between groups. Compared to traditional resistance training, the two eccentric modalities investigated here were equally effective for improvements in maximum muscular strength, functional capacity, body composition and metabolic biomarkers. When training the resistance trained older adult, very heavy isoinertial external loads (at least 70% of one repetition maximum) are effective irrespective of contraction mode. With heavy strength training, resistance trained older adults can continue to expect improvements in health and function. Copyright © 2017 Elsevier Inc. All rights reserved.

  10. Enhanced oxidation resistance of active nanostructures via dynamic size effect

    PubMed Central

    Liu, Yun; Yang, Fan; Zhang, Yi; Xiao, Jianping; Yu, Liang; Liu, Qingfei; Ning, Yanxiao; Zhou, Zhiwen; Chen, Hao; Huang, Wugen; Liu, Ping; Bao, Xinhe

    2017-01-01

    A major challenge limiting the practical applications of nanomaterials is that the activities of nanostructures (NSs) increase with reduced size, often sacrificing their stability in the chemical environment. Under oxidative conditions, NSs with smaller sizes and higher defect densities are commonly expected to oxidize more easily, since high-concentration defects can facilitate oxidation by enhancing the reactivity with O2 and providing a fast channel for oxygen incorporation. Here, using FeO NSs as an example, we show to the contrary, that reducing the size of active NSs can drastically increase their oxidation resistance. A maximum oxidation resistance is found for FeO NSs with dimensions below 3.2 nm. Rather than being determined by the structure or electronic properties of active sites, the enhanced oxidation resistance originates from the size-dependent structural dynamics of FeO NSs in O2. We find this dynamic size effect to govern the chemical properties of active NSs. PMID:28223687

  11. Effect of protein quality on recovery after intense resistance training.

    PubMed

    Rindom, E; Nielsen, M H; Kececi, K; Jensen, M E; Vissing, K; Farup, J

    2016-12-01

    The present study investigated the effects of high- versus low-quality protein supplementation on the regain of exercise performance during recovery from a period of high-intensity resistance training. In a diet-controlled crossover study, 12 resistance-trained participants performed two identical training periods, with each training period including four sessions of high-intensity resistance exercise during 5 days, while receiving either high- or low-quality protein. Prior to and at 3, 24 and 48 h after the training periods, performance was evaluated in knee extensor and flexor isometric maximal voluntary contraction (MVC), counter-movement jumping height (CMJ), and peak and mean anaerobic power. In addition, prior to and at 48 h after the training periods, performance in time-to-exhaustion at 70 % of VO2max (TTE) was evaluated. After the intense training periods, decrements in the order of 4-24 % were observed for MVCext, CMJ, mean anaerobic power, and TTE. In particular for TTE, this decrement in exercise performance did not attain full recovery at 48 h post-exercise. The regain of exercise performance was not dictated by type of protein supplement. The regain of muscle strength as well as anaerobic or aerobic performances were not markedly influenced by the type of protein supplement.

  12. Enhanced oxidation resistance of active nanostructures via dynamic size effect

    DOE PAGES

    Liu, Yun; Yang, Fan; Zhang, Yi; ...

    2017-02-22

    A major challenge limiting the practical applications of nanomaterials is that the activities of nanostructures (NSs) increase with reduced size, often sacrificing their stability in the chemical environment. Under oxidative conditions, NSs with smaller sizes and higher defect densities are commonly expected to oxidize more easily, since high-concentration defects can facilitate oxidation by enhancing the reactivity with O2 and providing a fast channel for oxygen incorporation. Here, using FeO NSs as an example, we show to the contrary, that reducing the size of active NSs can drastically increase their oxidation resistance. A maximum oxidation resistance is found for FeO NSsmore » with dimensions below 3.2 nm. Rather than being determined by the structure or electronic properties of active sites, the enhanced oxidation resistance originates from the size-dependent structural dynamics of FeO NSs in O2. We find this dynamic size effect to govern the chemical properties of active NSs.« less

  13. Effect of cements on fracture resistance of monolithic zirconia crowns

    PubMed Central

    Nakamura, Keisuke; Mouhat, Mathieu; Nergård, John Magnus; Lægreid, Solveig Jenssen; Kanno, Taro; Milleding, Percy; Örtengren, Ulf

    2016-01-01

    Abstract Objectives The present study investigated the effect of cements on fracture resistance of monolithic zirconia crowns in relation to their compressive strength. Materials and methods Four different cements were tested: zinc phosphate cement (ZPC), glass-ionomer cement (GIC), self-adhesive resin-based cement (SRC) and resin-based cement (RC). RC was used in both dual cure mode (RC-D) and chemical cure mode (RC-C). First, the compressive strength of each cement was tested according to a standard (ISO 9917-1:2004). Second, load-to-failure test was performed to analyze the crown fracture resistance. CAD/CAM-produced monolithic zirconia crowns with a minimal thickness of 0.5 mm were prepared and cemented to dies with each cement. The crown–die samples were loaded until fracture. Results The compressive strength of SRC, RC-D and RC-C was significantly higher than those of ZPC and GIC (p < 0.05). However, there was no significant difference in the fracture load of the crown between the groups. Conclusion The values achieved in the load-to-failure test suggest that monolithic zirconia crowns with a minimal thickness of 0.5 mm may have good resistance against fracture regardless of types of cements. PMID:27335900

  14. Synergistic effects of resistance training and protein intake: practical aspects.

    PubMed

    Guimarães-Ferreira, Lucas; Cholewa, Jason Michael; Naimo, Marshall Alan; Zhi, X I A; Magagnin, Daiane; de Sá, Rafaele Bis Dal Ponte; Streck, Emilio Luiz; Teixeira, Tamiris da Silva; Zanchi, Nelo Eidy

    2014-10-01

    Resistance training is a potent stimulus to increase skeletal muscle mass. The muscle protein accretion process depends on a robust synergistic action between protein intake and overload. The intake of protein after resistance training increases plasma amino acids, which results in the activation of signaling molecules leading to increased muscle protein synthesis (MPS) and muscle hypertrophy. Although both essential and non-essential amino acids are necessary for hypertrophy, the intake of free L-leucine or high-leucine whole proteins has been specifically shown to increase the initiation of translation that is essential for elevated MPS. The literature supports the use of protein intake following resistance-training sessions to enhance MPS; however, less understood are the effects of different protein sources and timing protocols on MPS. The sum of the adaptions from each individual training session is essential to muscle hypertrophy, and thus highlights the importance of an optimal supplementation protocol. The aim of this review is to present recent findings reported in the literature and to discuss the practical application of these results. In that light, new speculations and questions will arise that may direct future investigations. The information and recommendations generated in this review should be of benefit to clinical dietitians as well as those engaged in sports.

  15. Resistance to change and the law of effect

    PubMed Central

    Harper, David N.; McLean, Anthony P.

    1992-01-01

    Three experiments using multiple schedules of reinforcement explored the implications of resistance-to-change findings for the response-reinforcer relation described by the law of effect, using both steady-state responding and responding recorded in the first few sessions of conditions. In Experiment 1, when response-independent reinforcement was increased during a third component, response rate in Components 1 and 2 decreased. This response-rate reduction was proportionately greater in a component in which reinforcer magnitude was small (2-s access to wheat) than in the component in which it was large (6-s access to wheat). However, when reinforcer rates in the two components were varied together in Experiments 2 and 3, response-rate change was the same regardless of the magnitude of reinforcers used in the two components, so that sensitivity of response rates to reinforcer rates (Experiment 2) and of response-rate ratios to reinforcer-rate ratios (Experiment 3) was unaffected by the magnitude of the reinforcers. Therefore, the principles determining resistance to change, described by behavioral momentum theory, seem not to apply when the source of behavior change is the variation of reinforcement contingencies that maintain the behavior. The use of extinction as a manipulation to study resistance to change is questioned. PMID:16812656

  16. Separable metrics and radiating stars

    NASA Astrophysics Data System (ADS)

    Abebe, G. Z.; Maharaj, S. D.

    2017-01-01

    We study the junction condition relating the pressure to heat flux at the boundary of an accelerating and expanding spherically symmetric radiating star. We transform the junction condition to an ordinary differential equation by making a separability assumption on the metric functions in the space-time variables. The condition of separability on the metric functions yields several new exact solutions. A class of shear-free models is found which contains a linear equation of state and generalizes a previously obtained model. Four new shearing models are obtained; all the gravitational potentials can be written explicitly. A brief physical analysis indicates that the matter variables are well behaved.

  17. Thermodynamic Metrics and Optimal Paths

    SciTech Connect

    Sivak, David; Crooks, Gavin

    2012-05-08

    A fundamental problem in modern thermodynamics is how a molecular-scale machine performs useful work, while operating away from thermal equilibrium without excessive dissipation. To this end, we derive a friction tensor that induces a Riemannian manifold on the space of thermodynamic states. Within the linear-response regime, this metric structure controls the dissipation of finite-time transformations, and bestows optimal protocols with many useful properties. We discuss the connection to the existing thermodynamic length formalism, and demonstrate the utility of this metric by solving for optimal control parameter protocols in a simple nonequilibrium model.

  18. The flexibility of optical metrics

    NASA Astrophysics Data System (ADS)

    Bittencourt, Eduardo; Pereira, Jonas P.; Smolyaninov, Igor I.; Smolyaninova, Vera N.

    2016-08-01

    We firstly revisit the importance, naturalness and limitations of the so-called optical metrics for describing the propagation of light rays in the limit of geometric optics. We then exemplify their flexibility and nontriviality in some nonlinear material media and in the context of nonlinear theories of the electromagnetism, both in the presence of curved backgrounds, where optical metrics could be flat and inaccessible regions for the propagation of photons could be conceived, respectively. Finally, we underline and discuss the relevance and potential applications of our analyses in a broad sense, ranging from material media to compact astrophysical systems.

  19. Boundary effects on the magnetohydrodynamic stability of a resistive plasma

    NASA Astrophysics Data System (ADS)

    Velli, M.; Hood, A. W.; Einaudi, G.

    1990-02-01

    A general method for studying the resistive MHD stability of plasma configurations where boundary effects are of crucial importance and can be expressed as additional constraints on a periodic system is presented and applied to the case of line-tied cylindrically symmetric coronal loops. The eigenvalue equations obtained are a generalization of the Freidberg and Hewett equations, to which they reduce when the loop length is made infinite. An application to tearing modes is described which shows that in a finite geometry, tearing takes place at the center of the configuration, corresponding to the vertex of coronal loops. Applications to other configurations of astrophysical interest are described.

  20. The effect of propanidid on systemic vascular resistance in man.

    PubMed

    Klauber, P V; Christensen, V; Korshin, J; Skovsted, P

    1978-01-01

    We have studied the peripheral vascular effect in man of propanidid 6 mg/kg, administered as a bolus injection during cardiopulmonary by-pass with the aorta cross-clamped and at constant perfusion flow. Ten measurements in eight patients were performed. A decrease was found in systemic vascular resistance: from 150.7 +/- 16.3 to 99.5 +/- 10.1 kPa x s/1. No venous pooling occurred. It is concluded that, in man, propanidid causes a vasodilation which must contribute to the hypotension it causes.

  1. The Effect of Resistance on Rocket Injector Acoustics

    NASA Technical Reports Server (NTRS)

    Morgan, C. J.

    2015-01-01

    Combustion instability, where unsteady heat release couples with acoustic modes, has long been an area of concern in liquid rocket engines. Accurate modeling of the acoustic normal modes of the combustion chamber is important to understanding and preventing combustion instability. This study evaluates the effect of injector resistance on the mode shapes and complex eigen-frequencies of an injector/combustion chamber system by defining a high Mach-flow form of the convective wave equation (see Eq. 1) in COMSOL Multiphysics' Coefficient Form PDE Mathematics Module.

  2. Plasma stability theory including the resistive wall effects

    NASA Astrophysics Data System (ADS)

    Pustovitov, V. D.

    2015-12-01

    > Plasma stabilization due to a nearby conducting wall can provide access to better performance in some scenarios in tokamaks. This was proved by experiments with an essential gain in and demonstrated as a long-lasting effect at sufficiently fast plasma rotation in the DIII-D tokamak (see, for example, Strait et al., Nucl. Fusion, vol. 43, 2003, pp. 430-440). The rotational stabilization is the central topic of this review, though eventually the mode rotation gains significance. The analysis is based on the first-principle equations describing the energy balance with dissipation in the resistive wall. The method emphasizes derivation of the dispersion relations for the modes which are faster than the conventional resistive wall modes, but slower than the ideal magnetohydrodynamics modes. Both the standard thin wall and ideal-wall approximations are not valid in this range. Here, these are replaced by an approach incorporating the skin effect in the wall. This new element in the stability theory makes the energy sink a nonlinear function of the complex growth rate. An important consequence is that a mode rotating above a critical level can provide a damping effect sufficient for instability suppression. Estimates are given and applications are discussed.

  3. Effect of movement velocity during resistance training on neuromuscular performance.

    PubMed

    Pareja-Blanco, F; Rodríguez-Rosell, D; Sánchez-Medina, L; Gorostiaga, E M; González-Badillo, J J

    2014-10-01

    This study aimed to compare the effect on neuromuscular performance of 2 isoinertial resistance training programs that differed only in actual repetition velocity: maximal intended (MaxV) vs. half-maximal (HalfV) concentric velocity. 21 resistance-trained young men were randomly assigned to a MaxV (n=10) or HalfV (n=11) group and trained for 6 weeks using the full squat exercise. A complementary study (n=8) described the acute metabolic and mechanical response to the protocols used. MaxV training resulted in a likely more beneficial effect than HalfV on squat performance: maximum strength (ES: 0.94 vs. 0.54), velocity developed against all (ES: 1.76 vs. 0.88), light (ES: 1.76 vs. 0.75) and heavy (ES: 2.03 vs. 1.64) loads common to pre- and post-tests, and CMJ height (ES: 0.63 vs. 0.15). The effect on 20-m sprint was unclear, however. Both groups attained the greatest improvements in squat performance at their training velocities. Movement velocity seemed to be of greater importance than time under tension for inducing strength adaptations. Slightly higher metabolic stress (blood lactate and ammonia) and CMJ height loss were found for MaxV vs. HalfV, while metabolite levels were low to moderate for both conditions. MaxV may provide a superior stimulus for inducing adaptations directed towards improving athletic performance.

  4. Economic Metrics for Commercial Reusable Space Transportation Systems

    NASA Technical Reports Server (NTRS)

    Shaw, Eric J.; Hamaker, Joseph (Technical Monitor)

    2000-01-01

    The success of any effort depends upon the effective initial definition of its purpose, in terms of the needs to be satisfied and the goals to be fulfilled. If the desired product is "A System" that is well-characterized, these high-level need and goal statements can be transformed into system requirements by traditional systems engineering techniques. The satisfaction of well-designed requirements can be tracked by fairly straightforward cost, schedule, and technical performance metrics. Unfortunately, some types of efforts, including those that NASA terms "Programs," tend to resist application of traditional systems engineering practices. In the NASA hierarchy of efforts, a "Program" is often an ongoing effort with broad, high-level goals and objectives. A NASA "project" is a finite effort, in terms of budget and schedule, that usually produces or involves one System. Programs usually contain more than one project and thus more than one System. Special care must be taken in the formulation of NASA Programs and their projects, to ensure that lower-level project requirements are traceable to top-level Program goals, feasible with the given cost and schedule constraints, and measurable against top-level goals. NASA Programs and projects are tasked to identify the advancement of technology as an explicit goal, which introduces more complicating factors. The justification for funding of technology development may be based on the technology's applicability to more than one System, Systems outside that Program or even external to NASA. Application of systems engineering to broad-based technology development, leading to effective measurement of the benefits, can be valid, but it requires that potential beneficiary Systems be organized into a hierarchical structure, creating a "system of Systems." In addition, these Systems evolve with the successful application of the technology, which creates the necessity for evolution of the benefit metrics to reflect the changing

  5. Economic Metrics for Commercial Reusable Space Transportation Systems

    NASA Technical Reports Server (NTRS)

    Shaw, Eric J.; Hamaker, Joseph (Technical Monitor)

    2000-01-01

    The success of any effort depends upon the effective initial definition of its purpose, in terms of the needs to be satisfied and the goals to be fulfilled. If the desired product is "A System" that is well-characterized, these high-level need and goal statements can be transformed into system requirements by traditional systems engineering techniques. The satisfaction of well-designed requirements can be tracked by fairly straightforward cost, schedule, and technical performance metrics. Unfortunately, some types of efforts, including those that NASA terms "Programs," tend to resist application of traditional systems engineering practices. In the NASA hierarchy of efforts, a "Program" is often an ongoing effort with broad, high-level goals and objectives. A NASA "project" is a finite effort, in terms of budget and schedule, that usually produces or involves one System. Programs usually contain more than one project and thus more than one System. Special care must be taken in the formulation of NASA Programs and their projects, to ensure that lower-level project requirements are traceable to top-level Program goals, feasible with the given cost and schedule constraints, and measurable against top-level goals. NASA Programs and projects are tasked to identify the advancement of technology as an explicit goal, which introduces more complicating factors. The justification for funding of technology development may be based on the technology's applicability to more than one System, Systems outside that Program or even external to NASA. Application of systems engineering to broad-based technology development, leading to effective measurement of the benefits, can be valid, but it requires that potential beneficiary Systems be organized into a hierarchical structure, creating a "system of Systems." In addition, these Systems evolve with the successful application of the technology, which creates the necessity for evolution of the benefit metrics to reflect the changing

  6. Bergman kernel, balanced metrics and black holes

    NASA Astrophysics Data System (ADS)

    Klevtsov, Semyon

    In this thesis we explore the connections between the Kahler geometry and Landau levels on compact manifolds. We rederive the expansion of the Bergman kernel on Kahler manifolds developed by Tian, Yau, Zelditch, Lu and Catlin, using path integral and perturbation theory. The physics interpretation of this result is as an expansion of the projector of wavefunctions on the lowest Landau level, in the special case that the magnetic field is proportional to the Kahler form. This is a geometric expansion, somewhat similar to the DeWitt-Seeley-Gilkey short time expansion for the heat kernel, but in this case describing the long time limit, without depending on supersymmetry. We also generalize this expansion to supersymmetric quantum mechanics and more general magnetic fields, and explore its applications. These include the quantum Hall effect in curved space, the balanced metrics and Kahler gravity. In particular, we conjecture that for a probe in a BPS black hole in type II strings compactified on Calabi-Yau manifolds, the moduli space metric is the balanced metric.

  7. Guidelines for Teaching Metric Concepts.

    ERIC Educational Resources Information Center

    Wisconsin State Dept. of Public Instruction, Madison.

    The primary purpose of these guidelines is to provide teachers and other decision-makers with a suggested framework within which sound planning for metric education can be done. Student behavioral objectives are listed by topic. Each objective is coded to indicate grade level, topic, and objective number. A chart is provided to show a kindergarten…

  8. Metrical Phonology in Speech Production.

    ERIC Educational Resources Information Center

    Cooper, William E.; Eady, Stephen J.

    1986-01-01

    Describes several experiments which examined the basic claims of metrical phonology. The first two experiments examined the possible influences of stress clash in speech timing. The third and fourth experiments tested Hayes's (1984) analysis rule of quadrisyllabic meter; the fifth experiment included a basic test of the stress clash notion. (SED)

  9. Metric Units in Primary Schools.

    ERIC Educational Resources Information Center

    Lighthill, M. J.; And Others

    Although this pamphlet is intended as background material for teachers in English primary schools changing to the System International d'Unites (SI units), the form of the metric system being adopted by the United Kingdom, the educational implications of the change and the lists of apparatus suitable for use with children up to 14 years of age are…

  10. Improving an Imperfect Metric System

    ERIC Educational Resources Information Center

    Frasier, E. Lewis

    1974-01-01

    Suggests some improvements and additional units necessary for the International Metric System to expand its use to all measureable entities and defined quantities, especially in the measurement of time and angles. Included are tables of proposed unit systems in contrast with the presently available systems. (CC)

  11. Measuring in Metric. Student Version.

    ERIC Educational Resources Information Center

    Hawaii Univ., Honolulu. Curriculum Research and Development Group.

    This supplementary mathematics textbook is designed to teach pupils in the intermediate grades about the vocabulary and use of the metric system of measurement. The book limits exploration to the units of measurement for length, capacity, mass, temperature, area, and volume, with only the following prefixes considered: kilo, hecto, deka, deci,…

  12. Metrication in the Construction Industry

    ERIC Educational Resources Information Center

    Linden, Carl Vander

    1974-01-01

    Three groups appear to be in a position to lead the construction industry in adopting metrication: the building materials manufacturers industry associations, the architectural community, and the building code and standards organization. (A paper presented at Building Research Institute conference, Washington, D.C., November 27, 1973.) (Author/MLF)

  13. Guidelines for Teaching Metric Concepts.

    ERIC Educational Resources Information Center

    Wisconsin State Dept. of Public Instruction, Madison.

    The primary purpose of these guidelines is to provide teachers and other decision-makers with a suggested framework within which sound planning for metric education can be done. Student behavioral objectives are listed by topic. Each objective is coded to indicate grade level, topic, and objective number. A chart is provided to show a kindergarten…

  14. Metric-Free Distributional Comparisons.

    ERIC Educational Resources Information Center

    Haertel, Edward H.; And Others

    Two methods are presented for comparing distributions, such as achievement test score distributions, for distinctly different groups of persons in such a way that the comparison will not be influenced by the particular metric of the test being used. Both methods use percentile scores. One method, attributed to Flanagan, fits a straight line to the…

  15. Metrication and the Technical Teacher

    ERIC Educational Resources Information Center

    Irving, Michael

    1975-01-01

    The conclusion of the two-part feature on the S1 metric (International System of Units) reviews the basics and some of the rules technical teachers need to know in order to prepare their students for the changing world. (Author)

  16. Metric Measurement: Grades K-8.

    ERIC Educational Resources Information Center

    Instructional Objectives Exchange, Los Angeles, CA.

    This collection is comprised of 63 objectives and corresponding sample test items for evaluation of students in grades K-8. Correct answers or criteria for judging the adequacy of student responses are provided. Major categories in the collection are: (1) preparing to use the metric system--decimal and fractional notation; (2) measurement--length,…

  17. Improving an Imperfect Metric System

    ERIC Educational Resources Information Center

    Frasier, E. Lewis

    1974-01-01

    Suggests some improvements and additional units necessary for the International Metric System to expand its use to all measureable entities and defined quantities, especially in the measurement of time and angles. Included are tables of proposed unit systems in contrast with the presently available systems. (CC)

  18. Metrics in Education - Resource Materials.

    ERIC Educational Resources Information Center

    New York State Education Dept., Albany. Div. of Curriculum Development.

    This publication contains materials suitable for reproduction as transparencies or as classroom handouts. These metric materials may be used in a variety of occupational and practical arts courses. The format of the materials is in large print, some with humorous drawing; details of drawings and charts are easy to read. Introductory pages deal…

  19. Resources available for applying metrics in security and safety programming.

    PubMed

    Luizzo, Anthony

    2016-01-01

    Incorporating metrics into security surveys has been championed as a better way of substantiating program-related effectiveness and expenditures. Although security surveys have been aroundfor well over 40 years, rarely, if ever, have metric-related strategies been part of the equation, the author says. In this article, he cites several published articles and research findings available to security professionals and their surveyors that may give them the expertise and confidence they need to make use of this valuable tool.

  20. Developing Metrics for Effective Teaching in Extension Education: A Multi-State Factor-Analytic and Psychometric Analysis of Effective Teaching

    ERIC Educational Resources Information Center

    McKim, Billy R.; Lawver, Rebecca G.; Enns, Kellie; Smith, Amy R.; Aschenbrener, Mollie S.

    2013-01-01

    To successfully educate the public about agriculture, food, and natural resources, we must have effective educators in both formal and nonformal settings. Specifically, this study, which is a valuable part of a larger sequential mixed-method study addressing effective teaching in formal and nonformal agricultural education, provides direction for…

  1. Molecular Bases Determining Daptomycin Resistance-Mediated Resensitization to β-Lactams (Seesaw Effect) in Methicillin-Resistant Staphylococcus aureus

    PubMed Central

    Renzoni, Adriana; Kelley, William L.; Rosato, Roberto R.; Martinez, Maria P.; Roch, Melanie; Fatouraei, Maryam; Haeusser, Daniel P.; Margolin, William; Fenn, Samuel; Turner, Robert D.; Foster, Simon J.

    2016-01-01

    ABSTRACT Antimicrobial resistance is recognized as one of the principal threats to public health worldwide, yet the problem is increasing. Infections caused by methicillin-resistant Staphylococcus aureus (MRSA) strains are among the most difficult to treat in clinical settings due to the resistance of MRSA to nearly all available antibiotics. The cyclic anionic lipopeptide antibiotic daptomycin (DAP) is the clinical mainstay of anti-MRSA therapy. The decreased susceptibility to DAP (DAP resistance [DAPr]) reported in MRSA is frequently accompanied by a paradoxical decrease in β-lactam resistance, a process known as the “seesaw effect.” Despite the observed discordance in resistance phenotypes, the combination of DAP and β-lactams has been proven to be clinically effective for the prevention and treatment of infections due to DAPr MRSA strains. However, the mechanisms underlying the interactions between DAP and β-lactams are largely unknown. In the study described here, we studied the role of mprF with DAP-induced mutations in β-lactam sensitization and its involvement in the effective killing by the DAP-oxacillin (OXA) combination. DAP-OXA-mediated effects resulted in cell wall perturbations, including changes in peptidoglycan insertion, penicillin-binding protein 2 (PBP 2) delocalization, and reduced membrane amounts of PBP 2a, despite the increased transcription of mecA through mec regulatory elements. We have found that the VraSR sensor-regulator is a key component of DAP resistance, triggering mutated mprF-mediated cell membrane (CM) modifications that result in impairment of PrsA location and chaperone functions, both of which are essential for PBP 2a maturation, the key determinant of β-lactam resistance. These observations provide for the first time evidence that synergistic effects between DAP and β-lactams involve PrsA posttranscriptional regulation of CM-associated PBP 2a. PMID:27795377

  2. The effect of electrical conductivity on pore resistance and electroporation

    NASA Astrophysics Data System (ADS)

    Li, Jianbo; Lin, Hao

    2008-11-01

    Electroporation is an elegant means to gain access to the cytoplasm, and to deliver molecules into the cell while simultaneously maintaining viability and functionality. In this technique, an applied electric pulse transiently permeabilizes the cell membrane, through which biologically active agents such as DNA, RNA, and amino acids can enter the cell, and perform tasks such as gene and cancer therapy. Despite wide applications, current electroporation technologies fall short of desired efficiency and reliability, in part due to the lack of fundamental understanding and quantitative modeling tools. This work focuses on the modeling of cell membrane conductance due to the formation of aqueous conducting pores. An analytical expression is developed to determine effective pore resistance as a function of the membrane thickness, pore size, and intracellular and extracellular conductivities. The availability of this expression avoids empirical or ad hoc specification of the conductivity of the pore-filling solution which was adopted in previous works. Such pore resistance model is then incorporated into a whole-cell electroporation simulation to investigate the effect of conductivity ratio on membrane permeabilization. The results reveal that the degree of permeabilization strongly depends on the specific values of the extracellular and intracellular conductivities.

  3. Effect of Coffee and Caffeine Ingestion on Resistance Exercise Performance.

    PubMed

    Richardson, Darren L; Clarke, Neil D

    2016-10-01

    Richardson, DL and Clarke, ND. Effect of coffee and caffeine ingestion on resistance exercise performance. J Strength Cond Res 30(10): 2892-2900, 2016-The aim of the present study was to determine the effect of ingesting caffeine dose-matched anhydrous caffeine, coffee, or decaffeinated coffee plus anhydrous caffeine during resistance exercise on performance. Nine resistance-trained men (mean ± SD: age, 24 ± 2 years; weight, 84 ± 8 kg; height, 180 ± 8 cm) completed a squat and bench press exercise protocol at 60% 1 repetition maximum until failure on 5 occasions consuming 0.15 g·kg caffeinated coffee (COF), 0.15 g·kg decaffeinated coffee (DEC), 0.15 g·kg decaffeinated coffee plus 5 mg·kg anhydrous caffeine (D + C), 5 mg·kg anhydrous caffeine (CAF), or a placebo (PLA). Felt arousal and rating of perceived exertion (RPE) were used to assess perceptual variables and heart rate (HR) to assess physiological responses between trials. There were significant differences in total weight lifted for the squat between conditions (p < 0.01; (Equation is included in full-text article.)= 0.54) with a greater amount lifted during D + C compared with DEC (p < 0.01), CAF (p ≤ 0.05), and PLA (p ≤ 0.05) conditions. Total weight lifted during the COF condition was significantly greater than that lifted under PLA (p < 0.01), although not significantly greater than the amount of weight lifted during the DEC condition (p = 0.082). No significant differences were observed in total weight lifted in the bench press protocol between conditions (p = 0.186; (Equation is included in full-text article.)= 0.17). Significant differences in HR (p < 0.01; (Equation is included in full-text article.)= 0.39) but not RPE (squat: p = 0.690; (Equation is included in full-text article.)= 0.07; bench press: p = 0.165; (Equation is included in full-text article.)= 0.18) and felt arousal (p = 0.056; (Equation is included in full-text article.)= 0.24) were observed between conditions. Coffee and

  4. Semantic Metrics for Analysis of Software

    NASA Technical Reports Server (NTRS)

    Etzkorn, Letha H.; Cox, Glenn W.; Farrington, Phil; Utley, Dawn R.; Ghalston, Sampson; Stein, Cara

    2005-01-01

    A recently conceived suite of object-oriented software metrics focus is on semantic aspects of software, in contradistinction to traditional software metrics, which focus on syntactic aspects of software. Semantic metrics represent a more human-oriented view of software than do syntactic metrics. The semantic metrics of a given computer program are calculated by use of the output of a knowledge-based analysis of the program, and are substantially more representative of software quality and more readily comprehensible from a human perspective than are the syntactic metrics.

  5. Psychotropic placebos create resistance to the misinformation effect.

    PubMed

    Clifasefi, Seema L; Garry, Maryanne; Harper, David N; Sharman, Stefanie J; Sutherland, Rachel

    2007-02-01

    Can a placebo for a psychotropic drug help participants resist the misinformation effect? To answer this question, we gave participants a mixture of baking soda and water and told half of them that the mixture was a cognition-enhancing drug called R273 and told the other half that it was an inactive version of the drug. Shortly thereafter, all participants took part in a three-stage misinformation experiment. Compared with participants who were told that they had taken the placebo, the participants who were told that they had taken the drug reported improved cognitive abilities and were less susceptible to the misinformation effect. We provide source-monitoring and mindfulness accounts of our findings.

  6. A study of a proposed modified torsional agility metric

    NASA Technical Reports Server (NTRS)

    Valasek, John; Eggold, David P.; Downing, David R.

    1991-01-01

    A new candidate lateral agility metric, the modified torsional agility parameter, is proposed and tested through generic, nonlinear, non-real-time flight simulation programs of the F-18 and F-5A. The metric is aimed at quantifying high subsonic loaded roll capabilities which might be useful in modern air combat. The metric is considered to be straightforward for testing and measuring based on nonreal-time unmanned flight simulation. The metric is found to be sensitive to pilot input errors of less than full lateral stick to capture bank angle, when tested using unmanned flight simulations. It is suggested that, for redesigned configurations of both aircraft with improved lateral agility, the major benefit would be provided by fast and highly effective rudders, and a high level of pitch, roll, and yaw damping at moderate to high normal load factor levels.

  7. Conformal Gravity and the Alcubierre Warp Drive Metric

    NASA Astrophysics Data System (ADS)

    Varieschi, Gabriele; Burstein, Zily

    2013-04-01

    We present an analysis of the classic Alcubierre metric based on conformal gravity, rather than standard general relativity. The main characteristics of the resulting warp drive remain the same as in the original study by Alcubierre, namely that effective super-luminal motion is a viable outcome of the metric. We show that for particular choices of the shaping function, the Alcubierre metric in the context of conformal gravity does not violate the weak energy condition, as was the case of the original solution. In particular, the resulting warp drive does not require the use of exotic matter. Therefore, if conformal gravity is a correct extension of general relativity, super-luminal motion via an Alcubierre metric might be a realistic solution, thus allowing faster-than-light interstellar travel.

  8. Non-metric variation of the infracranial skeleton.

    PubMed Central

    Finnegan, M

    1978-01-01

    196 skeletons of known age, sex and rac from the Terry Collection were studied in order to document 30 non-metric infracranial traits. Each trait had the ability to be expressed bilaterally, although significant side dimorphism was not observed. Sex differences were statistically significant for some of the traits within a racial group, but these differences were not as pronounced as the differences generated by non-metric cranial traits in the same populations, and were not effective in all racial groups. In general, these infracranial traits show some age dependency when correlation statistics are used, but this dependency is lost when the more robust chi 2 statistic is used. These data suggest that infracranial non-metric traits may be superior to cranial non-metric traits for population comparisons. Infracranial traits may be more durable than cranial traits having regard to the nature of most archaeological material. PMID:632214

  9. Hi Metric Fans! We're the Metric Mice. Elementary Metric Project Awareness Booklet.

    ERIC Educational Resources Information Center

    Huber, Roland B.

    An overview and samples of some of the materials contained in the Elementary Metric Project's curriculum for grades 1-6 are presented. Information is given concerning the adoption of the program. The sample activity sheets deal with linear measurement, mass, volume, and temperature. (MP)

  10. The drug resistance strategies intervention: program effects on substance use.

    PubMed

    Hecht, Michael L; Graham, John W; Elek, Elvira

    2006-01-01

    This study evaluates the Drug Resistance Strategies (DRS) project, a culturally grounded, communication-based substance use prevention program implemented in 35 middle schools in Phoenix, Arizona. The intervention consisted of 10 lessons taught by the classroom teacher that imparted the knowledge, motivation, and skills needed to resist drug offers. The evaluation used growth modeling to analyze significant differences in average postintervention substance use (alcohol, cigarettes, and marijuana) and growth of use over the course of the study. The study involved 6,298 seventh graders (65% Mexican/Mexican American) who responded to at least 1 of 4 questionnaires (1 pretest and 3 follow-up measures). When compared to a control group, the DRS intervention appeared to significantly limit the increase in the number of students reporting recent substance use, especially alcohol and marijuana use. The multicultural version of the curriculum proved most broadly effective, followed by the version targeting Mexican American youth. The development of a culturally grounded prevention curriculum for Mexican American youth expands the population being served by interventions. Moreover, the success of the multicultural curriculum version, which has the broadest application, provides particular promise, and the article demonstrates how a growth modeling approach can be used to evaluate a communication-based intervention by analyzing changes over time rather than differences between the pretest and posttest scores.

  11. Resistivity and thickness effects in dendritic web silicon solar cells

    NASA Technical Reports Server (NTRS)

    Meier, D. L.; Hwang, J. M.; Greggi, J.; Campbell, R. B.

    1987-01-01

    The decrease of minority carrier lifetime as resistivity decreases in dendritic-web silicon solar cells is addressed. This variation is shown to be consistent with the presence of defect levels in the bandgap which arise from extended defects in the web material. The extended defects are oxide precipitates (SiOx) and the dislocation cores they decorate. Sensitivity to this background distribution of defect levels increases with doping because the Fermi level moves closer to the majority carrier band edge. For high-resistivity dendritic-web silicon, which has a low concentration of these extended defects, cell efficiencies as high as 16.6 percent (4 sq cm, 40 ohm-cm boron-doped base, AM1.5 global, 100 mW/sq cm, 25 C JPL LAPSS1 measurement) and a corresponding electron lifetime of 38 microsec have been obtained. Thickness effects occur in bifacial cell designs and in designs which use light trapping. In some cases, the dislocation/precipitate defect can be passivated through the full thickness of web cells by hydrogen ion implantation.

  12. Persuasive communication: A theoretical model for changing the attitude of preservice elementary teachers toward metric conversion

    NASA Astrophysics Data System (ADS)

    Shrigley, Robert L.

    This study was based on Hovland's four-part statement, Who says what to whom with what effect, the rationale for persuasive communication, a theoretical model for modifying attitudes. Part I was a survey of 139 perservice elementary teachers from which were generated the more credible characteristics of metric instructors, a central element in the who component of Hovland's model. They were: (1) background in mathematics and science, (2) fluency in metrics, (3) capability of thinking metrically, (4) a record of excellent teaching, (5) previous teaching of metric measurement to children, (6) responsibility for teaching metric content in methods courses and (7) an open enthusiasm for metric conversion. Part II was a survey of 45 mathematics educators where belief statements were synthesized for the what component of Hovland's model. It found that math educators support metric measurement because: (1) it is consistent with our monetary system; (2) the conversion of units is easier into metric than English; (3) it is easier to teach and easier to learn than English measurement; there is less need for common fractions; (4) most nations use metric measurement; scientists have used it for decades; (5) American industry has begun to use it; (6) metric measurement will facilitate world trade and communication; and (7) American children will need it as adults; educational agencies are mandating it. With the who and what of Hovland's four-part statement defined, educational researchers now have baseline data to use in testing experimentally the effect of persuasive communication on the attitude of preservice teachers toward metrication.

  13. Evaluating the relationship between biotic and sediment metrics using mesocosms and field studies.

    PubMed

    Conroy, E; Turner, J N; Rymszewicz, A; Bruen, M; O'Sullivan, J J; Lawler, D M; Lally, H; Kelly-Quinn, M

    2016-10-15

    An ongoing research challenge is the detection of biological responses to elevated sediment and the identification of sediment-specific bioassessment metrics to evaluate these biological responses. Laboratory mesocosms and field observations in rivers in Ireland were used to evaluate the relationship between a range of biological and sediment metrics and to assess which biological metrics were best at discerning the effects of excess sediment on macroinvertebrates. Results from the mesocosm study indicated a marked decrease in the abundance of sensitive taxa with increasing sediment surface cover. % EPT (Ephemeroptera, Plecoptera, Trichoptera) and % E abundances exhibited the strongest negative correlation with sediment surface cover in the mesocosm study. The field study revealed that % EPT abundance was most closely correlated with % sediment surface cover, explaining 13% of the variance in the biological metric. Both studies revealed weaker relationships with a number of other taxonomy-based metrics including total taxon abundance, total taxon richness and moderate relationships with the Proportion of Sediment-sensitive Invertebrates metric (PSI). All trait-based metrics were poorly correlated with sediment surface cover in the field study. In terms of sediment metrics, % surface cover was more closely related to biological metrics than either re-suspendable sediment or turbidity. These results indicate that % sediment surface cover and % EPT abundance may be useful metrics for assessing the effect of excessive sediment on macroinvertebrates. However, EPT metrics may not be specific to sediment impact and therefore when applied to rivers with multiple pressures should be combined with observations on sediment cover.

  14. The Effects of Manual Resistance Training on Fitness in Adolescents

    PubMed Central

    Dorgo, Sandor; King, George A.; Candelaria, Norma; Bader, Julia O.; Brickey, Gregory D.; Adams, Carolyn E.

    2010-01-01

    Manual Resistance Training (MRT), an alternative to traditional resistance training, requires minimal equipment and may be effective when applied in school-based physical education (PE) classes. The purpose of this study was to document the physical changes in adolescents (N = 222) using MRT in school-based PE settings. Six fitness tests from the Fitnessgram assessment tool were selected to assess students' cardiovascular and muscular fitness and skin-fold tests were used to assess body composition. One Control and two Experimental Groups were defined. The Control group of students (N = 129) attended regular PE classes. One Experimental group (N = 63) attended PE that was complemented by the MRT system. A second Experiment group (N = 30) attended PE complemented by MRT and cardiovascular endurance training. Using the selected Fitnessgram tests post-test measurements were done after 9 and 18 weeks of PE. At baseline, there were no significant differences between the three groups for most measures. Compared to baseline, experimental groups improved significantly in all six fitness measures and showed more improvements than the Control group in most fitness measures both at 9 and 18 weeks. None of the groups showed significant improvement in body composition. The results documented that an MRT complemented PE program was effective in improving adolescents' muscular fitness. An 18-week combined MRT and cardiovascular endurance training program effectively improved cardiovascular and muscular fitness but was ineffective in improving adolescent body composition. An MRT based exercise session requires minimal equipment and set-up, and can be performed in a short period of time, therefore it is suitable for application in regular PE settings. PMID:19826296

  15. Effects of cementation surface modifications on fracture resistance of zirconia.

    PubMed

    Srikanth, Ramanathan; Kosmac, Tomaz; Della Bona, Alvaro; Yin, Ling; Zhang, Yu

    2015-04-01

    To examine the effects of glass infiltration (GI) and alumina coating (AC) on the indentation flexural load and four-point bending strength of monolithic zirconia. Plate-shaped (12 mm × 12 mm × 1.0 mm or 1.5 or 2.0 mm) and bar-shaped (4 mm × 3 mm × 25 mm) monolithic zirconia specimens were fabricated. In addition to monolithic zirconia (group Z), zirconia monoliths were glass-infiltrated or alumina-coated on their tensile surfaces to form groups ZGI and ZAC, respectively. They were also glass-infiltrated on their upper surfaces, and glass-infiltrated or alumina-coated on their lower (tensile) surfaces to make groups ZGI2 and ZAC2, respectively. For comparison, porcelain-veneered zirconia (group PVZ) and monolithic lithium disilicate glass-ceramic (group LiDi) specimens were also fabricated. The plate-shaped specimens were cemented onto a restorative composite base for Hertzian indentation using a tungsten carbide spherical indenter with a radius of 3.2mm. Critical loads for indentation flexural fracture at the zirconia cementation surface were measured. Strengths of bar-shaped specimens were evaluated in four-point bending. Glass infiltration on zirconia tensile surfaces increased indentation flexural loads by 32% in Hertzian contact and flexural strength by 24% in four-point bending. Alumina coating showed no significant effect on resistance to flexural damage of zirconia. Monolithic zirconia outperformed porcelain-veneered zirconia and monolithic lithium disilicate glass-ceramics in terms of both indentation flexural load and flexural strength. While both alumina coating and glass infiltration can be used to effectively modify the cementation surface of zirconia, glass infiltration can further increase the flexural fracture resistance of zirconia. Copyright © 2015 Academy of Dental Materials. Published by Elsevier Ltd. All rights reserved.

  16. Effects of cementation surface modifications on fracture resistance of zirconia

    PubMed Central

    Srikanth, Ramanathan; Kosmac, Tomaz; Bona, Alvaro Della; Yin, Ling; Zhang, Yu

    2015-01-01

    Objectives To examine the effects of glass infiltration (GI) and alumina coating (AC) on the indentation flexural load and four-point bending strength of monolithic zirconia. Methods Plate-shaped (12 mm × 12 mm × 1.0 mm or 1.5 mm or 2.0 mm) and bar-shaped (4 mm × 3 mm × 25 mm) monolithic zirconia specimens were fabricated. In addition to monolithic zirconia (group Z), zirconia monoliths were glass-infiltrated or alumina-coated on their tensile surfaces to form groups ZGI and ZAC, respectively. They were also glass-infiltrated on their upper surfaces, and glass-infiltrated or alumina-coated on their lower (tensile) surfaces to make groups ZGI2 and ZAC2, respectively. For comparison, porcelain-veneered zirconia (group PVZ) and monolithic lithium disilicate glass-ceramic (group LiDi) specimens were also fabricated. The plate-shaped specimens were cemented onto a restorative composite base for Hertzian indentation using a tungsten carbide spherical indenter with a radius of 3.2 mm. Critical loads for indentation flexural fracture at the zirconia cementation surface were measured. Strengths of bar-shaped specimens were evaluated in four-point bending. Results Glass infiltration on zirconia tensile surfaces increased indentation flexural loads by 32% in Hertzian contact and flexural strength by 24% in four-point bending. Alumina coating showed no significant effect on resistance to flexural damage of zirconia. Monolithic zirconia outperformed porcelain-veneered zirconia and monolithic lithium disilicate glass-ceramics in terms of both indentation flexural load and flexural strength. Significance While both alumina coating and glass infiltration can be used to effectively modify the cementation surface of zirconia, glass infiltration can further increase the flexural fracture resistance of zirconia. PMID:25687628

  17. Measure Metric: A Multi-State Consortium

    ERIC Educational Resources Information Center

    Dowling, Kenneth W.

    1977-01-01

    Describes the "Measure Metric" series of twelve fifteen-minute programs and related classroom materials for grades 5 and 6 for teaching the metric system and the International System of Units (SI). (SL)

  18. Hands-On Activities with Metrics

    ERIC Educational Resources Information Center

    McFee, Evan

    1978-01-01

    Suggestions for familiarizing elementary teachers with the use of the metric system are given. These include a "stair-steps" method of converting units within the metric system and estimation and measurement activities using familiar everyday objects. (MN)

  19. Do Your Students Measure Up Metrically?

    ERIC Educational Resources Information Center

    Taylor, P. Mark; Simms, Ken; Kim, Ok-Kyeong; Reys, Robert E.

    2001-01-01

    Examines released metric items from the Third International Mathematics and Science Study (TIMSS) and the 3rd and 4th grade results. Recommends refocusing instruction on the metric system to improve student performance in measurement. (KHR)

  20. Think Metric: It's All Around Us.

    ERIC Educational Resources Information Center

    Learning, 1988

    1988-01-01

    Class activities designed to instruct young students in the use of the metric system of measurement are illustrated on a larger poster. Ideas for measuring, thinking and writing in metric are presented for children of different ages. (JD)

  1. Measuring Sustainability: Deriving Metrics From Objectives (Presentation)

    EPA Science Inventory

    The definition of 'sustain', to keep in existence, provides some insight into the metrics that are required to measure sustainability and adequately respond to assure sustainability. Keeping something in existence implies temporal and spatial contexts and requires metrics that g...

  2. Sustainability Metrics: The San Luis Basin Project

    EPA Science Inventory

    Sustainability is about promoting humanly desirable dynamic regimes of the environment. Metrics: ecological footprint, net regional product, exergy, emergy, and Fisher Information. Adaptive management: (1) metrics assess problem, (2) specific problem identified, and (3) managemen...

  3. Sustainability Metrics: The San Luis Basin Project

    EPA Science Inventory

    Sustainability is about promoting humanly desirable dynamic regimes of the environment. Metrics: ecological footprint, net regional product, exergy, emergy, and Fisher Information. Adaptive management: (1) metrics assess problem, (2) specific problem identified, and (3) managemen...

  4. Measuring Sustainability: Deriving Metrics From Objectives (Presentation)

    EPA Science Inventory

    The definition of 'sustain', to keep in existence, provides some insight into the metrics that are required to measure sustainability and adequately respond to assure sustainability. Keeping something in existence implies temporal and spatial contexts and requires metrics that g...

  5. Fuzzy polynucleotide spaces and metrics.

    PubMed

    Nieto, Juan J; Torres, A; Georgiou, D N; Karakasidis, T E

    2006-04-01

    The study of genetic sequences is of great importance in biology and medicine. Mathematics is playing an important role in the study of genetic sequences and, generally, in bioinformatics. In this paper, we extend the work concerning the Fuzzy Polynucleotide Space (FPS) introduced in Torres, A., Nieto, J.J., 2003. The fuzzy polynucleotide Space: Basic properties. Bioinformatics 19(5); 587-592 and Nieto, J.J., Torres, A., Vazquez-Trasande, M.M. 2003. A metric space to study differences between polynucleotides. Appl. Math. Lett. 27:1289-1294: by studying distances between nucleotides and some complete genomes using several metrics. We also present new results concerning the notions of similarity, difference and equality between polynucleotides. The results are encouraging since they demonstrate how the notions of distance and similarity between polynucleotides in the FPS can be employed in the analysis of genetic material.

  6. Metrics for Labeled Markov Systems

    NASA Technical Reports Server (NTRS)

    Desharnais, Josee; Jagadeesan, Radha; Gupta, Vineet; Panangaden, Prakash

    1999-01-01

    Partial Labeled Markov Chains are simultaneously generalizations of process algebra and of traditional Markov chains. They provide a foundation for interacting discrete probabilistic systems, the interaction being synchronization on labels as in process algebra. Existing notions of process equivalence are too sensitive to the exact probabilities of various transitions. This paper addresses contextual reasoning principles for reasoning about more robust notions of "approximate" equivalence between concurrent interacting probabilistic systems. The present results indicate that:We develop a family of metrics between partial labeled Markov chains to formalize the notion of distance between processes. We show that processes at distance zero are bisimilar. We describe a decision procedure to compute the distance between two processes. We show that reasoning about approximate equivalence can be done compositionally by showing that process combinators do not increase distance. We introduce an asymptotic metric to capture asymptotic properties of Markov chains; and show that parallel composition does not increase asymptotic distance.

  7. Object-oriented productivity metrics

    NASA Technical Reports Server (NTRS)

    Connell, John L.; Eller, Nancy

    1992-01-01

    Software productivity metrics are useful for sizing and costing proposed software and for measuring development productivity. Estimating and measuring source lines of code (SLOC) has proven to be a bad idea because it encourages writing more lines of code and using lower level languages. Function Point Analysis is an improved software metric system, but it is not compatible with newer rapid prototyping and object-oriented approaches to software development. A process is presented here for counting object-oriented effort points, based on a preliminary object-oriented analysis. It is proposed that this approach is compatible with object-oriented analysis, design, programming, and rapid prototyping. Statistics gathered on actual projects are presented to validate the approach.

  8. Metric reconstruction from Weyl scalars

    NASA Astrophysics Data System (ADS)

    Whiting, Bernard F.; Price, Larry R.

    2005-08-01

    The Kerr geometry has remained an elusive world in which to explore physics and delve into the more esoteric implications of general relativity. Following the discovery, by Kerr in 1963, of the metric for a rotating black hole, the most major advance has been an understanding of its Weyl curvature perturbations based on Teukolsky's discovery of separable wave equations some ten years later. In the current research climate, where experiments across the globe are preparing for the first detection of gravitational waves, a more complete understanding than concerns just the Weyl curvature is now called for. To understand precisely how comparatively small masses move in response to the gravitational waves they emit, a formalism has been developed based on a description of the whole spacetime metric perturbation in the neighbourhood of the emission region. Presently, such a description is not available for the Kerr geometry. While there does exist a prescription for obtaining metric perturbations once curvature perturbations are known, it has become apparent that there are gaps in that formalism which are still waiting to be filled. The most serious gaps include gauge inflexibility, the inability to include sources—which are essential when the emitting masses are considered—and the failure to describe the ell = 0 and 1 perturbation properties. Among these latter properties of the perturbed spacetime, arising from a point mass in orbit, are the perturbed mass and axial component of angular momentum, as well as the very elusive Carter constant for non-axial angular momentum. A status report is given on recent work which begins to repair these deficiencies in our current incomplete description of Kerr metric perturbations.

  9. A stationary q-metric

    NASA Astrophysics Data System (ADS)

    Toktarbay, S.; Quevedo, H.

    2014-10-01

    We present a stationary generalization of the static $q-$metric, the simplest generalization of the Schwarzschild solution that contains a quadrupole parameter. It possesses three independent parameters that are related to the mass, quadrupole moment and angular momentum. We investigate the geometric and physical properties of this exact solution of Einstein's vacuum equations, and show that it can be used to describe the exterior gravitational field of rotating, axially symmetric, compact objects.

  10. Multi-Metric Sustainability Analysis

    SciTech Connect

    Cowlin, Shannon; Heimiller, Donna; Macknick, Jordan; Mann, Margaret; Pless, Jacquelyn; Munoz, David

    2014-12-01

    A readily accessible framework that allows for evaluating impacts and comparing tradeoffs among factors in energy policy, expansion planning, and investment decision making is lacking. Recognizing this, the Joint Institute for Strategic Energy Analysis (JISEA) funded an exploration of multi-metric sustainability analysis (MMSA) to provide energy decision makers with a means to make more comprehensive comparisons of energy technologies. The resulting MMSA tool lets decision makers simultaneously compare technologies and potential deployment locations.

  11. Science and Technology Transition Metrics

    DTIC Science & Technology

    2004-03-01

    for Research", Science, Volume 277, 1 August 1997. Kostoff, R. N., "The Use and Misuse of Citation Analysis in Research Evaluation", Scientometrics ...The Metrics of Science and Technology”. Scientometrics . 50:2. 353-361. February 2001. Kostoff, R. N., and Schaller, R. R. "Science and...37. 604-606. September 2001. Kostoff, R. N. “Citation Analysis for Research Performer Quality”. Scientometrics . 53:1. 49-71. 2002. VII

  12. Sensory Metrics of Neuromechanical Trust.

    PubMed

    Softky, William; Benford, Criscillia

    2017-09-01

    Today digital sources supply a historically unprecedented component of human sensorimotor data, the consumption of which is correlated with poorly understood maladies such as Internet addiction disorder and Internet gaming disorder. Because both natural and digital sensorimotor data share common mathematical descriptions, one can quantify our informational sensorimotor needs using the signal processing metrics of entropy, noise, dimensionality, continuity, latency, and bandwidth. Such metrics describe in neutral terms the informational diet human brains require to self-calibrate, allowing individuals to maintain trusting relationships. With these metrics, we define the trust humans experience using the mathematical language of computational models, that is, as a primitive statistical algorithm processing finely grained sensorimotor data from neuromechanical interaction. This definition of neuromechanical trust implies that artificial sensorimotor inputs and interactions that attract low-level attention through frequent discontinuities and enhanced coherence will decalibrate a brain's representation of its world over the long term by violating the implicit statistical contract for which self-calibration evolved. Our hypersimplified mathematical understanding of human sensorimotor processing as multiscale, continuous-time vibratory interaction allows equally broad-brush descriptions of failure modes and solutions. For example, we model addiction in general as the result of homeostatic regulation gone awry in novel environments (sign reversal) and digital dependency as a sub-case in which the decalibration caused by digital sensorimotor data spurs yet more consumption of them. We predict that institutions can use these sensorimotor metrics to quantify media richness to improve employee well-being; that dyads and family-size groups will bond and heal best through low-latency, high-resolution multisensory interaction such as shared meals and reciprocated touch; and

  13. Effects of pharmacological agents on subcortical resistance shifts

    NASA Technical Reports Server (NTRS)

    Klivington, K. A.

    1975-01-01

    Microliter quantities of tetrodotoxin, tetraethylammonium chloride, and picrotoxin injected into the inferior colliculus and superior olive of unanesthetized cats differentially affect the amplitude and waveform of click-evoked potentials and evoked resistance shifts. Tetrodotoxin simultaneously reduces the negative phase of the evoked potential and eliminates the evoked resistance shift. Tetraethylammonium enhances the negative evoked potential component, presumably of postsynaptic origin, without significantly altering evoked resistance shift amplitude. Picrotoxin also enhances the negative evoked potential wave but increases evoked resistance shift amplitude. These findings implicate events associated with postsynaptic membrane depolarization in the production of the evoked resistance shift.

  14. Effect of Lipid Materials on Heat Resistance of Bacterial Spores

    PubMed Central

    Molin, N.; Snygg, B. G.

    1967-01-01

    The apparent heat resistance of spores of Bacillus megaterium, B. subtilis, B. cereus, B. stearothermophilus, and Clostridium botulinum type E in lipids was investigated and compared with the resistance of the spores in phosphate buffer solution. The most pronounced increase in heat resistance was noted for B. subtilis and C. botulinum type E, the increase varying with the type of lipid used. A high water content of the lipids used as heating menstruum lowered the heat resistance of the spores. Possible explanations for the high heat resistance of spores in lipids are discussed. PMID:16349757

  15. [The effect of antibacterial substances on spread resistance of bacteria].

    PubMed

    Chojecka, Agnieszka; Jakimiak, Bozenna; Röhm-Rodowald, Ewa; Podgórska, Marta

    2010-01-01

    The evaluation of influence biocides on phenomenon of spread resistance bacteria is wide discussed particularly in the medical area. Current issue is examinated mechanisms of spread bacterial resistance in the areas using antibiotics and disinfectants and in natural environment. Selection of resistance bacteria is connected with using biocides against the rules in medical care and disinfection. Biocides using in static concentrations do not act as bacteriocidal substances and contribute to survival rate of resistance bacteria. Disinfectants use correctly to the areas and in right using concentrations prevent spread of resistance bacteria.

  16. Effects of pharmacological agents on subcortical resistance shifts

    NASA Technical Reports Server (NTRS)

    Klivington, K. A.

    1975-01-01

    Microliter quantities of tetrodotoxin, tetraethylammonium chloride, and picrotoxin injected into the inferior colliculus and superior olive of unanesthetized cats differentially affect the amplitude and waveform of click-evoked potentials and evoked resistance shifts. Tetrodotoxin simultaneously reduces the negative phase of the evoked potential and eliminates the evoked resistance shift. Tetraethylammonium enhances the negative evoked potential component, presumably of postsynaptic origin, without significantly altering evoked resistance shift amplitude. Picrotoxin also enhances the negative evoked potential wave but increases evoked resistance shift amplitude. These findings implicate events associated with postsynaptic membrane depolarization in the production of the evoked resistance shift.

  17. Visual metrics: discriminative power through flexibility.

    PubMed

    Janssen, T J; Blommaert, F J

    2000-01-01

    An important stage in visual processing is the quantification of optical attributes of the outside world. We argue that the metrics used for this quantification are flexible, and that this flexibility is exploited to optimise the discriminative power of the metrics. We derive mathematical expressions for such optimal metrics and show that they exhibit properties resembling well-known visual phenomena. To conclude, we discuss some of the implications of flexible metrics for visual identification.

  18. A normalized Levenshtein distance metric.

    PubMed

    Yujian, Li; Bo, Liu

    2007-06-01

    Although a number of normalized edit distances presented so far may offer good performance in some applications, none of them can be regarded as a genuine metric between strings because they do not satisfy the triangle inequality. Given two strings X and Y over a finite alphabet, this paper defines a new normalized edit distance between X and Y as a simple function of their lengths (|X| and |Y|) and the Generalized Levenshtein Distance (GLD) between them. The new distance can be easily computed through GLD with a complexity of O(|X|.|Y|) and it is a metric valued in [0, 1] under the condition that the weight function is a metric over the set of elementary edit operations with all costs of insertions/deletions having the same weight. Experiments using the AESA algorithm in handwritten digit recognition show that the new distance can generally provide similar results to some other normalized edit distances and may perform slightly better if the triangle inequality is violated in a particular data set.

  19. The effect of different resistivity models on magnetotail dynamics

    NASA Technical Reports Server (NTRS)

    Lyon, J. G.; Fedder, J. A.; Huba, J. D.

    1986-01-01

    Two-dimensional, time-dependent MHD simulations of the interaction between the solar wind and the earth's magnetosphere have been performed to study magnetotail dynamics with varying forms of anomalous resistivity. In general, the resulting models conform to the neutral line model proposed for substorms with near-earth x points and high-speed tailward flows occurring in the magnetotail. However, in the case where Joule heating is included in the physical description of the system, the near-earth x point never moves far down tail, and high-speed tailward flows never stop. Only in the case where there is no Joule heating does the x point move down tail. Simultaneously, the high-speed tailward flows cease. These results indicate that the mechanism of energy dissipation can have an important effect on reconnection processes and the global magnetospheric dynamics.

  20. Resistance of platelet proteins to effects of ionizing radiation

    SciTech Connect

    Prodouz, K.N.; Habraken, J.W.; Moroff, G. )

    1990-12-01

    Gamma irradiation of blood components prevents lymphocyte-induced graft-versus-host disease after transfusion in immunocompromised individuals. In this report we demonstrate the resistance of blood platelet proteins to gamma radiation-induced protein cleavage and aggregate formation when platelet concentrates were treated with a dose of 5000 rad. Results of one- and two-dimensional sodium dodecyl sulfate-polyacrylamide gel electrophoresis of total platelet protein and cytoskeletal protein preparations indicate that platelet proteins are neither cleaved nor cross-linked under these conditions of irradiation. These results support those of a previous study that documented the lack of any adverse effect of 5000 rad gamma radiation on in vitro platelet properties.