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Sample records for diversity effects drive

  1. TeenDrivingPlan effectiveness: the effect of quantity and diversity of supervised practice on teens' driving performance.

    Science.gov (United States)

    Mirman, Jessica H; Albert, W Dustin; Curry, Allison E; Winston, Flaura K; Fisher Thiel, Megan C; Durbin, Dennis R

    2014-11-01

    The large contribution of inexperience to the high crash rate of newly licensed teens suggests that they enter licensure with insufficient skills. In a prior analysis, we found moderate support for a direct effect of a web-based intervention, the TeenDrivingPlan (TDP), on teens' driving performance. The purpose of the present study was to identify the mechanisms by which TDP may be effective and to extend our understanding of how teens learn to drive. A randomized controlled trial conducted with teen permit holders and parent supervisors (N = 151 dyads) was used to determine if the effect of TDP on driver performance operated through five hypothesized mediators: (1) parent-perceived social support; (2) teen-perceived social support; (3) parent engagement; (4) practice quantity; and (5) practice diversity. Certified driving evaluators, blinded to teens' treatment allocation, assessed teens' driving performance 24 weeks after enrollment. Mediator variables were assessed on self-report surveys administered periodically over the study period. Exposure to TDP increased teen-perceived social support, parent engagement, and practice diversity. Both greater practice quantity and diversity were associated with better driving performance, but only practice diversity mediated the relationship between TDP and driver performance. Practice diversity is feasible to change and increases teens' likelihood of completing a rigorous on-road driving assessment just before licensure. Future research should continue to identify mechanisms that diversify practice driving, explore complementary ways to help families optimize the time they spend on practice driving, and evaluate the long-term effectiveness of TDP. Copyright © 2014 Society for Adolescent Health and Medicine. Published by Elsevier Inc. All rights reserved.

  2. Diverse Teams Drive Leadership Development

    DEFF Research Database (Denmark)

    Holck, Lotte; Hjortlund Andersen, Lotte

    New research from ISS Denmark shows that leading diverse teams strengthens leaders’ competencies within communication, relationship building and talent development and ensures inclusion. This has a reinforcing effect as the better the leadership, the better the heterogeneous team will function....

  3. How does pedogenesis drive plant diversity?

    Science.gov (United States)

    Laliberté, Etienne; Grace, James B.; Huston, Michael A.; Lambers, Hans; Teste, François P.; Turner, Benjamin L.; Wardle, David A.

    2013-01-01

    Some of the most species-rich plant communities occur on ancient, strongly weathered soils, whereas those on recently developed soils tend to be less diverse. Mechanisms underlying this well-known pattern, however, remain unresolved. Here, we present a conceptual model describing alternative mechanisms by which pedogenesis (the process of soil formation) might drive plant diversity. We suggest that long-term soil chronosequences offer great, yet largely untapped, potential as 'natural experiments' to determine edaphic controls over plant diversity. Finally, we discuss how our conceptual model can be evaluated quantitatively using structural equation modeling to advance multivariate theories about the determinants of local plant diversity. This should help us to understand broader-scale diversity patterns, such as the latitudinal gradient of plant diversity.

  4. Genetic Competence Drives Genome Diversity in Bacillus subtilis

    Science.gov (United States)

    Chevreux, Bastien; Serra, Cláudia R; Schyns, Ghislain; Henriques, Adriano O

    2018-01-01

    Abstract Prokaryote genomes are the result of a dynamic flux of genes, with increases achieved via horizontal gene transfer and reductions occurring through gene loss. The ecological and selective forces that drive this genomic flexibility vary across species. Bacillus subtilis is a naturally competent bacterium that occupies various environments, including plant-associated, soil, and marine niches, and the gut of both invertebrates and vertebrates. Here, we quantify the genomic diversity of B. subtilis and infer the genome dynamics that explain the high genetic and phenotypic diversity observed. Phylogenomic and comparative genomic analyses of 42 B. subtilis genomes uncover a remarkable genome diversity that translates into a core genome of 1,659 genes and an asymptotic pangenome growth rate of 57 new genes per new genome added. This diversity is due to a large proportion of low-frequency genes that are acquired from closely related species. We find no gene-loss bias among wild isolates, which explains why the cloud genome, 43% of the species pangenome, represents only a small proportion of each genome. We show that B. subtilis can acquire xenologous copies of core genes that propagate laterally among strains within a niche. While not excluding the contributions of other mechanisms, our results strongly suggest a process of gene acquisition that is largely driven by competence, where the long-term maintenance of acquired genes depends on local and global fitness effects. This competence-driven genomic diversity provides B. subtilis with its generalist character, enabling it to occupy a wide range of ecological niches and cycle through them. PMID:29272410

  5. Diversification vs diversity : what will drive diversity in the future

    International Nuclear Information System (INIS)

    Brummell, A.

    1998-01-01

    The issue of what the energy industry of the future will look like was discussed. The core competencies needed for the future, the ways in which they could change the business model for energy companies, and the history of the industry vis-a-vis diversification were outlined. The current forces driving the change towards diversification were identified as technology impacts, deregulation and open competition. The implication of these forces on the structure of the industry were probed. It was concluded that future opportunities for the industry will be influenced by these forces, but the major beneficiaries will be companies that will rely on knowledge not only of technology, but new competencies and business ideas, the ability to develop new markets, new products and emphasize knowledge to leverage assets

  6. Quantum effects in warp drives

    Directory of Open Access Journals (Sweden)

    Finazzi Stefano

    2013-09-01

    Full Text Available Warp drives are interesting configurations that, at least theoretically, provide a way to travel at superluminal speed. Unfortunately, several issues seem to forbid their realization. First, a huge amount of exotic matter is required to build them. Second, the presence of quantum fields propagating in superluminal warp-drive geometries makes them semiclassically unstable. Indeed, a Hawking-like high-temperature flux of particles is generated inside the warp-drive bubble, which causes an exponential growth of the energy density measured at the front wall of the bubble by freely falling observers. Moreover, superluminal warp drives remain unstable even if the Lorentz symmetry is broken by the introduction of regulating higher order terms in the Lagrangian of the quantum field. If the dispersion relation of the quantum field is subluminal, a black-hole laser phenomenon yields an exponential amplification of the emitted flux. If it is superluminal, infrared effects cause a linear growth of this flux.

  7. Cannabis effects on driving skills.

    Science.gov (United States)

    Hartman, Rebecca L; Huestis, Marilyn A

    2013-03-01

    Cannabis is the most prevalent illicit drug identified in impaired drivers. The effects of cannabis on driving continue to be debated, making prosecution and legislation difficult. Historically, delays in sample collection, evaluating the inactive Δ(9)-tetrahydrocannabinol (THC) metabolite 11-nor-9-carboxy-THC, and polydrug use have complicated epidemiologic evaluations of driver impairment after cannabis use. We review and evaluate the current literature on cannabis' effects on driving, highlighting the epidemiologic and experimental data. Epidemiologic data show that the risk of involvement in a motor vehicle accident (MVA) increases approximately 2-fold after cannabis smoking. The adjusted risk of driver culpability also increases substantially, particularly with increased blood THC concentrations. Studies that have used urine as the biological matrix have not shown an association between cannabis and crash risk. Experimental data show that drivers attempt to compensate by driving more slowly after smoking cannabis, but control deteriorates with increasing task complexity. Cannabis smoking increases lane weaving and impaired cognitive function. Critical-tracking tests, reaction times, divided-attention tasks, and lane-position variability all show cannabis-induced impairment. Despite purported tolerance in frequent smokers, complex tasks still show impairment. Combining cannabis with alcohol enhances impairment, especially lane weaving. Differences in study designs frequently account for inconsistencies in results between studies. Participant-selection bias and confounding factors attenuate ostensible cannabis effects, but the association with MVA often retains significance. Evidence suggests recent smoking and/or blood THC concentrations 2-5 ng/mL are associated with substantial driving impairment, particularly in occasional smokers. Future cannabis-and-driving research should emphasize challenging tasks, such as divided attention, and include occasional and

  8. Cannabis Effects on Driving Skills

    Science.gov (United States)

    Hartman, Rebecca L.; Huestis, Marilyn A.

    2013-01-01

    BACKGROUND Cannabis is the most prevalent illicit drug identified in impaired drivers. The effects of cannabis on driving continue to be debated, making prosecution and legislation difficult. Historically, delays in sample collection, evaluating the inactive Δ9-tetrahydrocannabinol (THC) metabolite 11-nor-9-carboxy-THC, and polydrug use have complicated epidemiologic evaluations of driver impairment after cannabis use. CONTENT We review and evaluate the current literature on cannabis’ effects on driving, highlighting the epidemiologic and experimental data. Epidemiologic data show that the risk of involvement in a motor vehicle accident (MVA) increases approximately 2-fold after cannabis smoking. The adjusted risk of driver culpability also increases substantially, particularly with increased blood THC concentrations. Studies that have used urine as the biological matrix have not shown an association between cannabis and crash risk. Experimental data show that drivers attempt to compensate by driving more slowly after smoking cannabis, but control deteriorates with increasing task complexity. Cannabis smoking increases lane weaving and impaired cognitive function. Critical-tracking tests, reaction times, divided-attention tasks, and lane-position variability all show cannabis-induced impairment. Despite purported tolerance in frequent smokers, complex tasks still show impairment. Combining cannabis with alcohol enhances impairment, especially lane weaving. SUMMARY Differences in study designs frequently account for inconsistencies in results between studies. Participant-selection bias and confounding factors attenuate ostensible cannabis effects, but the association with MVA often retains significance. Evidence suggests recent smoking and/or blood THC concentrations 2–5 ng/mL are associated with substantial driving impairment, particularly in occasional smokers. Future cannabis-and-driving research should emphasize challenging tasks, such as divided attention

  9. Novel CRISPR/Cas9 gene drive constructs reveal insights into mechanisms of resistance allele formation and drive efficiency in genetically diverse populations.

    Directory of Open Access Journals (Sweden)

    Jackson Champer

    2017-07-01

    Full Text Available A functioning gene drive system could fundamentally change our strategies for the control of vector-borne diseases by facilitating rapid dissemination of transgenes that prevent pathogen transmission or reduce vector capacity. CRISPR/Cas9 gene drive promises such a mechanism, which works by converting cells that are heterozygous for the drive construct into homozygotes, thereby enabling super-Mendelian inheritance. Although CRISPR gene drive activity has already been demonstrated, a key obstacle for current systems is their propensity to generate resistance alleles, which cannot be converted to drive alleles. In this study, we developed two CRISPR gene drive constructs based on the nanos and vasa promoters that allowed us to illuminate the different mechanisms by which resistance alleles are formed in the model organism Drosophila melanogaster. We observed resistance allele formation at high rates both prior to fertilization in the germline and post-fertilization in the embryo due to maternally deposited Cas9. Assessment of drive activity in genetically diverse backgrounds further revealed substantial differences in conversion efficiency and resistance rates. Our results demonstrate that the evolution of resistance will likely impose a severe limitation to the effectiveness of current CRISPR gene drive approaches, especially when applied to diverse natural populations.

  10. Engagement with the TeenDrivingPlan and diversity of teens' supervised practice driving: lessons for internet-based learner driver interventions.

    Science.gov (United States)

    Winston, Flaura K; Mirman, Jessica H; Curry, Allison E; Pfeiffer, Melissa R; Elliott, Michael R; Durbin, Dennis R

    2015-02-01

    Inexperienced, less-skilled driving characterises many newly licensed drivers and contributes to high crash rates. A randomised trial of TeenDrivingPlan (TDP), a new learner driver phase internet-based intervention, demonstrated effectiveness in improving safety relevant, on-road driving behaviour, primarily through greater driving practice diversity. To inform future learner driver interventions, this analysis examined TDP use and its association with practice diversity. Posthoc analysis of data from teen/parent dyads (n=107), enrolled early in learner phase and assigned to treatment arm in randomised trial. Inserted software beacons captured TDP use data. Electronic surveys completed by parents and teens assessed diversity of practice driving and TDP usability ratings at 24 weeks (end of study period). Most families (84%) used TDP early in the learner period; however, the number of TDP sessions in the first week was three times higher among dyads who achieved greater practice diversity than those with less. By week five many families still engaged with TDP, but differences in TDP use could not be detected between families with high versus low practice diversity. Usability was not a major issue for this sample based on largely positive user ratings. An engaging internet-based intervention, such as TDP, can support families in achieving high practice diversity. Future learner driver interventions should provide important information early in the learner period when engagement is greatest, encourage continued learning as part of logging practice drives, and incorporate monitoring software for further personalisation to meet family needs. NCT01498575. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

  11. Host diversity and latitude drive the trematode diversity patterns in the European freshwater fauna

    DEFF Research Database (Denmark)

    Thieltges, David W.; Hof, Christian; Dehling, D. Matthias

    2011-01-01

    biogeographical regions in Europe from the Limnofauna Europaea and used multiple regression analyses to test for correlations between the diversity of definitive (vertebrates) or first intermediate (gastropods) hosts and that of trematodes, and for latitudinal gradients in trematode diversity. In particular, we...... faunas. Results Latitude or first intermediate host richness had no effect on trematode richness, but definitive host richness was a strong predictor of trematode richness, among both allogenic and autogenic parasites. We found that beta diversity of trematode faunas within latitudinal bands decreased...... to the north, with similar values for allogenic and autogenic trematodes. Finally, we observed an increasing proportion of autogenic species toward the north of Europe. Main conclusions The richness of definitive hosts appears to be the driver of trematode diversity at a continental scale. The latitudinal...

  12. Factors driving the global decline of cycad diversity.

    Science.gov (United States)

    Mankga, Ledile T; Yessoufou, Kowiyou

    2017-07-01

    Mounting evidence indicates that we are witnessing the sixth mass extinction period. Given the important goods and services biodiversity delivers to humans, there is a need for a continued commitment to investigate what pre-disposes some taxa to greater risk of extinction. Here, we investigate this question using a phylogenetic comparative method and fitting a cumulative link mixed effect model on biological, ecological and evolutionary data of cycads, the most threatened lineage in the plant kingdom. We identified nine groups of threats to cycads, with habitat loss, over-collection, fire and reproduction failure being the most prominent, but only four of these threats (habitat loss, over-collection, medicinal uses and reproduction failure) clustered on the cycad tree of life. This clustering suggests that closely related species may be exposed to similar threats, perhaps because of geographic regionalization of cycad genera. Nonetheless, the diversity of threats and several variables linked to the biology and ecology of cycads correlate with extinction risk (e.g. altitude, height, diameter, geographic range), and different variables seem to be linked to different IUCN status of cycads. Although their predictive power is generally extinction risk in cycads and, since most threats that we identified as drivers of extinction risk of cycads are anthropogenically mediated, we recommend stronger legislation to regulate human-cycad interactions and the commitment of all governments globally to implement this regulation.

  13. Mutualistic interactions drive ecological niche convergence in a diverse butterfly community.

    Science.gov (United States)

    Elias, Marianne; Gompert, Zachariah; Jiggins, Chris; Willmott, Keith

    2008-12-02

    Ecological communities are structured in part by evolutionary interactions among their members. A number of recent studies incorporating phylogenetics into community ecology have upheld the paradigm that competition drives ecological divergence among species of the same guild. However, the role of other interspecific interactions, in particular positive interactions such as mutualism, remains poorly explored. We characterized the ecological niche and inferred phylogenetic relationships among members of a diverse community of neotropical Müllerian mimetic butterflies. Müllerian mimicry is one of the best studied examples of mutualism, in which unpalatable species converge in wing pattern locally to advertize their toxicity to predators. We provide evidence that mutualistic interactions can drive convergence along multiple ecological axes, outweighing both phylogeny and competition in shaping community structure. Our findings imply that ecological communities are adaptively assembled to a much greater degree than commonly suspected. In addition, our results show that phenotype and ecology are strongly linked and support the idea that mimicry can cause ecological speciation through multiple cascading effects on species' biology.

  14. Mutualistic interactions drive ecological niche convergence in a diverse butterfly community.

    Directory of Open Access Journals (Sweden)

    Marianne Elias

    2008-12-01

    Full Text Available Ecological communities are structured in part by evolutionary interactions among their members. A number of recent studies incorporating phylogenetics into community ecology have upheld the paradigm that competition drives ecological divergence among species of the same guild. However, the role of other interspecific interactions, in particular positive interactions such as mutualism, remains poorly explored. We characterized the ecological niche and inferred phylogenetic relationships among members of a diverse community of neotropical Müllerian mimetic butterflies. Müllerian mimicry is one of the best studied examples of mutualism, in which unpalatable species converge in wing pattern locally to advertize their toxicity to predators. We provide evidence that mutualistic interactions can drive convergence along multiple ecological axes, outweighing both phylogeny and competition in shaping community structure. Our findings imply that ecological communities are adaptively assembled to a much greater degree than commonly suspected. In addition, our results show that phenotype and ecology are strongly linked and support the idea that mimicry can cause ecological speciation through multiple cascading effects on species' biology.

  15. Effects of advertising billboards during simulated driving.

    Science.gov (United States)

    Edquist, Jessica; Horberry, Tim; Hosking, Simon; Johnston, Ian

    2011-05-01

    There is currently a great deal of interest in the problem of driver distraction. Most research focuses on distractions from inside the vehicle, but drivers can also be distracted by objects outside the vehicle. Major roads are increasingly becoming sites for advertising billboards, and there is little research on the potential effects of this advertising on driving performance. The driving simulator experiment presented here examines the effects of billboards on drivers, including older and inexperienced drivers who may be more vulnerable to distractions. The presence of billboards changed drivers' patterns of visual attention, increased the amount of time needed for drivers to respond to road signs, and increased the number of errors in this driving task. Copyright © 2010 Elsevier Ltd and The Ergonomics Society. All rights reserved.

  16. Factors driving the global decline of cycad diversity

    OpenAIRE

    Mankga, Ledile T.; Yessoufou, Kowiyou

    2017-01-01

    Abstract Mounting evidence indicates that we are witnessing the sixth mass extinction period. Given the important goods and services biodiversity delivers to humans, there is a need for a continued commitment to investigate what pre-disposes some taxa to greater risk of extinction. Here, we investigate this question using a phylogenetic comparative method and fitting a cumulative link mixed effect model on biological, ecological and evolutionary data of cycads, the most threatened lineage in ...

  17. A study on the effects of fatigue driving and drunk driving on drivers' physical characteristics.

    Science.gov (United States)

    Zhang, Xingjian; Zhao, Xiaohua; Du, Hongji; Rong, Jian

    2014-01-01

    The purpose of this study was to analyze the effects of fatigue driving and drunk driving on drivers' physical characteristics; to analyze the differences in drivers' physical characteristics affected by different kinds of fatigue; and to compare the differences in the effects of the 2 driving states, fatigue driving and drunk driving. Twenty-five participants' physical characteristics were collected under 5 controlled situations: normal, tired driving, drowsy driving, drowsiness + tired driving, and drunk driving. In this article, fatigue driving refers to tiredness and drowsiness and includes 3 situations: tired driving, drowsy driving, and drowsiness + tired driving. The drivers' physical characteristics were measured in terms of 9 parameters: systolic blood pressure (SBP), heart rate (HR), eyesight, dynamic visual acuity (DVA), time for dark adaption (TDA), reaction time to sound (RTS), reaction time to light (RTL), deviation of depth perception (DDP), and time deviation of speed anticipation (TDSA). They were analyzed using analysis of variance (ANOVA) with repeated measures. Binary logistical regression analysis was used to explain the relationship between drivers' physical characteristics and the two driving states. Most of the drivers' physical characteristic parameters were found to be significantly different under the influence of different situations. Four indicators are significantly affected by fatigue driving during deep fatigue (in decreasing order of influence): HR, RTL, SBP and RTS. HR and RTL are significant in the logistical regression model of the drowsiness + tired driving situation and normal situations. Six indicators of the drivers' physical characteristics are significantly affected by drunk driving (in decreasing order of influence): SBP, RTL, DDP, eyesight, RTS, and TDSA. SBP and DDP have a significant effect in the logistical regression model of the drunk driving situation and the normal situation. Both fatigue driving and drunk driving

  18. Effect of the teen driving plan on the driving performance of teenagers before licensure: a randomized clinical trial.

    Science.gov (United States)

    Mirman, Jessica H; Curry, Allison E; Winston, Flaura K; Wang, Wenli; Elliott, Michael R; Schultheis, Maria T; Fisher Thiel, Megan C; Durbin, Dennis R

    2014-08-01

    Many studies have failed to show an effect of parent-supervised practice driving on the driving performance of teenagers; nevertheless, most Graduated Driver Licensing programs have provisions that require supervised practice. To determine whether a web-based intervention, the Teen Driving Plan (TDP), can improve the driving performance of teenagers before licensure as measured by the Teen On-road Driving Assessment (tODA). Randomized, single-blind, clinical trial among 217 dyads (1 parent: 1 teenaged learner's-permit holder) to test TDP effectiveness on increasing the quantity and diversity of supervised practice and improving the teenagers' prelicensed driving performance. The study was conducted from December 2011 through January 2013 in Southeastern Pennsylvania. Dyads were randomized (3:2) to receive the TDP or the Pennsylvania driver's manual (control group). The TDP is a psychoeducational intervention designed to increase the quantity and diversity of parent-supervised practice. Materials are grouped by the following driving environments: empty parking lots, suburban residential streets, intermediate (1- or 2-lane) roads, highways, rural roads with curves and elevation changes, and commercial districts. The main outcomes were self-reported practice driving across 6 environments and 2 conditions and driving performance as measured by the teenagers' completion of the standardized and validated tODA 24 weeks after enrollment. Certified professional driving evaluators blinded to randomization status terminated the tODA if they determined that the teenager could not safely complete it. We examined mean differences in the quantity of supervised practice, differences in the overall proportion of teenagers in each group that had assessments terminated for unsafe driving, and the point of termination during the assessment. The TDP dyads reported more practice in 5 of the 6 environments and at night and in bad weather compared with the control dyads. Overall, 5 of 86

  19. Concerta cf Ritalin Effects on Driving Performance

    Directory of Open Access Journals (Sweden)

    J Gordon Millichap

    2004-03-01

    Full Text Available The effects of different methylphenidate (MPH delivery profiles on driving performance of 6 male ADHD adolescents, aged 16 to 19 years, were evaluated by a randomized, crossover, single-blind study comparing controlled-release (OROS MPH (Concerta given q.d. to immediate-release MPH (Ritalin in equal doses t.i.d. in a study at the University of Virginia, Charlottesville, VA.

  20. [Effects of global change on soil fauna diversity: A review].

    Science.gov (United States)

    Wu, Ting-Juan

    2013-02-01

    Terrestrial ecosystem consists of aboveground and belowground components, whose interaction affects the ecosystem processes and functions. Soil fauna plays an important role in biogeochemical cycles. With the recognizing of the significance of soil fauna in ecosystem processes, increasing evidences demonstrated that global change has profound effects on soil faunima diversity. The alternation of land use type, the increasing temperature, and the changes in precipitation pattern can directly affect soil fauna diversity, while the increase of atmospheric CO2 concentration and nitrogen deposition can indirectly affect the soil fauna diversity by altering plant community composition, diversity, and nutrient contents. The interactions of different environmental factors can co-affect the soil fauna diversity. To understand the effects of different driving factors on soil fauna diversity under the background of climate change would facilitate us better predicting how the soil fauna diversity and related ecological processes changed in the future.

  1. Design of diverse safety rod and its drive mechanism of PFBR

    International Nuclear Information System (INIS)

    Vijayashree, R.; Govindarajan, S.; Chetal, S.C.

    1997-01-01

    In Prototype Fast Breeder Reactor (PFBR), there are two types of absorber rods for control and shutdown of the reactor in the event of any abnormal event. They are: (i) Control and Safety Rod (CSR) and (ii) the Diverse Safety Rod (DSR). Of these, the former (CSR) caters to the control function of the reactor during normal operating conditions and to the shutdown during abnormal situations. The DSR, on the other hand is meant essentially for the reactor shutdown to take care of any abnormal transient. It is rather important to note that functionally the DSR is independent of CSR in the sense, that it can bring the reactor to a cold shutdown state and maintain it even under the hypothetical condition of the failure of CSR. From the design point of view, this stipulates a failure probability of less than 10 -4 per demand. The DSR is normally parked above the core by the Diverse Safety Rod Drive Mechanism (DSRDM). On receiving a scram signal it gets released from the holding electromagnet and falls under the gravity into the core. Diverse features are incorporated both in the absorber rods and in the drive mechanisms to avoid common mode failures. This paper discusses the salient features of DSR and DSRDM. A brief account of detailed design, analysis and development of two important subassemblies viz. electromagnet and sodium dash pot is also presented. In addition, a brief comparison between CSR and DSR including their drive mechanisms is also provided. (author)

  2. Two decades of climate driving the dynamics of functional and taxonomic diversity of a tropical small mammal community in western Mexico

    OpenAIRE

    Mason-Romo, Edgard David; Farías, Ariel A.; Ceballos, Gerardo

    2017-01-01

    Understanding the effects of global climate disruption on biodiversity is important to future conservation efforts. While taxonomic diversity is widely studied, functional diversity of plants, and recently animals, is receiving increasing attention. Most studies of mammals are short-term, focus on temperate habitats, and rely on traits described in the literature rather than generating traits from observations. Unlike previous studies, this long-term field study assessed the factors driving t...

  3. Effects of chewing gum on driving performance as evaluated by the STISIM driving simulator

    OpenAIRE

    Yoo, Ingyu; Kim, Eun-Joo; Lee, Joo-Hyun

    2015-01-01

    [Purpose] The purpose of this study was to determine the effects of chewing gum on driving performance in a driving simulator. [Subjects] In total, 26 young licensed drivers participated. [Methods] The driving scenario was typical of an urban environment: a single-carriageway, two-way road consisting of a mix of curved and straight sections, with considerable levels of traffic, pedestrians, and parked cars. Mean distance driven above the speed limit, lane position, mean distance driven across...

  4. Electron acceptors for anaerobic oxidation of methane drive microbial community structure and diversity in mud volcanoes.

    Science.gov (United States)

    Ren, Ge; Ma, Anzhou; Zhang, Yanfen; Deng, Ye; Zheng, Guodong; Zhuang, Xuliang; Zhuang, Guoqiang; Fortin, Danielle

    2018-04-06

    Mud volcanoes (MVs) emit globally significant quantities of methane into the atmosphere, however, methane cycling in such environments is not yet fully understood, as the roles of microbes and their associated biogeochemical processes have been largely overlooked. Here, we used data from high-throughput sequencing of microbial 16S rRNA gene amplicons from six MVs in the Junggar Basin in northwest China to quantify patterns of diversity and characterize the community structure of archaea and bacteria. We found anaerobic methanotrophs and diverse sulfate- and iron-reducing microbes in all of the samples, and the diversity of both archaeal and bacterial communities was strongly linked to the concentrations of sulfate, iron and nitrate, which could act as electron acceptors in anaerobic oxidation of methane (AOM). The impacts of sulfate/iron/nitrate on AOM in the MVs were verified by microcosm experiments. Further, two representative MVs were selected to explore the microbial interactions based on phylogenetic molecular ecological networks. The sites showed distinct network structures, key species and microbial interactions, with more complex and numerous linkages between methane-cycling microbes and their partners being observed in the iron/sulfate-rich MV. These findings suggest that electron acceptors are important factors driving the structure of microbial communities in these methane-rich environments. © 2018 The Authors. Environmental Microbiology published by Society for Applied Microbiology and John Wiley & Sons Ltd.

  5. Effect of consecutive driving on accident risk: a comparison between passenger and freight train driving.

    Science.gov (United States)

    Chang, Hsin-Li; Ju, Lai-Shun

    2008-11-01

    This study combined driver-responsible accidents with on-board driving hours to examine the effect of consecutive driving on the accident risk of train operations. The data collected from the Taiwan Railway Administration for the period 1996-2006 was used to compute accident rates for varied accumulated driving hours for passenger and freight trains. The results showed that accident risk grew with increased consecutive driving hours for both passenger and freight trains, and doubled that of the first hour after four consecutive hours of driving. Additional accident risk was found for freight trains during the first hour due to required shunting in the marshalling yards where there are complex track layouts and semi-automatic traffic controls. Also, accident risk for train driving increased more quickly over consecutive driving hours than for automobile driving, and accumulated fatigue caused by high working pressure and monotony of the working environment are considered to be the part of the reason. To prevent human errors accidents, enhancing safety equipment, driver training programs, and establishing a sound auditing system are suggested and discussed.

  6. Effect of chronic nonmalignant pain on highway driving performance.

    Science.gov (United States)

    Veldhuijzen, D S; van Wijck, A J M; Wille, F; Verster, J C; Kenemans, J L; Kalkman, C J; Olivier, B; Volkerts, E R

    2006-05-01

    Most pain patients are treated in an outpatient setting and are engaged in daily activities including driving. Since several studies showed that cognitive functioning may be impaired in chronic nonmalignant pain, the question arises whether or not chronic nonmalignant pain affects driving performance. Therefore, the objective of the present study was to determine the effects of chronic nonmalignant pain on actual highway driving performance during normal traffic. Fourteen patients with chronic nonmalignant pain and 14 healthy controls, matched on age, educational level, and driving experience, participated in the study. Participants performed a standardized on-the-road driving test during normal traffic, on a primary highway. The primary parameter of the driving test is the Standard Deviation of Lateral Position (SDLP). In addition, driving-related skills (tracking, divided attention, and memory) were examined in the laboratory. Subjective assessments, such as pain intensity, and subjective driving quality, were rated on visual analogue scales. The results demonstrated that a subset of chronic nonmalignant pain patients had SDLPs that were higher than the matched healthy controls, indicating worse highway driving performance. Overall, there was a statistically significant difference in highway driving performance between the groups. Further, chronic nonmalignant pain patients rated their subjective driving quality to be normal, although their ratings were significantly lower than those of the healthy controls. No significant effects were found on the laboratory tests.

  7. Driving with the wandering mind: the effect that mind-wandering has on driving performance.

    Science.gov (United States)

    Yanko, Matthew R; Spalek, Thomas M

    2014-03-01

    The principal objective of the present work was to examine the effects of mind state (mind-wandering vs. on-task) on driving performance in a high-fidelity driving simulator. Mind-wandering is thought to interfere with goal-directed thought. It is likely, then, that when driving, mind-wandering might lead to impairments in critical aspects of driving performance. In two experiments, we assess the extent to which mind-wandering interferes with responsiveness to sudden events, mean velocity, and headway distance. Using a car-following procedure in a high-fidelity driving simulator, participants were probed at random times to indicate whether they were on-task at that moment or mind-wandering. The dependent measures were analyzed based on the participant's response to the probe. Compared to when on-task, when mind-wandering participants showed longer response times to sudden events, drove at a higher velocity, and maintained a shorter headway distance. Collectively, these findings indicate that mind-wandering affects a broad range of driving responses and may therefore lead to higher crash risk. The results suggest that situations that are likely associated with mind-wandering (e.g., route familiarity) can impair driving performance.

  8. Metagenomic potential for and diversity of N-cycle driving microorganisms in the Bothnian Sea sediment.

    Science.gov (United States)

    Rasigraf, Olivia; Schmitt, Julia; Jetten, Mike S M; Lüke, Claudia

    2017-08-01

    The biological nitrogen cycle is driven by a plethora of reactions transforming nitrogen compounds between various redox states. Here, we investigated the metagenomic potential for nitrogen cycle of the in situ microbial community in an oligotrophic, brackish environment of the Bothnian Sea sediment. Total DNA from three sediment depths was isolated and sequenced. The characterization of the total community was performed based on 16S rRNA gene inventory using SILVA database as reference. The diversity of diagnostic functional genes coding for nitrate reductases (napA;narG), nitrite:nitrate oxidoreductase (nxrA), nitrite reductases (nirK;nirS;nrfA), nitric oxide reductase (nor), nitrous oxide reductase (nosZ), hydrazine synthase (hzsA), ammonia monooxygenase (amoA), hydroxylamine oxidoreductase (hao), and nitrogenase (nifH) was analyzed by blastx against curated reference databases. In addition, Polymerase chain reaction (PCR)-based amplification was performed on the hzsA gene of anammox bacteria. Our results reveal high genomic potential for full denitrification to N 2 , but minor importance of anaerobic ammonium oxidation and dissimilatory nitrite reduction to ammonium. Genomic potential for aerobic ammonia oxidation was dominated by Thaumarchaeota. A higher diversity of anammox bacteria was detected in metagenomes than with PCR-based technique. The results reveal the importance of various N-cycle driving processes and highlight the advantage of metagenomics in detection of novel microbial key players. © 2017 The Authors. MicrobiologyOpen published by John Wiley & Sons Ltd.

  9. From vineyard to winery: a source map of microbial diversity driving wine fermentation.

    Science.gov (United States)

    Morrison-Whittle, Peter; Goddard, Matthew R

    2018-01-01

    Humans have been making wine for thousands of years and microorganisms play an integral part in this process as they not only drive fermentation, but also significantly influence the flavour, aroma and quality of finished wines. Since fruits are ephemeral, they cannot comprise a permanent microbial habitat; thus, an age-old unanswered question concerns the origin of fruit and ferment associated microbes. Here we use next-generation sequencing approaches to examine and quantify the roles of native forest, vineyard soil, bark and fruit habitats as sources of fungal diversity in ferments. We show that microbial communities in harvested juice and ferments vary significantly across regions, and that while vineyard fungi account for ∼40% of the source of this diversity, uncultivated ecosystems outside of vineyards also prove a significant source. We also show that while communities in harvested juice resemble those found on grapes, these increasingly resemble fungi present on vine bark as the ferment proceeds. © 2017 The Authors. Environmental Microbiology published by Society for Applied Microbiology and John Wiley & Sons Ltd.

  10. Out of the shadows : multiple nutrient limitations drive relationships among biomass, light and plant diversity

    NARCIS (Netherlands)

    Harpole, W. Stanley; Sullivan, Lauren L.; Lind, Eric M.; Firn, Jennifer; Adler, Peter B.; Borer, Elizabeth T.; Chase, Jonathan; Fay Jennifer Firn, Philip A.; Hautier, Yann; Hillebrand, Helmut; MacDougall, Andrew S.; Seabloom, Eric W.; Bakker, Jonathan D.; Cadotte, Marc W; Chaneton, Enrique J; Chu, Chengjin; Hagenah, Nicole; Kirkman, Kevin; La Pierre, Kimberly J.; Moore, Joslin L.; Morgan, John W.; Prober, Suzanne M.; Risch, Anita C.; Schuetz, Martin; Stevens, Carly J.

    2017-01-01

    The paradigmatic hypothesis for the effect of fertilisation on plant diversity represents a one-dimensional trade-off for plants competing for below-ground nutrients (generically) and above-ground light: fertilisation reduces competition for nutrients while increasing biomass and thereby shifts

  11. Effects of chewing gum on driving performance as evaluated by the STISIM driving simulator.

    Science.gov (United States)

    Yoo, Ingyu; Kim, Eun-Joo; Lee, Joo-Hyun

    2015-06-01

    [Purpose] The purpose of this study was to determine the effects of chewing gum on driving performance in a driving simulator. [Subjects] In total, 26 young licensed drivers participated. [Methods] The driving scenario was typical of an urban environment: a single-carriageway, two-way road consisting of a mix of curved and straight sections, with considerable levels of traffic, pedestrians, and parked cars. Mean distance driven above the speed limit, lane position, mean distance driven across the center line, and mean distance driven off the road were used as estimates of brake, accelerator, and steering control. The results were compared with those of a non-chewing gum control condition. [Results] The driving performance while chewing gum was significantly better: the mean distance driven above the speed limit was 26.61% shorter, and the mean distance driven off the road was 31.99% shorter. Lane position and mean distance driven across the center line did not differ significantly between the two conditions. [Conclusion] Chewing gum appears to enhance driving performance during a sustained attention driving task.

  12. THE EFFECT OF CELLULAR PHONE USE ON DRIVING PERFORMANCE

    Directory of Open Access Journals (Sweden)

    Toshiro ISHIDA

    2001-01-01

    In this experiment, it was confirmed that use of a hands-free set is effective to some extent, but driving performance was poorer than with driving only. Even though different forms of in-vehicle information apparatus were used, a delay in information processing was consistently found.

  13. Drowsiness in conditional automation : Proneness, diagnosis and driving performance effects

    NARCIS (Netherlands)

    Goncalves, J.; Happee, R.; Bengler, KJ; Rosetti, R.; Wolf, D.

    2016-01-01

    Fatigue and drowsiness can play an important role in Conditional Automation (CA), as drowsy drivers may fail to properly recover control. In order to provide better insight in the effects of drowsy driving in Take Over Request (TOR), we designed a driving experiment that extends related

  14. Two decades of climate driving the dynamics of functional and taxonomic diversity of a tropical small mammal community in western Mexico.

    Science.gov (United States)

    Mason-Romo, Edgard David; Farías, Ariel A; Ceballos, Gerardo

    2017-01-01

    Understanding the effects of global climate disruption on biodiversity is important to future conservation efforts. While taxonomic diversity is widely studied, functional diversity of plants, and recently animals, is receiving increasing attention. Most studies of mammals are short-term, focus on temperate habitats, and rely on traits described in the literature rather than generating traits from observations. Unlike previous studies, this long-term field study assessed the factors driving the functional and taxonomic diversity of small-mammal assemblages in dry tropical forests using both traits recorded from literature and a demographic database. We assessed the drivers (abundance and biomass, temperature and rainfall) of taxonomic richness and functional diversity for two rain-driven seasons in two adjacent but distinct forests-upland and lowland (arroyo or riparian) forests. Our analysis found that rainfall, both seasonal and atypical, was the primary factor driving functional and taxonomic diversity of small-mammal assemblages. Functional responses differed between the two types of forests, however, with effects being stronger in the harsher conditions of the upland forests than in the less severe conditions prevailing in the arroyo (riparian) forest. The latter also supports a richer, more diverse, and more stable small-mammal assemblage. These findings highlight the importance of climate to tropical biological diversity, as extreme climate events (hurricanes, droughts and floods) and disruption of rainfall patterns were shown to decrease biodiversity. They also support the need to preserve these habitats, as their high taxonomic diversity and functional redundancy makes them resilient against global climate disruption and local extreme events. Tropical dry forests constitute a potential reservoir for biodiversity and the ecosystem services they provide. Unfortunately, these forests are among the most endangered terrestrial ecosystems because of

  15. Two decades of climate driving the dynamics of functional and taxonomic diversity of a tropical small mammal community in western Mexico.

    Directory of Open Access Journals (Sweden)

    Edgard David Mason-Romo

    Full Text Available Understanding the effects of global climate disruption on biodiversity is important to future conservation efforts. While taxonomic diversity is widely studied, functional diversity of plants, and recently animals, is receiving increasing attention. Most studies of mammals are short-term, focus on temperate habitats, and rely on traits described in the literature rather than generating traits from observations. Unlike previous studies, this long-term field study assessed the factors driving the functional and taxonomic diversity of small-mammal assemblages in dry tropical forests using both traits recorded from literature and a demographic database. We assessed the drivers (abundance and biomass, temperature and rainfall of taxonomic richness and functional diversity for two rain-driven seasons in two adjacent but distinct forests-upland and lowland (arroyo or riparian forests. Our analysis found that rainfall, both seasonal and atypical, was the primary factor driving functional and taxonomic diversity of small-mammal assemblages. Functional responses differed between the two types of forests, however, with effects being stronger in the harsher conditions of the upland forests than in the less severe conditions prevailing in the arroyo (riparian forest. The latter also supports a richer, more diverse, and more stable small-mammal assemblage. These findings highlight the importance of climate to tropical biological diversity, as extreme climate events (hurricanes, droughts and floods and disruption of rainfall patterns were shown to decrease biodiversity. They also support the need to preserve these habitats, as their high taxonomic diversity and functional redundancy makes them resilient against global climate disruption and local extreme events. Tropical dry forests constitute a potential reservoir for biodiversity and the ecosystem services they provide. Unfortunately, these forests are among the most endangered terrestrial ecosystems because

  16. Effects of upper-limb immobilisation on driving safety.

    Science.gov (United States)

    Gregory, J J; Stephens, A N; Steele, N A; Groeger, J A

    2009-03-01

    Doctors are frequently asked by patients whether it is safe to drive with an upper limb immobilised in a cast. In the literature there are no objective measurements of the effects of upper-limb immobilisation upon driving performance. Eight healthy volunteers performed four 20-min driving circuits in a driving simulator (STISIM 400W), circuits 1 and 4 without immobilisation and circuits 2 and 3 with immobilisation. Immobilisation involved a lightweight below-elbow cast with the thumb left free. Volunteers were randomised to right or left immobilisation for circuit 2, and the contralateral wrist was immobilised for circuit 3. Circuits included urban and rural environments and specific hazards (pedestrians crossing, vehicles emerging from a concealed entrance, traffic lights changing suddenly, avoidance of an oncoming vehicle in the driver's carriageway). Limb immobilisation led to more cautious rural and urban driving, with less adjustment of speed and lateral road position than when unrestricted. However when responding to hazards immobilisation caused less safe driving, with higher speeds, a greater proximity to the hazard before action was taken and less steering adjustment. The effects of restriction upon performance were more prevalent and severe with right-arm immobilisation. Upper-limb immobilisation appears to have little effect on the ability to drive a car unchallenged, but to adversely affect responses to routine hazards. Advice on ability to drive safely should be cautious, as the impact of immobilisation appears to be more subtle and wide ranging than previously thought.

  17. Resource diversity and landscape-level homogeneity drive native bee foraging.

    Science.gov (United States)

    Jha, Shalene; Kremen, Claire

    2013-01-08

    Given widespread declines in pollinator communities and increasing global reliance on pollinator-dependent crops, there is an acute need to develop a mechanistic understanding of native pollinator population and foraging biology. Using a population genetics approach, we determine the impact of habitat and floral resource distributions on nesting and foraging patterns of a critical native pollinator, Bombus vosnesenskii. Our findings demonstrate that native bee foraging is far more plastic and extensive than previously believed and does not follow a simple optimal foraging strategy. Rather, bumble bees forage further in pursuit of species-rich floral patches and in landscapes where patch-to-patch variation in floral resources is less, regardless of habitat composition. Thus, our results reveal extreme foraging plasticity and demonstrate that floral diversity, not density, drives bee foraging distance. Furthermore, we find a negative impact of paved habitat and a positive impact of natural woodland on bumble bee nesting densities. Overall, this study reveals that natural and human-altered landscapes can be managed for increased native bee nesting and extended foraging, dually enhancing biodiversity and the spatial extent of pollination services.

  18. The effects of texting on driving performance in a driving simulator: the influence of driver age.

    Science.gov (United States)

    Rumschlag, Gordon; Palumbo, Theresa; Martin, Amber; Head, Doreen; George, Rajiv; Commissaris, Randall L

    2015-01-01

    Distracted driving is a significant contributor to motor vehicle accidents and fatalities, and texting is a particularly significant form of driver distraction that continues to be on the rise. The present study examined the influence of driver age (18-59 years old) and other factors on the disruptive effects of texting on simulated driving behavior. While 'driving' the simulator, subjects were engaged in a series of brief text conversations with a member of the research team. The primary dependent variable was the occurrence of Lane Excursions (defined as any time the center of the vehicle moved outside the directed driving lane, e.g., into the lane for oncoming traffic or onto the shoulder of the road), measured as (1) the percent of subjects that exhibited Lane Excursions, (2) the number of Lane Excursions occurring and (3) the percent of the texting time in Lane Excursions. Multiple Regression analyses were used to assess the influence of several factors on driving performance while texting, including text task duration, texting skill level (subject-reported), texting history (#texts/week), driver gender and driver age. Lane Excursions were not observed in the absence of texting, but 66% of subjects overall exhibited Lane Excursions while texting. Multiple Regression analysis for all subjects (N=50) revealed that text task duration was significantly correlated with the number of Lane Excursions, and texting skill level and driver age were significantly correlated with the percent of subjects exhibiting Lane Excursions. Driver gender was not significantly correlated with Lane Excursions during texting. Multiple Regression analysis of only highly skilled texters (N=27) revealed that driver age was significantly correlated with the number of Lane Excursions, the percent of subjects exhibiting Lane Excursions and the percent of texting time in Lane Excursions. In contrast, Multiple Regression analysis of those drivers who self-identified as not highly skilled

  19. Alcohol use and drunk driving: the modifying effect of impulsivity.

    Science.gov (United States)

    Moan, Inger Synnøve; Norström, Thor; Storvoll, Elisabet E

    2013-01-01

    The aim of this study was twofold: (a) to examine how an increase in the frequency of heavy drinking episodes affects the incidence of drunk driving and (b) to examine whether the effect of alcohol use on drunk driving is contingent on impulsivity. Two waves of the Young in Norway Longitudinal Study were applied (N = 2,603; response rate: 67%), when the respondents were on average 17 (1994) and 28 (2005) years of age. Measurements consisted of self-reported heavy episodic drinking, drunk driving, and impulsivity. The first difference method was applied to estimate the association between heavy episodic drinking and drunk driving. This means that changes in the frequency of drunk driving were regressed on changes in the frequency of drinking. In this way, the effects of time-invariant confounders were eliminated. The results showed that every additional episode of heavy drinking was associated with a 2.6% increase in the frequency of drunk driving. The increase for males was significantly higher than among females. The analyses supported the hypothesis that impulsivity modifies the association between alcohol use and drunk driving. The association between drinking and drunk driving is significantly stronger among those with a high score on impulsivity compared with those who have a low score.

  20. Climatic changes can drive the loss of genetic diversity in a Neotropical savanna tree species.

    Science.gov (United States)

    Lima, Jacqueline S; Ballesteros-Mejia, Liliana; Lima-Ribeiro, Matheus S; Collevatti, Rosane G

    2017-11-01

    The high rates of future climatic changes, compared with the rates reported for past changes, may hamper species adaptation to new climates or the tracking of suitable conditions, resulting in significant loss of genetic diversity. Trees are dominant species in many biomes and because they are long-lived, they may not be able to cope with ongoing climatic changes. Here, we coupled ecological niche modelling (ENM) and genetic simulations to forecast the effects of climatic changes on the genetic diversity and the structure of genetic clusters. Genetic simulations were conditioned to climatic variables and restricted to plant dispersal and establishment. We used a Neotropical savanna tree as species model that shows a preference for hot and drier climates, but with low temperature seasonality. The ENM predicts a decreasing range size along the more severe future climatic scenario. Additionally, genetic diversity and allelic richness also decrease with range retraction and climatic genetic clusters are lost for both future scenarios, which will lead genetic variability to homogenize throughout the landscape. Besides, climatic genetic clusters will spatially reconfigure on the landscape following displacements of climatic conditions. Our findings indicate that climate change effects will challenge population adaptation to new environmental conditions because of the displacement of genetic ancestry clusters from their optimal conditions. © 2017 John Wiley & Sons Ltd.

  1. The effect of social marketing communication on safe driving.

    Science.gov (United States)

    Yang, Dong-Jenn; Lin, Wan-Chen; Lo, Jyue-Yu

    2011-12-01

    Processing of cognition, affect, and intention was investigated in viewers of advertisements to prevent speeding while driving. Results indicated that anchoring-point messages had greater effects on viewers' cognition, attitude, and behavioral intention than did messages without anchoring points. Further, the changes in message anchoring points altered participants' perceptions of acceptable and unacceptable judgments: a higher anchoring point in the form of speeding mortality was more persuasive in promoting the idea of reducing driving speed. Implications for creation of effective safe driving communications are discussed.

  2. The Effects of Medical Conditions on Driving Performance

    Science.gov (United States)

    2017-08-01

    This project investigated the effect of selected medical conditions on the exposure and performance of older drivers. A review of recent literature, followed by a panel meeting with driving safety experts, prioritized four medical conditions for furt...

  3. Effectiveness of Variable Message Signs on Driving Behavior Based on a Driving Simulation Experiment

    Directory of Open Access Journals (Sweden)

    Xuedong Yan

    2014-01-01

    Full Text Available Variable message signs (VMSs, as one of the important ITS devices, provide real-time traffic information of road network to drivers in order to improve route choice and relieve the traffic congestion. In this study, the effectiveness of VMS on driving behavior was tested based on a driving simulation experiment. A road network with three levels of VMS location to route-diverging intersection and three types of VMS information format was designed in a high fidelity driving simulator platform. Fifty-two subjects who were classified by driver age, gender, and vocation successfully completed this experiment. The experimental results showed that driver characteristics, VMS location, and information format profoundly influence driving behaviors. Based on the research findings, it is suggested that VMS would be positioned between 150 m and 200 m upstream of the diverging point to balance the VMS effects on traffic safety and operation and the graphic information VMS format is better than the format with text massage only.

  4. Urbanization Drives a Reduction in Functional Diversity in a Guild of Nectar-feeding Birds

    Directory of Open Access Journals (Sweden)

    Anton Pauw

    2012-06-01

    Full Text Available Urbanization is a widespread and rapidly growing threat to biodiversity, therefore we need a predictive understanding of its effects on species and ecosystem processes. In this paper we study the impact of urbanization on a guild of nectar-feeding birds in a biodiversity hotspot at the Cape of Africa. The guild of four bird species provides important ecosystem services by pollinating 320 plant species in the Cape Floral Region. Functional diversity within the guild is related to differences in bill length. The long-billed Malachite Sunbird (Nectarinia famosa plays an irreplaceable role as the exclusive pollinator of plant species with long nectar tubes. We analyzed the composition of the guild in suburban gardens of Cape Town along a gradient of increasing distance from the nearest natural habitat. Urbanization reduces the functional diversity of the nectarivore guild. Malachite Sunbirds did not penetrate more than 1 km into the city, whereas only the short-billed Southern Double-collared Sunbirds (Cinnyris chalybea occurred throughout the urbanization gradient. The lack of data precludes conclusions regarding the detailed responses of Orange-breasted Sunbirds (Anthobaphes violacea and Sugarbirds (Promerops cafer, however their absence across the entire gradient is suggestive of high sensitivity. The functional diversity of this guild of pollinators can potentially be restored, but the pros and cons of this conservation action need to be considered.

  5. Ontogenetic functional diversity: size structure of a keystone predator drives functioning of a complex ecosystem.

    Science.gov (United States)

    Rudolf, Volker H W; Rasmussen, Nick L

    2013-05-01

    A central challenge in community ecology is to understand the connection between biodiversity and the functioning of ecosystems. While traditional approaches have largely focused on species-level diversity, increasing evidence indicates that there exists substantial ecological diversity among individuals within species. By far, the largest source of this intraspecific diversity stems from variation among individuals in ontogenetic stage and size. Although such ontogenetic shifts are ubiquitous in natural communities, whether and how they scale up to influence the structure and functioning of complex ecosystems is largely unknown. Here we take an experimental approach to examine the consequences of ontogenetic niche shifts for the structure of communities and ecosystem processes. In particular we experimentally manipulated the stage structure in a keystone predator, larvae of the dragonfly Anax junius, in complex experimental pond communities to test whether changes in the population stage or size structure of a keystone species scale up to alter community structure and ecosystem processes, and how functional differences scale with relative differences in size among stages. We found that the functional role of A. junius was stage-specific. Altering what stages were present in a pond led to concurrent changes in community structure, primary producer biomass (periphyton and phytoplankton), and ultimately altered ecosystem processes (respiration and net primary productivity), indicating a strong, but stage-specific, trophic cascade. Interestingly, the stage-specific effects did not simply scale with size or biomass of the predator, but instead indicated clear ontogenetic niche shifts in ecological interactions. Thus, functional differences among stages within a keystone species scaled up to alter the functioning of entire ecosystems. Therefore, our results indicate that the classical approach of assuming an average functional role of a species can be misleading because

  6. The effects of below-elbow immobilization on driving performance.

    Science.gov (United States)

    Jones, Evan M; Barrow, Aaron E; Skordas, Nic J; Green, David P; Cho, Mickey S

    2017-02-01

    There is limited research to guide physicians and patients in deciding whether it is safe to drive while wearing various forms of upper extremity immobilization. The purpose of this study is to evaluate the effect of below-elbow removable splints and fiberglass casts on automobile driving performance. 20 healthy subjects completed 10 runs through a closed, cone-marked driving course while wearing a randomized sequence of four different types of immobilization on each extremity (short arm thumb spica fiberglass cast, short arm fiberglass cast, short arm thumb spica splint, and short arm wrist splint). The first and last driving runs were without immobilization and served as controls. Performance was measured based on evaluation by a certified driving instructor (pass/fail scoring), cones hit, run time, and subject-perceived driving difficulty (1-10 analogue scoring). The greatest number of instructor-scored failures occurred while immobilized in right arm spica casts (n=6; p=0.02) and left arm spica casts (n=5; p=0.049). The right arm spica cast had the highest subject-perceived difficulty (5.2±1.9; pimmobilization had significantly increased perceived difficulty compared to control, except for the left short arm splint (2.5±1.6; p>0.05). There was no significant difference in number of cones hit or driving time between control runs and runs with any type of immobilization. Drivers should use caution when wearing any of the forms of upper extremity immobilization tested in this study. All forms of immobilization, with exception of the left short arm splint significantly increased perceived driving difficulty. However, only the fiberglass spica casts (both left and right arm), significantly increased drive run failures due to loss of vehicle control. We recommend against driving when wearing a below-elbow fiberglass spica cast on either extremity. Copyright © 2016. Published by Elsevier Ltd.

  7. Effect of Functional diversity on Software Performance

    OpenAIRE

    Viswanatha Rao, Balajee

    2011-01-01

    For the past few decades, there has been numerous literature produced on functional diversity and performance. However, the relationship between functional diversity and performance in software industry is clearly not explained and results are found to be inconsistent. The main focus of this research is to explore the effects of functional diversity on software project performance by conducting a qualitative study. Four metrics were chosen from literature namely decision making, creativity an...

  8. Neoclassical effects on RF current drive in tokamaks

    International Nuclear Information System (INIS)

    Yoshioka, K.; Antonsen, T.M. Jr.

    1986-01-01

    Neoclassical effects on RF current drive which arise because of the inhomogeneity of the magnetic field in tokamak devices are analysed. A bounce averaged 2-D Fokker-Planck equation is derived from the drift kinetic equation and is solved numerically. The model features current drive due to a strong RF wave field. The efficiency of current drive by electron cyclotron waves is significantly reduced when the waves are absorbed at the low magnetic field side of a given flux surface, whereas the efficiency remains at the same level as in the homogeneous ideal plasma when the waves are absorbed at the high field side. The efficiency of current drive by fast waves (compressional Alfven waves) with low phase velocity (vsub(parallel)/vsub(th)<1) is significantly degraded by neoclassical effects, no matter where the wave is absorbed, and the applicability of this wave seems, therefore, to be doubtful. (author)

  9. Landscape heritage objects' effect on driving: a combined driving simulator and questionnaire study.

    Science.gov (United States)

    Antonson, Hans; Ahlström, Christer; Mårdh, Selina; Blomqvist, Göran; Wiklund, Mats

    2014-01-01

    According to the literature, landscape (panoramas, heritage objects e.g. landmarks) affects people in various ways. Data are primarily developed by asking people (interviews, photo sessions, focus groups) about their preferences, but to a lesser degree by measuring how the body reacts to such objects. Personal experience while driving a car through a landscape is even more rare. In this paper we study how different types of objects in the landscape affect drivers during their drive. A high-fidelity moving-base driving simulator was used to measure choice of speed and lateral position in combination with stress (heart rate measure) and eye tracking. The data were supplemented with questionnaires. Eighteen test drivers (8 men and 10 women) with a mean age of 37 were recruited. The test drivers were exposed to different new and old types of landscape objects such as 19th century church, wind turbine, 17th century milestone and bus stop, placed at different distances from the road driven. The findings are in some respect contradictory, but it was concluded that that 33% of the test drivers felt stressed during the drive. All test drivers said that they had felt calm at times during the drive but the reason for this was only to a minor degree connected with old and modern objects. The open landscape was experienced as conducive to acceleration. Most objects were, to a small degree, experienced (subjective data) as having a speed-reducing effect, much in line with the simulator data (objective data). Objects close to the road affected the drivers' choice of' lateral position. No significant differences could be observed concerning the test drivers' gaze between old or modern objects, but a significant difference was observed between the test drivers' gaze between road stretches with faraway objects and stretches without objects. No meaningful, significant differences were found for the drivers' stress levels as measured by heart rate. Copyright © 2013 Elsevier Ltd. All

  10. Effects of Non-Driving Related Task Modalities on Takeover Performance in Highly Automated Driving.

    Science.gov (United States)

    Wandtner, Bernhard; Schömig, Nadja; Schmidt, Gerald

    2018-04-01

    Aim of the study was to evaluate the impact of different non-driving related tasks (NDR tasks) on takeover performance in highly automated driving. During highly automated driving, it is allowed to engage in NDR tasks temporarily. However, drivers must be able to take over control when reaching a system limit. There is evidence that the type of NDR task has an impact on takeover performance, but little is known about the specific task characteristics that account for performance decrements. Thirty participants drove in a simulator using a highly automated driving system. Each participant faced five critical takeover situations. Based on assumptions of Wickens's multiple resource theory, stimulus and response modalities of a prototypical NDR task were systematically manipulated. Additionally, in one experimental group, the task was locked out simultaneously with the takeover request. Task modalities had significant effects on several measures of takeover performance. A visual-manual texting task degraded performance the most, particularly when performed handheld. In contrast, takeover performance with an auditory-vocal task was comparable to a baseline without any task. Task lockout was associated with faster hands-on-wheel times but not altered brake response times. Results showed that NDR task modalities are relevant factors for takeover performance. An NDR task lockout was highly accepted by the drivers and showed moderate benefits for the first takeover reaction. Knowledge about the impact of NDR task characteristics is an enabler for adaptive takeover concepts. In addition, it might help regulators to make decisions on allowed NDR tasks during automated driving.

  11. Changes in agricultural management drive the diversity of Burkholderia species isolated from soil on PLAT medium

    NARCIS (Netherlands)

    Salles, JF; Samyn, E; Vandamme, P; van Veen, JA; van Elsas, JD

    In order to assess the diversity of culturable Burkholderia populations in rhizosphere and bulk soil and to evaluate how different agricultural management regimes and land use history affect this diversity, four treatments were evaluated: permanent grassland; grassland converted into maize

  12. Changes in agricultural management drive the diversity of Burkholderia species isolated from soil on PCAT medium

    NARCIS (Netherlands)

    Salles, J.F.; Samyn, E.; Vandamme, P.A.; Veen, van J.A.; Elsas, van J.D.

    2006-01-01

    In order to assess the diversity of culturable Burkholderia populations in rhizosphere and bulk soil and to evaluate how different agricultural management regimes and land use history affect this diversity, four treatments were evaluated: permanent grassland; grassland converted into maize

  13. Recombination Is a Major Driving Force of Genetic Diversity in the Anaplasmataceae Ehrlichia ruminantium.

    Science.gov (United States)

    Cangi, Nídia; Gordon, Jonathan L; Bournez, Laure; Pinarello, Valérie; Aprelon, Rosalie; Huber, Karine; Lefrançois, Thierry; Neves, Luís; Meyer, Damien F; Vachiéry, Nathalie

    2016-01-01

    The disease, Heartwater, caused by the Anaplasmataceae E. ruminantium , represents a major problem for tropical livestock and wild ruminants. Up to now, no effective vaccine has been available due to a limited cross protection of vaccinal strains on field strains and a high genetic diversity of Ehrlichia ruminantium within geographical locations. To address this issue, we inferred the genetic diversity and population structure of 194 E. ruminantium isolates circulating worldwide using Multilocus Sequence Typing based on lipA, lipB, secY, sodB , and sucA genes . Phylogenetic trees and networks were generated using BEAST and SplitsTree, respectively, and recombination between the different genetic groups was tested using the PHI test for recombination. Our study reveals the repeated occurrence of recombination between E. ruminantium strains, suggesting that it may occur frequently in the genome and has likely played an important role in the maintenance of genetic diversity and the evolution of E. ruminantium . Despite the unclear phylogeny and phylogeography, E. ruminantium isolates are clustered into two main groups: Group 1 (West Africa) and a Group 2 (worldwide) which is represented by West, East, and Southern Africa, Indian Ocean, and Caribbean strains. Some sequence types are common between West Africa and Caribbean and between Southern Africa and Indian Ocean strains. These common sequence types highlight two main introduction events due to the movement of cattle: from West Africa to Caribbean and from Southern Africa to the Indian Ocean islands. Due to the long branch lengths between Group 1 and Group 2, and the propensity for recombination between these groups, it seems that the West African clusters of Subgroup 2 arrived there more recently than the original divergence of the two groups, possibly with the original waves of domesticated ruminants that spread across the African continent several thousand years ago.

  14. Green Eco-Driving Effects in Non-Congested Cities

    Directory of Open Access Journals (Sweden)

    Juan Francisco Coloma

    2017-12-01

    Full Text Available Despite technological advances in engines and fuels, the transportation sector is still one of the largest emitters of greenhouse gas (GHG. Driving patterns, including eco-driving techniques, are a complementary measure for saving GHG emissions. Most eco-driving studies so far have been conducted in large cities suffering chronic congestion problems. The aim of this research is therefore to analyse the potential of driver behaviour for reducing emissions in a small non-congested city. Driver performance parameters such as travel speeds, number of stops, revolutions per minute, and maximum acceleration-deceleration are also studied. The methodology is designed to measure the effect of both eco-driving and eco-routing under real traffic conditions. A campaign was carried out in the city of Caceres (Spain to collect data on various types of roads under different traffic conditions. This research concludes that eco-driving leads to CO2 savings on all routes and road types of 17% in gasoline engines and 21% in diesel, although travel times are increased by 7.5% on average. The shortest route is also the most ecological, regardless of the traffic volume and characteristics, implying that consumption in non-congested cities depends mainly on distance travelled rather than driving patterns in terms of number of stops, speed and acceleration.

  15. Manual control analysis of drug effects on driving performance

    Science.gov (United States)

    Smiley, A.; Ziedman, K.; Moskowitz, H.

    1981-01-01

    The effects of secobarbital, diazepam, alcohol, and marihuana on car-driver transfer functions obtained using a driving simulator were studied. The first three substances, all CNS depressants, reduced gain, crossover frequency, and coherence which resulted in poorer tracking performance. Marihuana also impaired tracking performance but the only effect on the transfer function parameters was to reduce coherence.

  16. Geomorphology Drives Amphibian Beta Diversity in Atlantic Forest Lowlands of Southeastern Brazil

    OpenAIRE

    Luiz, Amom Mendes; Le?o-Pires, Thiago Augusto; Sawaya, Ricardo J.

    2016-01-01

    Beta diversity patterns are the outcome of multiple processes operating at different scales. Amphibian assemblages seem to be affected by contemporary climate and dispersal-based processes. However, historical processes involved in present patterns of beta diversity remain poorly understood. We assess and disentangle geomorphological, climatic and spatial drivers of amphibian beta diversity in coastal lowlands of the Atlantic Forest, southeastern Brazil. We tested the hypothesis that geomorph...

  17. Novel oligonucleotide primers reveal a high diversity of microbes which drive phosphorous turnover in soil.

    Science.gov (United States)

    Bergkemper, Fabian; Kublik, Susanne; Lang, Friederike; Krüger, Jaane; Vestergaard, Gisle; Schloter, Michael; Schulz, Stefanie

    2016-06-01

    Phosphorus (P) is of central importance for cellular life but likewise a limiting macronutrient in numerous environments. Certainly microorganisms have proven their ability to increase the phosphorus bioavailability by mineralization of organic-P and solubilization of inorganic-P. On the other hand they efficiently take up P and compete with other biota for phosphorus. However the actual microbial community that is associated to the turnover of this crucial macronutrient in different ecosystems remains largely anonymous especially taking effects of seasonality and spatial heterogeneity into account. In this study seven oligonucleotide primers are presented which target genes coding for microbial acid and alkaline phosphatases (phoN, phoD), phytases (appA), phosphonatases (phnX) as well as the quinoprotein glucose dehydrogenase (gcd) and different P transporters (pitA, pstS). Illumina amplicon sequencing of soil genomic DNA underlined the high rate of primer specificity towards the respective target gene which usually ranged between 98% and 100% (phoN: 87%). As expected the primers amplified genes from a broad diversity of distinct microorganisms. Using DNA from a beech dominated forest soil, the highest microbial diversity was detected for the alkaline phosphatase (phoD) gene which was amplified from 15 distinct phyla respectively 81 families. Noteworthy the primers also allowed amplification of phoD from 6 fungal orders. The genes coding for acid phosphatase (phoN) and the quinoprotein glucose dehydrogenase (gcd) were amplified from 20 respectively 17 different microbial orders. In comparison the phytase and phosphonatase (appA, phnX) primers covered 13 bacterial orders from 2 different phyla respectively. Although the amplified microbial diversity was apparently limited both primers reliably detected all orders that contributed to the P turnover in the investigated soil as revealed by a previous metagenomic approach. Genes that code for microbial P transporter

  18. The effect of cannabis compared with alcohol on driving.

    Science.gov (United States)

    Sewell, R Andrew; Poling, James; Sofuoglu, Mehmet

    2009-01-01

    The prevalence of both alcohol and cannabis use and the high morbidity associated with motor vehicle crashes has lead to a plethora of research on the link between the two. Drunk drivers are involved in 25% of motor vehicle fatalities, and many accidents involve drivers who test positive for cannabis. Cannabis and alcohol acutely impair several driving-related skills in a dose-related fashion, but the effects of cannabis vary more between individuals than they do with alcohol because of tolerance, differences in smoking technique, and different absorptions of Delta(9)-tetrahydrocannabinol (THC), the active ingredient in marijuana. Detrimental effects of cannabis use vary in a dose-related fashion, and are more pronounced with highly automatic driving functions than with more complex tasks that require conscious control, whereas alcohol produces an opposite pattern of impairment. Because of both this and an increased awareness that they are impaired, marijuana smokers tend to compensate effectively while driving by utilizing a variety of behavioral strategies. Combining marijuana with alcohol eliminates the ability to use such strategies effectively, however, and results in impairment even at doses which would be insignificant were they of either drug alone. Epidemiological studies have been inconclusive regarding whether cannabis use causes an increased risk of accidents; in contrast, unanimity exists that alcohol use increases crash risk. Furthermore, the risk from driving under the influence of both alcohol and cannabis is greater than the risk of driving under the influence of either alone. Future research should focus on resolving contradictions posed by previous studies, and patients who smoke cannabis should be counseled to wait several hours before driving, and avoid combining the two drugs.

  19. Changes in agricultural management drive the diversity of Burkholderia species isolated from soil on PCAT medium

    NARCIS (Netherlands)

    Salles, Joanna; Samyn, E.; Vandamme, P.; Van Veen, J.A.; van Elsas, J.D.

    2006-01-01

    Abstract In order to assess the diversity of culturable Burkholderia populations in rhizosphere and bulk soil and to evaluate how different agricultural management regimes and land use history affect this diversity, four treatments were evaluated: permanent grassland; grassland converted into maize

  20. Direct electromechanical driving systems: diversity, constraints and solutions; Les entrainements electromecaniques directs: diversite, contraintes et solutions

    Energy Technology Data Exchange (ETDEWEB)

    Multon, B. [Ecole Normale Superieure, 94 - Cachan (France); Bonal, J. [Promethee Groupe Schneider Electric S.A., 92 - Boulogne-Billancourt (France)

    1999-11-01

    Direct electromechanical drives are the simplest possible transmission systems requiring no additional mechanical components such as gearboxes or rotary to linear converters. This simplicity leads a number of advantages including greater reliability, less maintenance, improved dynamic characteristics and reduced weight and volume. However, the performance specification of direct drives is usually high, with a correspondingly high cost, and often this cannot be justified in complete systems where the other components limit the overall performance. This factor alone has been sufficient to restrict the market penetration of direct drives. The majority of applications are in linear actuators, and in motors operating at very high or very low speeds. New developments are constantly being introduced, especially in relation to structures.

  1. Changes in species diversity of arboreal spiders in Mexican coffee agroecosystems: untangling the web of local and landscape influences driving diversity

    Directory of Open Access Journals (Sweden)

    Zachary Hajian-Forooshani

    2014-11-01

    Full Text Available Agricultural intensification is implicated as a major driver of global biodiversity loss. Local management and landscape scale factors both influence biodiversity in agricultural systems, but there are relatively few studies to date looking at how local and landscape scales influence biodiversity in tropical agroecosystems. Understanding what drives the diversity of groups of organisms such as spiders is important from a pragmatic point of view because of the important biocontrol services they offer to agriculture. Spiders in coffee are somewhat enigmatic because of their positive or lack of response to agricultural intensification. In this study, we provide the first analysis, to our knowledge, of the arboreal spiders in the shade trees of coffee plantations. In the Soconusco region of Chiapas, Mexico we sampled across 38 sites on 9 coffee plantations. Tree and canopy connectedness were found to positively influence overall arboreal spider richness and abundance. We found that different functional groups of spiders are responding to different local and landscape factors, but overall elevation was most important variable influencing arboreal spider diversity. Our study has practical management applications that suggest having shade grown coffee offers more suitable habitat for arboreal spiders due to a variety of the characteristics of the shade trees. Our results which show consistently more diverse arboreal spider communities in lower elevations are important in light of looming global climate change. As the range of suitable elevations for coffee cultivation shrinks promoting arboreal spider diversity will be important in sustaining the viability of coffee.

  2. THE EFFECTS OF MOBILE TELEPHONING ON DRIVING PERFORMANCE

    NARCIS (Netherlands)

    BROOKHUIS, KA; DEVRIES, G; DEWAARD, D

    The effects of telephoning while driving were studied in three different traffic conditions, i.e. in light traffic on a quiet motorway, in heavy traffic on a four-lane ring-road, and in city traffic. Twelve subjects, unfamiliar with mobile telephones, drove an instrumented vehicle for one hour each

  3. Stabilizing effect of driving and dissipation on quantum metastable states

    Science.gov (United States)

    Valenti, Davide; Carollo, Angelo; Spagnolo, Bernardo

    2018-04-01

    We investigate how the combined effects of strong Ohmic dissipation and monochromatic driving affect the stability of a quantum system with a metastable state. We find that, by increasing the coupling with the environment, the escape time makes a transition from a regime in which it is substantially controlled by the driving, displaying resonant peaks and dips, to a regime of frequency-independent escape time with a peak followed by a steep falloff. The escape time from the metastable state has a nonmonotonic behavior as a function of the thermal-bath coupling, the temperature, and the frequency of the driving. The quantum noise-enhanced stability phenomenon is observed in the investigated system.

  4. Perception of the Risks Associated with Impaired Driving and Effects on Driving Behavior

    OpenAIRE

    Georges Dionne; Claude Fluet; Denise Desjardins

    2006-01-01

    This research studies the perception of the risks associated with impaired driving-probability of being apprehended or of having an accident-and the relation between the perception of risks and driving behavior. The most important determinants of perceptual biases are age, an accumulation of violations in the year preceding the survey, being a non-drinker, knowledge of the legal alcohol limit for driving, opinion about zero tolerance for impaired driving, and family income. Perceptual biases ...

  5. Geomorphology Drives Amphibian Beta Diversity in Atlantic Forest Lowlands of Southeastern Brazil.

    Directory of Open Access Journals (Sweden)

    Amom Mendes Luiz

    Full Text Available Beta diversity patterns are the outcome of multiple processes operating at different scales. Amphibian assemblages seem to be affected by contemporary climate and dispersal-based processes. However, historical processes involved in present patterns of beta diversity remain poorly understood. We assess and disentangle geomorphological, climatic and spatial drivers of amphibian beta diversity in coastal lowlands of the Atlantic Forest, southeastern Brazil. We tested the hypothesis that geomorphological factors are more important in structuring anuran beta diversity than climatic and spatial factors. We obtained species composition via field survey (N = 766 individuals, museum specimens (N = 9,730 and literature records (N = 4,763. Sampling area was divided in four spatially explicit geomorphological units, representing historical predictors. Climatic descriptors were represented by the first two axis of a Principal Component Analysis. Spatial predictors in different spatial scales were described by Moran Eigenvector Maps. Redundancy Analysis was implemented to partition the explained variation of species composition by geomorphological, climatic and spatial predictors. Moreover, spatial autocorrelation analyses were used to test neutral theory predictions. Beta diversity was spatially structured in broader scales. Shared fraction between climatic and geomorphological variables was an important predictor of species composition (13%, as well as broad scale spatial predictors (13%. However, geomorphological variables alone were the most important predictor of beta diversity (42%. Historical factors related to geomorphology must have played a crucial role in structuring amphibian beta diversity. The complex relationships between geomorphological history and climatic gradients generated by the Serra do Mar Precambrian basements were also important. We highlight the importance of combining spatially explicit historical and contemporary predictors for

  6. Geomorphology Drives Amphibian Beta Diversity in Atlantic Forest Lowlands of Southeastern Brazil.

    Science.gov (United States)

    Luiz, Amom Mendes; Leão-Pires, Thiago Augusto; Sawaya, Ricardo J

    2016-01-01

    Beta diversity patterns are the outcome of multiple processes operating at different scales. Amphibian assemblages seem to be affected by contemporary climate and dispersal-based processes. However, historical processes involved in present patterns of beta diversity remain poorly understood. We assess and disentangle geomorphological, climatic and spatial drivers of amphibian beta diversity in coastal lowlands of the Atlantic Forest, southeastern Brazil. We tested the hypothesis that geomorphological factors are more important in structuring anuran beta diversity than climatic and spatial factors. We obtained species composition via field survey (N = 766 individuals), museum specimens (N = 9,730) and literature records (N = 4,763). Sampling area was divided in four spatially explicit geomorphological units, representing historical predictors. Climatic descriptors were represented by the first two axis of a Principal Component Analysis. Spatial predictors in different spatial scales were described by Moran Eigenvector Maps. Redundancy Analysis was implemented to partition the explained variation of species composition by geomorphological, climatic and spatial predictors. Moreover, spatial autocorrelation analyses were used to test neutral theory predictions. Beta diversity was spatially structured in broader scales. Shared fraction between climatic and geomorphological variables was an important predictor of species composition (13%), as well as broad scale spatial predictors (13%). However, geomorphological variables alone were the most important predictor of beta diversity (42%). Historical factors related to geomorphology must have played a crucial role in structuring amphibian beta diversity. The complex relationships between geomorphological history and climatic gradients generated by the Serra do Mar Precambrian basements were also important. We highlight the importance of combining spatially explicit historical and contemporary predictors for understanding

  7. Loss of heterozygosity drives clonal diversity of Phytophthora capsici in China.

    Directory of Open Access Journals (Sweden)

    Jian Hu

    Full Text Available Phytophthora capsici causes significant loss to pepper (Capsicum annum in China and our goal was to develop single nucleotide polymorphism (SNP markers for P. capsici and characterize genetic diversity nationwide. Eighteen isolates of P. capsici from locations worldwide were re-sequenced and candidate nuclear and mitochondrial SNPs identified. From 2006 to 2012, 276 isolates of P. capsici were recovered from 136 locations in 27 provinces and genotyped using 45 nuclear and 2 mitochondrial SNPs. There were two main mitochondrial haplotypes and 95 multi-locus genotypes (MLGs identified. Genetic diversity was geographically structured with a high level of genotypic diversity in the north and on Hainan Island in the south, suggesting outcrossing contributes to diversity in these areas. The remaining areas of China are dominated by four clonal lineages that share mitochondrial haplotypes, are almost exclusively the A1 or A2 mating type and appear to exhibit extensive diversity based on loss of heterozygosity (LOH. Analysis of SNPs directly from infected peppers confirmed LOH in field populations. One clonal lineage is dominant throughout much of the country. The overall implications for long-lived genetically diverse clonal lineages amidst a widely dispersed sexual population are discussed.

  8. Effects of dexamphetamine with and without alcohol on simulated driving.

    Science.gov (United States)

    Simons, Ries; Martens, Marieke; Ramaekers, Jan; Krul, Arno; Klöpping-Ketelaars, Ineke; Skopp, Gisela

    2012-08-01

    In party circuits dexamphetamine is frequently used in combination with alcohol. It is hypothesized that co-administration of dexamphetamine to alcohol might reduce the sedative effects of alcohol, but may potentiate risk-taking behaviour. The study was aimed at assessing the effects of alcohol, dexamphetamine and the combination of both on simulated driving and cognitive performance. Eighteen subjects participated in a randomized, crossover, placebo-controlled study employing four conditions: 10 mg dexamphetamine, 0.8 g/kg alcohol, 10 mg dexamphetamine + 0.8 g/kg alcohol, and placebo. Fundamental driving skills and risk-taking behaviour were assessed in a driving simulator. Subjects also completed vigilance and divided attention tasks, and subjective ratings. Mean BAC levels during simulated driving were between 0.91‰ and 0.64‰. Subjects using alcohol showed a significantly larger mean standard deviation of lateral position and shorter accepted gap time and distance. Use of alcohol or dexamphetamine + alcohol was associated with a higher frequency of red light running and collisions than the dexamphetamine or placebo conditions. Performance of vigilance and divided attention tasks was significantly impaired in the alcohol condition and, to a lesser degree, in the dexamphetamine + alcohol condition. Single doses of 0.8 g/kg alcohol increased risk-taking behaviours and impaired tracking, attention and reaction time during a 3-h period after drinking when BACs declined from 0.9 to 0.2 mg/ml. The stimulatory effects of co-administration of dexamphetamine 10 mg were not sufficient to overcome the impairing effects of alcohol on skills related to driving.

  9. Inter-assemblage facilitation: the functional diversity of cavity-producing beetles drives the size diversity of cavity-nesting bees.

    Science.gov (United States)

    Sydenham, Markus A K; Häusler, Lise D; Moe, Stein R; Eldegard, Katrine

    2016-01-01

    Inter-specific interactions are important drivers and maintainers of biodiversity. Compared to trophic and competitive interactions, the role of non-trophic facilitation among species has received less attention. Cavity-nesting bees nest in old beetle borings in dead wood, with restricted diameters corresponding to the body size of the bee species. The aim of this study was to test the hypothesis that the functional diversity of cavity-producing wood boring beetles - in terms of cavity diameters - drives the size diversity of cavity-nesting bees. The invertebrate communities were sampled in 30 sites, located in forested landscapes along an elevational gradient. We regressed the species richness and abundance of cavity nesting bees against the species richness and abundance of wood boring beetles, non-wood boring beetles and elevation. The proportion of cavity nesting bees in bee species assemblage was regressed against the species richness and abundance of wood boring beetles. We also tested the relationships between the size diversity of cavity nesting bees and wood boring beetles. The species richness and abundance of cavity nesting bees increased with the species richness and abundance of wood boring beetles. No such relationship was found for non-wood boring beetles. The abundance of wood boring beetles was also related to an increased proportion of cavity nesting bee individuals. Moreover, the size diversity of cavity-nesting bees increased with the functional diversity of wood boring beetles. Specifically, the mean and dispersion of bee body sizes increased with the functional dispersion of large wood boring beetles. The positive relationships between cavity producing bees and cavity nesting bees suggest that non-trophic facilitative interactions between species assemblages play important roles in organizing bee species assemblages. Considering a community-wide approach may therefore be required if we are to successfully understand and conserve wild bee

  10. Mechanisms of the negative synergy effect between electron cyclotron current drive and lower hybrid current drive in tokamak

    International Nuclear Information System (INIS)

    Chen Shaoyong; Hong Binbin; Tang Changjian; Yang Wen; Zhang Xinjun

    2013-01-01

    The synergy current drive by combining electron cyclotron wave (ECW) with lower hybrid wave (LHW) can be used to either increase the noninductive current drive efficiency or shape the plasma current profile. In this paper, the synergy current drive by ECW and LHW is studied with numerical simulation. The nonlinear relationship between the wave powers and the synergy current of ECW and LHW is revealed. When the LHW power is small, the synergy current reduces as the ECW power increases, and the synergy current is even reduced to lower than zero, which is referred as negative synergy in the this context. Research shows that the mechanism of the negative synergy is the peaking effect of LHW power profile and the trapped electrons effect. The present research is helpful for understanding the physics of synergy between electron cyclotron current drive and lower hybrid current drive, it can also instruct the design of experiments. (authors)

  11. Effects of decades of physical driving on body movement and motion sickness during virtual driving.

    Directory of Open Access Journals (Sweden)

    Thomas A Stoffregen

    Full Text Available We investigated relations between experience driving physical automobiles and motion sickness during the driving of virtual automobiles. Middle-aged individuals drove a virtual automobile in a driving video game. Drivers were individuals who had possessed a driver's license for approximately 30 years, and who drove regularly, while non-drivers were individuals who had never held a driver's license, or who had not driven for more than 15 years. During virtual driving, we monitored movement of the head and torso. During virtual driving, drivers became motion sick more rapidly than non-drivers, but the incidence and severity of motion sickness did not differ as a function of driving experience. Patterns of movement during virtual driving differed as a function of driving experience. Separately, movement differed between participants who later became motion sick and those who did not. Most importantly, physical driving experience influenced patterns of postural activity that preceded motion sickness during virtual driving. The results are consistent with the postural instability theory of motion sickness, and help to illuminate relations between the control of physical and virtual vehicles.

  12. Ant and Mite Diversity Drives Toxin Variation in the Little Devil Poison Frog.

    Science.gov (United States)

    McGugan, Jenna R; Byrd, Gary D; Roland, Alexandre B; Caty, Stephanie N; Kabir, Nisha; Tapia, Elicio E; Trauger, Sunia A; Coloma, Luis A; O'Connell, Lauren A

    2016-06-01

    Poison frogs sequester chemical defenses from arthropod prey, although the details of how arthropod diversity contributes to variation in poison frog toxins remains unclear. We characterized skin alkaloid profiles in the Little Devil poison frog, Oophaga sylvatica (Dendrobatidae), across three populations in northwestern Ecuador. Using gas chromatography/mass spectrometry, we identified histrionicotoxins, 3,5- and 5,8-disubstituted indolizidines, decahydroquinolines, and lehmizidines as the primary alkaloid toxins in these O. sylvatica populations. Frog skin alkaloid composition varied along a geographical gradient following population distribution in a principal component analysis. We also characterized diversity in arthropods isolated from frog stomach contents and confirmed that O. sylvatica specialize on ants and mites. To test the hypothesis that poison frog toxin variability reflects species and chemical diversity in arthropod prey, we (1) used sequencing of cytochrome oxidase 1 to identify individual prey specimens, and (2) used liquid chromatography/mass spectrometry to chemically profile consumed ants and mites. We identified 45 ants and 9 mites in frog stomachs, including several undescribed species. We also showed that chemical profiles of consumed ants and mites cluster by frog population, suggesting different frog populations have access to chemically distinct prey. Finally, by comparing chemical profiles of frog skin and isolated prey items, we traced the arthropod source of four poison frog alkaloids, including 3,5- and 5,8-disubstituted indolizidines and a lehmizidine alkaloid. Together, the data show that toxin variability in O. sylvatica reflects chemical diversity in arthropod prey.

  13. Detection of braking intention in diverse situations during simulated driving based on EEG feature combination.

    Science.gov (United States)

    Kim, Il-Hwa; Kim, Jeong-Woo; Haufe, Stefan; Lee, Seong-Whan

    2015-02-01

    We developed a simulated driving environment for studying neural correlates of emergency braking in diversified driving situations. We further investigated to what extent these neural correlates can be used to detect a participant's braking intention prior to the behavioral response. We measured electroencephalographic (EEG) and electromyographic signals during simulated driving. Fifteen participants drove a virtual vehicle and were exposed to several kinds of traffic situations in a simulator system, while EEG signals were measured. After that, we extracted characteristic features to categorize whether the driver intended to brake or not. Our system shows excellent detection performance in a broad range of possible emergency situations. In particular, we were able to distinguish three different kinds of emergency situations (sudden stop of a preceding vehicle, sudden cutting-in of a vehicle from the side and unexpected appearance of a pedestrian) from non-emergency (soft) braking situations, as well as from situations in which no braking was required, but the sensory stimulation was similar to stimulations inducing an emergency situation (e.g., the sudden stop of a vehicle on a neighboring lane). We proposed a novel feature combination comprising movement-related potentials such as the readiness potential, event-related desynchronization features besides the event-related potentials (ERP) features used in a previous study. The performance of predicting braking intention based on our proposed feature combination was superior compared to using only ERP features. Our study suggests that emergency situations are characterized by specific neural patterns of sensory perception and processing, as well as motor preparation and execution, which can be utilized by neurotechnology based braking assistance systems.

  14. Detection of braking intention in diverse situations during simulated driving based on EEG feature combination

    Science.gov (United States)

    Kim, Il-Hwa; Kim, Jeong-Woo; Haufe, Stefan; Lee, Seong-Whan

    2015-02-01

    Objective. We developed a simulated driving environment for studying neural correlates of emergency braking in diversified driving situations. We further investigated to what extent these neural correlates can be used to detect a participant's braking intention prior to the behavioral response. Approach. We measured electroencephalographic (EEG) and electromyographic signals during simulated driving. Fifteen participants drove a virtual vehicle and were exposed to several kinds of traffic situations in a simulator system, while EEG signals were measured. After that, we extracted characteristic features to categorize whether the driver intended to brake or not. Main results. Our system shows excellent detection performance in a broad range of possible emergency situations. In particular, we were able to distinguish three different kinds of emergency situations (sudden stop of a preceding vehicle, sudden cutting-in of a vehicle from the side and unexpected appearance of a pedestrian) from non-emergency (soft) braking situations, as well as from situations in which no braking was required, but the sensory stimulation was similar to stimulations inducing an emergency situation (e.g., the sudden stop of a vehicle on a neighboring lane). Significance. We proposed a novel feature combination comprising movement-related potentials such as the readiness potential, event-related desynchronization features besides the event-related potentials (ERP) features used in a previous study. The performance of predicting braking intention based on our proposed feature combination was superior compared to using only ERP features. Our study suggests that emergency situations are characterized by specific neural patterns of sensory perception and processing, as well as motor preparation and execution, which can be utilized by neurotechnology based braking assistance systems.

  15. THE EFFECT OF CELLULAR PHONE USE ON DRIVING PERFORMANCE

    OpenAIRE

    Toshiro ISHIDA

    2001-01-01

    Many experiments using driving simulators or real roads have shown that using a cellular phone while driving may cause an accident because it delays visual information processing by the driver. In this research, we examined the influence on driving performance of cellular phone use on a course that simulated streets. Driving conditions were driving only, listening to the car radio, hands-free cellular phone use and using a cellular phone with the left hand. Driving performance measurements in...

  16. THE EFFECT OF CANNABIS COMPARED WITH ALCOHOL ON DRIVING

    OpenAIRE

    Sewell, R. Andrew; Poling, James; Sofuoglu, Mehmet

    2009-01-01

    The prevalence of both alcohol and cannabis use and the high morbidity associated with motor vehicle crashes has lead to a plethora of research on the link between the two. Drunk drivers are involved in 25% of motor vehicle fatalities, and many accidents involve drivers who test positive for cannabis. Cannabis and alcohol acutely impair several driving-related skills in a dose-related fashion, but the effects of cannabis vary more between individuals than they do with alcohol because of toler...

  17. Species turnover drives β-diversity patterns across multiple spatial scales of plant-galling interactions in mountaintop grasslands.

    Science.gov (United States)

    Coelho, Marcel Serra; Carneiro, Marco Antônio Alves; Branco, Cristina Alves; Borges, Rafael Augusto Xavier; Fernandes, Geraldo Wilson

    2018-01-01

    This study describes differences in species richness and composition of the assemblages of galling insects and their host plants at different spatial scales. Sampling was conducted along altitudinal gradients composed of campos rupestres and campos de altitude of two mountain complexes in southeastern Brazil: Espinhaço Range and Mantiqueira Range. The following hypotheses were tested: i) local and regional richness of host plants and galling insects are positively correlated; ii) beta diversity is the most important component of regional diversity of host plants and galling insects; and iii) Turnover is the main mechanism driving beta diversity of both host plants and galling insects. Local richness of galling insects and host plants increased with increasing regional richness of species, suggesting a pattern of unsaturated communities. The additive partition of regional richness (γ) into local and beta components shows that local richnesses (α) of species of galling insects and host plants are low relative to regional richness; the beta (β) component incorporates most of the regional richness. The multi-scale analysis of additive partitioning showed similar patterns for galling insects and host plants with the local component (α) incorporated a small part of regional richness. Beta diversity of galling insects and host plants were mainly the result of turnover, with little contribution from nesting. Although the species composition of galling insects and host plant species varied among sample sites, mountains and even mountain ranges, local richness remained relatively low. In this way, the addition of local habitats with different landscapes substantially affects regional richness. Each mountain contributes fundamentally to the composition of regional diversity of galling insects and host plants, and so the design of future conservation strategies should incorporate multiple scales.

  18. Region effects influence local tree species diversity.

    Science.gov (United States)

    Ricklefs, Robert E; He, Fangliang

    2016-01-19

    Global patterns of biodiversity reflect both regional and local processes, but the relative importance of local ecological limits to species coexistence, as influenced by the physical environment, in contrast to regional processes including species production, dispersal, and extinction, is poorly understood. Failure to distinguish regional influences from local effects has been due, in part, to sampling limitations at small scales, environmental heterogeneity within local or regional samples, and incomplete geographic sampling of species. Here, we use a global dataset comprising 47 forest plots to demonstrate significant region effects on diversity, beyond the influence of local climate, which together explain more than 92% of the global variation in local forest tree species richness. Significant region effects imply that large-scale processes shaping the regional diversity of forest trees exert influence down to the local scale, where they interact with local processes to determine the number of coexisting species.

  19. Factors driving changes in freshwater mussel (Bivalvia, Unionida) diversity and distribution in Peninsular Malaysia.

    Science.gov (United States)

    Zieritz, Alexandra; Lopes-Lima, Manuel; Bogan, Arthur E; Sousa, Ronaldo; Walton, Samuel; Rahim, Khairul Adha A; Wilson, John-James; Ng, Pei-Yin; Froufe, Elsa; McGowan, Suzanne

    2016-11-15

    Freshwater mussels (Bivalvia, Unionida) fulfil important ecosystem functions and are one of the most threatened freshwater taxa globally. Knowledge of freshwater mussel diversity, distribution and ecology in Peninsular Malaysia is extremely poor, and the conservation status of half of the species presumed to occur in the region has yet to be assessed. We conducted the first comprehensive assessment of Peninsular Malaysia's freshwater mussels based on species presence/absence and environmental data collected from 155 sites spanning all major river catchments and diverse habitat types. Through an integrative morphological-molecular approach we recognised nine native and one widespread non-native species, i.e. Sinanodonta woodiana. Two species, i.e. Pilsbryoconcha compressa and Pseudodon cambodjensis, had not been previously recorded from Malaysia, which is likely a result of morphological misidentifications of historical records. Due to their restriction to single river catchments and declining distributions, Hyriopsis bialata, possibly endemic to Peninsular Malaysia, Ensidens ingallsianus, possibly already extinct in the peninsula, and Rectidens sumatrensis, particularly require conservation attention. Equally, the Pahang, the Perak and the north-western river catchments are of particular conservation value due to the presence of a globally unique freshwater mussel fauna. Statistical relationships of 15 water quality parameters and mussel presence/absence identified acidification and nutrient pollution (eutrophication) as the most important anthropogenic factors threatening freshwater mussel diversity in Peninsular Malaysia. These factors can be linked to atmospheric pollution, deforestation, oil-palm plantations and a lack of functioning waste water treatment, and could be mitigated by establishing riparian buffers and improving waste water treatment for rivers running through agricultural and residential land. Copyright © 2016 Elsevier B.V. All rights reserved.

  20. Macro and Microelements Drive Diversity and Composition of Prokaryotic and Fungal Communities in Hypersaline Sediments and Saline-Alkaline Soils.

    Science.gov (United States)

    Liu, Kaihui; Ding, Xiaowei; Tang, Xiaofei; Wang, Jianjun; Li, Wenjun; Yan, Qingyun; Liu, Zhenghua

    2018-01-01

    Understanding the effects of environmental factors on microbial communities is critical for microbial ecology, but it remains challenging. In this study, we examined the diversity (alpha diversity) and community compositions (beta diversity) of prokaryotes and fungi in hypersaline sediments and salinized soils from northern China. Environmental variables were highly correlated, but they differed significantly between the sediments and saline soils. The compositions of prokaryotic and fungal communities in the hypersaline sediments were different from those in adjacent saline-alkaline soils, indicating a habitat-specific microbial distribution pattern. The macroelements (S, P, K, Mg, and Fe) and Ca were, respectively, correlated closely with the alpha diversity of prokaryotes and fungi, while the macronutrients (e.g., Na, S, P, and Ca) were correlated with the prokaryotic and fungal beta-diversity ( P ≤ 0.05). And, the nine microelements (e.g., Al, Ba, Co, Hg, and Mn) and micronutrients (Ba, Cd, and Sr) individually shaped the alpha diversity of prokaryotes and fungi, while the six microelements (e.g., As, Ba, Cr, and Ge) and only the trace elements (Cr and Cu), respectively, influenced the beta diversity of prokaryotes and fungi ( P analysis (VPA) showed that environmental variables jointly explained 55.49% and 32.27% of the total variation for the prokaryotic and fungal communities, respectively. Together, our findings demonstrate that the diversity and community composition of the prokaryotes and fungi were driven by different macro and microelements in saline habitats, and that geochemical elements could more widely regulate the diversity and community composition of prokaryotes than these of fungi.

  1. Macro and Microelements Drive Diversity and Composition of Prokaryotic and Fungal Communities in Hypersaline Sediments and Saline–Alkaline Soils

    Science.gov (United States)

    Liu, Kaihui; Ding, Xiaowei; Tang, Xiaofei; Wang, Jianjun; Li, Wenjun; Yan, Qingyun; Liu, Zhenghua

    2018-01-01

    Understanding the effects of environmental factors on microbial communities is critical for microbial ecology, but it remains challenging. In this study, we examined the diversity (alpha diversity) and community compositions (beta diversity) of prokaryotes and fungi in hypersaline sediments and salinized soils from northern China. Environmental variables were highly correlated, but they differed significantly between the sediments and saline soils. The compositions of prokaryotic and fungal communities in the hypersaline sediments were different from those in adjacent saline–alkaline soils, indicating a habitat-specific microbial distribution pattern. The macroelements (S, P, K, Mg, and Fe) and Ca were, respectively, correlated closely with the alpha diversity of prokaryotes and fungi, while the macronutrients (e.g., Na, S, P, and Ca) were correlated with the prokaryotic and fungal beta-diversity (P ≤ 0.05). And, the nine microelements (e.g., Al, Ba, Co, Hg, and Mn) and micronutrients (Ba, Cd, and Sr) individually shaped the alpha diversity of prokaryotes and fungi, while the six microelements (e.g., As, Ba, Cr, and Ge) and only the trace elements (Cr and Cu), respectively, influenced the beta diversity of prokaryotes and fungi (P analysis (VPA) showed that environmental variables jointly explained 55.49% and 32.27% of the total variation for the prokaryotic and fungal communities, respectively. Together, our findings demonstrate that the diversity and community composition of the prokaryotes and fungi were driven by different macro and microelements in saline habitats, and that geochemical elements could more widely regulate the diversity and community composition of prokaryotes than these of fungi. PMID:29535703

  2. Electron Bernstein wave heating and current drive effects in QUEST

    International Nuclear Information System (INIS)

    Idei, H.; Zushi, H.; Hanada, K.; Nakamura, K.; Fujisawa, A.; Nagashima, Y.; Hasegawa, M.; Matsuoka, K.; Watanabe, H.; Yoshida, N.; Tokunaga, K.; Kawasaki, S.; Nakashima, H.; Higashijima, A.; Kalinnikova, E.; Sakaguchi, M.; Itado, T.; Tashima, S.; Fukuyama, A.; Ejiri, A.; Takase, Y.; Igami, H.; Kubo, S.; Toi, K.; Isobe, M.; Nagaoka, K.; Nakanishi, H.; Nishino, N.; Ueda, Y.; Kikuchi, Mitsuru; Fujita, Takaaki; Mitarai, O.; Maekawa, T.

    2012-11-01

    Electron Bernstein Wave Heating and Current Drive (EBWH/CD) effects have been first observed in over dense plasmas using the developed phased-array antenna (PAA) system in QUEST. Good focusing and steering properties tested in the low power facilities were confirmed with a high power level in the QUEST device. The new operational window to sustain the plasma current was observed in the RF-sustained high-density plasmas at the higher incident RF power. Increment and decrement of the plasma current and the loop voltage were observed in the over dense ohmic plasma by the RF injection respectively, indicating the EBWH/CD effects. (author)

  3. Effects of above-ground plant species composition and diversity on the diversity of soil-borne microorganisms

    NARCIS (Netherlands)

    Kowalchuk, G.A.; Buma, D.S; De Boer, W.; Klinkhamer, P.G.L.; Van Veen, J.A.

    2002-01-01

    A coupling of above-ground plant diversity and below-ground microbial diversity has been implied in studies dedicated to assessing the role of macrophyte diversity on the stability, resilience, and functioning of ecosystems. Indeed, above-ground plant communities have long been assumed to drive

  4. Resource partitioning along multiple niche axes drives functional diversity in parrotfishes on Caribbean coral reefs.

    Science.gov (United States)

    Adam, Thomas C; Kelley, Megan; Ruttenberg, Benjamin I; Burkepile, Deron E

    2015-12-01

    The recent loss of key consumers to exploitation and habitat degradation has significantly altered community dynamics and ecosystem function across many ecosystems worldwide. Predicting the impacts of consumer losses requires knowing the level of functional diversity that exists within a consumer assemblage. In this study, we document functional diversity among nine species of parrotfishes on Caribbean coral reefs. Parrotfishes are key herbivores that facilitate the maintenance and recovery of coral-dominated reefs by controlling algae and provisioning space for the recruitment of corals. We observed large functional differences among two genera of parrotfishes that were driven by differences in diet. Fishes in the genus Scarus targeted filamentous algal turf assemblages, crustose coralline algae, and endolithic algae and avoided macroalgae, while fishes in the genus Sparisoma preferentially targeted macroalgae. However, species with similar diets were dissimilar in other attributes, including the habitats they frequented, the types of substrate they fed from, and the spatial scale at which they foraged. These differences indicate that species that appear to be functionally redundant when looking at diet alone exhibit high levels of complementarity when we consider multiple functional traits. By identifying key functional differences among parrotfishes, we provide critical information needed to manage parrotfishes to enhance the resilience of coral-dominated reefs and reverse phase shifts on algal-dominated reefs throughout the wider Caribbean. Further, our study provides a framework for predicting the impacts of consumer losses in other species rich ecosystems.

  5. Effects of MDMA (ecstasy), and multiple drugs use on (simulated) driving performance and traffic safety

    NARCIS (Netherlands)

    Brookhuis, KA; de Waard, D; Samyn, N

    Rationale. The effects of MDMA on driving behaviour are not clear, since the direct effects of MDMA on cognitive performance are reported as not generally negative. Objectives. To assess in an advanced driving simulator acute effects on simulated driving behaviour and heart rate of MDMA, and effects

  6. Energy conversion efficiency of hybrid electric heavy-duty vehicles operating according to diverse drive cycles

    Energy Technology Data Exchange (ETDEWEB)

    Banjac, Titina [AVL-AST d.o.o., Trg Leona Stuklja 5, SI-2000 Maribor (Slovenia); Trenc, Ferdinand; Katrasnik, Tomaz [Faculty of Mechanical Engineering, Univ. of Ljubljana, Askerceva 6, SI-1000 Ljubljana (Slovenia)

    2009-12-15

    Energy consumption and exhaust emissions of hybrid electric vehicles (HEVs) strongly depend on the HEV topology, power ratios of their components and applied control strategy. Combined analytical and simulation approach was applied to analyze energy conversion efficiency of different HEV topologies. Analytical approach is based on the energy balance equations and considers all energy paths in the HEVs from the energy sources to the wheels and to other energy sinks. Simulation approach is based on a fast forward-facing simulation model for simulating parallel and series HEVs as well as for conventional internal combustion engine vehicles, and considers all components relevant for modeling energy conversion phenomena. Combined approach enables evaluation of energy losses on different energy paths and provides their impact on the fuel economy. It therefore enables identification of most suitable HEV topology and of most suitable power ratios of the components for targeted vehicle application, since it reveals and quantifies the mechanisms that could lead to improved energy conversion efficiency of particular HEV. The paper exposes characteristics of the test cycles that lead to improved energy conversion efficiency of HEVs. Mechanisms leading to improved fuel economy of parallel HEVs through drive-away and vehicle propulsion at low powertrain loads by electric motor are also analyzed. It was also shown that control strategies managing energy flow through electric storage devices significantly influence energy conversion efficiency of series HEVs. (author)

  7. The effect of stress and personality on dangerous driving behavior among Chinese drivers.

    Science.gov (United States)

    Ge, Yan; Qu, Weina; Jiang, Caihong; Du, Feng; Sun, Xianghong; Zhang, Kan

    2014-12-01

    The relationship between stress and road safety has been studied for many years, but the effect of global stress and its joint effect with personality on driving behavior have received little attention in previous studies. This study aimed to elucidate the impact of global stress and various personality traits on driving behavior. 242 drivers completed the Perceived Stress Scale-10 (PSS-10), the Dula Dangerous Driving Index (DDDI), and several personality trait scales related to anger, sensation seeking, and altruism. The results showed that perceived stress and sensation seeking were significantly correlated with the four subcategories of dangerous driving behavior, namely, negative cognitive/emotional driving (NCED), aggressive driving (AD), risky driving (RD), and drunk driving (DD). Moreover, anger was positively correlated with negative cognitive/emotional driving, aggressive driving, and risky driving, and altruism was negatively correlated with aggressive driving and drunk driving. Hierarchical multiple regressions were applied to analyze the mediating effect of personality traits, and the results showed that anger mediated the relationship between stress and dangerous driving behavior and that this mediating role was especially strong for negative cognitive/emotional driving and aggressive driving. Collectively, the results showed that stress is an important factor that can affect people's driving behavior but that personality traits mediate the effect of stress on driving behavior. The findings from this study regarding the relationship among stress, anger, and dangerous driving behavior could be applied in the development of intervention programs for stress and anger management in order to improve drivers' ability to manage emotional thoughts and adjust their behavior on the road. Copyright © 2014 Elsevier Ltd. All rights reserved.

  8. Effect of tailored on-road driving lessons on driving safety in older adults: A randomised controlled trial.

    Science.gov (United States)

    Anstey, Kaarin J; Eramudugolla, Ranmalee; Kiely, Kim M; Price, Jasmine

    2018-06-01

    We evaluated the effectiveness of individually tailored driving lessons compared with a road rules refresher course for improving older driver safety. Two arm parallel randomised controlled trial, involving current drivers aged 65 and older (Mean age 72.0, 47.4% male) residing in Canberra, Australia. The intervention group (n = 28) received a two-hour class-based road rules refresher course, and two one-hour driving lessons tailored to improve poor driving skills and habits identified in a baseline on-road assessment. The control group (n = 29) received the road rules refresher course only. Tests of cognitive performance, and on-road driving were conducted at baseline and at 12-weeks. Main outcome measure was the Driver safety rating (DSR) on the on-road driving test. The number of Critical Errors made during the on-road was also recorded. 55 drivers completed the trial (intervention group: 27, control group: 28). Both groups showed reduction in dangerous/hazardous driver errors that required instructor intervention. From baseline to follow-up there was a greater reduction in the number of critical errors made by the intervention group relative to the control group (IRR = 0.53, SE = 0.1, p = .008). The intervention group improved on the DSR more than the control group (intervention mean change = 1.07 SD = 2.00, control group mean change = 0.32 SD = 1.61). The intervention group had 64% remediation of unsafe driving, where drivers who achieved a score of 'fail' at baseline, 'passed' at follow-up. The control group had 25% remediation. Tailored driving lessons reduced the critical driving errors made by older adults. Longer term follow-up and larger trials are required. Copyright © 2018 Elsevier Ltd. All rights reserved.

  9. Effect of discrete RF spectrum on fast wave current drive

    International Nuclear Information System (INIS)

    Okazaki, Takashi; Yoshioka, Ken; Sugihara, Masayoshi

    1987-08-01

    Effect of discrete RF spectrum has been studied for the fast wave current drive with the ion cyclotron range of frequency. Driven current and power densities decrease in this spectrum than in the continuous spectrum. However, there is a possibility to have the mechanism which allows electrons outside the resonance region to interact with the fast wave, taking into account the electron trapping by discrete RF spectrum. In the case of neglecting the electron trapping effect, driven current and power densities decrease up to 0.6 - 0.8 of those which are obtained for the continuous spectrum for the FER (Fusion Experimental Reactor). However, their driven current and power densities can be almost doubled in their magnitude for the discrete spectrum by taking into account the trapping effect. (author)

  10. [Effect of highway driving on the health of factory workers].

    Science.gov (United States)

    Uramoto, Hidetaka

    2008-06-01

    Commuting transportation is one of the important factors in the administration of safety management in industries. Most workers commute to work by car and are certain to make use of highways, mainly because of the special condition of factory locations. In this study, we investigated the effect of communicating by car on the health of factory workers. The proportion of males was significantly higher in the highway (HW) group than in the non-highway (NHW) group, and the former was younger than the latter. BMI, systolic blood pressure, diastolic blood pressure, and total cholesterol deteriorated significantly in the NHW group after 5-year periodic medical checkups. However, in the HW group, those factors did not change except for systolic blood pressure and significant improvements in triglyceride. The percentage of those who follow a good lifestyle regarding excise and nutrition, and have a solution for stress, was lower in the HW group than in the NHW group. Nevertheless, the percentage of those who did not feel stress was significantly higher in the HW group than in the NHW group, suggesting a stress-relieving effect of highway driving. Highway driving might have an unexpectedly good impact on the health of factory workers.

  11. Tree species identity and diversity drive fungal richness and community composition along an elevational gradient in a Mediterranean ecosystem.

    Science.gov (United States)

    Saitta, Alessandro; Anslan, Sten; Bahram, Mohammad; Brocca, Luca; Tedersoo, Leho

    2018-01-01

    Ecological and taxonomic knowledge is important for conservation and utilization of biodiversity. Biodiversity and ecology of fungi in Mediterranean ecosystems is poorly understood. Here, we examined the diversity and spatial distribution of fungi along an elevational gradient in a Mediterranean ecosystem, using DNA metabarcoding. This study provides novel information about diversity of all ecological and taxonomic groups of fungi along an elevational gradient in a Mediterranean ecosystem. Our analyses revealed that among all biotic and abiotic variables tested, host species identity is the main driver of the fungal richness and fungal community composition. Fungal richness was strongly associated with tree richness and peaked in Quercus-dominated habitats and Cistus-dominated habitats. The highest taxonomic richness of ectomycorrhizal fungi was observed under Quercus ilex, whereas the highest taxonomic richness of saprotrophs was found under Pinus. Our results suggest that the effect of plant diversity on fungal richness and community composition may override that of abiotic variables across environmental gradients.

  12. A pilot study of the effects of atomoxetine on driving performance in adults with ADHD.

    Science.gov (United States)

    Barkley, Russell A; Anderson, Deborah L; Kruesi, Markus

    2007-02-01

    There is a high risk of vehicular crashes, traffic citations, and poorer driving performance in adults with ADHD. This pilot study examines the value of a new nonstimulant (atomoxetine) for improving the driving performance of adults with ADHD. Atomoxetine (1.2 mg/kg daily for 3 weeks) and a placebo are studied on 18 adults with ADHD (M age = 37 years) using ratings of ADHD symptoms, impairment, and safe driving behavior; a virtual reality driving simulator; and ratings of simulator performance. Atomoxetine improves self-ratings of ADHD symptoms, impairments, safe driving behavior, and simulator driving performance. No effects of atomoxetine are evident on others' ratings of driving behavior or on the simulator. Practice effects on the simulator may have obscured those drug effects. The authors find a mixed pattern of results such that atomoxetine warrants further study for its effects on driving in this high-risk population.

  13. The effect of virtual reality-enhanced driving protocol in patients following spinal cord injury

    Directory of Open Access Journals (Sweden)

    Wen-Hsu Sung

    2012-11-01

    Conclusion: This study shows the significant effect of a virtual environment on the progress of driving rehabilitation, and suggests that incorporating virtual reality into rehabilitation programs will accelerate the maximal recovery of the patient’s driving competence.

  14. Spectral Effects on Fast Wave Core Heating and Current Drive

    International Nuclear Information System (INIS)

    Phillips, C.K.; Bell, R.E.; Berry, L.A.; Bonoli, P.T.; Harvey, R.W.; Hosea, J.C.; Jaeger, E.F.; LeBlanc, B.P.; Ryan, P.M.; Taylor, G.; Valeo, E.J.; Wilson, J.R.; Wright, J.C.; Yuh, H. and the NSTX Team

    2009-01-01

    Recent results obtained with high harmonic fast wave (HHFW) heating and current drive (CD) on NSTX strongly support the hypothesis that the onset of perpendicular fast wave propagation right at or very near the launcher is a primary cause for a reduction in core heating efficiency at long wavelengths that is also observed in ICRF heating experiments in numerous tokamaks. A dramatic increase in core heating efficiency was first achieved in NSTX L-mode helium majority plasmas when the onset for perpendicular wave propagation was moved away from the antenna and nearby vessel structures. Efficient core heating in deuterium majority L mode and H mode discharges, in which the edge density is typically higher than in comparable helium majority plasmas, was then accomplished by reducing the edge density in front of the launcher with lithium conditioning and avoiding operational points prone to instabilities. These results indicate that careful tailoring of the edge density profiles in ITER should be considered to limit rf power losses to the antenna and plasma facing materials. Finally, in plasmas with reduced rf power losses in the edge regions, the first direct measurements of high harmonic fast wave current drive were obtained with the motional Stark effect (MSE) diagnostic. The location and radial dependence of HHFW CD measured by MSE are in reasonable agreement with predictions from both full wave and ray tracing simulations

  15. The Effects of Dextromethorphan on Driving Performance and the Standardized Field Sobriety Test.

    Science.gov (United States)

    Perry, Paul J; Fredriksen, Kristian; Chew, Stephanie; Ip, Eric J; Lopes, Ingrid; Doroudgar, Shadi; Thomas, Kelan

    2015-09-01

    Dextromethorphan (DXM) is abused most commonly among adolescents as a recreational drug to generate a dissociative experience. The objective of the study was to assess driving with and without DXM ingestion. The effects of one-time maximum daily doses of DXM 120 mg versus a guaifenesin 400 mg dose were compared among 40 healthy subjects using a crossover design. Subjects' ability to drive was assessed by their performance in a driving simulator (STISIM® Drive driving simulator software) and by conducting a standardized field sobriety test (SFST) administered 1-h postdrug administration. The one-time dose of DXM 120 mg did not demonstrate driving impairment on the STISIM® Drive driving simulator or increase SFST failures compared to guaifenesin 400 mg. Doses greater than the currently recommended maximum daily dose of 120 mg are necessary to perturb driving behavior. © 2015 American Academy of Forensic Sciences.

  16. Enhancing Diversity in Undergraduate Science: Self-Efficacy Drives Performance Gains with Active Learning

    OpenAIRE

    Ballen, Cissy J.; Wieman, Carl; Salehi, Shima; Searle, Jeremy B.; Zamudio, Kelly R.

    2017-01-01

    Efforts to retain underrepresented minority (URM) students in science, technology, engineering, and mathematics (STEM) have shown only limited success in higher education, due in part to a persistent achievement gap between students from historically underrepresented and well-represented backgrounds. To test the hypothesis that active learning disproportionately benefits URM students, we quantified the effects of traditional versus active learning on student academic performance, science self...

  17. Driving simulator sickness: Impact on driving performance, influence of blood alcohol concentration, and effect of repeated simulator exposures.

    Science.gov (United States)

    Helland, Arne; Lydersen, Stian; Lervåg, Lone-Eirin; Jenssen, Gunnar D; Mørland, Jørg; Slørdal, Lars

    2016-09-01

    Simulator sickness is a major obstacle to the use of driving simulators for research, training and driver assessment purposes. The purpose of the present study was to investigate the possible influence of simulator sickness on driving performance measures such as standard deviation of lateral position (SDLP), and the effect of alcohol or repeated simulator exposure on the degree of simulator sickness. Twenty healthy male volunteers underwent three simulated driving trials of 1h's duration with a curvy rural road scenario, and rated their degree of simulator sickness after each trial. Subjects drove sober and with blood alcohol concentrations (BAC) of approx. 0.5g/L and 0.9g/L in a randomized order. Simulator sickness score (SSS) did not influence the primary outcome measure SDLP. Higher SSS significantly predicted lower average speed and frequency of steering wheel reversals. These effects seemed to be mitigated by alcohol. Higher BAC significantly predicted lower SSS, suggesting that alcohol inebriation alleviates simulator sickness. The negative relation between the number of previous exposures to the simulator and SSS was not statistically significant, but is consistent with habituation to the sickness-inducing effects, as shown in other studies. Overall, the results suggest no influence of simulator sickness on SDLP or several other driving performance measures. However, simulator sickness seems to cause test subjects to drive more carefully, with lower average speed and fewer steering wheel reversals, hampering the interpretation of these outcomes as measures of driving impairment and safety. BAC and repeated simulator exposures may act as confounding variables by influencing the degree of simulator sickness in experimental studies. Copyright © 2016 Elsevier Ltd. All rights reserved.

  18. Enhancing Diversity in Undergraduate Science: Self-Efficacy Drives Performance Gains with Active Learning.

    Science.gov (United States)

    Ballen, Cissy J; Wieman, Carl; Salehi, Shima; Searle, Jeremy B; Zamudio, Kelly R

    2017-01-01

    Efforts to retain underrepresented minority (URM) students in science, technology, engineering, and mathematics (STEM) have shown only limited success in higher education, due in part to a persistent achievement gap between students from historically underrepresented and well-represented backgrounds. To test the hypothesis that active learning disproportionately benefits URM students, we quantified the effects of traditional versus active learning on student academic performance, science self-efficacy, and sense of social belonging in a large (more than 250 students) introductory STEM course. A transition to active learning closed the gap in learning gains between non-URM and URM students and led to an increase in science self-efficacy for all students. Sense of social belonging also increased significantly with active learning, but only for non-URM students. Through structural equation modeling, we demonstrate that, for URM students, the increase in self-efficacy mediated the positive effect of active-learning pedagogy on two metrics of student performance. Our results add to a growing body of research that supports varied and inclusive teaching as one pathway to a diversified STEM workforce. © 2017 C. J. Ballen et al. CBE—Life Sciences Education © 2017 The American Society for Cell Biology. This article is distributed by The American Society for Cell Biology under license from the author(s). It is available to the public under an Attribution–Noncommercial–Share Alike 3.0 Unported Creative Commons License (http://creativecommons.org/licenses/by-nc-sa/3.0).

  19. Plant litter functional diversity effects on litter mass loss depend on the macro-detritivore community.

    Science.gov (United States)

    Patoine, Guillaume; Thakur, Madhav P; Friese, Julia; Nock, Charles; Hönig, Lydia; Haase, Josephine; Scherer-Lorenzen, Michael; Eisenhauer, Nico

    2017-11-01

    A better understanding of the mechanisms driving litter diversity effects on decomposition is needed to predict how biodiversity losses affect this crucial ecosystem process. In a microcosm study, we investigated the effects of litter functional diversity and two major groups of soil macro-detritivores on the mass loss of tree leaf litter mixtures. Furthermore, we tested the effects of litter trait community means and dissimilarity on litter mass loss for seven traits relevant to decomposition. We expected macro-detritivore effects on litter mass loss to be most pronounced in litter mixtures of high functional diversity. We used 24 leaf mixtures differing in functional diversity, which were composed of litter from four species from a pool of 16 common European tree species. Earthworms, isopods, or a combination of both were added to each litter combination for two months. Litter mass loss was significantly higher in the presence of earthworms than in that of isopods, whereas no synergistic effects of macro-detritivore mixtures were found. The effect of functional diversity of the litter material was highest in the presence of both macro-detritivore groups, supporting the notion that litter diversity effects are most pronounced in the presence of different detritivore species. Species-specific litter mass loss was explained by nutrient content, secondary compound concentration, and structural components. Moreover, dissimilarity in N concentrations increased litter mass loss, probably because detritivores having access to nutritionally diverse food sources. Furthermore, strong competition between the two macro-detritivores for soil surface litter resulted in a decrease of survival of both macro-detritivores. These results show that the effects of litter functional diversity on decomposition are contingent upon the macro-detritivore community and composition. We conclude that the temporal dynamics of litter trait diversity effects and their interaction with

  20. The effects of a driving mechanism on Oslo models

    International Nuclear Information System (INIS)

    Pan, Gui-Jun; Pan, Yong-Cai

    2010-01-01

    Isotropic and anisotropic Oslo models (IOM and AOM) under a bulk driving mechanism have been investigated. We apply the moment analysis to evaluate critical exponents and the finite size scaling method to consistently test the obtained results. We find that both types of Oslo model have different critical behaviour. However, the critical exponents are the same for deterministic and random IOMs, and are independent of the strength of the anisotropy for the AOM. In contrast to a boundary driving mechanism, we find that the critical exponents depend crucially on the driving mechanism for the IOM, and are independent of the driving mechanism for the AOM.

  1. Resource-Mediated Indirect Effects of Grassland Management on Arthropod Diversity

    Science.gov (United States)

    Simons, Nadja K.; Gossner, Martin M.; Lewinsohn, Thomas M.; Boch, Steffen; Lange, Markus; Müller, Jörg; Pašalić, Esther; Socher, Stephanie A.; Türke, Manfred; Fischer, Markus; Weisser, Wolfgang W.

    2014-01-01

    Intensive land use is a driving force for biodiversity decline in many ecosystems. In semi-natural grasslands, land-use activities such as mowing, grazing and fertilization affect the diversity of plants and arthropods, but the combined effects of different drivers and the chain of effects are largely unknown. In this study we used structural equation modelling to analyse how the arthropod communities in managed grasslands respond to land use and whether these responses are mediated through changes in resource diversity or resource quantity (biomass). Plants were considered resources for herbivores which themselves were considered resources for predators. Plant and arthropod (herbivores and predators) communities were sampled on 141 meadows, pastures and mown pastures within three regions in Germany in 2008 and 2009. Increasing land-use intensity generally increased plant biomass and decreased plant diversity, mainly through increasing fertilization. Herbivore diversity decreased together with plant diversity but showed no response to changes in plant biomass. Hence, land-use effects on herbivore diversity were mediated through resource diversity rather than quantity. Land-use effects on predator diversity were mediated by both herbivore diversity (resource diversity) and herbivore quantity (herbivore biomass), but indirect effects through resource quantity were stronger. Our findings highlight the importance of assessing both direct and indirect effects of land-use intensity and mode on different trophic levels. In addition to the overall effects, there were subtle differences between the different regions, pointing to the importance of regional land-use specificities. Our study underlines the commonly observed strong effect of grassland land use on biodiversity. It also highlights that mechanistic approaches help us to understand how different land-use modes affect biodiversity. PMID:25188423

  2. Diversity

    Science.gov (United States)

    Portraits In Courage Vol. VIII Portraits In Courage Vol. IX Portraits In Courage Vol. X AF Sites Social -Wide Initiative to Promote Diversity and Inclusion in the Federal Workforce Executive Order 13548 : Virtual Diversity Conference Air Force Diversity & Inclusion Air Force Diversity Graphic There is no

  3. Comparing treatment effects of oral THC on simulated and on-the-road driving performance: testing the validity of driving simulator drug research.

    Science.gov (United States)

    Veldstra, J L; Bosker, W M; de Waard, D; Ramaekers, J G; Brookhuis, K A

    2015-08-01

    The driving simulator provides a safe and controlled environment for testing driving behaviour efficiently. The question is whether it is sensitive to detect drug-induced effects. The primary aim of the current study was to investigate the sensitivity of the driving simulator for detecting drug effects. As a case in point, we investigated the dose-related effects of oral ∆(9)-tetrahydrocannabinol (THC), i.e. dronabinol, on simulator and on-the-road driving performance in equally demanding driving tasks. Twenty-four experienced driver participants were treated with dronabinol (Marinol®; 10 and 20 mg) and placebo. Dose-related effects of the drug on the ability to keep a vehicle in lane (weaving) and to follow the speed changes of a lead car (car following) were compared within subjects for on-the-road versus in-simulator driving. Additionally, the outcomes of equivalence testing to alcohol-induced effects were investigated. Treatment effects found on weaving when driving in the simulator were comparable to treatment effects found when driving on the road. The effect after 10 mg dronabinol was however less strong in the simulator than on the road and inter-individual variance seemed higher in the simulator. There was, however, a differential treatment effect of dronabinol on reactions to speed changes of a lead car (car following) when driving on the road versus when driving in the simulator. The driving simulator was proven to be sensitive for demonstrating dronabinol-induced effects particularly at higher doses. Treatment effects of dronabinol on weaving were comparable with driving on the road but inter-individual variability seemed higher in the simulator than on the road which may have potential effects on the clinical inferences made from simulator driving. Car following on the road and in the simulator were, however, not comparable.

  4. Post and during event effect of cell phone talking and texting on driving performance--a driving simulator study.

    Science.gov (United States)

    Thapa, Raju; Codjoe, Julius; Ishak, Sherif; McCarter, Kevin S

    2015-01-01

    A number of studies have been done in the field of driver distraction, specifically on the use of cell phone for either conversation or texting while driving. Researchers have focused on the driving performance of drivers when they were actually engaged in the task; that is, during the texting or phone conversation event. However, it is still unknown whether the impact of cell phone usages ceases immediately after the end of task. The primary objective of this article is to analyze the post-event effect of cell phone usage (texting and conversation) in order to verify whether the distracting effect lingers after the actual event has ceased. This study utilizes a driving simulator study of 36 participants to test whether a significant decrease in driver performance occurs during cell phone usage and after usage. Surrogate measures used to represent lateral and longitudinal control of the vehicle were standard deviation (SD) of lane position and mean velocity, respectively. RESULTS suggest that there was no significant decrease in driver performance (both lateral and longitudinal control) during and after the cell phone conversation. For the texting event, there were significant decreases in driver performance in both the longitudinal and lateral control of the vehicle during the actual texting task. The diminished longitudinal control ceased immediately after the texting event but the diminished lateral control lingered for an average of 3.38 s. The number of text messages exchanged did not affect the magnitude or duration of the diminished lateral control. The result indicates that the distraction and subsequent elevated crash risk of texting while driving linger even after the texting event has ceased. This finding has safety and policy implications in reducing distracted driving.

  5. Study of the Effects of Alcohol on Drivers and Driving Performance on Straight Road

    Directory of Open Access Journals (Sweden)

    Xiaohua Zhao

    2014-01-01

    Full Text Available Drinking driving is responsible for a high proportion of traffic accidents. To study the effects of alcohol on drivers and driving performance, 25 drivers’ subjective feelings and driving performance data in different blood-alcohol concentration (BAC levels were collected with simulated driving experiment. The investigation results revealed that alcohol affected drivers in many aspects, including attitude, judgment, vigilance, perception, reaction, and controlling. The analysis of accident rate showed that higher BAC level would lead to higher accident rate. The statistical analysis results of driving performance indicated that average speed, speed standard deviation, and lane position standard deviation were significantly higher under the influence of alcohol. They also had a statistically significant linear trend as the function of BAC level. The discrimination of drinking driving based on driving performance was performed with Fisher discrimination method. The results showed that drinking driving with higher BAC level was easier to discriminate from normal driving. Also, the results indicated that the three significant indicators on straight roadway could be used in the discrimination of drinking driving state. The conclusions can provide references for the study of drinking driving and the identification of driving state and then contribute to traffic safety.

  6. Effective World Modeling: Multisensor Data Fusion Methodology for Automated Driving.

    Science.gov (United States)

    Elfring, Jos; Appeldoorn, Rein; van den Dries, Sjoerd; Kwakkernaat, Maurice

    2016-10-11

    The number of perception sensors on automated vehicles increases due to the increasing number of advanced driver assistance system functions and their increasing complexity. Furthermore, fail-safe systems require redundancy, thereby increasing the number of sensors even further. A one-size-fits-all multisensor data fusion architecture is not realistic due to the enormous diversity in vehicles, sensors and applications. As an alternative, this work presents a methodology that can be used to effectively come up with an implementation to build a consistent model of a vehicle's surroundings. The methodology is accompanied by a software architecture. This combination minimizes the effort required to update the multisensor data fusion system whenever sensors or applications are added or replaced. A series of real-world experiments involving different sensors and algorithms demonstrates the methodology and the software architecture.

  7. Effective World Modeling: Multisensor Data Fusion Methodology for Automated Driving

    Directory of Open Access Journals (Sweden)

    Jos Elfring

    2016-10-01

    Full Text Available The number of perception sensors on automated vehicles increases due to the increasing number of advanced driver assistance system functions and their increasing complexity. Furthermore, fail-safe systems require redundancy, thereby increasing the number of sensors even further. A one-size-fits-all multisensor data fusion architecture is not realistic due to the enormous diversity in vehicles, sensors and applications. As an alternative, this work presents a methodology that can be used to effectively come up with an implementation to build a consistent model of a vehicle’s surroundings. The methodology is accompanied by a software architecture. This combination minimizes the effort required to update the multisensor data fusion system whenever sensors or applications are added or replaced. A series of real-world experiments involving different sensors and algorithms demonstrates the methodology and the software architecture.

  8. Predicting psychopharmacological drug effects on actual driving performance (SDLP) from psychometric tests measuring driving-related skills

    OpenAIRE

    Verster, Joris C.; Roth, Thomas

    2011-01-01

    Rationale There are various methods to examine driving ability. Comparisons between these methods and their relationship with actual on-road driving is often not determined. Objective The objective of this study was to determine whether laboratory tests measuring driving-related skills could adequately predict on-the-road driving performance during normal traffic. Methods Ninety-six healthy volunteers performed a standardized on-the-road driving test. Subjects were instructed to drive with a ...

  9. Effects of alcohol on automated and controlled driving performances.

    Science.gov (United States)

    Berthelon, Catherine; Gineyt, Guy

    2014-05-01

    Alcohol is the most frequently detected substance in fatal automobile crashes, but its precise mode of action is not always clear. The present study was designed to establish the influence of blood alcohol concentration as a function of the complexity of the scenarios. Road scenarios implying automatic or controlled driving performances were manipulated in order to identify which behavioral parameters were deteriorated. A single blind counterbalanced experiment was conducted on a driving simulator. Sixteen experienced drivers (25.3 ± 2.9 years old, 8 men and 8 women) were tested with 0, 0.3, 0.5, and 0.8 g/l of alcohol. Driving scenarios varied: road tracking, car following, and an urban scenario including events inspired by real accidents. Statistical analyses were performed on driving parameters as a function of alcohol level. Automated driving parameters such as standard deviation of lateral position measured with the road tracking and car following scenarios were impaired by alcohol, notably with the highest dose. More controlled parameters such as response time to braking and number of crashes when confronted with specific events (urban scenario) were less affected by the alcohol level. Performance decrement was greater with driving scenarios involving automated processes than with scenarios involving controlled processes.

  10. Effect of component aging on PWR control rod drive systems

    International Nuclear Information System (INIS)

    Grove, E.; Gunther, W.; Sullivan, K.

    1992-01-01

    An aging assessment of PWR control rod drive (CRD) systems has been completed as part of the US NRC Nuclear Plant Aging Research (NPAR) Program. The design, construction, maintenance, and operation of the Babcock ampersand Wilcox (B ampersand W), Combustion Engineering (CE), and Westinghouse (W) systems were evaluated to determine the potential for degradation as each system ages. Operating experience data were evaluated to identify the predominant failure modes, causes, and effects. This, coupled with an assessment of the materials of construction and operating environment, demonstrate that each design is subject to degradation, which if left unchecked, could affect its safety function as the plant ages. An industry survey, conducted with the assistance of EPRI and NUMARC, identified current CRD system maintenance and inspection practices. The results of this survey indicate that some plants have performed system modifications, replaced components, or augmented existing preventive maintenance practices in response to system aging. The survey results also supported the operating experience data, which concluded that the timely replacement of degraded components, prior to failure, was not always possible using existing condition monitoring techniques. The recommendations presented in this study also include a discussion of more advanced monitoring techniques, which provide trendable results capable of detecting aging

  11. Jack-of-all-trades effects drive biodiversity–ecosystem multifunctionality relationships in European forests

    Science.gov (United States)

    van der Plas, Fons; Manning, Peter; Allan, Eric; Scherer-Lorenzen, Michael; Verheyen, Kris; Wirth, Christian; Zavala, Miguel A.; Hector, Andy; Ampoorter, Evy; Baeten, Lander; Barbaro, Luc; Bauhus, Jürgen; Benavides, Raquel; Benneter, Adam; Berthold, Felix; Bonal, Damien; Bouriaud, Olivier; Bruelheide, Helge; Bussotti, Filippo; Carnol, Monique; Castagneyrol, Bastien; Charbonnier, Yohan; Coomes, David; Coppi, Andrea; Bastias, Cristina C.; Muhie Dawud, Seid; De Wandeler, Hans; Domisch, Timo; Finér, Leena; Gessler, Arthur; Granier, André; Grossiord, Charlotte; Guyot, Virginie; Hättenschwiler, Stephan; Jactel, Hervé; Jaroszewicz, Bogdan; Joly, François-Xavier; Jucker, Tommaso; Koricheva, Julia; Milligan, Harriet; Müller, Sandra; Muys, Bart; Nguyen, Diem; Pollastrini, Martina; Raulund-Rasmussen, Karsten; Selvi, Federico; Stenlid, Jan; Valladares, Fernando; Vesterdal, Lars; Zielínski, Dawid; Fischer, Markus

    2016-01-01

    There is considerable evidence that biodiversity promotes multiple ecosystem functions (multifunctionality), thus ensuring the delivery of ecosystem services important for human well-being. However, the mechanisms underlying this relationship are poorly understood, especially in natural ecosystems. We develop a novel approach to partition biodiversity effects on multifunctionality into three mechanisms and apply this to European forest data. We show that throughout Europe, tree diversity is positively related with multifunctionality when moderate levels of functioning are required, but negatively when very high function levels are desired. For two well-known mechanisms, ‘complementarity' and ‘selection', we detect only minor effects on multifunctionality. Instead a third, so far overlooked mechanism, the ‘jack-of-all-trades' effect, caused by the averaging of individual species effects on function, drives observed patterns. Simulations demonstrate that jack-of-all-trades effects occur whenever species effects on different functions are not perfectly correlated, meaning they may contribute to diversity–multifunctionality relationships in many of the world's ecosystems. PMID:27010076

  12. Study on Awakening Effect by Fragrance Presentation Against Drowsy Driving and Construction of Fragrance Presentation System

    Science.gov (United States)

    Kakamu, Yuki; Yoshikawa, Masahito; Shimizu, Takayuki; Yanagida, Yasuyuki; Nakano, Tomoaki; Yamamoto, Shin; Yamada, Muneo

    Traffic accidents caused by drowsy driving never disappear and easily result in fatal crash when heavy vehicle is involved. General methods to prevent drowsy driving are caution-advisory indicators and alarm sounds. However visual and auditory information are excessive enough to alert drivers. This study aims to focus on olfactory stimuli, which do not provoke interference with driving actions, and examine the effectiveness in combating drowsiness. Changing type of scent, we performed investigations on the effectiveness of each countermeasure to remain alert against drowsy driving.

  13. Effect of pile-driving sounds on the survival of larval fish

    NARCIS (Netherlands)

    Bolle, L.J.; Jong, C.A.F. de; Bierman, S.M.; Beek, P.J.G. van van; Wessels, P.W.; Blom, E.; Damme, C.J.G. van; Winter, H.V.; Dekeling, R.P.A.

    2016-01-01

    Concern exists about the potential effects of pile-driving sounds on fish, but evidence is limited, especially for fish larvae. A device was developed to expose larvae to accurately reproduced pile-driving sounds. Controlled exposure experiments were carried out to examine the lethal effects in

  14. Driving with music : Effects on arousal and performance

    NARCIS (Netherlands)

    Unal, Ayca Berfu; de Waard, Dick; Epstude, Kai; Steg, Linda

    2013-01-01

    In the current study, we aimed at exploring the influence of music on driving performance, arousal and mental effort while carrying out a monotonous car-following task in a low-complexity traffic setting. Participants (N = 47) were randomly assigned to loud and moderate volume music groups, and

  15. Effect of sleep deprivation on driving safety in housestaff.

    Science.gov (United States)

    Marcus, C L; Loughlin, G M

    1996-12-01

    Sleep deprivation is known to affect driving safety. Housestaff (HS) are routinely sleep-deprived when on call. We hypothesized that this would affect their driving. We therefore administered questionnaires regarding driving to 70 pediatric HS, who were on call every fourth night, and to 85 faculty members (FAC), who were rarely disturbed at night. HS were questioned about events during their residency, and FAC were questioned about events during the preceding three years. There was an 87% response rate for each group. HS slept 2.7 +/- 0.9 (SD) hours when on call vs 7.2 +/- 0.8 hours when not on call (p < 0.001). 44% of HS had fallen asleep when stopped at a light, vs 12.5% FAC (p < 0.001). 23% of HS had fallen asleep while driving vs. 8% FAC (ns). A total of 49% of HS had fallen asleep at the wheel; 90% of these events occurred post-call. In contrast, only 13% of FAC had fallen asleep at the wheel (p < 0.001). HS had received a total of 25 traffic citations for moving violations vs. 15 for FAC and were involved in 20 motor vehicle accidents vs. 11 for FAC. One traffic citation clearly resulted from HS falling asleep at the wheel vs. none for FAC. We conclude that HS frequently fall asleep when driving post-call. We speculate that current HS work schedules may place some HS at risk for injury to themselves and others. Further study, using prospectively objective measures is indicated.

  16. Practice makes better - Learning effects of driving with a multi-stage collision warning.

    Science.gov (United States)

    Winkler, Susann; Kazazi, Juela; Vollrath, Mark

    2018-02-21

    Advanced driver assistance systems like (forward) collision warnings can increase traffic safety. As safety-critical situations (especially in urban traffic) can be diverse, integrated adaptive systems (such as multi-stage warnings) need to be developed and examined in a variety of use cases over time instead of the more common approach of testing only one-time effectiveness in the most relevant use case. Thus, this driving simulator experiment investigated a multi-stage collision warning in partially repetitive trials (T) of various safety-critical situations (scenarios confronting drivers with hazards in form of pedestrians, obstacles or preceding vehicles). Its output adapted according to the drivers' behavior in two warning stages (W1 - warning for moderate deceleration in less critical situations; W2 - urgent warning for strong, fast braking in more critical situations). To analyze how much drivers benefit from the assistance when allowed practice with it, the driving behavior and subjective ratings of 24 participants were measured over four trials. They comprised a baseline without assistance (T1) and three further trials with assistance - a learning phase repeating the scenarios from T1 twice (T2 + T3) and a concluding transfer drive with new scenarios (T4). As expected, the situation criticality in the urgent warning (W2) scenarios was rated higher than in the warning (W1) scenarios. While the brake reaction time differed more between the W1 scenarios, the applied brake force differed more between the W2 scenarios. However, the scenario factor often interacted with the trial factor. Since in later warning stages reaction time reductions become finite, the reaction strength gains importance. Overall the drivers benefited from the assistance. Both warning stages led to faster brake reactions (of similar strength) in all three assisted trials compared to the baseline, which additionally improved successively over time (T1-T3, T1 vs. T4, T2 vs. T4

  17. Effective Retention Strategies for Diverse Employees.

    Science.gov (United States)

    Musser, Linda R.

    2001-01-01

    Discusses methods to determine why employees leave or stay, based on experiences at Pennsylvania State University libraries. Considers retention tools that work best to retain diverse employees, including mentoring, networking, career and learning opportunities, balance between work and home life, a welcoming climate, and support for research.…

  18. Soil Parameters Drive the Structure, Diversity and Metabolic Potentials of the Bacterial Communities Across Temperate Beech Forest Soil Sequences.

    Science.gov (United States)

    Jeanbille, M; Buée, M; Bach, C; Cébron, A; Frey-Klett, P; Turpault, M P; Uroz, S

    2016-02-01

    Soil and climatic conditions as well as land cover and land management have been shown to strongly impact the structure and diversity of the soil bacterial communities. Here, we addressed under a same land cover the potential effect of the edaphic parameters on the soil bacterial communities, excluding potential confounding factors as climate. To do this, we characterized two natural soil sequences occurring in the Montiers experimental site. Spatially distant soil samples were collected below Fagus sylvatica tree stands to assess the effect of soil sequences on the edaphic parameters, as well as the structure and diversity of the bacterial communities. Soil analyses revealed that the two soil sequences were characterized by higher pH and calcium and magnesium contents in the lower plots. Metabolic assays based on Biolog Ecoplates highlighted higher intensity and richness in usable carbon substrates in the lower plots than in the middle and upper plots, although no significant differences occurred in the abundance of bacterial and fungal communities along the soil sequences as assessed using quantitative PCR. Pyrosequencing analysis of 16S ribosomal RNA (rRNA) gene amplicons revealed that Proteobacteria, Acidobacteria and Bacteroidetes were the most abundantly represented phyla. Acidobacteria, Proteobacteria and Chlamydiae were significantly enriched in the most acidic and nutrient-poor soils compared to the Bacteroidetes, which were significantly enriched in the soils presenting the higher pH and nutrient contents. Interestingly, aluminium, nitrogen, calcium, nutrient availability and pH appeared to be the best predictors of the bacterial community structures along the soil sequences.

  19. Land use change has stronger effects on functional diversity than taxonomic diversity in tropical Andean hummingbirds.

    Science.gov (United States)

    Tinoco, Boris A; Santillán, Vinicio E; Graham, Catherine H

    2018-03-01

    Land use change modifies the environment at multiple spatial scales, and is a main driver of species declines and deterioration of ecosystem services. However, most of the research on the effects of land use change has focused on taxonomic diversity, while functional diversity, an important predictor of ecosystem services, is often neglected. We explored how local and landscape scale characteristics influence functional and taxonomic diversity of hummingbirds in the Andes Mountains in southern Ecuador. Data was collected in six landscapes along a land use gradient, from an almost intact landscape to one dominated by cattle pastures. We used point counts to sample hummingbirds from 2011 to 2012 to assessed how local factors (i.e., vegetation structure, flowering plants richness, nectar availability) and landscape factors (i.e., landscape heterogeneity, native vegetation cover) influenced taxonomic and functional diversity. Then, we analyzed environment - trait relationships (RLQ test) to explore how different hummingbird functional traits influenced species responses to these factors. Taxonomic and functional diversity of hummingbirds were positively associated with landscape heterogeneity but only functional diversity was positively related to native vegetation coverage. We found a weak response of taxonomic and functional diversity to land use change at the local scale. Environment-trait associations showed that body mass of hummingbirds likely influenced species sensitivity to land use change. In conclusion, landscape heterogeneity created by land use change can positively influence hummingbird taxonomic and functional diversity; however, a reduction of native vegetation cover could decrease functional diversity. Given that functional diversity can mediate ecosystem services, the conservation of native vegetation cover could play a key role in the maintenance of hummingbird pollination services in the tropical Andes. Moreover, there are particular functional

  20. Alcohol effects on simulated driving performance and self-perceptions of impairment in DUI offenders.

    Science.gov (United States)

    Van Dyke, Nicholas; Fillmore, Mark T

    2014-12-01

    Drivers with a history of driving under the influence (DUI) of alcohol self-report heightened impulsivity and display reckless driving behaviors as indicated by increased rates of vehicle crashes, moving violations, and traffic tickets. Such poor behavioral self-regulation could also increase sensitivity to the disruptive effects of alcohol on driving performance. The present study examined the degree to which DUI drivers display an increased sensitivity to the acute impairing effects of alcohol on simulated driving performance and overestimate their driving fitness following alcohol consumption. Adult drivers with a history of DUI and a demographically matched group of drivers with no history of DUI (controls) were tested following a 0.65 g/kg alcohol and a placebo. Results indicated that alcohol impaired several measures of driving performance, and there was no difference between DUI offenders and controls in these impairments. However, following alcohol, DUI drivers self-reported a greater ability and willingness to drive compared with controls. These findings indicate that drivers with a history of DUI might perceive themselves as more fit to drive after drinking, which could play an important role in their decisions to drink and drive. PsycINFO Database Record (c) 2014 APA, all rights reserved.

  1. The effects of music on time perception and performance of a driving game.

    Science.gov (United States)

    Cassidy, G G; Macdonald, R A R

    2010-12-01

    There is an established and growing body of evidence highlighting that music can influence behavior across a range of diverse domains (Miell, MacDonald, & Hargreaves 2005). One area of interest is the monitoring of "internal timing mechanisms", with features such as tempo, liking, perceived affective nature and everyday listening contexts implicated as important (North & Hargreaves, 2008). The current study addresses these issues by comparing the effects of self-selected and experimenter-selected music (fast and slow) on actual and perceived performance of a driving game activity. Seventy participants completed three laps of a driving game in seven sound conditions: (1) silence; (2) car sounds; (3) car sounds with self-selected music, and car sounds with experimenter-selected music; (4) high-arousal (70 bpm); (5) high-arousal (130 bpm); (6) low-arousal (70 bpm); and (7) low-arousal (130 bpm) music. Six performance measures (time, accuracy, speed, and retrospective perception of these), and four experience measures (perceived distraction, liking, appropriateness and enjoyment) were taken. Exposure to self-selected music resulted in overestimation of elapsed time and inaccuracy, while benefiting accuracy and experience. In contrast, exposure to experimenter-selected music resulted in poorest performance and experience. Increasing the tempo of experimenter-selected music resulted in faster performance and increased inaccuracy for high-arousal music, but did not impact experience. It is suggested that personal meaning and subjective associations connected to self-selected music promoted increased engagement with the activity, overriding detrimental effects attributed to unfamiliar, less liked and less appropriate experimenter-selected music. © 2010 The Authors. Scandinavian Journal of Psychology © 2010 The Scandinavian Psychological Associations.

  2. Diversity begets diversity? The effects of board composition on the appointment and success of women CEOs.

    Science.gov (United States)

    Cook, Alison; Glass, Christy

    2015-09-01

    Previous research on the effects of leadership diversity on firm outcomes has produced inconsistent and inconclusive findings. While some scholars argue that diversity increases organizational equity and enhances performance, others argue that diversity increases conflict, reduces cooperation and harms performance. This study tests the impact of a variety of compositional factors on firm outcomes. Specifically, we analyze whether and how board composition affects the advancement and mobility of women CEOs and firm performance. Our analysis relies on a unique data set of all Chief Executive Officers (CEOs) and Board of Directors (BODs) in Fortune 500 companies over a ten-year period. We find a marginally significant positive relationship between board diversity and the likelihood of a woman being appointed CEO. We further find that board diversity significantly and positively influences the post-promotion success of women CEOs. Our findings suggest that board composition is critical for the appointment and success of women CEOs, and increasing board diversity should be central to any organizational diversity efforts. Copyright © 2015 Elsevier Inc. All rights reserved.

  3. Dexamphetamine and alcohol effects in simulated driving and cognitive task performance

    NARCIS (Netherlands)

    Martens, Marieke Hendrikje; Simons, Ries; Ramaekers, Jan

    2011-01-01

    This study assessed the effects of dexamphetamine with and without alcohol on simulated driving and cognitive tasks. 18 subjects participated in all 4 conditions: 10 mg dexamphetamine and 0.8g/kg alcohol, 10 mg dexamphetamine only, 0.8g/kg alcohol only, and a placebo control condition. A driving

  4. The eco-driving effect of electric vehicles compared to conventional gasoline vehicles

    Directory of Open Access Journals (Sweden)

    Hideki Kato

    2016-10-01

    Full Text Available Eco-driving is attractive to the public, not only users of internal-combustion-engine vehicles (ICEVs including hybrid electric vehicles (HEVs but also users of electric vehicles (EVs have interest in eco-driving. In this context, a quantitative evaluation of eco-driving effect of EVs was conducted using a chassis dynamometer (C/D with an “eco-driving test mode.” This mode comprised four speed patterns selected from fifty-two real-world driving datasets collected during an eco-driving test-ride event. The four patterns had the same travel distance (5.2 km, but showed varying eco-driving achievement levels. Three ICEVs, one HEV and two EVs were tested using a C/D. Good linear relationships were found between the eco-driving achievement level and electric or fuel consumption rate of all vehicles. The reduction of CO2 emissions was also estimated. The CO2-reduction rates of the four conventional (including hybrid vehicles were 10.9%–12.6%, while those of two types of EVs were 11.7%–18.4%. These results indicate that the eco-driving tips for conventional vehicles are effective to not only ICEVs and HEVs but also EVs. Furthermore, EVs have a higher potential of eco-driving effect than ICEVs and HEVs if EVs could maintain high energy conversion efficiency at low load range. This study is intended to support the importance of the dissemination of tools like the intelligent speed adaptation (ISA to obey the regulation speed in real time. In the future, also in the development and dissemination of automated driving systems, the viewpoint of achieving the traveling purpose with less kinetic energy would be important.

  5. Assessing the Effects of Grass Roots Drunk Driving Prevention Programs: First Facts. Report from the Drunk Driving Prevention Project.

    Science.gov (United States)

    Ungerleider, Steven; And Others

    While drunk driving has become widely recognized as a serious social problem with deadly consequences, no systematic research has been undertaken to identify the principal components of service delivery programs offered by citizen action groups in the drinking and driving movement. Mothers Against Drunk Driving (MADD), founded in 1980, now has a…

  6. Are Tree Species Diversity and Genotypic Diversity Effects on Insect Herbivores Mediated by Ants?

    Directory of Open Access Journals (Sweden)

    María José Campos-Navarrete

    Full Text Available Plant diversity can influence predators and omnivores and such effects may in turn influence herbivores and plants. However, evidence for these ecological feedbacks is rare. We evaluated if the effects of tree species (SD and genotypic diversity (GD on the abundance of different guilds of insect herbivores associated with big-leaf mahogany (Swietenia macrophylla were contingent upon the protective effects of ants tending extra-floral nectaries of this species. This study was conducted within a larger experiment consisting of mahogany monocultures and species polycultures of four species and -within each of these two plot types- mahogany was represented by either one or four maternal families. We selected 24 plots spanning these treatment combinations, 10 mahogany plants/plot, and within each plot experimentally reduced ant abundance on half of the selected plants, and surveyed ant and herbivore abundance. There were positive effects of SD on generalist leaf-chewers and sap-feeders, but for the latter group this effect depended on the ant reduction treatment: SD positively influenced sap-feeders under ambient ant abundance but had no effect when ant abundance was reduced; at the same time, ants had negative effects on sap feeders in monoculture but no effect in polyculture. In contrast, SD did not influence specialist stem-borers or leaf-miners and this effect was not contingent upon ant reduction. Finally, GD did not influence any of the herbivore guilds studied, and such effects did not depend on the ant treatment. Overall, we show that tree species diversity influenced interactions between a focal plant species (mahogany and ants, and that such effects in turn mediated plant diversity effects on some (sap-feeders but not all the herbivores guilds studied. Our results suggest that the observed patterns are dependent on the combined effects of herbivore identity, diet breadth, and the source of plant diversity.

  7. Effect of Plant Diversity on Diversity and Abundance of Arthropods in Winter Wheat Fields

    Directory of Open Access Journals (Sweden)

    A Khodashenas

    2011-02-01

    Full Text Available Abstract Plant biomass and diversity play an important role in enhancing of biodiversity of other trophic levels, specially arthropods in terrestrial ecosystems. In order to determine the effects of plants on diversity and abundance of arthropods, a study was carried out in three regions of Razavi and northern Khorasan provinces, Shirvan, Mashhad and Gonabad. In each region, high and low input fields of winter wheat and a natural system for comparison were selected. In ripening stage of wheat growth (90 stage of Zadoks, sampling was done by use of quadrate in each system with five replications. Plants in each quadrate were counted and species richness of plants was determined. Insect sampling was done by sweep net from surface of plants, then species richness and abundance of collected insects were determined. As a result, agricultural practices decreased plant species richness but diversity and abundance of insects and spiders increased in agricultural systems. Our finding revealed that abundance of insects and spiders were not affected by plant species richness and plant biomass was the main factor affecting on species richness and abundance of insects, spiders and beneficial insects. Therefore, decreasing plant species richness that arose from agricultural practices doesn’t effect on arthropods diversity and abundance and doesn’t decrease sustainability of agricultural systems. Irregular use of chemical inputs, specially pesticides, is the main factor to decreasing of plants and arthropods species richness in agricultural systems. Keywords: Plant diversity, Arthropod diversity, Arthropod abundance, Plant-insect interactions, Agricultural systems

  8. Effects of Diversity Experiences on Critical Thinking Skills: Who Benefits?

    Science.gov (United States)

    Loes, Chad; Pascarella, Ernest; Umbach, Paul

    2012-01-01

    This study analyzed data from the Wabash National Study of Liberal Arts Education to estimate the unique effects of exposure to classroom diversity and involvement in interactional diversity on growth in critical thinking skills during the first year of college. Net of important confounding influences, neither classroom nor interactional diversity…

  9. Offense History and the Effectiveness of Juvenile Diversion Programs.

    Science.gov (United States)

    Osgood, D. Wayne; And Others

    Some evaluations have concluded that diversion programs for juvenile offenders (programs intended as community-based alternatives to formal justice dispositions) reduce recidivism only among youths with the least serious offense histories. To investigate the relationship of offense history to program effectiveness, three diversion programs were…

  10. Repeated-dose effects of mequitazine, cetirizine and dexchlorpheniramine on driving and psychomotor performance.

    Science.gov (United States)

    Theunissen, Eef L; Vermeeren, Annemiek; Ramaekers, Johannes G

    2006-01-01

    Previous studies have demonstrated that the antihistamines mequitazine, cetirizine and dexchlorpheniramine produce mild sedation after single doses. It is unknown, however, whether acute sedation persists after repeated dosing. Therefore, this study assessed the effects of repeated dosing of these antihistamines on driving and psychomotor performance. Sixteen healthy volunteers were treated with mequitazine 10 mg q.a.m., cetirizine 10 mg q.a.m., dexchlorpheniramine Repetab 6 mg b.i.d. and placebo for four separate 8-day periods. Drug effects were assessed on days 1 and 8 using on-the-road driving tests (highway driving and car following), psychomotor tests (tracking and divided attention) and subjective questionnaires. Dexchlorpheniramine and mequitazine significantly impaired driving performance on the highway driving test on the first day; dexchlorpheniramine increased Standard Deviation of Lateral Position by 2 cm [95% confidence interval (CI) 0.5, 3.8] and mequitazine by 2.5 cm (CI 1.0, 4.3). These effects on driving performance disappeared after 8 days of treatment. No effect of treatment was found on car following, tracking and divided attention. Although subjective ratings confirmed that subjects knew their driving had been impaired in the mequitazine and dexchlorpheniramine condition after completion of the highway driving test on day 1, they did not expect their driving to be affected before the start of the test. Cetirizine did not impair performance on any of the tests. Single doses of mequitazine 10 mg and dexchlorpheniramine Repetab 6 mg cause mild driving impairment. However, when taken over several days, the impairing effect wears off, possibly as a result of tolerance.

  11. The effects of driver identity on driving safety in a retrospective feedback system.

    Science.gov (United States)

    Zhao, Guozhen; Wu, Changxu

    2012-03-01

    Retrospective feedback that provides detailed information on a driver's performance in critical driving situations at the end of a trip enhances his/her driving behaviors and safe driving habits. Although this has been demonstrated by a previous study, retrospective feedback can be further improved and applied to non-critical driving situations, which is needed for transportation safety. To propose a new retrospective feedback system that uses driver identity (i.e., a driver's name) and to experimentally study its effects on measures of driving performance and safety in a driving simulator. We conducted a behavioral experimental study with 30 participants. "Feedback type" was a between-subject variable with three conditions: no feedback (control group), feedback without driver identity, and feedback with driver identity. We measured multiple aspects of participants' driving behavior. To control for potential confounds, factors that were significantly correlated with driving behavior (e.g., age and driving experience) were all entered as covariates into a multivariate analysis of variance. To examine the effects of speeding on collision severity in driving simulation studies, we also developed a new index - momentum of potential collision - with a set of equations. Subjects who used a feedback system with driver identity had the fewest speeding violations and central-line crossings, spent the least amount of time speeding and crossing the central line, had the lowest speeding and central-line crossing magnitude, ran the fewest red lights, and had the smallest momentum of potential collision compared to the groups with feedback without driver identity and without feedback (control group). The new retrospective feedback system with driver identity has the potential to enhance a person's driving safety (e.g., speeding, central-line crossing, momentum of potential collision), which is an indication of the valence of one's name in a feedback system design. Copyright

  12. Modeling of finite aspect ratio effects on current drive

    International Nuclear Information System (INIS)

    Wright, J.C.; Phillips, C.K.

    1996-01-01

    Most 2D RF modeling codes use a parameterization of current drive efficiencies to calculate fast wave driven currents. This parameterization assumes a uniform diffusion coefficient and requires a priori knowledge of the wave polarizations. These difficulties may be avoided by a direct calculation of the quasilinear diffusion coefficient from the Kennel-Englemann form with the field polarizations calculated by a full wave code. This eliminates the need to use the approximation inherent in the parameterization. Current profiles are then calculated using the adjoint formulation. This approach has been implemented in the FISIC code. The accuracy of the parameterization of the current drive efficiency, η, is judged by a comparison with a direct calculation: where χ is the adjoint function, ε is the kinetic energy, and rvec Γ is the quasilinear flux. It is shown that for large aspect ratio devices (ε → 0), the parameterization is nearly identical to the direct calculation. As the aspect ratio approaches unity, visible differences between the two calculations appear

  13. Effects of personality on risky driving behavior and accident involvement for Chinese drivers.

    Science.gov (United States)

    Yang, Jiaoyan; Du, Feng; Qu, Weina; Gong, Zhun; Sun, Xianghong

    2013-01-01

    Motor vehicle accidents are the leading cause of injury-related fatalities in China and pose the most serious threat to driving safety. Driver personality is considered as an effective predictor for risky driving behavior and accident liability. Previous studies have focused on the relationship between personality and risky driving behavior, but only a few of them have explored the effects of personality variables on accident involvement. In addition, few studies have examined the effects of personality on Chinese drivers' risky driving and accident involvement. The present study aimed to examine the effects of personality variables on Chinese drivers' unsafe driving behaviors and accident involvement. Two hundred and twenty-four Chinese drivers aged 20 to 50 were required to complete questionnaires assessing their personality traits (anger, sensation-seeking, altruism, and normlessness), risky driving behaviors (aggressive violations, ordinary violations), and accident involvement (all accidents, serious accidents, at-fault accidents). Multivariate regression analyses, adjusting for gender, age, and overall mileage, were conducted to identify the personality traits related to risky driving behaviors and accident involvement. Participants' personality traits were found to be significantly correlated with both risky driving behavior and accident involvement. Specifically, the traits of anger and normlessness were effective predictors for aggressive violations. The traits of anger, sensation-seeking, normlessness, and altruism were effective predictors for ordinary violations. Moreover, altruism and normlessness were significant predictors for the total number of accidents participants had during the past 3 years. Consistent with previous studies, the present study revealed that personality traits play an important role in predicting Chinese drivers' risky driving behaviors. In addition, Chinese drivers' personality characteristics were also associated with accident

  14. Does the parasite-mediated selection drive the MHC class IIB diversity in wild populations of European chub (Squalius cephalus)?

    Science.gov (United States)

    Seifertová, Mária; Jarkovský, Jiří; Šimková, Andrea

    2016-04-01

    The genes of major histocompatibility complex (MHC) provide an excellent opportunity to study host-parasite relationships because they are expected to evolve in response to parasites and variation in parasite communities. In this study, we investigated the potential role of parasite-mediated selection acting on MHC class IIB (DAB) genes in European chub (Squalius cephalus) natural populations. We found significant differences between populations in metazoan parasites, neutral and adaptive genetic diversities. The analyses based on pairwise data revealed that populations with dissimilar MHC allelic profiles were geographically distant populations with significantly different diversity in microsatellites and a dissimilar composition of parasite communities. The results from the generalized estimating equations method (GEE) on the level of individuals revealed that metazoan parasite load in European chub was influenced by the diversity of DAB alleles as well as by the diversity of neutral genetic markers and host traits reflecting condition and immunocompetence. The multivariate co-inertia analysis showed specific associations between DAB alleles and parasite species. DAB1-like alleles were more involved in associations with ectoparasites, while DAB3-like alleles were positively associated with endoparasites which could suggest potential differences between DAB genes caused by different selection pressure. Our study revealed that parasite-mediated selection is not the only variable affecting MHC diversity in European chub; however, we strongly support the role of neutral processes as the main driver of DAB diversity across populations. In addition, our study contributes to the understanding of the evolution of MHC genes in wild living fish.

  15. Effects of landscape fragmentation on genetic diversity of Stipa ...

    African Journals Online (AJOL)

    STORAGESEVER

    2009-08-04

    Aug 4, 2009 ... Effects of landscape fragmentation on genetic diversity of Stipa krylovii ..... nation plant tends to anemophily, this pollination mode enable it to have the .... sity on newly isolated tropical islands: a test of a null hypothesis and.

  16. Institutions and Cultural Diversity: Effects of Democratic and Propaganda Processes on Local Convergence and Global Diversity.

    Science.gov (United States)

    Ulloa, Roberto; Kacperski, Celina; Sancho, Fernando

    2016-01-01

    In a connected world where people influence each other, what can cause a globalized monoculture, and which measures help to preserve the coexistence of cultures? Previous research has shown that factors such as homophily, population size, geography, mass media, and type of social influence play important roles. In the present paper, we investigate for the first time the impact that institutions have on cultural diversity. In our first three studies, we extend existing agent-based models and explore the effects of institutional influence and agent loyalty. We find that higher institutional influence increases cultural diversity, while individuals' loyalty to their institutions has a small, preserving effect. In three further studies, we test how bottom-up and top-down processes of institutional influence impact our model. We find that bottom-up democratic practices, such as referenda, tend to produce convergence towards homogeneity, while top-down information dissemination practices, such as propaganda, further increase diversity. In our last model--an integration of bottom-up and top-down processes into a feedback loop of information--we find that when democratic processes are rare, the effects of propaganda are amplified, i.e., more diversity emerges; however, when democratic processes are common, they are able to neutralize or reverse this propaganda effect. Importantly, our models allow for control over the full spectrum of diversity, so that a manipulation of our parameters can result in preferred levels of diversity, which will be useful for the study of other factors in the future. We discuss possible mechanisms behind our results, applications, and implications for political and social sciences.

  17. Driving monotonous routes in a train simulator: the effect of task demand on driving performance and subjective experience.

    Science.gov (United States)

    Dunn, Naomi; Williamson, Ann

    2012-01-01

    Although monotony is widely recognised as being detrimental to performance, its occurrence and effects are not yet well understood. This is despite the fact that task-related characteristics, such as monotony and low task demand, have been shown to contribute to performance decrements over time. Participants completed one of two simulated train-driving scenarios. Both were highly monotonous and differed only in terms of the level of cognitive demand required (i.e. low demand or high demand). These results highlight the seriously detrimental effects of the combination of monotony and low task demands and clearly show that even a relatively minor increase in cognitive demand can mitigate adverse monotony-related effects on performance for extended periods of time. Monotony is an inherent characteristic of transport industries, including rail, aviation and road transport, which can have adverse impact on safety, reliability and efficiency. This study highlights possible strategies for mitigating these adverse effects. Practitioner Summary: This study provides evidence for the importance of cognitive demand in mitigating monotony-related effects on performance. The results have clear implications for the rapid onset of performance deterioration in low demand monotonous tasks and demonstrate that these detrimental performance effects can be overcome with simple solutions, such as making the task more cognitively engaging.

  18. Study on the effect of driving cycles on energy efficiency of electric vehicles

    Energy Technology Data Exchange (ETDEWEB)

    Ji Fenzhu; Xu Licong [School of Transportation Science and Engineering of Beihang Univ., BJ (China); Wu Zhixin [Tianjin Qing Yuan Electric Vehicle Corp. Ltd., TJ (China)

    2009-07-01

    The energy usage efficiency of electric vehicles (EVS) and evaluation index of electromotor efficiency were studied. The idea of ''interval usage percentage of energy efficiency'' and ''exertion degree of energy efficiency'' of electromotor was brought forward. The effect of driving cycles on the distribution of running status of electromotor and its efficiency was investigated. The electromotor efficiency and the variety trend of average driving force at different driving cycles were discussed. Based on several typical domestic and foreign driving cycles, the exertion degree of energy efficiency and the whole efficiency of power train on some types of EVS were analyzed and calculated. The result indicates that there is a difference of 9.64% in exertion degree of energy efficiency of electromotor at different driving cycles. The efficiency distribution of electromotor and control system is different, and the average driving force is different, too. That cause the great variety in driving range. The idiographic reference data are provided to the establishment of driving cycles' criterion of EVS in our country. (orig.)

  19. Subharmonic emissions from microbubbles: effect of the driving pulse shape.

    Science.gov (United States)

    Biagi, Elena; Breschi, Luca; Vannacci, Enrico; Masotti, Leonardo

    2006-11-01

    The aims of this work are to investigate the response of the ultrasonic contrast agents (UCA) insonified by different arbitrary-shaped pulses at different acoustic pressures and concentration of the contrast agent focusing on subharmonic emission. A transmission setup was developed in order to insonify the contrast agent contained in a measurement chamber. The transmitted ultrasonic signals were generated by an arbitrary wave generator connected to a linear power amplifier able to drive a single-element transducer. The transmitted ultrasonic pulses that passed through the contrast agent-filled chamber were received by a second transducer or a hydrophone aligned with the first one. The radio frequency (RF) signals were acquired by fast echographic multiparameters multi-image novel apparatus (FEMMINA), which is an echographic platform able to acquire ultrasonic signals in a real-time modality. Three sets of ultrasonic signals were devised in order to evaluate subharmonic response of the contrast agent respect with sinusoidal burst signals used as reference pulses. A decreasing up to 30 dB in subharmonic response was detected for a Gaussian-shaped pulse; differences in subharmonic emission up to 21 dB were detected for a composite pulse (two-tone burst) for different acoustic pressures and concentrations. Results from this experimentation demonstrated that the transmitted pulse shape strongly affects subharmonic emission in spite of a second harmonic one. In particular, the smoothness of the initial portion of the shaped pulses can inhibit subharmonic generation from the contrast agents respect with a reference sinusoidal burst signal. It also was shown that subharmonic generation is influenced by the amplitude and the concentration of the contrast agent for each set of the shaped pulses. Subharmonic emissions that derive from a nonlinear mechanism involving nonlinear coupling among different oscillation modes are strongly affected by the shape of the ultrasonic

  20. Internet use among urban Malaysians: Network diversity effects

    Directory of Open Access Journals (Sweden)

    De Rycker Antoon

    2017-01-01

    Full Text Available This study examines social network diversity in urban areas relative to residents’ usage of information and communication technologies (ICTs. Individual-level variation in social network diversity was measured using position generator data collected as part of a survey conducted in Malaysia’s Klang Valley (N = 808. Regression analyses were performed to assess the extent to which network diversity is related to ICTs. We find that most ICTs have a negative effect on diversity. Only frequent use of the Internet at work, mobile access to the Internet, and reading online news or blogs contribute positively to diversity. Findings support both a tendency toward ‘networked individualism’ and the more recent ‘glocalization’ thesis that some ICTs may also afford participation within local space rather than only across distant space.

  1. Driving While Interacting With Google Glass: Investigating the Combined Effect of Head-Up Display and Hands-Free Input on Driving Safety and Multitask Performance.

    Science.gov (United States)

    Tippey, Kathryn G; Sivaraj, Elayaraj; Ferris, Thomas K

    2017-06-01

    This study evaluated the individual and combined effects of voice (vs. manual) input and head-up (vs. head-down) display in a driving and device interaction task. Advances in wearable technology offer new possibilities for in-vehicle interaction but also present new challenges for managing driver attention and regulating device usage in vehicles. This research investigated how driving performance is affected by interface characteristics of devices used for concurrent secondary tasks. A positive impact on driving performance was expected when devices included voice-to-text functionality (reducing demand for visual and manual resources) and a head-up display (HUD) (supporting greater visibility of the driving environment). Driver behavior and performance was compared in a texting-while-driving task set during a driving simulation. The texting task was completed with and without voice-to-text using a smartphone and with voice-to-text using Google Glass's HUD. Driving task performance degraded with the addition of the secondary texting task. However, voice-to-text input supported relatively better performance in both driving and texting tasks compared to using manual entry. HUD functionality further improved driving performance compared to conditions using a smartphone and often was not significantly worse than performance without the texting task. This study suggests that despite the performance costs of texting-while-driving, voice input methods improve performance over manual entry, and head-up displays may further extend those performance benefits. This study can inform designers and potential users of wearable technologies as well as policymakers tasked with regulating the use of these technologies while driving.

  2. [Effect of air-electric fields on driving and reaction patterns. Test subjects in the car driving simulator (author's transl)].

    Science.gov (United States)

    Anselm, D; Danner, M; Kirmaier, N; König, H L; Müller-Limmroth, W; Reis, A; Schauerte, W

    1977-06-10

    In the relevant frequency range of about 10 Hertz cars can be considered very largely as Faraday cages and consequently as screens against air-electric fields. This may have a negative influence on driving and reaction patterns as a result. In an extensive investigation 48 subjects in a driving simulator were exposed to definite artificially produced air-electric fields. The self-rating of the performance and concentration of the subjects, reaction times and driving errors were determined. While the reaction times remained practically constant, the driving behavior of the subjects improved.

  3. Peer Passenger Norms and Pressure: Experimental Effects on Simulated Driving Among Teenage Males.

    Science.gov (United States)

    Bingham, C Raymond; Simons-Morton, Bruce G; Pradhan, Anuj K; Li, Kaigang; Almani, Farideh; Falk, Emily B; Shope, Jean T; Buckley, Lisa; Ouimet, Marie Claude; Albert, Paul S

    2016-08-01

    Serious crashes are more likely when teenage drivers have teenage passengers. One likely source of this increased risk is social influences on driving performance. This driving simulator study experimentally tested the effects of peer influence (i.e., risk-accepting compared to risk-averse peer norms reinforced by pressure) on the driving risk behavior (i.e., risky driving behavior and inattention to hazards) of male teenagers. It was hypothesized that peer presence would result in greater driving risk behavior (i.e., increased driving risk and reduced latent hazard anticipation), and that the effect would be greater when the peer was risk-accepting. Fifty-three 16- and 17-year-old male participants holding a provisional U.S., State of Michigan driver license were randomized to either a risk-accepting or risk-averse condition. Each participant operated a driving simulator while alone and separately with a confederate peer passenger. The simulator world included scenarios designed to elicit variation in driving risk behavior with a teen passenger present in the vehicle. Significant interactions of passenger presence (passenger present vs. alone) by risk condition (risk-accepting vs. risk-averse) were observed for variables measuring: failure to stop at yellow light intersections (Incident Rate Ratio (IRR)=2.16; 95% Confidence Interval [95CI]=1.06, 4.43); higher probability of overtaking (IRR=10.17; 95CI=1.43, 73.35); shorter left turn latency (IRR=0.43; 95CI=0.31,0.60); and, failure to stop at an intersection with an occluded stop sign (IRR=7.90; 95CI=2.06,30.35). In all cases, greater risky driving by participants was more likely with a risk-accepting passenger versus a risk-averse passenger present and a risk-accepting passenger present versus driving alone. Exposure of male teenagers to a risk-accepting confederate peer passenger who applied peer influence increased simulated risky driving behavior compared with exposure to a risk-averse confederate peer

  4. A synthetic maternal-effect selfish genetic element drives population replacement in Drosophila.

    Science.gov (United States)

    Chen, Chun-Hong; Huang, Haixia; Ward, Catherine M; Su, Jessica T; Schaeffer, Lorian V; Guo, Ming; Hay, Bruce A

    2007-04-27

    One proposed strategy for controlling the transmission of insect-borne pathogens uses a drive mechanism to ensure the rapid spread of transgenes conferring disease refractoriness throughout wild populations. Here, we report the creation of maternal-effect selfish genetic elements in Drosophila that drive population replacement and are resistant to recombination-mediated dissociation of drive and disease refractoriness functions. These selfish elements use microRNA-mediated silencing of a maternally expressed gene essential for embryogenesis, which is coupled with early zygotic expression of a rescuing transgene.

  5. Mutual Coupling Effects on Pattern Diversity Antennas for MIMO Femtocells

    Directory of Open Access Journals (Sweden)

    Yue Gao

    2010-01-01

    Full Text Available Diversity antennas play an important role in wireless communications. However, mutual coupling between multiple ports of a diversity antenna has significant effects on wireless radio links and channel capacity. In this paper, dual-port pattern diversity antennas for femtocell applications are proposed to cover GSM1800, UMTS, and WLAN frequency bands. The channel capacities of the proposed antennas and two ideal dipoles with different mutual coupling levels are investigated in an indoor environment. The relation between mutual coupling and channel capacity is observed through investigations of these antennas.

  6. Effect of sonic driving on maximal aerobic performance.

    Science.gov (United States)

    Brilla, L.R.; Hatcher, Stefanie

    2000-07-01

    The study purpose was to evaluate antecedent binaural stimulation (ABS) on maximal aerobic physical performance. Twenty-two healthy, physically active subjects, 21-34 years, randomly received one of two preparations for each session: 15 min of quiet (BLANK) or percussive sonic driving at 200+ beats per minute (bpm) using a recorded compact disc (FSS, Mill Valley, CA) with headphones (ABS). Baseline HR, blood pressure (BP), and breathing frequency (f(br)) were obtained. During each condition, HR and f(br) were recorded at 3-min intervals. The graded maximal treadmill testing was administered immediately postpreparation session on separate days, with at least 48 h rest between sessions. There were significant differences in the antecedent period means between the two conditions, ABS (HR: 70.2 +/- 10.7 bpm; f(br): 18.5 +/- 3.3 br min(-1); BP: 134.5/87.9 +/- 13.6/9.2 mm Hg) and BLANK (HR: 64.6 +/- 7.9; f(br): 14.3 +/- 2.9; BP: 126.7/80.3 +/- 12.1/8.6). Differences were noted for each 3-min interval and pre- postantecedent period. The maximal graded exercise test (GXT) results showed that there was a small but significant (P 0.05). There may be a latency to ABS related to entrainment or imagery-enhanced warm-up. Am. J. Hum. Biol. 12:558-565, 2000. Copyright 2000 Wiley-Liss, Inc.

  7. Acute disinhibiting effects of alcohol as a factor in risky driving behavior

    Science.gov (United States)

    Fillmore, Mark T.; Blackburn, Jaime S.; Harrison, Emily L. R.

    2008-01-01

    Automobile crash reports show that up to 40% of fatal crashes in the United States involve alcohol and that younger drivers are over-represented. Alcohol use among young drivers is associated with impulsive and risky driving behaviors, such as speeding, which could contribute to their over-representation in alcohol-related crash statistics. Recent laboratory studies show that alcohol increases impulsive behaviors by impairing the drinker’s ability to inhibit inappropriate actions and that this effect can be exacerbated in conflict situations where the expression and inhibition of behavior are equally motivating. The present study tested the hypothesis that this response conflict might also intensify the disruptive effects of alcohol on driving performance. Fourteen subjects performed a simulated driving and a cued go/no-go task that measured their inhibitory control. Conflict was motivated in these tasks by providing equal monetary incentives for slow, careful behavior (e.g., slow driving, inhibiting impulses) and for quick, abrupt behavior (fast driving, disinhibition). Subjects were tested under two alcohol doses (0.65 g/kg and a placebo) that were administered twice: when conflict was present and when conflict was absent. Alcohol interacted with conflict to impair inhibitory control and to increase risky and impaired driving behavior on the drive task. Also, individuals whose inhibitory control was most impaired by alcohol displayed the poorest driving performance under the drug. The study demonstrates potentially serious disruptions to driving performance as a function of alcohol intoxication and response conflict, and points to inhibitory control as an important underlying mechanism. PMID:18325693

  8. Effects of large herbivores on grassland arthropod diversity.

    Science.gov (United States)

    van Klink, R; van der Plas, F; van Noordwijk, C G E Toos; WallisDeVries, M F; Olff, H

    2015-05-01

    Both arthropods and large grazing herbivores are important components and drivers of biodiversity in grassland ecosystems, but a synthesis of how arthropod diversity is affected by large herbivores has been largely missing. To fill this gap, we conducted a literature search, which yielded 141 studies on this topic of which 24 simultaneously investigated plant and arthropod diversity. Using the data from these 24 studies, we compared the responses of plant and arthropod diversity to an increase in grazing intensity. This quantitative assessment showed no overall significant effect of increasing grazing intensity on plant diversity, while arthropod diversity was generally negatively affected. To understand these negative effects, we explored the mechanisms by which large herbivores affect arthropod communities: direct effects, changes in vegetation structure, changes in plant community composition, changes in soil conditions, and cascading effects within the arthropod interaction web. We identify three main factors determining the effects of large herbivores on arthropod diversity: (i) unintentional predation and increased disturbance, (ii) decreases in total resource abundance for arthropods (biomass) and (iii) changes in plant diversity, vegetation structure and abiotic conditions. In general, heterogeneity in vegetation structure and abiotic conditions increases at intermediate grazing intensity, but declines at both low and high grazing intensity. We conclude that large herbivores can only increase arthropod diversity if they cause an increase in (a)biotic heterogeneity, and then only if this increase is large enough to compensate for the loss of total resource abundance and the increased mortality rate. This is expected to occur only at low herbivore densities or with spatio-temporal variation in herbivore densities. As we demonstrate that arthropod diversity is often more negatively affected by grazing than plant diversity, we strongly recommend considering the

  9. Effects of Cognitive Load on Driving Performance: The Cognitive Control Hypothesis.

    Science.gov (United States)

    Engström, Johan; Markkula, Gustav; Victor, Trent; Merat, Natasha

    2017-08-01

    The objective of this paper was to outline an explanatory framework for understanding effects of cognitive load on driving performance and to review the existing experimental literature in the light of this framework. Although there is general consensus that taking the eyes off the forward roadway significantly impairs most aspects of driving, the effects of primarily cognitively loading tasks on driving performance are not well understood. Based on existing models of driver attention, an explanatory framework was outlined. This framework can be summarized in terms of the cognitive control hypothesis: Cognitive load selectively impairs driving subtasks that rely on cognitive control but leaves automatic performance unaffected. An extensive literature review was conducted wherein existing results were reinterpreted based on the proposed framework. It was demonstrated that the general pattern of experimental results reported in the literature aligns well with the cognitive control hypothesis and that several apparent discrepancies between studies can be reconciled based on the proposed framework. More specifically, performance on nonpracticed or inherently variable tasks, relying on cognitive control, is consistently impaired by cognitive load, whereas the performance on automatized (well-practiced and consistently mapped) tasks is unaffected and sometimes even improved. Effects of cognitive load on driving are strongly selective and task dependent. The present results have important implications for the generalization of results obtained from experimental studies to real-world driving. The proposed framework can also serve to guide future research on the potential causal role of cognitive load in real-world crashes.

  10. Small diversity effects on ocean primary production under environmental change in a diversity-resolving ocean ecosystem model

    DEFF Research Database (Denmark)

    Prowe, Friederike; Pahlow, M.; Dutkiewicz, S.

    2013-01-01

    Marine ecosystem models used to investigate how global change affects ocean ecosystems and their functioning typically omit pelagic diversity. Diversity, however, can affect functions such as primary production and their sensitivity to environmental changes. Using a global ocean ecosystem model...... the diversity effects on ecosystem functioning captured in ocean ecosystem models....

  11. Predicting psychopharmacological drug effects on actual driving performance (SDLP) from psychometric tests measuring driving-related skills.

    Science.gov (United States)

    Verster, Joris C; Roth, Thomas

    2012-03-01

    There are various methods to examine driving ability. Comparisons between these methods and their relationship with actual on-road driving is often not determined. The objective of this study was to determine whether laboratory tests measuring driving-related skills could adequately predict on-the-road driving performance during normal traffic. Ninety-six healthy volunteers performed a standardized on-the-road driving test. Subjects were instructed to drive with a constant speed and steady lateral position within the right traffic lane. Standard deviation of lateral position (SDLP), i.e., the weaving of the car, was determined. The subjects also performed a psychometric test battery including the DSST, Sternberg memory scanning test, a tracking test, and a divided attention test. Difference scores from placebo for parameters of the psychometric tests and SDLP were computed and correlated with each other. A stepwise linear regression analysis determined the predictive validity of the laboratory test battery to SDLP. Stepwise regression analyses revealed that the combination of five parameters, hard tracking, tracking and reaction time of the divided attention test, and reaction time and percentage of errors of the Sternberg memory scanning test, together had a predictive validity of 33.4%. The psychometric tests in this test battery showed insufficient predictive validity to replace the on-the-road driving test during normal traffic.

  12. Tree diversity and species identity effects on soil fungi, protists and animals are context dependent.

    Science.gov (United States)

    Tedersoo, Leho; Bahram, Mohammad; Cajthaml, Tomáš; Põlme, Sergei; Hiiesalu, Indrek; Anslan, Sten; Harend, Helery; Buegger, Franz; Pritsch, Karin; Koricheva, Julia; Abarenkov, Kessy

    2016-02-01

    Plant species richness and the presence of certain influential species (sampling effect) drive the stability and functionality of ecosystems as well as primary production and biomass of consumers. However, little is known about these floristic effects on richness and community composition of soil biota in forest habitats owing to methodological constraints. We developed a DNA metabarcoding approach to identify the major eukaryote groups directly from soil with roughly species-level resolution. Using this method, we examined the effects of tree diversity and individual tree species on soil microbial biomass and taxonomic richness of soil biota in two experimental study systems in Finland and Estonia and accounted for edaphic variables and spatial autocorrelation. Our analyses revealed that the effects of tree diversity and individual species on soil biota are largely context dependent. Multiple regression and structural equation modelling suggested that biomass, soil pH, nutrients and tree species directly affect richness of different taxonomic groups. The community composition of most soil organisms was strongly correlated due to similar response to environmental predictors rather than causal relationships. On a local scale, soil resources and tree species have stronger effect on diversity of soil biota than tree species richness per se.

  13. The effect of organic farming systems on species diversity

    Science.gov (United States)

    Leksono, Amin Setyo

    2017-11-01

    Organic farming systems have been well known to support the diversity of a wide range of taxa, including microorganisms, arable flora, invertebrates, birds, and mammals, which benefit from organic management leading to increases in abundance and/or species richness. The objective of this paper is to review the effect of organic farming on species diversity reported in several articles and compare this with the current study in Gondanglegi, Malang. A review of several studies showed that organic farming systems have been reported to increase species diversity, including that of mammals, birds, arthropods, vascular plants and arbuscular mycorrhizal fungi. The researchers about arthropod groups consisted of carabid beetles, butterflies, wasps, predators, and bees. Agricultural landscape, habitat type, farming system, landscape composition and connectivity all contribute to explaining species biodiversity and richness. Moreover, based on current and relevant studies, the results showed that the application of refugia blocks has increased arthropod diversity and composition.

  14. Exploring workplace diversity and organisational effectiveness: A South African exploratory case study

    Directory of Open Access Journals (Sweden)

    J. Veli Mazibuko

    2017-11-01

    Full Text Available Orientation: Transformation and managing diversity are organisational imperatives, especially in South Africa. Thus, it is important for international companies with major operations in South Africa (SA to embrace the benefits of managing a divergent workforce and translate this for organisational benefits. Research purpose: The article explores the perceptions of management and staff on diversity and its value to the organisation, by empirically evaluating the relationship with organisational effectiveness and performance through the development and testing of five hypotheses. Motivation for the study: Legislation has made it mandatory for transformation of the South African workplace and ensuring that diversity is embraced. However, not all companies have fully understood the benefits of recruiting and managing diverse teams for the benefit of the organisation. Research approach, design and method: Both quantitative and qualitative approaches were used, whereby a survey was conducted among 227 employees using the Towers Watson Employment Employee Insight Survey (EIS. Inferential statistical techniques were used to test relationships among related variables postulated through five hypotheses. Main findings: It was ascertained that understanding and managing diversity has played a pivotal role in the (research organisation’s performance and effectiveness over the past 5 years. More specifically, diversity management created room for appreciation, innovation and creativity that gave the organisations an edge to tackle diverse markets. Practical/managerial applications: South Africa has a diverse population, and when individuals join an organisation, they bring a unique set of characteristics referred to as personalities, which, through the socialisation process, get assimilated into teams’ norms and values, and the culture of the organisation. Managing diversity in the workplace is part of employee retention and attraction, with the intention

  15. The effects of positive emotion priming on self-reported reckless driving.

    Science.gov (United States)

    Taubman-Ben-Ari, Orit

    2012-03-01

    Five studies examined the effects of positive emotion priming on the willingness to drive recklessly. In all five, young drivers were exposed to one of the following primes of positive affect: a positive mood story; happy memories; an exciting film; a relaxing film; or thoughts on the meaning in life. Following the prime, the participants were asked to report on their willingness to drive recklessly. The responses were compared to those of groups exposed either to neutral affect, another kind of positive affect, or negative affect priming. In two of the studies, participants were also asked to report on their driving styles (risky, anxious, angry, or careful) as a second dependent variable. Positive affect, especially in the form of arousal, was found to be related to higher willingness to drive recklessly. Although men tended to report higher intentions to drive recklessly, men and women did not react differently to the emotional induction. Most interestingly, positive emotions of a relaxing nature, as well as thinking about the meaning in life, lowered the willingness to engage in risky driving. The discussion emphasizes the importance of looking for new ways to use positive emotions effectively in road safety interventions, and considers the practical implications of the studies. Copyright © 2011 Elsevier Ltd. All rights reserved.

  16. What drives the comparability effect of mandatory IFRS adoption?

    OpenAIRE

    Stefano Cascino; Joachim Gassen

    2015-01-01

    We investigate the effects of mandatory IFRS adoption on the comparability of financial accounting information. Using two comparability proxies based on De Franco et al. [2011] and a comparability proxy based on the degree of information transfer, our results suggest that the overall comparability effect of mandatory IFRS adoption is marginal. We hypothesize that firm-level heterogeneity in IFRS compliance explains the limited comparability effect. To test this conjecture, we first hand-colle...

  17. Revision of the Late Jurassic crocodyliform Alligatorellus, and evidence for allopatric speciation driving high diversity in western European atoposaurids.

    Science.gov (United States)

    Tennant, Jonathan P; Mannion, Philip D

    2014-01-01

    Atoposaurid crocodyliforms represent an important faunal component of Late Jurassic to Early Cretaceous Laurasian semi-aquatic to terrestrial ecosystems, with numerous spatiotemporally contemporaneous atoposaurids known from western Europe. In particular, the Late Jurassic of France and Germany records evidence for high diversity and possible sympatric atoposaurid species belonging to Alligatorellus, Alligatorium and Atoposaurus. However, atoposaurid taxonomy has received little attention, and many species are in need of revision. As such, this potentially high European diversity within a narrow spatiotemporal range might be a taxonomic artefact. Here we provide a taxonomic and anatomical revision of the Late Jurassic atoposaurid Alligatorellus. Initially described as A. beaumonti from the Kimmeridgian of Cerin, eastern France, additional material from the Tithonian of Solnhofen, south-eastern Germany, was subsequently referred to this species, with the two occurrences differentiated as A. beaumonti beaumonti and A. beaumonti bavaricus, respectively. We provide a revised diagnosis for the genus Alligatorellus, and note a number of anatomical differences between the French and German specimens, including osteoderm morphology and the configuration and pattern of sculpting of cranial elements. Consequently, we restrict the name Alligatorellus beaumonti to include only the French remains, and raise the rank of the German material to a distinct species: Alligatorellus bavaricus. A new diagnosis is provided for both species, and we suggest that a recently referred specimen from a coeval German locality cannot be conclusively referred to Alligatorellus. Although it has previously been suggested that Alligatorellus, Alligatorium and Atoposaurus might represent a single growth series of one species, we find no conclusive evidence to support this proposal, and provide a number of morphological differences to distinguish these three taxa that appear to be independent of

  18. Effects of Lane Width, Lane Position and Edge Shoulder Width on Driving Behavior in Underground Urban Expressways: A Driving Simulator Study

    Directory of Open Access Journals (Sweden)

    Shuo Liu

    2016-10-01

    Full Text Available This study tested the effects of lane width, lane position and edge shoulder width on driving behavior for a three-lane underground urban expressway. A driving simulator was used with 24 volunteer test subjects. Five lane widths (2.85, 3.00, 3.25, 3.50, and 3.75 m and three shoulder widths (0.50, 0.75, and 1.00 m were studied. Driving speed, lane deviation and subjective perception of driving behavior were collected as performance measures. The results show that lane and shoulder width have significant effects on driving speed. Average driving speed increases from 60.01 km/h in the narrowest lane to 88.05 km/h in the widest lane. While both narrower lanes and shoulders result in reduced speed and lateral lane deviation, the effect of lane width is greater than that of shoulder width. When the lane and shoulder are narrow, drivers in the left or right lane tend to shy away from the tunnel wall, even encroaching into the neighboring middle lane. As the lane or shoulder gets wider, drivers tend to stay in the middle of the lane. An interesting finding is that although few participants acknowledged that lane position had any great bearing on their driving behaviors, the observed driving speed is statistically higher in the left lane than in the other two lanes when the lane width is narrow (in 2.85, 3 and 3.25 m lanes. These findings provided support for amending the current design specifications of urban underground roads, such as the relationship between design speed and lane width, speed limit, and combination form of lanes.

  19. What drives employment growth of Canadian Businesses? A Fresh Look at Indicators of Agglomeration Economies when Competition and Diversity Matter

    DEFF Research Database (Denmark)

    Wang, Cong; Steiner, Bodo

    2014-01-01

    This study investigates indicators of external scale economies in Canada for the period 2004-11. Accounting for firm-level external scale forces, we explore the extent to which external scale economies impact employment growth. Our analysis focuses on three factors: the impact of external scale...... economies accounting for Marshallian specialization and Jacobs diversity, competition by industry, and related and unrelated firm varieties in terms of employment and sales. Results accounting for non-linearity between employment growth and agglomeration suggest that in the short run, during the period 2004...

  20. A meta-analysis of the effects of texting on driving.

    Science.gov (United States)

    Caird, Jeff K; Johnston, Kate A; Willness, Chelsea R; Asbridge, Mark; Steel, Piers

    2014-10-01

    Text messaging while driving is considered dangerous and known to produce injuries and fatalities. However, the effects of text messaging on driving performance have not been synthesized or summarily estimated. All available experimental studies that measured the effects of text messaging on driving were identified through database searches using variants of "driving" and "texting" without restriction on year of publication through March 2014. Of the 1476 abstracts reviewed, 82 met general inclusion criteria. Of these, 28 studies were found to sufficiently compare reading or typing text messages while driving with a control or baseline condition. Independent variables (text-messaging tasks) were coded as typing, reading, or a combination of both. Dependent variables included eye movements, stimulus detection, reaction time, collisions, lane positioning, speed and headway. Statistics were extracted from studies to compute effect sizes (rc). A total sample of 977 participants from 28 experimental studies yielded 234 effect size estimates of the relationships among independent and dependent variables. Typing and reading text messages while driving adversely affected eye movements, stimulus detection, reaction time, collisions, lane positioning, speed and headway. Typing text messages alone produced similar decrements as typing and reading, whereas reading alone had smaller decrements over fewer dependent variables. Typing and reading text messages affects drivers' capability to adequately direct attention to the roadway, respond to important traffic events, control a vehicle within a lane and maintain speed and headway. This meta-analysis provides convergent evidence that texting compromises the safety of the driver, passengers and other road users. Combined efforts, including legislation, enforcement, blocking technologies, parent modeling, social media, social norms and education, will be required to prevent continued deaths and injuries from texting and driving

  1. Effect of different alcohol levels on take-over performance in conditionally automated driving.

    Science.gov (United States)

    Wiedemann, Katharina; Naujoks, Frederik; Wörle, Johanna; Kenntner-Mabiala, Ramona; Kaussner, Yvonne; Neukum, Alexandra

    2018-06-01

    Automated driving systems are getting pushed into the consumer market, with varying degrees of automation. Most often the driver's task will consist of being available as a fall-back level when the automation reaches its limits. These so-called take-over situations have attracted a great body of research, focusing on various human factors aspects (e.g., sleepiness) that could undermine the safety of control transitions between automated and manual driving. However, a major source of accidents in manual driving, alcohol consumption, has been a non-issue so far, although a false understanding of the driver's responsibility (i.e., being available as a fallback level) might promote driving under its influence. In this experiment, N = 36 drivers were exposed to different levels of blood alcohol concentrations (BACs: placebo vs. 0.05% vs. 0.08%) in a high fidelity driving simulator, and the effect on take-over time and quality was assessed. The results point out that a 0.08% BAC increases the time needed to re-engage in the driving task and impairs several aspects of longitudinal and lateral vehicle control, whereas 0.05% BAC did only go along with descriptive impairments in fewer parameters. Copyright © 2018 The Authors. Published by Elsevier Ltd.. All rights reserved.

  2. Do driving restriction policies effectively motivate commuters to use public transportation?

    International Nuclear Information System (INIS)

    Liu, Yunxia; Hong, Zaisheng; Liu, Yong

    2016-01-01

    Driving restriction policies have been implemented in some large Chinese cities to cope with severe urban smog pollution. We explored the roles of policy acceptance and other factors in commuters' transport mode decisions, based on the Theory of Planned Behavior. A questionnaire survey was conducted in Tianjin, China. A structural equation model was developed to test eight hypotheses, two of which were rejected. The results indicate that a driving restriction policy alone cannot effectively motivate commuters to use public transport if the policymakers fail to improve public transport, enhance commuters' awareness of consequences, increase commuters' perceived behavior control, and encourage car owners to change driving behavior. Comparisons between car owners and non-owners indicated that car owners view driving restriction policy and public transport more negatively. These negative views could be a barrier for the promotion of public transport among car owners. In addition, attitude toward public transport was found to have positive correlation with commuting time. - Highlights: • Attitude towards public transport has an impact on policy acceptance. • Driving habit indirectly affects policy acceptance and perceived behavior control. • Driving restriction policy and public transport are not popular among car owners. • Attitude towards public transport correlates positively with commuting time.

  3. Effects of fog, driver experience and gender on driving behavior on S-curved road segments.

    Science.gov (United States)

    Li, Xiaomeng; Yan, Xuedong; Wong, S C

    2015-04-01

    Driving on curved roads has been recognized as a significant safety issue for many years. However, driver behavior and the interactions among variables that affect driver performance on curves is complicated and not well understood. Previous studies have investigated various factors that influence driver performance on right- or left-turn curves, but have paid little attention to the effects of foggy weather, driver experience and gender on driver performance on complex curves. A driving simulator experiment was conducted in this study to evaluate the relationships between driving behavior on a continuous S-curve and foggy weather, driver experience and gender. The process of negotiating a curve was divided into three stages consisting of a straight segment, the transition from the straight segment to the S-curve and the S-curve. The experimental results indicated that drivers tended to drive more cautiously in heavy fog, but the driving risk was still increased, especially in the transition stage from the straight segment to the S-curve. The non-professional (NP) drivers were less sensitive to the impending change in the road geometry, and less skilled in both longitudinal and lateral vehicle control than the professional drivers. The NP female drivers in particular were found to be the most vulnerable group in S-curve driving. Copyright © 2015 Elsevier Ltd. All rights reserved.

  4. Acute effects of alcohol on inhibitory control and simulated driving in DUI offenders.

    Science.gov (United States)

    Van Dyke, Nicholas; Fillmore, Mark T

    2014-06-01

    The public health costs associated with alcohol-related traffic accidents have prompted considerable research aimed at identifying characteristics of individuals who drive under the influence (DUI) in order to improve treatment and prevention strategies. Survey studies consistently show that DUI offenders self-report higher levels of impulsivity compared to their nonoffending counterparts. However, little is known about how individuals with a DUI history respond under alcohol. Inhibitory control is a behavioral component of impulsivity thought to underlie risky drinking and driving behaviors. The present study examined the degree to which DUI drivers display deficits of inhibitory control in response to alcohol and the degree to which alcohol impaired their simulated driving performance. It was hypothesized that DUI offenders would display an increased sensitivity to the acute impairing effects of alcohol on simulated driving performance. Young adult drivers with a history of DUI and a demographically-comparable group of drivers with no history of DUI (controls) were tested following a 0.65 g/kg dose of alcohol and a placebo. Inhibitory control was measured by using a cued go/no-go task. Drivers then completed a driving simulation task that yielded multiple indicators of driving performance, such as within-lane deviation, steering rate, centerline crossings and road edge excursions, and drive speed. Results showed that although DUI offenders self-reported greater levels of impulsivity than did controls, no group differences were observed in the degree to which alcohol impaired inhibitory control and driving performance. The findings point to the need to identify other aspects of behavioral dysfunction underlying the self-reported impulsivity among DUI offenders, and to better understand the specific driving situations that might pose greater risk to DUI offenders. The systematic study of candidate cognitive deficits in DUI offenders will provide important

  5. Speed-calming measures and their Effect on driving speed

    DEFF Research Database (Denmark)

    Agerholm, Niels; Knudsen, Daniel; Variyeswaran, Kajan

    2017-01-01

    Highlights •Speed humps and chicanes are widespread speed-calming measures. •Humps and chicanes have virtually the same reducing effect on mean speed. •Chicanes reduce speed variation less than humps and might therefore be a less safe measure....

  6. Young drivers and effects from graduated driving license

    DEFF Research Database (Denmark)

    Tønning, Charlotte; Agerholm, Niels

    2016-01-01

    be expected from advanced driver training, and if possible to identify, which measures there have the best effect on traffic safety. Method or methodological issues The method is literature studies. All Scandinavian-written reports and articles are screened. Likewise, are ScienceDirect, Google Scholar...

  7. Effects of dexamphetamine with and without alcohol on simulated driving

    NARCIS (Netherlands)

    Simons, M.; Martens, M.H.; Ramaekers, J.; Krul, A.; Klöpping-Ketelaars, I.; Skopp, G.

    2012-01-01

    Rationale In party circuits dexamphetamine is frequently used in combination with alcohol. It is hypothesized that co-administration of dexamphetamine to alcohol might reduce the sedative effects of alcohol, but may potentiate risk-taking behaviour. Objectives The study was aimed at assessing the

  8. Effects of dexamphetamine with and without alcohol on simulated driving

    NARCIS (Netherlands)

    Simons, R.; Martens, Marieke Hendrikje; Ramaekers, J.; Krul, A.; Klöpping-Ketelaars, I.; Skopp, G.

    2012-01-01

    Rationale: In party circuits dexamphetamine is frequently used in combination with alcohol. It is hypothesized that co-administration of dexamphetamine to alcohol might reduce the sedative effects of alcohol, but may potentiate risk-taking behaviour. Objectives: The study was aimed at assessing the

  9. Altered interactions between unicellular and multicellular genes drive hallmarks of transformation in a diverse range of solid tumors.

    Science.gov (United States)

    Trigos, Anna S; Pearson, Richard B; Papenfuss, Anthony T; Goode, David L

    2017-06-13

    Tumors of distinct tissues of origin and genetic makeup display common hallmark cellular phenotypes, including sustained proliferation, suppression of cell death, and altered metabolism. These phenotypic commonalities have been proposed to stem from disruption of conserved regulatory mechanisms evolved during the transition to multicellularity to control fundamental cellular processes such as growth and replication. Dating the evolutionary emergence of human genes through phylostratigraphy uncovered close association between gene age and expression level in RNA sequencing data from The Cancer Genome Atlas for seven solid cancers. Genes conserved with unicellular organisms were strongly up-regulated, whereas genes of metazoan origin were primarily inactivated. These patterns were most consistent for processes known to be important in cancer, implicating both selection and active regulation during malignant transformation. The coordinated expression of strongly interacting multicellularity and unicellularity processes was lost in tumors. This separation of unicellular and multicellular functions appeared to be mediated by 12 highly connected genes, marking them as important general drivers of tumorigenesis. Our findings suggest common principles closely tied to the evolutionary history of genes underlie convergent changes at the cellular process level across a range of solid cancers. We propose altered activity of genes at the interfaces between multicellular and unicellular regions of human gene regulatory networks activate primitive transcriptional programs, driving common hallmark features of cancer. Manipulation of cross-talk between biological processes of different evolutionary origins may thus present powerful and broadly applicable treatment strategies for cancer.

  10. Effect of ethylic alcohol on attentive functions involved in driving abilities.

    Science.gov (United States)

    Bivona, Umberto; Garbarino, Sergio; Rigon, Jessica; Buzzi, Maria Gabriella; Onder, Graziano; Matteis, Maria; Catani, Sheila; Giustini, Marco; Mancardi, Giovanni Luigi; Formisano, Rita

    2015-01-01

    The burden of injuries due to drunk drivers has been estimated only indirectly. Indeed, alcohol is considered one of the most important contributing cause of car crash injuries and its effect on cognitive functions needs to be better elucidated. Aims of the study were i) to examine the effect of alcohol on attentive abilities involved while driving, and ii) to investigate whether Italian law limits for safe driving are sufficiently accurate to prevent risky behaviours and car crash risk while driving. We conducted a cross-over study at IRCCS Fondazione Santa Lucia Rehabilitation Hospital in Rome. Thirty-two healthy subjects were enrolled in this experiment. Participants were submitted to an attentive test battery assessing attention before taking Ethylic Alcohol (EA-) and after taking EA (EA+). In the EA+ condition subjects drank enough wine until the blood alcohol concentration, measured by means of Breath Analyzer, was equal to or higher than 0.5 g/l. Data analysis revealed that after alcohol assumption, tonic and phasic alertness, selective, divided attention and vigilance were significantly impaired when BAC level was at least 0.5 g/l. These data reveal that alcohol has a negative effect on attentive functions which are primarily involved in driving skills and that Italian law limits are adequate to prevent risky driving behaviour.

  11. Effects of valerian on subjective sedation, field sobriety testing and driving simulator performance.

    Science.gov (United States)

    Thomas, Kelan; Canedo, Joanne; Perry, Paul J; Doroudgar, Shadi; Lopes, Ingrid; Chuang, Hannah Mae; Bohnert, Kimberly

    2016-07-01

    The availability of herbal medicines over-the-counter (OTC) has increased the use of natural products for self-treatment. Valerian has been used to effectively treat generalized anxiety disorder and insomnia. Studies suggest that valerenic acid may increase gamma-aminobutyric acid (GABA) modulation in the brain. Benzodiazepines have a similar mechanism of action and have been linked to an increased risk of hospitalizations due to traffic accidents. Despite the risk of somnolence, the safety of driving while under the influence of valerian remains unknown. The purpose of the study was to determine the effects of a one-time valerian 1600mg dose on subjective sedation effects, standardized field sobriety testing (SFST) and driving simulator performance parameters. The study design was a randomized, placebo-controlled, double-blind, cross-over trial. For each session, participants received either a dose of valerian or placebo. The outcome measures included a simple visual reaction test (SVRT), subjective sleepiness scales, SFST performance scores, and driving simulator performance parameters. There were no significant differences in the SVRT or sleepiness scales between placebo and valerian exposures, but the study may have been underpowered. SFST total and individual test failure rates were not significantly different between the two exposures. The driving simulator performance parameters were equivalent between the two exposure conditions. A one-time valerian 1600mg dose, often used to treat insomnia, does not appear to impair driving simulator performance after acute ingestion. Copyright © 2016 Elsevier Ltd. All rights reserved.

  12. A familiar font drives early emotional effects in word recognition.

    Science.gov (United States)

    Kuchinke, Lars; Krause, Beatrix; Fritsch, Nathalie; Briesemeister, Benny B

    2014-10-01

    The emotional connotation of a word is known to shift the process of word recognition. Using the electroencephalographic event-related potentials (ERPs) approach it has been documented that early attentional processing of high-arousing negative words is shifted at a stage of processing where a presented word cannot have been fully identified. Contextual learning has been discussed to contribute to these effects. The present study shows that a manipulation of the familiarity with a word's shape interferes with these earliest emotional ERP effects. Presenting high-arousing negative and neutral words in a familiar or an unfamiliar font results in very early emotion differences only in case of familiar shapes, whereas later processing stages reveal similar emotional effects in both font conditions. Because these early emotion-related differences predict later behavioral differences, it is suggested that contextual learning of emotional valence comprises more visual features than previously expected to guide early visual-sensory processing. Copyright © 2014 Elsevier Inc. All rights reserved.

  13. Cultural Diversity in Military Teams: Which Factors Influence Effectiveness?

    Science.gov (United States)

    2008-12-01

    TNO-DV2008A513 Opdrachtnummer Datum december 2008 Auteur (s) dr. I.M. Wetzer dr. D.A. van Hemert Rubricering rapport Ongerubriceerd TM0...been reported. Based on Allport’s (1954) intergroup contact theory , positive effects of intercultural contact may occur under certain conditions...diversity on perceived team effectiveness, but only at the 11-30% level. In contrast, social identity theory would lead one to expect negative effects of

  14. Effect of single-dose Ginkgo biloba and Panax ginseng on driving performance.

    Science.gov (United States)

    LaSala, Gregory S; McKeever, Rita G; Patel, Urvi; Okaneku, Jolene; Vearrier, David; Greenberg, Michael I

    2015-02-01

    Panax ginseng and Gingko biloba are commonly used herbal supplements in the United States that have been reported to increase alertness and cognitive function. The objective of this study was to investigate the effects of these specific herbals on driving performance. 30 volunteers were tested using the STISIM3® Driving Simulator (Systems Technology Inc., Hawthorne, CA, USA) in this double-blind, placebo-controlled study. The subjects were randomized into 3 groups of 10 subjects per group. After 10-min of simulated driving, subjects received either ginseng (1200 mg), Gingko (240 mg), or placebo administered orally. The test herbals and placebo were randomized and administered by a research assistant outside of the study to maintain blinding. One hour following administration of the herbals or placebo, the subjects completed an additional 10-min of simulated driving. Standard driving parameters were studied including reaction time, standard deviation of lateral positioning, and divided attention. Data collected for the divided attention parameter included time to response and number of correct responses. The data was analyzed with repeated-measures analysis of variance (ANOVA) and Kruskal-Wallis test using SPSS 22 (IBM, Armonk, NY, USA). There was no difference in reaction time or standard deviation of lateral positioning for both the ginseng and Ginkgo arms. For the divided attention parameter, the response time in the Ginkgo arm decreased from 2.9 to 2.5 s. The ginseng arm also decreased from 3.2 to 2.4 s. None of these values were statistically significant when between group differences were analyzed. The data suggests there was no statistically significant difference between ginseng, Ginkgo or placebo on driving performance. We postulate this is due to the relatively small numbers in our study. Further study with a larger sample size may be needed in order to elucidate more fully the effects of Ginkgo and ginseng on driving ability.

  15. Effects of alprazolam on driving ability, memory functioning and psychomotor performance: a randomized, placebo-controlled study.

    Science.gov (United States)

    Verster, Joris C; Volkerts, Edmund R; Verbaten, Marinus N

    2002-08-01

    Alprazolam is prescribed for the treatment of anxiety and panic disorder. Most users are presumably involved in daily activities such as driving. However, the effects of alprazolam on driving ability have never been investigated. This study was conducted to determine the effects of alprazolam (1 mg) on driving ability, memory and psychomotor performance. Twenty healthy volunteers participated in a randomized, double-blind, placebo-controlled crossover study. One hour after oral administration, subjects performed a standardized driving test on a primary highway during normal traffic. They were instructed to drive with a constant speed (90 km/h) while maintaining a steady lateral position within the right traffic lane. Primary performance measures were the Standard Deviation of Lateral Position (SDLP) and the Standard Deviation of Speed (SDS). After the driving test, subjective driving quality, mental effort, and mental activation during driving were assessed. A laboratory test battery was performed 2.5 h after treatment administration, comprising the Sternberg Memory Scanning Test, a Continuous Tracking Test, and a Divided Attention Test. Relative to placebo, alprazolam caused serious driving impairment, as expressed by a significantly increased SDLP (F(1,19) = 97.3, p driving quality (F(1,19) = 16.4, p driving (F(1,19) = 26.4, p drive an automobile or operate potentially dangerous machinery.

  16. Diverse Friendship Networks and Heterogeneous Peer Effects on Adolescent Misbehaviors

    Science.gov (United States)

    Xu, Yilan; Fan, Linlin

    2018-01-01

    This study estimates peer effects in diverse friendship networks by friend types. Evidence from friendship networks for 57,351 U.S. high school adolescents demonstrates that adolescents are more likely to make friends with someone of the same immigrant status or ethnicity ('similar friends') than those with different backgrounds ('dissimilar…

  17. Comparing headphone and speaker effects on simulated driving.

    Science.gov (United States)

    Nelson, T M; Nilsson, T H

    1990-12-01

    Twelve persons drove for three hours in an automobile simulator while listening to music at sound level 63dB over stereo headphones during one session and from a dashboard speaker during another session. They were required to steer a mountain highway, maintain a certain indicated speed, shift gears, and respond to occasional hazards. Steering and speed control were dependent on visual cues. The need to shift and the hazards were indicated by sound and vibration effects. With the headphones, the driver's average reaction time for the most complex task presented--shifting gears--was about one-third second longer than with the speaker. The use of headphones did not delay the development of subjective fatigue.

  18. The Immoral Assumption Effect: Moralization Drives Negative Trait Attributions.

    Science.gov (United States)

    Meindl, Peter; Johnson, Kate M; Graham, Jesse

    2016-04-01

    Jumping to negative conclusions about other people's traits is judged as morally bad by many people. Despite this, across six experiments (total N = 2,151), we find that multiple types of moral evaluations--even evaluations related to open-mindedness, tolerance, and compassion--play a causal role in these potentially pernicious trait assumptions. Our results also indicate that moralization affects negative-but not positive-trait assumptions, and that the effect of morality on negative assumptions cannot be explained merely by people's general (nonmoral) preferences or other factors that distinguish moral and nonmoral traits, such as controllability or desirability. Together, these results suggest that one of the more destructive human tendencies--making negative assumptions about others--can be caused by the better angels of our nature. © 2016 by the Society for Personality and Social Psychology, Inc.

  19. Literature review on risky driving videos on YouTube: Unknown effects and areas for concern?

    Science.gov (United States)

    Vingilis, Evelyn; Yıldırım-Yenier, Zümrüt; Vingilis-Jaremko, Larissa; Wickens, Christine; Seeley, Jane; Fleiter, Judy; Grushka, Daniel H

    2017-08-18

    Entry of terms reflective of extreme risky driving behaviors into the YouTube website yields millions of videos. The majority of the top 20 highly subscribed automotive YouTube websites are focused on high-performance vehicles, high speed, and often risky driving. Moreover, young men are the heaviest users of online video sharing sites, overall streaming more videos, and watching them longer than any other group. The purpose of this article is to review the literature on YouTube videos and risky driving. A systematic search was performed using the following specialized database sources-Scopus, PubMed, Web of Science, ERIC, and Google Scholar-for the years 2005-2015 for articles in the English language. Search words included "YouTube AND driving," "YouTube AND speeding," "YouTube AND racing." No published research was found on the content of risky driving videos or on the effects of these videos on viewers. This literature review presents the current state of our published knowledge on the topic, which includes a review of the effects of mass media on risky driving cognitions; attitudes and behavior; similarities and differences between mass and social media; information on the YouTube platform; psychological theories that could support YouTube's potential effects on driving behavior; and 2 examples of risky driving behaviors ("sidewalk skiing" and "ghost riding the whip") suggestive of varying levels of modeling behavior in subsequent YouTube videos. Every month about 1 billion individuals are reported to view YouTube videos (ebizMBA Guide 2015 ) and young men are the heaviest users, overall streaming more YouTube videos and watching them longer than women and other age groups (Nielsen 2011 ). This group is also the most dangerous group in traffic, engaging in more per capita violations and experiencing more per capita injuries and fatalities (e.g., Parker et al. 1995 ; Reason et al. 1990 ; Transport Canada 2015 ; World Health Organization 2015 ). YouTube also

  20. Effects of land use on taxonomic and functional diversity

    DEFF Research Database (Denmark)

    Hevia, Violeta; Carmona, Carlos P.; Azcárate, Francisco M.

    2016-01-01

    Land-use change is the major driver of biodiversity loss. However, taxonomic diversity (TD) and functional diversity (FD) might respond differently to land-use change, and this response might also vary depending on the biotic group being analysed. In this study, we compare the TD and FD of four......: the sampling unit scale and the site scale. Land-use intensity effects on TD and FD were quite different and highly varied among the four biotic groups, with no single clear pattern emerging that could be considered general for all organisms. Additive partitioning of species diversity revealed clear...... contrasting patterns between TD and FD in the percentage of variability observed at each spatial scale. While most variability in TD was found at the larger scales, irregardless of organism group and land-use type, most variability in FD was found at the smallest scale, indicating that species turnover among...

  1. Structural diversity effect on hashtag adoption in Twitter

    Science.gov (United States)

    Zhang, Aihua; Zheng, Mingxing; Pang, Bowen

    2018-03-01

    With online social network developing rapidly these years, user' behavior in online social network has attracted a lot of attentions to it. In this paper, we study Twitter user's behavior of hashtag adoption from the perspective of social contagion and focus on "structure diversity" effect on individual's behavior in Twitter. We achieve data through Twitter's API by crawling and build a users' network to carry on empirical research. The Girvan-Newman (G-N) algorithm is used to analyze the structural diversity of user's ego network, and Logistic regression model is adopted to examine the hypothesis. The findings of our empirical study indicate that user' behavior in online social network is indeed influenced by his friends and his decision is significantly affected by the number of groups that these friends belong to, which we call structural diversity.

  2. Alien reef-building polychaete drives long-term changes in invertebrate biomass and diversity in a small, urban estuary

    Science.gov (United States)

    McQuaid, K. A.; Griffiths, C. L.

    2014-02-01

    Two of the greatest threats to native biodiversity are the construction of artificial structures in natural environments and the introduction of invasive species. As the development and urbanisation of estuaries continues at an increasing rate worldwide, these environments are being simultaneously affected by these threats. This study quantifies the spread of an invasive reef-building polychaete, Ficopomatus enigmaticus, in a small, highly manipulated urban estuary in South Africa and investigates its role as an ecosystem engineer. Anthropogenic changes to the Zandvlei Estuary, including construction of a rubble weir and canalisation near the estuary mouth, construction of an extensive marina development and hardening of the banks with concrete, have facilitated the expansion of F. enigmaticus. The standing stock of F. enigmaticus increased from 13.69 t, as measured in 1986, to 50.03 t in 2012, due both to increase in the total area colonised and standing stock per m2. Since F. enigmaticus reefs support a greater biomass of infauna than adjacent sandy areas, total invertebrate biomass in the estuary is estimated to have increased from less than 0.30 t in 1942, to over 56.80 t in 2012, due mainly to hardening of banks in parts of the main estuary with concrete and construction of a marina system. A positive correlation between reef mass and infaunal biomass, density and diversity was also found.

  3. Different flour microbial communities drive to sourdoughs characterized by diverse bacterial strains and free amino acid profiles

    Directory of Open Access Journals (Sweden)

    GIUSEPPE CELANO

    2016-11-01

    Full Text Available This work aimed to investigate whether different microbial assemblies in flour may influence the microbiological and biochemical characteristics of traditional sourdough. To reach this purpose, members of lactic acid bacteria, enterobacteria, and yeasts were isolated from durum wheat flour. Secondly, the isolated microorganisms (Pediococcus pentosaceus, Saccharomyces cerevisiae, Pantoea agglomerans, and Escherichia hermanni were inoculated in doughs prepared with irradiated flour (gamma rays at 10 kGy, so that eight different microbial assemblies were obtained. Two non-inoculated controls were prepared, one of which (C-IF using irradiated flour and the other (C using non-irradiated flour.As shown by plate counts, irradiation of flour caused total inactivation of yeasts and a decrease of all the other microbial populations. However acidification occurred also in the dough C-IF, due to metabolic activity of P. pentosaceus that had survived irradiation. After six fermentations, P. pentosaceus was the dominant lactic acid bacterium species in all the sourdoughs produced with irradiated flour (IF. Yet, IF-based sourdoughs broadly differed from each other in terms of strains of P. pentosaceus, probably due to the different microorganisms initially inoculated. Quantitative and qualitative differences of free amino acids concentration were found among the sourdoughs, possibly because of different microbial communities. In addition, as shown by culture-independent analysis (16S metagenetics, irradiation of flour lowered and modified microbial diversity of sourdough ecosystem.

  4. Good distractions: Testing the effects of listening to an audiobook on driving performance in simple and complex road environments.

    Science.gov (United States)

    Nowosielski, Robert J; Trick, Lana M; Toxopeus, Ryan

    2018-02-01

    Distracted driving (driving while performing a secondary task) causes many collisions. Most research on distracted driving has focused on operating a cell-phone, but distracted driving can include eating while driving, conversing with passengers or listening to music or audiobooks. Although the research has focused on the deleterious effects of distraction, there may be situations where distraction improves driving performance. Fatigue and boredom are also associated with collision risk and it is possible that secondary tasks can help alleviate the effects of fatigue and boredom. Furthermore, it has been found that individuals with high levels of executive functioning as measured by the OSPAN (Operation Span) task show better driving while multitasking. In this study, licensed drivers were tested in a driving simulator (a car body surrounded by screens) that simulated simple or complex roads. Road complexity was manipulated by increasing traffic, scenery, and the number of curves in the drive. Participants either drove, or drove while listening to an audiobook. Driving performance was measured in terms of braking response time to hazards (HRT): the time required to brake in response to pedestrians or vehicles that suddenly emerged from the periphery into the path of the vehicle, speed, standard deviation of speed, standard deviation of lateral position (SDLP). Overall, braking times to hazards were higher on the complex drive than the simple one, though the effects of secondary tasks such as audiobooks were especially deleterious on the complex drive. In contrast, on the simple drive, driving while listening to an audiobook lead to faster HRT. We found evidence that individuals with high OSPAN scores had faster HRTs when listening to an audiobook. These results suggest that there are environmental and individual factors behind difference in the allocation of attention while listening to audiobooks while driving. Copyright © 2017 Elsevier Ltd. All rights reserved.

  5. A comparison of the effect of mobile phone use and alcohol consumption on driving simulation performance.

    Science.gov (United States)

    Leung, Sumie; Croft, Rodney J; Jackson, Melinda L; Howard, Mark E; McKenzie, Raymond J

    2012-01-01

    The present study compared the effects of a variety of mobile phone usage conditions to different levels of alcohol intoxication on simulated driving performance and psychomotor vigilance. Twelve healthy volunteers participated in a crossover design in which each participant completed a simulated driving task on 2 days, separated by a 1-week washout period. On the mobile phone day, participants performed the simulated driving task under each of 4 conditions: no phone usage, a hands-free naturalistic conversation, a hands-free cognitively demanding conversation, and texting. On the alcohol day, participants performed the simulated driving task at four different blood alcohol concentration (BAC) levels: 0.00, 0.04, 0.07, and 0.10. Driving performance was assessed by variables including time within target speed range, time spent speeding, braking reaction time, speed deviation, and lateral lane position deviation. In the BAC 0.07 and 0.10 alcohol conditions, participants spent less time in the target speed range and more time speeding and took longer to brake in the BAC 0.04, 0.07, and 0.10 than in the BAC 0.00 condition. In the mobile phone condition, participants took longer to brake in the natural hands-free conversation, cognitively demanding hands-free conversation and texting conditions and spent less time in the target speed range and more time speeding in the cognitively demanding, hands-free conversation, and texting conditions. When comparing the 2 conditions, the naturalistic conversation was comparable to the legally permissible BAC level (0.04), and the cognitively demanding and texting conversations were similar to the BAC 0.07 to 0.10 results. The findings of the current laboratory study suggest that very simple conversations on a mobile phone may not represent a significant driving risk (compared to legally permissible BAC levels), whereas cognitively demanding, hands-free conversation, and particularly texting represent significant risks to driving.

  6. Effects of Pile Driving on the Residency and Movement of Tagged Reef Fish.

    Directory of Open Access Journals (Sweden)

    Joseph D Iafrate

    Full Text Available The potential effects of pile driving on fish populations and commercial fisheries have received significant attention given the prevalence of pile driving occurring in coastal habitats throughout the world. Behavioral impacts of sound generated from these activities on fish typically have a greater area of influence than physical injury, and may therefore adversely affect a greater portion of the local population. This study used acoustic telemetry to assess the movement, residency, and survival of 15 sheepshead (Archosargus probatocephalus and 10 grey snapper (Lutjanus griseus in Port Canaveral, Florida, USA, in response to 35 days of pile driving at a wharf complex. No obvious signs of mortality or injury to tagged fish were evident from the data. Received sound pressure levels from pile strikes on the interior of the wharf, where reef fish primarily occur, were on average 152-157 dB re 1 μPa (peak. No significant decrease in sheepshead daytime residency was observed during pile driving within the central portion of the wharf and area of highest sound exposure, and no major indicators of displacement from the exposure wharf with the onset of pile driving were observed. There was evidence of potential displacement from the exposure wharf that coincided with the start of pile driving observed for 2 out of 4 grey snapper, along with a decrease in daytime residency for a subset of this species with high site fidelity prior to the event. Results indicate that snapper may be more likely to depart an area of pile driving disturbance more readily than sheepshead, but were less at risk for behavioral impact given the lower site fidelity of this species.

  7. Het effect van begeleid rijden (2toDrive) op zelfgerapporteerde ongevallen en overtredingen : een vragenlijstonderzoek onder alle jonge automobilisten in Nederland.

    NARCIS (Netherlands)

    Schagen, I.N.L.G. van Korving, H. & Craen, S. de

    2015-01-01

    The effect of accompanied driving (2toDrive) on self-reported crashes and violations : a questionnaire survey among all young drivers in the Netherlands. In 2011, a six-year accompanied driving pilot under the name of 2toDrive was launched in the Netherlands: young people can get their driving

  8. A systematic review of the effect of various interventions on reducing fatigue and sleepiness while driving

    Directory of Open Access Journals (Sweden)

    Seyed Saeed Hashemi Nazari

    2017-10-01

    Full Text Available Purpose: To identify and appraise the published studies assessing interventions accounting for reducing fatigue and sleepiness while driving. Methods: This systematic review searched the following electronic databases: Medline, Science direct, Scopus, EMBASE, PsycINFO, Transport Database, Cochrane, BIOSIS, ISI Web of Knowledge, specialist road injuries journals and the Australian Transport and Road Index database. Additional searches included websites of relevant organizations, reference lists of included studies, and issues of major injury journals published within the past 15 years. Studies were included if they investigated interventions/exposures accounting for reducing fatigue and sleepiness as the outcome, measured any potential interventions for mitigation of sleepiness and were written in English. Meta-analysis was not attempted because of the heterogeneity of the included studies. Results: Of 63 studies identified, 18 met the inclusion criteria. Based on results of our review, many interventions in the world have been used to reduce drowsiness while driving such as behavioral (talking to passengers, face washing, listening to the radio, no alcohol use, limiting the driving behavior at the time of 12 p.m. – 6 a.m. etc, educational interventions and also changes in the environment (such as rumble strips, chevrons, variable message signs, etc. Meta-analysis on the effect of all these interventions was impossible due to the high heterogeneity in methodology, effect size and interventions reported in the assessed studies. Conclusion: Results of present review showed various interventions in different parts of the world have been used to decrease drowsy driving. Although these interventions can be used in countries with high incidence of road traffic accidents, precise effect of each intervention is still unknown. Further studies are required for comparison of the efficiency of each intervention and localization of each intervention

  9. Predator diversity effects in an exotic freshwater food web.

    Science.gov (United States)

    Naddafi, Rahmat; Rudstam, Lars G

    2013-01-01

    Cascading trophic interactions are often defined as the indirect effects of a predator on primary producers through the effect of the predator on herbivores. These effects can be both direct through removal of herbivores [density-mediated indirect interactions (DMIIs)] or indirect through changes in the behavior of the herbivores [trait-mediated indirect interactions (TMIIs)]. How the relative importance of these two indirect interactions varies with predator diversity remains poorly understood. We tested the effect of predator diversity on both TMIIs and DMIIs on phytoplankton using two competitive invasive dreissenid mussel species (zebra mussel and quagga mussel) as the herbivores and combinations of one, two or all three species of the predators pumpkinseed sunfish, round goby, and rusty crayfish. Predators had either direct access to mussels and induced both TMII and DMII, or no direct access and induced only TMII through the presence of risk cues. In both sets of treatments, the predators induced a trophic cascade which resulted in more phytoplankton remaining with predators present than with only mussels present. The trophic cascade was weaker in three-predator and two-predator treatments than in one-predator treatments when predators had direct access to dreissenids (DMIIs and TMIIs). Crayfish had higher cascading effects on phytoplankton than both pumpkinseed and round goby. Increased predator diversity decreased the strength of DMIIs but had no effect on the strength of TMIIs. The strength of TMIIs was higher with zebra than quagga mussels. Our study suggests that inter-specific interference among predators in multi-species treatments weakens the consumptive cascading effects of predation on lower trophic levels whereas the importance of predator diversity on trait mediated effects depends on predator identity.

  10. Predator diversity effects in an exotic freshwater food web.

    Directory of Open Access Journals (Sweden)

    Rahmat Naddafi

    Full Text Available Cascading trophic interactions are often defined as the indirect effects of a predator on primary producers through the effect of the predator on herbivores. These effects can be both direct through removal of herbivores [density-mediated indirect interactions (DMIIs] or indirect through changes in the behavior of the herbivores [trait-mediated indirect interactions (TMIIs]. How the relative importance of these two indirect interactions varies with predator diversity remains poorly understood. We tested the effect of predator diversity on both TMIIs and DMIIs on phytoplankton using two competitive invasive dreissenid mussel species (zebra mussel and quagga mussel as the herbivores and combinations of one, two or all three species of the predators pumpkinseed sunfish, round goby, and rusty crayfish. Predators had either direct access to mussels and induced both TMII and DMII, or no direct access and induced only TMII through the presence of risk cues. In both sets of treatments, the predators induced a trophic cascade which resulted in more phytoplankton remaining with predators present than with only mussels present. The trophic cascade was weaker in three-predator and two-predator treatments than in one-predator treatments when predators had direct access to dreissenids (DMIIs and TMIIs. Crayfish had higher cascading effects on phytoplankton than both pumpkinseed and round goby. Increased predator diversity decreased the strength of DMIIs but had no effect on the strength of TMIIs. The strength of TMIIs was higher with zebra than quagga mussels. Our study suggests that inter-specific interference among predators in multi-species treatments weakens the consumptive cascading effects of predation on lower trophic levels whereas the importance of predator diversity on trait mediated effects depends on predator identity.

  11. Effectiveness of a visual attention retraining program on the driving performance of clients with stroke.

    Science.gov (United States)

    Mazer, Barbara L; Sofer, Susan; Korner-Bitensky, Nicol; Gelinas, Isabelle; Hanley, James; Wood-Dauphinee, Sharon

    2003-04-01

    To compare the effectiveness of a visual attention retraining program using the Useful Field of View (UFOV) with a traditional visuoperception treatment program on the driving performance of clients with stroke. Randomized controlled trial. Rehabilitation hospital located in Quebec, Canada. Ninety-seven individuals referred for driving evaluation after a stroke. Participants were randomized to receive 20 sessions of either UFOV training of visual processing speed, divided attention, and selective attention or traditional computerized visuoperception retraining. Subjects were evaluated with an on-road driving evaluation, visuoperception tests, and the Test of Everyday Attention. An occupational therapist unaware of group assignment conducted all evaluations. Eighty-four participants completed the outcome evaluation. There were no significant differences between groups on any of the outcome measures. There was, however, almost a 2-fold increase (52.4% vs 28.6%) in the rate of success on the on-road driving evaluation after UFOV training for subjects with right-sided lesions. Rehabilitation that targets visual attention skills was not significantly more beneficial than traditional perceptual training in improving the outcome of an on-road driving evaluation. However, results suggest a potential improvement for subjects with right-sided lesions, indicating that training must target specific skills.

  12. Moessbauer polarimetry using fluosilicates. Double motion drive and effective thickness measurements

    Energy Technology Data Exchange (ETDEWEB)

    Henry, M; Varret, F [Centre Universitaire du Mans, 72 (France)

    1977-12-16

    Calculations are made and spectra are obtained on linear experiments using single crystals. The energy coincidence between the source and the polarizer is achieved by using a double motion drive which moves the source at a constant velocity. Such an experiment provides an accurate determination of both the polarizer and the analyzer effective thicknesses.

  13. X-ray geometrical smoothing effect in indirect x-ray-drive implosion

    International Nuclear Information System (INIS)

    Mochizuki, Takayasu; Sakabe, Shuji; Yamanaka, Chiyoe

    1983-01-01

    X-ray geometrical smoothing effect in indirect X-ray drive pellet implosion for inertial confinement fusion has been numerically analyzed. Attainable X-ray driven ablation pressure has been found to be coupled with X-ray irradiation uniformity. (author)

  14. Drink-driving convictions and the effect of lowering the BAC levels

    DEFF Research Database (Denmark)

    Christoffersen, Mogens

    .g. disadvantages during adolescence, severe psychological problems, prior criminal history, living in rural vs. metropolitan area, and their present social position, e.g. educational background). In order to evaluate the effect of changed legislation on the incidence of first-time drink-driving convictions among...

  15. Soil compaction effects of forwarding and its relationship with 6- and 8-wheel drive machines

    Science.gov (United States)

    Fernando Seixas; Tim. McDonald

    1997-01-01

    A study was done to determine the impact, if any, of a range of drive train options on the soil compaction effects of forwarders. The purpose of the study was to evaluate the cost of optional forwarder equipment versus its ability to reduce detrimental soil physical property changes. Tests were done on forwarders equipped with wide and narrow tires, rear steel tracks,...

  16. Effect of pile-driving sounds on the survival of larval fish (abstract)

    NARCIS (Netherlands)

    Bolle, L.; Jong, C.A.F. de; Bierman, S.M.; Beek, P.J.G. van; Wessels, P.W.; Blom, E.; Damme, C.J.G. van; Winter, H.V.; Dekeling, R.P.A.

    2013-01-01

    In view of the rapid extension of offshore wind farms, there is an urgent need to improve our knowledge on possible adverse effects of underwater sound generated by pile-driving. Mortality and injuries have been observed in fish exposed to loud impulse sounds, but knowledge on the sound levels at

  17. Effects of passive components on the input current interharmonics of adjustable-speed drives

    DEFF Research Database (Denmark)

    Soltani, Hamid; Blaabjerg, Frede; Zare, Firuz

    2016-01-01

    Current and voltage source Adjustable Speed Drives (ASDs) exert distortion current into the grid, which may produce some interharmonic components other than the characteristic harmonic components. This paper studies the effects of passive components on the input current interharmonics of adjustable...

  18. Seemingly irrational driving behavior model: The effect of habit strength and anticipated affective reactions.

    Science.gov (United States)

    Chung, Yi-Shih

    2015-09-01

    An increasing amount of evidence suggests that aberrant driving behaviors are not entirely rational. On the basis of the dual-process theory, this study postulates that drivers may learn to perform irrational aberrant driving behaviors, and these behaviors could be derived either from a deliberate or an intuitive decision-making approach. Accordingly, a seemingly irrational driving behavior model is proposed; in this model, the theory of planned behavior (TPB) was adopted to represent the deliberate decision-making mechanism, and habit strength was incorporated to reflect the intuitive decision process. A multiple trivariate mediation structure was designed to reflect the process through which driving behaviors are learned. Anticipated affective reactions (AARs) were further included to examine the effect of affect on aberrant driving behaviors. Considering the example of speeding behaviors, this study developed scales and conducted a two-wave survey of students in two departments at a university in Northern Taiwan. The analysis results show that habit strength consists of multiple aspects, and frequency of past behavior cannot be a complete repository for accumulating habit strength. Habit strength appeared to be a crucial mediator between intention antecedents (e.g., attitude) and the intention itself. Including habit strength in the TPB model enhanced the explained variance of speeding intention by 26.7%. In addition, AARs were different from attitudes; particularly, young drivers tended to perform speeding behaviors to reduce negative feelings such as regret. The proposed model provides an effective alternative approach for investigating aberrant driving behaviors; corresponding countermeasures are discussed. Copyright © 2015 Elsevier Ltd. All rights reserved.

  19. The effects of anti-speeding advertisements on the simulated driving behaviour of young drivers.

    Science.gov (United States)

    Plant, Bernice R C; Irwin, Julia D; Chekaluk, Eugene

    2017-03-01

    Recent examinations of road safety communications, including anti-speeding advertisements, have considered the differential effects of positive and negative emotional appeals on driver behaviour. However, empirical evaluations of anti-speeding messages have largely relied on measures of viewers' reported intentions to comply with speed limits and the self-reported driving behaviour of viewers post-exposure, which might not be indicative of the direct effects that these messages have on real-world driving behaviour. The current research constitutes a first empirical evaluation of different real-world anti-speeding advertisements, as measured by their effects on young drivers' speeding behaviour, using a driving simulator. Licensed drivers (N=116) aged 17-25 years completed driving measures prior to, immediately following, and 7-10days after viewing one of four social marketing advertisements. Results indicated that young drivers' average driving speeds were modestly reduced immediately after they viewed an anti-speeding advertisement that depicted social consequences for speeding and employed a positive emotional appeal when compared to an emotion-matched control advertisement; however, this effect was not found for the anti-speeding advertisement depicting a crash. Interestingly, the results based on reported intentions to reduce speeding predicted the opposite pattern of results. However, there was no evidence that the immediate changes to speeding were maintained 7-10days later, and prompts during Phase 2 did not appear to have an effect. The implications of these findings for road safety advertisements targeting young drivers are discussed. Copyright © 2017 Elsevier Ltd. All rights reserved.

  20. Effects of central nervous system drugs on driving: speed variability versus standard deviation of lateral position as outcome measure of the on-the-road driving test.

    Science.gov (United States)

    Verster, Joris C; Roth, Thomas

    2014-01-01

    The on-the-road driving test in normal traffic is used to examine the impact of drugs on driving performance. This paper compares the sensitivity of standard deviation of lateral position (SDLP) and SD speed in detecting driving impairment. A literature search was conducted to identify studies applying the on-the-road driving test, examining the effects of anxiolytics, antidepressants, antihistamines, and hypnotics. The proportion of comparisons (treatment versus placebo) where a significant impairment was detected with SDLP and SD speed was compared. About 40% of 53 relevant papers did not report data on SD speed and/or SDLP. After placebo administration, the correlation between SDLP and SD speed was significant but did not explain much variance (r = 0.253, p = 0.0001). A significant correlation was found between ΔSDLP and ΔSD speed (treatment-placebo), explaining 48% of variance. When using SDLP as outcome measure, 67 significant treatment-placebo comparisons were found. Only 17 (25.4%) were significant when SD speed was used as outcome measure. Alternatively, for five treatment-placebo comparisons, a significant difference was found for SD speed but not for SDLP. Standard deviation of lateral position is a more sensitive outcome measure to detect driving impairment than speed variability.

  1. Soil fertility and species traits, but not diversity, drive productivity and biomass stocks in a Guyanese tropical rainforest

    NARCIS (Netherlands)

    Sande, van der M.T.; Arets, E.J.M.M.; Pena Claros, M.; Hoosbeek, M.R.; Caceres-Siani, Yasmani; Hout, van de P.; Poorter, L.

    2018-01-01

    1.Tropical forests store and sequester large amounts of carbon in above- and below-ground plant biomass and soil organic matter (SOM), but how these are driven by abiotic and biotic factors remains poorly understood.
    2.Here, we test the effects of abiotic factors (light variation, caused by

  2. On the effective turbulence driving mode of molecular clouds formed in disc galaxies

    Science.gov (United States)

    Jin, Keitaro; Salim, Diane M.; Federrath, Christoph; Tasker, Elizabeth J.; Habe, Asao; Kainulainen, Jouni T.

    2017-07-01

    We determine the physical properties and turbulence driving mode of molecular clouds formed in numerical simulations of a Milky Way-type disc galaxy with parsec-scale resolution. The clouds form through gravitational fragmentation of the gas, leading to average values for mass, radii and velocity dispersion in good agreement with observations of Milky Way clouds. The driving parameter (b) for the turbulence within each cloud is characterized by the ratio of the density contrast (σ _{ρ /ρ _0}) to the average Mach number (M) within the cloud, b=σ _{ρ /ρ _0}/M. As shown in previous works, b ˜ 1/3 indicates solenoidal (divergence-free) driving and b ˜ 1 indicates compressive (curl-free) driving. We find that the average b value of all the clouds formed in the simulations has a lower limit of b > 0.2. Importantly, we find that b has a broad distribution, covering values from purely solenoidal to purely compressive driving. Tracking the evolution of individual clouds reveals that the b value for each cloud does not vary significantly over their lifetime. Finally, we perform a resolution study with minimum cell sizes of 8, 4, 2 and 1 pc and find that the average b value increases with increasing resolution. Therefore, we conclude that our measured b values are strictly lower limits and that a resolution better than 1 pc is required for convergence. However, regardless of the resolution, we find that b varies by factors of a few in all cases, which means that the effective driving mode alters significantly from cloud to cloud.

  3. Measuring employee perception on the effects of cultural diversity at work: development of the Benefits and Threats of Diversity Scale

    NARCIS (Netherlands)

    Hofhuis, Joep; van der Zee, Karen; Otten, Sabine

    2015-01-01

    This paper describes the development and validation of the Benefits and Threats of Diversity Scale (BTDS), an instrument which measures how employees perceive the effects of cultural diversity in the workplace. By analyzing employees’ perceptions, organizations may be able to communicate more

  4. Measuring employee perception on the effects of cultural diversity at work: development of the benefits and threats of diversity scale.

    NARCIS (Netherlands)

    Hofhuis, J.; van der Zee, K.I.; Otten, S.

    2015-01-01

    This paper describes the development and validation of the Benefits and Threats of Diversity Scale (BTDS), an instrument which measures how employees perceive the effects of cultural diversity in the workplace. By analyzing employees’ perceptions, organizations may be able to communicate more

  5. Measuring employee perception on the effects of cultural diversity at work : development of the Benefits and Threats of Diversity Scale

    NARCIS (Netherlands)

    Hofhuis, Joep; van der Zee, Karen I.; Otten, Sabine

    2015-01-01

    This paper describes the development and validation of the Benefits and Threats of Diversity Scale (BTDS), an instrument which measures how employees perceive the effects of cultural diversity in the workplace. By analyzing employees’ perceptions, organizations may be able to communicate more

  6. Effect of hygiene communication on emptying of urine diversion toilets

    CSIR Research Space (South Africa)

    Moilwa, N

    2006-11-01

    Full Text Available is dependent on microbial species present and their count per gram. According to Austin (2000) pathogens die-off in a urine diversion toilet in South Africa, in other words the presence of microbial species and their count per gram is determined by storage... during the implementation of this project. The purpose was to determine the effectiveness of the vault emptying education given during the health and hygiene education programme. The external consultant that implemented the health and hygiene...

  7. The Effects of Caffeine Use on Driving Safety Among Truck Drivers Who Are Habitual Caffeine Users.

    Science.gov (United States)

    Heaton, Karen; Griffin, Russell

    2015-08-01

    The purpose of this study was to describe caffeine use among a group of habitual caffeine users, truck drivers, and to explore the associations between caffeine use and critical safety events by age in the naturalistic work setting. A secondary analysis of existing data from the Naturalistic Truck Driving Study was conducted. Analyses focused on the association between sleep and caffeine consumption by duty status, comparisons of sleep and caffeine use by age, and the associations between caffeine use and safety-critical events (SCEs). Findings indicated differences in caffeine use by duty status. However, no difference in sleep time by duty status, or between sleep time and caffeine use was found regardless of when the caffeine was consumed during the 5 hours prior to sleep. Sleep time did not vary significantly by age, although increasing age was associated with decreased caffeine use. Overall, a 6% reduction in the rate of SCEs per eight ounces of caffeinated beverage consumed was found. This study makes a unique scientific contribution because it uses real-time observations of truckers in the naturalistic work setting. It also does not involve caffeine withdrawal but rather an investigation of the effects of the naturalistic consumption of caffeine on sleep and driving performance. Findings suggest that caffeine use among habitual users offers a protective effect for safety-critical driving events. Occupational health nurses may use this information to counsel workers in the use of caffeine to enhance driving safety. © 2015 The Author(s).

  8. The effect of billboard design specifications on driving: A pilot study.

    Science.gov (United States)

    Marciano, Hadas; Setter, Pe'erly

    2017-07-01

    Decades of research on the effects of advertising billboards on road accident rates, driver performance, and driver visual scanning behavior, has produced no conclusive findings. We suggest that road safety researchers should shift their focus and attempt to identify the billboard characteristics that are most distracting to drivers. This line of research may produce concrete guidelines for permissible billboards that would be likely to reduce the influence of the billboards on road safety. The current study is a first step towards this end. A pool of 161 photos of real advertising billboards was used as stimuli within a triple task paradigm designed to simulate certain components of driving. Each trial consisted of one ongoing tracking task accompanied by two additional concurrent tasks: (1) billboard observation task; and (2) circle color change identification task. Five clusters of billboards, identified by conducting a cluster analysis of their graphic content, were used as a within variable in one-way ANOVAs conducted on performance level data collected from the multiple tasks. Cluster 5, labeled Loaded Billboards, yielded significantly deteriorated performance on the tracking task. Cluster 4, labeled Graphical Billboards, yielded deteriorated performance primarily on the color change identification task. Cluster 3, labeled Minimal Billboards, had no effect on any of these tasks. We strongly recommend that these clusters be systematically explored in experiments involving additional real driving settings, such as driving simulators and field studies. This will enable validation of the current results and help incorporate them into real driving situations. Copyright © 2017. Published by Elsevier Ltd.

  9. Differential residual effects of zaleplon and zopiclone on actual driving: a comparison with a low dose of alcohol.

    Science.gov (United States)

    Vermeeren, Annemiek; Riedel, Wim J; van Boxtel, Martin P J; Darwish, Mona; Paty, Isabelle; Patat, Alain

    2002-03-15

    To compare residual effects of zaleplon 10 mg, zopiclone 7.5 mg, and placebo, and a social dose of alcohol on car driving, memory, and psychomotor performance. Two-part placebo controlled, crossover study. Part 1 was single blind, Part 2 double blind. University research institute. Thirty healthy volunteers (15 men and 15 women, mean age 32 +/- 7 years) In Part 1 alcohol and alcohol-placebo drinks were administered around noon. In Part 2 single oral doses of zaleplon 10 mg, zopiclone 7.5 mg and placebo were administered at bedtime. A highway driving test, laboratory tests of word learning, critical tracking and divided attention, and subjective assessments of sleep, mood, and effects of treatments on driving. Driving started 40 minutes after a second alcohol dose in Part 1, and 10 hours after drug intake in Part 2. The results demonstrated that alcohol, at average plasma concentrations of approximately 0.030 g/dl, significantly impaired performance in all tests. Zaleplon's residual effects did not differ significantly from those of placebo in any test. In contrast, zopiclone had significant residual effects on driving, divided attention, and memory. The magnitude of impairment in the driving test observed the morning after zopiclone 7.5 mg was twice that observed with alcohol. Zaleplon 10 mg has no residual effects on driving when taken at bedtime, 10 hours before driving. In contrast, zopiclone 7.5 mg can cause marked residual impairment. Patients should be advised to avoid driving the morning after zopiclone administration.

  10. Effects of different blood alcohol concentrations and post-alcohol impairment on driving behavior and task performance.

    Science.gov (United States)

    Liu, Yung-Ching; Ho, Chin Heng

    2010-08-01

    A study using simulator methodology was conducted to investigate the effects of (1) different blood alcohol concentrations (BAC) of 0, 0.05, 0.08, and 0.10 percent and (2) post-alcohol impairment (where BAC approximately 0%) on driving behavior and subsidiary cognitive task performance. Two driving sessions were investigated, that is, drunk driving and post-alcohol driving, with each requiring approximately 20 min of driving. In addition to driving safely, participants were instructed to perform the critical flicker fusion (CFF) test and completed the NASA-TLX mental workload questionnaire. Eight licensed drivers (6 males, 2 females) participated in this 2 (road complexities) x 2 (simulated driving sessions) x 4 (levels of BAC) within-subjects experiment. The study revealed that higher BAC levels were associated with lower performing driving behavior. The driver's mental workload reached the highest values in the post-alcohol session. In terms of tasks involving divided attention, the traffic sign distance estimation showed significant deterioration with increased BAC levels. The relationship between drunk-driving behavior and alcohol dosage was supported in this study. Noticeably, no significant difference was found between drunk driving and post-alcohol driving, indicating that even in the post-alcohol situation, the impairment still remained significant enough to jeopardize traffic safety as much as it does in the case of drunk driving. In real-life situations, adopting a rest-time strategy to avoid post-alcohol impairment effects may not be the most appropriate solution by drivers; rather, drivers should be given some tests to verify the probability of post-alcohol effects on driving.

  11. Improving long term driving comfort by taking breaks - How break activity affects effectiveness.

    Science.gov (United States)

    Sammonds, George M; Mansfield, Neil J; Fray, Mike

    2017-11-01

    During long duration journeys, drivers are encouraged to take regular breaks. The benefits of breaks have been documented for safety; breaks may also be beneficial for comfort. The activity undertaken during a break may influence its effectiveness. Volunteers completed 3 journeys on a driving simulator. Each 130 min journey included a 10 min break after the first hour. During the break volunteers either stayed seated, left the simulator and sat in an adjacent room, or took a walk on a treadmill. The results show a reduction in driver discomfort during the break for all 3 conditions, but the effectiveness of the break was dependent on activity undertaken. Remaining seated in the vehicle provided some improvement in comfort, but more was experienced after leaving the simulator and sitting in an adjacent room. The most effective break occurred when the driver walked for 10 min on a treadmill. The benefits from taking a break continued until the end of the study (after a further hour of driving), such that comfort remained the best after taking a walk and worst for those who remained seated. It is concluded that taking a break and taking a walk is an effective method for relieving driving discomfort. Copyright © 2017 Elsevier Ltd. All rights reserved.

  12. Effects of in-car support on mental workload and driving performance of older drivers.

    Science.gov (United States)

    Davidse, Ragnhild J; Hagenzieker, Marjan P; van Wolffelaar, Peter C; Brouwer, Wiebo H

    2009-08-01

    This study examined the extent to which driving performance of 10 older (70-88 years old) and 30 younger participants (30-50 years old) improves as a result of support by a driver assistance system. Various studies have indicated that advanced driver assistance systems (ADAS) may provide tailored assistance for older drivers and thereby improve their safe mobility. While drivers followed an urban route in a driving simulator, an ADAS provided them with prior knowledge on the next intersection. The system was evaluated in terms of effects on workload and safety performance. Messages informing drivers about the right-of-way regulation, obstructed view of an intersection, and safe gaps to join or cross traffic streams led to safer driving performance. A message regarding an unexpected one-way street led to fewer route errors. In general, effects were the same for all age groups. Workload was not reduced by the support system. The evaluated support system shows promising effects for all age groups. Longer evaluation periods are needed to determine long-term effects. The messages provided by the evaluated system are currently not provided by existing ADAS such as advanced cruise control and navigation systems, but they could possibly be added to them in the future.

  13. Effects of Consuming a Low Dose of Alcohol with Mixers Containing Carbohydrate or Artificial Sweetener on Simulated Driving Performance

    Directory of Open Access Journals (Sweden)

    Bryce Brickley

    2018-03-01

    Full Text Available The Australian National Drug and Alcohol Research Centre (NDARC devised gender-based drinking recommendations to ensure blood or equivalized breath alcohol concentrations (BrAC remain <0.050%. However, these may be inappropriate for individuals consuming alcohol without carbohydrate (CHO, which results in higher BrACs. This study investigated the effects of ingesting alcohol with and without CHO on BrACs and simulated driving performance. Thirty-two participants (16 males; age: 23 ± 6 years completed two randomized single-blinded trials. Participants performed a baseline drive (Drive 1, then an experimental drive (Drive 2, following alcohol consumption (males: 20 g; females: 10 g. Alcoholic beverages contained either 25 g sucrose or aspartame (AS. Driving performance was assessed using lateral control (standard deviation of lane position [SDLP] and number of lane departures and risk-taking (number of overtaking maneuvers and maximum overtaking speed. BrAC and subjective ratings (e.g., intoxication were also assessed. BrAC was significantly lower as Drive 2 commenced with CHO compared to AS (0.022 ± 0.008% vs. 0.030 ± 0.011%. Two males provided BrACs >0.050% with AS. Neither beverage influenced changes to simulated driving performance. Ingesting alcohol in quantities advised by the NDARC results in no detectable simulated driving impairment. However, the likelihood of exceeding the legal drink-driving BrAC is increased when alcohol is consumed with artificially-sweetened mixers.

  14. Alpha effect of Alfven waves and current drive in reversed field pinches

    International Nuclear Information System (INIS)

    Litwin, C.; Prager, S.C.

    1997-10-01

    Circularly polarized Alfven waves give rise to an α-dynamo effect that can be exploited to drive parallel current. In a open-quotes laminarclose quotes magnetic the effect is weak and does not give rise to significant currents for realistic parameters (e.g., in tokamaks). However, in reversed field pinches (RFPs) in which magnetic field in the plasma core is stochastic, a significant enhancement of the α-effect occurs. Estimates of this effect show that it may be a realistic method of current generation in the present-day RFP experiments and possibly also in future RFP-based fusion reactors

  15. Improving long term driving comfort by taking breaks - how break activity affects effectiveness

    OpenAIRE

    Sammonds, GM; Mansfield, NJ; Fray, M

    2017-01-01

    During long duration journeys, drivers are encouraged to take regular breaks. The benefits of breaks have been documented for safety; breaks may also be beneficial for comfort. The activity undertaken during a break may influence its effectiveness. Volunteers completed 3 journeys on a driving simulator. Each 130 min journey included a 10 min break after the first hour. During the break volunteers either stayed seated, left the simulator and sat in an adjacent room, or took a walk on a treadmi...

  16. Sensitivity and validity of psychometric tests for assessing driving impairment: effects of sleep deprivation.

    Science.gov (United States)

    Jongen, Stefan; Perrier, Joy; Vuurman, Eric F; Ramaekers, Johannes G; Vermeeren, Annemiek

    2015-01-01

    To assess drug induced driving impairment, initial screening is needed. However, no consensus has been reached about which initial screening tools have to be used. The present study aims to determine the ability of a battery of psychometric tests to detect performance impairing effects of clinically relevant levels of drowsiness as induced by one night of sleep deprivation. Twenty four healthy volunteers participated in a 2-period crossover study in which the highway driving test was conducted twice: once after normal sleep and once after one night of sleep deprivation. The psychometric tests were conducted on 4 occasions: once after normal sleep (at 11 am) and three times during a single night of sleep deprivation (at 1 am, 5 am, and 11 am). On-the-road driving performance was significantly impaired after sleep deprivation, as measured by an increase in Standard Deviation of Lateral Position (SDLP) of 3.1 cm compared to performance after a normal night of sleep. At 5 am, performance in most psychometric tests showed significant impairment. As expected, largest effect sizes were found on performance in the Psychomotor Vigilance Test (PVT). Large effects sizes were also found in the Divided Attention Test (DAT), the Attention Network Test (ANT), and the test for Useful Field of View (UFOV) at 5 and 11 am during sleep deprivation. Effects of sleep deprivation on SDLP correlated significantly with performance changes in the PVT and the DAT, but not with performance changes in the UFOV. From the psychometric tests used in this study, the PVT and DAT seem most promising for initial evaluation of drug impairment based on sensitivity and correlations with driving impairment. Further studies are needed to assess the sensitivity and validity of these psychometric tests after benchmark sedative drug use.

  17. Sensitivity and validity of psychometric tests for assessing driving impairment: effects of sleep deprivation.

    Directory of Open Access Journals (Sweden)

    Stefan Jongen

    Full Text Available To assess drug induced driving impairment, initial screening is needed. However, no consensus has been reached about which initial screening tools have to be used. The present study aims to determine the ability of a battery of psychometric tests to detect performance impairing effects of clinically relevant levels of drowsiness as induced by one night of sleep deprivation.Twenty four healthy volunteers participated in a 2-period crossover study in which the highway driving test was conducted twice: once after normal sleep and once after one night of sleep deprivation. The psychometric tests were conducted on 4 occasions: once after normal sleep (at 11 am and three times during a single night of sleep deprivation (at 1 am, 5 am, and 11 am.On-the-road driving performance was significantly impaired after sleep deprivation, as measured by an increase in Standard Deviation of Lateral Position (SDLP of 3.1 cm compared to performance after a normal night of sleep. At 5 am, performance in most psychometric tests showed significant impairment. As expected, largest effect sizes were found on performance in the Psychomotor Vigilance Test (PVT. Large effects sizes were also found in the Divided Attention Test (DAT, the Attention Network Test (ANT, and the test for Useful Field of View (UFOV at 5 and 11 am during sleep deprivation. Effects of sleep deprivation on SDLP correlated significantly with performance changes in the PVT and the DAT, but not with performance changes in the UFOV.From the psychometric tests used in this study, the PVT and DAT seem most promising for initial evaluation of drug impairment based on sensitivity and correlations with driving impairment. Further studies are needed to assess the sensitivity and validity of these psychometric tests after benchmark sedative drug use.

  18. Effects of two doses of methylphenidate on simulator driving performance in adults with attention deficit hyperactivity disorder.

    Science.gov (United States)

    Barkley, Russell A; Murphy, Kevin R; O'Connell, Trisha; Connor, Daniel F

    2005-01-01

    Numerous studies have documented an increased frequency of vehicular crashes, traffic citations, driving performance deficits, and driving-related cognitive impairments in teens and adults with attention deficit hyperactivity disorder. The present study evaluated the effects of two single, acute doses of methylphenidate (10 and 20 mg) and a placebo on the driving performance of 53 adults with ADHD (mean age=37 years, range=18-65) using a virtual reality driving simulator, examiner and self-ratings of simulator performance, and a continuous performance test (CPT) to evaluate attention and inhibition. A double-blind, drug-placebo, within-subjects crossover design was used in which all participants were tested at baseline and then experienced all three drug conditions. A significant beneficial effect for the high dose of medication was observed on impulsiveness on CPT, variability of steering in the standard driving course, and driving speed during the obstacle course. A beneficial effect of the low dose of medication also was evident on turn signal use during the standard driving course. An apparent practice effect was noted on some of the simulator measures between the baseline and subsequent testing sessions that may have interacted with and thereby obscured drug effects on those measures. The results, when placed in the context of prior studies of stimulants on driving performance, continue to recommend their clinical use as one means of reducing the driving risks in ADHD teens and adults. Given the significantly higher risk of adverse driving outcomes associated with ADHD, industry needs to better screen for ADHD among employees who drive as part of employment so as to improve safety and reduce costs. Use of stimulants to treat the adult ADHD driver may reduce safety risks.

  19. Effect of meal glycemic load and caffeine consumption on prolonged monotonous driving performance.

    Science.gov (United States)

    Bragg, Christopher; Desbrow, Ben; Hall, Susan; Irwin, Christopher

    2017-11-01

    Monotonous driving involves low levels of stimulation and high levels of repetition and is essentially an exercise in sustained attention and vigilance. The aim of this study was to determine the effects of consuming a high or low glycemic load meal on prolonged monotonous driving performance. The effect of consuming caffeine with a high glycemic load meal was also examined. Ten healthy, non-diabetic participants (7 males, age 51±7yrs, mean±SD) completed a repeated measures investigation involving 3 experimental trials. On separate occasions, participants were provided one of three treatments prior to undertaking a 90min computer-based simulated drive. The 3 treatment conditions involved consuming: (1) a low glycemic load meal+placebo capsules (LGL), (2) a high glycemic load meal+placebo capsules (HGL) and (3) a high glycemic load meal+caffeine capsules (3mgkg -1 body weight) (CAF). Measures of driving performance included lateral (standard deviation of lane position (SDLP), average lane position (AVLP), total number of lane crossings (LC)) and longitudinal (average speed (AVSP) and standard deviation of speed (SDSP)) vehicle control parameters. Blood glucose levels, plasma caffeine concentrations and subjective ratings of sleepiness, alertness, mood, hunger and simulator sickness were also collected throughout each trial. No difference in either lateral or longitudinal vehicle control parameters or subjective ratings were observed between HGL and LGL treatments. A significant reduction in SDLP (0.36±0.20m vs 0.41±0.19m, p=0.004) and LC (34.4±31.4 vs 56.7±31.5, p=0.018) was observed in the CAF trial compared to the HGL trial. However, no differences in AVLP, AVSP and SDSP or subjective ratings were detected between these two trials (p>0.05). Altering the glycemic load of a breakfast meal had no effect on measures of monotonous driving performance in non-diabetic adults. Individuals planning to undertake a prolonged monotonous drive following consumption of a

  20. Considering diversity: The positive effects of considerate leadership in diverse teams

    NARCIS (Netherlands)

    Homan, A.C.; Greer, L.L.

    2013-01-01

    Three studies examined the role of leader consideration in diverse teams. Based on the categorization-elaboration model, we argue that leader consideration can address the negative group processes that result from categorization processes in diverse teams as well as influence the perceptions of the

  1. Fishing drives declines in fish parasite diversity and has variable effects on parasite abundance.

    Science.gov (United States)

    Wood, Chelsea L; Sandin, Stuart A; Zgliczynski, Brian; Guerra, Ana Sofía; Micheli, Fiorenza

    2014-07-01

    Despite the ubiquity and ecological importance of parasites, relatively few studies have assessed their response to anthropogenic environmental change. Heuristic models have predicted both increases and decreases in parasite abundance in response to human disturbance, with empirical support for both. However, most studies focus on one or a few selected parasite species. Here, we assess the abundance of parasites of seven species of coral reef fishes collected from three fished and three unfished islands of the Line Islands archipelago in the central equatorial Pacific. Because we chose fish hosts that spanned different trophic levels, taxonomic groups, and body sizes, we were able to compare parasite responses across a broad cross section of the total parasite community in the presence and absence of fishing, a major human impact on marine ecosystems. We found that overall parasite species richness was substantially depressed on fished islands, but that the response of parasite abundance varied among parasite taxa: directly transmitted parasites were significantly more abundant on fished than on unfished islands, while the reverse was true for trophically transmitted parasites. This probably arises because trophically transmitted parasites require multiple host species, some of which are the top predators most sensitive to fishing impacts. The increase in directly transmitted parasites appeared to be due to fishing-driven compensatory increases in the abundance of their hosts. Together, these results provide support for the predictions of both heuristic models, and indicate that the direction of fishing's impact on parasite abundance is mediated by parasite traits, notably parasite transmission strategies.

  2. Soil biota suppress positive plant diversity effects on productivity at high but not low soil fertility

    NARCIS (Netherlands)

    Luo, Shan; Deyn, De Gerlinde B.; Jiang, B.; Yu, Shixiao

    2017-01-01

    Plant community productivity commonly increases with increasing plant diversity, which is explained by complementarity among plant species in resource utilization (complementarity effect), or by selection of particularly productive plant species in diverse plant communities (selection effect).

  3. The effects of diabetes and low blood sugar levels on driving behaviour : Comparison of diabetics and non-diabetics

    NARCIS (Netherlands)

    Martens, M.; Janssen, W.H.; Stork, A.

    2001-01-01

    Under contract with the University Medical Centre, Utrecht, TNO Human Factors has conducted research to investigate the effect of diabetes on driving behaviour. In a driving simulator experiment, patients with diabetes and non-diabetics were confronted with various trafßc situations. The subject

  4. Do Smooth Waters Run Deep? Alcohol Intoxication and the Effects of Water Consumption on Driving-Related Cognitions and Behavior

    NARCIS (Netherlands)

    Spaanjaars, N.L.; Spijkerman, R.; Engels, R.C.M.E.

    2011-01-01

    The present study tested the effect of the combined use of alcohol and water on driving-related cognitions and behavior. Seventy-four female students performed a driving simulator task after having consumed alcohol or a placebo. Additionally, half of the participants consumed 0.5 liter of water. It

  5. Simulated driving in obstructive sleep apnoea-hypopnoea : effects of oral appliances and continuous positive airway pressure

    NARCIS (Netherlands)

    Hoekema, Aarnoud; Stegenga, Boudewijn; Bakker, Marije; Brouwer, Wiebo H.; de Bont, Lambert G. M.; Wijkstra, Peter J.; van der Hoeven, Johannes H.

    Impaired simulated driving performance has been demonstrated in obstructive sleep apnoea-hypopnoea syndrome (OSAHS) patients. Although continuous positive airway pressure (CPAP) generally improves simulated driving performance, the effects of oral-appliance (OA) therapy are unknown. The aims of this

  6. Building effective working relationships across culturally and ethnically diverse communities.

    Science.gov (United States)

    Hosley, Cheryl A; Gensheimer, Linda; Yang, Mai

    2003-01-01

    Amherst H. Wilder Foundation's Social Adjustment Program for Southeast Asians is implementing two collaborative, best practice, mental health and substance abuse prevention service models in Minnesota. It faced several issues in effectively bridging multiple cultural groups, including building a diverse collaborative team, involving families and youth, reconciling cultural variation in meeting styles, and making best practice models culturally appropriate. Researchers and program staff used multiple strategies to address these challenges and build successful partnerships. Through shared goals, flexibility, and a willingness to explore and address challenges, collaboratives can promote stronger relationships across cultural communities and improve their service delivery systems.

  7. The effects of anthropometry and leg muscle power on drive and transition phase of acceleration

    DEFF Research Database (Denmark)

    Nikolaidis, Pantelis T.; Ingebrigtsen, Jørgen; Jeffreys, Ian

    2016-01-01

    Background: The aim of this study was to examine the effect of anthropometry and leg muscle power on accelerative ability and its phases (drive and transition). METHODS: Thirty-six soccer players (age 12.4±1.2 years, body mass 49.9±8.9 kg and height 154.2±10.3 cm) were tested twice, in the beginn......Background: The aim of this study was to examine the effect of anthropometry and leg muscle power on accelerative ability and its phases (drive and transition). METHODS: Thirty-six soccer players (age 12.4±1.2 years, body mass 49.9±8.9 kg and height 154.2±10.3 cm) were tested twice......, in the beginning and in the end of competitive season, for anthropometric characteristics, countermovement jump and 20-meter acceleration (split 0-10 meters and 10-20 meters, indices of drive and transition, respectively). The soccer players were grouped according to seasonal changes in 20-meter acceleration (δacc...

  8. Cross effects on electron-cyclotron and lower-hybrid current drive in tokamak plasmas

    International Nuclear Information System (INIS)

    Fidone, I.; Giruzzi, G.; Krivenski, V.; Mazzucato, E.; Ziebell, L.F.

    1986-11-01

    Electron cyclotron resonance current drive in a tokamak plasma in the presence of a lower hybrid tail is investigated using a 2D Fokker-Planck code. For an extraordinary mode at oblique propagation and down-shifted frequency it is shown that the efficiency of electron cyclotron current drive becomes, i) substantially greater than the corresponding efficiency of a Maxwellian plasma at the same bulk temperature, ii) equal or greater than that of the lower hybrid waves, iii) comparable with the efficiency of a Maxwellian plasma at much higher temperature. This enhancement results from a beneficial cross-effect of the two waves on the formation of the current carrying electron tail. (5 fig; 17 refs)

  9. Bioaugmentation of thiabendazole-contaminated soils from a wastewater disposal site: Factors driving the efficacy of this strategy and the diversity of the indigenous soil bacterial community.

    Science.gov (United States)

    Papadopoulou, Evangelia S; Genitsaris, Savvas; Omirou, Michalis; Perruchon, Chiara; Stamatopoulou, Anastasia; Ioannides, Ioannis; Karpouzas, Dimitrios G

    2018-02-01

    The application of the fungicide thiabendazole (TBZ) in fruit packaging plants (FPP) results in the production of effluents which are often disposed in adjacent field sites. These require remediation to prevent further environmental dispersal of TBZ. We assessed the bioaugmentation potential of a newly isolated TBZ-degrading bacterial consortium in a naturally contaminated soil (NCS) exhibiting a natural gradient of TBZ levels (12000, 400, 250 and 12 mg kg -1 ). The effect of aging on bioaugmentation efficacy was comparatively tested in a soil with similar physicochemical properties and soil microbiota, which was artificially, contaminated with the same TBZ levels (ACS). The impact of bioaugmentation and TBZ on the bacterial diversity in the NCS was explored via amplicon sequencing. Bioaugmentation effectively removed TBZ from both soils at levels up to 400 mg kg -1 but failed at the highest contamination level (12000 mg kg -1 ). Dissipation of TBZ in bioaugmented samples showed a concentration-dependent pattern, while aging of TBZ had a slight effect on bioaugmentation efficiency. Bioaugmentation had no impact on the soil bacterial diversity, in contrast to TBZ contamination. Soils from the hotspots of TBZ contamination (12000 mg kg -1 ) showed a drastically lower α-diversity driven by the dominance of β- and γ-proteobacteria at the expense of all other bacterial phyla, especially Actinobacteria. Overall, bioaugmentation with specialized microbial inocula could be an effective solution for the recovery of disposal sites contaminated with persistent chemicals like TBZ. Copyright © 2017 Elsevier Ltd. All rights reserved.

  10. Effects of age and the use of hands-free cellular phones on driving behavior and task performance.

    Science.gov (United States)

    Liu, Yung-Ching; Ou, Yang-Kun

    2011-12-01

    This study used a driving simulator to investigate the effect of using a Bluetooth hands-free cellular phone earpiece on the driving behavior of two age groups. Forty-eight participants (24 aged 20-26 and 24 aged 65-73) were examined to assess their performance on the following divided-attention tasks under 2 driving load conditions (high and low): (1) attempting to maintain the speed limit and (2) using a cellular phone while driving. The length of the call conversation (long vs. short) and the conversational content (complex vs. simple) were manipulated as within-subject independent variables. The driving behavior of the participants, their task reaction times and accuracy, and subjective ratings were collected as dependent variables. The results indicate that under low driving loads, short talk times, and simple conversational content, the driving behavior of the participants showed low variance in the vehicle's mean speed. In contrast, complex conversation had a significantly negative impact on driving behavior. Notably, under a low driving load, motorists' driving behaviors, measured in lateral acceleration, caused significantly smaller variance in complex conversations compared to no call and simple conversations. The use of a hands-free cellular phone affected the performance (acceleration, lane deviation, reaction time, and accuracy) of older drivers significantly more than younger drivers. While performing divided attention tasks, the accuracy of the older drivers was 66.3 percent and that of the younger drivers was 96.3 percent. Although this study did not find a clear impact of cellular phone use on the driving behavior of younger drivers, their divided-attention task reaction times and accuracy were better under no-call than calling conditions. This study indicates that the use of hands-free cellular phones could significantly affect the safety of driving among the older and present risks, although lesser, for younger drivers.

  11. The traffic climate in China: The mediating effect of traffic safety climate between personality and dangerous driving behavior.

    Science.gov (United States)

    Zhang, Qian; Ge, Yan; Qu, Weina; Zhang, Kan; Sun, Xianghong

    2018-04-01

    Traffic safety climate is defined as road users' attitudes and perceptions of traffic in a specific context at a given point in time. The current study aimed to validate the Chinese version of the Traffic Climate Scale (TCS) and to explore its relation to drivers' personality and dangerous driving behavior. A sample of 413 drivers completed the Big Five Inventory (BFI), the Chinese version of the TCS, the Dula Dangerous Driving Index (DDDI) and a demographic questionnaire. Exploratory factor analysis and confirmatory factor analysis were performed to confirm a three-factor (external affective demands, internal requirements and functionality) solution of the TCS. The reliability and validity of the Chinese version of TCS were verified. More importantly, the results showed that the effect of personality on dangerous driving behavior was mediated by traffic climate. Specifically, the functionality of the TCS mediated the effect of neuroticism on negative cognitive/emotional driving and drunk driving, while openness had an indirect impact on aggressive driving, risky driving and drunk driving based on the internal requirements of the TCS. Additionally, agreeableness had a negative direct impact on four factors of the DDDI, while neuroticism had a positive direct impact on negative cognitive/emotional driving, drunk driving and risky driving. In conclusion, the Chinese version of the TCS will be useful to evaluate drivers' attitudes towards and perceptions of the requirements of traffic environment in which they participate and will also be valuable for comparing traffic cultures and environments in different countries. Copyright © 2018 Elsevier Ltd. All rights reserved.

  12. The effects of practice with MP3 players on driving performance.

    Science.gov (United States)

    Chisholm, S L; Caird, J K; Lockhart, J

    2008-03-01

    This study examined the effects of repeated iPod interactions on driver performance to determine if performance decrements decreased with practice. Nineteen younger drivers (mean age=19.4, range 18-22) participated in a seven session study in the University of Calgary Driving Simulator (UCDS). Drivers encountered a number of critical events on the roadways while interacting with an iPod including a pedestrian entering the roadway, a vehicle pullout, and a lead vehicle braking. Measures of hazard response, vehicle control, eye movements, and secondary task performance were analyzed. Increases in perception response time (PRT) and collisions were found while drivers were performing the difficult iPod tasks, which involved finding a specific song within the song titles menu. Over the course of the six experimental sessions, driving performance improved in all conditions. Difficult iPod interactions significantly increased the amount of visual attention directed into the vehicle above that of the baseline condition. With practice, slowed responses to driving hazards while interacting with the iPod declined somewhat, but a decrement still remained relative to the baseline condition. The multivariate results suggest that access to difficult iPod tasks while vehicles are in motion should be curtailed.

  13. Experimental Investigation of the Effect of the Driving Voltage of an Electroadhesion Actuator.

    Science.gov (United States)

    Koh, Keng Huat; Sreekumar, M; Ponnambalam, S G

    2014-06-25

    This paper investigates the effect of driving voltage on the attachment force of an electroadhesion actuator, as the existing literature on the saturation of the adhesive force at a higher electric field is incomplete. A new type of electroadhesion actuator using normally available materials, such as aluminum foil, PVC tape and a silicone rubber sheet used for keyboard protection, has been developed with a simple layered structure that is capable of developing adhesive force consistently. The developed actuator is subjected to the experiment for the evaluation of various test surfaces; aluminum, brick, ceramic, concrete and glass. The driving high voltage is varied in steps to determine the characteristics of the output holding force. Results show a quadratic relation between F (adhesion force) and V (driving voltage) within the 2 kV range. After this range, the F - V responses consistently show a saturation trend at high electric fields. Next, the concept of the leakage current that can occur in the dielectric material and the corona discharge through air has been introduced. Results show that the voltage level, which corresponds to the beginning of the supply current, matches well with the beginning of the force saturation. With the confirmation of this hypothesis, a working model for electroadhesion actuation is proposed. Based on the experimental results, it is proposed that such a kind of actuator can be driven within a range of optimum high voltage to remain electrically efficient. This practice is recommended for the future design, development and characterization of electroadhesion actuators for robotic applications.

  14. Effect of rotor rectifier on motor performance in slip recovery drives

    Energy Technology Data Exchange (ETDEWEB)

    Al Zahawi, B.A.T.; Jones, B.L.; Drury, W.

    1987-01-01

    The static Kramer system, comprising a slip-ring induction motor and a slip energy recovery circuit, is one of the simplest and most efficient forms of ac variable-speed drive. It is sometimes used to upgrade drives which had originally been designed for fixed speed operation, often with substantial energy savings. In such cases, it is important to know how the inclusion of a rectifier in the slip energy recovery circuit affects motor performance. A satisfactory model for the motor-rectifier combination is also needed to provide a sound basis for assessing alternative forms of recovery systems which aim to overcome the principal shortcomings of the drive, namely the magnitude and variability of its reactive power. Despite its simplicity, the Kramer drive presents a formidable analytical challenge. Rigorous analysis is particularly difficult and there is a need for a simpler form of analysis when calculating ratings and steady-state performance. The approach taken in this paper uses a transformer-type model for the motor, and largely analytical expressions for predicting torque, stator power, stator reactive power and rectifier output voltage. Motor resistances, diode characteristics, and the several possible rectifier overlap modes are included. It is shown that the rectifier has an adverse effect on stator reactive power, power factor, and peak torque, particularly at speeds well below synchronous, requiring some derating of motors designed for resistance control and also requiring additional power factor correction. While the analysis does not cater to variations caused by harmonics at some speeds, it does provide a quick, accurate method of predicting performance over most sections of the operating range. 12 refs., 11 figs.

  15. Genetic diversity, phylogeographic structure and effect of selection ...

    Indian Academy of Sciences (India)

    Abdulhakeem B. Ajibike

    2017-12-11

    Dec 11, 2017 ... RESEARCH ARTICLE. Genetic diversity, phylogeographic ... chickens as genetic resources towards ensuring food security. Keywords. genetic diversity ... PCR product as template DNA, 3.2 pmol of primer and. 8 μL of Big Dye ...

  16. The effect of touch-key size on the usability of In-Vehicle Information Systems and driving safety during simulated driving.

    Science.gov (United States)

    Kim, Heejin; Kwon, Sunghyuk; Heo, Jiyoon; Lee, Hojin; Chung, Min K

    2014-05-01

    Investigating the effect of touch-key size on usability of In-Vehicle Information Systems (IVISs) is one of the most important research issues since it is closely related to safety issues besides its usability. This study investigated the effects of the touch-key size of IVISs with respect to safety issues (the standard deviation of lane position, the speed variation, the total glance time, the mean glance time, the mean time between glances, and the mean number of glances) and the usability of IVISs (the task completion time, error rate, subjective preference, and NASA-TLX) through a driving simulation. A total of 30 drivers participated in the task of entering 5-digit numbers with various touch-key sizes while performing simulated driving. The size of the touch-key was 7.5 mm, 12.5 mm, 17.5 mm, 22.5 mm and 27.5 mm, and the speed of driving was set to 0 km/h (stationary state), 50 km/h and 100 km/h. As a result, both the driving safety and the usability of the IVISs increased as the touch-key size increased up to a certain size (17.5 mm in this study), at which they reached asymptotes. We performed Fitts' law analysis of our data, and this revealed that the data from the dual task experiment did not follow Fitts' law. Copyright © 2013 Elsevier Ltd and The Ergonomics Society. All rights reserved.

  17. Harnessing demographic differences in organizations: What moderates the effects of workplace diversity?

    OpenAIRE

    Guillaume, YRF; Dawson, JF; Otaye-Ebede, L; Woods, SA; West, MA

    2015-01-01

    To account for the double-edged nature of demographic workplace diversity (i.e. relational demography, work group diversity, and organizational diversity) effects on social integration, performance and well-being related variables, research has moved away from simple main effect approaches and started examining variables that moderate these effects. While there is no shortage of primary studies of the conditions under which diversity leads to positive or negative outcomes, it remains unclear ...

  18. Sequential Dependencies in Driving

    Science.gov (United States)

    Doshi, Anup; Tran, Cuong; Wilder, Matthew H.; Mozer, Michael C.; Trivedi, Mohan M.

    2012-01-01

    The effect of recent experience on current behavior has been studied extensively in simple laboratory tasks. We explore the nature of sequential effects in the more naturalistic setting of automobile driving. Driving is a safety-critical task in which delayed response times may have severe consequences. Using a realistic driving simulator, we find…

  19. Het effect van begeleid rijden (2toDrive) op zelfgerapporteerde ongevallen en overtredingen : een vragenlijstonderzoek onder alle jonge automobilisten in Nederland.

    OpenAIRE

    Schagen, I.N.L.G. van Korving, H. & Craen, S. de

    2015-01-01

    The effect of accompanied driving (2toDrive) on self-reported crashes and violations : a questionnaire survey among all young drivers in the Netherlands. In 2011, a six-year accompanied driving pilot under the name of 2toDrive was launched in the Netherlands: young people can get their driving licence B before they are 18 years old, but until their 18th birthday they can only drive while accompanied by an experienced driver. This way they gain more and more varied experience before driving so...

  20. The effectiveness of a diversity awareness training programme

    Directory of Open Access Journals (Sweden)

    Colette Cavaleros

    2002-10-01

    Full Text Available The objective of this study was to assess the effectiveness of a diversity awareness training programme. A sample of 382 employees from four different departments within a large accounting firm was used to form the groups of a simulated Solomon four-group design. The impact of a two-day workshop on diversity awareness was assessed using a 68-item questionnaire designed to measure awareness of self, impact of differences, performance management, career development, teamwork, work-family needs, participation, organisational culture, relationship building, and general satisfaction with the organisation. Opsomming Die doel met hierdie studie was om die effektiwiteit van ‘n bewustheid-van-diversiteit opleidingsprogram te bepaal. Werknemers uit vier departemente van ‘n groot ouditeursfirma het die groepe van ‘n gesimuleerde Solomon viergroepontwerp gevorm (N = 382. Die impak van ‘n tweedagwerkwinkel oor bewustheid-van-diversiteit is bepaal met ‘n 68-item vraelys wat ontwikkel is om bewustheid van die self, impak van verskille, prestasiebestuur, loopbaanontwikkeling, spanwerk, werk-gesinsbehoeftes, deelname, organisasiekultuur, ontwikkeling van verhoudings, en algemene tevredenheid met die organisasie te meet.

  1. Effects of two doses of alcohol on simulator driving performance in adults with attention-deficit/hyperactivity disorder.

    Science.gov (United States)

    Barkley, Russell A; Murphy, Kevin R; O'Connell, Trisha; Anderson, Deborah; Connor, Daniel F

    2006-01-01

    Prior studies have documented greater impairments in driving performance and greater alcohol consumption among adults with attention-deficit/hyperactivity disorder (ADHD). This study examined whether alcohol consumption produces a differentially greater impairment in driving among adults with ADHD in comparison to a community control group. The present study compared 50 adults with ADHD (mean age 33 years) and 40 control adults (mean age 29 years) on the effects of 2 single, acute doses of alcohol (0.04 and 0.08 blood alcohol concentration) and a placebo on their driving performance. The authors used a virtual reality driving simulator, examiner and self-ratings of simulator performance, and a continuous performance test (CPT) to evaluate attention and inhibition. Approximately half of the adults in each group were randomized to either the low or high dose alcohol treatment arms. Alcohol consumption produced a greater impact on the CPT inattention measures of the ADHD than the control group. Similar results were obtained for the behavioral observations taken during the operation of the driving simulator. Driving simulator scores, however, showed mainly a deleterious effect of alcohol on all participants but no differentially greater effect on the ADHD group. The present results demonstrated that alcohol may have a greater detrimental effect on some aspects of driving performance in ADHD than control adults.

  2. Opposing effects of floral visitors and soil conditions on the determinants of competitive outcomes maintain species diversity in heterogeneous landscapes.

    Science.gov (United States)

    Lanuza, Jose B; Bartomeus, Ignasi; Godoy, Oscar

    2018-06-01

    Theory argues that both soil conditions and aboveground trophic interactions have equivalent potential to limit or promote plant diversity. However, it remains unexplored how they jointly modify the niche differences stabilising species coexistence and the average fitness differences driving competitive dominance. We conducted a field study in Mediterranean annual grasslands to parameterise population models of six competing plant species. Spatially explicit floral visitor assemblages and soil salinity variation were characterised for each species. Both floral visitors and soil salinity modified species population dynamics via direct changes in seed production and indirect changes in competitive responses. Although the magnitude and sign of these changes were species-specific, floral visitors promoted coexistence at neighbourhood scales, while soil salinity did so over larger scales by changing the superior competitors' identity. Our results show how below and aboveground interactions maintain diversity in heterogeneous landscapes through their opposing effects on the determinants of competitive outcomes. © 2018 John Wiley & Sons Ltd/CNRS.

  3. Drive Stands

    Data.gov (United States)

    Federal Laboratory Consortium — The Electrical Systems Laboratory (ESL)houses numerous electrically driven drive stands. A drive stand consists of an electric motor driving a gearbox and a mounting...

  4. A simulator study of the combined effects of alcohol and marihuana on driving behavior--phase II

    Science.gov (United States)

    1983-02-01

    Author's abstract: The study described in this report investigated the effects of alcohol and marihuana, alone and in combination, on driver performance and behavior in a fully interactive driving simulator. The simulator provided the driver a comple...

  5. The Effectiveness of Drinking and Driving Policies for Different Alcohol-Related Fatalities: A Quantile Regression Analysis

    Directory of Open Access Journals (Sweden)

    Koyin Chang

    2013-09-01

    Full Text Available To understand the impact of drinking and driving laws on drinking and driving fatality rates, this study explored the different effects these laws have on areas with varying severity rates for drinking and driving. Unlike previous studies, this study employed quantile regression analysis. Empirical results showed that policies based on local conditions must be used to effectively reduce drinking and driving fatality rates; that is, different measures should be adopted to target the specific conditions in various regions. For areas with low fatality rates (low quantiles, people’s habits and attitudes toward alcohol should be emphasized instead of transportation safety laws because “preemptive regulations” are more effective. For areas with high fatality rates (or high quantiles, “ex-post regulations” are more effective, and impact these areas approximately 0.01% to 0.05% more than they do areas with low fatality rates.

  6. Finite Larmor radius effects on Alfven wave current drive in low-aspect ratio tokamaks

    International Nuclear Information System (INIS)

    Komoshvili, K.; Cuperman, S.; Bruma, C.

    1998-01-01

    Alfven wave current drive (AWCD) in low-aspect ratio (A≡R/a=1/ε > or approx. 1) tokamaks (LARTs) is studied numerically. For this, the full-wave equation (E parallel ≠0) with a Vlasov-based dielectric tensor is solved by relaxation techniques, subject to appropriate boundary conditions at the plasma centre and at the plasma-vacuum interface, as well as the concentric antenna current sheet and at the external metallic wall. A systematic investigation of the physical characteristics of the AWCD generated in LARTs when kinetic effects are considered is carried out and illustrative results are presented and discussed. (author)

  7. The effects of age and workload on 3D spatial attention in dual-task driving.

    Science.gov (United States)

    Pierce, Russell S; Andersen, George J

    2014-06-01

    In the present study we assessed whether the limits in visual-spatial attention associated with aging affect the spatial extent of attention in depth during driving performance. Drivers in the present study performed a car-following and light-detection task. To assess the extent of visual-spatial attention, we compared reaction times and accuracy to light change targets that varied in horizontal position and depth location. In addition, because workload has been identified as a factor that can change the horizontal and vertical extent of attention, we tested whether variability of the lead car speed influenced the extent of spatial attention for younger or older drivers. For younger drivers, reaction time (RT) to light-change targets varied as a function of distance and horizontal position. For older drivers RT varied only as a function of distance. There was a distance by horizontal position interaction for younger drivers but not for older drivers. Specifically, there was no effect of horizontal position at any given level of depth for older drivers. However, for younger drivers there was an effect of horizontal position for targets further in depth but not for targets nearer in depth. With regards to workload, we found no statistically reliable evidence that variability of the lead car speed had an effect on the spatial extent of attention for younger or older drivers. In a control experiment, we examined the effects of depth on light detection when the projected size and position of the targets was constant. Consistent with our previous results, we found that drivers' reaction time to light-change targets varied as a function of distance even when 2D position and size were controlled. Given that depth is an important dimension in driving performance, an important issue for assessing driving safety is to consider the limits of attention in the depth dimension. Therefore, we suggest that future research should consider the importance of depth as a dimension of

  8. Mental workload while driving: effects on visual search, discrimination, and decision making.

    Science.gov (United States)

    Recarte, Miguel A; Nunes, Luis M

    2003-06-01

    The effects of mental workload on visual search and decision making were studied in real traffic conditions with 12 participants who drove an instrumented car. Mental workload was manipulated by having participants perform several mental tasks while driving. A simultaneous visual-detection and discrimination test was used as performance criteria. Mental tasks produced spatial gaze concentration and visual-detection impairment, although no tunnel vision occurred. According to ocular behavior analysis, this impairment was due to late detection and poor identification more than to response selection. Verbal acquisition tasks were innocuous compared with production tasks, and complex conversations, whether by phone or with a passenger, are dangerous for road safety.

  9. The effect of aging upon CE and B ampersand W control rod drives

    International Nuclear Information System (INIS)

    Grove, E.; Gunther, W.

    1991-01-01

    The effect of aging upon the Babcock ampersand Wilcox (B ampersand W) and Combustion Engineering (CE) Control Rod Drive (CRD) systems has been evaluated as part of the USNRC Nuclear Plant Aging Research (NPAR) program. Operating experience data for the 1980--1990 time period was reviewed to identify predominant failure modes, causes, and effects. These results, in conjunction with an assessment of component materials and operating environment, conclude that both systems are susceptible to age degradation. System failures have resulted in significant plant effects, including power reductions, plant shutdowns, scrams, and Engineered Safety Feature (ESF) actuation. Current industry inspection and maintenance practices were assessed. Some of these practices effectively address aging, while others do not

  10. Effects of plant species identity, diversity and soil fertility on biodegradation of phenanthrene in soil

    Energy Technology Data Exchange (ETDEWEB)

    Oyelami, Ayodeji O; Okere, Uchechukwu V; Orwin, Kate H; De Deyn, Gerlinde B; Jones, Kevin C [Lancaster Environment Centre, Lancaster University, Lancaster LA1 4YQ (United Kingdom); Semple, Kirk T., E-mail: k.semple@lancaster.ac.uk [Lancaster Environment Centre, Lancaster University, Lancaster LA1 4YQ (United Kingdom)

    2013-02-15

    The work presented in this paper investigated the effects of plant species composition, species diversity and soil fertility on biodegradation of {sup 14}C-phenanthrene in soil. The two soils used were of contrasting fertility, taken from long term unfertilised and fertilised grassland, showing differences in total nitrogen content (%N). Plant communities consisted of six different plant species: two grasses, two forbs, and two legume species, and ranged in species richness from 1 to 6. The degradation of {sup 14}C-phenanthrene was evaluated by measuring indigenous catabolic activity following the addition of the contaminant to soil using respirometry. Soil fertility was a driving factor in all aspects of {sup 14}C-phenanthrene degradation; lag phase, maximum rates and total extents of {sup 14}C-phenanthrene mineralisation were higher in improved soils compared to unimproved soils. Plant identity had a significant effect on the lag phase and extents of mineralisation. Soil fertility was the major influence also on abundance of microbial communities. - Highlights: Black-Right-Pointing-Pointer Two grassland soils of contrasting fertility showing differences in total nitrogen content (%N) were used in this study. Black-Right-Pointing-Pointer The effects of individual plant species and plant diversity on mineralisation of {sup 14}C-phenanthrene in soil were investigated. Black-Right-Pointing-Pointer Soil fertility was the major influence on mineralisation of {sup 14}C-phenanthrene, and abundance of microbial community. Black-Right-Pointing-Pointer The presence of a specific plant plays a role in the extent of mineralisation of phenanthrene in soil. - Soil management was the main driver for the mineralisation of {sup 14}C-phenanthrene in soil.

  11. Effects of plant species identity, diversity and soil fertility on biodegradation of phenanthrene in soil

    International Nuclear Information System (INIS)

    Oyelami, Ayodeji O.; Okere, Uchechukwu V.; Orwin, Kate H.; De Deyn, Gerlinde B.; Jones, Kevin C.; Semple, Kirk T.

    2013-01-01

    The work presented in this paper investigated the effects of plant species composition, species diversity and soil fertility on biodegradation of 14 C-phenanthrene in soil. The two soils used were of contrasting fertility, taken from long term unfertilised and fertilised grassland, showing differences in total nitrogen content (%N). Plant communities consisted of six different plant species: two grasses, two forbs, and two legume species, and ranged in species richness from 1 to 6. The degradation of 14 C-phenanthrene was evaluated by measuring indigenous catabolic activity following the addition of the contaminant to soil using respirometry. Soil fertility was a driving factor in all aspects of 14 C-phenanthrene degradation; lag phase, maximum rates and total extents of 14 C-phenanthrene mineralisation were higher in improved soils compared to unimproved soils. Plant identity had a significant effect on the lag phase and extents of mineralisation. Soil fertility was the major influence also on abundance of microbial communities. - Highlights: ► Two grassland soils of contrasting fertility showing differences in total nitrogen content (%N) were used in this study. ► The effects of individual plant species and plant diversity on mineralisation of 14 C-phenanthrene in soil were investigated. ► Soil fertility was the major influence on mineralisation of 14 C-phenanthrene, and abundance of microbial community. ► The presence of a specific plant plays a role in the extent of mineralisation of phenanthrene in soil. - Soil management was the main driver for the mineralisation of 14 C-phenanthrene in soil.

  12. Effects of alcohol (BAC 0.5‰) and ecstasy (MDMA 100 mg) on simulated driving performance and traffic safety.

    Science.gov (United States)

    Veldstra, Janet L; Brookhuis, Karel A; de Waard, Dick; Molmans, Barbara H W; Verstraete, Alain G; Skopp, Gisela; Jantos, Ricarda

    2012-08-01

    An increasing number of fatal road-accidents have been reported in which ecstasy was found in the blood of drivers. Although, ecstasy is frequently found to have been used in combination with alcohol, studies on the acute effects of ecstasy co-administered with alcohol on driving performance are relatively rare. The present study was designed to establish the extent of driver impairment as a consequence of ecstasy or combined ecstasy and alcohol use as compared to driving under the influence of 0.3‰, 0.5‰ and 0.8‰ alcohol. Furthermore, subjective performance was also assessed. Alcohol and ecstasy mainly influenced automated driving performance such as lateral and speed control. However, small to no effects of the substances were found on more complex driving behaviour. Overall, variance within the different driving measures was high especially when participants were treated with 3.4-methylenedioxy-methamphetamine (MDMA) and alcohol. Furthermore, equivalence testing showed that combined use may lead to impaired driving for some, but not all, drivers. Participants rated their own performance to be slightly worse than normal in both studies. Since driving was actually seriously deteriorated, this was a falsely positive assessment of their condition. The dissociation between subjective perceptions and objective performance decrements are important notions for traffic safety since this may affect a driver's judgement of whether or not it is safe to drive. For example, an intoxicated individual might decide to drive because the feelings of alertness caused by MDMA cloud the impairing effects of other drugs such as alcohol, thereby creating a potentially serious risk for traffic safety.

  13. Effects of prolonged wakefulness combined with alcohol and hands-free cell phone divided attention tasks on simulated driving.

    Science.gov (United States)

    Iudice, A; Bonanni, E; Gelli, A; Frittelli, C; Iudice, G; Cignoni, F; Ghicopulos, I; Murri, L

    2005-03-01

    Simulated driving ability was assessed following administration of alcohol, at an estimated blood level of 0.05%, and combined prolonged wakefulness, while participants were undertaking divided attention tasks over a hands-free mobile phone. Divided attention tasks were structured to provide a sustained cognitive workload to the subjects. Twenty three young healthy individuals drove 10 km simulated driving under four conditions in a counterbalanced, within-subject design: alcohol, alcohol and 19 h wakefulness, alcohol and 24 h wakefulness, and while sober. Study measures were: simulated driving, self-reported sleepiness, critical flicker fusion threshold (CFFT), Stroop word-colour interference test (Stroop) and simple visual reaction times (SVRT). As expected, subjective sleepiness was highly correlated with both sleep restriction and alcohol consumption. The combination of alcohol and 24 h sustained wakefulness produced the highest driving impairment, significantly beyond the alcohol effect itself. Concurrent alcohol and 19 h wakefulness significantly affected only driving time-to-collision. No significant changes of study measures occurred following alcohol intake in unrestricted sleep conditions. CFFT, SVRT and Stroop results showed a similar trend in the four study conditions. Thus apparently 'safe' blood alcohol levels in combination with prolonged wakefulness resulted in significant driving impairments. In normal sleep conditions alcohol effects on driving were partially counteracted by the concomitant hands-free phone based psychometric tasks. 2005 John Wiley & Sons, Ltd.

  14. Predicting plant diversity patterns in Madagascar: understanding the effects of climate and land cover change in a biodiversity hotspot.

    Directory of Open Access Journals (Sweden)

    Kerry A Brown

    Full Text Available Climate and land cover change are driving a major reorganization of terrestrial biotic communities in tropical ecosystems. In an effort to understand how biodiversity patterns in the tropics will respond to individual and combined effects of these two drivers of environmental change, we use species distribution models (SDMs calibrated for recent climate and land cover variables and projected to future scenarios to predict changes in diversity patterns in Madagascar. We collected occurrence records for 828 plant genera and 2186 plant species. We developed three scenarios, (i.e., climate only, land cover only and combined climate-land cover based on recent and future climate and land cover variables. We used this modelling framework to investigate how the impacts of changes to climate and land cover influenced biodiversity across ecoregions and elevation bands. There were large-scale climate- and land cover-driven changes in plant biodiversity across Madagascar, including both losses and gains in diversity. The sharpest declines in biodiversity were projected for the eastern escarpment and high elevation ecosystems. Sharp declines in diversity were driven by the combined climate-land cover scenarios; however, there were subtle, region-specific differences in model outputs for each scenario, where certain regions experienced relatively higher species loss under climate or land cover only models. We strongly caution that predicted future gains in plant diversity will depend on the development and maintenance of dispersal pathways that connect current and future suitable habitats. The forecast for Madagascar's plant diversity in the face of future environmental change is worrying: regional diversity will continue to decrease in response to the combined effects of climate and land cover change, with habitats such as ericoid thickets and eastern lowland and sub-humid forests particularly vulnerable into the future.

  15. Antihistamines and driving safety.

    Science.gov (United States)

    O'Hanlon, J F

    1988-10-27

    The results of two placebo-controlled driving performance studies confirm laboratory data showing that the nonsedating antihistamine terfenadine does not influence the driving performance of users. The amplitude of vehicle weaving calculated for drivers who received this agent did not differ from control values. Neither terfenadine nor loratadine, another nonsedating antihistamine, potentiated the adverse effects of alcohol on driving performance.

  16. The effects of an exercise program on several abilities associated with driving performance in older adults.

    Science.gov (United States)

    Marmeleira, José F; Godinho, Mário B; Fernandes, Orlando M

    2009-01-01

    The purpose of this study was to investigate the effects of participation in an exercise program on several abilities associated with driving performance in older adults. Thirty-two subjects were randomly assigned to either an exercise group (60-81 years, n=16) or a control group (60-82 years, n=16). The exercise program was planned to stress perceptive, cognitive, and physical abilities. It lasted 12 weeks with a periodicity of three sessions of 60 min per week. Assessments were conducted before and after the intervention on behavioral speed (in single- and dual-task conditions), visual attention, psychomotor performance, speed perception (time-to-contact), and executive functioning. Significant positive effects were found at 12-week follow-up resulting from participation in the exercise program. Behavioral speed improvements were found in reaction time, movement time, and response time (both in single- and dual-task conditions); visual attention improvements took place in speed processing and divided attention; psychomotor performance improvements occurred in lower limb mobility. These results showed that exercise is capable of enhancing several abilities relevant for driving performance and safety in older adults and, therefore, should be promoted.

  17. Using Floating Car Data to Analyse the Effects of ITS Measures and Eco-Driving

    Directory of Open Access Journals (Sweden)

    Alvaro Garcia-Castro

    2014-11-01

    Full Text Available The road transportation sector is responsible for around 25% of total man-made CO2 emissions worldwide. Considerable efforts are therefore underway to reduce these emissions using several approaches, including improved vehicle technologies, traffic management and changing driving behaviour. Detailed traffic and emissions models are used extensively to assess the potential effects of these measures. However, if the input and calibration data are not sufficiently detailed there is an inherent risk that the results may be inaccurate. This article presents the use of Floating Car Data to derive useful speed and acceleration values in the process of traffic model calibration as a means of ensuring more accurate results when simulating the effects of particular measures. The data acquired includes instantaneous GPS coordinates to track and select the itineraries, and speed and engine performance extracted directly from the on-board diagnostics system. Once the data is processed, the variations in several calibration parameters can be analyzed by comparing the base case model with the measure application scenarios. Depending on the measure, the results show changes of up to 6.4% in maximum speed values, and reductions of nearly 15% in acceleration and braking levels, especially when eco-driving is applied.

  18. Driving Simulator Study of Effect of Inside Shoulder on Vehicle Operation

    Directory of Open Access Journals (Sweden)

    Han Ding

    2015-02-01

    Full Text Available According to the Chinese Design Specification for Highway Alignment (JTG D20-2006, eight-lane expressways should be paved with an inside shoulder of 2.5 m; however, this regulation is rarely obeyed in engineering practice. On the basis of driving simulator experiment, this research examined the impacts of inside shoulder on vehicle operation with and without the speed limitation. A virtual scenario, consisting of five expressways with different inside shoulder widths, was created and displayed in driving simulator, and vehicle operational data—speed and lane position—were recorded. Authors used analysis of variance (ANOVA and contrast analysis to examine whether inside shoulder width had statistically significant effects on travel speed and lane position. Analytical results indicated that there is a kind of quadratic relationship between inside shoulder width and driver's speed choice, while driver's speed choice is not significantly affected by inside shoulder width. What is more, inside shoulder width has statistically significant effects on vehicle's lane positions, and vehicle's lane position is negatively correlated to inside shoulder width. Specifically, the vehicle can be maintained at the center of lane when the inside shoulder width is 2.5 m.

  19. A systematic review: effectiveness of mass media campaigns for reducing alcohol-impaired driving and alcohol-related crashes.

    Science.gov (United States)

    Yadav, Rajendra-Prasad; Kobayashi, Miwako

    2015-09-04

    Mass media campaigns have long been used as a tool for promoting public health. In the past decade, the growth of social media has allowed more diverse options for mass media campaigns. This systematic review was conducted to assess newer evidence from quantitative studies on the effectiveness of mass media campaigns for reducing alcohol-impaired driving (AID) and alcohol-related crashes, particularly after the paper that Elder et al. published in 2004. This review focused on English language studies that evaluated the effect of mass media campaigns for reducing AID and alcohol-related crashes, with or without enforcement efforts. A systematic search was conducted for studies published between January 1, 2002 and December 31, 2013. Studies from the review by Elder et al. were added as well. A total of 19 studies met the inclusion criteria for the systematic review, including three studies from the review by Elder et al. Nine of them had concomitant enforcement measures and did not evaluate the impact of media campaigns independently. Studies that evaluated the impact of mass media independently showed reduction more consistently (median -15.1%, range -28.8 to 0%), whereas results of studies that had concomitant enforcement activities were more variable (median -8.6%, range -36.4 to +14.6%). Summary effects calculated from seven studies showed no evidence of media campaigns reducing the risk of alcohol-related injuries or fatalities (RR 1.00, 95% CI = 0.94 to 1.06). Despite additional decade of evidence, reviewed studies were heterogeneous in their approaches; therefore, we could not conclude that media campaigns reduced the risk of alcohol-related injuries or crashes. More studies are needed, including studies evaluating newly emerging media and cost-effectiveness of media campaigns.

  20. Effects of racing games on risky driving behaviour, and the significance of personality and physiological data.

    Science.gov (United States)

    Deng, Mingming; Chan, Alan H S; Wu, Feng; Wang, Jun

    2015-08-01

    Racing games have emerged as top-selling products in the video and computer game industry. The effect of playing racing games on the inclination of gamers to take risks has been investigated. Two experiments were conducted. In experiment 1, the impact of personality traits on the effects of playing racing games on risk-taking inclination was examined. The Vienna Test System, which includes the Eysenck Personality Profile Test and the Vienna Risk-Taking Test, was used to measure risk-taking inclination and risk-taking while driving. Experiment 2 was designed and conducted to analyse the effects of different intensity levels of car racing games on risk-taking inclination, and to study the relationship between physiological data and risk-taking inclination. Physiological data on skin conductance, heart rate and blood pressure were measured with the NeuroDyne System. Participants playing a racing game were more inclined to take risks in critical road traffic situations than those playing a neutral game. The adventurousness dimension of the Eysenck Personality Profile Test correlated significantly positively with risk-taking inclination. More importantly, the effect of the intensity level of a racing game on risk-taking inclination was significant. The higher the intensity level of the racing game, the higher the risk-taking inclination while driving. The effect of intensity level of the racing game on skin conductance was significantly positive. Skin conductance correlated significantly positively with risk-taking inclination. The effect of playing racing games on risk-taking inclination is linked to personality and physiological data. Some recommendations are proposed as a result of this study for racing game management. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

  1. Experimental Investigation of the Effect of the Driving Voltage of an Electroadhesion Actuator

    Directory of Open Access Journals (Sweden)

    Keng Huat Koh

    2014-06-01

    Full Text Available This paper investigates the effect of driving voltage on the attachment force of an electroadhesion actuator, as the existing literature on the saturation of the adhesive force at a higher electric field is incomplete. A new type of electroadhesion actuator using normally available materials, such as aluminum foil, PVC tape and a silicone rubber sheet used for keyboard protection, has been developed with a simple layered structure that is capable of developing adhesive force consistently. The developed actuator is subjected to the experiment for the evaluation of various test surfaces; aluminum, brick, ceramic, concrete and glass. The driving high voltage is varied in steps to determine the characteristics of the output holding force. Results show a quadratic relation between F (adhesion force and V (driving voltage within the 2 kV range. After this range, the F-V responses consistently show a saturation trend at high electric fields. Next, the concept of the leakage current that can occur in the dielectric material and the corona discharge through air has been introduced. Results show that the voltage level, which corresponds to the beginning of the supply current, matches well with the beginning of the force saturation. With the confirmation of this hypothesis, a working model for electroadhesion actuation is proposed. Based on the experimental results, it is proposed that such a kind of actuator can be driven within a range of optimum high voltage to remain electrically efficient. This practice is recommended for the future design, development and characterization of electroadhesion actuators for robotic applications.

  2. Soil chemistry in lithologically diverse datasets: the quartz dilution effect

    Science.gov (United States)

    Bern, Carleton R.

    2009-01-01

    National- and continental-scale soil geochemical datasets are likely to move our understanding of broad soil geochemistry patterns forward significantly. Patterns of chemistry and mineralogy delineated from these datasets are strongly influenced by the composition of the soil parent material, which itself is largely a function of lithology and particle size sorting. Such controls present a challenge by obscuring subtler patterns arising from subsequent pedogenic processes. Here the effect of quartz concentration is examined in moist-climate soils from a pilot dataset of the North American Soil Geochemical Landscapes Project. Due to variable and high quartz contents (6.2–81.7 wt.%), and its residual and inert nature in soil, quartz is demonstrated to influence broad patterns in soil chemistry. A dilution effect is observed whereby concentrations of various elements are significantly and strongly negatively correlated with quartz. Quartz content drives artificial positive correlations between concentrations of some elements and obscures negative correlations between others. Unadjusted soil data show the highly mobile base cations Ca, Mg, and Na to be often strongly positively correlated with intermediately mobile Al or Fe, and generally uncorrelated with the relatively immobile high-field-strength elements (HFS) Ti and Nb. Both patterns are contrary to broad expectations for soils being weathered and leached. After transforming bulk soil chemistry to a quartz-free basis, the base cations are generally uncorrelated with Al and Fe, and negative correlations generally emerge with the HFS elements. Quartz-free element data may be a useful tool for elucidating patterns of weathering or parent-material chemistry in large soil datasets.

  3. Dementia & Driving

    Science.gov (United States)

    ... have to give up driving. Many people associate driving with self-reliance and freedom; the loss of driving privileges ... familiar roads and avoid long distances. Avoid heavy traffic and heavily traveled roads. Avoid driving at night and in bad weather. Reduce the ...

  4. The effect of family climate on risky driving of young novices: the moderating role of attitude and locus of control.

    Science.gov (United States)

    Carpentier, Aline; Brijs, Kris; Declercq, Katrien; Brijs, Tom; Daniels, Stijn; Wets, Geert

    2014-12-01

    The aim of the study was to examine the relative importance of young novice drivers' family climate on their driving behavior. A sample of young novice drivers (N=171) between the age of 17 and 24, who held their permanent (or temporary) driver's license for no longer than one year, participated. The questionnaire included items related to the participants' family climate, 3 socio-cognitive determinants (i.e., attitude, locus of control and social norm), and risky driving behaviors. We expected both family climate and the socio-cognitive determinants to exert a direct effect on risky driving. Furthermore we hypothesized that the socio-cognitive determinants would moderate the impact of family climate on risky driving. The results showed that the effect of family climate on risky driving only originated from one single factor (i.e., noncommitment). Besides that, the results confirmed the importance of the three socio-cognitive determinants to the degree that attitude, locus of control, and social norm significantly predicted the self-reported risky driving. In line of what we hypothesized, attitude moderated the relationship between noncommitment and risky driving. Lastly, we found an unexpected three-way interaction which indicated that locus of control moderated the relation between noncommitment and risky driving only when young drivers' attitude was risk-supportive. We recommend scholars and practitioners to take into account the interaction between external sources of influence (such as an individual's family climate) and more personally oriented dispositions (such as an individual's attitude, social norm and locus of control) when trying to explain and change young novices' risky driving. Copyright © 2014 Elsevier Ltd. All rights reserved.

  5. The Effect of High and Low Antiepileptic Drug Dosage on Simulated Driving Performance in Person's with Seizures: A Pilot Study

    Directory of Open Access Journals (Sweden)

    Alexander M. Crizzle

    2015-10-01

    Full Text Available Background: Prior studies examining driving performance have not examined the effects of antiepileptic drugs (AED’s or their dosages in persons with epilepsy. AED’s are the primary form of treatment to control seizures, but they are shown to affect cognition, attention, and vision, all which may impair driving. The purpose of this study was to describe the characteristics of high and low AED dosages on simulated driving performance in persons with seizures. Method: Patients (N = 11; mean age 42.1 ± 6.3; 55% female; 100% Caucasian were recruited from the Epilepsy Monitoring Unit and had their driving assessed on a simulator. Results: No differences emerged in total or specific types of driving errors between high and low AED dosages. However, high AED drug dosage was significantly associated with errors of lane maintenance (r = .67, p < .05 and gap acceptance (r = .66, p < .05. The findings suggest that higher AED dosages may adversely affect driving performance, irrespective of having a diagnosis of epilepsy, conversion disorder, or other medical conditions. Conclusion: Future studies with larger samples are required to examine whether AED dosage or seizure focus alone can impair driving performance in persons with and without seizures.

  6. Diverse Effects of Cyclosporine on Hepatitis C Virus Strain Replication

    Science.gov (United States)

    Ishii, Naoto; Watashi, Koichi; Hishiki, Takayuki; Goto, Kaku; Inoue, Daisuke; Hijikata, Makoto; Wakita, Takaji; Kato, Nobuyuki; Shimotohno, Kunitada

    2006-01-01

    Recently, a production system for infectious particles of hepatitis C virus (HCV) utilizing the genotype 2a JFH1 strain has been developed. This strain has a high capacity for replication in the cells. Cyclosporine (CsA) has a suppressive effect on HCV replication. In this report, we characterize the anti-HCV effect of CsA. We observe that the presence of viral structural proteins does not influence the anti-HCV activity of CsA. Among HCV strains, the replication of genotype 1b replicons was strongly suppressed by treatment with CsA. In contrast, JFH1 replication was less sensitive to CsA and its analog, NIM811. Replication of JFH1 did not require the cellular replication cofactor, cyclophilin B (CyPB). CyPB stimulated the RNA binding activity of NS5B in the genotype 1b replicon but not the genotype 2a JFH1 strain. These findings provide an insight into the mechanisms of diversity governing virus-cell interactions and in the sensitivity of these strains to antiviral agents. PMID:16611911

  7. THE EFFECTS OF THE ORGANIZATIONAL CULTURE ON DIVERSITY

    Directory of Open Access Journals (Sweden)

    Hakan Sezerel

    2016-12-01

    Full Text Available The success of diversity management practices relies on the combination of a series of variables properly. The relevant literature suggests that diversity management is highly depended on an adequate organizational culture. Thus, a research model that proposes that organizational culture has impact on diversity management perceptions of employees. There are two data sets in this research. The independent variable of the research is organizational culture and the dependent variable of the research is the level of diversity management perceptions. The research is adopted in quantitative method and the data collected via questionnaires. This research which is conducted in a hotel chain finds that the mission dimension of organizational culture impacts all three levels of diversity management.

  8. Effect of Asymmetric Layout of IGBT Modules on Reliability of Power Inverters in Motor Drive System

    DEFF Research Database (Denmark)

    Choi, Uimin; Vernica, Ionut; Blaabjerg, Frede

    2018-01-01

    of inverters are limited by the most stressed devices. However, generally common data is provided for all devices and this may cause improper design of the inverters in terms of power rating and lifetime. In this paper, the effect of an asymmetric layout of IGBT modules on the reliability of power inverters......An IGBT module has typically multiple power devices for some technical and cost advantages. This kind of configurations could have an asymmetric layout, which may lead to different thermal loadings and thereby lifetime difference of the power devices. Therefore, both the power rating and lifetime...... is studied based on a 3-phase motor drive application with a 600 V, 30 A, 3-phase transfer molded IGBT module. The thermal impedances of 6 IGBTs are investigated and its effect on the thermal loadings of power devices is studied under the given mission profile. Finally, their lifetimes are estimated...

  9. Evaluation of Effects of Warning Sign Position on Driving Behavior in Horizontal Sharp Curves

    Directory of Open Access Journals (Sweden)

    Xiao-hua Zhao

    2015-02-01

    Full Text Available In present time, the guidelines on warning sign position in the China National Standard lack detailed and standard regulations of placing warning signs on sharp curves, which may cause road safety problems. Therefore, this paper briefly discussed how to optimize the position of a warning sign on a sharp curve through a driving simulator experiment. This study concluded that a warning sign placed at different positions prior to a sharp curve will have different influence ranges for drivers approaching and negotiating the curve. Meanwhile, different positions of a warning sign imposed different effect obviously on the adjustment of vehicle's lane position on sharp curves with the same radius, especially at the midpoint of a sharp curve. The evaluation results of five positions (0 m, 50 m, 100 m, 200 m, and 400 m in advance showed that only when the warning signs were placed 100 m or 200 m prior to sharp curves, can they achieve positive influence on driving behavior. On this basis, the authors look forward to providing rationalization proposals in selecting the best position of a warning sign on a sharp curve for the engineering implementation and national standard.

  10. Effectiveness of social norms media marketing in reducing drinking and driving: A statewide campaign.

    Science.gov (United States)

    Perkins, H Wesley; Linkenbach, Jeffrey W; Lewis, Melissa A; Neighbors, Clayton

    2010-10-01

    This research evaluated the efficacy of a high-intensity social norms media marketing campaign aimed at correcting normative misperceptions and reducing the prevalence of drinking and driving among 21-to-34-year-olds in Montana. A quasi-experimental design was used, such that regions of Montana were assigned to one of three experimental groups: social norms media marketing campaign, buffer, and control. Four random samples of Montanans between the ages of 21 and 34 were assessed at four time points over 18 months via phone surveys. Findings suggest that the social norms media campaign was successful at exposing the targeted population to social norms messages in the counties within the intervention region. Moreover, results demonstrate the campaign reduced normative misperceptions, increased use of designated drivers, and decreased drinking and driving among those young adults in counties within the intervention region. Social norms media marketing can be effective at changing drinking-related behaviors at the population level. This research provides a model for utilizing social norms media marketing to address other behaviors related to public health. 2010 Elsevier Ltd. All rights reserved.

  11. Effectiveness of social norms media marketing in reducing drinking and driving: A statewide campaign

    Science.gov (United States)

    Linkenbach, Jeffrey W.; Lewis, Melissa A.; Neighbors, Clayton

    2016-01-01

    This research evaluated the efficacy of a high-intensity social norms media marketing campaign aimed at correcting normative misperceptions and reducing the prevalence of drinking and driving among 21-to-34-year-olds in Montana. A quasi-experimental design was used, such that regions of Montana were assigned to one of three experimental groups: social norms media marketing campaign, buffer, and control. Four random samples of Montanans between the ages of 21 and 34 were assessed at four time points over 18 months via phone surveys. Findings suggest that the social norms media campaign was successful at exposing the targeted population to social norms messages in the counties within the intervention region. Moreover, results demonstrate the campaign reduced normative misperceptions, increased use of designated drivers, and decreased drinking and driving among those young adults in counties within the intervention region. Social norms media marketing can be effective at changing drinking-related behaviors at the population level. This research provides a model for utilizing social norms media marketing to address other behaviors related to public health. PMID:20619177

  12. Effects of platooning on signal-detection performance, workload, and stress: A driving simulator study.

    Science.gov (United States)

    Heikoop, Daniël D; de Winter, Joost C F; van Arem, Bart; Stanton, Neville A

    2017-04-01

    Platooning, whereby automated vehicles travel closely together in a group, is attractive in terms of safety and efficiency. However, concerns exist about the psychological state of the platooning driver, who is exempted from direct control, yet remains responsible for monitoring the outside environment to detect potential threats. By means of a driving simulator experiment, we investigated the effects on recorded and self-reported measures of workload and stress for three task-instruction conditions: (1) No Task, in which participants had to monitor the road, (2) Voluntary Task, in which participants could do whatever they wanted, and (3) Detection Task, in which participants had to detect red cars. Twenty-two participants performed three 40-min runs in a constant-speed platoon, one condition per run in counterbalanced order. Contrary to some classic literature suggesting that humans are poor monitors, in the Detection Task condition participants attained a high mean detection rate (94.7%) and a low mean false alarm rate (0.8%). Results of the Dundee Stress State Questionnaire indicated that automated platooning was less distressing in the Voluntary Task than in the Detection Task and No Task conditions. In terms of heart rate variability, the Voluntary Task condition yielded a lower power in the low-frequency range relative to the high-frequency range (LF/HF ratio) than the Detection Task condition. Moreover, a strong time-on-task effect was found, whereby the mean heart rate dropped from the first to the third run. In conclusion, participants are able to remain attentive for a prolonged platooning drive, and the type of monitoring task has effects on the driver's psychological state. Copyright © 2016 Elsevier Ltd. All rights reserved.

  13. Identifying Method of Drunk Driving Based on Driving Behavior

    Directory of Open Access Journals (Sweden)

    Xiaohua Zhao

    2011-05-01

    Full Text Available Drunk driving is one of the leading causes contributing to traffic crashes. There are numerous issues that need to be resolved with the current method of identifying drunk driving. Driving behavior, with the characteristic of real-time, was extensively researched to identify impaired driving behaviors. In this paper, the drives with BACs above 0.05% were defined as drunk driving state. A detailed comparison was made between normal driving and drunk driving. The experiment in driving simulator was designed to collect the driving performance data of the groups. According to the characteristics analysis for the effect of alcohol on driving performance, seven significant indicators were extracted and the drunk driving was identified by the Fisher Discriminant Method. The discriminant function demonstrated a high accuracy of classification. The optimal critical score to differentiate normal from drinking state was found to be 0. The evaluation result verifies the accuracy of classification method.

  14. Biliopancreatic Diversion: The Effectiveness of Duodenal Switch and Its Limitations

    Directory of Open Access Journals (Sweden)

    Blaire Anderson

    2013-01-01

    Full Text Available The prevalence of morbidly obese individuals is rising rapidly. Being overweight predisposes patients to multiple serious medical comorbidities including type two diabetes (T2DM, hypertension, dyslipidemia, and obstructive sleep apnea. Lifestyle modifications including diet and exercise produce modest weight reduction and bariatric surgery is the only evidence-based intervention with sustainable results. Biliopancreatic diversion (BPD produces the most significant weight loss with amelioration of many obesity-related comorbidities compared to other bariatric surgeries; however perioperative morbidity and mortality associated with this surgery are not insignificant; additionally long-term complications including undesirable gastrointestinal side effects and metabolic derangements cannot be ignored. The overall quality of evidence in the literature is low with a lack of randomized control trials, a preponderance of uncontrolled series, and small sample sizes in the studies available. Additionally, when assessing remission of comorbidities, definitions are unclear and variable. In this review we explore the pros and cons of BPD, a less well known and perhaps underutilized bariatric procedure.

  15. Metabolic Effects of Berries with Structurally Diverse Anthocyanins

    Directory of Open Access Journals (Sweden)

    John Overall

    2017-02-01

    Full Text Available Overconsumption of energy dense foods and sedentary lifestyle are considered as major causes of obesity-associated insulin resistance and abnormal glucose metabolism. Results from both cohort studies and randomized trials suggested that anthocyanins from berries may lower metabolic risks, however these reports are equivocal. The present study was designed to examine effects of six berries with structurally diverse anthocyanin profiles (normalized to 400 µg/g total anthocyanin content on development of metabolic risk factors in the C57BL/6 mouse model of polygenic obesity. Diets supplemented with blackberry (mono-glycosylated cyanidins, black raspberry (acylated mono-glycosylated cyanidins, blackcurrant (mono- and di-glycosylated cyanidins and delphinidins, maqui berry (di-glycosylated delphinidins, Concord grape (acylated mono-glycosylated delphinidins and petunidins, and blueberry (mono-glycosylated delphinidins, malvidins, and petunidins showed a prominent discrepancy between biological activities of delphinidin/malvidin-versus cyanidin-type anthocyanins that could be explained by differences in their structure and metabolism in the gut. Consumption of berries also resulted in a strong shift in the gastrointestinal bacterial communities towards obligate anaerobes that correlated with decrease in the gastrointestinal luminal oxygen and oxidative stress. Further work is needed to understand mechanisms that lead to nearly anoxic conditions in the gut lumens, including the relative contributions of host, diet and/or microbial oxidative activity, and their implication to human health.

  16. Diversity has stronger top-down than bottom-up effects on decomposition.

    Science.gov (United States)

    Srivastava, Diane S; Cardinale, Bradley J; Downing, Amy L; Duffy, J Emmett; Jouseau, Claire; Sankaran, Mahesh; Wright, Justin P

    2009-04-01

    The flow of energy and nutrients between trophic levels is affected by both the trophic structure of food webs and the diversity of species within trophic levels. However, the combined effects of trophic structure and diversity on trophic transfer remain largely unknown. Here we ask whether changes in consumer diversity have the same effect as changes in resource diversity on rates of resource consumption. We address this question by focusing on consumer-resource dynamics for the ecologically important process of decomposition. This study compares the top-down effect of consumer (detritivore) diversity on the consumption of dead organic matter (decomposition) with the bottom-up effect of resource (detrital) diversity, based on a compilation of 90 observations reported in 28 studies. We did not detect effects of either detrital or consumer diversity on measures of detrital standing stock, and effects on consumer standing stock were equivocal. However, our meta-analysis indicates that reductions in detritivore diversity result in significant reductions in the rate of decomposition. Detrital diversity has both positive and negative effects on decomposition, with no overall trend. This difference between top-down and bottom-up effects of diversity is robust to different effect size metrics and could not be explained by differences in experimental systems or designs between detritivore and detrital manipulations. Our finding that resource diversity has no net effect on consumption in "brown" (detritus-consumer) food webs contrasts with previous findings from "green" (plant-herbivore) food webs and suggests that effects of plant diversity on consumption may fundamentally change after plant death.

  17. Effects of space flight factors on genetic diversity of Buchloe ...

    African Journals Online (AJOL)

    Jane

    2011-10-05

    Oct 5, 2011 ... results for wheat coleoptiles, lettuce hypocotyls, and garden-cress ... space radiation dose for plant seeds at linear energy transfer (LET) space was 4.79 ... information content (PIC), total genetic diversity of materials i and j.

  18. COATING AND MANDREL EFFECTS ON FABRICATION OF GLOW DISCHARGE POLYMER NIF SCALE INDIRECT DRIVE CAPSULES

    International Nuclear Information System (INIS)

    NIKROO, A.; PONTELANDOLFO, J.M.; CASTILLO, E.R.

    2002-01-01

    OAK A271 COATING AND MANDREL EFFECTS ON FABRICATION OF GLOW DISCHARGE POLYMER NIF SCALE INDIRECT DRIVE CAPSULES. Targets for the National Ignition Facility (NIF) need to be about 200 (micro)m thick and 2 mm in diameter. These dimensions are well beyond those currently fabricated on a routine basis. They have investigated fabrication of near NIF scale targets using the depolymerizable mandrel technique. Poly-alpha-methylstyrene (PAMS) mandrels, about 2 mm in diameter, of varying qualities were coated with as much as 125 (micro)m of glow discharge polymer (GDP). The surface finish of the final shells was examined using a variety of techniques. A clear dependence of the modal spectrum of final GDP shell on the quality of the initial PAMS mandrels was observed. isolated features were found to be the greatest cause for a shell not meeting the NIF standard

  19. Facilitation drives the positive effects of plant richness on trace metal removal in a biodiversity experiment.

    Directory of Open Access Journals (Sweden)

    Jiang Wang

    Full Text Available BACKGROUND: Phytoextraction is an environmentally acceptable and inexpensive technique for mine tailing rehabilitation that uses metallophyte plants. These plants reduce the soil trace metal contents to environmentally acceptable levels by accumulating trace metals. Recently, whether more trace metals can be removed by species-rich communities of these plants received great attention, as species richness has been reported having positive effects on ecosystem functions. However, how the species richness affects trace metals removal of plant communities of mine tailing is rarely known. METHODOLOGY/PRINCIPAL FINDINGS: We examined the effects of species richness on soil trace metal removal in both natural and experimental plant communities. The root lengths and stem heights of each plant species were measured in order to calculate the functional diversity indices. Our results showed that trace metal (Cu, Cd, Pb and Zn concentrations in mine tailing soil declined as species richness increased in both the natural and experimental plant communities. Species richness, rather than functional diversity, positively affected the mineralomass of the experimental plant communities. The intensity of plant-plant facilitation increased with the species richness of experimental communities. Due to the incremental role of plant-plant facilitation, most of the species had higher biomasses, higher trace metal concentrations in their plant tissues and lower malondialdehyde concentrations in their leaves. Consequently, the positive effects of species richness on mineralomass were mostly attributable to facilitation among plants. CONCLUSIONS/SIGNIFICANCE: Our results provide clear evidence that, due to plant-plant facilitation, species richness positively affects the removal of trace metals from mine tailing soil through phytoextraction and provides further information on diversity conservation and environmental remediation in a mine tailing environment.

  20. Effects of complex life cycles on genetic diversity: cyclical parthenogenesis.

    Science.gov (United States)

    Rouger, R; Reichel, K; Malrieu, F; Masson, J P; Stoeckel, S

    2016-11-01

    Neutral patterns of population genetic diversity in species with complex life cycles are difficult to anticipate. Cyclical parthenogenesis (CP), in which organisms undergo several rounds of clonal reproduction followed by a sexual event, is one such life cycle. Many species, including crop pests (aphids), human parasites (trematodes) or models used in evolutionary science (Daphnia), are cyclical parthenogens. It is therefore crucial to understand the impact of such a life cycle on neutral genetic diversity. In this paper, we describe distributions of genetic diversity under conditions of CP with various clonal phase lengths. Using a Markov chain model of CP for a single locus and individual-based simulations for two loci, our analysis first demonstrates that strong departures from full sexuality are observed after only a few generations of clonality. The convergence towards predictions made under conditions of full clonality during the clonal phase depends on the balance between mutations and genetic drift. Second, the sexual event of CP usually resets the genetic diversity at a single locus towards predictions made under full sexuality. However, this single recombination event is insufficient to reshuffle gametic phases towards full-sexuality predictions. Finally, for similar levels of clonality, CP and acyclic partial clonality (wherein a fixed proportion of individuals are clonally produced within each generation) differentially affect the distribution of genetic diversity. Overall, this work provides solid predictions of neutral genetic diversity that may serve as a null model in detecting the action of common evolutionary or demographic processes in cyclical parthenogens (for example, selection or bottlenecks).

  1. Effectiveness of a Driving Intervention on Safe Community Mobility for Returning Combat Veterans

    Science.gov (United States)

    2016-05-01

    integration Deployment and  Driving • Combat Veterans (CV)  self ‐report (Lew et al. 2011; Zamorski & Kelley, 2012) – driving  fast and unpredictably...1, 2) a car and truck pull out in front of the driver, and (3) a lead vehicle brakes suddenly because of a cyclist. The drive also includes six...anxiety, potentially leading to driving errors. They include: (1) a car pulls out from the right and swerves, (2) a trash can located close to the

  2. Effects of electron cyclotron current drive on the evolution of double tearing mode

    International Nuclear Information System (INIS)

    Sun, Guanglan; Dong, Chunying; Duan, Longfang

    2015-01-01

    The effects of electron cyclotron current drive (ECCD) on the double tearing mode (DTM) in slab geometry are investigated by using two-dimensional compressible magnetohydrodynamics equations. It is found that, mainly, the double tearing mode is suppressed by the emergence of the secondary island, due to the deposition of driven current on the X-point of magnetic island at one rational surface, which forms a new non-complete symmetric magnetic topology structure (defined as a non-complete symmetric structure, NSS). The effects of driven current with different parameters (magnitude, initial time of deposition, duration time, and location of deposition) on the evolution of DTM are analyzed elaborately. The optimal magnitude or optimal deposition duration of driven current is the one which makes the duration of NSS the longest, which depends on the mutual effect between ECCD and the background plasma. Moreover, driven current introduced at the early Sweet-Parker phase has the best suppression effect; and the optimal moment also exists, depending on the duration of the NSS. Finally, the effects varied by the driven current disposition location are studied. It is verified that the favorable location of driven current is the X-point which is completely different from the result of single tearing mode

  3. Effects of electron cyclotron current drive on the evolution of double tearing mode

    Energy Technology Data Exchange (ETDEWEB)

    Sun, Guanglan, E-mail: sunguanglan@nciae.edu.cn; Dong, Chunying [Basic Science Section, North China Institute of Aerospace Engineering, Langfang 065000 (China); Duan, Longfang [School of Computer and Remote Sensing Information Technology, North China Institute of Aerospace Engineering, Langfang 065000 (China)

    2015-09-15

    The effects of electron cyclotron current drive (ECCD) on the double tearing mode (DTM) in slab geometry are investigated by using two-dimensional compressible magnetohydrodynamics equations. It is found that, mainly, the double tearing mode is suppressed by the emergence of the secondary island, due to the deposition of driven current on the X-point of magnetic island at one rational surface, which forms a new non-complete symmetric magnetic topology structure (defined as a non-complete symmetric structure, NSS). The effects of driven current with different parameters (magnitude, initial time of deposition, duration time, and location of deposition) on the evolution of DTM are analyzed elaborately. The optimal magnitude or optimal deposition duration of driven current is the one which makes the duration of NSS the longest, which depends on the mutual effect between ECCD and the background plasma. Moreover, driven current introduced at the early Sweet-Parker phase has the best suppression effect; and the optimal moment also exists, depending on the duration of the NSS. Finally, the effects varied by the driven current disposition location are studied. It is verified that the favorable location of driven current is the X-point which is completely different from the result of single tearing mode.

  4. Effects of fexofenadine and hydroxyzine on brake reaction time during car-driving with cellular phone use.

    Science.gov (United States)

    Tashiro, Manabu; Horikawa, Etsuo; Mochizuki, Hideki; Sakurada, Yumiko; Kato, Motohisa; Inokuchi, Takatoshi; Ridout, Fran; Hindmarch, Ian; Yanai, Kazuhiko

    2005-10-01

    Antihistamines are a mainstay treatment for allergic rhinitis; however, many older agents cause adverse events, including sedation and central nervous system (CNS) impairment. Research has shown sedating effects of antihistamines on driving; currently, no known study has examined whether cellular phone usage while driving further compounds impairment in individuals administered antihistamines. The aim of this study was to examine this endpoint. In a randomized, double-blind, placebo-controlled, three-way crossover study, healthy volunteers received fexofenadine HCl 120 mg, hydroxyzine HCl 30 mg and placebo. Brake reaction time (BRT) was used to examine driving performance across four conditions: driving only; driving while completing simple calculations; complex calculations; and conversing on a cellular phone. Subjective sedation assessments were also conducted. Brake reaction time with and without cellular phone usage in fexofenadine-treated subjects did not differ significantly from placebo in any condition. In contrast, hydroxyzine-treated subjects were significantly more sedated and had slower BRTs, suggesting slower hazard recognition and brake application, compared with the fexofenadine and placebo groups in all conditions. Importantly, cellular phone operation was an additive factor, increasing BRTs in hydroxyzine-treated volunteers. Fexofenadine did not impair CNS function in subjects involved in a divided attention task of driving and cellular phone operation. Copyright (c) 2005 John Wiley & Sons, Ltd.

  5. Distracted driving

    Science.gov (United States)

    ... including maps) The Dangers of Talking on the Phone While Driving You are four times more likely to get ... of reach. If you are caught using a phone while driving, you may risk a ticket or fine. Most ...

  6. Distracted Driving

    Science.gov (United States)

    ... and increased awareness of distracted driving using radio advertisements, news stories, and similar media. After the projects ... available at www.trafficsafetymarketing.gov . Distracted Driving Enforcement – TV Ads (Paid). For re-tagging, go to: www. ...

  7. Effects of an attractive wall on the translocation of polymer under driving

    International Nuclear Information System (INIS)

    Cao Weiping; Wang Chao; Sun Lizhen; Luo Mengbo

    2012-01-01

    The effects of an attractive wall at the trans side on the translocation of an eight-site bond-fluctuation model (BFM) polymer through a pore in a membrane under driving are simulated by the dynamic Monte Carlo method. The attractive wall shows two contrary effects: its excluded volume effect reduces configuration entropy and thus hinders the translocation of the polymer, while its attraction decreases the energy and thus accelerates the translocation. At a critical polymer-wall interaction ε* ≈- 1, we find that the two effects compensate each other and the translocation time τ is roughly independent of the separation distance between the wall and the pore. The value ε* ≈- 1 is roughly equal to the critical adsorption point for the BFM polymer. Moreover, the value of the critical attraction is roughly independent of chain length N and chemical potential difference Δμ. At last, a scaling relation τ ∼ N α is observed for polymer translocation at a high value of NΔμ. Though the translocation time is highly dependent on the polymer-wall interaction and pore-wall separation distance, the exponent α is always about 1.30 ± 0.05 so long as NΔμ is large enough. (paper)

  8. The effects of momentary visual disruption on hazard anticipation and awareness in driving.

    Science.gov (United States)

    Borowsky, Avinoam; Horrey, William J; Liang, Yulan; Garabet, Angela; Simmons, Lucinda; Fisher, Donald L

    2015-01-01

    Driver distraction is known to increase crash risk, especially when a driver glances inside the vehicle for especially long periods of time. Though it is clear that such glances increase the risk for the driver when looking inside the vehicle, it is less clear how these glances disrupt the ongoing processing of information outside the vehicle once the driver's eyes return to the road. The present study was aimed at exploring the effect of in-vehicle glances on the top-down processes that guide the detection and monitoring of hazards on the forward roadway. Using a driving simulator, 12 participants were monitored with an eye-tracking system while they navigated various hazardous scenarios. Six participants were momentarily interrupted by a visual secondary task (simulating a glance inside the vehicle) prior to the occurrence of a potential hazard and 6 were not. Eye movement analyses showed that interrupted drivers often failed to continue scanning for a potential hazard when their forward view reappeared, especially when the potential threat could not easily be localized. Additionally, drivers' self-appraisal of workload and performance of the driving task indicated that, contrary to what one might expect, drivers in the interruption condition reported workload levels lower than and performance equal to drivers in the no interruption condition. Drivers who are momentarily disrupted even for a brief duration are at risk of missing important information when they return their gaze to the forward roadway. In addition, because they are not aware of missing this information they are likely to continue engaging in in-vehicle tasks even though they are demonstrably unsafe. The implications for safety, calibration, and targeted remediation are discussed.

  9. On the way to pole position : The effect of tire grip on learning to drive a racecar

    NARCIS (Netherlands)

    De Groot, S.; De Winter, J.C.F.

    2011-01-01

    Racecar drivers could benefit from new training methods for learning to drive fast lap times. Inspired by the learning-from-errors principle, this simulator-based study investigated the effect of the tire-road friction coefficient on the training effectiveness of a car racing task. Three groups of

  10. Using driving simulators to assess driving safety.

    Science.gov (United States)

    Boyle, Linda Ng; Lee, John D

    2010-05-01

    Changes in drivers, vehicles, and roadways pose substantial challenges to the transportation safety community. Crash records and naturalistic driving data are useful for examining the influence of past or existing technology on drivers, and the associations between risk factors and crashes. However, they are limited because causation cannot be established and technology not yet installed in production vehicles cannot be assessed. Driving simulators have become an increasingly widespread tool to understand evolving and novel technologies. The ability to manipulate independent variables in a randomized, controlled setting also provides the added benefit of identifying causal links. This paper introduces a special issue on simulator-based safety studies. The special issue comprises 25 papers that demonstrate the use of driving simulators to address pressing transportation safety problems and includes topics as diverse as neurological dysfunction, work zone design, and driver distraction. Copyright (c) 2010 Elsevier Ltd. All rights reserved.

  11. Effect of audio in-vehicle red light-running warning message on driving behavior based on a driving simulator experiment.

    Science.gov (United States)

    Yan, Xuedong; Liu, Yang; Xu, Yongcun

    2015-01-01

    Drivers' incorrect decisions of crossing signalized intersections at the onset of the yellow change may lead to red light running (RLR), and RLR crashes result in substantial numbers of severe injuries and property damage. In recent years, some Intelligent Transport System (ITS) concepts have focused on reducing RLR by alerting drivers that they are about to violate the signal. The objective of this study is to conduct an experimental investigation on the effectiveness of the red light violation warning system using a voice message. In this study, the prototype concept of the RLR audio warning system was modeled and tested in a high-fidelity driving simulator. According to the concept, when a vehicle is approaching an intersection at the onset of yellow and the time to the intersection is longer than the yellow interval, the in-vehicle warning system can activate the following audio message "The red light is impending. Please decelerate!" The intent of the warning design is to encourage drivers who cannot clear an intersection during the yellow change interval to stop at the intersection. The experimental results showed that the warning message could decrease red light running violations by 84.3 percent. Based on the logistic regression analyses, drivers without a warning were about 86 times more likely to make go decisions at the onset of yellow and about 15 times more likely to run red lights than those with a warning. Additionally, it was found that the audio warning message could significantly reduce RLR severity because the RLR drivers' red-entry times without a warning were longer than those with a warning. This driving simulator study showed a promising effect of the audio in-vehicle warning message on reducing RLR violations and crashes. It is worthwhile to further develop the proposed technology in field applications.

  12. Effects of OROS-MPH Versus Dl-Amphetamine-XR on Driving Performance of ADHD Adolescents

    Directory of Open Access Journals (Sweden)

    J Gordon Millichap

    2006-10-01

    Full Text Available Driving performance of 35 adolescent ADHD patients (19 boys/16 girls; mean age 17.8 years on a driving simulator was compared while taking OROS methylphenidate (Concerta, 72 mg, mixed dl-amphetamine salts (Adderall XR, 30 mg, or placebo in a randomized, double-blind, crossover study at University of Virginia, Charlottesville.

  13. Driver support and automated driving systems : Acceptance and effects on behavior

    NARCIS (Netherlands)

    De Waard, D.; Brookhuis, K.A.; Scerbo, MW; Mouloua, M

    1999-01-01

    Automation in driving ranges from simple in-vehicle information systems to completely automated driving in the Automated Highway System (AHS). An increased level of automation and increased restriction in behavioural freedom, as well as decreased control over tasks, have serious consequences for

  14. Effects of balanced and unbalanced voltage sags on DC adjustable-speed drives

    Energy Technology Data Exchange (ETDEWEB)

    Pedra, Joaquin; Sainz, Luis; Corcoles, Felipe; Bergas, Joan [Department of Electrical Engineering, ETSEIB-UPC, Av. Diagonal, 647, 08028 Barcelona (Spain); de Blas, Alfredo [Department of Electrical Engineering, EUETIB-UPC, C. d' Urgell, 187, 08036 Barcelona (Spain)

    2008-06-15

    This paper analyzes the sensitivity of DC adjustable-speed drives to balanced and unbalanced voltage sags. The influence of sag type, depth, duration and phase-angle jump on DC drives is studied. The control of the DC drive has been taken into account to understand drive behavior in the presence of voltage sags. Two working modes of the DC motor are considered in the study: as a consumer load and as a regenerative load. When the DC motor works as a consumer load, the study shows that sag type and depth have a significant influence on drive behavior. However, the voltage sag can be ridden through if the rectifier firing angle is set correctly by the control. When the DC motor works as a regenerative load, the study shows the consequences of the three-phase rectifier commutation failure due to the voltage sag. (author)

  15. Electric drives

    CERN Document Server

    Boldea, Ion

    2005-01-01

    ENERGY CONVERSION IN ELECTRIC DRIVESElectric Drives: A DefinitionApplication Range of Electric DrivesEnergy Savings Pay Off RapidlyGlobal Energy Savings Through PEC DrivesMotor/Mechanical Load MatchMotion/Time Profile MatchLoad Dynamics and StabilityMultiquadrant OperationPerformance IndexesProblemsELECTRIC MOTORS FOR DRIVESElectric Drives: A Typical ConfigurationElectric Motors for DrivesDC Brush MotorsConventional AC MotorsPower Electronic Converter Dependent MotorsEnergy Conversion in Electric Motors/GeneratorsPOWER ELECTRONIC CONVERTERS (PECs) FOR DRIVESPower Electronic Switches (PESs)The

  16. Effect of Wave Accessibility on Lower Hybrid Wave Current Drive in Experimental Advanced Superconductor Tokamak with H-Mode Operation

    International Nuclear Information System (INIS)

    Li Xin-Xia; Xiang Nong; Gan Chun-Yun

    2015-01-01

    The effect of the wave accessibility condition on the lower hybrid current drive in the experimental advanced superconductor Tokamak (EAST) plasma with H-mode operation is studied. Based on a simplified model, a mode conversion layer of the lower hybrid wave between the fast wave branch and the slow wave branch is proved to exist in the plasma periphery for typical EAST H-mode parameters. Under the framework of the lower hybrid wave simulation code (LSC), the wave ray trajectory and the associated current drive are calculated numerically. The results show that the wave accessibility condition plays an important role on the lower hybrid current drive in EAST plasma. For wave rays with parallel refractive index n ‖ = 2.1 or n ‖ = 2.5 launched from the outside midplane, the wave rays may penetrate the core plasma due to the toroidal geometry effect, while numerous reflections of the wave ray trajectories in the plasma periphery occur. However, low current drive efficiency is obtained. Meanwhile, the wave accessibility condition is improved if a higher confined magnetic field is applied. The simulation results show that for plasma parameters under present EAST H-mode operation, a significant lower hybrid wave current drive could be obtained for the wave spectrum with peak value n ‖ = 2.1 if a toroidal magnetic field B T = 2.5 T is applied. (paper)

  17. Effect of large weirs on abundance and diversity of migratory ...

    African Journals Online (AJOL)

    Lake Tana has a remarkable fish diversity, including 17 endemic Labeobarbus species, of which nine spawn in the inflowing rivers. Three of the migratory species are threatened, namely the endangered Labeobarbus macrophtalmus and the vulnerable L. acutirostris and L. platydorsus. In July–November 2016 during the ...

  18. Using Video Effectively in Diverse Classes: What Students Want

    Science.gov (United States)

    Fee, Anthony; Budde-Sung, Amanda E. K.

    2014-01-01

    This article presents the findings of an exploratory study into the perceptions of a culturally and linguistically diverse cohort of management students (n = 236) about the use of video as a teaching and learning tool. The results show that while students are generally favorable toward audiovisual materials, the choice of content, how the medium…

  19. Psychometric Evaluation of Lexical Diversity Indices: Assessing Length Effects

    Science.gov (United States)

    Fergadiotis, Gerasimos; Wright, Heather Harris; Green, Samuel B.

    2015-01-01

    Purpose: Several novel techniques have been developed recently to assess the breadth of a speaker's vocabulary exhibited in a language sample. The specific aim of this study was to increase our understanding of the validity of the scores generated by different lexical diversity (LD) estimation techniques. Four techniques were explored: D, Maas,…

  20. The elusive effects of workplace diversity on innovation

    NARCIS (Netherlands)

    Ozgen, Ceren; Nijkamp, Peter; Poot, Jacques

    2017-01-01

    We investigate econometrically whether cultural diversity at the workplace boosts innovation. Our longitudinal linked employer-employee data combines two innovation surveys, with Dutch administrative, tax and regional data. We analyse the determinants of a firm's product and process innovations with

  1. Optimizing Board Effectiveness with Gender Diversity : Are Quotas the Answer?

    OpenAIRE

    Annemarie Durbin

    2011-01-01

    Women are underrepresented on corporate boards but are quotas the answer? Not according to the author. Annemarie Durbin cites evidence that using quotas to increase female representation can lead to tokenism, diminish the overall value of diversity on boards, affect board dynamics, and potentially lead to diluted commitments from existing female board directors. She recommends that, instea...

  2. Effects of large herbivores on grassland arthropod diversity

    NARCIS (Netherlands)

    van Klink, R.; van der Plas, F.; van Noordwijk, C. G. E. (Toos); WallisDeVries, M. F.; Olff, H.

    Both arthropods and large grazing herbivores are important components and drivers of biodiversity in grassland ecosystems, but a synthesis of how arthropod diversity is affected by large herbivores has been largely missing. To fill this gap, we conducted a literature search, which yielded 141

  3. Does order matter? Investigating the effect of sequence on glance duration during on-road driving.

    Directory of Open Access Journals (Sweden)

    Joonbum Lee

    Full Text Available Previous literature has shown that vehicle crash risks increases as drivers' off-road glance duration increases. Many factors influence drivers' glance duration such as individual differences, driving environment, or task characteristics. Theories and past studies suggest that glance duration increases as the task progresses, but the exact relationship between glance sequence and glance durations is not fully understood. The purpose of this study was to examine the effect of glance sequence on glance duration among drivers completing a visual-manual radio tuning task and an auditory-vocal based multi-modal navigation entry task. Eighty participants drove a vehicle on urban highways while completing radio tuning and navigation entry tasks. Forty participants drove under an experimental protocol that required three button presses followed by rotation of a tuning knob to complete the radio tuning task while the other forty participants completed the task with one less button press. Multiple statistical analyses were conducted to measure the effect of glance sequence on glance duration. Results showed that across both tasks and a variety of statistical tests, glance sequence had inconsistent effects on glance duration-the effects varied according to the number of glances, task type, and data set that was being evaluated. Results suggest that other aspects of the task as well as interface design effect glance duration and should be considered in the context of examining driver attention or lack thereof. All in all, interface design and task characteristics have a more influential impact on glance duration than glance sequence, suggesting that classical design considerations impacting driver attention, such as the size and location of buttons, remain fundamental in designing in-vehicle interfaces.

  4. Verbal collision avoidance messages during simulated driving: perceived urgency, alerting effectiveness and annoyance.

    Science.gov (United States)

    Baldwin, Carryl L

    2011-04-01

    Matching the perceived urgency of an alert with the relative hazard level of the situation is critical for effective alarm response. Two experiments describe the impact of acoustic and semantic parameters on ratings of perceived urgency, annoyance and alerting effectiveness and on alarm response speed. Within a simulated driving context, participants rated and responded to collision avoidance system (CAS) messages spoken by a female or male voice (experiments 1 and 2, respectively). Results indicated greater perceived urgency and faster alarm response times as intensity increased from -2 dB signal to noise (S/N) ratio to +10 dB S/N, although annoyance ratings increased as well. CAS semantic content interacted with alarm intensity, indicating that at lower intensity levels participants paid more attention to the semantic content. Results indicate that both acoustic and semantic parameters independently and interactively impact CAS alert perceptions in divided attention conditions and this work can inform auditory alarm design for effective hazard matching. Matching the perceived urgency of an alert with the relative hazard level of the situation is critical for effective alarm response. Here, both acoustic and semantic parameters independently and interactively impacted CAS alert perceptions in divided attention conditions. This work can inform auditory alarm design for effective hazard matching. STATEMENT OF RELEVANCE: Results indicate that both acoustic parameters and semantic content can be used to design collision warnings with a range of urgency levels. Further, these results indicate that verbal warnings tailored to a specific hazard situation may improve hazard-matching capabilities without substantial trade-offs in perceived annoyance.

  5. Environmental conditions influence the plant functional diversity effect on potential denitrification.

    Directory of Open Access Journals (Sweden)

    Ariana E Sutton-Grier

    2011-02-01

    Full Text Available Global biodiversity loss has prompted research on the relationship between species diversity and ecosystem functioning. Few studies have examined how plant diversity impacts belowground processes; even fewer have examined how varying resource levels can influence the effect of plant diversity on microbial activity. In a field experiment in a restored wetland, we examined the role of plant trait diversity (or functional diversity, (FD and its interactions with natural levels of variability of soil properties, on a microbial process, denitrification potential (DNP. We demonstrated that FD significantly affected microbial DNP through its interactions with soil conditions; increasing FD led to increased DNP but mainly at higher levels of soil resources. Our results suggest that the effect of species diversity on ecosystem functioning may depend on environmental factors such as resource availability. Future biodiversity experiments should examine how natural levels of environmental variability impact the importance of biodiversity to ecosystem functioning.

  6. Diversity effect in category-based inductive reasoning of young children: evidence from two methods.

    Science.gov (United States)

    Zhong, Luojin; Lee, Myung Sook; Huang, Yulan; Mo, Lei

    2014-02-01

    Previous studies have shown that diverse pieces of evidence, rather than similar pieces of evidence, are considered to have greater strength in adults' inductive reasoning. However, this diversity effect is inconsistently recognized by children. Three experiments using the same materials but different tasks examined whether young children consider the diversity principle in their reasoning. Although Experiment 1 applied a data selection task showed five-year-old children in both China and Korea were not sensitive to the diversity of evidence, Experiments 2 and 3 employed an identification task and demonstrated that children as young as five years were sensitive to diverse evidence. These findings indicated that young children, less than nine years of age, may have diversity effect. Methodological and cultural differences were discussed.

  7. Effects of Eco-Drive Education on the Reduction of Fuel Consumption and CO2 Emissions

    OpenAIRE

    Barić, Danijela; Zovak, Goran; Periša, Marko

    2013-01-01

    Sustainable mobility is the basic and long-term goal of the traffic policy. Eco-driving represents one of 40 measures that should by 2050 contribute to 60% of traffic-generated emission reduction. The paper presents the significance of educating the drivers about eco-driving as well as eco-drive training with the aim of reducing fuel consumption and CO2 emission. During research the drivers were tested in three cycles, prior to education, immediately following the education and eco-training a...

  8. The effect of feedback on attitudes toward cellular phone use while driving: a comparison between novice and experienced drivers.

    Science.gov (United States)

    Wang, Ying; Zhang, Wei; Reimer, Bryan; Lavallière, Martin; Lesch, Mary F; Horrey, William J; Wu, Su

    2010-10-01

    To assess and compare the effectiveness of a simulation-based approach to change drivers' attitudes toward cellular phone use while driving for younger novice and older experienced drivers. Thirty young novice drivers were tested on a driving simulator in this study. Their performance in dealing with driving tasks was measured for a single task and dual tasks (driving while using a cellular phone) and compared to 30 older experienced drivers tested previously in another study. Half of the younger drivers received video-based feedback regarding their performance in the two conditions, with an emphasis on the contribution of dual-tasking to degraded performance. The other half did not receive any performance feedback. Drivers' perceptions and attitudes toward cellular phone use while driving were investigated by a questionnaire before, immediately after, and again one month following the simulation-based testing for both groups of drivers (feedback; no feedback). All drivers (including the novice and experienced) reported willingness to engage in driving and talking on a cellular phone in some situations. The simulated driving test showed that a secondary cellular phone task significantly degraded driving performance for both the novice and the experienced drivers. The feedback treatment group (both the novice and the experienced) showed significant attitude change toward cellular phone use while driving (toward being less favorable), whereas the control group had no attitude change. At the one-month follow-up, the benefit of feedback was sustained more so in the experienced driver group than the novice driver group, although both groups still benefited relative to the control conditions. Simulation-based feedback training is promising for short-term education in novice drivers but may be more effective in the long-term for drivers with higher levels of experience. Drivers with more experience appear to have a greater, more sustained benefit from the training than

  9. Effect of widespread agricultural chemical use on butterfly diversity across Turkish provinces.

    Science.gov (United States)

    Pekin, Burak K

    2013-12-01

    Although agricultural intensification is thought to pose a significant threat to species, little is known about its role in driving biodiversity loss at regional scales. I assessed the effects of a major component of agricultural intensification, agricultural chemical use, and land-cover and climatic variables on butterfly diversity across 81 provinces in Turkey, where agriculture is practiced extensively but with varying degrees of intensity. I determined butterfly species presence in each province from data on known butterfly distributions and calculated agricultural chemical use as the proportion of agricultural households that use chemical fertilizers and pesticides. I used constrained correspondence analyses and regression-based multimodel inference to determine the effect of environmental variables on species composition and richness, respectively. The variation in butterfly species composition across the provinces was largely explained (78%) by the combination of agricultural chemical use, particularly pesticides, and climatic and land-cover variables. Although overall butterfly richness was primarily explained by climatic and land-cover variables, such as the area of natural vegetation cover, threatened butterfly richness and the relative number of threatened butterfly species decreased substantially as the proportion of agricultural households using pesticides increased. These findings suggest that widespread use of agricultural chemicals, or other components of agricultural intensification that may be collinear with pesticide use, pose an imminent threat to the biodiversity of Turkey. Accordingly, policies that mitigate agricultural intensification and promote low-input farming practices are crucial for protecting threatened species from extinction in rapidly industrializing nations such as Turkey. Efectos del Uso Extensivo de Agroquímicos sobre la Diversidad de Mariposas en Provincias Turcas. © 2013 Society for Conservation Biology.

  10. Harnessing demographic differences in organizations: What moderates the effects of workplace diversity?

    Science.gov (United States)

    Dawson, Jeremy F.; Otaye‐Ebede, Lilian; Woods, Stephen A.; West, Michael A.

    2015-01-01

    Summary To account for the double‐edged nature of demographic workplace diversity (i.e,. relational demography, work group diversity, and organizational diversity) effects on social integration, performance, and well‐being‐related variables, research has moved away from simple main effect approaches and started examining variables that moderate these effects. While there is no shortage of primary studies of the conditions under which diversity leads to positive or negative outcomes, it remains unclear which contingency factors make it work. Using the Categorization‐Elaboration Model as our theoretical lens, we review variables moderating the effects of workplace diversity on social integration, performance, and well‐being outcomes, focusing on factors that organizations and managers have control over (i.e., strategy, unit design, human resource, leadership, climate/culture, and individual differences). We point out avenues for future research and conclude with practical implications. © 2015 The Authors. Journal of Organizational Behavior published by John Wiley & Sons, Ltd PMID:28239234

  11. Harnessing demographic differences in organizations: What moderates the effects of workplace diversity?

    Science.gov (United States)

    Guillaume, Yves R F; Dawson, Jeremy F; Otaye-Ebede, Lilian; Woods, Stephen A; West, Michael A

    2017-02-01

    To account for the double-edged nature of demographic workplace diversity (i.e,. relational demography, work group diversity, and organizational diversity) effects on social integration, performance, and well-being-related variables, research has moved away from simple main effect approaches and started examining variables that moderate these effects. While there is no shortage of primary studies of the conditions under which diversity leads to positive or negative outcomes, it remains unclear which contingency factors make it work. Using the Categorization-Elaboration Model as our theoretical lens, we review variables moderating the effects of workplace diversity on social integration, performance, and well-being outcomes, focusing on factors that organizations and managers have control over (i.e., strategy, unit design, human resource, leadership, climate/culture, and individual differences). We point out avenues for future research and conclude with practical implications. © 2015 The Authors. Journal of Organizational Behavior published by John Wiley & Sons, Ltd.

  12. THE IMPACT OF WORKFORCE DIVERSITY ON ORGANIZATIONAL EFFECTIVENESS: A STUDY OF A NIGERIAN BANK

    Directory of Open Access Journals (Sweden)

    OMANKHANLEN ALEX EHIMARE

    2011-01-01

    Full Text Available It is generally recognized that there is diversity in the workforce of any enterprise, be it business, government, or civil society. This study therefore seeks to find out the impact of workforce diversity on organizational effectiveness using a Nigerian bank for the study. We used the Blau’s1977 index of heterogeneity to measure the diversity index. While asset growth for the year 2008 and 2009, using 2007 and 2008 as base year was used to measure the growth strategy. To determine group diversity and performance outcomes moderated by workgroup context, a series of hierarchical regression analysis were conducted. The study finds significant correlation between some of the diversity variables as well as individual diversity variables with the measures of organizational effectiveness. Also it reveals that gender and ethnicity are negatively related to both employee productivity and performance bonus. In addition the study find that gender, age and tenure diversities are positively correlated and are significantly related. It is recommended that company executives use good strategies to effectively manage workforce diversity and collaborative research efforts should be done to ascertain the contextual variables that moderate workforce diversity to produce positive performance outcomes.

  13. The Effects of Transcranial Direct Current Stimulation (tDCS on Psychomotor and Visual Perception Functions Related to Driving Skills

    Directory of Open Access Journals (Sweden)

    Alexander Brunnauer

    2018-01-01

    Full Text Available Objective: It could be demonstrated that anodal transcranial direct current stimulation (tDCS of the left dorsolateral prefrontal cortex (DLPFC enhances accuracy in working memory tasks and reaction time in healthy adults and thus may also have an influence on complex everyday tasks like driving a car. However, no studies have applied tDCS to psychomotor skills related to a standard driving test so far.Methods: 10 female and 5 male healthy adults without any medication and history of psychiatric or neurological illness were randomly assigned to two groups receiving active and sham stimulation in a double blind, cross-over study design. Standardized computerized psychomotor tests according to the German guidelines for road and traffic safety were administered at baseline. Then they performed the same tests during an anodal or sham tDCS of the left DLPFC in two separated sessions.Results: No significant improvements in skills related to driving performance like visual perception, stress tolerance, concentration, and vigilance could be shown after left anodal prefrontal tDCS. Side effects were low and did not differ between active and sham stimulation.Conclusions: The findings of our study indicate that left prefrontal tDCS may not alter driving skills affording more automated action patterns but as shown in previous studies may have an influence on driving behavior requiring executive control processes. This however has to be proved in future studies and within greater samples.

  14. Effect of police mobile computer terminal interface design on officer driving distraction.

    Science.gov (United States)

    Zahabi, Maryam; Kaber, David

    2018-02-01

    Several crash reports have identified in-vehicle distraction to be a primary cause of emergency vehicle crashes especially in law enforcement. Furthermore, studies have found that mobile computer terminals (MCTs) are the most frequently used in-vehicle technology for police officers. Twenty police officers participated in a driving simulator-based assessment of visual behavior, performance, workload and situation awareness with current and enhanced MCT interface designs. In general, results revealed MCT use while driving to decrease officer visual attention to the roadway, but usability improvements can reduce the level of visual distraction and secondary-task completion time. Results also suggest that use of MCTs while driving significantly reduces perceived level of driving environment awareness for police officers and increases cognitive workload. These findings may be useful for MCT manufacturers in improving interface designs to increase police officer and civilian safety. Copyright © 2017 Elsevier Ltd. All rights reserved.

  15. Human Factors of Automated Driving : Predicting the Effects of Authority Transitions on Traffic Flow Efficiency

    NARCIS (Netherlands)

    Varotto, S.F.; Hoogendoorn, R.G.; Van Arem, B.; Hoogendoorn, S.P.

    2014-01-01

    Automated driving potentially has a significant impact on traffic flow efficiency. Automated vehicles, which possess cooperative capabilities, are expected to reduce congestion levels for instance by increasing road capacity, by anticipating traffic conditions further downstream and also by

  16. RodPilotR - The Innovative and Cost-Effective Digital Control Rod Drive Control System for PWRs

    International Nuclear Information System (INIS)

    Baron, Clemens

    2008-01-01

    With RodPilot, AREVA NP offers an innovative and cost-effective system for controlling control rods in Pressurized Water Reactors. RodPilot controls the three operating coils of the control rod drive mechanism (lift, moveable gripper and stationary gripper coil). The rods are inserted into or withdrawn from the core as required by the Reactor Control System. The system combines modern components, state-of-the-art logic and a proven electronic control rod drive control principle to provide enhanced reliability and lower maintenance costs. (author)

  17. RodPilot{sup R} - The Innovative and Cost-Effective Digital Control Rod Drive Control System for PWRs

    Energy Technology Data Exchange (ETDEWEB)

    Baron, Clemens [AREVA NP GmbH, NLEE-G, Postfach 1199, 91001 Erlangen (Germany)

    2008-07-01

    With RodPilot, AREVA NP offers an innovative and cost-effective system for controlling control rods in Pressurized Water Reactors. RodPilot controls the three operating coils of the control rod drive mechanism (lift, moveable gripper and stationary gripper coil). The rods are inserted into or withdrawn from the core as required by the Reactor Control System. The system combines modern components, state-of-the-art logic and a proven electronic control rod drive control principle to provide enhanced reliability and lower maintenance costs. (author)

  18. Effect Chameleon. The Art of Negotiating the Diversity

    Directory of Open Access Journals (Sweden)

    Raquel Cantos Vicent

    2009-08-01

    Full Text Available This document intends to give notice of a youth participation experience mainly characterized by its inclusive attention in all the intervention process. Its outstanding intention was, from the beginning, to stir into action a participation space that accepted and contemplated as much diversity as possible. It is overall, a purpose to put in practise the theories defending the management of differences from common interest, the exercise of shared citizenship and not from the creation of specified resources and spaces.

  19. Effects of alcohol (BAC 0.5‰) and ecstasy (MDMA 100 mg) on simulated driving performance and traffic safety

    NARCIS (Netherlands)

    Veldstra, J.L.; Brookhuis, K.A.; De Waard, D.; Molmans, B.H.W.; Verstraete, A.G.; Skopp, G.; Janstos, R.

    2012-01-01

    Rational An increasing number of fatal road-accidents have been reported in which ecstasy was found in the blood of drivers. Although, ecstasy is frequently found to have been used in combination with alcohol, studies on the acute effects of ecstasy co-administered with alcohol on driving

  20. Automated driving and its effects on the safety ecosystem: How do compatibility issues affect the transition period?

    NARCIS (Netherlands)

    van Loon, R.J.; Martens, Marieke Hendrikje

    2015-01-01

    Different components of automated vehicles are being made available commercially as we speak. Much research has been conducted into these components and many of these have been studied with respect to their effects on safety, but the transition period from non-automated driving to fully automated

  1. Automated driving and its effect on the safety ecosystem: how do compatibility issues affect the transition period?

    NARCIS (Netherlands)

    Loon, R.J. van; Martens, M.H.

    2015-01-01

    Different components of automated vehicles are being made available commercially as we speak. Much research has been conducted into these components and many of these have been studied with respect to their effects on safety, but the transition period from non-automated driving to fully automated

  2. Effects of adaptive cruise control and highly automated driving on workload and situation awareness : A review of the empirical evidence

    NARCIS (Netherlands)

    Winter, J.C.F. de; Happee, R.; Martens, M.H.; Stanton, N.A.

    2014-01-01

    Adaptive cruise control (ACC), a driver assistance system that controls longitudinal motion, has been introduced in consumer cars in 1995. A next milestone is highly automated driving (HAD), a system that automates both longitudinal and lateral motion. We investigated the effects of ACC and HAD on

  3. Effects of adaptive cruise control and highly automated driving on workload and situation awareness: A review of the empirical evidence.

    NARCIS (Netherlands)

    de Winter, Joost C.F.; Happee, Riender; Martens, Marieke Hendrikje; Stanton, Neville A.

    2014-01-01

    Adaptive cruise control (ACC), a driver assistance system that controls longitudinal motion, has been introduced in consumer cars in 1995. A next milestone is highly automated driving (HAD), a system that automates both longitudinal and lateral motion. We investigated the effects of ACC and HAD on

  4. Effects of Mothers against Drunk Driving's (MADD's) Victim Impact Panels on First-Time DWI Offenders: Some Initial Results.

    Science.gov (United States)

    Rao, Nagesh; And Others

    A study assessed the effects of victim impact panels (VIP) on first-time DWI (Driving While Intoxicated) offenders in Albuquerque, New Mexico. The VIP is an emotional presentation by the victim or their parents about how they were injured or their child was killed by a drunk driver. Subjects, 350 first-time offenders participated in a Mothers…

  5. Effects of local defect growth in direct-drive cryogenic implosions on OMEGA

    Energy Technology Data Exchange (ETDEWEB)

    Igumenshchev, I. V.; Shmayda, W. T.; Harding, D. R.; Sangster, T. C. [Laboratory for Laser Energetics, University of Rochester, 250 East River Road, Rochester, New York 14623-1299 (United States); Goncharov, V. N. [Laboratory for Laser Energetics, University of Rochester, 250 East River Road, Rochester, New York 14623-1299 (United States); Department of Mechanical Engineering, University of Rochester, Rochester, New York 14623 (United States); Meyerhofer, D. D. [Laboratory for Laser Energetics, University of Rochester, 250 East River Road, Rochester, New York 14623-1299 (United States); Department of Mechanical Engineering, University of Rochester, Rochester, New York 14623 (United States); Department of Physics and Astronomy, University of Rochester, Rochester, New York 14623 (United States)

    2013-08-15

    Spherically symmetric, low-adiabat (adiabat α ≲ 3) cryogenic direct-drive-implosion experiments on the OMEGA laser [T. R. Boehly et al., Opt. Commun. 133, 495 (1995)] yield less than 10% of the neutrons predicted in one-dimensional hydrodynamic simulations. Two-dimensional hydrodynamic simulations suggest that this performance degradation can be explained assuming perturbations from isolated defects of submicron to tens-of-micron scale on the outer surface or inside the shell of implosion targets. These defects develop during the cryogenic filling process and typically number from several tens up to hundreds for each target covering from about 0.2% to 1% of its surface. The simulations predict that such defects can significantly perturb the implosion and result in the injection of about 1 to 2 μg of the hot ablator (carbon-deuterium) and fuel (deuterium-tritium) materials from the ablation surface into the targets. Both the hot mass injection and perturbations of the shell reduce the final shell convergence ratio and implosion performance. The injected carbon ions radiatively cool the hot spot, reducing the fuel temperature, and further reducing the neutron yield. The negative effect of local defects can be minimized by decreasing the number and size of these defects and/or using more hydrodynamically stable implosion designs with higher shell adiabat.

  6. Effect on energy use and greenhouse micro climate through fan motor control by variable frequency drives

    International Nuclear Information System (INIS)

    Teitel, Meir; Zhao Yun; Barak, Moti; Bar-lev, Eli; Shmuel, David

    2004-01-01

    A comparison was conducted between ON-OFF and variable frequency drive (VFD) systems to control greenhouse ventilation fans. The study aimed to determine the effect of each system on the energy consumption and resulting greenhouse micro climate. The experiments were conducted in a commercial size greenhouse in which pepper was grown. To check the performance of the fan that was controlled by a VFD system, it was installed in a test facility and operated under several rotation speeds. At each speed of rotation, the static pressure on the fan was changed and parameters, such as electricity consumption and air flow rate, were measured. Reducing the fan speed with the VFD system resulted in reductions in the air flow rate through the greenhouse and energy consumption, the latter being much more significant. The study showed that VFD control can reduce electricity consumption compared with ON-OFF operation by an amount that depends on the weather. In the present study, the average energy consumption with the VFD control system over a period of one month, was about 0.64 of that with an ON-OFF system. The average greenhouse daily air temperatures and humidity ratios obtained with each control system between 0700 and 1800 were nearly equal during that month. The results obtained in the greenhouse further show that the VFD system has a greater potential than the ON-OFF to reduce the range of amplitude variations in the air temperature and humidity ratio within the greenhouse

  7. Effect of supporting structure stiffness on the drive train assembly of an induced draft cooling tower under seismic effects

    International Nuclear Information System (INIS)

    Raghavan, N.; Ramasubramanian, S.; Khan, K.

    2005-01-01

    In a nuclear power project an induced draft cooling tower, as a safety-related structure and part of the main cooling system, has to perform satisfactorily under designated seismic effects. While the structural elements can be designed by conventional methods to ensure adequate safety, the seismic qualification of the mechanical components poses a challenge. The paper describes a methodology adopted for the seismic qualification of a typical Drive Train Assembly for the axial flow fan of an induced draft cooling tower, to ensure the structural integrity and functional operability of the assembly during Operating Base Earthquake and Safe Shutdown Earthquake conditions. This is achieved by performing a detailed finite element analysis of the rotating equipment assembly consisting of the electric motor, gear box and fan along with the drive shaft between the motor and the gear box. The various components are modeled using beam elements, plate elements and spring elements to idealize the flexible connections and supports. The floor response spectra derived from a dynamic analysis of the overall structure under stipulated seismic acceleration spectra are the main excitation inputs into the system. The results validate the adequacy of gaps for movement and the strengths of the couplings and bolts to withstand the applied loads. The assumed modeling and analysis methodology are seen to be acceptable procedures for seismic qualification of important components of the cooling tower. (authors)

  8. High Voltage Solar Array Arc Testing for a Direct Drive Hall Effect Thruster System

    Science.gov (United States)

    Schneider, Todd; Carruth, M. R., Jr.; Vaughn, J. A.; Jongeward, G. A.; Mikellides, I. G.; Ferguson, D.; Kerslake, T. W.; Peterson, T.; Snyder, D.; Hoskins, A.

    2004-01-01

    The deleterious effects of spacecraft charging are well known, particularly when the charging leads to arc events. The damage that results from arcing can severely reduce system lifetime and even cause critical system failures. On a primary spacecraft system such as a solar array, there is very little tolerance for arcing. Motivated by these concerns, an experimental investigation was undertaken to determine arc thresholds for a high voltage (200-500 V) solar array in a plasma environment. The investigation was in support of a NASA program to develop a Direct Drive Hall-Effect Thruster (D2HET) system. By directly coupling the solar array to a Hall-effect thruster, the D2HET program seeks to reduce mass, cost and complexity commonly associated with the power processing in conventional power systems. In the investigation, multiple solar array technologies and configurations were tested. The cell samples were biased to a negative voltage, with an applied potential difference between them, to imitate possible scenarios in solar array strings that could lead to damaging arcs. The samples were tested in an environment that emulated a low-energy, HET-induced plasma. Short duration trigger arcs as well as long duration sustained arcs were generated. Typical current and voltage waveforms associated with the arc events are presented. Arc thresholds are also defined in terms of voltage, current and power. The data will be used to propose a new, high-voltage (greater than 300 V) solar array design for which the likelihood of damage from arcing is minimal.

  9. Pile Driving

    Science.gov (United States)

    1987-01-01

    Machine-oriented structural engineering firm TERA, Inc. is engaged in a project to evaluate the reliability of offshore pile driving prediction methods to eventually predict the best pile driving technique for each new offshore oil platform. Phase I Pile driving records of 48 offshore platforms including such information as blow counts, soil composition and pertinent construction details were digitized. In Phase II, pile driving records were statistically compared with current methods of prediction. Result was development of modular software, the CRIPS80 Software Design Analyzer System, that companies can use to evaluate other prediction procedures or other data bases.

  10. THE EFFECT OF ORGANIC SEDIMENT CONTENT ON CORAL DIVERSITY IN KARIMUNJAWA ISLAND, INDONESIA

    Directory of Open Access Journals (Sweden)

    Fajar Nugroho

    2018-06-01

    Full Text Available Coral reef now are under threats due to sedimentation. Fatal effect of organic rich sediment, leading corals mortality. Therefore, the study was conducted to investigate effect of organic sediment content to the coral diversity in Karimunjawa Island, Central Java, Indonesia. Field data was conducted at 6 locations.  Three sediment traps were deployed at each sites to measure organic sediment content. Twenty replicated quadrant transects were used to estimate coral density and coral diversity. Analysis of variance (ANOVA was used to examine the differences of organic sediment content in each station. The linear regression was used to assess the relationship between organic sediment content and coral diversity. Our field result demonstrated that sediment content significantly different between sites with value range from 0.42 mg/800 ml - 1.32 mg/800 ml. Based on the Simson’s Diversity Index, the highest coral diversity found at Alang-alang as site with low sedimentation while the lowest coral diversity was found at Legon Lele as site with high sedimentation. The study shown significant negative correlation between organic sediment content and coral diversity with the coefficient of regression 0.68. This study convinces that disturbance on coral reefs might affect coral diversity in Karimunjawa Island, in addition to other factors such as the influence of human activities, natural disruption and climate change. Keywords: sedimentation, organic, coral, diversity, Karimunjawa

  11. Long-term effects of plant diversity and composition on soil nematode communities in grassland.

    NARCIS (Netherlands)

    Viketoft, M.; Bengtsson, J.; Sohlenius, B.; Berg, M.P.; Petchey, O.; Palmborg, C.; Huss-Daniel, K.

    2009-01-01

    An important component of plant-soil feedbacks is how plant species identity and diversity influence soil organism communities. We examine the effects of grassland plant species growing alone and together up to a richness of 12 species on nematode diversity and feeding group composition, eight years

  12. Changing Attitudes over Time: Assessing the Effectiveness of a Workplace Diversity Course

    Science.gov (United States)

    Probst, Tahira M.

    2003-01-01

    Diversity is increasing within the United States, and higher education will likely play a key role in preparing people to function in this new environment. This study assessed the effectiveness of a semester-long psychology workplace diversity course at changing student levels of ethnocentrism and attitudes regarding gender roles; the disabled;…

  13. Conservation of biodiversity in sugar pine: effects of the blister rust epidemic on genetic diversity

    Science.gov (United States)

    Constance I. Millar; Bohun B. Kinloch; Robert D. Westfall

    1992-01-01

    Genetic diversity in sugar plne will be severely reduced by the blister rust pandemic predicted within the next 50 to 75 years. We model effects of the epidemic on genetic diversity at the stand and landscape levels for both natural and artificial regeneration. In natural stands, because natural frequencies of the dominant gene (R) for resistance are low, the most...

  14. Commensal bacteria drive endogenous transformation and tumour stem cell marker expression through a bystander effect.

    Science.gov (United States)

    Wang, Xingmin; Yang, Yonghong; Huycke, Mark M

    2015-03-01

    Commensal bacteria and innate immunity play a major role in the development of colorectal cancer (CRC). We propose that selected commensals polarise colon macrophages to produce endogenous mutagens that initiate chromosomal instability (CIN), lead to expression of progenitor and tumour stem cell markers, and drive CRC through a bystander effect. Primary murine colon epithelial cells were repetitively exposed to Enterococcus faecalis-infected macrophages, or purified trans-4-hydroxy-2-nonenal (4-HNE)-an endogenous mutagen and spindle poison produced by macrophages. CIN, gene expression, growth as allografts in immunodeficient mice were examined for clones and expression of markers confirmed using interleukin (IL) 10 knockout mice colonised by E. faecalis. Primary colon epithelial cells exposed to polarised macrophages or 4-hydroxy-2-nonenal developed CIN and were transformed after 10 weekly treatments. In immunodeficient mice, 8 of 25 transformed clones grew as poorly differentiated carcinomas with 3 tumours invading skin and/or muscle. All tumours stained for cytokeratins confirming their epithelial cell origin. Gene expression profiling of clones showed alterations in 3 to 7 cancer driver genes per clone. Clones also strongly expressed stem/progenitor cell markers Ly6A and Ly6E. Although not differentially expressed in clones, murine allografts positively stained for the tumour stem cell marker doublecortin-like kinase 1. Doublecortin-like kinase 1 and Ly6A/E were expressed by epithelial cells in colon biopsies for areas of inflamed and dysplastic tissue from E. faecalis-colonised IL-10 knockout mice. These results validate a novel mechanism for CRC that involves endogenous CIN and cellular transformation arising through a microbiome-driven bystander effect. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

  15. The effects of electron cyclotron heating and current drive on toroidal Alfvén eigenmodes in tokamak plasmas

    Science.gov (United States)

    Sharapov, S. E.; Garcia-Munoz, M.; Van Zeeland, M. A.; Bobkov, B.; Classen, I. G. J.; Ferreira, J.; Figueiredo, A.; Fitzgerald, M.; Galdon-Quiroga, J.; Gallart, D.; Geiger, B.; Gonzalez-Martin, J.; Johnson, T.; Lauber, P.; Mantsinen, M.; Nabais, F.; Nikolaeva, V.; Rodriguez-Ramos, M.; Sanchis-Sanchez, L.; Schneider, P. A.; Snicker, A.; Vallejos, P.; the AUG Team; the EUROfusion MST1 Team

    2018-01-01

    Dedicated studies performed for toroidal Alfvén eigenmodes (TAEs) in ASDEX-Upgrade (AUG) discharges with monotonic q-profiles have shown that electron cyclotron resonance heating (ECRH) can make TAEs more unstable. In these AUG discharges, energetic ions driving TAEs were obtained by ion cyclotron resonance heating (ICRH). It was found that off-axis ECRH facilitated TAE instability, with TAEs appearing and disappearing on timescales of a few milliseconds when the ECRH power was switched on and off. On-axis ECRH had a much weaker effect on TAEs, and in AUG discharges performed with co- and counter-current electron cyclotron current drive (ECCD), the effects of ECCD were found to be similar to those of ECRH. Fast ion distributions produced by ICRH were computed with the PION and SELFO codes. A significant increase in T e caused by ECRH applied off-axis is found to increase the fast ion slowing-down time and fast ion pressure causing a significant increase in the TAE drive by ICRH-accelerated ions. TAE stability calculations show that the rise in T e causes also an increase in TAE radiative damping and thermal ion Landau damping, but to a lesser extent than the fast ion drive. As a result of the competition between larger drive and damping effects caused by ECRH, TAEs become more unstable. It is concluded, that although ECRH effects on AE stability in present-day experiments may be quite significant, they are determined by the changes in the plasma profiles and are not particularly ECRH specific.

  16. Effects of age and auditory and visual dual tasks on closed-road driving performance.

    Science.gov (United States)

    Chaparro, Alex; Wood, Joanne M; Carberry, Trent

    2005-08-01

    This study investigated how driving performance of young and old participants is affected by visual and auditory secondary tasks on a closed driving course. Twenty-eight participants comprising two age groups (younger, mean age = 27.3 years; older, mean age = 69.2 years) drove around a 5.1-km closed-road circuit under both single and dual task conditions. Measures of driving performance included detection and identification of road signs, detection and avoidance of large low-contrast road hazards, gap judgment, lane keeping, and time to complete the course. The dual task required participants to verbally report the sums of pairs of single-digit numbers presented through either a computer speaker (auditorily) or a dashboard-mounted monitor (visually) while driving. Participants also completed a vision and cognitive screening battery, including LogMAR visual acuity, Pelli-Robson letter contrast sensitivity, the Trails test, and the Digit Symbol Substitution (DSS) test. Drivers reported significantly fewer signs, hit more road hazards, misjudged more gaps, and increased their time to complete the course under the dual task (visual and auditory) conditions compared with the single task condition. The older participants also reported significantly fewer road signs and drove significantly more slowly than the younger participants, and this was exacerbated for the visual dual task condition. The results of the regression analysis revealed that cognitive aging (measured by the DSS and Trails test) rather than chronologic age was a better predictor of the declines seen in driving performance under dual task conditions. An overall z score was calculated, which took into account both driving and the secondary task (summing) performance under the two dual task conditions. Performance was significantly worse for the auditory dual task compared with the visual dual task, and the older participants performed significantly worse than the young subjects. These findings demonstrate

  17. Effects of elastic support on the dynamic behaviors of the wind turbine drive train

    Institute of Scientific and Technical Information of China (English)

    Shuaishuai WANG; Caichao ZHU; Chaosheng SONG; Huali HAN

    2017-01-01

    The reliability and service life of wind turbines are influenced by the complex loading applied on the hub,especially amidst a poor external wind environment.A three-point elastic support,which includes the main bearing and two torque arms,was considered in this study.Based on the flexibilities of the planet carrier and the housing,a coupled dynamic model was developed for a wind turbine drive train.Then,the dynamic behaviors of the drive train for different elastic support parameters were computed and analyzed.Frequency response functions were used to examine how different elastic support parameters influence the dynamic behaviors of the drive train.Results showed that the elastic support parameters considerably influenced the dynamic behaviors of the wind turbine drive train.A large support stiffness of the torque arms decreased the dynamic response of the planet carrier and the main bearing,whereas a large support stiffness of the main bearing decreased the dynamic response of planet carrier while increasing that of the main bearing.The findings of this study provide the foundation for optimizing the elastic support stiffness of the wind turbine drive train.

  18. The effect of non-inductive current drive on tokamak transport

    International Nuclear Information System (INIS)

    Helander, P; Akers, R J; Valovic, M; Peysson, Y

    2005-01-01

    Non-inductive current drive causes cross-field neoclassical transport in a tokamak, in much the same way that the toroidal electric field used to drive the plasma current produces the so-called Ware pinch. This transport can be either inwards or outwards, depending on the current drive mechanism, and can be either larger or smaller than the analogous Ware pinch. A Green's function formalism is used to calculate the transport produced by wave-driven currents, which is found to be inwards for electron-cyclotron and lower-hybrid current drive. Its magnitude is proportional to the collisionality of the current-carrying electrons and therefore smaller than the Ware pinch when the resonant electrons are suprathermal. In contrast, neutral-beam current drive produces outward particle transport when the beams are injected in the same toroidal direction as the plasma current, and inward particle transport otherwise. This transport is somewhat larger than the corresponding Ware pinch. Together, they may explain an observation made on several tokamaks over the years, most recently on MAST, that density profiles tend to be more peaked during counter-injection

  19. Effects of acute alcohol consumption on measures of simulated driving: A systematic review and meta-analysis.

    Science.gov (United States)

    Irwin, Christopher; Iudakhina, Elizaveta; Desbrow, Ben; McCartney, Danielle

    2017-05-01

    Driving simulators are used in a wide range of research settings to help develop an understanding of driver behavior in complex environments. Acute alcohol impairment is an important research topic for traffic safety and a large number of studies have indicated levels of simulated driving impairment imposed by alcohol across a range of performance outcome variables. The aim of the present study was to examine the impact of acute alcohol consumption on simulated driving performance by conducting a systematic review and meta-analysis of the available evidence. The online databases PubMed (MEDLINE), Web of Science (via Thomas Reuters) and Scopus were searched to identify studies that measured simulated car driving performance under control ('no alcohol' or 'placebo alcohol' ingestion) and intervention (acute alcohol ingestion) conditions, using repeated-measures experimental designs. Primary research outcomes were standard deviation of lane position (SDLP) and standard deviation of speed (SDSP); (total number of lane crossings (LC) and average speed (Speed) were secondary research outcomes). Meta-analytic procedures were used to quantify the effect of acute alcohol consumption on vehicle control, and to determine the influence of methodological variables (i.e. the duration of the simulated driving task, the limb of the BAC curve (ascending vs. descending) and the type of driving simulator employed (i.e. car vs. PC-based)) on the magnitude of the performance change due to alcohol consumption. 423 records were screened, and 50 repeated-measures trials (n=962 participants, 62% male) derived from 17 original publications were reviewed. 37 trials (n=721 participants) used a 'placebo alcohol' comparator to determine the effect of alcohol consumption on SDLP (32/37) and SDSP (22/37). Alcohol consumption significantly increased SDLP by 4.0±0.5cm (95% CI: 3.0, 5.1) and SDSP by 0.38±0.10km⋅h -1 (95% CI: 0.19, 0.57). Regression analyses indicate BAC (p=0.004) and driving

  20. Positive Neighborhood Norms Buffer Ethnic Diversity Effects on Neighborhood Dissatisfaction, Perceived Neighborhood Disadvantage, and Moving Intentions.

    Science.gov (United States)

    Van Assche, Jasper; Asbrock, Frank; Roets, Arne; Kauff, Mathias

    2018-05-01

    Positive neighborhood norms, such as strong local networks, are critical to people's satisfaction with, perceived disadvantage of, and intentions to stay in their neighborhood. At the same time, local ethnic diversity is said to be detrimental for these community outcomes. Integrating both frameworks, we tested whether the negative consequences of diversity occur even when perceived social norms are positive. Study 1 ( N = 1,760 German adults) showed that perceptions of positive neighborhood norms buffered against the effects of perceived diversity on moving intentions via neighborhood satisfaction and perceived neighborhood disadvantage. Study 2 ( N = 993 Dutch adults) replicated and extended this moderated mediation model using other characteristics of diversity (i.e., objective and estimated minority proportions). Multilevel analyses again revealed consistent buffering effects of positive neighborhood norms. Our findings are discussed in light of the ongoing public and political debate concerning diversity and social and communal life.

  1. Effect of driving voltage polarity on dynamic response characteristics of electrowetting liquid lens

    Science.gov (United States)

    Na, Xie; Ning, Zhang; Rong-Qing, Xu

    2018-05-01

    A test device is developed for studying the dynamic process of an electrowetting liquid lens. By analyzing the light signals through the liquid lens, the dynamical properties of the lens are investigated. In our experiment, three types of pulse, i.e., sine, bipolar pulse, and single pulse signals, are employed to drive the liquid lens, and the dynamic characteristics of the lens are subsequently analyzed. The results show that the positive and negative polarities of the driving voltage can cause a significant difference in the response of the liquid lens; meanwhile, the lens’s response to the negative polarity of the driving voltage is clearer. We use the theory of charge restraint to explain this phenomenon, and it is concluded that the negative ions are more easily restrained by a dielectric layer. This work gives direct guidance for practical applications based on an electrowetting liquid lens.

  2. Building Effective Pipelines to Increase Diversity in the Geosciences

    Science.gov (United States)

    Snow, E.; Robinson, C. R.; Neal-Mujahid, R.

    2017-12-01

    The U.S. Geological Survey (USGS) recognizes and understands the importance of a diverse workforce in advancing our science. Valuing Differences is one of the guiding principles of the USGS, and is the critical basis of the collaboration among the Youth and Education in Science (YES) program in the USGS Office of Science, Quality, and Integrity (OSQI), the Office of Diversity and Equal Opportunity (ODEO), and USGS science centers to build pipeline programs targeting diverse young scientists. Pipeline programs are robust, sustained relationships between two entities that provide a pathway from one to the other, in this case, from minority serving institutions to the USGS. The USGS has benefited from pipeline programs for many years. Our longest running program, with University of Puerto Rico Mayaguez (UPR), is a targeted outreach and internship program that has been managed by USGS scientists in Florida since the mid-1980's Originally begun as the Minority Participation in the Earth Sciences (MPES ) Program, it has evolved over the years, and in its several forms has brought dozens of interns to the USGS. Based in part on that success, in 2006 USGS scientists in Woods Hole MA worked with their Florida counterparts to build a pipeline program with City College of New York (CCNY). In this program, USGS scientists visit CCNY monthly, giving a symposium and meeting with students and faculty. The talks are so successful that the college created a course around them. In 2017, the CCNY and UPR programs brought 12 students to the USGS for summer internships. The CCNY model has been so successful that USGS is exploring creating similar pipeline programs. The YES office is coordinating with ODEO and USGS science centers to identify partner universities and build relationships that will lead to robust partnership where USGS scientists will visit regularly to engage with faculty and students and recruit students for USGS internships. The ideal partner universities will have a

  3. Effect of a powered drive on pushing and pulling forces when transporting bariatric hospital beds.

    Science.gov (United States)

    Wiggermann, Neal

    2017-01-01

    Powered drives designed to assist with moving hospital beds are commercially available but no studies have evaluated whether they reduce the push and pull forces likely contributing to injury in caregivers. This study measured hand forces of 10 caregivers maneuvering a manual and powered bariatric bed through simulated hospital environments (hallway, elevator, and ramp). Peak push and pull forces exceeded previously established psychophysical limits for all activities with the manual bed. For the powered bed, peak forces were significantly (p pushing did not differ between beds. Powered drive may reduce the risk of injury or the number of caregivers needed for transport. Copyright © 2016 Elsevier Ltd. All rights reserved.

  4. Disentangling the effects of species diversity, and intraspecific and interspecific tree size variation on aboveground biomass in dry zone homegarden agroforestry systems.

    Science.gov (United States)

    Ali, Arshad; Mattsson, Eskil

    2017-11-15

    The biodiversity - aboveground biomass relationship has been intensively studied in recent decades. However, no consensus has been arrived to consider the interplay of species diversity, and intraspecific and interspecific tree size variation in driving aboveground biomass, after accounting for the effects of plot size heterogeneity, soil fertility and stand quality in natural forest including agroforests. We tested the full, partial and no mediations effects of species diversity, and intraspecific and interspecific tree size variation on aboveground biomass by employing structural equation models (SEMs) using data from 45 homegarden agroforestry systems in Sri Lanka. The full mediation effect of either species diversity or intraspecific and interspecific tree size variation was rejected, while the partial and no mediation effects were accepted. In the no mediation SEM, homegarden size had the strongest negative direct effect (β=-0.49) on aboveground biomass (R 2 =0.65), followed by strong positive direct effect of intraspecific tree size variation (β=0.32), species diversity (β=0.29) and interspecific tree size variation (β=0.28). Soil fertility had a negative direct effect on interspecific tree size variation (β=-0.31). Stand quality had a significant positive total effect on aboveground biomass (β=0.28), but homegarden size had a significant negative total effect (β=-0.62), while soil fertility had a non-significant total effect on aboveground biomass. Similar to the no mediation SEM, the partial mediation SEMs had explained almost similar variation in aboveground biomass because species diversity, and intraspecific and interspecific tree size variation had non-significant indirect effects on aboveground biomass via each other. Our results strongly suggest that a multilayered tree canopy structure, due to high intraspecific and interspecific tree size variation, increases light capture and efficient utilization of resources among component species, and

  5. Medications and impaired driving.

    Science.gov (United States)

    Hetland, Amanda; Carr, David B

    2014-04-01

    To describe the association of specific medication classes with driving outcomes and provide clinical recommendations. The MEDLINE and EMBASE databases were searched for articles published from January 1973 to June 2013 on classes of medications associated with driving impairment. The search included outcome terms such as automobile driving, motor vehicle crash, driving simulator, and road tests. Only English-language articles that contained findings from observational or interventional designs with ≥ 10 participants were included in this review. Cross-sectional studies, case series, and case reports were excluded. Driving is an important task and activity for the majority of adults. Some commonly prescribed medications have been associated with driving impairment measured by road performance, driving simulation, and/or motor vehicle crashes. This review of 30 studies identified findings with barbiturates, benzodiazepines, hypnotics, antidepressants, opioid and nonsteroidal analgesics, anticonvulsants, antipsychotics, antiparkinsonian agents, skeletal muscle relaxants, antihistamines, anticholinergic medications, and hypoglycemic agents. Additional studies of medication impact on sedation, sleep latency, and psychomotor function, as well as the role of alcohol, are also discussed. Psychotropic agents and those with central nervous system side effects were associated with measures of impaired driving performance. It is difficult to determine if such associations are actually a result of medication use or the medical diagnosis itself. Regardless, clinicians should be aware of the increased risk of impaired driving with specific classes of medications, educate their patients, and/or consider safer alternatives.

  6. The effect of maternal dietary diversity on infant outcome of Pregnant ...

    African Journals Online (AJOL)

    The effect of maternal dietary diversity on infant outcome of Pregnant women. ... East African Journal of Public Health ... can serve as useful predictive indicator of maternal nutrition during pregnancy and the likelihood of delivering LBW babies.

  7. The Effect on Teenage Risky Driving of Feedback From a Safety Monitoring System: A Randomized Controlled Trial

    Science.gov (United States)

    Bingham, C. Raymond; Ouimet, Marie Claude; Pradhan, Anuj; Chen, Rusan; Barretto, Andrea; Shope, Jean

    2012-01-01

    Purpose Teenage risky driving may be due to teenagers not knowing what is risky, preferring risk, or the lack of consequences. Elevated gravitational-force (g-force) events, caused mainly by hard braking and sharp turns, provide a valid measure of risky driving and are the target of interventions using in-vehicle data recording and feedback devices. The effect of two forms of feedback about risky driving events to teenagers only or to teenagers and their parents was tested in a randomized controlled trial. Methods Ninety parent-teen dyads were randomized to one of two groups: (1) immediate feedback to teens (Lights Only); or (2) immediate feedback to teens plus family access to event videos and ranking of the teen relative to other teenage drivers (Lights Plus). Participants’ vehicles were instrumented with data recording devices and events exceeding 0.5 g were assessed for two weeks of baseline and 13 weeks of feedback. Results Growth analysis with random slopes yielded a significant decrease in event rates for the Lights Plus group (slope = −.11, p teenagers did not. Implications and Contribution Reducing elevated g-force events due to hard stops and sharp turns could reduce crash rates among novice teenage drivers. Using materials from the DriveCam For Families Program we found that feedback to both teens and parents significantly reduced rates, while feedback only to teens did not. PMID:23375825

  8. The effects of a single session of spinal manipulation on strength and cortical drive in athletes

    DEFF Research Database (Denmark)

    Christiansen, Thomas Lykke; Niazi, Imran Khan; Holt, Kelly

    2018-01-01

    PURPOSE: The primary purpose of this study was to investigate whether a single session of spinal manipulation (SM) increases strength and cortical drive in the lower limb (soleus muscle) of elite Taekwondo athletes. METHODS: Soleus-evoked V-waves, H-reflex and maximum voluntary contraction (MVC) ...

  9. Use of mobile phones while driving : effects on road safety : a literature review.

    NARCIS (Netherlands)

    Dragutinovic, N. & Twisk, D.A.M.

    2006-01-01

    The use of mobile phones while driving has become a road safety concern and has been the focus of various behavioural studies. This literature review analyses studies published in the period 1999-2005, and include simulator studies, closed-track studies and studies on the real road. Although studies

  10. Effects of mood induction via music on cardiovascular measures of negative emotion during simulated driving

    NARCIS (Netherlands)

    Fairclough, S.H.; Zwaag, van der M.D.; Spiridon, E.; Westerink, J.H.D.M.

    2014-01-01

    A study was conducted to investigate the potential of mood induction via music to influence cardiovascular correlates of negative emotions experience during driving behaviour. One hundred participants were randomly assigned to one of five groups, four of whom experienced different categories of

  11. Effects of in-car support on mental workload and driving performance of older drivers

    NARCIS (Netherlands)

    Davidse, R.J.; Hagenzieker, M.; van Wolffelaar, P.C.; Brouwer, W.H.

    Objective: This study examined the extent to which driving performance of 10 older (70-88 years old) and 30 younger participants (30-50 years old) improves as a result of support by a driver assistance system. Background: Various studies have indicated that advanced driver assistance systems (ADAS)

  12. Linking roadside communication and intelligent cruise control ; effects on driving behaviour

    NARCIS (Netherlands)

    Hogema, J.H.; Horst, A.R.A. van der; Janssen, W.H.

    1995-01-01

    This paper describes a driving simulator experiment in which an Intelligenr Cruise Control (ICC) was combined with short-range communication (SRC) with the road side. This offers the possibility to obtain in-car preview information about relevant conditions on the road ahead. ICCs studied varied in

  13. Current challenges in autonomous driving

    Science.gov (United States)

    Barabás, I.; Todoruţ, A.; Cordoş, N.; Molea, A.

    2017-10-01

    Nowadays the automotive industry makes a quantum shift to a future, where the driver will have smaller and smaller role in driving his or her vehicle ending up being totally excluded. In this paper, we have investigated the different levels of driving automatization, the prospective effects of these new technologies on the environment and traffic safety, the importance of regulations and their current state, the moral aspects of introducing these technologies and the possible scenarios of deploying the autonomous vehicles. We have found that the self-driving technologies are facing many challenges: a) They must make decisions faster in very diverse conditions which can include many moral dilemmas as well; b) They have an important potential in reducing the environmental pollution by optimizing their routes, driving styles by communicating with other vehicles, infrastructures and their environment; c) There is a considerable gap between the self-drive technology level and the current regulations; fortunately, this gap shows a continuously decreasing trend; d) In case of many types of imminent accidents management there are many concerns about the ability of making the right decision. Considering that this field has an extraordinary speed of development, our study is up to date at the submission deadline. Self-driving technologies become increasingly sophisticated and technically accessible, and in some cases, they can be deployed for commercial vehicles as well. According to the current stage of research and development, it is still unclear how the self-driving technologies will be able to handle extreme and unexpected events including their moral aspects. Since most of the traffic accidents are caused by human error or omission, it is expected that the emergence of the autonomous technologies will reduce these accidents in their number and gravity, but the very few currently available test results have not been able to scientifically underpin this issue yet. The

  14. Marijuana and actual driving performance

    Science.gov (United States)

    1993-11-01

    This report concerns the effects of marijuana smoking on actual driving performance. It presents the results of one pilot and three actual driving studies. The pilot study's major purpose was to establish the THC dose current marijuana users smoke to...

  15. Trust and contact in diverse neighbourhoods: An interplay of four ethnicity effects.

    Science.gov (United States)

    Tolsma, J; van der Meer, T W G

    2018-07-01

    Ethnically diverse neighbourhoods are generally less cohesive. A negative relationship between neighbourhood diversity and social cohesion is, however, neither a necessary nor a sufficient condition to conclude that neighbourhood diversity erodes intra-neighbourhood cohesion. This contribution shows - by using data collected during the second wave of the NEtherlands Longitudinal Lifecourse Study (NELLS) - that: (1) members of ethnic minority groups are more likely to report having contact with and trust their immediate neighbours than natives (ego ethnicity effect); (2) minority group residents are less likely to be contacted and trusted by their neighbours (alter ethnicity effect) and (3) all ethnic groups prefer to mix with coethnics (dyad ethnicity effect). Once we control for these three ethnic composition effects at the ego, alter and dyad-level, neighbourhood ethnic diversity is no longer related to less contact between neighbours. Previously identified negative relationships between neighbourhood diversity and cohesion should therefore be re-evaluated, as they may be the consequence of ethnic composition effects instead of a true neighbourhood diversity effect. Copyright © 2018. Published by Elsevier Inc.

  16. Phytoplankton Diversity Effects on Community Biomass and Stability along Nutrient Gradients in a Eutrophic Lake

    Directory of Open Access Journals (Sweden)

    Wang Tian

    2017-01-01

    Full Text Available The relationship between biodiversity and ecosystem functioning is a central issue in ecology, but how this relationship is affected by nutrient stress is still unknown. In this study, we analyzed the phytoplankton diversity effects on community biomass and stability along nutrient gradients in an artificial eutrophic lake. Four nutrient gradients, varying from slightly eutrophic to highly eutrophic states, were designed by adjusting the amount of polluted water that flowed into the lake. Mean phytoplankton biomass, species richness, and Shannon diversity index all showed significant differences among the four nutrient gradients. Phytoplankton community biomass was correlated with diversity (both species richness and Shannon diversity index, varying from positive to negative along the nutrient gradients. The influence of phytoplankton species richness on resource use efficiency (RUE also changed from positive to negative along the nutrient gradients. However, the influence of phytoplankton Shannon diversity on RUE was not significant. Both phytoplankton species richness and Shannon diversity had a negative influence on community turnover (measured as community dissimilarity, i.e., a positive diversity–stability relationship. Furthermore, phytoplankton spatial stability decreased along the nutrient gradients in the lake. With increasing nutrient concentrations, the variability (standard deviation of phytoplankton community biomass increased more rapidly than the average total biomass. Results in this study will be helpful in understanding the phytoplankton diversity effects on ecosystem functioning and how these effects are influenced by nutrient conditions in aquatic ecosystems.

  17. Effects of alcohol on attention orienting and dual-task performance during simulated driving: an event-related potential study.

    Science.gov (United States)

    Wester, Anne E; Verster, Joris C; Volkerts, Edmund R; Böcker, Koen B E; Kenemans, J Leon

    2010-09-01

    Driving is a complex task and is susceptible to inattention and distraction. Moreover, alcohol has a detrimental effect on driving performance, possibly due to alcohol-induced attention deficits. The aim of the present study was to assess the effects of alcohol on simulated driving performance and attention orienting and allocation, as assessed by event-related potentials (ERPs). Thirty-two participants completed two test runs in the Divided Attention Steering Simulator (DASS) with blood alcohol concentrations (BACs) of 0.00%, 0.02%, 0.05%, 0.08% and 0.10%. Sixteen participants performed the second DASS test run with a passive auditory oddball to assess alcohol effects on involuntary attention shifting. Sixteen other participants performed the second DASS test run with an active auditory oddball to assess alcohol effects on dual-task performance and active attention allocation. Dose-dependent impairments were found for reaction times, the number of misses and steering error, even more so in dual-task conditions, especially in the active oddball group. ERP amplitudes to novel irrelevant events were also attenuated in a dose-dependent manner. The P3b amplitude to deviant target stimuli decreased with blood alcohol concentration only in the dual-task condition. It is concluded that alcohol increases distractibility and interference from secondary task stimuli, as well as reduces attentional capacity and dual-task integrality.

  18. The perceived influence of diversity factors on effective strategy implementation in a higher education institution

    Directory of Open Access Journals (Sweden)

    K. Strydom

    2018-04-01

    Full Text Available Managing diversity is one of the major challenges in higher education institutions in South Africa. Additionally, effective strategy implementation is vital for an institution to be successful and sustainable. Questionnaires were distributed to the management of Walter Sisulu University, South Africa, to investigate the relationship between diversity factors and effective strategy implementation. The questionnaires interrogated the effect of the acculturation process, the degree of structural integration, the degree of informal integration, institutional bias and intergroup conflict, and how these factors influence strategy implementation. Structural equation modelling (SEM was employed as the statistical tool to confirm the hypothetical model. Results of this study revealed that there is no statistically significant relationship between diversity and strategy implementation at the institution, and imply that diversity among staff do not impact on the successful achievement of strategic objectives in the institution. The findings of the study are contrary to empirical evidence by other studies. Keywords: Education, Sociology, Political science, Psychology

  19. DAC to Mitigate the Effect of Periodic Disturbances on Drive Train using Collective Pitch for Variable Speed Wind Turbine

    DEFF Research Database (Denmark)

    Imran, Raja Muhammad; Hussain, Dil Muhammad Akbar; Soltani, Mohsen

    2015-01-01

    scheme to mitigate the effect of 3p flicker on drive train. 5MW wind turbine of the National Renewable Laboratories (NREL) is used as research object and results are simulated in MATLAB/Simulink. We designed the controller based on linearized model of the wind turbine generated for above rated wind speed...... and then tested its performance on the nonlinear model of wind turbine. We have shown a comparison of the results for proportional-integral(PI) and proposed DAC controller tested on nonlinear model of wind turbine. Result shows that our proposed controller shows better mitigation of flicker generated due to 3p......DAC is a linear control technique used to mitigate the effect of disturbance on the plant. It is a superposition of full state feedback and disturbance feedback. This paper presents a control technique based on Disturbance Accommodation Control (DAC) to reduce fatigue on drive train generated...

  20. Bio-diversity: an effective safety net against environmental pollution

    International Nuclear Information System (INIS)

    Swaminathan, M.S.

    2003-01-01

    Biodiversity is the feedstock for the biotechnology industry. Hence, the conservation, enhancement and sustainable and equitable use of biodiversity should be accorded high priority in all national environment protection programmes. Lichens serve as useful indicators of environmental health. Similarly, several blue green algae help to sequester salt from water. There is need for the more widespread use of such biomonitoring and bioremediation agents. Bioprospecting research designed to identify novel metabolites must be rooted in the principle of equity in sharing benefits with the holders of traditional knowledge. There is need for greater vigil against alien invasive species, since with growing world trade in food grains and other agricultural commodities, there is an increasing possibility of introducing new pests, weeds and harmful micro-organisms. Finally, biological scientists should place emphasis on their ethical responsibility for the consequences of their research, since otherwise bioterrorism could become a major threat to human security. - The age of biological diversity serves as an impetus for the future of biotechnology

  1. Bio-diversity: an effective safety net against environmental pollution

    Energy Technology Data Exchange (ETDEWEB)

    Swaminathan, M.S

    2003-12-01

    Biodiversity is the feedstock for the biotechnology industry. Hence, the conservation, enhancement and sustainable and equitable use of biodiversity should be accorded high priority in all national environment protection programmes. Lichens serve as useful indicators of environmental health. Similarly, several blue green algae help to sequester salt from water. There is need for the more widespread use of such biomonitoring and bioremediation agents. Bioprospecting research designed to identify novel metabolites must be rooted in the principle of equity in sharing benefits with the holders of traditional knowledge. There is need for greater vigil against alien invasive species, since with growing world trade in food grains and other agricultural commodities, there is an increasing possibility of introducing new pests, weeds and harmful micro-organisms. Finally, biological scientists should place emphasis on their ethical responsibility for the consequences of their research, since otherwise bioterrorism could become a major threat to human security. - The age of biological diversity serves as an impetus for the future of biotechnology.

  2. Impaired Driving

    Science.gov (United States)

    ... Get the Facts What Works: Strategies to Increase Car Seat and Booster Seat ... narcotics. 3 That’s one percent of the 111 million self-reported episodes of alcohol-impaired driving among U.S. ...

  3. Real-world effects of using a phone while driving on lateral and longitudinal control of vehicles.

    Science.gov (United States)

    Dozza, Marco; Flannagan, Carol A C; Sayer, James R

    2015-12-01

    Technologies able to augment human communication, such as smartphones, are increasingly present during all daily activities. Their use while driving, in particular, is of great potential concern, because of the high risk that distraction poses during this activity. Current countermeasures to distraction from phone use are considerably different across countries and not always widely accepted/adopted by the drivers. This study utilized naturalistic driving data collected from 108 drivers in the Integrated Vehicle-Based Safety Systems (IVBSS) program in 2009 and 2010 to assess the extent to which using a phone changes lateral or longitudinal control of a vehicle. The IVBSS study included drivers from three age groups: 20–30 (younger), 40–50 (middle-aged), and 60–70 (older). Results from this study show that younger drivers are more likely to use a phone while driving than older and middle-aged drivers. Furthermore, younger drivers exhibited smaller safety margins while using a phone. Nevertheless, younger drivers did not experience more severe lateral/longitudinal threats than older and middle-aged drivers, probably because of faster reaction times. While manipulating the phone (i.e., dialing, texting), drivers exhibited larger lateral safety margins and experienced less severe lateral threats than while conversing on the phone. Finally, longitudinal threats were more critical soon after phone interaction, suggesting that drivers terminate phone interactions when driving becomes more demanding. These findings suggest that drivers are aware of the potential negative effect of phone use on their safety. This awareness guides their decision to engage/disengage in phone use and to increase safety margins (self-regulation). This compensatory behavior may be a natural countermeasure to distraction that is hard to measure in controlled studies. Practical Applications: Intelligent systems able to amplify this natural compensatory behavior may become a widely accepted

  4. A New Cost-Effective Multi-Drive Solution based on a Two-Stage Direct Power Electronic Conversion Topology

    DEFF Research Database (Denmark)

    Klumpner, Christian; Blaabjerg, Frede

    2002-01-01

    of a protection circuit involving twelve diodes with full voltage/current ratings used only during faulty situations, makes this topology not so attractive. Lately, two stage Direct Power Electronic Conversion (DPEC) topologies have been proposed, providing similar functionality as a matrix converter but allowing...... shared by many loads, making this topology more cost effective. The functionality of the proposed two-stage multi-drive direct power electronic conversion topology is validated by experiments on a realistic laboratory prototype....

  5. Effect of resonant-to-bulk electron momentum transfer on the efficiency of electron-cyclotron current-drive

    International Nuclear Information System (INIS)

    Matsuda, Y.; Smith, G.R.; Cohen, R.H.

    1989-01-01

    Efficiency of current drive by electron cyclotron waves is investigated numerically by a bounce-averaged Fokker-Planck code to ellucidate the effects of momentum transfer from resonant to bulk-electrons, finite bulk temperature relative to the energy of resonant electrons, and trapped electrons. Comparisons are made with existing theories to assess their validity and quantitative difference between theory and code results. Difference of nearly a factor of 2 was found in efficiency between some theory and code results. (author)

  6. Effect of Aerobic Exercise Training on Ventilatory Efficiency and Respiratory Drive in Obese Subjects.

    Science.gov (United States)

    Chlif, Mehdi; Chaouachi, Anis; Ahmaidi, Said

    2017-07-01

    Obese patients show a decline in exercise capacity and diverse degrees of dyspnea in association with mechanical abnormalities, increased ventilatory requirements secondary to the increased metabolic load, and a greater work of breathing. Consequently, obese patients may be particularly predisposed to the development of respiratory muscle fatigue during exercise. The aim of this study was to assess inspiratory muscle performance during incremental exercise in 19 obese male subjects (body mass index 41 ± 6 kg/m 2 ) after aerobic exercise training using the noninvasive, inspiratory muscle tension-time index (T T0.1 ). Measurements performed included anthropometric parameters, lung function assessed by spirometry, rate of perceived breathlessness with the modified Borg dyspnea scale (0-10), breathing pattern, maximal exercise capacity, and inspiratory muscle performance with a breath-by-breath automated exercise metabolic system during an incremental exercise test. T T0.1 was calculated using the equation, T T0.1 = P 0.1 /P Imax × T I /T tot (where P 0.1 represents mouth occlusion pressure, P Imax is maximal inspiratory pressure, and T I /T tot is the duty cycle). At rest, there was no statistically significant difference for spirometric parameters and cardiorespiratory parameters between pre- and post-training. At maximal exercise, the minute ventilation, the rate of exchange ratio, the rate of perceived breathlessness, and the respiratory muscle performance parameters were not significantly different pre- and post-training; in contrast, tidal volume ( P = .037, effect size = 1.51), breathing frequency ( P = .049, effect size = 0.97), power output ( P = .048, effect size = 0.79), peak oxygen uptake ( P = .02, effect size = 0.92) were significantly higher after training. At comparable work load, training induces lower minute ventilation, mouth occlusion pressure, ratio of occlusion pressure to maximal inspiratory pressure, T T0.1 , and rate of perceived

  7. EFFECT OF ENVIRONMENTAL DEGRADATION ON ANIMAL DIVERSITY IN BALI, INDONESSIA

    Directory of Open Access Journals (Sweden)

    I Wayan Kasa

    2015-11-01

    Full Text Available Bali is a small beautiful tropical island of Indonesia archipelago, lies between the continent of Asia and Australia, as well as the Indian and Pacific Ocean. As a tropical archipelago, many kinds of biodiversity can be found. The island of Bali in particular, there are typical animal diversity that could not be investigated beyond such island, such as, Bali cattle, Bali dog, Bali starling and others. As time goes on, the existance of such biodiversity decreases in both body weight and population number. Both global warming/climate change and land use change are the main factors affecting such phenomenon. This study has been conducted by employing field observation as well as literature study. It was found that, the quality of purebred Bali cattle species decreases genetically that could be notified of smaller bodysize for both male and female. Land use change of agriculture activity to the hotels, house of living, roads and other infrastructures are the main factors for Bali cattle existence. For typical famous bird of Balistarling, the problem is because of deforestation which cause natural habitat loss, due to land use change for agricultural activity and house building by local people. In case of Bali dog, the mad dog of rabies is just introduce and spreading over Bali island, whichis formerly the island of Bali has been recognised as free zone area of the rabies. As consequence, suffering dogs must be eliminated by  mass killing cause decrease total number of such poor dog. Overall, it could be concluded that environmental degradations of land use change, deforestation and desease are the main causes of biodiversity decreasing number of the Bali cattle, Bali white starling and Bali dog respectively, beside global warming/climate change natural disaster. Key words: Environment, Bali cattle, Bali starling, Bali dog, Bali island.

  8. EFFECT OF ENVIRONMENTAL DEGRADATION ON ANIMAL DIVERSITY IN BALI, INDONESIA

    Directory of Open Access Journals (Sweden)

    I Waya Kasa

    2015-09-01

    Full Text Available Bali is a small beautiful tropical island of Indonesia archipelago lies betweens the continent of Asia and Australia as well as the Indian and Pacific Ocean. As a tropical archipelago, of course, many kinds of biodiversity can be found over there. In the island of Bali in particular, there are typical animal diversity that could not be investigated beyond such island, such as, Bali cattle, Bali dog, Bali white starling and others. As time goes on, the existance of such biodiversity decreases in both quality and quantity. Both global warming/climate change and land use change are the main factors affecting such phenomenon. This study has been conducted by employing field observation as well as literature study. It was found that, the quality of purebred Bali cattle species decreases genetically that could be notified of smaller bodysize for both male and female. Land use change of agriculture activity to the hotels, house of living, roads and other infrastructures are the main factors for Bali cattle existancy. For typical famous bird of white starling, the problem is because of deforestation which cause natural habitat loss, due to land use change for agricultural activity and house building by local people. In case of Bali dog, the mad dog of rabies is just introduce and spreading over Bali island, whichis formerly the island of Bali has been recognised as free zone area of the rabies. As consequency, suffering dogs must be eliminated by a mass killing cause decrease total number of such poor dog. Overall, it could be concluded that environmental degradations of land use change, deforestation and desease are the main causes of biodiversity decreasing number of the Bali cattle, Bali white starling and Bali dog respectively, beside global warming/climate change natural disaster.

  9. Microbial diversity and structure are drivers of the biological barrier effect against Listeria monocytogenes in soil.

    Science.gov (United States)

    Vivant, Anne-Laure; Garmyn, Dominique; Maron, Pierre-Alain; Nowak, Virginie; Piveteau, Pascal

    2013-01-01

    Understanding the ecology of pathogenic organisms is important in order to monitor their transmission in the environment and the related health hazards. We investigated the relationship between soil microbial diversity and the barrier effect against Listeria monocytogenes invasion. By using a dilution-to-extinction approach, we analysed the consequence of eroding microbial diversity on L. monocytogenes population dynamics under standardised conditions of abiotic parameters and microbial abundance in soil microcosms. We demonstrated that highly diverse soil microbial communities act as a biological barrier against L. monocytogenes invasion and that phylogenetic composition of the community also has to be considered. This suggests that erosion of diversity may have damaging effects regarding circulation of pathogenic microorganisms in the environment.

  10. Analyzing the Long Term Cohesive Effect of Sector Specific Driving Forces.

    Directory of Open Access Journals (Sweden)

    Yonatan Berman

    Full Text Available Financial markets are partially composed of sectors dominated by external driving forces, such as commodity prices, infrastructure and other indices. We characterize the statistical properties of such sectors and present a novel model for the coupling of the stock prices and their dominating driving forces, inspired by mean reverting stochastic processes. Using the model we were able to explain the market sectors' long term behavior and estimate the coupling strength between stocks in financial markets and the sector specific driving forces. Notably, the analysis was successfully applied to the shipping market, in which the Baltic dry index (BDI, an assessment of the price of transporting the major raw materials by sea, influences the shipping financial market. We also present the analysis of other sectors-the gold mining market and the food production market, for which the model was also successfully applied. The model can serve as a general tool for characterizing the coupling between external forces and affected financial variables and therefore for estimating the risk in sectors and their vulnerability to external stress.

  11. Effect of the relative phase of the driving sources on heating of dual frequency capacitive discharges

    Science.gov (United States)

    Ziegler, Dennis; Trieschmann, Jan; Mussenbrock, Thomas; Brinkmann, Ralf Peter

    2009-10-01

    The influence of the relative phase of the driving voltages on heating in asymmetric dual frequency capacitive discharges is investigated. Basis of the analysis is a recently published global model [1] extended by the possibility to freely adjust the phase angles between the driving voltages. In recent publications it was reported that nonlinear electron resonance heating (NERH) drastically enhances dissipation at moments of sheath collapse due to plasma series resonance (PSR) excitation [2]. This work shows that depending on the relative phase of the driving voltages, the total number and exact moments of sheath collapse can be influenced. In case of a collapse directly being followed by a second collapse ("double collapse") a substantial increase in dissipated power, well above the reported growth due to a single PSR excitation event per period, can be observed.[4pt] [1] D.,iegler, T.,ussenbrock, and R.,. Brinkmann, Phys. Plasmas 16, 023503 (2009)[0pt] [2] T.,ussenbrock, R.,. Brinkmann, M.,. Lieberman, A.,. Lichtenberg, and E. Kawamura, Phys. Rev. Lett. 101, 085004 (2008)

  12. The effects of intranasal esketamine (84 mg) and oral mirtazapine (30 mg) on on-road driving performance : a double-blind, placebo-controlled study

    NARCIS (Netherlands)

    van de Loo, Aurora J A E; Bervoets, Adriana C; Mooren, Loes; Bouwmeester, Noor H; Garssen, Johan; Zuiker, Rob; van Amerongen, Guido; van Gerven, Joop; Singh, Jaskaran; der Ark, Peter Van; Fedgchin, Maggie; Morrison, Randall; Wajs, Ewa; Verster, Joris

    2017-01-01

    RATIONALE: The purpose of this study is to evaluate the single dose effect of intranasal esketamine (84 mg) compared to placebo on on-road driving performance. Mirtazapine (oral, 30 mg) was used as a positive control, as this antidepressant drug is known to negatively affect driving performance.

  13. Effects of drive current rise-time and initial load density distribution on Z-pinch characteristics

    Institute of Scientific and Technical Information of China (English)

    Duan Yao-Yong; Guo Yong-Hui; Wang Wen-Sheng; Qiu Ai-Ci

    2005-01-01

    A two-dimensional, three-temperature radiation magneto-hydrodynamics model is applied to the investigation of evolutional trends in x-ray radiation power, energy, peak plasma temperature and density as functions of drive current rise-time and initial load density distribution by using the typical experimental parameters of tungsten wire-array Z-pinch on the Qiangguang-Ⅰ generator. The numerical results show that as the drive current rise-time is shortened, x-ray radiation peak power, energy, peak plasma density and peak ion temperature increase approximately linearly, but among them the x-ray radiation peak power increases more quickly. As the initial plasma density distribution in the radial direction becomes gradually flattened, the peak radiation power and the peak ion-temperature almost exponentially increase, while the radiation energy and the peak plasma density change only a little. The main effect of shortening drive current rise-time is to enhance compression of plasma, and the effect of flattening initial load density distribution in the radial direction is to raise the plasma temperature. Both of the approaches elevate the x-ray peak radiation power.

  14. effect of habitat fragmentation on diversity and abundance of nesting

    African Journals Online (AJOL)

    cw

    Department of Zoology and Wildlife Conservation, University of Dar es ... Keywords: fragmentation, nesting birds, thickets, campus of the University of Dar es ... 43(1), 2017 ..... Yale University Press, ... bird species in urban parks: Effects of park.

  15. Parent Involvement in Novice Teen Driving: Rationale, Evidence of Effects, and Potential for Enhancing Graduated Driver Licensing Effectiveness

    OpenAIRE

    Simons-Morton, Bruce

    2007-01-01

    Motor vehicle crash rates are highly elevated immediately after licensure and then decline gradually over a period of years. Young age, risk taking, and inexperience contribute to the problem, but inexperience is particularly important early on. Driving is like other complex, skilled behaviors in which subtle improvements in perception and judgment develop gradually over a period of years. After all, safe driving is more a matter of attention and perception than physical management of the veh...

  16. Effects of Conservation Agriculture and Fertilization on Soil Microbial Diversity and Activity

    Directory of Open Access Journals (Sweden)

    Johan Habig

    2015-07-01

    Full Text Available Soil microbial communities perform critical functions in ecosystem processes. These functions can be used to assess the impact of agricultural practices on sustainable crop production. In this five-year study, the effect of various agricultural practices on soil microbial diversity and activity was investigated in a summer rainfall area under South African dryland conditions. Microbial diversity and activity were measured in the 0–15 cm layer of a field trial consisting of two fertilizer levels, three cropping systems, and two tillage systems. Using the Shannon–Weaver and Evenness diversity indices, soil microbial species richness and abundance were measured. Microbial enzymatic activities: β-glucosidase, phosphatase and urease, were used to evaluate ecosystem functioning. Cluster analysis revealed a shift in soil microbial community diversity and activity over time. Microbial diversity and activity were higher under no-till than conventional tillage. Fertilizer levels seemed to play a minor role in determining microbial diversity and activity, whereas the cropping systems played a more important role in determining the activity of soil microbial communities. Conservation agriculture yielded the highest soil microbial diversity and activity in diversified cropping systems under no-till.

  17. Effective Multicultural Supervision for a Culturally Diverse Country

    Science.gov (United States)

    Smith, Amanda

    2016-01-01

    Living in a country based on the "salad bowl" of cultures philosophy, it is necessary for mental health professionals to be competent in providing effective counseling to heterogeneous clientele. Multicultural counseling ensures that professional counselors will deliver services matching the clients' needs, resulting in valuable…

  18. PNT effect on diversity of Rhizobia associated with Sesbania sesban

    International Nuclear Information System (INIS)

    Sacko, O.; Yattara, I. I.; Diop, T.; Neyra, M.

    2009-01-01

    Tilemsi rock phosphate (TRP) of Mail is one of the best rock phosphates in West Africa. But it is less used because of its insoluble form. The main objective of this study is to investigate its effect on rhizobia living under a multipurpose leguminous tree. The substrates was Senega lean soil which was less poor in phosphorus and not sterilized. (Author)

  19. Driving things

    DEFF Research Database (Denmark)

    Nevile, Maurice Richard

    2015-01-01

    I explore how participants organise involvement with objects brought into the car, relative to the demands of driving and social activity. Objects in cars commonly include phones or other technologies, food, body care products, texts, clothing, bags and carry items, toys, and even animals...... 2004, Haddington et al. 2012). I focus here especially on how the practical and interactional work of locating, seeing, placing, handling, hearing, and relinquishing, is ordered and accomplished relative to the emerging and contingent demands of both driving and social participation......, such that involvement with objects is constituted as secondary to driving in a multiactivity setting (e.g. Haddington et al. 2014). We see how events with, for, of, and even by objects can occur as predictable, planned and even designed for (e.g. changing glasses, applying body lotion), or might be unexpected...

  20. Environmental Effects of Driving Automobiles in the University of Malaya Campus: A Pilot Study

    Directory of Open Access Journals (Sweden)

    S.Y. Kong

    2009-12-01

    Full Text Available With the increase of human population there has been an evident increase in per capita automobile use and ownership, significantly to a point that almost every urban university campus faces serious challenges from the heavy traffic movement as well as the associated parking shortages. Multiple factors, including lack of land for new parking lots, high cost of building parking structures and the desire to preserve the air quality and campus green spaces are leading many educational institutions towards a new vision based upon expanded transit access, better bicycle and pedestrian facilities and financial incentives for students and staff to drive less. (Toor and Havlick, 2004 This is in stark contrast to the traditional approach to campus transportation planning of the University of Malaya (UM, Kuala Lumpur, Malaysia that allows students, staff and visitors to drive in the campus. The objective of this study is to investigate the related issues and environmental impact of allowing automobile driving in the campus. Studies will also be done to analyse the relationship between university campus planning and traffic condition. Air quality and noise pollution data of 3 selected sites in the campus will be recorded. Subsequently, the air pollutant index and noise pollution level will be identified and data analyses will be done on the data samples. Simultaneously, a survey questionnaire will be conducted to gauge the student’s attitude and degree of awareness with air and noise pollution in the campus. This pilot study reveals that the increasing use of automobiles within the campus has a negative impact on local environment and the quality of life in campus

  1. Effects of a blue light-filtering intraocular lens on driving safety in glare conditions.

    Science.gov (United States)

    Gray, Rob; Hill, Warren; Neuman, Brooke; Houtman, Diane; Potvin, Richard

    2012-05-01

    To evaluate whether the previously established benefit of blue light-filtering intraocular lenses (IOLs) when driving in glare conditions is maintained in patients previously implanted with a blue light-filtering toric IOL. Department of Applied Psychology, Arizona State University, Mesa, Arizona, USA. Comparative case series. The study comprised patients with a blue light-filtering toric IOL (test IOL) or an ultraviolet (UV)-only filtering nontoric IOL (control IOL). All patients had good visual acuity and a valid driver's license. While wearing best spherocylindrical correction, patients performed left-turn maneuvers in front of oncoming traffic in a driving simulator. The safety margin was defined as the time to collision less the time taken to turn at an intersection with oncoming traffic. Measures were repeated with a glare source simulating low-angle sun conditions (daytime driving). Of the 33 evaluable patients, 18 had a test IOL and 15 had a control IOL. In the presence of glare, patients with test IOLs had significantly greater safety margins (mean 2.676 seconds ± 0.438 [SD]) than patients with control IOLs (mean 2.179 ± 0.343 seconds) and significantly lower glare susceptibility (P<.05). In no-glare and glare conditions, patients with test IOLs had significantly lower glare susceptibility than patients with control IOLs. The blue light-filtering toric IOL produced a significantly greater reduction in glare disability than the UV-only filtering nontoric IOL and increased the ability of drivers to safely execute left turns in low-sun conditions. Dr. Houtman is an employee of Alcon Laboratories, Inc. No other author has a financial or proprietary interest in any material or method mentioned. Copyright © 2012 ASCRS and ESCRS. Published by Elsevier Inc. All rights reserved.

  2. Physical driving force of actomyosin motility based on the hydration effect.

    Science.gov (United States)

    Suzuki, Makoto; Mogami, George; Ohsugi, Hideyuki; Watanabe, Takahiro; Matubayasi, Nobuyuki

    2017-12-01

    We propose a driving force hypothesis based on previous thermodynamics, kinetics and structural data as well as additional experiments and calculations presented here on water-related phenomena in the actomyosin systems. Although Szent-Györgyi pointed out the importance of water in muscle contraction in 1951, few studies have focused on the water science of muscle because of the difficulty of analyzing hydration properties of the muscle proteins, actin, and myosin. The thermodynamics and energetics of muscle contraction are linked to the water-mediated regulation of protein-ligand and protein-protein interactions along with structural changes in protein molecules. In this study, we assume the following two points: (1) the periodic electric field distribution along an actin filament (F-actin) is unidirectionally modified upon binding of myosin subfragment 1 (M or myosin S1) with ADP and inorganic phosphate Pi (M.ADP.Pi complex) and (2) the solvation free energy of myosin S1 depends on the external electric field strength and the solvation free energy of myosin S1 in close proximity to F-actin can become the potential force to drive myosin S1 along F-actin. The first assumption is supported by integration of experimental reports. The second assumption is supported by model calculations utilizing molecular dynamics (MD) simulation to determine solvation free energies of a small organic molecule and two small proteins. MD simulations utilize the energy representation method (ER) and the roughly proportional relationship between the solvation free energy and the solvent-accessible surface area (SASA) of the protein. The estimated driving force acting on myosin S1 is as high as several piconewtons (pN), which is consistent with the experimentally observed force. © 2017 Wiley Periodicals, Inc.

  3. Turbulent current drive mechanisms

    Science.gov (United States)

    McDevitt, Christopher J.; Tang, Xian-Zhu; Guo, Zehua

    2017-08-01

    Mechanisms through which plasma microturbulence can drive a mean electron plasma current are derived. The efficiency through which these turbulent contributions can drive deviations from neoclassical predictions of the electron current profile is computed by employing a linearized Coulomb collision operator. It is found that a non-diffusive contribution to the electron momentum flux as well as an anomalous electron-ion momentum exchange term provide the most efficient means through which turbulence can modify the mean electron current for the cases considered. Such turbulent contributions appear as an effective EMF within Ohm's law and hence provide an ideal means for driving deviations from neoclassical predictions.

  4. Effect of mass loss on the driving of g-modes in B supergiant stars

    Energy Technology Data Exchange (ETDEWEB)

    Godart, Melanie; Noels, Arlette [Institut d' Astrophysique et de Geophysique, Liege (Belgium); Dupret, Marc-Antoine [Observatoire de Paris-Meudon, LESIA (France)], E-mail: Helanie.Godart@ulg.ac.be, E-mail: Arlette.Noels@ulg.ac.be, E-mail: ma.dupret@obspm.fr

    2008-10-15

    MOST has detected p and g-modes in the B supergiant star HD163899. Saio et al. (2006) have explained the driving of g-modes in a post main sequence star by the presence of a convective shell which prevents some modes from entering the damping radiative core. We show that this scenario depends on the evolution of the star, with or without mass loss. If the mass loss rate is high enough, the convective shell disappears and all the g-modes are stable.

  5. Effect of alcohol and divided attention task on simulated driving performance of young drivers

    OpenAIRE

    FREYDIER , Chloé; BERTHELON , Catherine; Bastien-Toniazzo , Mireille; GINEYT , Guy

    2013-01-01

    The aim of this study is to evaluate driving impairment linked to divided attention task and alcohol and determinate if it is higher for novice drivers compared to more experienced drivers. Sixteen novice drivers and sixteen experienced drivers participated in three experimental sessions corresponding to blood alcohol concentration [BAC] of 0.0 g/L, 0.2 g/L and 0.5 g/L. They performed a divided attention task [car-following task combined with a number parity identification task], and their re...

  6. The effect of nabilone on neuropsychological functions related to driving ability: an extended case series.

    Science.gov (United States)

    Kurzthaler, Ilsemarie; Bodner, Thomas; Kemmler, Georg; Entner, Tanja; Wissel, Joerg; Berger, Thomas; Fleischhacker, W Wolfgang

    2005-06-01

    The primary goal of this prospective extended case series was to obtain the first data about the potential influence of nabilone intake on driving ability related neuropsychological functions. Six patients were investigated within a placebo controlled, double-blind crossover study of this synthetic cannabinoid (2 mg/day) in patients with multiple sclerosis and spasticity associated pain. Five neuropsychological functions (reaction time, working memory, divided attention, psychomotor speed and mental flexibility) were assessed. No indication was found of a deterioration of any of the five investigated neuropsychological functions during the 4-week treatment period with nabilone. Copyright 2005 John Wiley & Sons, Ltd.

  7. Effect of mass loss on the driving of g-modes in B supergiant stars

    International Nuclear Information System (INIS)

    Godart, Melanie; Noels, Arlette; Dupret, Marc-Antoine

    2008-01-01

    MOST has detected p and g-modes in the B supergiant star HD163899. Saio et al. (2006) have explained the driving of g-modes in a post main sequence star by the presence of a convective shell which prevents some modes from entering the damping radiative core. We show that this scenario depends on the evolution of the star, with or without mass loss. If the mass loss rate is high enough, the convective shell disappears and all the g-modes are stable.

  8. The effects of using a portable music player on simulated driving performance and task-sharing strategies.

    Science.gov (United States)

    Young, Kristie L; Mitsopoulos-Rubens, Eve; Rudin-Brown, Christina M; Lenné, Michael G

    2012-07-01

    This study examined the effects of performing scrollable music selection tasks using a portable music player (iPod Touch™) on simulated driving performance and task-sharing strategies, as evidenced through eye glance behaviour and secondary task performance. A total of 37 drivers (18-48 yrs) completed the PC-based MUARC Driver Distraction Test (DDT) while performing music selection tasks on an iPod Touch. Drivers' eye glance behaviour was examined using faceLAB eye tracking equipment. Results revealed that performing music search tasks while driving increased the amount of time that drivers spent with their eyes off the roadway and decreased their ability to maintain a constant lane position and time headway from a lead vehicle. There was also evidence, however, that drivers attempted to regulate their behaviour when distracted by decreasing their speed and taking a large number of short glances towards the device. Overall, results suggest that performing music search tasks while driving is problematic and steps to prohibit this activity should be taken. Copyright © 2011 Elsevier Ltd and The Ergonomics Society. All rights reserved.

  9. effect of bush burning on herbaceous plant diversity in lagos state

    African Journals Online (AJOL)

    conducted to assess the effect of bush burning on plant species diversity. Three frequently burnt ... also believed to rid the grassland of parasitic insects and to prevent the encroachment of ..... The effect of smoke inhalation on lung function and ...

  10. The effect of aging upon CE and B and W control rod drives

    International Nuclear Information System (INIS)

    Grove, E.; Gunther, W.

    1991-01-01

    Though mechanically different, the control rod drive (CRD) systems used at both Combustion Engineering (CE) and Babcock and Wilcox (B and W) plants position the control rod assemblies (CRA) in the core in response to automatic or manual reactivity control signals. Both systems are also designed to provide a rapid insertion of the CRAs upon a loss of AC power. The CRD system consists of the actual drive mechanisms, power and control, rod position indication, and cooling system components. This aging evaluation included the individual absorber rods, and the fuel assembly and upper internal guide tubes, since failure of these components could preclude the insertion of the control assemblies. Aging and environmental degradation have resulted in system and component failures. Many of these failures caused dropped or slipped rods which adversely affected plant operations by resulting in power reductions, scrams, and safety system actuation. No CRD system failure has ever resulted in the inability to shut down a reactor. However, unplanned, automatic trips challenge the operation of the plants safety systems. Consequently, their occurrence represents a potentially significant increase in plant risk. System and component failures have resulted in four Information Notices during the past decade

  11. Effects of mood induction via music on cardiovascular measures of negative emotion during simulated driving.

    Science.gov (United States)

    Fairclough, Stephen H; van der Zwaag, Marjolein; Spiridon, Elena; Westerink, Joyce

    2014-04-22

    A study was conducted to investigate the potential of mood induction via music to influence cardiovascular correlates of negative emotions experience during driving behaviour. One hundred participants were randomly assigned to one of five groups, four of whom experienced different categories of music: High activation/positive valence (HA/PV), high activation/negative valence (HA/NV), low activation/positive valence (LA/PV) and low activation/negative valence (LA/NV). Following exposure to their respective categories of music, participants were required to complete a simulated driving journey with a fixed time schedule. Negative emotion was induced via exposure to stationary traffic during the simulated route. Cardiovascular reactivity was measured via blood pressure, heart rate and cardiovascular impedance. Subjective self-assessment of anger and mood was also recorded. Results indicated that low activation music, regardless of valence, reduced systolic reactivity during the simulated journey relative to HA/NV music and the control (no music) condition. Self-reported data indicated that participants were not consciously aware of any influence of music on their subjective mood. It is concluded that cardiovascular reactivity to negative mood may be mediated by the emotional properties of music. Copyright © 2014 Elsevier Inc. All rights reserved.

  12. Modelling the Effect of Driving Events on Electrical Vehicle Energy Consumption Using Inertial Sensors in Smartphones

    Directory of Open Access Journals (Sweden)

    David Jiménez

    2018-02-01

    Full Text Available Air pollution and climate change are some of the main problems that humankind is currently facing. The electrification of the transport sector will help to reduce these problems, but one of the major barriers for the massive adoption of electric vehicles is their limited range. The energy consumption in these vehicles is affected, among other variables, by the driving behavior, making range a value that must be personalized to each driver and each type of electric vehicle. In this paper we offer a way to estimate a personalized energy consumption model by the use of the vehicle dynamics and the driving events detected by the use of the smartphone inertial sensors, allowing an easy and non-intrusive manner to predict the correct range for each user. This paper proposes, for the classification of events, a deep neural network (Long-Short Time Memory which has been trained with more than 22,000 car trips, and the application to improve the consumption model taking into account the driver behavior captured across different trips, allowing a personalized prediction. Results and validation in real cases show that errors in the predicted consumption values are halved when abrupt events are considered in the model.

  13. "Presumed fair: Ironic effects of organizational diversity structures": Correction to Kaiser et al. (2013).

    Science.gov (United States)

    2016-06-01

    Reports an error in "Presumed fair: Ironic effects of organizational diversity structures" by Cheryl R. Kaiser, Brenda Major, Ines Jurcevic, Tessa L. Dover, Laura M. Brady and Jenessa R. Shapiro (Journal of Personality and Social Psychology, 2013[Mar], Vol 104[3], 504-519). In the article, a raw data merging error in one racial discrimination claim condition from Experiment 6 inadvertently resulted in data analyses on an inaccurate data set. When the error was discovered by the authors and corrected, all analyses reported in Experiment 6 for claim validity, seriousness of the claim, and support for the claimant were inaccurate and none were statistically significant. The conclusions should be altered to indicate that participants with management experience who reflected on their own workplace diversity policies did not show the predicted effects. The literature review, remaining five studies, and remaining conclusions in the article are unaffected by this error. Experiment 6 should also report that 26.4% (not 26.4.7%) of participants had a graduate degree and eight participants (not 8%) did not provide educational data. Experiment 5 should have referred to the claim validity measure as a six-item measure ( .92) rather than a five-item measure; analyses on claim validity are accurate in text. Table 2's note should have said standard errors, not standard deviations. (The following abstract of the original article appeared in record 2012-31077-001.) This research tests the hypothesis that the presence (vs. absence) of organizational diversity structures causes high-status group members (Whites, men) to perceive organizations with diversity structures as procedurally fairer environments for underrepresented groups (racial minorities, women), even when it is clear that underrepresented groups have been unfairly disadvantaged within these organizations. Furthermore, this illusory sense of fairness derived from the mere presence of diversity structures causes high

  14. Modulated Current Drive Measurements

    International Nuclear Information System (INIS)

    Petty, C.C.; Lohr, J.; Luce, T.C.; Prater, R.; Cox, W.A.; Forest, C.B.; Jayakumar, R.J.; Makowski, M.A.

    2005-01-01

    A new measurement approach is presented which directly determines the noninductive current profile from the periodic response of the motional Stark effect (MSE) signals to the slow modulation of the external current drive source. A Fourier transform of the poloidal magnetic flux diffusion equation is used to analyze the MSE data. An example of this measurement technique is shown using modulated electron cyclotron current drive (ECCD) discharges from the DIII-D tokamak

  15. Japan's Orientation towards Foreign Investments: Inertia Effects and Driving Force of Institutional Changes

    OpenAIRE

    Nir Kshetri; Ralf Bebenroth

    2012-01-01

    We use an institutional perspective to develop a framework for understanding the contexts, mechanisms and processes associated with institutions and institutional changes related to foreign investment in Japan. We examine power dynamics and relational boundaries between diverse actors and analyze why and how some components of institutions have changed and others have not. Also explored in this paper are the conflicting discourses that have been raised in regards to the participation of forei...

  16. Effects on driving performance of interacting with an in-vehicle music player: a comparison of three interface layout concepts for information presentation.

    Science.gov (United States)

    Mitsopoulos-Rubens, Eve; Trotter, Margaret J; Lenné, Michael G

    2011-05-01

    Interface design is an important factor in assessing the potential effects on safety of interacting with an in-vehicle information system while driving. In the current study, the layout of information on a visual display was manipulated to explore its effect on driving performance in the context of music selection. The comparative effects of an auditory-verbal (cognitive) task were also explored. The driving performance of 30 participants was assessed under both baseline and dual task conditions using the Lane Change Test. Concurrent completion of the music selection task with driving resulted in significant impairment to lateral driving performance (mean lane deviation and percentage of correct lane changes) relative to the baseline, and significantly greater mean lane deviation relative to the combined driving and the cognitive task condition. The magnitude of these effects on driving performance was independent of layout concept, although significant differences in subjective workload estimates and performance on the music selection task across layout concepts highlights that potential uncertainty regarding design use as conveyed through layout concept could be disadvantageous. The implications of these results for interface design and safety are discussed. Copyright © 2010 Elsevier Ltd and The Ergonomics Society. All rights reserved.

  17. Ecological Effects of Roads on the Plant Diversity of Coastal Wetland in the Yellow River Delta

    Directory of Open Access Journals (Sweden)

    Yunzhao Li

    2014-01-01

    Full Text Available The 26 sample sites in 7 study plots adjacent to asphalt road and earth road in coastal wetland in the Yellow River Delta were selected to quantify plant diversity using quadrat sampling method in plant bloom phase of July and August 2012. The indice of βT and Jaccard’s coefficient were applied to evaluate the species diversity. The results showed that the plant diversities and alien plants were high in the range of 0–20 m to the road verge. There were more exotics and halophytes in plots of asphalt roadside than that of earth roadside. However, proportion of halophytes in habitats of asphalt roadsides was lower than that of earth roadside. By comparing β-diversity, there were more common species in the asphalt roadsides than that in the earth roadsides. The similarity of plant communities in studied plots of asphalt roadsides and earth roadsides increased with increasing the distance to road verge. The effect range of roads for plant diversity in study region was about 20 m to road verge. Our results indicate that the construction and maintenance of roads in wetland could increase the plant species diversities of communities and risk of alien species invasion.

  18. Ecological Effects of Roads on the Plant Diversity of Coastal Wetland in the Yellow River Delta

    Science.gov (United States)

    Li, Yunzhao; Du, Siyao; Han, Guangxuan; Qu, Fanzhu; Wang, Guangmei; Fu, Yuqin; Zhan, Chao

    2014-01-01

    The 26 sample sites in 7 study plots adjacent to asphalt road and earth road in coastal wetland in the Yellow River Delta were selected to quantify plant diversity using quadrat sampling method in plant bloom phase of July and August 2012. The indice of β T and Jaccard's coefficient were applied to evaluate the species diversity. The results showed that the plant diversities and alien plants were high in the range of 0–20 m to the road verge. There were more exotics and halophytes in plots of asphalt roadside than that of earth roadside. However, proportion of halophytes in habitats of asphalt roadsides was lower than that of earth roadside. By comparing β-diversity, there were more common species in the asphalt roadsides than that in the earth roadsides. The similarity of plant communities in studied plots of asphalt roadsides and earth roadsides increased with increasing the distance to road verge. The effect range of roads for plant diversity in study region was about 20 m to road verge. Our results indicate that the construction and maintenance of roads in wetland could increase the plant species diversities of communities and risk of alien species invasion. PMID:25147872

  19. A simple method to prevent hard X-ray-induced preheating effects inside the cone tip in indirect-drive fast ignition implosions

    International Nuclear Information System (INIS)

    Liu, Dongxiao; Shan, Lianqiang; Zhou, Weimin; Wu, Yuchi; Zhu, Bin; Zhang, Feng; Bi, Bi; Zhang, Bo; Zhang, Zhimeng; Shui, Min; He, Yingling; Gu, Yuqiu; Zhang, Baohan; Peng, Xiaoshi; Xu, Tao; Wang, Feng; Yang, Zhiwen; Chen, Tao; Chen, Li; Chen, Ming

    2016-01-01

    During fast-ignition implosions, preheating of inside the cone tip caused by hard X-rays can strongly affect the generation and transport of hot electrons in the cone. Although indirect-drive implosions have a higher implosion symmetry, they cause stronger preheating effects than direct-drive implosions. To control the preheating of the cone tip, we propose the use of indirect-drive fast-ignition targets with thicker tips. Experiments carried out at the ShenGuang-III prototype laser facility confirmed that thicker tips are effective for controlling preheating. Moreover, these results were consistent with those of 1D radiation hydrodynamic simulations.

  20. A simple method to prevent hard X-ray-induced preheating effects inside the cone tip in indirect-drive fast ignition implosions

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Dongxiao; Shan, Lianqiang; Zhou, Weimin; Wu, Yuchi; Zhu, Bin; Zhang, Feng; Bi, Bi; Zhang, Bo; Zhang, Zhimeng; Shui, Min; He, Yingling; Gu, Yuqiu, E-mail: yqgu@caep.cn; Zhang, Baohan [Science and Technology on Plasma Physics Laboratory, China Academy of Engineering Physics, Mianyang 621900 (China); Research Center of Laser Fusion, China Academy of Engineering Physics, Mianyang 621900 (China); Peng, Xiaoshi; Xu, Tao; Wang, Feng; Yang, Zhiwen; Chen, Tao; Chen, Li; Chen, Ming [Research Center of Laser Fusion, China Academy of Engineering Physics, Mianyang 621900 (China); and others

    2016-06-15

    During fast-ignition implosions, preheating of inside the cone tip caused by hard X-rays can strongly affect the generation and transport of hot electrons in the cone. Although indirect-drive implosions have a higher implosion symmetry, they cause stronger preheating effects than direct-drive implosions. To control the preheating of the cone tip, we propose the use of indirect-drive fast-ignition targets with thicker tips. Experiments carried out at the ShenGuang-III prototype laser facility confirmed that thicker tips are effective for controlling preheating. Moreover, these results were consistent with those of 1D radiation hydrodynamic simulations.

  1. Clarifying the Effects of Human Resource Diversity Management Practices on Organizational Citizenship Behavior: The Mediating Role of Diversity Receptiveness

    Directory of Open Access Journals (Sweden)

    Ahmad Nizan Mat Noor

    2014-06-01

    Full Text Available The aim of this study is to scrutinize the impact of employees’ perceptions of their organization’s human resource diversity management (HRDM practices on their organizational citizenship behavior (OCB level. The influence of diversity receptiveness as a mediator in the proposed relationship is also examined. Survey data were gathered from operational employees attached to large hotel in Malaysia. 430 usable questionnaires were used in statistical analyses. The results indicated that the hypothesized linkage between HRDM practices and diversity receptiveness as well as between HRDM practices and OCB were partially supported. The mediating role of diversity receptiveness in the relationship was also partially supported. Implications and limitations of the findings are specified. Finally, directions for future research are suggested.

  2. Effects of Tunnel Design Characteristics on Driving Behaviour and Traffic Safety: A Literature Review (Effecten van tunnelontwerpkenmerken op rijgedrag en verkeersveiligheid: Een literatuurstudie)

    National Research Council Canada - National Science Library

    Martens, M

    1997-01-01

    .... This may affect the level of driving safety. This literature review provides an overview of the effect of tunnel design characteristics on road user behaviour, and can serve as a basis for recommendations on specific tunnel design standards...

  3. Effect of resonant-to-bulk electron momentum transfer on the efficiency of electron-cyclotron current drive

    International Nuclear Information System (INIS)

    Matsuda, Y.; Smith, G.R.; Cohen, R.H.

    1988-01-01

    Efficiency of current drive by electron-cyclotron waves is investigated numerically by a bounce-average Fokker-Planck code to elucidate the effects of momentum transfer from resonant to bulk electrons, finite bulk temperature relative to the energy of resonant electrons, and trapped electrons. Comparisons are made with existing theories to assess their validity and quantitative difference between theory and code results. Difference of nearly a factor of 2 was found in efficiency between some theory and code results. 4 refs., 4 figs

  4. Neoclassical tearing modes in DIII-D and calculations of the stabilizing effects of localized electron cyclotron current drive

    International Nuclear Information System (INIS)

    Prater, R.; La Haye, R. J.; Lin-Liu, Y. R.; Lohr, J.; Perkins, F. W.; Bernabei, S.; Wong, K.-L.; Harvey, R. W.

    1999-01-01

    Neoclassical tearing modes are found to limit the achievable beta in many high performance discharges in DIII-D. Electron cyclotron current drive within the magnetic islands formed as the tearing mode grows has been proposed as a means of stabilizing these modes or reducing their amplitude, thereby increasing the beta limit by a factor around 1.5. Some experimental success has been obtained previously on Asdex-U. Here we examine the parameter range in DIII-D in which this effect can best be studied

  5. Resonant Activation in a Stochastic Hodgkin-Huxley Model: Interplay between noise and suprathreshold driving effect

    DEFF Research Database (Denmark)

    Pankratova, Evgeniya; Polovinkin, A.V.; Mosekilde, Erik

    2005-01-01

    The paper considers an excitable Hodgkin-Huxley system subjected to a strong periodic forcing in the presence of random noise. The influence of the forcing frequency on the response of the system is examined in the realm of suprathreshold amplitudes. Our results confirm that the presence of noise...... a minimum as functions of the forcing frequency. The destructive influence of noise on the interspike interval can also be reduced. With driving signals in a certain frequency range, the system can show stable periodic spiking even for relatively large noise intensities. Outside this frequency range, noise...... of similar intensity destroys the regularity of the spike trains by suppressing the generation of some of the spikes....

  6. A field study on the effects of digital billboards on glance behavior during highway driving.

    Science.gov (United States)

    Belyusar, Daniel; Reimer, Bryan; Mehler, Bruce; Coughlin, Joseph F

    2016-03-01

    Developments in lighting technologies have allowed more dynamic digital billboards in locations visible from the roadway. Decades of laboratory research have shown that rapidly changing or moving stimuli presented in peripheral vision tends to 'capture' covert attention. We report naturalistic glance and driving behavior of a large sample of drivers who were exposed to two digital billboards on a segment of highway largely free from extraneous signage. Results show a significant shift in the number and length of glances toward the billboards and an increased percentage of time glancing off road in their presence. Findings were particularly evident at the time the billboards transitioned between advertisements. Since rapidly changing stimuli are difficult to ignore, the planned increase in episodically changing digital displays near the roadway may be argued to be a potential safety concern. The impact of digital billboards on driver safety and the need for continued research are discussed. Copyright © 2015 Elsevier Ltd. All rights reserved.

  7. [Sleep deprivation and its effect on the ability to maintain wakefulness: implications on functioning and driving].

    Science.gov (United States)

    Furman, Gabriela Dorfman; Cahan, Clement; Baharav, Armada

    2009-05-01

    During the last century, western society suffers from an increasing steep debt. A large number of accidents occur due to drowsy drivers. People are not aware of the influence of fatigue/drowsiness on their functioning and driving capacity. Our goal is to identify and characterize measurable physioLogicaL information capable of monitoring simple and reliable performance of driver vigilance. Eight healthy volunteers without sleep disorders were included in the study. They participated in two missions, on and off every two hours during 34-36 hours, in order to create an accumulative sleep debt. The tasks included the Maintenance of wakefulness test (MWT) and the driving simulator test. White tested, they remained connected to EEG, EMG, EOG, ECG and audio-video registration. These first results are related to 60 MWT tests. The first falling asleep events (FA) appeared around the early afternoon hours, in agreement to the physiological tendency to fall asleep, according to the biological clock. The night was characterized by FAs with a very short sleep Latency time at around 4 AM. On the second day of the experiment, the averaged sleep latency was larger than in the night before, despite the accumulation of sleep debt. The fluctuations of RRI increased after the first micro sleep. The autonomic nervous regulation displays an increase in the overall sympathetic activity as an indicator of increased stress. There is a correlation between parameters associated with instantaneous autonomic changes of heart rhythm (RRI) and the FA/almost-FA events observed on EEG. These attributes may provide a useful tool for monitoring drowsy drivers and preventing accidents.

  8. The effects of driving cessation on the elderly with dementia and their caregivers.

    Science.gov (United States)

    Taylor, B D; Tripodes, S

    2001-07-01

    This research explores how the loss of driving privileges by impaired drivers affects households. The particular focus is on the travel behavior and preceptions of people living in households where an elderly driver has had his or her license revoked due to Alzheimer's disease or a related dementia. The data for this analysis were drawn from a 1996 survey of households in California which queried the caregivers of people with dementia on how the former drivers access necessary destinations once they can no longer drive, and on the difficulties faced by other household members in seeking alternative means of transportation. After losing their license, the vast majority of people surveyed depended on informal support systems for transportation, such as rides from family and friends. Although such arrangements were not reported to be a problem for the majority of households, certain groups of non-drivers reported difficulty accessing services, particularly social and recreational destinations. The most commonly reported problem was a lack of available licensed drivers to chauffeur non-drivers. Importantly, no increase was observed in the number of people walking, using public transit, taxis, or van services following license revocation. People who did not live with at least one licensed driver and those who were younger and healthier reported the greatest mismatch between their need and desire to travel and the availability of transportation. In addition, some caregivers reported that they frequently missed work or stopped working entirely in order to care for and chauffeur people in the former drivers' household. Overall, these findings reinforce the importance of both developing transportation policies to support the functioning of informal transportation structures and in improving the range of alternative transportation options for those individuals with particular disabilities--like dementia--who are not well served by either informal arrangements or by formal

  9. The Effects of Crop Intensification on the Diversity of Native Pollinator Communities.

    Science.gov (United States)

    Mogren, Christina L; Rand, Tatyana A; Fausti, Scott W; Lundgren, Jonathan G

    2016-08-01

    Increases in agricultural conversion are leading to declines in native grasslands and natural resources critical for beneficial insects. However, little is known regarding how these changes affect pollinator diversity. Land use types were categorized within 300 m and 3 km radii of pollinator sampling locations in Brookings County, SD. Pollinator abundance and species richness were regressed on the proportion of the landscape dedicated to row crops, grass and pasture, forage crops, small grains, and aquatic habitats using variance components modeling. Row crops had a negative effect on bee abundance at 300 m, after fixed effects modeling accounted for outliers skewing this relationship. At 3 km, corn positively affected bee abundance and richness, while soybean acreage decreased species richness. The landscape matrix of outlying sites consisted of large monocultured areas with few alternative habitat types available, leading to inflated populations of Melissodes and Halictidae. Syrphids had a positive parabolic relationship between diversity and row crops, indicating potential for competitive exclusion from intermediate landscapes. Unlike other studies, landscape diversity within 300 m was not found to significantly benefit pollinator diversity. Within especially agriculturally developed areas of the region, high abundances of pollinators suggest selection for a few dominant species. There was no effect of forage crops or aquatic habitats on pollinator diversity, indicating that less highly managed areas still represent degraded habitat within the landscape. Incorporating pollinator-friendly crops at the farm level throughout the region is likely to enhance pollinator diversity by lessening the negative effects of large monocultures. © The Authors 2016. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  10. Change detection in urban and rural driving scenes: Effects of target type and safety relevance on change blindness.

    Science.gov (United States)

    Beanland, Vanessa; Filtness, Ashleigh J; Jeans, Rhiannon

    2017-03-01

    The ability to detect changes is crucial for safe driving. Previous research has demonstrated that drivers often experience change blindness, which refers to failed or delayed change detection. The current study explored how susceptibility to change blindness varies as a function of the driving environment, type of object changed, and safety relevance of the change. Twenty-six fully-licenced drivers completed a driving-related change detection task. Changes occurred to seven target objects (road signs, cars, motorcycles, traffic lights, pedestrians, animals, or roadside trees) across two environments (urban or rural). The contextual safety relevance of the change was systematically manipulated within each object category, ranging from high safety relevance (i.e., requiring a response by the driver) to low safety relevance (i.e., requiring no response). When viewing rural scenes, compared with urban scenes, participants were significantly faster and more accurate at detecting changes, and were less susceptible to "looked-but-failed-to-see" errors. Interestingly, safety relevance of the change differentially affected performance in urban and rural environments. In urban scenes, participants were more efficient at detecting changes with higher safety relevance, whereas in rural scenes the effect of safety relevance has marginal to no effect on change detection. Finally, even after accounting for safety relevance, change blindness varied significantly between target types. Overall the results suggest that drivers are less susceptible to change blindness for objects that are likely to change or move (e.g., traffic lights vs. road signs), and for moving objects that pose greater danger (e.g., wild animals vs. pedestrians). Copyright © 2017 Elsevier Ltd. All rights reserved.

  11. The diversity effect of inductive reasoning under segment manipulation of complex cognition.

    Science.gov (United States)

    Chen, Antao; Li, Hong; Feng, Tingyong; Gao, Xuemei; Zhang, Zhongming; Li, Fuhong; Yang, Dong

    2005-12-01

    The present study proposed the idea of segment manipulation of complex cognition (SMCC), and technically made it possible the quantitative treatment and systematical manipulation on the premise diversity. The segment manipulation of complex cognition divides the previous inductive strengths judgment task into three distinct steps, attempting to particularly distinguish the psychological processes and their rules. The results in Experiment 1 showed that compared with the traditional method, the quantitative treatment and systematical manipulation of SMCC on the diversity did not change the task's nature, and remain rational and a good measurement of inductive strength judgment. The results in Experiment 2 showed that the participants' response rules in the triple-step task were expected from our proposal, and that in Step 2 the "feeling of surprise" (FOS), which seems implausible but predicted from the diversity premises, was measured, and its component might be the critical part that produced the diversity effect. The "feeling of surprise" may reflect the impact of emotion on cognition, representing a strong revision to premise probability principle of pure rational hypothesis proposed by Lo et al., and its roles in the diversity effect are worthy of further research. In this regards were discussed the mistakes that the premise probability principle makes when it takes posterity probability as prior probability.

  12. Cultural Transmission on the Taskscape: Exploring the Effects of Taskscape Visibility on Cultural Diversity.

    Science.gov (United States)

    Premo, L S; Tostevin, Gilbert B

    2016-01-01

    Culturally transmitted behavior can be structured in its performance both geographically and temporally, in terms of where and when implements are made and used on the landscape (what Ingold calls "the taskscape"). Yet cultural transmission theory has not yet explored the consequences of behaviors transmitted differently due to their enactment at different taskscape locations, what Tostevin calls "taskscape visibility." Here, we use computer simulations to explore how taskscape visibility and forager mobility affect the diversity of two selectively neutral culturally transmitted traits within a single population of social learners. The trait that can be transmitted from residential bases only (lower taskscape visibility) shows greater diversity than the trait that can be transmitted from residential bases and logistical camps (higher taskscape visibility). In addition, increased logistical mobility has a positive effect on the diversity of the trait with the lower taskscape visibility while it generally shows little to no effect on the diversity of the trait with higher taskscape visibility. Without an appreciation for the ways in which taskscape visibility and mobility can structure cultural transmission in space and through time, the difference in the observed equilibrium diversity levels of the two traits might be incorrectly interpreted as resulting from qualitatively different forms of biased cultural transmission. The results of our simulation experiment suggest that researchers may need to take the taskscape visibility into account when inferring cultural transmission from archaeological data.

  13. Effectiveness of enforcement levels of speed limit and drink driving laws and associated factors – Exploratory empirical analysis using a bivariate ordered probit model

    Directory of Open Access Journals (Sweden)

    Behram Wali

    2017-06-01

    Full Text Available The contemporary traffic safety research comprises little information on quantifying the simultaneous association between drink driving and speeding among fatally injured drivers. Potential correlation between driver's drink driving and speeding behavior poses a substantial methodological concern which needs investigation. This study therefore focused on investigating the simultaneous impact of socioeconomic factors, fatalities, vehicle ownership, health services and highway agency road safety policies on enforcement levels of speed limit and drink driving laws. The effectiveness of enforcement levels of speed limit and drink driving laws has been investigated through development of bivariate ordered probit model using data extricated from WHO's global status report on road safety in 2013. The consistent and intuitive parameter estimates along with statistically significant correlation between response outcomes validates the statistical supremacy of bivariate ordered probit model. The results revealed that fatalities per thousand registered vehicles, hospital beds per hundred thousand population and road safety policies are associated with a likely medium or high effectiveness of enforcement levels of speed limit and drink driving laws, respectively. Also, the model encapsulates the effect of several other agency related variables and socio-economic status on the response outcomes. Marginal effects are reported for analyzing the impact of such factors on intermediate categories of response outcomes. The results of this study are expected to provide necessary insights to elemental enforcement programs. Also, marginal effects of explanatory variables may provide useful directions for formulating effective policy countermeasures for overcoming driver's speeding and drink driving behavior.

  14. Community Drive

    DEFF Research Database (Denmark)

    Magnussen, Rikke

    2018-01-01

    Schools and educational institutions are challenged by not adequately educating students for independent knowledge collaboration and solving of complex societal challenges (Bundsgaard & Hansen, 2016; Slot et al., 2017). As an alternative strategy to formal learning has Community-driven research...... opportunity to break boundaries between research institutions and surrounding communities through the involvement of new types of actors, knowledge forms and institutions (OECD, 2011). This paper presents the project Community Drive a three year cross disciplinary community-driven game– and data-based project....... In the paper we present how the project Community Drive initiated in May 2018 is based on results from pilot projects conducted from 2014 – 2017. Overall these studies showed that it is a strong motivational factor for students to be given the task to change their living conditions through redesign...

  15. Driver headway choice : A comparison between driving simulator and real-road driving

    NARCIS (Netherlands)

    Risto, M.; Martens, M.H.

    2014-01-01

    Driving simulators have become an established tool in driver behaviour research by offering a controllable, safe and cost-effective alternative to real world driving. A challenge for using driving simulators as a research tool has been to elicit driving behaviour that equals real world driving. With

  16. Driver headway choice: a comparison between driving simulator and real-road driving

    NARCIS (Netherlands)

    Risto, Malte; Martens, Marieke Hendrikje

    2014-01-01

    Driving simulators have become an established tool in driver behaviour research by offering a controllable, safe and cost-effective alternative to real world driving. A challenge for using driving simulators as a research tool has been to elicit driving behaviour that equals real world driving. With

  17. Effects of Different Types of Cognitive Training on Cognitive Function, Brain Structure, and Driving Safety in Senior Daily Drivers: A Pilot Study

    Science.gov (United States)

    Taki, Yasuyuki; Kanno, Akitake; Akimoto, Yoritaka; Ihara, Mizuki; Yokoyama, Ryoichi; Kotozaki, Yuka; Sekiguchi, Atsushi; Takeuchi, Hikaru; Miyauchi, Carlos Makoto; Ogawa, Takeshi; Goto, Takakuni; Sunda, Takashi; Shimizu, Toshiyuki; Tozuka, Eiji; Hirose, Satoru; Nanbu, Tatsuyoshi; Kawashima, Ryuta

    2015-01-01

    Background. Increasing proportion of the elderly in the driving population raises the importance of assuring their safety. We explored the effects of three different types of cognitive training on the cognitive function, brain structure, and driving safety of the elderly. Methods. Thirty-seven healthy elderly daily drivers were randomly assigned to one of three training groups: Group V trained in a vehicle with a newly developed onboard cognitive training program, Group P trained with a similar program but on a personal computer, and Group C trained to solve a crossword puzzle. Before and after the 8-week training period, they underwent neuropsychological tests, structural brain magnetic resonance imaging, and driving safety tests. Results. For cognitive function, only Group V showed significant improvements in processing speed and working memory. For driving safety, Group V showed significant improvements both in the driving aptitude test and in the on-road evaluations. Group P showed no significant improvements in either test, and Group C showed significant improvements in the driving aptitude but not in the on-road evaluations. Conclusion. The results support the effectiveness of the onboard training program in enhancing the elderly's abilities to drive safely and the potential advantages of a multimodal training approach. PMID:26161000

  18. Effects of Different Types of Cognitive Training on Cognitive Function, Brain Structure, and Driving Safety in Senior Daily Drivers: A Pilot Study

    Directory of Open Access Journals (Sweden)

    Takayuki Nozawa

    2015-01-01

    Full Text Available Background. Increasing proportion of the elderly in the driving population raises the importance of assuring their safety. We explored the effects of three different types of cognitive training on the cognitive function, brain structure, and driving safety of the elderly. Methods. Thirty-seven healthy elderly daily drivers were randomly assigned to one of three training groups: Group V trained in a vehicle with a newly developed onboard cognitive training program, Group P trained with a similar program but on a personal computer, and Group C trained to solve a crossword puzzle. Before and after the 8-week training period, they underwent neuropsychological tests, structural brain magnetic resonance imaging, and driving safety tests. Results. For cognitive function, only Group V showed significant improvements in processing speed and working memory. For driving safety, Group V showed significant improvements both in the driving aptitude test and in the on-road evaluations. Group P showed no significant improvements in either test, and Group C showed significant improvements in the driving aptitude but not in the on-road evaluations. Conclusion. The results support the effectiveness of the onboard training program in enhancing the elderly’s abilities to drive safely and the potential advantages of a multimodal training approach.

  19. Effects of Different Types of Cognitive Training on Cognitive Function, Brain Structure, and Driving Safety in Senior Daily Drivers: A Pilot Study.

    Science.gov (United States)

    Nozawa, Takayuki; Taki, Yasuyuki; Kanno, Akitake; Akimoto, Yoritaka; Ihara, Mizuki; Yokoyama, Ryoichi; Kotozaki, Yuka; Nouchi, Rui; Sekiguchi, Atsushi; Takeuchi, Hikaru; Miyauchi, Carlos Makoto; Ogawa, Takeshi; Goto, Takakuni; Sunda, Takashi; Shimizu, Toshiyuki; Tozuka, Eiji; Hirose, Satoru; Nanbu, Tatsuyoshi; Kawashima, Ryuta

    2015-01-01

    Increasing proportion of the elderly in the driving population raises the importance of assuring their safety. We explored the effects of three different types of cognitive training on the cognitive function, brain structure, and driving safety of the elderly. Thirty-seven healthy elderly daily drivers were randomly assigned to one of three training groups: Group V trained in a vehicle with a newly developed onboard cognitive training program, Group P trained with a similar program but on a personal computer, and Group C trained to solve a crossword puzzle. Before and after the 8-week training period, they underwent neuropsychological tests, structural brain magnetic resonance imaging, and driving safety tests. For cognitive function, only Group V showed significant improvements in processing speed and working memory. For driving safety, Group V showed significant improvements both in the driving aptitude test and in the on-road evaluations. Group P showed no significant improvements in either test, and Group C showed significant improvements in the driving aptitude but not in the on-road evaluations. The results support the effectiveness of the onboard training program in enhancing the elderly's abilities to drive safely and the potential advantages of a multimodal training approach.

  20. The Effects of Diversity Management on Job Satisfaction and Individual Performance of Teachers

    Science.gov (United States)

    Ordu, Aydan

    2016-01-01

    In this research, the effects of teachers' perceptions of the diversity management on their job satisfaction and individual performance were examined. Teachers who are working in public high schools during 2014 to 2015 academic year constituted the study group of the research. The data of the research in which quantitative method used were…

  1. Effects of Deforestation on Natural Bio-Diversity in Delta North ...

    African Journals Online (AJOL)

    The study examines the effects of deforestation on natural bio-diversity in Delta North Region of Delta State, with the aim of determining the extent of tree species loss. Vegetation physiognomy of tree height, tree diameter and tree species population were measured in forested and deforested areas. Two experimental sites ...

  2. Effects of Diversity Experiences on Socially Responsible Leadership over Four Years of College

    Science.gov (United States)

    Parker, Eugene T., III; Pascarella, Ernest T.

    2013-01-01

    Regarding collegiate experiences, several studies have examined the effects of diversity experiences on educational, psychosocial, and other college outcomes (Pascarella & Terenzini, 2005). However, there exists a limited body of research, which has focused on the impact of those types of experiences on leadership development among students…

  3. Recovery of the incretin effect in type 2 diabetic patients after biliopancreatic diversion

    DEFF Research Database (Denmark)

    Novaes, Fernanda S; Vasques, Ana C J; Pareja, José C

    2015-01-01

    CONTEXT: Bariatric surgery often results in remission of the diabetic state in obese patients. Increased incretin effect seems to play an important role in the glycemic improvements after Roux-en-Y gastric bypass, but the impact of biliopancreatic diversion (BPD) remains unexplored. OBJECTIVE: Th...

  4. Intercultural Leadership Toolkit for Librarians: Building Awareness to Effectively Serve Diverse Multicultural Populations

    Science.gov (United States)

    Allard, Suzie; Mehra, Bharat; Qayyum, M. Asim

    2007-01-01

    This paper presents five tools for librarians to use in building effective intercultural communication that reaches out to diverse populations. Librarians can more successfully cross intercultural boundaries if they are aware of the key tenets of intercultural communication and information provision, and then apply the five leadership tools in…

  5. The Effect of Art Therapy on Cognitive Performance among Ethnically Diverse Older Adults

    Science.gov (United States)

    Pike, Amanda Alders

    2013-01-01

    This study examined the effect of art therapy on the cognitive performance of a multisite, ethnically diverse sample ("N" = 91) of older adults. Participants were recruited from several U.S. facilities that included a community center, a retirement center, an adult daycare, an assisted living facility, and a skilled nursing facility.…

  6. Leadership and organizational tenure diversity as determinants of project team effectiveness

    NARCIS (Netherlands)

    de Poel, Frouke M.; Stoker, Janka I.; Van der Zee, Karen I.

    2014-01-01

    The present study reveals how leadership effectiveness in project teams is dependent on the level of organizational tenure diversity. Data from 34 project teams showed that transformational leadership is related to organizational commitment, creative behavior, and job satisfaction, but only in teams

  7. Effects of plant species identity, diversity and soil fertility on biodegradation of phenanthrene in soil

    NARCIS (Netherlands)

    Oyelami, A.O.; Okere, U.V.; Orwin, K.; Deyn, de G.B.; Jones, K.C.; Semple, K.T.

    2013-01-01

    The work presented in this paper investigated the effects of plant species composition, species diversity and soil fertility on biodegradation of 14C-phenanthrene in soil. The two soils used were of contrasting fertility, taken from long term unfertilised and fertilised grassland, showing

  8. Minority Adolescents in Ethnically Diverse Schools: Perceptions of Equal Treatment Buffer Threat Effects

    Science.gov (United States)

    Baysu, Gülseli; Celeste, Laura; Brown, Rupert; Verschueren, Karine; Phalet, Karen

    2016-01-01

    Can perceptions of equal treatment buffer the negative effects of threat on the school success of minority students? Focusing on minority adolescents from Turkish and Moroccan heritage in Belgium (M[subscript age] = 14.5; N = 735 in 47 ethnically diverse schools), multilevel mediated moderation analyses showed: (a) perceived discrimination at…

  9. Leadership and Organizational Tenure Diversity as Determinants of Project Team Effectiveness

    NARCIS (Netherlands)

    de Poel, Frouke M.; Stoker, Janka I.; Van der Zee, Karen I.

    2014-01-01

    The present study reveals how leadership effectiveness in project teams is dependent on the level of organizational tenure diversity. Data from 34 project teams showed that transformational leadership is related to organizational commitment, creative behavior, and job satisfaction, but only in teams

  10. The Effect of Diversity Climate Perception on Alienation of Students to University

    Science.gov (United States)

    Kurtulmus, Mehmet

    2016-01-01

    The aim of this research is to examine the effect of diversity climate perception on alienation of students to university. The research was carried out with relational survey model. 333 undergraduate students in Faculty of Education, Medical, and Faculty of Theology of Dicle University constituted the participant group. Research data were…

  11. Diversity effects on root length production and loss in an experimental grassland community

    NARCIS (Netherlands)

    Mommer, L.; Padilla, F.M.; Ruijven, van J.; Caluwe, de H.; Smit-Tiekstra, A.E.; Berendse, F.; Kroon, de H.

    2015-01-01

    Advances in root ecology have revealed that root standing biomass is higher in species-rich plant communities than in species-poor communities. Currently, we do not know whether this below-ground diversity effect is the result of enhanced root production or reduced root mortality or both, which is

  12. The effects of diversity faultlines and team task autonomy on decision quality and social integration

    NARCIS (Netherlands)

    Rico, Ramon; Molleman, Eric; Sanchez-Manzanares, Miriam; Van der Vegt, Gerben S.

    This study examines the effects of diversity faultlines stemming from educational background and conscientiousness on team decision quality and social integration and the moderating role of team task autonomy. Using a 2 x 2 (Weak/Strong Faultlines x Low/High Team Task Autonomy) factorial design, 52

  13. Effect of some socio-economic activities on fish diversity of lagoon ...

    African Journals Online (AJOL)

    Effect of some socio-economic activities on fish diversity of lagoon systems in Ogun waterside Local Government of Ogun State, Nigeria. ... The PDF file you selected should load here if your Web browser has a PDF reader plug-in installed (for example, a recent version of Adobe Acrobat Reader). If you would like more ...

  14. Modulation of the effects of alcohol on driving-related psychomotor skills by chronic exposure to cannabis.

    Science.gov (United States)

    Wright, A; Terry, P

    2002-03-01

    Many previous studies have reported that alcohol and cannabis produce additive psychomotor effects in acute combination, but few have explicitly tested whether chronic exposure to cannabis, in the absence of acute administration, alters the effects of alcohol on psychomotor performance. To test whether long-term cannabis use modulates the effects of alcohol on psychomotor skills and self-reported mood and sensation. Regular cannabis users (minimum: daily use for at least 3 years) and infrequent users (maximum: once-monthly use for at most 3 years) were matched for sex, age, alcohol intake and other drug use (14 participants in each group). Participants received alcohol (females 0.35 g/kg; males 0.45 g/kg) and placebo drinks. By urinalysis, only regular users tested positive for metabolites of Delta(9)-tetrahydrocannabinol; breath alcohol levels were similar between groups. Participants were tested on a computerised tracking task that has been used to screen drugs for adverse effects on driving. The task involved tracking a moving target on a computer screen while simultaneously responding to occasional presentations of stimuli in the periphery of the screen. Tracking accuracy was similar for both groups after placebo, but alcohol caused a significant deterioration in performance among infrequent cannabis users relative to regular users. These changes were mirrored by significant changes in self-reported scores for dizziness, measured by visual analogue scales. Alcohol slowed reaction times, but not differentially between groups. For psychomotor skills relevant to driving, chronic cannabis use (in the absence of acute administration) does not potentiate the effects of alcohol. In fact, the superior tracking accuracy of regular users relative to infrequent users after alcohol, and their lower scores for dizziness, suggest that chronic cannabis use may instead confer cross-tolerance to specific effects of alcohol on behaviour.

  15. The Effects of External Focus of Attention on Shoulder Muscle Activities during Forehand Drive in Table Tennis

    Directory of Open Access Journals (Sweden)

    Mohammad Reza Hatami

    2016-06-01

    Full Text Available Objective: The aim of this study was to evaluate the impact of the external focus of attention on the rotator cuff muscle activity for the timely hit forehand drive by table tennis players. Methods: Twelve professional table tennis players with mean age of 26.5 years voluntarily participated in this study. The electrical activities of the muscles of the shoulder girdle using M.A 300 machine and bipolar electrodes surface under two conditions .First with external focus of attention and then without such attention were recorded, first without any guidance blows forehand drive was carried out by subjects (without focus. Then such subject was asked to focus their attention on the area marked for the ball landing (external focus of attention.      Muscle activities in both preparation and tapping phases were analyzed the three –dimensional (200 Hz, Vicon, with four camera series T motion analysis system was used to obtain the data. Data was analyzed by running reported measures ANOVA at a significance level of p0.05 but the different between the intensity of muscle activity was meaningful. This suggests that there is a mutual influence between the two attention factors and muscles (p=0.03, that is, orientation can have a significant effect on the severity of muscle contraction. Intensities of muscle contraction in the preparation and tapping were different (p<0.05. Conclusion: On the forehand drive technique, the anterior deltoid muscle has the most activity. The type of focus and attention had a significant impact on the change of activity of muscles relative to each other, and the greatest impact is on the reduction of activity of the infraspinatus muscle. This type of focus delays fatigue and results in an increase in the efficiency of neuromuscular in the activities of skills.

  16. Driving mechanism of SOL plasma flow and effects on the divertor performance in JT-60U

    International Nuclear Information System (INIS)

    Asakura, N.; Takenaga, H.; Sakurai, S.

    2003-01-01

    The measurements of the SOL flow and plasma profiles both at the high-field-side (HFS) and low field- side (LFS), for the first time, identified the SOL flow pattern and its driving mechanism. 'Flow reversal' was found near the HFS and LFS separatrix of the main plasma for the ion ∇β drift direction towards the divertor. Radial profiles of the SOL flow were similar to those calculated numerically using the UEDGE code with the plasma drifts included although Mach numbers in measurements were greater than those obtained numerically. Particle fluxes towards the HFS and LFS divertors produced by the parallel SOL flow and E r xB drift flow were evaluated. The particle flux for the case of intense gas puff and divertor pump (puff and pump) was investigated, and it was found that both the Mach number and collisionality were enhanced, in particular, at HFS. Drift flux in the private flux region was also evaluated, and important physics issues for the divertor design and operation, such as in-out asymmetries of the heat and particle fluxes, and control of impurity ions were investigated. (author)

  17. Driving mechanism of SOL plasma flow and effects on the divertor performance in JT-60U

    International Nuclear Information System (INIS)

    Asakura, N.

    2002-01-01

    SOL plasma flow plays an important role in the plasma transport along the field lines, and influences control of the divertor plasma and impurity ions. Recently, mechanisms producing the SOL flow such as drifts produced by electric field and pressure gradient are pointed out. In JT-60U, three reciprocating Mach probes were installed at the high-field-side (HFS) baffle, low-field-side (LFS) midplane and just below the X-point. The measurements of the SOL flow and plasma profiles both at the HFS and LFS, for the first time, found out the SOL flow pattern and its driving mechanism. 'Flow reversal' was found near the separatrix of the HFS and LFS. Radial profiles of the SOL flow were similar to those calculated numerically using the UEDGE code with the plasma drifts included. SOL particle fluxes towards the HFS and LFS divertors were, for the first time, evaluated. Important physics issues for the divertor design and operation, such as in-out asymmetries of the heat and particle fluxes, and control of impurity ions with intense gas puff and divertor pump (puff and pump), were investigated. (author)

  18. Driving mechanism of SOL plasma flow an effects on the divertor performance in JT-60U

    International Nuclear Information System (INIS)

    Asakura, Nobuyuki; Takenaga, H.; Sakurai, S.

    2003-01-01

    The measurements of the scrape-off layer(SOL) flow and plasma profiles both at the high-field-side (HFS) and low-field-side (LFS), for the first time, identified the SOL flow pattern and its driving mechanism. 'Flow reversal' was found near the HFS and LFS separatrix of the main plasma for the ion ∇B drift direction towards the divertor, Radial profiles of the SOL flow were similar to those calculated numerically using the UEDGE code with the plasma drifts included although Mach numbers in measurements were greater than those obtained numerically. Particle fluxes towards the HFS and LFS divertors produced by the parallel SOL flow and E r xB drift flow were evaluated. The particle flux for the case of intense gas puff and divertor pump (puff and pump) was investigated, and it was found that both the Mach number and collisionality were enhanced, in particular, at HFS. Drift flux in the private flux region was also evaluated, and important physics issues for the divertor design and operation, such as in-out asymmetries of the heat and particle fluxes, and control of impurity ions were investigated. (author)

  19. Collective effects and experimental verification of the CLIC drive beam and decelerator

    CERN Document Server

    AUTHOR|(INSPIRE)INSPIRE-00418229; Stapnes, Steinar; Adli, Erik

    The Compact Linear Collider (CLIC) is a potential next-generation particle collider, in which electrons and positrons collide at a center-of-mass energy of up to 3 TeV. In order to reach a high accelerating gradient and reduce the length of the machine, CLIC uses a novel two-beam scheme. Here, the acceleration energy for the main beam is provided by energy extraction from a secondary electron drive beam, by the use of Power Extraction and Transfer Structures (PETS). This Ph.D. thesis describes deceleration measurements from the CLIC Test Facility 3 at CERN, from a beam that had up to 37 % of its kinetic energy converted into 12 GHz rf power. The results are part of the feasibility demonstration of the CLIC scheme. The measured difference in beam energy of the decelerated beam is correlated with particle tracking simulations and with predictions based on analytical formulae, and a very good agreement is demonstrated. The evolution of the transverse emittance was also studied, since it is critical to contain th...

  20. Two-dimensional and relativistic effects in lower-hybrid current drive

    International Nuclear Information System (INIS)

    Hewett, D.; Hizanidis, K.; Krapchev, V.; Bers, A.

    1983-06-01

    We present new numerical and analytic solutions of the two-dimensional Fokker-Planck equation supplemented by a parallel quasilinear diffusion term. The results show a large enhancement of the perpendicular temperature of both the electrons resonant with the applied RF fields and the more energetic electrons in the tail. Both the RF-generated current and power dissipated are substantially increased by the perpendicular energy broadening in the resonant region. In the presence of a small DC electric field the RF current generated is very much enhanced, much more than in a simple additive fashion. In addition, we present a relativistic formulation of the two-dimensional Fokker-Planck quasilinear equation. From conservation equations, based upon this formulation, we derive the characteristics of RF current drive with energetic electrons. These show how the RF-driven current and its figure of merit (I/P/sub d/) increase with the energy of the current-carrying electrons, and that their perpendicular, random momentum must also increase

  1. Competition as an Effective Tool in Developing Social Marketing Programs: Driving Behavior Change through Online Activities

    Directory of Open Access Journals (Sweden)

    Corina ŞERBAN

    2011-12-01

    Full Text Available Nowadays, social marketing practices represent an important part of people’s lives. Consumers’ understanding of the need for change has become the top priority for social organizations worldwide. As a result, the number of social marketing programs has increased, making people reflect more on their behaviors and on the need to take action. Competition in social marketing can bring many benefits. The more programs initiated, the more people will start to involve in society’s problems, hereby contributing to beneficial causes. However, social organizations are in the search for competitive advantages to differentiate them on the market. This paper aims to present the role of online communication in driving competitive advantage for social organizations. Using the structural equation model, the paper describes the relations between four characteristics of the online communication: credibility, attractiveness, persuasion and promotion and then presents the correlations between these variables and website competitiveness. The resulting model shows that owning a competitive advantage in social marketing can bring many advantages to both the non-profit organization and the consumer. Therefore, the online environment can be considered a good solution for better serving consumers’ social needs. Its contribution is significant especially in programs for children and adolescents, since teenagers spend more time on the Internet than adults and are more open to using the online channels of communication. In conclusion, this article opens new opportunities for social marketers to address society’s problems and supports the integration of the online communication tools in the competition strategy.

  2. Inverter Output Filter Effect on PWM Motor Drives of a Flywheel Energy Storage System

    Science.gov (United States)

    Santiago, Walter

    2004-01-01

    NASA Glenn Research Center (GRC) has been involved in the research and development of high speed flywheel systems for small satellite energy storage and attitude control applications. One research and development area has been the minimization of the switching noise produced by the pulsed width modulated (PWM) inverter that drives the flywheel permanent magnet motor/generator (PM M/G). This noise can interfere with the flywheel M/G hardware and the system avionics hampering the full speed performance of the flywheel system. One way to attenuate the inverter switching noise is by placing an AC filter at the three phase output terminals of the inverter with the filter neutral point connected to the DC link (DC bus) midpoint capacitors. The main benefit of using an AC filter in this fashion is the significant reduction of the inverter s high dv/dt switching and its harmonics components. Additionally, common mode (CM) and differential mode (DM) voltages caused by the inverter s high dv/dt switching are also reduced. Several topologies of AC filters have been implemented and compared. One AC filter topology consists of a two-stage R-L-C low pass filter. The other topology consists of the same two-stage R-L-C low pass filter with a series connected trap filter (an inductor and capacitor connected in parallel). This paper presents the analysis, design and experimental results of these AC filter topologies and the comparison between the no filter case and conventional AC filter.

  3. Self-driving carsickness.

    Science.gov (United States)

    Diels, Cyriel; Bos, Jelte E

    2016-03-01

    This paper discusses the predicted increase in the occurrence and severity of motion sickness in self-driving cars. Self-driving cars have the potential to lead to significant benefits. From the driver's perspective, the direct benefits of this technology are considered increased comfort and productivity. However, we here show that the envisaged scenarios all lead to an increased risk of motion sickness. As such, the benefits this technology is assumed to bring may not be capitalised on, in particular by those already susceptible to motion sickness. This can negatively affect user acceptance and uptake and, in turn, limit the potential socioeconomic benefits that this emerging technology may provide. Following a discussion on the causes of motion sickness in the context of self-driving cars, we present guidelines to steer the design and development of automated vehicle technologies. The aim is to limit or avoid the impact of motion sickness and ultimately promote the uptake of self-driving cars. Attention is also given to less well known consequences of motion sickness, in particular negative aftereffects such as postural instability, and detrimental effects on task performance and how this may impact the use and design of self-driving cars. We conclude that basic perceptual mechanisms need to be considered in the design process whereby self-driving cars cannot simply be thought of as living rooms, offices, or entertainment venues on wheels. Copyright © 2015 Elsevier Ltd and The Ergonomics Society. All rights reserved.

  4. Above- and below-ground effects of plant diversity depend on species origin

    DEFF Research Database (Denmark)

    Kuebbing, Sara E.; Classen, Aimee Taylor; Sanders, Nate

    2015-01-01

    -interaction models to describe how species' interactions influenced diversity-productivity relationships. Communities with more species had higher total biomass than did monoculture communities, but native and nonnative communities diverged in root : shoot ratios and the mechanism responsible for increased......Although many plant communities are invaded by multiple nonnative species, we have limited information on how a species' origin affects ecosystem function. We tested how differences in species richness and origin affect productivity and seedling establishment. We created phylogenetically paired...... native and nonnative plant communities in a glasshouse experiment to test diversity-productivity relationships and responsible mechanisms (i.e. selection or complementarity effects). Additionally, we tested how productivity and associated mechanisms influenced seedling establishment. We used diversity...

  5. The effect of urbanization on ant abundance and diversity: a temporal examination of factors affecting biodiversity.

    Directory of Open Access Journals (Sweden)

    Grzegorz Buczkowski

    Full Text Available Numerous studies have examined the effect of urbanization on species richness and most studies implicate urbanization as the major cause of biodiversity loss. However, no study has identified an explicit connection between urbanization and biodiversity loss as the impact of urbanization is typically inferred indirectly by comparing species diversity along urban-rural gradients at a single time point. A different approach is to focus on the temporal rather than the spatial aspect and perform "before and after" studies where species diversity is cataloged over time in the same sites. The current study examined changes in ant abundance and diversity associated with the conversion of natural habitats into urban habitats. Ant abundance and diversity were tracked in forested sites that became urbanized through construction and were examined at 3 time points - before, during, and after construction. On average, 4.3 ± 1.2 unique species were detected in undisturbed plots prior to construction. Ant diversity decreased to 0.7 ± 0.8 species in plots undergoing construction and 1.5 ± 1.1 species in plots 1 year after construction was completed. With regard to species richness, urbanization resulted in the permanent loss of 17 of the 20 species initially present in the study plots. Recovery was slow and only 3 species were present right after construction was completed and 4 species were present 1 year after construction was completed. The second objective examined ant fauna recovery in developed residential lots based on time since construction, neighboring habitat quality, pesticide inputs, and the presence of invasive ants. Ant diversity was positively correlated with factors that promoted ecological recovery and negatively correlated with factors that promoted ecological degradation. Taken together, these results address a critical gap in our knowledge by characterizing the short- and long-term the effects of urbanization on the loss of ant

  6. The effect of urbanization on ant abundance and diversity: a temporal examination of factors affecting biodiversity.

    Science.gov (United States)

    Buczkowski, Grzegorz; Richmond, Douglas S

    2012-01-01

    Numerous studies have examined the effect of urbanization on species richness and most studies implicate urbanization as the major cause of biodiversity loss. However, no study has identified an explicit connection between urbanization and biodiversity loss as the impact of urbanization is typically inferred indirectly by comparing species diversity along urban-rural gradients at a single time point. A different approach is to focus on the temporal rather than the spatial aspect and perform "before and after" studies where species diversity is cataloged over time in the same sites. The current study examined changes in ant abundance and diversity associated with the conversion of natural habitats into urban habitats. Ant abundance and diversity were tracked in forested sites that became urbanized through construction and were examined at 3 time points - before, during, and after construction. On average, 4.3 ± 1.2 unique species were detected in undisturbed plots prior to construction. Ant diversity decreased to 0.7 ± 0.8 species in plots undergoing construction and 1.5 ± 1.1 species in plots 1 year after construction was completed. With regard to species richness, urbanization resulted in the permanent loss of 17 of the 20 species initially present in the study plots. Recovery was slow and only 3 species were present right after construction was completed and 4 species were present 1 year after construction was completed. The second objective examined ant fauna recovery in developed residential lots based on time since construction, neighboring habitat quality, pesticide inputs, and the presence of invasive ants. Ant diversity was positively correlated with factors that promoted ecological recovery and negatively correlated with factors that promoted ecological degradation. Taken together, these results address a critical gap in our knowledge by characterizing the short- and long-term the effects of urbanization on the loss of ant biodiversity.

  7. Effects of Different Types of Cognitive Training on Cognitive Function, Brain Structure, and Driving Safety in Senior Daily Drivers: A Pilot Study

    OpenAIRE

    Nozawa, Takayuki; Taki, Yasuyuki; Kanno, Akitake; Akimoto, Yoritaka; Ihara, Mizuki; Yokoyama, Ryoichi; Kotozaki, Yuka; Nouchi, Rui; Sekiguchi, Atsushi; Takeuchi, Hikaru; Miyauchi, Carlos Makoto; Ogawa, Takeshi; Goto, Takakuni; Sunda, Takashi; Shimizu, Toshiyuki

    2015-01-01

    Background. Increasing proportion of the elderly in the driving population raises the importance of assuring their safety. We explored the effects of three different types of cognitive training on the cognitive function, brain structure, and driving safety of the elderly. Methods. Thirty-seven healthy elderly daily drivers were randomly assigned to one of three training groups: Group V trained in a vehicle with a newly developed onboard cognitive training program, Group P trained with a simil...

  8. More diversity, less tolerance? The effect of type of cultural diversity on the erosion of tolerance in Swiss municipalities

    DEFF Research Database (Denmark)

    Rapp, Carolin

    2015-01-01

    Immigration and the ways in which host societies receive newcomers pose challenges for modern civil societies. This article contributes to the ongoing discussion about how ethnic diversity influences tolerance towards immigrants. Compared to previous studies, we analyse tolerance as a sequential ...

  9. Electric drives

    Energy Technology Data Exchange (ETDEWEB)

    1986-10-01

    Several electric vehicles have been tested in long-term tests, i.e. an electric passenger car (maximum speed 115 km/h) and several busses for use in pedestrians' zones, spas, airports, natural reserves, and urban transportation (DUO busses). The ICE high-speed train is discussed in some detail, i.e. its aeroacoustic and aerodynamic design, running gear, computer-controlled drives and brakes, diagnostic systems, and electrical equipment. The Berlin Maglev system is mentioned as well as current inverters in rail vehicles. (HWJ).

  10. Habitat Fragmentation Drives Plant Community Assembly Processes across Life Stages

    Science.gov (United States)

    Hu, Guang; Feeley, Kenneth J.; Yu, Mingjian

    2016-01-01

    Habitat fragmentation is one of the principal causes of biodiversity loss and hence understanding its impacts on community assembly and disassembly is an important topic in ecology. We studied the relationships between fragmentation and community assembly processes in the land-bridge island system of Thousand Island Lake in East China. We focused on the changes in species diversity and phylogenetic diversity that occurred between life stages of woody plants growing on these islands. The observed diversities were compared with the expected diversities from random null models to characterize assembly processes. Regression tree analysis was used to illustrate the relationships between island attributes and community assembly processes. We found that different assembly processes predominate in the seedlings-to-saplings life-stage transition (SS) vs. the saplings-to-trees transition (ST). Island area was the main attribute driving the assembly process in SS. In ST, island isolation was more important. Within a fragmented landscape, the factors driving community assembly processes were found to differ between life stage transitions. Environmental filtering had a strong effect on the seedlings-to-saplings life-stage transition. Habitat isolation and dispersal limitation influenced all plant life stages, but had a weaker effect on communities than area. These findings add to our understanding of the processes driving community assembly and species coexistence in the context of pervasive and widespread habitat loss and fragmentation. PMID:27427960

  11. Effect of Maryland's 2011 Alcohol Sales Tax Increase on Alcohol-Positive Driving.

    Science.gov (United States)

    Lavoie, Marie-Claude; Langenberg, Patricia; Villaveces, Andres; Dischinger, Patricia C; Simoni-Wastila, Linda; Hoke, Kathleen; Smith, Gordon S

    2017-07-01

    The 2011 Maryland alcohol sales tax increase from 6% to 9% provided an opportunity to evaluate the impact on rates of alcohol-positive drivers involved in injury crashes. Maryland police crash reports from 2001 to 2013 were analyzed using an interrupted time series design and a multivariable analysis employing generalized estimating equations models with a negative binomial distribution. Data were analyzed in 2014-2015. There was a significant gradual annual reduction of 6% in the population-based rate of all alcohol-positive drivers (ptax increase. There were no significant changes in rates of alcohol-positive drivers aged 35-54 years (rate ratio, 0.98; 95% CI=0.89, 1.09). Drivers aged ≥55 years had a significant immediate 10% increase in the rate of alcohol-positive drivers (rate ratio, 1.10; 95% CI=1.04, 1.16) and a gradual increase of 4.8% per year after the intervention. Models using different denominators and controlling for multiple factors including a proxy for unmeasured factors found similar results overall. The 2011 Maryland alcohol sales tax increase led to a significant reduction in the rate of all alcohol-positive drivers involved in injury crashes especially among drivers aged 15-34 years. This is the first study to examine the impact of alcohol sales taxes on crashes; previous research focused on excise tax. Increasing alcohol taxes is an important but often neglected intervention to reduce alcohol-impaired driving. Copyright © 2017 American Journal of Preventive Medicine. Published by Elsevier Inc. All rights reserved.

  12. Effects of Fatigue on Driving Safety: A Comparison of Brake Reaction Times in Night Float and Postcall Physicians in Training.

    Science.gov (United States)

    Talusan, Paul G; Long, Theodore; Halim, Andrea; Guliani, Laura; Carroll, Nicole; Reach, John

    2014-12-01

    Concerns about duty hour and resident safety have fostered discussion about postshift fatigue and driving impairment. We assessed how converting to a night float schedule for overnight coverage affected driving safety for trainees. Brake reaction times were measured for internal medicine and orthopaedic surgery resident volunteers after a traditional 28-hour call shift and after a night float shift. We conducted matched paired t tests of preshift and postshift reaction time means. Participants also completed the Epworth Sleepiness Scale pre- and postshift. From June to July 2013, we enrolled 58 interns and residents (28 orthopaedic surgery, 30 internal medicine). We included 24 (41%) trainees on night float rotations and 34 (59%) trainees on traditional 28-hour call shifts. For all residents on night float rotations, there was no significant difference pre- and postshift. An increase in reaction times was noted among trainees on 28-hour call rotations. This included no effect on reaction times for internal medicine trainees pre- and postshift, and an increase in reaction times for orthopaedic trainees. For both night float and traditional call groups, there were significant increases in the Epworth Sleepiness Scale. Trainees on traditional 28-hour call rotations had significantly worse postshift brake reaction times, whereas trainees on night float rotations had no difference. Orthopaedic trainees had significant differences in brake reaction times after a traditional call shift.

  13. Effects of in-vehicle warning information displays with or without spatial compatibility on driving behaviors and response performance.

    Science.gov (United States)

    Liu, Yung-Ching; Jhuang, Jing-Wun

    2012-07-01

    A driving simulator study was conducted to evaluate the effects of five in-vehicle warning information displays upon drivers' emergent response and decision performance. These displays include visual display, auditory displays with and without spatial compatibility, hybrid displays in both visual and auditory format with and without spatial compatibility. Thirty volunteer drivers were recruited to perform various tasks that involved driving, stimulus-response, divided attention and stress rating. Results show that for displays of single-modality, drivers benefited more when coping with visual display of warning information than auditory display with or without spatial compatibility. However, auditory display with spatial compatibility significantly improved drivers' performance in reacting to the divided attention task and making accurate S-R task decision. Drivers' best performance results were obtained for hybrid display with spatial compatibility. Hybrid displays enabled drivers to respond the fastest and achieve the best accuracy in both S-R and divided attention tasks. Copyright © 2011 Elsevier Ltd and The Ergonomics Society. All rights reserved.

  14. Cognitive impairment and driving safety.

    Science.gov (United States)

    Eby, David W; Molnar, Lisa J

    2012-11-01

    As the populations of many countries continue to age, cognitive impairment will likely become more common. Individuals with cognitive impairment pose special challenges for families, health professionals, driving safety professionals, and the larger community, particularly if these older adults depend on driving as their primary means of community mobility. It is vital that we continue to extend our knowledge about the driving behavior of individuals' with cognitive impairment, as well as try to develop effective means of screening and assessing these individuals for fitness to drive and help facilitate their transition to non-driving when appropriate. This special issue is intended to provide researchers and practitioners an opportunity to present the most recent research findings on driving-related issues among older adults with cognitive impairment. The issue contains 11 original contributions from seven countries. The topics covered by these papers are: crash risks; screening, assessment, and fitness to drive; driving performance using a driving simulator; and driving behaviors and driving-related decisions of people with cognitive impairments. Copyright © 2012. Published by Elsevier Ltd.

  15. Woody species diversity in forest plantations in a mountainous region of Beijing, China: effects of sampling scale and species selection.

    Directory of Open Access Journals (Sweden)

    Yuxin Zhang

    Full Text Available The role of forest plantations in biodiversity conservation has gained more attention in recent years. However, most work on evaluating the diversity of forest plantations focuses only on one spatial scale; thus, we examined the effects of sampling scale on diversity in forest plantations. We designed a hierarchical sampling strategy to collect data on woody species diversity in planted pine (Pinus tabuliformis Carr., planted larch (Larix principis-rupprechtii Mayr., and natural secondary deciduous broadleaf forests in a mountainous region of Beijing, China. Additive diversity partition analysis showed that, compared to natural forests, the planted pine forests had a different woody species diversity partitioning pattern at multi-scales (except the Simpson diversity in the regeneration layer, while the larch plantations did not show multi-scale diversity partitioning patterns that were obviously different from those in the natural secondary broadleaf forest. Compare to the natural secondary broadleaf forests, the effects of planted pine forests on woody species diversity are dependent on the sampling scale and layers selected for analysis. Diversity in the planted larch forest, however, was not significantly different from that in the natural forest for all diversity components at all sampling levels. Our work demonstrated that the species selected for afforestation and the sampling scales selected for data analysis alter the conclusions on the levels of diversity supported by plantations. We suggest that a wide range of scales should be considered in the evaluation of the role of forest plantations on biodiversity conservation.

  16. Investigating Effects of Participatory Range Management Plans on Species Diversity in Semirum-Isfahan Province

    Directory of Open Access Journals (Sweden)

    M. Borhani

    2016-05-01

    Full Text Available In order to investigate the effects of range management plans on species diversity, richness and evenness in Semirum rangelands, 52 sites (28 with treated plan and 24 without treated plan were selected. The non-parametric indices for species richness (Margalof, Menhinick, Jacknife and counting method and species diversity (Simpson, Camargo, Smith and Wilson and modified Nee were compared in two management plans. The mean comparisons were made by independent T Student Test and Mann-Witheny U Test, and correlation was determined between diversity indices and vegetation parameters. Based on the results there was no significant difference between the two management systems regarding environmental features, while the implementation of range management plans caused significant reduction of stocking rate. Among the studied indices, evenness of species in sites without treated plan was significantly more than the sites with treated plan. The correlation matrix showed that there was a significant positive correlation between species richness and vegetation cover, production of perennial plans, and the rangeland condition and trend, while evenness showed significant negative correlation with these indices. Generally, implementation of range management plans has considerable effect on increasing climax species, dominance of Bromus tomentellus and it causes improvement of rangeland condition and reduction of evenness. This behavior could be explained by the balance between species competition and grazing pressure. Further, succession process of the studied communities demonstrates domination of some desirable species, high production and less diversity.

  17. Effect of bile diversion on satiety and fat absorption from liquid and solid dietary sources

    International Nuclear Information System (INIS)

    Doty, J.E.; Gu, Y.G.; Meyer, J.H.

    1988-01-01

    In previous studies, liquid fat has been used to determine the effect of bile diversion on fat absorption. Since protein digests, in addition to bile salts, are capable of solubilizing lipids, we hypothesized that fat incorporated in the protein-rich matrix of solid food would be less sensitive to bile diversion than fat ingested as an oil or liquid. Using [3H]glycerol triether as a nonabsorbable fat recovery marker, we determined how much [14C]triolein was absorbed from solid (chicken liver) and liquid (margarine) dietary sources. After a standard liquid/solid meal with either the chicken liver or margarine labeled, midintestinal chyme was collected for 6 hr, extracted, and counted for 14C and 3H activity. Zero, eighty, or one hundred percent of endogenous bile was diverted. Fat absorption from both chicken liver and margarine was nearly complete by midintestine with 0% diversion and was little affected by diversion of 80% of bile. Complete biliary diversion significantly decreased fat absorption from margarine (87.9 +/- 4.4 to 37.2 +/- 9.2%, P less than 0.05) but reduced [14C]triolein absorption from chicken liver less consistently and insignificantly (78.8 +/- 6.9 to 43.9 +/- 10.6%). These data indicate that fat absorption is not solely dependent on bile and support the hypothesis that fat ingested in a cellular matrix is less dependent on bile than liquid fat. Using these same animals but with the midintestinal cannulas plugged to expose the distal intestine to unabsorbed luminal nutrients, we also demonstrated that bile diversion of an initial meal reduced food consumption at a meal offered 3 hr later

  18. Driving decisions when leaving electronic music dance events: driver, passenger, and group effects.

    Science.gov (United States)

    Johnson, Mark B; Voas, Robert B; Miller, Brenda A

    2012-01-01

    The goal of this article was to identify characteristics of drivers and passengers that predicted peer groups whose drivers exit dance clubs with alcohol levels indicative of impairment (blood alcohol content [BAC] ≥ 0.05 g/dL). We used the portal survey methodology to randomly sample groups of electronic music dance event (EMDE) patrons as they entered and exited a club. From May through November 2010, data were collected from 38 EMDEs hosted by 8 clubs in the San Francisco Bay area. Data included in these analyses are results from breath samples for measuring BAC and self-report data on demographics, recent drinking history drinking, drinking intentions, travel to and from the clubs, and the familiarity/experience with other group members. These data were collected from a subset of 175 drivers and 272 passengers. Although drivers drank less than passengers, one driver in 5 groups had a BAC indicative of elevated crash risk (BAC ≥ 0.05 g/dL). Groups of drivers and/or passengers with a recent history of binge drinking were more likely to have drivers with BACs ≥ 0.05 g/dL. One unanticipated finding was that drivers who knew more group members relatively well were more likely to exit the club with a BAC ≥ 0.05 g/dL. Additionally, we found that groups with all female passengers were at greater risk for having a driver whose BAC was ≥ 0.05 g/dL. Some group characteristics predicted drivers who exit clubs with BACs ≥ 0.05 g/dL. One intervention strategy to promote safety might be to encourage group members to reconsider who is sober enough to drive away from the club; for some groups, a change of drivers would be a safer choice, because a passenger may have a relatively safe BAC. Groups of females appear to have a particularly elevated risk of having a driver whose BAC exceeds 0.05 g/dL, and new intervention efforts should be particularly directed to these at-risk groups.

  19. Control rod drive

    International Nuclear Information System (INIS)

    Hawke, B.C.

    1986-01-01

    A reactor core, one or more control rods, and a control rod drive are described for selectively inserting and withdrawing the one or more control rods into and from the reactor core, which consists of: a support structure secured beneath the reactor core; control rod positioning means supported by the support structure for movably supporting the control rod for movement between a lower position wherein the control rod is located substantially beneath the reactor core and an upper position wherein at least an upper portion of the control rod extends into the reactor core; transmission means; primary drive means connected with the control rod positioning means by the transmission means for positioning the control rod under normal operating conditions; emergency drive means for moving the control rod from the lower position to the upper position under emergency conditions, the emergency drive means including a weight movable between an upper and a lower position, means for movably supporting the weight, and means for transmitting gravitational force exerted on the weight to the control rod positioning means to move the control rod upwardly when the weight is pulled downwardly by gravity; the transmission means connecting the control rod positioning means with the emergency drive means so that the primary drive means effects movement of the weight and the control rod in opposite directions under normal conditions, thus providing counterbalancing to reduce the force required for upward movement of the control rod under normal conditions; and restraint means for restraining the fall of the weight under normal operating conditions and disengaging the primary drive means to release the weight under emergency conditions

  20. Nitrogen availability drives priming effect by altering microbial carbon-use efficiency after permafrost thaw

    Science.gov (United States)

    Chen, L.; Liu, L.; Zhang, Q.; Mao, C.; Liu, F.; Yang, Y.

    2017-12-01

    Enhanced vegetation growth can potentially aggravate soil C loss by accelerating the decomposition of soil organic matter (SOM) ("priming effect"), thereby reinforcing the positive C-climate feedback in permafrost ecosystems. However, the degree to which priming effect alters permafrost C dynamics is expected to be modified by nitrogen (N) availability after permafrost thaw. Despite this recognition, experimental evidence for the linkage between priming effect and post-thaw N availability is still lacking. Particularly, the microbial mechanisms involved remain unknown. Here, using a thermokarst-induced natural N gradient combined with an isotope-labeled glucose and N addition experiment, we presented a strong linkage between soil N availability and priming effect in Tibetan permafrost. We observed that the magnitude of priming effect along the thaw gradient was negatively associated with soil total dissolved nitrogen (TDN) concentration. This negative effect of post-thaw N availability was further proved by a sharply reduced priming effect following mineral N supply. These two lines of evidence jointly illustrated that the priming effect along the thaw chronosequence was controlled by N availability, supporting the `N mining theory'. In contrast to the prevailing assumption, this N-regulated priming effect was independent from changes in C- or N-acquiring enzyme activities, but positively associated with the change in metabolic quotients (△SOM-qCO2), highlighting that decreased microbial metabolism efficiency rather than increased enzyme activities account for greater priming effect under reduced N availability. Taken together, these findings demonstrate that C dynamics in melting permafrost largely depends on post-thaw N availability due to its effect of retarding SOM mineralization. This C-N interaction and the relevant microbial metabolic efficiency should be considered in Earth System Models for a better understanding of soil C dynamics after permafrost thaw.

  1. Safe driving for teens

    Science.gov (United States)

    Driving and teenagers; Teens and safe driving; Automobile safety - teenage drivers ... months before taking friends as passengers. Teenage-related driving deaths occur more often in certain conditions. OTHER SAFETY TIPS FOR TEENS Reckless driving is still a ...

  2. Effects of timber harvest on structural diversity and species composition in hardwood forests

    Directory of Open Access Journals (Sweden)

    FARZAM TAVANKAR

    2015-04-01

    Full Text Available Tavankar F, Bonyad AE. 2015. Effects of timber harvest on structural diversity and species composition in hardwood forests. Biodiversitas 16: 1-9. Forest management leads to changes in structure and species composition of stands. In this research vertical and horizontal structure and species composition were compared in two harvested and protected stands in the Caspian forest of Iran. The results indicated the tree and seedling density, total basal area and stand volume was significantly (P < 0.01 higher in the protected stand. The Fagus orientalis L. had the most density and basal area in the both stands. Species importance value (SIV of Fagus orientalis in the protected stand (92.5 was higher than in the harvested stand (88.5. While, the SIV of shade-intolerant tree species such as Acer insigne, Acer cappadocicum and Alnus subcordata was higher in the harvested stand. The density of trees and seedling of rare tree species, such as Ulmus glabra, Tilia begonifolia, Zelkova caprinifolia and Fraxinus coriarifolia, was also higher in the protected stand. The Shannon-Wiener diversity index in the protected stand (0.84 was significantly higher (P < 0.01 than in the harvested stand (0.72. The highest diversity value in the harvested stand was observed in DBH of 10-40 cm class, while DBH of 40-70 cm had the highest diversity value in the protected stand.

  3. Acacia sieberiana Effects on Soil Properties and Plant Diversity in Songa Pastures, Rwanda

    Directory of Open Access Journals (Sweden)

    C. P. Mugunga

    2013-01-01

    Full Text Available Effects of A. sieberiana trees on soil properties and plant diversity were investigated in Songa pastures, Rwanda. Tree characteristics and crown architecture of A. sieberiana were studied. Soil properties were assessed and plants were identified under and away from tree crowns. Counts of individual plants/species were done only under tree crowns. Nitrogen, P, and K were analysed in the soil, grass, and A. sieberiana leaves. Plant diversity was determined using Simpson's diversity index. Data were subjected to ANOVA. Soil organic carbon (SOC, cation exchange capacity (CEC, Ca2+, N and pH, and plant diversity were higher in soils under tree canopies than in open areas. Tree leaves were significantly richer in N and poorer in P and K as compared to grasses. Tree crowns grew wider and horizontal and developed intertwined secondary branching, reducing light intensity to as low as 38% under tree canopies compared to the open pasture. At 3 trees/ha stocking, A. sieberiana trees shaded 0.18 ha and herbaceous plants and grasses unpalatable to livestock dominated under tree canopies. A tradeoff of A. sieberiana tree value versus the loss of palatable grass due to tree presence needs to be assessed to decide whether the trees should be included in pastures and if yes, the apporpriate stocking identified.

  4. Spider fauna of semiarid eastern Colorado agroecosystems: diversity, abundance, and effects of crop intensification.

    Science.gov (United States)

    Kerzicnik, Lauren M; Peairs, Frank B; Cushing, Paula E; Draney, Michael L; Merrill, Scott C

    2013-02-01

    Spiders are critical predators in agroecosystems. Crop management practices can influence predator density and diversity, which, in turn, can influence pest management strategies. Crop intensification is a sustainable agricultural technique that can enhance crop production although optimizing soil moisture. To date, there is no information on how crop intensification affects natural enemy populations, particularly spiders. This study had two objectives: to characterize the abundance and diversity of spiders in eastern Colorado agroecosystems, and to test the hypothesis that spider diversity and density would be higher in wheat (Triticum aestivum L.) in crop-intensified rotations compared with wheat in conventional rotations. We collected spiders through pitfall, vacuum, and lookdown sampling from 2002 to 2007 to test these objectives. Over 11,000 spiders in 19 families from 119 species were captured from all sampling techniques. Interestingly, the hunting spider guild represented 89% of the spider fauna captured from all sites with the families Gnaphosidae and Lycosidae representing 75% of these spiders. Compared with European agroecosystems, these agroecosystems had greater diversity, which can be beneficial for the biological control of pests. Overall, spider densities were low in these semiarid cropping systems, and crop intensification effects on spider densities were not evident at this scale.

  5. The effects of plant diversity on nitrous oxide emissions in hydroponic microcosms

    Science.gov (United States)

    Sun, Hongying; Zhang, Chongbang; Song, Changchun; Chang, Scott X.; Gu, Baojing; Chen, Zhengxin; Peng, Changhui; Chang, Jie; Ge, Ying

    2013-10-01

    Previous studies have shown that plant diversity can improve the wastewater purification efficiency of constructed wetlands (CWs), but its effect on the nitrous oxide (N2O) emission in CWs has been unknown. To investigate the effect of plant diversity on the N2O emission, we established four plant species richness levels (each level containing 1, 2, 3 and 4 species, respectively) by using 96 hydroponic microcosms. Results showed that plant species richness enhanced the N2O emission, ranging from 27.1 to 115.4 μg N2O m-2 d-1, and improved nitrate removal (P 0.05), but improved nitrogen removal (P < 0.001). Hence, our study highlights the importance of both plant species richness and species identity in mediating the N2O emission and nitrogen removal in CWs.

  6. A Study of the Effect of the Fringe Fields on the Electrostatic Force in Vertical Comb Drives

    Directory of Open Access Journals (Sweden)

    Else Gallagher

    2014-10-01

    Full Text Available The equation that describes the relationship between the applied voltage and the resulting electrostatic force within comb drives is often used to assist in choosing the dimensions for their design. This paper re-examines how some of these dimensions—particularly the cross-sectional dimensions of the comb teeth—affect this relationship in vertical comb drives. The electrostatic forces in several vertical comb drives fabricated for this study were measured and compared to predictions made with four different mathematical models in order to explore the amount of complexity required within a model to accurately predict the electrostatic forces in the comb drives.

  7. Epiphytic lichen diversity in central European oak forests: Assessment of the effects of natural environmental factors and human influences

    International Nuclear Information System (INIS)

    Svoboda, David; Peksa, Ondrej; Vesela, Jana

    2010-01-01

    We investigated lichen diversity in temperate oak forests using standardized protocols. Forty-eight sites were sampled in the Czech Republic, Slovakia and Hungary. The effects of natural environmental predictors and human influences on lichen diversity (lichen diversity value, species richness) were analysed by means of correlation tests. We found that lichen diversity responded differently to environmental predictors between two regions with different human impact. In the industrial region, air pollution was the strongest factor. In the agricultural to highly forested regions, lichen diversity was strongly influenced by forest age and forest fragmentation. We found that several natural factors can in some cases obscure the effect of human influences. Thus, factors of naturality gradient must be considered (both statistically and interpretively) when studying human impact on lichen diversity. - We detected the different responses of lichens to ecological predictors in polluted and unpolluted areas.

  8. Analysis of effects of geological structures in rock driving by TBM

    Directory of Open Access Journals (Sweden)

    Ľudmila Tréfová

    2006-12-01

    Full Text Available Although mechanical properties belongs to important parameter for the excavation modelling, effect of geological structures on the rock massive fragmentation is often much higher than varying rock properties. This paper deals with the analysis of geological structures. It is focused on the schistosity orientation towards the tunnel azimuth. The aim is to define of schistosity effect on the penetration rate. It is a basis creating of fuzzy rules for the performance model full-profile tunnel boring machine

  9. A Simplified Analytic Investigation of the Riverside Effects of Sediment Diversions

    Science.gov (United States)

    2013-09-01

    demonstrated that the river bed consists of a sand layer of variable thickness, underlain by erosion resistant strata (either relict glacial deposits...following analysis. Simplifications and Initial Conditions. Consider a river modeled as a wide rectangular channel of constant width (Figure 1). The...CHETN-VII-13 September 2013 14  Short term effects include the redistribution of sediment by erosion upstream of the diversion to deposition

  10. Downstream wind flow path diversion and its effects on the performance of vertical axis wind turbine

    International Nuclear Information System (INIS)

    Maganhar, A.L.

    2015-01-01

    In the present experimental study efforts have been made to analysis path diversion effect of downstream wind flow on performance of vertical axis wind turbine (VAWT). For the blockage of downstream wind flow path at various linear displaced positions, a normal erected flat wall, semi-circular and cylindrical shapes were tested for path diverting geometries. Performance of VAWT in terms of improved rotor speed up to 45% was achieved. (author)

  11. The Effect of Urbanization on Ant Abundance and Diversity: A Temporal Examination of Factors Affecting Biodiversity

    OpenAIRE

    Buczkowski, Grzegorz; Richmond, Douglas S.

    2012-01-01

    Numerous studies have examined the effect of urbanization on species richness and most studies implicate urbanization as the major cause of biodiversity loss. However, no study has identified an explicit connection between urbanization and biodiversity loss as the impact of urbanization is typically inferred indirectly by comparing species diversity along urban-rural gradients at a single time point. A different approach is to focus on the temporal rather than the spatial aspect and perform "...

  12. The Hayflick Limit May Determine the Effective Clonal Diversity of Naive T Cells.

    Science.gov (United States)

    Ndifon, Wilfred; Dushoff, Jonathan

    2016-06-15

    Having a large number of sufficiently abundant T cell clones is important for adequate protection against diseases. However, as shown in this paper and elsewhere, between young adulthood and >70 y of age the effective clonal diversity of naive CD4/CD8 T cells found in human blood declines by a factor of >10. (Effective clonal diversity accounts for both the number and the abundance of T cell clones.) The causes of this observation are incompletely understood. A previous study proposed that it might result from the emergence of certain rare, replication-enhancing mutations in T cells. In this paper, we propose an even simpler explanation: that it results from the loss of T cells that have attained replicative senescence (i.e., the Hayflick limit). Stochastic numerical simulations of naive T cell population dynamics, based on experimental parameters, show that the rate of homeostatic T cell proliferation increases after the age of ∼60 y because naive T cells collectively approach replicative senescence. This leads to a sharp decline of effective clonal diversity after ∼70 y, in agreement with empirical data. A mathematical analysis predicts that, without an increase in the naive T cell proliferation rate, this decline will occur >50 yr later than empirically observed. These results are consistent with a model in which exhaustion of the proliferative capacity of naive T cells causes a sharp decline of their effective clonal diversity and imply that therapeutic potentiation of thymopoiesis might either prevent or reverse this outcome. Copyright © 2016 by The American Association of Immunologists, Inc.

  13. A simultaneous description of fast wave e-TTMP and ion current drive effects on shear in a tokamak: theory and experiments in JET

    International Nuclear Information System (INIS)

    Bhatnagar, V.P.; Bosia, G.; Jacquinot, J.; Porcelli, F.

    1993-01-01

    A controlled local modification of the plasma-current profile, the safety factor q or shear (dq/dr) in a tokamak can lead to an improvement in its performance. For example, enhanced confinement in JET discharges with deep pellet injection is found to be associated with a reversal of the shear. Also, a significant control over the sawteeth behaviour in the JET tokamak has been found to occur when the shear at the q = 1 surface is modified by a dipolar-current driven by ICRF in the minority-ion heating regime. This could give a handle on the ejection of fast particles and hence on burn control in a reactor. The above sawtooth control may also be used to ease the ash removal in a reactor. When an ICRH antenna array is phased (Δφ ≠ 0 or π), the excited asymmetric k // -spectrum can drive non inductive currents by interaction of waves both with electrons (TTMP and e-Landau damping) and ions at minority (fundamental) or harmonic cyclotron resonances depending upon the scenario. Therefore, in any modeling of ICRF current drive, both (electron and ion) current drive mechanisms must be included simultaneously to correctly represent the non inductive current drive profile. To devise scenarios of shear control by minority current drive, that take advantage of the inherent electron current drive as well, we have developed a model based on earlier theories to calculate, for the first time, the two effects simultaneously. (author) 11 refs., 5 figs

  14. [Attention diversion in tinnitus therapy. Comparison of the effects of different treatment methods].

    Science.gov (United States)

    Eysel-Gosepath, K; Gerhards, F; Schicketanz, K-H; Teichmann, K; Benthien, M

    2004-05-01

    Diversion or distraction of auditory attention is a core principle of tinnitus retraining therapy as introduced by P. Jastreboff and J. Hazell. The aim of this study was to evaluate the effectiveness of a different form of attention diversion in tinnitus therapy. In a prospective and randomized study, 40 patients suffering from chronic tinnitus were assigned to two different groups, A or B. All patients received appropriate counselling and were instructed in relaxation training. Patients in group A learned to distract attention away from the tinnitus by using sound or music. White noise generators or hearing aids were applied in this group. Patients in group B were instructed to direct their attention away from the tinnitus using imagination that was facilitated by the use of light and warmth stimuli as distracters. Different standardized questionnaires were used for an evaluation of therapy effectiveness. In both groups, patients were significantly less annoyed and disabled by their tinnitus immediately after therapy and after 6 months. Tinnitus annoyance still proved to be reduced 1 year after the end of the therapy. There were no significant differences in the effects of each treatment. Attention diversion is an important method for decreasing tinnitus-related distress. Patients should be instructed to use not only auditory but also visual and thermal sensations in order to distract attention away from their tinnitus.

  15. Organic, integrated and conventional management in apple orchards: effect on plant species composition, richness and diversity

    Directory of Open Access Journals (Sweden)

    Zdeňka Lososová

    2011-01-01

    Full Text Available The study was conducted to assess the effect of conventional, integrated and organic management on differences in plant species composition, richness and diversity. The plants were studied in triads of orchards situated in three regions of the Czech Republic. Data about species occurrences were collected on 15 permanent plots in the tree rows and 15 plots between tree rows in each of the apple orchards during 2009. A total of 201 vascular plant species (127 native species, 65 archaeophytes, and 9 neophytes were found. Management type and also different regional conditions had a significant effect on plant species composition and on diversity parameters of orchard spontaneous vegetation. Species richness and species pool was significantly higher in the organic orchards than in the differently managed orchards. Management type had significant effect on proportions of archaeophytes, and also neophytes in apple orchards. The results showed that a change from conventional to integrated and organic management in apple orchards lead to higher plant species diversity and to changes in plant species composition.

  16. Cross-scale analysis of the region effect on vascular plant species diversity in southern and northern European mountain ranges.

    Directory of Open Access Journals (Sweden)

    Jonathan Lenoir

    Full Text Available BACKGROUND: The divergent glacial histories of southern and northern Europe affect present-day species diversity at coarse-grained scales in these two regions, but do these effects also penetrate to the more fine-grained scales of local communities? METHODOLOGY/PRINCIPAL FINDINGS: We carried out a cross-scale analysis to address this question for vascular plants in two mountain regions, the Alps in southern Europe and the Scandes in northern Europe, using environmentally paired vegetation plots in the two regions (n = 403 in each region to quantify four diversity components: (i total number of species occurring in a region (total γ-diversity, (ii number of species that could occur in a target plot after environmental filtering (habitat-specific γ-diversity, (iii pair-wise species compositional turnover between plots (plot-to-plot β-diversity and (iv number of species present per plot (plot α-diversity. We found strong region effects on total γ-diversity, habitat-specific γ-diversity and plot-to-plot β-diversity, with a greater diversity in the Alps even towards distances smaller than 50 m between plots. In contrast, there was a slightly greater plot α-diversity in the Scandes, but with a tendency towards contrasting region effects on high and low soil-acidity plots. CONCLUSIONS/SIGNIFICANCE: We conclude that there are strong regional differences between coarse-grained (landscape- to regional-scale diversity components of the flora in the Alps and the Scandes mountain ranges, but that these differences do not necessarily penetrate to the finest-grained (plot-scale diversity component, at least not on acidic soils. Our findings are consistent with the contrasting regional Quaternary histories, but we also consider alternative explanatory models. Notably, ecological sorting and habitat connectivity may play a role in the unexpected limited or reversed region effect on plot α-diversity, and may also affect the larger-scale diversity

  17. Habitats as surrogates of taxonomic and functional fish assemblages in coral reef ecosystems: a critical analysis of factors driving effectiveness.

    Directory of Open Access Journals (Sweden)

    Simon Van Wynsberge

    Full Text Available Species check-lists are helpful to establish Marine Protected Areas (MPAs and protect local richness, endemicity, rarity, and biodiversity in general. However, such exhaustive taxonomic lists (i.e., true surrogate of biodiversity require extensive and expensive censuses, and the use of estimator surrogates (e.g., habitats is an appealing alternative. In truth, surrogate effectiveness appears from the literature highly variable both in marine and terrestrial ecosystems, making it difficult to provide practical recommendations for managers. Here, we evaluate how the biodiversity reference data set and its inherent bias can influence effectiveness. Specifically, we defined habitats by geomorphology, rugosity, and benthic cover and architecture criteria, and mapped them with satellite images for a New-Caledonian site. Fish taxonomic and functional lists were elaborated from Underwater Visual Censuses, stratified according to geomorphology and exposure. We then tested if MPA networks designed to maximize habitat richness, diversity and rarity could also effectively maximize fish richness, diversity, and rarity. Effectiveness appeared highly sensitive to the fish census design itself, in relation to the type of habitat map used and the scale of analysis. Spatial distribution of habitats (estimator surrogate's distribution, quantity and location of fish census stations (target surrogate's sampling, and random processes in the MPA design all affected effectiveness to the point that one small change in the data set could lead to opposite conclusions. We suggest that previous conclusions on surrogacy effectiveness, either positive or negative, marine or terrestrial, should be considered with caution, except in instances where very dense data sets were used without pseudo-replication. Although this does not rule out the validity of using surrogates of species lists for conservation planning, the critical joint examination of both target and estimator

  18. Animal water balance drives top-down effects in a riparian forest-implications for terrestrial trophic cascades.

    Science.gov (United States)

    McCluney, Kevin E; Sabo, John L

    2016-08-17

    Despite the clear importance of water balance to the evolution of terrestrial life, much remains unknown about the effects of animal water balance on food webs. Based on recent research suggesting animal water imbalance can increase trophic interaction strengths in cages, we hypothesized that water availability could drive top-down effects in open environments, influencing the occurrence of trophic cascades. We manipulated large spider abundance and water availability in 20 × 20 m open-air plots in a streamside forest in Arizona, USA, and measured changes in cricket and small spider abundance and leaf damage. As expected, large spiders reduced both cricket abundance and herbivory under ambient, dry conditions, but not where free water was added. When water was added (free or within moist leaves), cricket abundance was unaffected by large spiders, but spiders still altered herbivory, suggesting behavioural effects. Moreover, we found threshold-type increases in herbivory at moderately low soil moisture (between 5.5% and 7% by volume), suggesting the possibility that water balance may commonly influence top-down effects. Overall, our results point towards animal water balance as an important driver of direct and indirect species interactions and food web dynamics in terrestrial ecosystems. © 2016 The Author(s).

  19. Two-dimensional effects in the problem of tearing modes control by electron cyclotron current drive

    International Nuclear Information System (INIS)

    Comisso, L.; Lazzaro, E.

    2010-01-01

    The design of means to counteract robustly the classical and neoclassical tearing modes in a tokamak by localized injection of an external control current requires an ever growing understanding of the physical process, beyond the Rutherford-type zero-dimensional models. Here a set of extended magnetohydrodynamic nonlinear equations for four continuum fields is used to investigate the two-dimensional effects in the response of the reconnecting modes to specific inputs of the localized external current. New information is gained on the space- and time-dependent effects of the external action on the two-dimensional structure of magnetic islands, which is very important to formulate applicable control strategies.

  20. H1 antihistamines and driving.

    Science.gov (United States)

    Popescu, Florin Dan

    2008-01-01

    Driving performances depend on cognitive, psychomotor and perception functions. The CNS adverse effects of some H1 antihistamines can alter the patient ability to drive. Data from studies using standardized objective cognitive and psychomotor tests (Choice Reaction Time, Critical Flicker Fusion. Digital Symbol Substitution Test), functional brain imaging (Positron Emission Tomography, functional Magnetic Resonance Imaging), neurophysiological studies (Multiple Sleep Latency Test, auditory and visual evoked potentials), experimental simulated driving (driving simulators) and real driving studies (the Highway Driving Test, with the evaluation of the Standard Deviation Lateral Position, and the Car Following Test, with the measurement of the Brake Reaction Time) must be discussed in order to classify a H1 antihistamine as a true non-sedating one.

  1. Investigation of ion kinetic effects in direct-drive exploding-pusher implosions at the NIF

    Energy Technology Data Exchange (ETDEWEB)

    Rosenberg, M. J., E-mail: mrosenbe@mit.edu; Zylstra, A. B.; Séguin, F. H.; Rinderknecht, H. G.; Frenje, J. A.; Gatu Johnson, M.; Sio, H.; Waugh, C. J.; Sinenian, N.; Li, C. K.; Petrasso, R. D. [Plasma Science and Fusion Center, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139 (United States); McKenty, P. W.; Hohenberger, M.; Radha, P. B.; Delettrez, J. A.; Glebov, V. Yu.; Betti, R.; Goncharov, V. N.; Knauer, J. P.; Sangster, T. C. [Laboratory for Laser Energetics, University of Rochester, Rochester, New York 14623 (United States); and others

    2014-12-15

    Measurements of yield, ion temperature, areal density (ρR), shell convergence, and bang time have been obtained in shock-driven, D{sub 2} and D{sup 3}He gas-filled “exploding-pusher” inertial confinement fusion (ICF) implosions at the National Ignition Facility to assess the impact of ion kinetic effects. These measurements probed the shock convergence phase of ICF implosions, a critical stage in hot-spot ignition experiments. The data complement previous studies of kinetic effects in shock-driven implosions. Ion temperature and fuel ρR inferred from fusion-product spectroscopy are used to estimate the ion-ion mean free path in the gas. A trend of decreasing yields relative to the predictions of 2D DRACO hydrodynamics simulations with increasing Knudsen number (the ratio of ion-ion mean free path to minimum shell radius) suggests that ion kinetic effects are increasingly impacting the hot fuel region, in general agreement with previous results. The long mean free path conditions giving rise to ion kinetic effects in the gas are often prevalent during the shock phase of both exploding pushers and ablatively driven implosions, including ignition-relevant implosions.

  2. Two's a crowd? Crowding effect in a parasitic castrator drives differences in reproductive resource allocation in single vs double infections.

    Science.gov (United States)

    Fong, Caitlin R; Moron, Nancy A; Kuris, Armand M

    2017-04-01

    The 'crowding effect' is a result of competition by parasites within a host for finite resources. Typically, the severity of this effect increases with increasing numbers of parasites within a host and manifests in reduced body size and thus fitness. Evidence for the crowding effect is mixed - while some have found negative effects, others have found a positive effect of increased parasite load on parasite fitness. Parasites are consumers with diverse trophic strategies reflected in their life history traits. These distinctions are useful to predict the effects of crowding. We studied a parasitic castrator, a parasite that usurps host reproductive energy and renders the host sterile. Parasitic castrators typically occur as single infections within hosts. With multiple parasitic castrators, we expect strong competition and evidence of crowding. We directly assess the effect of crowding on reproductive success in a barnacle population infected by a unique parasitic castrator, Hemioniscus balani, an isopod parasite that infects and blocks reproduction of barnacles. We find (1) strong evidence of crowding in double infections, (2) increased frequency of double infections in larger barnacle hosts with more resources and (3) perfect compensation in egg production, supporting strong space limitation. Our results document that the effects of crowding are particularly severe for this parasitic castrator, and may be applicable to other castrators that are also resource or space limited.

  3. Effects of Pay-As-You-Drive vehicle insurance on young drivers' speed choice : Results of a Dutch field experiment

    NARCIS (Netherlands)

    Bolderdijk, J.W.; Knockaert, J.; Steg, L.; Verhoef, E.T.

    Speeding is an important cause for young drivers' involvement in traffic accidents. A reduction in driving speeds of this group could result in fewer accidents. One way of reducing driving speed is offering explicit financial incentives. In collaboration with five Dutch car insurance companies, we

  4. Resistive effects on helicity-wave current drive generated by Alfven waves in tokamak plasmas

    International Nuclear Information System (INIS)

    Bruma, C.; Cuperman, S.; Komoshvili, K.

    1997-01-01

    This work is concerned with the investigation of non-ideal (resistive) MHD effects on the excitation of Alfven waves by externally launched fast-mode waves, in simulated tokamak plasmas; both continuum range, CR ({ω Alf (r)} min Alf (r)} max ) and discrete range, DR, where global Alfven eigenmodes, GAEs (ω Alf (r)} min ) exist, are considered. (Here, ω Alf (r) ≡ ω Alf [n(r), B 0 (r)] is an eigenfrequency of the shear Alfven wave). For this, a cylindrical current carrying plasma surrounded by a helical sheet-current antenna and situated inside a perfectly conducting shell is used. Toroidicity effects are simulated by adopting for the axial equilibrium magnetic field component a suitable radial profile; shear and finite relative poloidal magnetic field are properly accounted for. A dielectric tensor appropriate to the physical conditions considered in this paper is derived and presented. (author)

  5. Effects of Water Diversion from Yangtze River to Lake Taihu on the Phytoplankton Habitat of the Wangyu River Channel

    Directory of Open Access Journals (Sweden)

    Jiangyu Dai

    2018-06-01

    Full Text Available To reveal the effects of water diversion from the Yangtze River to Lake Taihu on the phytoplankton habitat of the main water transfer channel of the Wangyu River, we investigated the water’s physicochemical parameters and phytoplankton communities during the water diversion and non-diversion periods over the winters between 2014–2016, respectively. During the water diversion periods in the winter of 2014 and 2015, the nutrients and organic pollutant contents of the Wangyu River channel were significantly lower than those during the non-diversion period in 2016. Moreover, the phytoplankton diversities and relative proportions of Bacillariophyta during the diversion periods evidently increased during the water diversion periods in winter. The increase in the water turbidity content, the decrease in the contents of the permanganate index, and the total phosphorus explained only 21.4% of the variations in the phytoplankton communities between the diversion and non-diversion periods in winter, which revealed significant contributions of the allochthonous species from the Yangtze River and tributaries of the Wangyu River to phytoplankton communities in the Wangyu River. The increasing gradient in the contents of nutrients and organic pollutants from the Yangtze River to Lake Taihu indicated the potential allochthonous pollutant inputs along with the Wangyu River. Further controlling the pollutants from the tributaries of the Wangyu River is critical in order to improve the phytoplankton habitats in river channels and Lake Taihu.

  6. Targeting Gene-Viro-Therapy with AFP driving Apoptin gene shows potent antitumor effect in hepatocarcinoma

    Directory of Open Access Journals (Sweden)

    Zhang Kang-Jian

    2012-02-01

    Full Text Available Abstract Background Gene therapy and viral therapy are used for cancer therapy for many years, but the results are less than satisfactory. Our aim was to construct a new recombinant adenovirus which is more efficient to kill hepatocarcinoma cells but more safe to normal cells. Methods By using the Cancer Targeting Gene-Viro-Therapy strategy, Apoptin, a promising cancer therapeutic gene was inserted into the double-regulated oncolytic adenovirus AD55 in which E1A gene was driven by alpha fetoprotein promoter along with a 55 kDa deletion in E1B gene to form AD55-Apoptin. The anti-tumor effects and safety were examined by western blotting, virus yield assay, real time polymerase chain reaction, 3-(4,5-dimethylthiazol-2-yl-2, 5-diphenyltetrazolium bromide assay, Hoechst33342 staining, Fluorescence-activated cell sorting, xenograft tumor model, Immunohistochemical assay, liver function analysis and Terminal deoxynucleotidyl transferase mediated dUTP Nick End Labeling assay. Results The recombinant virus AD55-Apoptin has more significant antitumor effect for hepatocelluar carcinoma cell lines (in vitro than that of AD55 and even ONYX-015 but no or little impair on normal cell lines. Furthermore, it also shows an obvious in vivo antitumor effect on the Huh-7 liver carcinoma xenograft in nude mice with bigger beginning tumor volume till about 425 mm3 but has no any damage on the function of liver. The induction of apoptosis is involved in AD55-Apoptin induced antitumor effects. Conclusion The AD55-Apoptin can be a potential anti-hepatoma agent with remarkable antitumor efficacy as well as higher safety in cancer targeting gene-viro-therapy system.

  7. The importance of moral emotions for effective collaboration in culturally diverse healthcare teams.

    Science.gov (United States)

    Cook, Catherine; Brunton, Margaret

    2018-04-01

    Moral emotions shape the effectiveness of culturally diverse teams. However, these emotions, which are integral to determining ethically responsive patient care and team relationships, typically go unrecognised. The contribution of emotions to moral deliberation is subjugated within the technorational environment of healthcare decision-making. Contemporary healthcare organisations rely on a multicultural workforce charged with the ethical care of vulnerable people. Limited extant literature examines the role of moral emotions in ethical decision-making among culturally diverse healthcare teams. Moral emotions are evident in ethnocentric moral perspectives that construct some colleagues' practices as 'other'. This article examines how moral emotions are evoked when cultural dissonance influences nurses' moral perceptions. We use a qualitative investigation of teamwork within culturally diverse healthcare organisations. We use Haidt's () account of moral emotions to examine practice-based accounts of 36 internationally educated and 17 New Zealand educated nurses practising in New Zealand. The study provides evidence that moral emotions are frequently elicited by communication and care practices considered 'foreign'. The main implication is that although safe practice in healthcare organisations is reliant on highly functioning teams, collaboration is challenged by interprofessional power relations of contested culturally shaped values. We address practice-based strategies that enable engagement with moral emotions to enhance effective teamwork. © 2017 John Wiley & Sons Ltd.

  8. Effects of Predation by Protists on Prokaryotic Community Function, Structure, and Diversity in Anaerobic Granular Sludge

    Science.gov (United States)

    Hirakata, Yuga; Oshiki, Mamoru; Kuroda, Kyohei; Hatamoto, Masashi; Kubota, Kengo; Yamaguchi, Takashi; Harada, Hideki; Araki, Nobuo

    2016-01-01

    Predation by protists is top-down pressure that regulates prokaryotic abundance, community function, structure, and diversity in natural and artificial ecosystems. Although the effects of predation by protists have been studied in aerobic ecosystems, they are poorly understood in anoxic environments. We herein studied the influence of predation by Metopus and Caenomorpha ciliates—ciliates frequently found in anoxic ecosystems—on prokaryotic community function, structure, and diversity. Metopus and Caenomorpha ciliates were cocultivated with prokaryotic assemblages (i.e., anaerobic granular sludge) in an up-flow anaerobic sludge blanket (UASB) reactor for 171 d. Predation by these ciliates increased the methanogenic activities of granular sludge, which constituted 155% of those found in a UASB reactor without the ciliates (i.e., control reactor). Sequencing of 16S rRNA gene amplicons using Illumina MiSeq revealed that the prokaryotic community in the UASB reactor with the ciliates was more diverse than that in the control reactor; 2,885–3,190 and 2,387–2,426 operational taxonomic units (>97% sequence similarities), respectively. The effects of predation by protists in anaerobic engineered systems have mostly been overlooked, and our results show that the influence of predation by protists needs to be examined and considered in the future for a better understanding of prokaryotic community structure and function. PMID:27431197

  9. Cutaneous tube ureterostomy: a fast and effective method of urinary diversion in emergency situations

    Directory of Open Access Journals (Sweden)

    Abdin T

    2015-06-01

    Full Text Available Tamer Abdin,1 Gideon Zamir,2 Alon Pikarsky,2 Ran Katz,1 Ezekiel H Landau,1 Ofer N Gofrit1 1Department of Urology, 2Department of General Surgery, Hadassah Hebrew University Hospital, Jerusalem, Israel Aim: To report on a simple and rapid method of urinary diversion. This method was applied successfully in different clinical scenarios when primary reconstruction of the ureters was not possible. Materials and methods: The disconnected ureter is catheterized by a feeding tube. The tube is secured with sutures and brought out to the lateral abdominal wall as cutaneous tube ureterostomy (CTU. Results: This method was applied in three different clinical scenarios: a 40-year-old man who sustained multiple high-velocity gunshots to the pelvis with combined rectal and bladder trigone injuries and massive bleeding from a comminuted pubic fracture. Damage control included colostomy and bilateral CTUs. A 26-year-old woman had transection of the right lower ureter during abdominal hysterectomy. Diagnosis was delayed for 3 weeks when the patient developed sepsis. The right kidney was diverted with a CTU. A 37-year-old male suffered from bladder perforation and hemorrhagic shock. Emergency cystectomy was done and urinary diversion was accomplished with bilateral CTUs. In all cases, effective drainage of the urinary system was achieved with normalization of kidney function. Conclusion: When local or systemic conditions preclude definitive repair and damage control surgery is needed, CTU provides fast and effective urinary diversion. Keywords: Ureter, trauma, tube cutenuous ureterostomy 

  10. What makes age diverse teams effective? Results from a six-year research program.

    Science.gov (United States)

    Wegge, J; Jungmann, F; Liebermann, S; Shemla, M; Ries, B C; Diestel, S; Schmidt, K-H

    2012-01-01

    Based on a new model of productivity in age diverse tams, findings from a six-year research program are reported in which data from more than 745 natural teams with 8,848 employees in three different fields (car production, administrative work, financial services) were collected. Moreover, central assumptions of this model were tested with a representative survey of the German workforce (N = 2,000). Results support both significant advantages and disadvantages for age-mixed teams. Based on the findings, the following preconditions for the effectiveness of age diverse teams are identified: high task complexity, low salience and high appreciation of age diversity, a positive team climate, low age-discrimination, ergonomic design of work places, and the use of age differentiated leadership. Based on these insights, we developed a new training for supervisors, which addresses the aforementioned aspects and seeks to improve team performance and health of team members. It was found that the training reduces age stereotypes, team conflicts and enhances innovation. Thus, we can conclude that effective interventions for a successful integration of elderly employees in work groups are available and that combinations of measures that address ergonomic design issues, team composition and leadership are to be strongly recommended for practice.

  11. Effects of different soil management practices on soil properties and microbial diversity

    Science.gov (United States)

    Gajda, Anna M.; Czyż, Ewa A.; Dexter, Anthony R.; Furtak, Karolina M.; Grządziel, Jarosław; Stanek-Tarkowska, Jadwiga

    2018-01-01

    The effects of different tillage systems on the properties and microbial diversity of an agricultural soil was investigated. In doing so, soil physical, chemical and biological properties were analysed in 2013-2015, on a long-term field experiment on a loamy sand at the IUNG-PIB Experimental Station in Grabów, Poland. Winter wheat was grown under two tillage treatments: conventional tillage using a mouldboard plough and traditional soil tillage equipment, and reduced tillage based on soil crushing-loosening equipment and a rigid-tine cultivator. Chopped wheat straw was used as a mulch on both treatments. Reduced tillage resulted in increased water content throughout the whole soil profile, in comparison with conventional tillage. Under reduced tillage, the content of readily dispersible clay was also reduced, and, therefore, soil stability was increased in the toplayers, compared with conventional tillage. In addition, the beneficial effects of reduced tillage were reflected in higher soil microbial activity as measured with dehydrogenases and hydrolysis of fluorescein diacetate, compared with conventional tillage. Moreover, the polimerase chain reaction - denaturing gradient gel electrophoresis analysis showed that soil under reduced till-age had greater diversity of microbial communities, compared with conventionally-tilled soil. Finally, reduced tillage increased organic matter content, stability in water and microbial diversity in the top layer of the soil.

  12. Effects of Predation by Protists on Prokaryotic Community Function, Structure, and Diversity in Anaerobic Granular Sludge.

    Science.gov (United States)

    Hirakata, Yuga; Oshiki, Mamoru; Kuroda, Kyohei; Hatamoto, Masashi; Kubota, Kengo; Yamaguchi, Takashi; Harada, Hideki; Araki, Nobuo

    2016-09-29

    Predation by protists is top-down pressure that regulates prokaryotic abundance, community function, structure, and diversity in natural and artificial ecosystems. Although the effects of predation by protists have been studied in aerobic ecosystems, they are poorly understood in anoxic environments. We herein studied the influence of predation by Metopus and Caenomorpha ciliates-ciliates frequently found in anoxic ecosystems-on prokaryotic community function, structure, and diversity. Metopus and Caenomorpha ciliates were cocultivated with prokaryotic assemblages (i.e., anaerobic granular sludge) in an up-flow anaerobic sludge blanket (UASB) reactor for 171 d. Predation by these ciliates increased the methanogenic activities of granular sludge, which constituted 155% of those found in a UASB reactor without the ciliates (i.e., control reactor). Sequencing of 16S rRNA gene amplicons using Illumina MiSeq revealed that the prokaryotic community in the UASB reactor with the ciliates was more diverse than that in the control reactor; 2,885-3,190 and 2,387-2,426 operational taxonomic units (>97% sequence similarities), respectively. The effects of predation by protists in anaerobic engineered systems have mostly been overlooked, and our results show that the influence of predation by protists needs to be examined and considered in the future for a better understanding of prokaryotic community structure and function.

  13. Effects of forests, roads and mistletoe on bird diversity in monoculture rubber plantations.

    Science.gov (United States)

    Sreekar, Rachakonda; Huang, Guohualing; Yasuda, Mika; Quan, Rui-Chang; Goodale, Eben; Corlett, Richard T; Tomlinson, Kyle W

    2016-02-23

    Rising global demand for natural rubber is expanding monoculture rubber (Hevea brasilensis) at the expense of natural forests in the Old World tropics. Conversion of forests into rubber plantations has a devastating impact on biodiversity and we have yet to identify management strategies that can mitigate this. We determined the life-history traits that best predict bird species occurrence in rubber plantations in SW China and investigated the effects of surrounding forest cover and distance to roads on bird diversity. Mistletoes provide nectar and fruit resources in rubber so we examined mistletoe densities and the relationship with forest cover and rubber tree diameter. In rubber plantations, we recorded less than half of all bird species extant in the surrounding area. Birds with wider habitat breadths and low conservation value had a higher probability of occurrence. Species richness and diversity increased logarithmically with surrounding forest cover, but roads had little effect. Mistletoe density increased exponentially with rubber tree diameters, but was unrelated to forest cover. To maximize bird diversity in rubber-dominated landscapes it is therefore necessary to preserve as much forest as possible, construct roads through plantations and not forest, and retain some large rubber trees with mistletoes during crop rotations.

  14. Finite Atwood Number Effects on Deceleration-Phase Instability in Room-Temperature Direct-Drive Implosions

    Science.gov (United States)

    Miller, S.; Knauer, J. P.; Radha, P. B.; Goncharov, V. N.

    2017-10-01

    Performance degradation in direct-drive inertial confinement fusion implosions can be caused by several effects, one of which is Rayleigh-Taylor (RT) instability growth during the deceleration phase. In room-temperature plastic target implosions, this deceleration-phase RT growth is enhanced by the density discontinuity and finite Atwood numbers at the fuel-pusher interface. For the first time, an experimental campaign at the Omega Laser Facility systematically varied the ratio of deuterium-to-tritium (D-to-T) within the DT gas fill to change the Atwood number. The goal of the experiment was to understand the effects of Atwood number variation on observables like apparent ion temperature, yield, and variations in areal density and bulk fluid motion, which lead to broadening of neutron spectra along different lines of sight. Simulations by the hydrodynamic codes LILAC and DRACO were used to study growth rates for different D-to-T ratios and identify observable quantities effected by Atwood number variation. Results from simulations and the experiment are presented. This material is based upon work supported by the Department of Energy National Nuclear Security Administration under Award Number DE-NA0001944.

  15. Reverse bistable effect in ferroelectric liquid crystal devices with ultra-fast switching at low driving voltage.

    Science.gov (United States)

    Guo, Qi; Zhao, Xiaojin; Zhao, Huijie; Chigrinov, V G

    2015-05-15

    In this Letter, reverse bistable effect with deep-sub-millisecond switching time is first reported in ferroelectric liquid crystal (FLC) devices using a homogeneous photo-alignment technique. It is indicated by our experimental results that both the anchoring energy and the dielectric property of the FLC's alignment layer is critical for the existence of the reverse bistable effect. In addition, with the derived criteria of the reverse bistable effect, we quantitatively analyze the switching dynamics of the reverse bistable FLC and the transition condition between the traditional bistability and our presented reverse bistability. Moreover, the fabricated FLC device exhibits an ultra-fast switching of ∼160  μs and a high contrast ratio of 1000:1, both of which were measured at a low driving voltage of 11 V. The featured deep-sub-millisecond switching time is really advantageous for our presented reverse bistable FLC devices, which enables a significant quality improvement of the existing optical devices, as well as a wide range of new applications in photonics and display areas.

  16. Dimensions of driving anger and their relationships with aberrant driving.

    Science.gov (United States)

    Zhang, Tingru; Chan, Alan H S; Zhang, Wei

    2015-08-01

    The purpose of this study was to investigate the relationship between driving anger and aberrant driving behaviours. An internet-based questionnaire survey was administered to a sample of Chinese drivers, with driving anger measured by a 14-item short Driving Anger Scale (DAS) and the aberrant driving behaviours measured by a 23-item Driver Behaviour Questionnaire (DBQ). The results of Confirmatory Factor Analysis demonstrated that the three-factor model (hostile gesture, arrival-blocking and safety-blocking) of the DAS fitted the driving anger data well. The Exploratory Factor Analysis on DBQ data differentiated four types of aberrant driving, viz. emotional violation, error, deliberate violation and maintaining progress violation. For the anger-aberration relation, it was found that only "arrival-blocking" anger was a significant positive predictor for all four types of aberrant driving behaviours. The "safety-blocking" anger revealed a negative impact on deliberate violations, a finding different from previously established positive anger-aberration relation. These results suggest that drivers with different patterns of driving anger would show different behavioural tendencies and as a result intervention strategies may be differentially effective for drivers of different profiles. Copyright © 2015 Elsevier Ltd. All rights reserved.

  17. The effects of coastal development on sponge abundance, diversity, and community composition on Jamaican coral reefs.

    Science.gov (United States)

    Stubler, Amber D; Duckworth, Alan R; Peterson, Bradley J

    2015-07-15

    Over the past decade, development along the northern coast of Jamaica has accelerated, resulting in elevated levels of sedimentation on adjacent reefs. To understand the effects of this development on sponge community dynamics, we conducted surveys at three locations with varying degrees of adjacent coastal development to quantify species richness, abundance and diversity at two depths (8-10 m and 15-18 m). Sediment accumulation rate, total suspended solids and other water quality parameters were also quantified. The sponge community at the location with the least coastal development and anthropogenic influence was often significantly different from the other two locations, and exhibited higher sponge abundance, richness, and diversity. Sponge community composition and size distribution were statistically different among locations. This study provides correlative evidence that coastal development affects aspects of sponge community ecology, although the precise mechanisms are still unclear. Copyright © 2015 Elsevier Ltd. All rights reserved.

  18. The effects of road building on arbuscular mycorrhizal fungal diversity in Huangshan Scenic Area.

    Science.gov (United States)

    Yang, Anna; Tang, Dongmei; Jin, Xiulong; Lu, Lin; Li, Xiaohong; Liu, Kun

    2018-01-22

    Arbuscular mycorrhizal (AM) fungi are vital soil microbes that connect many individual plants into a large functional organism via a vast mycelial network under the ground. In this study, the changes of soil AM fungal community in response to road-building disturbance caused by tourism development in Huangshan (Yellow Mountain) Scenic Area are assessed. Road building have brought negative effects on AM fungal community, inducing lower diversity parameters, including species number, spore density and diversity indices. However, the dominant genus and species of AM fungi which play key roles in the AM fungal community composition are quite similar before and after road building. Moreover, there are no significant differences in species richness of AM fungi associated with plants, suggesting the tolerance of AM fungal community to the disturbance of road building.

  19. The Effect of Mutual Coupling on a High Altitude Platform Diversity System Using Compact Antenna Arrays

    Directory of Open Access Journals (Sweden)

    Tommy Hult

    2010-01-01

    Full Text Available We analyze the destructive effects of mutual coupling and spatial correlation between the separate antenna elements on a combined diversity system consisting of multiple HAPs (High-Altitude Platforms employing various compact MIMO (Multiple-Input Multiple-Output antenna array configurations, in order to enhance the mutual information in HAP communication links. In addition, we assess the influence of the separation angle between HAPs on system performance, and determine the optimal separation angles that maximize the total mutual information of the system for various compact MIMO antennas. Simulation results show that although the mutual information is degraded by mutual coupling and spatial correlation, the proposed HAP diversity system still provides better performance compared to a nondiversity system for all tested scenarios.

  20. Does taxonomic diversity in indicator groups influence their effectiveness in identifying priority areas for species conservation?

    DEFF Research Database (Denmark)

    Bladt, Jesper Stentoft; Larsen, Frank Wugt; Rahbek, Carsten

    2008-01-01

    The identification of priority areas for biodiversity conservation is a cornerstone of systematic conservation planning. However, biodiversity, or even the distribution of all species, cannot be directly quantified, due to the inherent complexity of natural systems. Species indicator groups may...... serve as important tools for the identification of priority areas for conservation. Yet, it is unclear which factors make certain indicator groups perform better than others. In this study, using data on the Danish distribution of 847 species of plants, vertebrates and insects, we assessed whether...... the taxonomic diversity in species indicator groups influence their effectiveness in the identification of priority areas for species conservation. We tested whether indicator groups comprising a higher taxonomic diversity (i.e. indicator groups consisting of species from many different taxonomic groups...