WorldWideScience

Sample records for driving ontogenetic succession

  1. 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

  2. The Secret Driving Force Behind Mongolia’s Successful Democracy

    Science.gov (United States)

    2016-03-01

    the nation’s democracy movement its earliest stages. Courtesy of the Democratic Union of Mongolia PRISM 6, no. 1 FROM THE FIELD | 141 The Secret Driving...assistance and trade. Our state budget PRISM 6, no. 1 FROM THE FIELD | 143 THE SECRET DRIVING FORCE BEHIND MONGOLIA’S SUCCESSFUL DEMOCRACY collapsed; we...O yungerel Tsedevdam ba (2006) PRISM 6, no. 1 FROM THE FIELD | 145 THE SECRET DRIVING FORCE BEHIND MONGOLIA’S SUCCESSFUL DEMOCRACY significantly as

  3. Stochastic ontogenetic growth model

    Science.gov (United States)

    West, B. J.; West, D.

    2012-02-01

    An ontogenetic growth model (OGM) for a thermodynamically closed system is generalized to satisfy both the first and second law of thermodynamics. The hypothesized stochastic ontogenetic growth model (SOGM) is shown to entail the interspecies allometry relation by explicitly averaging the basal metabolic rate and the total body mass over the steady-state probability density for the total body mass (TBM). This is the first derivation of the interspecies metabolic allometric relation from a dynamical model and the asymptotic steady-state distribution of the TBM is fit to data and shown to be inverse power law.

  4. Factors Driving Learner Success in Online Professional Development

    Directory of Open Access Journals (Sweden)

    Phu Vu

    2014-07-01

    Full Text Available This study examined factors that contributed to the success of online learners in an online professional development course. Research instruments included an online survey and learners’ activity logs in an online professional development course for 512 in-service teachers. The findings showed that there were several factors affecting online learners’ success in online professional development. In addition, there were also significant differences between successful and unsuccessful online learners in terms of course login frequency and learning activities viewed.

  5. Conditions for success of engineered underdominance gene drive systems.

    Science.gov (United States)

    Edgington, Matthew P; Alphey, Luke S

    2017-10-07

    Engineered underdominance is one of a number of different gene drive strategies that have been proposed for the genetic control of insect vectors of disease. Here we model a two-locus engineered underdominance based gene drive system that is based on the concept of mutually suppressing lethals. In such a system two genetic constructs are introduced, each possessing a lethal element and a suppressor of the lethal at the other locus. Specifically, we formulate and analyse a population genetics model of this system to assess when different combinations of release strategies (i.e. single or multiple releases of both sexes or males only) and genetic systems (i.e. bisex lethal or female-specific lethal elements and different strengths of suppressors) will give population replacement or fail to do so. We anticipate that results presented here will inform the future design of engineered underdominance gene drive systems as well as providing a point of reference regarding release strategies for those looking to test such a system. Our discussion is framed in the context of genetic control of insect vectors of disease. One of several serious threats in this context are Aedes aegypti mosquitoes as they are the primary vectors of dengue viruses. However, results are also applicable to Ae. aegypti as vectors of Zika, yellow fever and chikungunya viruses and also to the control of a number of other insect species and thereby of insect-vectored pathogens. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

  6. What drives continuous improvement project success in healthcare?

    Science.gov (United States)

    Stelson, Paul; Hille, Joshua; Eseonu, Chinweike; Doolen, Toni

    2017-02-13

    Purpose The purpose of this paper is to present findings from a study of factors that affect continuous improvement (CI) project success in hospitals. Design/methodology/approach Quantitative regression analysis was performed on Likert scale survey responses. Qualitative thematic analysis was performed on open-ended survey responses and written reports on CI projects. Findings The paper identifies managerial and employee factors that affect project success. These factors include managerial support, communication, and affective commitment. Affective commitment is the extent to which employees perceive the change as being needed or necessary. Practical implications The results highlight how managerial decisions, approaches to communication - including communication before, during and after CI projects affect project success. The results also show that success depends on the way employees perceive proposed changes. This suggests the need for a more individualized approach to CI, lean, and broader change initiatives. Originality/value This research is the first to fuse project success and sustainability theory to CI projects, beyond Kaizen events, in healthcare environments. The research is particularly important at a time when healthcare organizations are required to make rapid changes with limited resources as they work toward outcome-based assessment and reimbursement rules.

  7. Higher survival drives the success of nitrogen-fixing trees through succession in Costa Rican rainforests.

    Science.gov (United States)

    Menge, Duncan N L; Chazdon, Robin L

    2016-02-01

    Trees capable of symbiotic nitrogen (N) fixation ('N fixers') are abundant in many tropical forests. In temperate forests, it is well known that N fixers specialize in early-successional niches, but in tropical forests, successional trends of N-fixing species are poorly understood. We used a long-term census study (1997-2013) of regenerating lowland wet tropical forests in Costa Rica to document successional patterns of N fixers vs non-fixers, and used an individual-based model to determine the demographic drivers of these trends. N fixers increased in relative basal area during succession. In the youngest forests, N fixers grew 2.5 times faster, recruited at a similar rate and were 15 times less likely to die as non-fixers. As succession proceeded, the growth and survival disparities decreased, whereas N fixer recruitment decreased relative to non-fixers. According to our individual-based model, high survival was the dominant driver of the increase in basal area of N fixers. Our data suggest that N fixers are successful throughout secondary succession in tropical rainforests of north-east Costa Rica, and that attempts to understand this success should focus on tree survival. © 2015 The Authors. New Phytologist © 2015 New Phytologist Trust.

  8. [Ontogenetic conditions of unemployment].

    Science.gov (United States)

    Buchtová, Božena; Smajs, Josef; Kulhavý, Viktor; Okrajek, Petr; Kukla, Lubomír

    2014-01-01

    Previous unemployment studies mostly dealt with unemployments economic causes and consequences. Hidden causes of male unemployment, independent from socio-economic circumstances of a society, could consist, besides others, in natural biological factors - family experience during childhood. Theoretical background of our study included the concept of psychical deprivation, the concept of human ontogenesis developmental stages of E. Erikson and knowledge of biodromal psychology. Using data from the European Longitudinal Study of Parenthood and Childhood international project we compared groups of employed and unemployed men by means of a retrospective survey and we studied the following: 1. What differences there were in their childhood; 2. To what extent educational approaches transfer from parents to their children; 3. What influence has negative experience from childhood on the future assertion of men in the labour market. The survey set consisted of 3141 (88.7%) employed men and 399 (11.3%) unemployed men in 1991-1992. Basic research data were acquired by means of questionnaires. Relative risk was used to compare the groups of the employed and the unemployed. The employed men are more likely to be from complete families then the unemployed men. The unemployed men, in comparison to the employed men, 2.08 times more frequently spent their childhood in orphanages, children's villages or in foster families, 3.89 times more frequently attended special schools, 2.22 times more frequently lived away from home until the age of 18 and 2.51 times more frequently lived in detention centres or in diagnostic institutes until the age of 18 (p unemployed men were psychically and physically abused in their childhood. Consequences of negative experience from childhood decrease the chances of inclusion of young men into the labour market. Social roles of young men (future fathers) could be also distorted by such experience. Social integration and social success rate of the

  9. Shared vision and autonomous motivation vs. financial incentives driving success in corporate acquisitions

    Science.gov (United States)

    Clayton, Byron C.

    2015-01-01

    Successful corporate acquisitions require its managers to achieve substantial performance improvements in order to sufficiently cover acquisition premiums, the expected return of debt and equity investors, and the additional resources needed to capture synergies and accelerate growth. Acquirers understand that achieving the performance improvements necessary to cover these costs and create value for investors will most likely require a significant effort from mergers and acquisitions (M&A) management teams. This understanding drives the common and longstanding practice of offering hefty performance incentive packages to key managers, assuming that financial incentives will induce in-role and extra-role behaviors that drive organizational change and growth. The present study debunks the assumptions of this common M&A practice, providing quantitative evidence that shared vision and autonomous motivation are far more effective drivers of managerial performance than financial incentives. PMID:25610406

  10. Shared vision and autonomous motivation vs. financial incentives driving success in corporate acquisitions.

    Science.gov (United States)

    Clayton, Byron C

    2014-01-01

    Successful corporate acquisitions require its managers to achieve substantial performance improvements in order to sufficiently cover acquisition premiums, the expected return of debt and equity investors, and the additional resources needed to capture synergies and accelerate growth. Acquirers understand that achieving the performance improvements necessary to cover these costs and create value for investors will most likely require a significant effort from mergers and acquisitions (M&A) management teams. This understanding drives the common and longstanding practice of offering hefty performance incentive packages to key managers, assuming that financial incentives will induce in-role and extra-role behaviors that drive organizational change and growth. The present study debunks the assumptions of this common M&A practice, providing quantitative evidence that shared vision and autonomous motivation are far more effective drivers of managerial performance than financial incentives.

  11. Shared Vision and Autonomous Motivation versus Financial Incentives Driving Success in Corporate Acquisitions

    Directory of Open Access Journals (Sweden)

    Byron C Clayton

    2015-01-01

    Full Text Available Successful corporate acquisitions require its managers to achieve substantial performance improvements in order to sufficiently cover acquisition premiums, the expected return of debt and equity investors, and the additional resources needed to capture synergies and accelerate growth. Acquirers understand that achieving the performance improvements necessary to cover these costs and create value for investors will most likely require a significant effort from mergers and acquisitions (M&A management teams. This understanding drives the common and longstanding practice of offering hefty performance incentive packages to key managers, assuming that financial incentives will induce in-role and extra-role behaviors that drive organizational change and growth. The present study debunks the assumptions of this common M&A practice, providing quantitative evidence that shared vision and autonomous motivation are far more effective drivers of managerial performance than financial incentives.

  12. Climate matching drives spread rate but not establishment success in recent unintentional bird introductions.

    Science.gov (United States)

    Abellán, Pedro; Tella, José L; Carrete, Martina; Cardador, Laura; Anadón, José D

    2017-08-29

    Understanding factors driving successful invasions is one of the cornerstones of invasion biology. Bird invasions have been frequently used as study models, and the foundation of current knowledge largely relies on species purposefully introduced during the 19th and early 20th centuries in countries colonized by Europeans. However, the profile of exotic bird species has changed radically in the last decades, as birds are now mostly introduced into the invasion process through unplanned releases from the worldwide pet and avicultural trade. Here we assessed the role of the three main drivers of invasion success (i.e., event-, species-, and location-level factors) on the establishment and spatial spread of exotic birds using an unprecedented dataset recorded throughout the last 100 y in the Iberian Peninsula. Our multimodel inference phylogenetic approach showed that the barriers that need to be overcome by a species to successfully establish or spread are not the same. Whereas establishment is largely related to event-level factors, apparently stochastic features of the introduction (time since first introduction and propagule pressure) and to the origin of introduced species (wild-caught species show higher invasiveness than captive-bred ones), the spread across the invaded region seems to be determined by the extent to which climatic conditions in the new region resemble those of the species' native range. Overall, these results contrast with what we learned from successful deliberate introductions and highlight that different management interventions should apply at different invasion stages, the most efficient strategies being related to event-level factors.

  13. Earthworms drive succession of both plant and Collembola communities in post-mining sites

    Science.gov (United States)

    Mudrák, Ondřej; Uteseny, Karoline; Frouz, Jan

    2016-04-01

    Previous field observations indicated that earthworms promote late-successional plant species and reduce collembolan numbers at post-mining sites in the Sokolov coal mining district (Czech Republic). Here, we established a laboratory pot experiment to test the effect of earthworms (Aporrectodea caliginosa Savigny and Lumbricus rubellus Hoffm.) and litter of low, medium, and high quality (the grass Calamagrostis epigejos, the willow Salix caprea, and the alder Alnus glutinosa, respectively) on late successional plants (grasses Arrhenatherum elatius and Agrostis capillaris, legumes Lotus corniculatus and Trifolium medium, and non-leguminous dicots Centaurea jacea and Plantago lanceolata) in spoil substrate originating from Sokolov post-mining sites and naturally inhabited by abundant numbers of Collembola. The earthworms increased plant biomass, especially that of the large-seeded A. elatius, but reduced the number of plant individuals, mainly that of the small-seeded A. capillaris and both legumes. Litter quality affected plant biomass, which was highest with S. caprea litter, but did not change the number of plant individuals. Litter quality did not modify the effect of earthworms on plants; the effect of litter quality and earthworms was only additive. Species composition of Collembola community was altered by litter quality, but earthworms reduced the number of individuals, increased the number of species, and increased species evenness consistently across the litter qualities. Because the results of this experiment were consistent with the field observations, we conclude that earthworms help drive succession of both plant and Collembola communities on post-mining sites.

  14. The limitations of ontogenetic data in phylogenetic analyses

    NARCIS (Netherlands)

    Koenemann, Stefan; Schram, Frederick R.

    2002-01-01

    The analysis of consecutive ontogenetic stages, or events, introduces a new class of data to phylogenetic systematics that are distinctly different from traditional morphological characters and molecular sequence data. Ontogenetic event sequences are distinguished by varying degrees of both a

  15. Predicting Academic Success: General Intelligence, "Big Five" Personality Traits, and Work Drive

    Science.gov (United States)

    Ridgell, Susan D.; Lounsbury, John W.

    2004-01-01

    General intelligence, Big Five personality traits, and the construct Work Drive were studied in relation to two measures of collegiate academic performance: a single course grade received by undergraduate students in an introductory psychology course, and self-reported GPA. General intelligence and Work Drive were found to be significantly…

  16. Factors driving territory size and breeding success in a threatened migratory songbird, the Canada Warbler

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    D. T. Tyler Flockhart

    2016-12-01

    Full Text Available Successful conservation of migratory birds demands we understand how habitat factors on the breeding grounds influences breeding success. Multiple factors are known to directly influence breeding success in territorial songbirds. For example, greater food availability and fewer predators can have direct effects on breeding success. However, many of these same habitat factors can also result in higher conspecific density that may ultimately reduce breeding success through density dependence. In this case, there is a negative indirect effect of habitat on breeding success through its effects on conspecific density and territory size. Therefore, a key uncertainty facing land managers is whether important habitat attributes directly influence breeding success or indirectly influence breeding success through territory size. We used radio-telemetry, point-counts, vegetation sampling, predator observations, and insect sampling over two years to provide data on habitat selection of a steeply declining songbird species, the Canada Warbler (Cardellina canadensis. These data were then applied in a hierarchical path modeling framework and an AIC model selection approach to determine the habitat attributes that best predict breeding success. Canada Warblers had smaller territories in areas with high shrub cover, in the presence of red squirrels (Tamiasciurus hudsonicus, at shoreline sites relative to forest-interior sites and as conspecific density increased. Breeding success was lower for birds with smaller territories, which suggests competition for limited food resources, but there was no direct evidence that food availability influenced territory size or breeding success. The negative relationship between shrub cover and territory size in our study may arise because these specific habitat conditions are spatially heterogeneous, whereby individuals pack into patches of preferred breeding habitat scattered throughout the landscape, resulting in reduced

  17. The ontogenetic ritualization of bonobo gestures.

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    Halina, Marta; Rossano, Federico; Tomasello, Michael

    2013-07-01

    Great apes communicate with gestures in flexible ways. Based on several lines of evidence, Tomasello and colleagues have posited that many of these gestures are learned via ontogenetic ritualization-a process of mutual anticipation in which particular social behaviors come to function as intentional communicative signals. Recently, Byrne and colleagues have argued that all great ape gestures are basically innate. In the current study, for the first time, we attempted to observe the process of ontogenetic ritualization as it unfolds over time. We focused on one communicative function between bonobo mothers and infants: initiation of "carries" for joint travel. We observed 1,173 carries in ten mother-infant dyads. These were initiated by nine different gesture types, with mothers and infants using many different gestures in ways that reflected their different roles in the carry interaction. There was also a fair amount of variability among the different dyads, including one idiosyncratic gesture used by one infant. This gestural variation could not be attributed to sampling effects alone. These findings suggest that ontogenetic ritualization plays an important role in the origin of at least some great ape gestures.

  18. The ontogenetic osteohistology of Tenontosaurus tilletti.

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    Sarah Werning

    Full Text Available Tenontosaurus tilletti is an ornithopod dinosaur known from the Early Cretaceous (Aptian-Albian Cloverly and Antlers formations of the Western United States. It is represented by a large number of specimens spanning a number of ontogenetic stages, and these specimens have been collected across a wide geographic range (from central Montana to southern Oklahoma. Here I describe the long bone histology of T. tilletti and discuss histological variation at the individual, ontogenetic and geographic levels. The ontogenetic pattern of bone histology in T. tilletti is similar to that of other dinosaurs, reflecting extremely rapid growth early in life, and sustained rapid growth through sub-adult ontogeny. But unlike other iguanodontians, this dinosaur shows an extended multi-year period of slow growth as skeletal maturity approached. Evidence of termination of growth (e.g., an external fundamental system is observed in only the largest individuals, although other histological signals in only slightly smaller specimens suggest a substantial slowing of growth later in life. Histological differences in the amount of remodeling and the number of lines of arrested growth varied among elements within individuals, but bone histology was conservative across sampled individuals of the species, despite known paleoenvironmental differences between the Antlers and Cloverly formations. The bone histology of T. tilletti indicates a much slower growth trajectory than observed for other iguanodontians (e.g., hadrosaurids, suggesting that those taxa reached much larger sizes than Tenontosaurus in a shorter time.

  19. Earthworms drive succession of both plant and Collembola communities in post-mining sites

    Czech Academy of Sciences Publication Activity Database

    Mudrák, Ondřej; Uteseny, Karoline; Frouz, Jan

    2016-01-01

    Roč. 18, April (2016), EGU2016-8464 ISSN 1607-7962. [European Geosciences Union General Assembly 2016. 17.04.2016-22.04.2016, Vienna] Institutional support: RVO:60077344 ; RVO:67985939 Keywords : earthworms * succession * plant communities * Collembola communities * post-mining sites Subject RIV: DF - Soil Science

  20. Ontogenetic shifts of heart position in snakes.

    Science.gov (United States)

    Lillywhite, Harvey B; Lillywhite, Steven M

    2017-08-01

    Heart position relative to total body length (TL) varies among snakes, with anterior hearts in arboreal species and more centrally located hearts in aquatic or ground-dwelling species. Anterior hearts decrease the cardiac work associated with cranial blood flow and minimize drops in cranial pressure and flow during head-up climbing. Here, we investigate whether heart position shifts intraspecifically during ontogenetic increases in TL. Insular Florida cottonmouth snakes, Agkistrodon conanti, are entirely ground-dwelling and have a mean heart position that is 33.32% TL from the head. In contrast, arboreal rat snakes, Pantherophis obsoleta, of similar lengths have a mean heart position that is 17.35% TL from the head. In both species, relative heart position shifts craniad during ontogeny, with negative slopes = -.035 and -.021% TL/cm TL in Agkistrodon and Pantherophis, respectively. Using a large morphometric data set available for Agkistrodon (N = 192 individuals, 23-140 cm TL), we demonstrate there is an anterior ontogenetic shift of the heart position within the trunk (= 4.56% trunk length from base of head to cloacal vent), independent of head and tail allometry which are both negative. However, in longer snakes > 100 cm, the heart position reverses and shifts caudally in longer Agkistrodon but continues toward the head in longer individuals of Pantherophis. Examination of data sets for two independent lineages of fully marine snakes (Acrochordus granulatus and Hydrophis platurus), which do not naturally experience postural gravity stress, demonstrate both ontogenetic patterns for heart position that are seen in the terrestrial snakes. The anterior migration of the heart is greater in the terrestrial species, even if TL is standardized to that of the longer P. obsoleta, and compensates for about 5 mmHg gravitational pressure head if they are fully upright. © 2017 Wiley Periodicals, Inc.

  1. On the relationship between ontogenetic and static allometry.

    Science.gov (United States)

    Pélabon, Christophe; Bolstad, Geir H; Egset, Camilla K; Cheverud, James M; Pavlicev, Mihaela; Rosenqvist, Gunilla

    2013-02-01

    Ontogenetic and static allometries describe how a character changes in size when the size of the organism changes during ontogeny and among individuals measured at the same developmental stage, respectively. Understanding the relationship between these two types of allometry is crucial to understanding the evolution of allometry and, more generally, the evolution of shape. However, the effects of ontogenetic allometry on static allometry remain largely unexplored. Here, we first show analytically how individual variation in ontogenetic allometry and body size affect static allometry. Using two longitudinal data sets on ontogenetic and static allometry, we then estimate variances and covariances for the different parameters of the ontogenetic allometry defined in our model and assess their relative contribution to the static allometric slope. The mean ontogenetic allometry is the main parameter that determines the static allometric slope, while the covariance between the ontogenetic allometric slope and body size generates most of the discrepancies between ontogenetic and static allometry. These results suggest that the apparent evolutionary stasis of the static allometric slope is not generated by internal (developmental) constraints but more likely results from external constraints imposed by selection.

  2. Sharing economy: a drive to success - The case of GO-JEK in Jakarta, Indonesia

    OpenAIRE

    Coupez, Alice

    2017-01-01

    Over the past decade, sharing economy has grown into a worldwide phenomenon. It has now arrived at a mature state of development, characterized by an intense competition on some markets. This master thesis analyses the development of this international phenomenon and focuses on the unexpected success of the Indonesian start-up GO-JEK in Jakarta. In fact, since its launch in 2015, GO-JEK has expanded its range of services, beating its international competitors Uber and Grab, and has become the...

  3. Leadership models and behaviors for sales executives. What drives success and the best results?

    Directory of Open Access Journals (Sweden)

    Dünnweber Matthias

    2017-07-01

    Full Text Available The paper analyses the effectiveness of the best leadership models and behaviours that are used by sales executives. Although, the impact of the most common characteristics and behaviours used in sales have been researched very well, recent research has only very limited results on a comparison of the most successful leadership personality traits and behaviours depending on companies’ situation and the context. In this paper we analyse two different situations: dynamic environment and stable environment. The context in this paper refers to the area sales. The paper will provide an explanation of the most successful leadership style used in sales and the characteristics of it and why they are also very useful in a sales process. Additionally, we will analyse the effectiveness of these characteristics in the two different situations of a company and exclusively in the sales context. We argue that the characteristics can be defined as the most effective one in every situation and context. We will develop a theoretical overview that shows clearly the best leadership traits and behaviours for each of the two situations in sales that is based on a literature research. The theoretical frameworks will be adjusted and confirmed with three senior sales executives from three different industries. The results of this paper will provide sales executives useful and easy to understand information about the advantages and disadvantages of the different leadership traits and behaviours depending on the context in and situation.

  4. Extreme Postnatal Scaling in Bat Feeding Performance: A View of Ecomorphology from Ontogenetic and Macroevolutionary Perspectives.

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    Santana, Sharlene E; Miller, Kimberly E

    2016-09-01

    Ecomorphology studies focus on understanding how anatomical and behavioral diversity result in differences in performance, ecology, and fitness. In mammals, the determinate growth of the skeleton entails that bite performance should change throughout ontogeny until the feeding apparatus attains its adult size and morphology. Then, interspecific differences in adult phenotypes are expected to drive food resource partitioning and patterns of lineage diversification. However, Formal tests of these predictions are lacking for the majority of mammal groups, and thus our understanding of mammalian ecomorphology remains incomplete. By focusing on a fundamental measure of feeding performance, bite force, and capitalizing on the extraordinary morphological and dietary diversity of bats, we discuss how the intersection of ontogenetic and macroevolutionary changes in feeding performance may impact ecological diversity in these mammals. We integrate data on cranial morphology and bite force gathered through longitudinal studies of captive animals and comparative studies of free-ranging individuals. We demonstrate that ontogenetic trajectories and evolutionary changes in bite force are highly dependent on changes in body and head size, and that bats exhibit dramatic, allometric increases in bite force during ontogeny. Interspecific variation in bite force is highly dependent on differences in cranial morphology and function, highlighting selection for ecological specialization. While more research is needed to determine how ontogenetic changes in size and bite force specifically impact food resource use and fitness in bats, interspecific diversity in cranial morphology and bite performance seem to closely match functional differences in diet. Altogether, these results suggest direct ecomorphological relationships at ontogenetic and macroevolutionary scales in bats. © The Author 2016. Published by Oxford University Press on behalf of the Society for Integrative and Comparative

  5. Environmental variability drives shifts in the foraging behaviour and reproductive success of an inshore seabird.

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    Kowalczyk, Nicole D; Reina, Richard D; Preston, Tiana J; Chiaradia, André

    2015-08-01

    Marine animals forage in areas that aggregate prey to maximize their energy intake. However, these foraging 'hot spots' experience environmental variability, which can substantially alter prey availability. To survive and reproduce animals need to modify their foraging in response to these prey shifts. By monitoring their inter-annual foraging behaviours, we can understand which environmental variables affect their foraging efficiency, and can assess how they respond to environmental variability. Here, we monitored the foraging behaviour and isotopic niche of little penguins (Eudyptula minor), over 3 years (2008, 2011, and 2012) of climatic and prey variability within Port Phillip Bay, Australia. During drought (2008), penguins foraged in close proximity to the Yarra River outlet on a predominantly anchovy-based diet. In periods of heavy rainfall, when water depth in the largest tributary into the bay (Yarra River) was high, the total distance travelled, maximum distance travelled, distance to core-range, and size of core- and home-ranges of penguins increased significantly. This larger foraging range was associated with broad dietary diversity and high reproductive success. These results suggest the increased foraging range and dietary diversity of penguins were a means to maximize resource acquisition rather than a strategy to overcome local depletions in prey. Our results demonstrate the significance of the Yarra River in structuring predator-prey interactions in this enclosed bay, as well as the flexible foraging strategies of penguins in response to environmental variability. This plasticity is central to the survival of this small-ranging, resident seabird species.

  6. Pluck or Luck: Does Trait Variation or Chance Drive Variation in Lifetime Reproductive Success?

    Science.gov (United States)

    Snyder, Robin E; Ellner, Stephen P

    2018-04-01

    While there has been extensive interest in how intraspecific trait variation affects ecological processes, outcomes are highly variable even when individuals are identical: some are lucky, while others are not. Trait variation is therefore important only if it adds substantially to the variability produced by luck. We ask when trait variation has a substantial effect on variability in lifetime reproductive success (LRS), using two approaches: (1) we partition the variation in LRS into contributions from luck and trait variation and (2) we ask what can be inferred about an individual's traits and with what certainty, given their observed LRS. In theoretical stage- and size-structured models and two empirical case studies, we find that luck usually dominates the variance of LRS. Even when individuals differ substantially in ways that affect expected LRS, unless the effects of luck are substantially reduced (e.g., low variability in reproductive life span or annual fecundity), most variance in lifetime outcomes is due to luck, implying that departures from "null" models omitting trait variation will be hard to detect. Luck also obscures the relationship between realized LRS and individual traits. While trait variation may influence the fate of populations, luck often governs the lives of individuals.

  7. Chemical cues released by an alien invasive aquatic gastropod drive its invasion success.

    Science.gov (United States)

    Raw, Jacqueline L; Miranda, Nelson A F; Perissinotto, Renzo

    2013-01-01

    Chemical cues provide aquatic organisms with sensory information that guides behavioural responses and thus interactions among themselves, each other and the environment. Chemical cues are considered important for predator avoidance, foraging, larval settlement and broadcast spawning in aquatic environments. However, the significance of their role as drivers of direct interactions between heterospecifics has been largely overlooked. A video camera and a demarcated arena were used in situ to record behavioural responses of three native gastropod species, Assiminea cf. capensis, Melanoides tuberculata and Coriandria durbanensis, exposed to treatments representing chemical cues released by a non-native invasive gastropod, Tarebia granifera. The responses were measured quantitatively as displacement and orientation of movement at locations in St Lucia Estuary, within the iSimangaliso Wetland Park, a UNESCO World Heritage Site on the east coast of South Africa. All native gastropods exhibited a negative taxis response to chemical cues released by T. granifera, while T. granifera individuals responded randomly to conspecifics. Displacement was measured relative to the source of the extract, the number of steps taken were determined with path analysis and orientation was determined from the mean (±95% CIs) turning angles, with significant negative turning angles representing negative taxis. Responses to treatments corresponding to the environment and conspecifics were random and undirected, indicating kinesis. This study presents evidence for interactions driven by chemical cues between a non-native invasive gastropod and several gastropods native to South Africa. The results indicate that chemical cues can facilitate invasion success as the behavioural response of native gastropods is to move away allowing additional food and space resources to become available to T. granifera.

  8. Microbial Interactions With Dissolved Organic Matter Drive Carbon Dynamics and Community Succession

    Directory of Open Access Journals (Sweden)

    Xiaoqin Wu

    2018-06-01

    Full Text Available Knowledge of dynamic interactions between natural organic matter (NOM and microbial communities is critical not only to delineate the routes of NOM degradation/transformation and carbon (C fluxes, but also to understand microbial community evolution and succession in ecosystems. Yet, these processes in subsurface environments are usually studied independently, and a comprehensive view has been elusive thus far. In this study, we fed sediment-derived dissolved organic matter (DOM to groundwater microbes and continually analyzed microbial transformation of DOM over a 50-day incubation. To document fine-scale changes in DOM chemistry, we applied high-resolution Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS and soft X-ray absorption spectroscopy (sXAS. We also monitored the trajectory of microbial biomass, community structure and activity over this time period. Together, these analyses provided an unprecedented comprehensive view of interactions between sediment-derived DOM and indigenous subsurface groundwater microbes. Microbial decomposition of labile C in DOM was immediately evident from biomass increase and total organic carbon (TOC decrease. The change of microbial composition was closely related to DOM turnover: microbial community in early stages of incubation was influenced by relatively labile tannin- and protein-like compounds; while in later stages the community composition evolved to be most correlated with less labile lipid- and lignin-like compounds. These changes in microbial community structure and function, coupled with the contribution of microbial products to DOM pool affected the further transformation of DOM, culminating in stark changes to DOM composition over time. Our study demonstrates a distinct response of microbial communities to biotransformation of DOM, which improves our understanding of coupled interactions between sediment-derived DOM, microbial processes, and community structure in

  9. Chemical cues released by an alien invasive aquatic gastropod drive its invasion success.

    Directory of Open Access Journals (Sweden)

    Jacqueline L Raw

    Full Text Available BACKGROUND: Chemical cues provide aquatic organisms with sensory information that guides behavioural responses and thus interactions among themselves, each other and the environment. Chemical cues are considered important for predator avoidance, foraging, larval settlement and broadcast spawning in aquatic environments. However, the significance of their role as drivers of direct interactions between heterospecifics has been largely overlooked. METHODOLOGY/PRINCIPAL FINDINGS: A video camera and a demarcated arena were used in situ to record behavioural responses of three native gastropod species, Assiminea cf. capensis, Melanoides tuberculata and Coriandria durbanensis, exposed to treatments representing chemical cues released by a non-native invasive gastropod, Tarebia granifera. The responses were measured quantitatively as displacement and orientation of movement at locations in St Lucia Estuary, within the iSimangaliso Wetland Park, a UNESCO World Heritage Site on the east coast of South Africa. All native gastropods exhibited a negative taxis response to chemical cues released by T. granifera, while T. granifera individuals responded randomly to conspecifics. Displacement was measured relative to the source of the extract, the number of steps taken were determined with path analysis and orientation was determined from the mean (±95% CIs turning angles, with significant negative turning angles representing negative taxis. Responses to treatments corresponding to the environment and conspecifics were random and undirected, indicating kinesis. CONCLUSION/SIGNIFICANCE: This study presents evidence for interactions driven by chemical cues between a non-native invasive gastropod and several gastropods native to South Africa. The results indicate that chemical cues can facilitate invasion success as the behavioural response of native gastropods is to move away allowing additional food and space resources to become available to T. granifera.

  10. Cranial ontogenetic variation in early saurischians and the role of heterochrony in the diversification of predatory dinosaurs.

    Science.gov (United States)

    Foth, Christian; Hedrick, Brandon P; Ezcurra, Martin D

    2016-01-01

    Non-avian saurischian skulls underwent at least 165 million years of evolution and shapes varied from elongated skulls, such as in the theropod Coelophysis, to short and box-shaped skulls, such as in the sauropod Camarasaurus. A number of factors have long been considered to drive skull shape, including phylogeny, dietary preferences and functional constraints. However, heterochrony is increasingly being recognized as an important factor in dinosaur evolution. In order to quantitatively analyse the impact of heterochrony on saurischian skull shape, we analysed five ontogenetic trajectories using two-dimensional geometric morphometrics in a phylogenetic framework. This allowed for the comparative investigation of main ontogenetic shape changes and the evaluation of how heterochrony affected skull shape through both ontogenetic and phylogenetic trajectories. Using principal component analyses and multivariate regressions, it was possible to quantify different ontogenetic trajectories and evaluate them for evidence of heterochronic events allowing testing of previous hypotheses on cranial heterochrony in saurischians. We found that the skull shape of the hypothetical ancestor of Saurischia likely led to basal Sauropodomorpha through paedomorphosis, and to basal Theropoda mainly through peramorphosis. Paedomorphosis then led from Orionides to Avetheropoda, indicating that the paedomorphic trend found by previous authors in advanced coelurosaurs may extend back into the early evolution of Avetheropoda. Not only are changes in saurischian skull shape complex due to the large number of factors that affected it, but heterochrony itself is complex, with a number of possible reversals throughout non-avian saurischian evolution. In general, the sampling of complete ontogenetic trajectories including early juveniles is considerably lower than the sampling of single adult or subadult individuals, which is a major impediment to the study of heterochrony on non-avian dinosaurs

  11. Variability in connectivity patterns of fish with ontogenetic migrations: Modelling effects of abiotic and biotic factors

    Directory of Open Access Journals (Sweden)

    Susanne Eva Tanner

    2015-10-01

    Full Text Available Connectivity is a critical property of marine fish populations as it drives population replenishment, determines colonization patterns and the resilience of populations to harvest. Understanding connectivity patterns is particularly important in species that present ontogenetic migrations and segregated habitat use during their life history, such as marine species with estuarine nursery areas. Albeit challenging, fish movement can be estimated and quantified using different methodologies depending on the life history stages of interest (e.g. biophysical modelling, otolith chemistry, genetic markers. Relative contributions from estuarine nursery areas to the adult coastal populations were determined using otolith elemental composition and maximum likelihood estimation for four commercially important species (Dicentrarchus labrax, Plathichtys flesus, Solea senegalensis and Solea solea and showed high interannual variability. Here, the effects of abiotic and biotic factors on the observed variability in connectivity rates and extent between estuarine juvenile and coastal adult subpopulations are investigated using generalized linear models (GLM and generalized mixed models (GMM. Abiotic factors impacting both larval and juvenile life history stages are included in the models (e.g. wind force and direction, NAO, water temperature while biotic factors relative to the estuarine residency of juvenile fish are evaluated (e.g. juvenile density, food availability. Factors contributing most to the observed variability in connectivity rates are singled out and compared among species. General trends are identified and results area discussed in the general context of identifying potential management frameworks applicable to different life stages and which may prove useful for ontogenetically migrating species.

  12. Ontogenetic polychromatism in marsupial frogs (Anura: Hylidae Ontogenetic polychromatism in marsupial frogs (Anura: Hylidae

    Directory of Open Access Journals (Sweden)

    Duellman William E.

    1986-12-01

    Full Text Available Color polymorphism is common in many species of marsupial frogs.  Extreme cases of pattern polymorphism are documented in four species. In Amphignathodon guentheri, Castrotheca aureomaculata, G. qriswoldi, and G. helenae juveniles are known to have only one color morph, where as two or more patterns exist in adults. In these species, polymorphism apparently develops ontogenetically. El polimorfismo cromático es común a algunas especies de sapos marsupiales. Casos extremos del modelo de polimorfismo son evidentes en cuatro especies Amphignathodon guentheri, Gastrotheca aureomaculata, G. griswoldi, y G. helenae. En estas especies, se sabe que los juveniles tienen sólo un morfo de color; el polimorfismo, al parecer, se desarrolla ontogenéticamente.

  13. Testing the ontogenetic base for the transient model of inflorescence development.

    Science.gov (United States)

    Bull-Hereñu, Kester; Claßen-Bockhoff, Regine

    2013-11-01

    Current research in plant science has concentrated on revealing ontogenetic processes of key attributes in plant evolution. One recently discussed model is the 'transient model' successful in explaining some types of inflorescence architectures based on two main principles: the decline of the so called 'vegetativeness' (veg) factor and the transient nature of apical meristems in developing inflorescences. This study examines whether both principles find a concrete ontogenetic correlate in inflorescence development. To test the ontogenetic base of veg decline and the transient character of apical meristems the ontogeny of meristematic size in developing inflorescences was investigated under scanning electron microscopy. Early and late inflorescence meristems were measured and compared during inflorescence development in 13 eudicot species from 11 families. The initial size of the inflorescence meristem in closed inflorescences correlates with the number of nodes in the mature inflorescence. Conjunct compound inflorescences (panicles) show a constant decrease of meristematic size from early to late inflorescence meristems, while disjunct compound inflorescences present an enlargement by merging from early inflorescence meristems to late inflorescence meristems, implying a qualitative change of the apical meristems during ontogeny. Partial confirmation was found for the transient model for inflorescence architecture in the ontogeny: the initial size of the apical meristem in closed inflorescences is consistent with the postulated veg decline mechanism regulating the size of the inflorescence. However, the observed biphasic kinetics of the development of the apical meristem in compound racemes offers the primary explanation for their disjunct morphology, contrary to the putative exclusive transient mechanism in lateral axes as expected by the model.

  14. Ontogenetic variation and craniometric sexual dimorphism in the ...

    African Journals Online (AJOL)

    The degree of maxillary molar tooth-row eruption and wear were used to assign samples of the social giant mole-rat, Fukomys mechowii, from Zambia, into nine relative age classes in order to assess ontogenetic (age) variation and craniometric sexual dimorphism, with reference to body mass. Univariate and multivariate ...

  15. Sperm competition, but not major histocompatibility divergence, drives differential fertilization success between alternative reproductive tactics in Chinook salmon.

    Science.gov (United States)

    Lehnert, S J; Helou, L; Pitcher, T E; Heath, J W; Heath, D D

    2018-01-01

    Post-copulatory sexual selection processes, including sperm competition and cryptic female choice (CFC), can operate based on major histocompatibility (MH) genes. We investigated sperm competition between male alternative reproductive tactics [jack (sneaker) and hooknose (guard)] of Chinook salmon (Oncorhynchus tshawytscha). Using a full factorial design, we examined in vitro competitive fertilization success of paired jack and hooknose males at three time points after sperm activation (0, 15 and 60 s) to test for male competition, CFC and time effects on male fertilization success. We also examined egg-mediated CFC at two MH genes by examining both the relationship between competitive fertilization success and MH divergence as well as inheritance patterns of MH alleles in resulting offspring. We found that jacks sired more offspring than hooknose males at 0 s post-activation; however, jack fertilization success declined over time post-activation, suggesting a trade-off between sperm speed and longevity. Enhanced fertilization success of jacks (presumably via higher sperm quality) may serve to increase sneaker tactic competitiveness relative to dominant hooknose males. We also found evidence of egg-mediated CFC (i.e. female × male interaction) influencing competitive fertilization success; however, CFC was not acting on the MH genes as we found no relationship between fertilization success and MH II β 1 or MH I α 1 divergence and we found no deviations from Mendelian inheritance of MH alleles in the offspring. Our study provides insight into evolutionary mechanisms influencing variation in male mating success within alternative reproductive tactics, thus underscoring different strategies that males can adopt to attain success. © 2017 European Society For Evolutionary Biology. Journal of Evolutionary Biology © 2017 European Society For Evolutionary Biology.

  16. Cranial ontogenetic variation in early saurischians and the role of heterochrony in the diversification of predatory dinosaurs

    Directory of Open Access Journals (Sweden)

    Christian Foth

    2016-01-01

    Full Text Available Non-avian saurischian skulls underwent at least 165 million years of evolution and shapes varied from elongated skulls, such as in the theropod Coelophysis, to short and box-shaped skulls, such as in the sauropod Camarasaurus. A number of factors have long been considered to drive skull shape, including phylogeny, dietary preferences and functional constraints. However, heterochrony is increasingly being recognized as an important factor in dinosaur evolution. In order to quantitatively analyse the impact of heterochrony on saurischian skull shape, we analysed five ontogenetic trajectories using two-dimensional geometric morphometrics in a phylogenetic framework. This allowed for the comparative investigation of main ontogenetic shape changes and the evaluation of how heterochrony affected skull shape through both ontogenetic and phylogenetic trajectories. Using principal component analyses and multivariate regressions, it was possible to quantify different ontogenetic trajectories and evaluate them for evidence of heterochronic events allowing testing of previous hypotheses on cranial heterochrony in saurischians. We found that the skull shape of the hypothetical ancestor of Saurischia likely led to basal Sauropodomorpha through paedomorphosis, and to basal Theropoda mainly through peramorphosis. Paedomorphosis then led from Orionides to Avetheropoda, indicating that the paedomorphic trend found by previous authors in advanced coelurosaurs may extend back into the early evolution of Avetheropoda. Not only are changes in saurischian skull shape complex due to the large number of factors that affected it, but heterochrony itself is complex, with a number of possible reversals throughout non-avian saurischian evolution. In general, the sampling of complete ontogenetic trajectories including early juveniles is considerably lower than the sampling of single adult or subadult individuals, which is a major impediment to the study of heterochrony on

  17. The successful of finite element to invent particle cleaning system by air jet in hard disk drive

    Science.gov (United States)

    Jai-Ngam, Nualpun; Tangchaichit, Kaitfa

    2018-02-01

    Hard Disk Drive manufacturing has faced very challenging with the increasing demand of high capacity drives for Cloud-based storage. Particle adhesion has also become increasingly important in HDD to gain more reliability of storage capacity. The ability to clean on surfaces is more complicated in removing such particles without damaging the surface. This research is aim to improve the particle cleaning in HSA by using finite element to develop the air flow model then invent the prototype of air cleaning system to remove particle from surface. Surface cleaning by air pressure can be applied as alternative for the removal of solid particulate contaminants that is adhering on a solid surface. These technical and economic challenges have driven the process development from traditional way that chemical solvent cleaning. The focus of this study is to develop alternative way from scrub, ultrasonic, mega sonic on surface cleaning principles to serve as a foundation for the development of new processes to meet current state-of-the-art process requirements and minimize the waste from chemical cleaning for environment safety.

  18. Ontogenetic patterns in the dreams of women across the lifespan.

    Science.gov (United States)

    Dale, Allyson; Lortie-Lussier, Monique; De Koninck, Joseph

    2015-12-01

    The present study supports and extends previous research on the developmental differences in women's dreams across the lifespan. The participants included 75 Canadian women in each of 5 age groups from adolescence to old age including 12-17, 18-24, 25-39, 40-64, and 65-85, totaling 375 women. One dream per participant was scored by two independent judges using the method of content analysis. Trend analysis was used to determine the ontogenetic pattern of the dream content categories. Results demonstrated significant ontogenetic decreases (linear trends) for female and familiar characters, activities, aggression, and friendliness. These patterns of dream imagery reflect the waking developmental patterns as proposed by social theories and recognized features of aging as postulated by the continuity hypothesis. Limitations and suggestions for future research including the examining of developmental patterns in the dreams of males are discussed. Copyright © 2015 Elsevier Inc. All rights reserved.

  19. Use of the Theoretical Domains Framework to evaluate factors driving successful implementation of the Accelerated Chest pain Risk Evaluation (ACRE) project.

    Science.gov (United States)

    Skoien, Wade; Page, Katie; Parsonage, William; Ashover, Sarah; Milburn, Tanya; Cullen, Louise

    2016-10-12

    The translation of healthcare research into practice is typically challenging and limited in effectiveness. The Theoretical Domains Framework (TDF) identifies 12 domains of behaviour determinants which can be used to understand the principles of behavioural change, a key factor influencing implementation. The Accelerated Chest pain Risk Evaluation (ACRE) project has successfully translated research into practice, by implementing an intervention to improve the assessment of low to intermediate risk patients presenting to emergency departments (EDs) with chest pain. The aims of this paper are to describe use of the TDF to determine which factors successfully influenced implementation and to describe use of the TDF as a tool to evaluate implementation efforts and which domains are most relevant to successful implementation. A 30-item questionnaire targeting clinicians was developed using the TDF as a guide. Questions encompassed ten of the domains of the TDF: Knowledge; Skills; Social/professional role and identity; Beliefs about capabilities; Optimism; Beliefs about consequences; Intentions; Memory, attention and decision processes; Environmental context and resources; and Social influences. Sixty-three of 176 stakeholders (36 %) responded to the questionnaire. Responses for all scales showed that respondents were highly favourable to all aspects of the implementation. Scales with the highest mean responses were Intentions, Knowledge, and Optimism, suggesting that initial education and awareness strategies around the ACRE project were effective. Scales with the lowest mean responses were Environmental context and resources, and Social influences, perhaps highlighting that implementation planning could have benefitted from further consideration of the factors underlying these scales. The ACRE project was successful, and therefore, a perfect case study for understanding factors which drive implementation success. The overwhelmingly positive response suggests that it

  20. Healthy competition drives success in results-based aid: Lessons from the Salud Mesoamérica Initiative.

    Science.gov (United States)

    El Bcheraoui, Charbel; Palmisano, Erin B; Dansereau, Emily; Schaefer, Alexandra; Woldeab, Alexander; Moradi-Lakeh, Maziar; Salvatierra, Benito; Hernandez-Prado, Bernardo; Mokdad, Ali H

    2017-01-01

    The Salud Mesoamérica Initiative (SMI) is a three-operation strategy, and is a pioneer in the world of results-based aid (RBA) in terms of the success it has achieved in improving health system inputs following its initial operation. This success in meeting pre-defined targets is rare in the world of financial assistance for health. We investigated the influential aspects of SMI that could have contributed to its effectiveness in improving health systems, with the aim of providing international donors, bilateral organizations, philanthropies, and recipient countries with new perspectives that can help increase the effectiveness of future assistance for health, specifically in the arena of RBA. Qualitative methods based on the criteria of relevance and effectiveness proposed by the Development Assistance Committee of the Organization for Economic Co-operation and Development. Our methods included document review, key informant interviews, a focus group discussion, and a partnership analysis. A purposive sample of 113 key informants, comprising donors, representatives from the Inter-American Development Bank, ministries of health, technical assistance organizations, evaluation organizations, and health care providers. During May-October 2016, we interviewed regarding the relevance and effectiveness of SMI. Themes emerged relative to the topics we investigated, and covered the design and the drivers of success of the initiative. The success is due to 1) the initiative's regional approach, which pressured recipient countries to compete toward meeting targets, 2) a robust and flexible design that incorporated the richness of input from stakeholders at all levels, 3) the design-embedded evaluation component that created a culture of accountability among recipient countries, and 4) the reflective knowledge environment that created a culture of evidence-based decision-making. A regional approach involving all appropriate stakeholders, and based on knowledge sharing and

  1. Mediterranean coastal dune vegetation: Are disturbance and stress the key selective forces that drive the psammophilous succession?

    Science.gov (United States)

    Ciccarelli, Daniela

    2015-11-01

    Plant communities of coastal dunes are distributed along a characteristic sea-inland gradient. Generally, there is a shift from annual and short height species with small leaves in the initial successional stages to perennial tall shrubs with tough leaves in later phases. Assessing the community-weighted mean (CWM) trait values is used in plant ecology to describe ecosystem properties especially during succession. In particular, CSR (Competitive, Stress-tolerant, and Ruderal strategy) classification allows us to explore community functional shifts in terms of disturbance, stress and competition selective forces. The functional basis of the psammophilous succession was studied based on the following questions: (1) Can we circumscribe different functional types among plant species of Mediterranean coastal dunes? (2) How do CWM trait values vary along the environmental sea-inland gradient? (3) What is the relative importance of competition, stress and disturbance in the processes of plant community assembling? (4) Can we postulate that along primary successions there is generally a shift from ruderality to stress-tolerance? An explorative analysis of functional groups was performed by Non-Metric Multidimensional Scaling (NMDS) analysing nine morpho-functional traits measured for 45 taxa from 880 dune plots localised in Tuscany (central Italy, Europe). NMDS ordination showed a scattered distribution of psammophytes that could not be delimited in precise plant functional types. The first NMDS axis has been interpreted as a leaf economics axis because it was correlated to leaf area (LA) and leaf dry matter content (LDMC), while the second one was a plant size axis because of its correlation with canopy height. Along the sea-inland gradient, pioneer plant communities of upper beach were dominated by ruderals (with the lowest values of LDMC and specific leaf area - SLA), well-adapted to the harsh environmental conditions of coastal dunes. More distant from the sea, where

  2. Mechanisms Driving Galling Success in a Fragmented Landscape: Synergy of Habitat and Top-Down Factors along Temperate Forest Edges.

    Directory of Open Access Journals (Sweden)

    Nina-S Kelch

    Full Text Available Edge effects play key roles in the anthropogenic transformation of forested ecosystems and their biota, and are therefore a prime field of contemporary fragmentation research. We present the first empirical study to address edge effects on the population level of a widespread galling herbivore in a temperate deciduous forest. By analyzing edge effects on abundance and trophic interactions of beech gall midge (Mikiola fagi Htg., we found 30% higher gall abundance in the edge habitat as well as lower mortality rates due to decreased top-down control, especially by parasitoids. Two GLM models with similar explanatory power (58% identified habitat specific traits (such as canopy closure and altitude and parasitism as the best predictors of gall abundance. Further analyses revealed a crucial influence of light exposure (46% on top-down control by the parasitoid complex. Guided by a conceptual framework synthesizing the key factors driving gall density, we conclude that forest edge proliferation of M. fagi is due to a complex interplay of abiotic changes and trophic control mechanisms. Most prominently, it is caused by the microclimatic regime in forest edges, acting alone or in synergistic concert with top-down pressure by parasitoids. Contrary to the prevailing notion that specialists are edge-sensitive, this turns M. fagi into a winner species in fragmented temperate beech forests. In view of the increasing proportion of edge habitats and the documented benefits from edge microclimate, we call for investigations exploring the pest status of this galling insect and the modulators of its biological control.

  3. Resources or landmarks: which factors drive homing success in Tetragonula carbonaria foraging in natural and disturbed landscapes?

    Science.gov (United States)

    Leonhardt, Sara D; Kaluza, Benjamin F; Wallace, Helen; Heard, Tim A

    2016-10-01

    To date, no study has investigated how landscape structural (visual) alterations affect navigation and thus homing success in stingless bees. We addressed this question in the Australian stingless bee Tetragonula carbonaria by performing marking, release and re-capture experiments in landscapes differing in habitat homogeneity (i.e., the proportion of elongated ground features typically considered prominent visual landmarks). We investigated how landscape affected the proportion of bees and nectar foragers returning to their hives as well as the earliest time bees and foragers returned. Undisturbed landscapes with few landmarks (that are conspicuous to the human eye) and large proportions of vegetation cover (natural forests) were classified visually/structurally homogeneous, and disturbed landscapes with many landmarks and fragmented or no extensive vegetation cover (gardens and plantations) visually/structurally heterogeneous. We found that proportions of successfully returning nectar foragers and earliest times first bees and foragers returned did not differ between landscapes. However, most bees returned in the visually/structurally most (forest) and least (garden) homogeneous landscape, suggesting that they use other than elongated ground features for navigation and that return speed is primarily driven by resource availability in a landscape.

  4. Nitrogen-controlled intra- and interspecific competition between Populus purdomii and Salix rehderiana drive primary succession in the Gongga Mountain glacier retreat area.

    Science.gov (United States)

    Song, Mengya; Yu, Lei; Jiang, Yonglei; Lei, Yanbao; Korpelainen, Helena; Niinemets, Ülo; Li, Chunyang

    2017-06-01

    In this study, intra- and interspecific competition were investigated in early successional Salix rehderiana Schneider and later-appearing Populus purdomii Rehder under non-fertilized (control) and nitrogen (N)-fertilized conditions in the Hailuogou glacier retreat area. Our aim was to discover whether N is a key factor in plant-plant competition and whether N drives the primary succession process in a glacier retreat area. We analyzed differences in responses to intra- and interspecific competition and N fertilization between P. purdomii and S. rehderiana, including parameters such as biomass accumulation, nutrient absorption, non-structural carbohydrates, photosynthetic capacity, hydrolysable amino acids and leaf ultrastructure. In the control treatments, S. rehderiana individuals subjected to interspecific competition benefited from the presence of P. purdomii plants, as indicated by higher levels of biomass accumulation, photosynthetic capacity, N absorption, amino acid contents and photosynthetic N-use efficiency. However, in the N-fertilized treatments, P. purdomii individuals exposed to interspecific competition benefited from the presence of S. rehderiana plants, as shown by a higher growth rate, enhanced carbon gain capacity, greater amino acid contents, and elevated water-use efficiency, whereas the growth of S. rehderiana was significantly reduced. Our results demonstrate that N plays a pivotal role in determining the asymmetric competition pattern among Salicaceae species during primary succession. We argue that the interactive effects of plant-plant competition and N availability are key mechanisms that drive primary succession in the Gongga Mountain glacier retreat area. © The Author 2017. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  5. Uniformity of spherical shock wave dynamically stabilized by two successive laser profiles in direct-drive inertial confinement fusion implosions

    Energy Technology Data Exchange (ETDEWEB)

    Temporal, M., E-mail: mauro.temporal@hotmail.com [Centre de Mathématiques et de Leurs Applications, ENS Cachan and CNRS, 61 Av. du President Wilson, F-94235 Cachan Cedex (France); Canaud, B. [CEA, DIF, F-91297 Arpajon Cedex (France); Garbett, W. J. [AWE plc, Aldermaston, Reading, Berkshire RG7 4PR (United Kingdom); Ramis, R. [ETSI Aeronáutica y del Espacio, Universidad Politécnica de Madrid, 28040 Madrid (Spain)

    2015-10-15

    The implosion uniformity of a directly driven spherical inertial confinement fusion capsule is considered within the context of the Laser Mégajoule configuration. Two-dimensional (2D) hydrodynamic simulations have been performed assuming irradiation with two laser beam cones located at 49° and 131° with respect to the axis of symmetry. The laser energy deposition causes an inward shock wave whose surface is tracked in time, providing the time evolution of its non-uniformity. The illumination model has been used to optimize the laser intensity profiles used as input in the 2D hydro-calculations. It is found that a single stationary laser profile does not maintain a uniform shock front over time. To overcome this drawback, it is proposed to use two laser profiles acting successively in time, in order to dynamically stabilize the non-uniformity of the shock front.

  6. Does temperature-mediated reproductive success drive the direction of species displacement in two invasive species of leafminer fly?

    Directory of Open Access Journals (Sweden)

    Haihong Wang

    Full Text Available Liriomyza sativae and L. trifolii (Diptera: Agromyzidae are two highly invasive species of leafmining flies, which have become established as pests of horticultural crops throughout the world. In certain regions where both species have been introduced, L. sativae has displaced L. trifolii, whereas the opposite has occurred in other regions. These opposing outcomes suggest that neither species is an inherently superior competitor. The regions where these displacements have been observed (southern China, Japan and western USA are climatically different. We determined whether temperature differentially affects the reproductive success of these species and therefore if climatic differences could affect the outcome of interspecific interactions where these species are sympatric. The results of life table parameters indicate that both species can develop successfully at all tested temperatures (20, 25, 31, 33°C. L. sativae had consistently higher fecundities at all temperatures, but L. trifolii developed to reproductive age faster. Age-stage specific survival rates were higher for L. sativae at low temperatures, but these were higher for L. trifolii at higher temperatures. We then compared the net reproductive rates (R0 for both species in pure and mixed cultures maintained at the same four constant temperatures. Both species had significantly lower net reproductive rates in mixed species cultures compared with their respective pure species cultures, indicating that both species are subject to intense interspecific competition. Net reproductive rates were significantly greater for L. sativae than for L. trifolii in mixed species groups at the lower temperatures, whereas the opposite occurred at the higher temperature. Therefore, interactions between the species are temperature dependent and small differences could shift the competitive balance between the species. These temperature mediated effects may contribute to the current ongoing displacement

  7. Ontogenetic Shape Change in the Chicken Brain: Implications for Paleontology.

    Science.gov (United States)

    Kawabe, Soichiro; Matsuda, Seiji; Tsunekawa, Naoki; Endo, Hideki

    2015-01-01

    Paleontologists have investigated brain morphology of extinct birds with little information on post-hatching changes in avian brain morphology. Without the knowledge of ontogenesis, assessing brain morphology in fossil taxa could lead to misinterpretation of the phylogeny or neurosensory development of extinct species. Hence, it is imperative to determine how avian brain morphology changes during post-hatching growth. In this study, chicken brain shape was compared at various developmental stages using three-dimensional (3D) geometric morphometric analysis and the growth rate of brain regions was evaluated to explore post-hatching morphological changes. Microscopic MRI (μMRI) was used to acquire in vivo data from living and post-mortem chicken brains. The telencephalon rotates caudoventrally during growth. This change in shape leads to a relative caudodorsal rotation of the cerebellum and myelencephalon. In addition, all brain regions elongate rostrocaudally and this leads to a more slender brain shape. The growth rates of each brain region were constant and the slopes from the growth formula were parallel. The dominant pattern of ontogenetic shape change corresponded with interspecific shape changes due to increasing brain size. That is, the interspecific and ontogenetic changes in brain shape due to increased size have similar patterns. Although the shape of the brain and each brain region changed considerably, the volume ratio of each brain region did not change. This suggests that the brain can change its shape after completing functional differentiation of the brain regions. Moreover, these results show that consideration of ontogenetic changes in brain shape is necessary for an accurate assessment of brain morphology in paleontological studies.

  8. Ontogenetic Shape Change in the Chicken Brain: Implications for Paleontology.

    Directory of Open Access Journals (Sweden)

    Soichiro Kawabe

    Full Text Available Paleontologists have investigated brain morphology of extinct birds with little information on post-hatching changes in avian brain morphology. Without the knowledge of ontogenesis, assessing brain morphology in fossil taxa could lead to misinterpretation of the phylogeny or neurosensory development of extinct species. Hence, it is imperative to determine how avian brain morphology changes during post-hatching growth. In this study, chicken brain shape was compared at various developmental stages using three-dimensional (3D geometric morphometric analysis and the growth rate of brain regions was evaluated to explore post-hatching morphological changes. Microscopic MRI (μMRI was used to acquire in vivo data from living and post-mortem chicken brains. The telencephalon rotates caudoventrally during growth. This change in shape leads to a relative caudodorsal rotation of the cerebellum and myelencephalon. In addition, all brain regions elongate rostrocaudally and this leads to a more slender brain shape. The growth rates of each brain region were constant and the slopes from the growth formula were parallel. The dominant pattern of ontogenetic shape change corresponded with interspecific shape changes due to increasing brain size. That is, the interspecific and ontogenetic changes in brain shape due to increased size have similar patterns. Although the shape of the brain and each brain region changed considerably, the volume ratio of each brain region did not change. This suggests that the brain can change its shape after completing functional differentiation of the brain regions. Moreover, these results show that consideration of ontogenetic changes in brain shape is necessary for an accurate assessment of brain morphology in paleontological studies.

  9. Ontogenetic specialism in predators with multiple niche shifts prevents predator population recovery and establishment

    NARCIS (Netherlands)

    van Leeuwen, A.; Huss, M.; Gårdmark, A.; de Roos, A.M.

    2014-01-01

    The effects of ontogenetic niche shifts on community structure and dynamics are underexplored, despite the occurrence of such shifts in the majority of animal species. We studied the form of niche shifts in a predator that exhibits multiple ontogenetic niche shifts, and analyzed how this life

  10. Evolution of extreme ontogenetic allometric diversity and heterochrony in pythons, a clade of giant and dwarf snakes.

    Science.gov (United States)

    Esquerré, Damien; Sherratt, Emma; Keogh, J Scott

    2017-12-01

    Ontogenetic allometry, how species change with size through their lives, and heterochony, a decoupling between shape, size, and age, are major contributors to biological diversity. However, macroevolutionary allometric and heterochronic trends remain poorly understood because previous studies have focused on small groups of closely related species. Here, we focus on testing hypotheses about the evolution of allometry and how allometry and heterochrony drive morphological diversification at the level of an entire species-rich and diverse clade. Pythons are a useful system due to their remarkably diverse and well-adapted phenotypes and extreme size disparity. We collected detailed phenotype data on 40 of the 44 species of python from 1191 specimens. We used a suite of analyses to test for shifts in allometric trajectories that modify morphological diversity. Heterochrony is the main driver of initial divergence within python clades, and shifts in the slopes of allometric trajectories make exploration of novel phenotypes possible later in divergence history. We found that allometric coefficients are highly evolvable and there is an association between ontogenetic allometry and ecology, suggesting that allometry is both labile and adaptive rather than a constraint on possible phenotypes. © 2017 The Author(s). Evolution © 2017 The Society for the Study of Evolution.

  11. Vulvar field resection: novel approach to the surgical treatment of vulvar cancer based on ontogenetic anatomy.

    Science.gov (United States)

    Höckel, Michael; Schmidt, Katja; Bornmann, Karoline; Horn, Lars-Christian; Dornhöfer, Nadja

    2010-10-01

    Current local treatment of vulvar cancer is wide tumor excision and radical vulvectomy based on functional anatomy established from the adult and on the view of radial progressive tumor permeation. Standard surgery is associated with a considerable local failure rate and severe disturbance of the patients' body image. Vulvar field resection (VFR) is based on ontogenetic anatomy and on the concept of local tumor spread within permissive compartments. VFR combined with anatomical reconstruction (AR) is proposed as a new surgical approach to the treatment of vulvar cancer. A prospective trial was launched to test the compartment theory for vulvar cancer and to assess safety and effectiveness of the new therapy. In 54 consecutive patients 46 tumors were locally confined to the tissue compartment differentiated from the vulvar anlage. The 8 tumors having transgressed into adjacent tissue compartments of different embryonic origins exhibited signs of advanced malignant progression. 38 patients with vulvar cancer, stages T1-3 were treated with VFR and AR. The perioperative complication rate was low. At 19 (3-50) months follow-up no patient failed locally. 33 patients estimated their body image as undisturbed. Vulvar cancer permeates within ontogenetic tissue compartments and surgical treatment with VFR and AR appears to be safe and effective. Patients should benefit from the new approach as local tumor control is high and the preserved tissue can be successfully used for restoration of vulvar form and function. Confirmatory trials with more patients and longer follow-up are suggested. Copyright © 2010 Elsevier Inc. All rights reserved.

  12. A hypothesis-testing framework for studies investigating ontogenetic niche shifts using stable isotope ratios.

    Directory of Open Access Journals (Sweden)

    Caroline M Hammerschlag-Peyer

    Full Text Available Ontogenetic niche shifts occur across diverse taxonomic groups, and can have critical implications for population dynamics, community structure, and ecosystem function. In this study, we provide a hypothesis-testing framework combining univariate and multivariate analyses to examine ontogenetic niche shifts using stable isotope ratios. This framework is based on three distinct ontogenetic niche shift scenarios, i.e., (1 no niche shift, (2 niche expansion/reduction, and (3 discrete niche shift between size classes. We developed criteria for identifying each scenario, as based on three important resource use characteristics, i.e., niche width, niche position, and niche overlap. We provide an empirical example for each ontogenetic niche shift scenario, illustrating differences in resource use characteristics among different organisms. The present framework provides a foundation for future studies on ontogenetic niche shifts, and also can be applied to examine resource variability among other population sub-groupings (e.g., by sex or phenotype.

  13. Ontogenetic changes in responses to settlement cues by Anemonefish

    Science.gov (United States)

    Dixson, D. L.; Munday, P. L.; Pratchett, M.; Jones, G. P.

    2011-12-01

    Population connectivity for most marine species is dictated by dispersal during the pelagic larval stage. Although reef fish larvae are known to display behavioral adaptations that influence settlement site selection, little is known about the development of behavioral preferences throughout the larval phase. Whether larvae are attracted to the same sensory cues throughout their larval phase, or exhibit distinct ontogenetic shifts in sensory preference is unknown. Here, we demonstrate an ontogenetic shift in olfactory cue preferences for two species of anemonefish, a process that could aid in understanding both patterns of dispersal and settlement. Aquarium-bred naïve Amphiprion percula and A. melanopus larvae were tested for olfactory preference of relevant reef-associated chemical cues throughout the 11-day pelagic larval stage. Age posthatching had a significant effect on the preference for olfactory cues from host anemones and live corals for both species. Preferences of olfactory cues from tropical plants of A. percula, increased by approximately ninefold between hatching and settlement, with A. percula larvae showing a fivefold increase in preference for the olfactory cue produced by the grass species. Larval age had no effect on the olfactory preference for untreated seawater over the swamp-based tree Melaleuca nervosa, which was always avoided compared with blank seawater. These results indicate that reef fish larvae are capable of utilizing olfactory cues early in the larval stage and may be predisposed to disperse away from reefs, with innate olfactory preferences drawing newly hatched larvae into the pelagic environment. Toward the end of the larval phase, larvae become attracted to the olfactory cues of appropriate habitats, which may assist them in identification of and navigation toward suitable settlement sites.

  14. Ontogenetic niche shifts and evolutionary branching in size-structured populations

    NARCIS (Netherlands)

    Claessen, D.; Dieckmann, U.

    2002-01-01

    There are many examples of size-structured populations where individuals sequentially exploit several niches in the course of their life history. Efficient exploitation of such ontogenetic niches generally requires specific morphological adaptations. Here, we study the evolutionary implications of

  15. Comparative vs ontogenetic paradigms for tests of the intrinsic mutagenesis hypothesis of aging

    Energy Technology Data Exchange (ETDEWEB)

    Sacher, G.A.

    1979-01-01

    This paper examines certain aspects of the biology of longevity and aging that bear on the role of DNA in the ontogenetic aging process, and on the genetic basis for the differences of longevity among mammal species. (PCS)

  16. Beyond body size: muscle biochemistry and body shape explain ontogenetic variation of anti-predatory behaviour in the lizard Salvator merianae.

    Science.gov (United States)

    de Barros, Fábio Cury; de Carvalho, José Eduardo; Abe, Augusto Shinya; Kohlsdorf, Tiana

    2016-06-01

    Anti-predatory behaviour evolves under the strong action of natural selection because the success of individuals avoiding predation essentially defines their fitness. Choice of anti-predatory strategies is defined by prey characteristics as well as environmental temperature. An additional dimension often relegated in this multilevel equation is the ontogenetic component. In the tegu Salvator merianae, adults run away from predators at high temperatures but prefer fighting when it is cold, whereas juveniles exhibit the same flight strategy within a wide thermal range. Here, we integrate physiology and morphology to understand ontogenetic variation in the temperature-dependent shift of anti-predatory behaviour in these lizards. We compiled data for body shape and size, and quantified enzyme activity in hindlimb and head muscles, testing the hypothesis that morphophysiological models explain ontogenetic variation in behavioural associations. Our prediction is that juveniles exhibit body shape and muscle biochemistry that enhance flight strategies. We identified biochemical differences between muscles mainly in the LDH:CS ratio, whereby hindlimb muscles were more glycolytic than the jaw musculature. Juveniles, which often use evasive strategies to avoid predation, have more glycolytic hindlimb muscles and are much smaller when compared with adults 1-2 years old. Ontogenetic differences in body shape were identified but marginally contributed to behavioural variation between juvenile and adult tegus, and variation in anti-predatory behaviour in these lizards resides mainly in associations between body size and muscle biochemistry. Our results are discussed in the ecological context of predator avoidance by individuals differing in body size living at temperature-variable environments, where restrictions imposed by the cold could be compensated by specific phenotypes. © 2016. Published by The Company of Biologists Ltd.

  17. The adaptive significance of ontogenetic colour change in a tropical python

    OpenAIRE

    Wilson, David; Heinsohn, Robert; Endler, John A

    2006-01-01

    Ontogenetic colour change is typically associated with changes in size, vulnerability or habitat, but assessment of its functional significance requires quantification of the colour signals from the receivers' perspective. The tropical python, Morelia viridis, is an ideal species to establish the functional significance of ontogenetic colour change. Neonates hatch either yellow or red and both the morphs change to green with age. Here, we show that colour change from red or yellow to green pr...

  18. Ontogenetic trajectories of chimpanzee social play: similarities with humans.

    Directory of Open Access Journals (Sweden)

    Giada Cordoni

    Full Text Available Social play, a widespread phenomenon in mammals, is a multifunctional behavior, which can have many different roles according to species, sex, age, relationship quality between playmates, group membership, context, and habitat. Play joins and cuts across a variety of disciplines leading directly to inquiries relating to individual developmental changes and species adaptation, thus the importance of comparative studies appears evident. Here, we aim at proposing a possible ontogenetic pathway of chimpanzee play (Pan troglodytes and contrast our data with those of human play. Chimpanzee play shows a number of changes from infancy to juvenility. Particularly, solitary and social play follows different developmental trajectories. While solitary play peaks in infancy, social play does not show any quantitative variation between infancy and juvenility but shows a strong qualitative variation in complexity, asymmetry, and playmate choice. Like laughter in humans, the playful expressions in chimpanzees (at the different age phases seem to have a role in advertising cooperative dispositions and intentions thus increasing the likelihood of engaging in solid social relationships. In conclusion, in chimpanzees, as in humans, both play behavior and the signals that accompany play serve multiple functions according to the different age phases.

  19. Plasticity during Early Brain Development Is Determined by Ontogenetic Potential.

    Science.gov (United States)

    Krägeloh-Mann, Ingeborg; Lidzba, Karen; Pavlova, Marina A; Wilke, Marko; Staudt, Martin

    2017-04-01

    Two competing hypotheses address neuroplasticity during early brain development: the "Kennard principle" describes the compensatory capacities of the immature developing CNS as superior to those of the adult brain, whereas the "Hebb principle" argues that the young brain is especially sensitive to insults. We provide evidence that these principles are not mutually exclusive. Following early brain lesions that are unilateral, the brain can refer to homotopic areas of the healthy hemisphere. This potential for reorganization is unique to the young brain but available only when, during ontogenesis of brain development, these areas have been used for the functions addressed. With respect to motor function, ipsilateral motor tracts can be recruited, which are only available during early brain development. Language can be reorganized to the right after early left hemispheric lesions, as the representation of the language network is initially bilateral. However, even in these situations, compensatory capacities of the developing brain are found to have limitations, probably defined by early determinants. Thus, plasticity and adaptivity are seen only within ontogenetic potential; that is, axonal or cortical structures cannot be recruited beyond early developmental possibilities. The young brain is probably more sensitive and vulnerable to lesions when these are bilateral. This is shown here for bilateral periventricular white matter lesions that clearly have an impact on cortical architecture and function, thus probably interfering with early network building. Georg Thieme Verlag KG Stuttgart · New York.

  20. The making of a monster: postnatal ontogenetic changes in craniomandibular shape in the great sabercat Smilodon.

    Directory of Open Access Journals (Sweden)

    Per Christiansen

    Full Text Available Derived sabercats had craniomandibular morphologies that in many respects were highly different from those of extant felids, and this has often been interpreted functionally as adaptations for predation at extreme gape angles with hypertrophied upper canines. It is unknown how much of this was a result of intraspecific postnatal ontogeny, since juveniles of sabercats are rare and no quantitative study has been made of craniomandibular ontogeny. Postnatal ontogenetic craniomandibular shape changes in two morphologically derived sabercats, Smilodon fatalis and S. populator, were analysed using geometric morphometrics and compared to three species of extant pantherines, the jaguar, tiger, and Sunda clouded leopard. Ontogenetic shape changes in Smilodon usually involved the same areas of the cranium and mandible as in extant pantherines, and large-scale modularization was similar, suggesting that such may have been the case for all felids, since it followed the same trends previously observed in other mammals. However, in other respects Smilodon differed from extant pantherines. Their crania underwent much greater and more localised ontogenetic shape changes than did the mandibles, whereas crania and mandibles of extant pantherines underwent smaller, fewer and less localised shape changes. Ontogenetic shape changes in the two species of Smilodon are largely similar, but differences are also present, notably those which may be tied to the presence of larger upper canines in S. populator. Several of the specialized cranial characters differentiating adult Smilodon from extant felids in a functional context, which are usually regarded as evolutionary adaptations for achieving high gape angles, are ontogenetic, and in several instances ontogeny appears to recapitulate phylogeny to some extent. No such ontogenetic evolutionary adaptive changes were found in the extant pantherines. Evolution in morphologically derived sabercats involved greater cranial

  1. 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...

  2. Ontogenetic evidence for the Paleozoic ancestry of salamanders.

    Science.gov (United States)

    Schoch, Rainer R; Carroll, Robert L

    2003-01-01

    The phylogenetic positions of frogs, salamanders, and caecilians have been difficult to establish. Data matrices based primarily on Paleozoic taxa support a monophyletic origin of all Lissamphibia but have resulted in widely divergent hypotheses of the nature of their common ancestor. Analysis that concentrates on the character states of the stem taxa of the extant orders, in contrast, suggests a polyphyletic origin from divergent Paleozoic clades. Comparison of patterns of larval development in Paleozoic and modern amphibians provides a means to test previous phylogenies based primarily on adult characteristics. This proves to be highly informative in the case of the origin of salamanders. Putative ancestors of salamanders are recognized from the Permo-Carboniferous boundary of Germany on the basis of ontogenetic changes observed in fossil remains of larval growth series. The entire developmental sequence from hatching to metamorphosis is revealed in an assemblage of over 600 specimens from a single locality, all belonging to the genus Apateon. Apateon forms the most speciose genus of the neotenic temnospondyl family Branchiosauridae. The sequence of ossification of individual bones and the changing configuration of the skull closely parallel those observed in the development of primitive living salamanders. These fossils provide a model of how derived features of the salamander skull may have evolved in the context of feeding specializations that appeared in early larval stages of members of the Branchiosauridae. Larvae of Apateon share many unique derived characters with salamanders of the families Hynobiidae, Salamandridae, and Ambystomatidae, which have not been recognized in any other group of Paleozoic amphibians.

  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. [Diabetes mellitus in elderly: comorbid characteristics of patients with different ontogenetic forms of the disease].

    Science.gov (United States)

    Odin, V I; Belikova, T V; Shustov, S B; Pushkova, E S; Emanuél', V L

    2006-01-01

    Diabetes in elderly is the interdisciplinary problem of diabetology and gerontology. Unlike adults the specific feature of these patients is comorbidities. On the other hand well known is the influence both age and aging on clinical sings of diabetes. The aim of the study was to investigate prevalence and structure comorbid chronic diseases in elderly patients with different ontogenetic forms of diabetes mellitus type 2 (DM2). We examined 169 elderly women with clinical diagnosis "DM2" (mean age--69.8 yrs., mean BMI--29.5 kg/m2, mean HbA1c--7.03%). The stratification was made by ontogenetic stage of diabetes onset and there were five ontogenetic forms of DM2: menstrual (Ms), early-postmenopausal (EPM), late-postmenopausal (LPM), early-involutional (EI) and late-involutional (LI). Anthropometrical, biochemical and immunochemical assays (HbA1c) were made by standard methods. Gognitive index (CGI) and affective index (AFI) were calculated by SCAG scale as mentalmnestic and affective disturbances accordingly. Comorbid index (CI) was calculated as a sum of concomitant diseases. The most comorbid serious was the early-postmenopausal group (CI--6.04 +/- 0.5), mainly by hypertension (92%) coronary heart disease (80%) and osteoarthritis (80%). The lightest comorbid status was in the late-involutional group (CI--4.5 +/- 0.3), with the minimum of gastroenterological diseases (39.5%), kidney diseases (26.3%), thyroid disorders (23.7%) and exclusively the group had valid negative relationship between age and CI (r = -0.550, p = 0.000). As a whole in the elderly diabetic cohort the magnitude of CI correlated positively with BMI (r = +0.344, p = 0.000), frequency of family diabetes (r = +0.204, p = 0.009), AFI (r = +0.161, p = 0.040), menarche (r = +0.175, p = 0.025) and no significantly with CGI (p > 0.05). Thus early ontogenetic forms of DM2 had more comorbidities, especially those with onset DM2 during first 5 years after menopause. And on the contrary, the latest ontogenetic

  5. A Parent-Offspring Trade-Off Limits the Evolution of an Ontogenetic Niche Shift

    NARCIS (Netherlands)

    ten Brink, H.; de Roos, A.M.

    2017-01-01

    Many free-living animal species, including the majority of fish, insects, and amphibians, change their food and habitat during their life. Even though these ontogenetic changes in niche are common, it is not well understood which ecological conditions have favored the evolution of these shifts.

  6. The role of Ontogenetic Herbarium in Studying Intra-Population Biodiversity

    International Nuclear Information System (INIS)

    Osmanova, G. O.; Kozyreva, S. V.; Vedernikova, O. P.; Zhukova, L. A.

    2016-01-01

    Studying biodiversity of plants on the population level is impossible without describing ontogenesis of species. Creatinga unique Ontogenesis herbarium at Mari State University and official registration of its collections in the International catalogue World Herbaria are to solve this problem. Ontogenesis herbarium is a herbarium of plants at different levels of individual development. Ontogenetic states are distinguished by using the concept of ontogenesis discrete description with regard to morphological features-markers. Plants are referred to this or that ontogenetic state on the basis of the complex of qualitative features. The most significant of them are the following: relationship with the seed, presence of embryonic, juvenile or adult structures and seed or vegetative reproduction capability of individuals, correlation of the processes of new growth and die off, individual formation degree of the life form main features. Complete ontogenesis of perennial plants includes 12 ontogenetic states: seed, plantules, juvenile, immature, virginile (young vegetative), cryptogenerative, young (early generative), middle age (mature generative), old (later generative), subsenile, senile, dying plant. The collection of the Ontogenesis herbarium is a part of the Population-ontogenetic museum which is a scientific and educational establishment, it is presented in the form of museum exhibitions and consists of six departments: General, Theme-based, Ontogenesis first stages, Collection of fruits and seeds, Izoteka (Picture collection), Phototeka (Photo collection) and Library. (author)

  7. Shape shifting predicts ontogenetic changes in metabolic scaling in diverse aquatic invertebrates

    DEFF Research Database (Denmark)

    Glazier, Douglas S.; Hirst, Andrew G.; Atkinson, D.

    2016-01-01

    in metabolic scaling that deviate from 3/4-power scaling predicted by general models. Here, we show that in diverse aquatic invertebrates, ontogenetic shifts in the scaling of routine metabolic rate from near isometry (bR = scaling exponent approx. 1) to negative allometry (bR

  8. Radiogenetic effect of gamma irradiation under different ontogenetic states of sweet pepper

    Energy Technology Data Exchange (ETDEWEB)

    Auni, S; Daskalov, S Kh; Filev, K A [Bylgarska Akademiya na Naukite, Sofia. Institut po Genetika

    1978-01-01

    In view of the practical utilization of the experimental mutagenesis, a detailed study of the radiosensitivity and the genetic effect on treatment at different phases of the ontogenetic development in the capsicum plant was carried out. Seven phases of the ontogenetic development were subjected to acute gamma irradiation with different doses: mature binuclear pollen, male and female gametophytes, zygotes, 15-day embryo, 30-day embryo, dry and germinated seeds. The mutagenic effect was recorded on the basis of the germination, fertility, number of fruits, number of sterile plants, weight of the seeds from the fruits, and frequency and spectrum of chlorophyll and morphological mutations. In all cases the radiobiological effect is increasing linearly in dependence of the applied dose. The analysis of the LD/sub 50/, assessed for the different indices of radiation injuries, did not show significant differences in the radiosensitivity of the first five phases from the ontogenetic development. Dry seeds, however, are almost 10 times more radiosensitive. The germinated seeds occupy an intermediate position as regards the indicator of fertility only. The yield of both the chlorophyll and morphological mutations is increasing also linearly with the increasing of the dose at all phases of the ontogenetic development. The highest yield is observed at the phases of gametophytes and dry seeds and the smallest at the phase of germinated seeds. The phases of zygotes and embryo on the 15th day hold an intermediate position. In all investigated phases the amount of the morphological mutations is higher than that of the chlorophyll ones.

  9. The ontogenetic origins of skull shape disparity in the Triturus cristatus group.

    Science.gov (United States)

    Cvijanović, Milena; Ivanović, Ana; Kalezić, Miloš L; Zelditch, Miriam L

    2014-09-01

    Comparative studies of ontogenies of closely related species provide insights into the mechanisms responsible for morphological diversification. Using geometric morphometrics, we investigated the ontogenetic dynamics of postlarval skull shape and disparity in three closely related crested newt species. The skull shapes of juveniles just after metamorphosis (hereafter metamorphs) and adult individuals were sampled by landmark configurations that describe the shape of the dorsal and ventral side of the newt skull, and analyzed separately. The three species differ in skull size and shape in metamorphs and adults. The ontogenies of dorsal and ventral skull differ in the orientation but not lengths of the ontogenetic trajectories. The disparity of dorsal skull shape increases over ontogeny, but that of ventral skull shape does not. Thus, modifications of ontogenetic trajectories can, but need not, increase the disparity of shape. In species with biphasic life-cycles, when ontogenetic trajectories for one stage can be decoupled from those of another, increases and decreases in disparity are feasible, but our results show that they need not occur. © 2014 Wiley Periodicals, Inc.

  10. 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 ...

  11. 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. ...

  12. Heritability of hsp70 expression in the beetle Tenebrio molitor: Ontogenetic and environmental effects.

    Science.gov (United States)

    Lardies, Marco A; Arias, María Belén; Poupin, María Josefina; Bacigalupe, Leonardo D

    2014-08-01

    Ectotherms constitute the vast majority of terrestrial biodiversity and are especially likely to be vulnerable to climate warming because their basic physiological functions such as locomotion, growth, and reproduction are strongly influenced by environmental temperature. An integrated view about the effects of global warming will be reached not just establishing how the increase in mean temperature impacts the natural populations but also establishing the effects of the increase in temperature variance. One of the molecular responses that are activated in a cell under a temperature stress is the heat shock protein response (HSP). Some studies that have detected consistent differences among thermal treatments and ontogenetic stages in HSP70 expression have assumed that these differences had a genetic basis and consequently expression would be heritable. We tested for changes in quantitative genetic parameters of HSP70 expression in a half-sib design where individuals of the beetle Tenebrio molitor were maintained in constant and varying thermal environments. We estimated heritability of HSP70 expression using a linear mixed modelling approach in different ontogenetic stages. Expression levels of HSP70 were consistently higher in the variable environment and heritability estimates were low to moderate. The results imply that within each ontogenetic stage additive genetic variance was higher in the variable environment and in adults compared with constant environment and larvae stage, respectively. We found that almost all the genetic correlations across ontogenetic stages and environment were positive. These suggest that directional selection for higher levels of expression in one environment will result in higher expression levels of HSP70 on the other environment for the same ontogenetic stage. Copyright © 2014 Elsevier Ltd. All rights reserved.

  13. 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

  14. Oil collecting bees and Byrsonima cydoniifolia A. Juss. (Malpighiaceae interactions: the prevalence of long-distance cross pollination driving reproductive success

    Directory of Open Access Journals (Sweden)

    MORGANA S. SAZAN

    2014-03-01

    Full Text Available Oil-collecting bees are the natural pollinators of oil-flower plants, but little is known about the pollination process and the effectiveness of their pollination service to the reproductive success of their host plants. In species of Byrsonima the reproductive system have been described as auto-compatible or self-incompatible. We studied the reproductive system of Byrsonima cydoniifolia, the fructification by means of short, medium and long-distance cross pollinations, the morphology and floral biology and the pollination interactions with species of oil-collecting bees. By means of controlled pollinations we found self-incompatibility caused by abortion of most self-pollinated flowers and demonstrated that the prevailing cross pollination ensuring the reproductive success of B. cydoniifolia is the long-distance cross pollination and Centridini bees; Epicharis nigrita, particularly, are the pollinators promoting the gene flow between genetically distinct populations.

  15. Insights into Feast-Famine polyhydroxyalkanoate (PHA)-producer selection: Microbial community succession, relationships with system function and underlying driving forces.

    Science.gov (United States)

    Huang, Long; Chen, Zhiqiang; Wen, Qinxue; Zhao, Lizhi; Lee, Duu-Jong; Yang, Lian; Wang, Yao

    2017-12-18

    The Feast-Famine (FF) process has been frequently used to select polyhydroxyalkanoate (PHA)-accumulating mixed cultures (MCs), but there has been little insight into the ecophysiology of the microbial community during the selection process. In three FF systems with well-defined conditions, synchronized variations in higher-order properties of MCs and complicate microbial community succession mainly including enrichment and elimination of non-top competitors and unexpected turnover of top competitors, were observed. Quantification of PHA-accumulating function genes (phaC) revealed that the top competitors maintained the PHA synthesis by playing consecutive roles when the highly dynamic turnover occurred. Due to its specific physiological characteristics during the PHA-accumulating process, Thauera strain OTU 7 was found to be responsible for the fluctuating SVI, which threatened the robustness of the FF system. This trait was also responsible for its later competitive exclusion by the other PHA-producer, Paracoccus strain OTU 1. Deterministic processes dominated the entire FF system, resulting in the inevitable microbial community succession in the acclimation phase and maintenance of the stable PHA-accumulating function in the maturation phase. However, neutral processes, likely caused by predation from bacterial phages, also occurred, which led to the unpredictable temporal dynamics of the top competitors. Copyright © 2017. Published by Elsevier Ltd.

  16. 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.

  17. Ontogenetic foraging activity and feeding selectivity of the Brazilian endemic parrotfish Scarus zelindae

    OpenAIRE

    Pereira, Pedro H.C.; Santos, Marcus; Lippi, Daniel L.; Silva, Pedro

    2016-01-01

    Parrotfish are fundamental species in controlling algal phase-shifts and ensuring the resilience of coral reefs. Nevertheless, little is known on their ecological role in the south-western Atlantic Ocean. The present study analysed the ontogenetic foraging activity and feeding selectivity of the Brazilian endemic parrotfish Scarus zelindae using behavioural observation and benthic composition analyses. We found a significant negative relationship between fish size and feeding rates for S. zel...

  18. Radiogenetic effect of gamma irradiation under different ontogenetic states of sweet pepper

    International Nuclear Information System (INIS)

    Auni, S.; Daskalov, S.Kh.; Filev, K.A.

    1978-01-01

    In view of the practical utilization of the experimental mutagenesis, a detailed study of the radiosensitivity and the genetic effect on treatment at different phases of the ontogenetic development in the capsicum plant was carried out. Seven phases of the ontogenetic development were subjected to acute gamma irradiation with different doses: mature binuclear pollen, male and female gametophytes, zygotes, 15-day embryo, 30-day embryo, dry and germinated seeds. The mutagenic effect was recorded on the basis of the germination, fertility, number of fruits, number of sterile plants, weight of the seeds from the fruits, and frequency and spectrum of chlorophyll and morphological mutations. In all cases the radiobiological effect is increasing linearly in dependence of the applied dose. The analysis of the LD 50 , assessed for the different indices of radiation injuries, did not show significant differences in the radiosensitivity of the first five phases from the ontogenetic development. Dry seeds, however, are almost 10 times more radiosensitive. The germinated seeds occupy an intermediate position as regards the indicator of fertility only. The yield of both the chlorophyll and morphological mutations is increasing also linearly with the increasing of the dose at all phases of the ontogenetic development. The highest yield is observed at the phases of gametophytes and dry seeds and the smallest at the phase of germinated seeds. The phases of zygotes and embryo on the 15th day hold an intermediate position. In all investigated phases the amount of the morphological mutations is higher than that of the chlorophyll ones. (A.B.)

  19. Foraging strategies of the Galapagos Marine Iguana (Amblyrhynchus Cristatus): adapting behavioral rules to ontogenetic size change

    OpenAIRE

    Wikelski, Martin; Trillmich, Fritz

    1994-01-01

    Ontogenetic development in reptiles entails major changes in size-related foraging options. We studied the changes in foraging behavior of marine iguanas. In this species, size increases about twenty- to hundredfold from hatching to full adult size. The foraging strategy of marine iguanas was studied at Miedo on Santa Fe Island in the Galapagos archipelago During low tide, large marine iguanas (>250 mm snout vent length (SVL)) foraged more in the lower intertidal than small ones (

  20. Ontogenetic changes of lipofuscin-like pigments in the rat heart

    Czech Academy of Sciences Publication Activity Database

    Wilhelm, Jiří; Ošťádalová, Ivana

    2012-01-01

    Roč. 61, Suppl.1 (2012), S173-S179 ISSN 0862-8408 R&D Projects: GA ČR(CZ) GAP303/11/0298 Institutional research plan: CEZ:AV0Z50110509 Keywords : rat heart * ontogenetic development * lipofuscin-like pigments (LFP) * reactive oxygen species (ROS) * gender difference * right/left ventricle ratio Subject RIV: ED - Physiology Impact factor: 1.531, year: 2012

  1. Ontogenetic foraging activity and feeding selectivity of the Brazilian endemic parrotfish Scarus zelindae

    Directory of Open Access Journals (Sweden)

    Pedro H.C. Pereira

    2016-10-01

    Full Text Available Parrotfish are fundamental species in controlling algal phase-shifts and ensuring the resilience of coral reefs. Nevertheless, little is known on their ecological role in the south-western Atlantic Ocean. The present study analysed the ontogenetic foraging activity and feeding selectivity of the Brazilian endemic parrotfish Scarus zelindae using behavioural observation and benthic composition analyses. We found a significant negative relationship between fish size and feeding rates for S. zelindae individuals. Thus, terminal phase individuals forage with lower feeding rates compared to juveniles and initial phase individuals. The highest relative foraging frequency of S. zelindae was on epilithic algae matrix (EAM with similar values for juveniles (86.6%, initial phase (88.1% and terminal phase (88.6% individuals. The second preferred benthos for juveniles was sponge (11.6% compared with initial (4.5% and terminal life phases (1.3%. Different life phases of S. zelindae foraged on different benthos according to their availability. Based on Ivlev’s electivity index, juveniles selected EAM and sponge, while initial phase and terminal phase individuals only selected EAM. Our findings demonstrate that the foraging frequency of the endemic parrotfish S. zelindae is reduced according to body size and that there is a slight ontogenetic change in feeding selectivity. Therefore, ecological knowledge of ontogenetic variations on resource use is critical for the remaining parrotfish populations which have been dramatically reduced in the Southwestern Atlantic Ocean.

  2. Shape shifting predicts ontogenetic changes in metabolic scaling in diverse aquatic invertebrates.

    Science.gov (United States)

    Glazier, Douglas S; Hirst, Andrew G; Atkinson, David

    2015-03-07

    Metabolism fuels all biological activities, and thus understanding its variation is fundamentally important. Much of this variation is related to body size, which is commonly believed to follow a 3/4-power scaling law. However, during ontogeny, many kinds of animals and plants show marked shifts in metabolic scaling that deviate from 3/4-power scaling predicted by general models. Here, we show that in diverse aquatic invertebrates, ontogenetic shifts in the scaling of routine metabolic rate from near isometry (bR = scaling exponent approx. 1) to negative allometry (bR < 1), or the reverse, are associated with significant changes in body shape (indexed by bL = the scaling exponent of the relationship between body mass and body length). The observed inverse correlations between bR and bL are predicted by metabolic scaling theory that emphasizes resource/waste fluxes across external body surfaces, but contradict theory that emphasizes resource transport through internal networks. Geometric estimates of the scaling of surface area (SA) with body mass (bA) further show that ontogenetic shifts in bR and bA are positively correlated. These results support new metabolic scaling theory based on SA influences that may be applied to ontogenetic shifts in bR shown by many kinds of animals and plants. © 2015 The Author(s) Published by the Royal Society. All rights reserved.

  3. Chicken-sized oviraptorid dinosaurs from central China and their ontogenetic implications.

    Science.gov (United States)

    Lü, Junchang; Currie, Philip J; Xu, Li; Zhang, Xingliao; Pu, Hanyong; Jia, Songhai

    2013-02-01

    Oviraptorids are a group of specialized non-avian theropod dinosaurs that were generally one to 8 m in body length. New specimens of baby oviraptorids from the Late Cretaceous of Henan Province are some of the smallest individuals known. They include diagnostic characters such as the relative position of the antorbital fenestra and the external naris, distinct opening in the premaxilla anteroventral to the external naris, antorbital fossa partly bordered by premaxilla posterodorsally, lacrimal process of premaxilla does not contact the anterodorsal process of the lacrimal, parietal almost as long as frontal; in dorsal view, posterior margin forms a straight line between the postzygapophyses in each of the fourth and fifth cervicals; femur longer than ilium. They also elucidate the ontogenetic processes of oviraptorids, including fusion of cranial elements and changes in relative body proportions. Hind limb proportions are constant in oviraptorids, regardless of absolute body size or ontogenetic stage. This suggests a sedentary lifestyle that did not involve the pursuit of similar-sized prey. The functional implications for bite force and therefore dietary preferences are better understood through the study of such small animals. The comparison of the measurements of 115 skeletons indicates that oviraptorids maintain their hind limb proportions regardless of ontogenetic stage or absolute size, which is a pattern seen more commonly in herbivores than in carnivores. This may weakly support the hypothesis that oviraptorids are herbivores rather than active carnivores.

  4. Ontogenetic variations and feeding habits of a Neotropical annual fish from southern Brazil

    Directory of Open Access Journals (Sweden)

    Tatiana S. Dias

    Full Text Available ABSTRACT Knowing the feeding biology of a population and its ontogenetic aspects can help in understanding the functioning of fish assemblages, essential to the conservation of the habitat biodiversity in which these species are found. Annual fishes complete their life cycle in temporary aquatic environments, existing in adult stage only for brief annual periods. Changes in the feeding habits between different size classes could indicate that a species belongs to different feeding groups in different growth phases. The aim of this work was to characterize the diet of Cynopoecilus fulgens Costa, 2002 in a temporary flooded area in the coastal plain of southern Brazil, taking into consideration possible alterations in feeding habits in different body size classes caused by ontogenetic changes, to explain the coexistence of these individuals in a short space of time. The diet analysis indicated that C. fulgens is a generalist, consuming small crustaceans and autochthonous insects. Intraspecific differences in diet were determined when compared between nine classes of standard length. Adults fed mainly on autochthonous insects, and juveniles ingested mostly crustaceans, with the population being separated into two trophic groups: invertivores and invertivores with a tendency towards zooplanktivory. It is possible to conclude that the ontogenetic changes in the diet of C. fulgens are related to morphological restrictions due to the size of the individuals, since feeding competitive relations are probably not so evident.

  5. 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. ...

  6. 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...

  7. Ontogenetic scaling of locomotor kinetics and kinematics of the ostrich (Struthio camelus).

    Science.gov (United States)

    Smith, Nicola C; Jespers, Karin J; Wilson, Alan M

    2010-04-01

    Kinematic and kinetic parameters of running gait were investigated through growth in the ostrich, from two weeks up to 10 months of age, in order to investigate the effects of increasing body size. Ontogenetic scaling relationships were compared with published scaling relationships found to exist with increasing body size between species to determine whether dynamic similarity is maintained during growth. During the study, ostrich mass (M(b)) ranged from 0.7 kg to 108.8 kg. Morphological measurements showed that lengths scaled with positive allometry during growth (hip height proportional to M(b)(0.40); foot segment length proportional to M(b)(0.40); tarsometatarsus length proportional to M(b)(0.41); tibiotarsus length proportional to M(b)(0.38); femur length proportional to M(b)(0.37)), significantly exceeding the close to geometric scaling observed between mammalian and avian species of increasing body size. Scaling of kinematic variables largely agreed with predicted scaling for increasing size and demonstrated relationships close to dynamic similarity and, as such, ontogenetic scaling of locomotor parameters was similar to that observed with increasing body mass between species. However, the ways in which these scaling trends were achieved were very different, with ontogenetic scaling of locomotor mechanics largely resulting from simple scaling of the limb segments rather than postural changes, likely to be due to developmental constraints. Small deviations from dynamic similarity of kinematic parameters and a reduction in the predicted scaling of limb stiffness (proportional to M(b)(0.59)) were found to be accounted for by the positive allometric scaling of the limb during growth.

  8. Ontogenetic Responses of Calanus chilensis to Hypoxia from Northern Chile (23ºS), Humboldt Current Ecosystem

    Science.gov (United States)

    Ruz, P. M.; Hidalgo, P.; Escribano, R.; Franco-Cisterna, B.; Yebra, L.; Keister, J. E.

    2016-02-01

    Eastern Boundary Upwelling Systems are being subjected to expansion, intensification and shoaling of Oxygen Minimum Zones (OMZ's), as a result of ongoing climate change. To understand how dominant epipelagic copepods may respond to stressful conditions induced by low oxygen, we experimentally studied the effect of hypoxia over the stage-specific physiology of Calanus chilensis from the Mejillones Bay (23°S — 70°W), northern Chile, during the winters of 2013 and 2014. Females, eggs and nauplii (NI to NIV) of C. chilensis were incubated under hypoxia ( 0.7 mg O2 L-1) and normoxia ( 8.3 mg O2 L-1) conditions at a constant temperature of 14ºC as to estimate egg production rate (EPR), hatching success (HS) and naupliar growth and development time. Additionally, we estimated survivorship by using Neutral Red technique, and also examined female metabolism by measuring specific activity of the enzymes Aminoacyl-tRNA synthetases (spAARS) (growth index) and the electron transport system (spETS) (potential respiration). Survival of females and EPR were not significantly affected by dissolved oxygen (DO) conditions, coinciding with no significant changes in their metabolism. By contrast, HS was reduced from normoxia (70%) to hypoxia (30%), whereas naupliar growth (NI to NIII) was lower under hypoxia (0.155 ± 0.007 d-1) than normoxia (0.237 ± 0.006 d-1), resulting also in a longer development time, 6.490 ± 0.353 d and 4.238 ± 0.149 d, respectively. Most eggs and nauplii collected at the end of the experiments were alive, although a higher proportion of organisms were recovered in normoxia than hypoxia. Our results revealed stage-specific responses to hypoxia in C. chilensis and the importance of ontogenetic responses to variable levels of oxygenation in the upwelling zone.

  9. Ontogenetic variability in the feeding behavior of a marine amphipod in response to ocean acidification.

    Science.gov (United States)

    Benítez, Samanta; Duarte, Cristian; López, Jorge; Manríquez, Patricio H; Navarro, Jorge M; Bonta, Cesar C; Torres, Rodrigo; Quijón, Pedro A

    2016-11-15

    Global stressors like ocean acidification (OA) are expected to influence the quality or palatability of primary producers like algae. Such changes can trigger a response on algal consumers' feeding strategies, and this response may not necessarily be the same for the consumers during the ontogeny. We used a mesocosm's system to expose algae to current and projected OA conditions (390 and 1000ppm, respectively) and then compared the feeding behavior and absorption efficiency of juvenile and adult stages of the amphipod Orchestoidea tuberculata. Specifically, we measured consumption rates (with and without a choice) and absorption efficiency on algae exposed and not exposed to OA. Our results show that OA affect the amphipod's consumption and feeding preferences, and that these effects were related with the analyzed ontogenetic stage (juveniles versus adults). These results support the existence of an ontogenetic change in the response of this species and others similar marine invertebrates to OA, which highlight the need to incorporate different life stages in the study of OA or others global stressors. Copyright © 2016 Elsevier Ltd. All rights reserved.

  10. Genetic and ontogenetic variation in an endangered tree structures dependent arthropod and fungal communities.

    Directory of Open Access Journals (Sweden)

    Benjamin J Gosney

    Full Text Available Plant genetic and ontogenetic variation can significantly impact dependent fungal and arthropod communities. However, little is known of the relative importance of these extended genetic and ontogenetic effects within a species. Using a common garden trial, we compared the dependent arthropod and fungal community on 222 progeny from two highly differentiated populations of the endangered heteroblastic tree species, Eucalyptus morrisbyi. We assessed arthropod and fungal communities on both juvenile and adult foliage. The community variation was related to previous levels of marsupial browsing, as well as the variation in the physicochemical properties of leaves using near-infrared spectroscopy. We found highly significant differences in community composition, abundance and diversity parameters between eucalypt source populations in the common garden, and these were comparable to differences between the distinctive juvenile and adult foliage. The physicochemical properties assessed accounted for a significant percentage of the community variation but did not explain fully the community differences between populations and foliage types. Similarly, while differences in population susceptibility to a major marsupial herbivore may result in diffuse genetic effects on the dependent community, this still did not account for the large genetic-based differences in dependent communities between populations. Our results emphasize the importance of maintaining the populations of this rare species as separate management units, as not only are the populations highly genetically structured, this variation may alter the trajectory of biotic colonization of conservation plantings.

  11. Revisiting a model of ontogenetic growth: estimating model parameters from theory and data.

    Science.gov (United States)

    Moses, Melanie E; Hou, Chen; Woodruff, William H; West, Geoffrey B; Nekola, Jeffery C; Zuo, Wenyun; Brown, James H

    2008-05-01

    The ontogenetic growth model (OGM) of West et al. provides a general description of how metabolic energy is allocated between production of new biomass and maintenance of existing biomass during ontogeny. Here, we reexamine the OGM, make some minor modifications and corrections, and further evaluate its ability to account for empirical variation on rates of metabolism and biomass in vertebrates both during ontogeny and across species of varying adult body size. We show that the updated version of the model is internally consistent and is consistent with other predictions of metabolic scaling theory and empirical data. The OGM predicts not only the near universal sigmoidal form of growth curves but also the M(1/4) scaling of the characteristic times of ontogenetic stages in addition to the curvilinear decline in growth efficiency described by Brody. Additionally, the OGM relates the M(3/4) scaling across adults of different species to the scaling of metabolic rate across ontogeny within species. In providing a simple, quantitative description of how energy is allocated to growth, the OGM calls attention to unexplained variation, unanswered questions, and opportunities for future research.

  12. Ontogenetic development and sexual dimorphism of franciscana dolphin skull: A 3D geometric morphometric approach.

    Science.gov (United States)

    del Castillo, Daniela L; Flores, David A; Cappozzo, Humberto L

    2014-12-01

    The aim of this work was to study the postnatal ontogenetic development of Pontoporia blainvillei skull, identifying major changes on shape, and relating them to relevant factors in the life history of the species. We analyzed a complete ontogenetic series (73♂, 83♀) with three-dimensional geometric morphometric techniques. Immature dolphins showed a very well-developed braincase and a poorly developed rostrum, and the principal postnatal changes affected the rostrum and the temporal fossa, both structures implied functionally to the feeding apparatus, thus suggesting a specialized mode for catch fast prey in P. blainvillei. Osseous elements associated with sound production were already well developed on immature dolphins, suggesting the importance of this apparatus since the beginning of postnatal life. Sexual dimorphism was detected on both shape and size variables. Females were bigger than males, in accordance with previous studies. Shape differences between sexes were found on the posterior part of premaxillaries and external bony nares (P < 0.01), suggesting that this sexual dimorphism is related to differences on vocalization capabilities. © 2014 Wiley Periodicals, Inc.

  13. Ontogenetic allometry in the foot size of Oligoryzomys flavescens (Waterhouse, 1837 (Rodentia, Sigmodontinae

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    R. Maestri

    Full Text Available Ontogenetic allometry is the study of how the size or shape of certain structures changes over the course of an animal’s development. In this study, using Huxley's formula of allometric growth (1932, we assessed the changes in the rate of growth of the feet size of the sigmodontine rodent Oligoryzomys flavescens during its ontogeny and compared differences between males and females. We find evidence of a change of polarity during the ontogenetic development of the species, with the presence of positive allometry during pregnancy and negative allometry in adulthood. Moreover, we note the presence of sexual dimorphism in the size of the feet, in which males of the species have a higher rate of growth than females. This growth pattern is positively related to escape from predators in childhood in both sexes and, in adulthood, provides a higher encounter rate of females by males, due to the larger displacement of the latter. We suggest that both the forces of natural selection and sexual selection have acted to shape the evolution of foot size in this species.

  14. Ontogenetic allometry in the foot size of Oligoryzomys flavescens (Waterhouse, 1837) (Rodentia, Sigmodontinae).

    Science.gov (United States)

    Maestri, R; Fornel, R; Freitas, T R O; Marinho, J R

    2015-05-01

    Ontogenetic allometry is the study of how the size or shape of certain structures changes over the course of an animal's development. In this study, using Huxley's formula of allometric growth (1932), we assessed the changes in the rate of growth of the feet size of the sigmodontine rodent Oligoryzomys flavescens during its ontogeny and compared differences between males and females. We find evidence of a change of polarity during the ontogenetic development of the species, with the presence of positive allometry during pregnancy and negative allometry in adulthood. Moreover, we note the presence of sexual dimorphism in the size of the feet, in which males of the species have a higher rate of growth than females. This growth pattern is positively related to escape from predators in childhood in both sexes and, in adulthood, provides a higher encounter rate of females by males, due to the larger displacement of the latter. We suggest that both the forces of natural selection and sexual selection have acted to shape the evolution of foot size in this species.

  15. Alternative stable states generated by ontogenetic niche shift in the presence of multiple resource use.

    Directory of Open Access Journals (Sweden)

    Takefumi Nakazawa

    2011-02-01

    Full Text Available It has been suggested that when juveniles and adults use different resources or habitats, alternative stable states (ASS may exist in systems coupled by an ontogenetic niche shift. However, mainly the simplest system, i.e., the one-consumer-two-resource system, has been studied previously, and little is known about the development of ASS existing in more complex systems. Here, I theoretically investigated the development of ASS caused by an ontogenetic niche shift in the presence of multiple resource use. I considered three independent scenarios; (i additional resources, (ii multiple habitats, and (iii interstage resource sharing. The model analyses illustrate that relative balance between the total resource availability in the juvenile and adult habitats is crucial for the development of ASS. This balance is determined by factors such as local habitat productivity, subsidy inputs, colonization area, and foraging mobility. Furthermore, it is also shown that interstage resource sharing generally suppresses ASS. These results suggest that the anthropogenic impacts of habitat modifications (e.g., fragmentation and destruction or interaction modifications (e.g., changes in ontogeny and foraging behavior propagate through space and may cause or prevent regime shifts in the regional community structure.

  16. 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...

  17. 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).

  18. Ontogenetic study of the supraorbital region in modern humans: a longitudinal test of the spatial model.

    Science.gov (United States)

    Fiscella, Gabriela N; Smith, Fred H

    2006-06-01

    The structural significance of the hominid supraorbital torus and its morphological variation have always been a controversial topic in physical anthropology. Understanding the function of browridge variation in living and fossil human populations is relevant to questions of human evolution. This study utilizes radiograph images to evaluate the spatial model in modern humans during ontogeny. This structural model attributes variation in the supraorbital region to the positional relationship between the neurocranium and the orbits. The relationship between measurements of the antero-posterior supraorbital length and the factors specified in the spatial model were assessed by correlation and partial correlation analyses. Growth rates were also examined to study ontogenetic trajectories and infer aspects of developmental relationships between critical variables. Results agree with previous research supporting the existence of spatial influences between the neural and orbital-upper facial regions on browridge length during ontogeny.

  19. Dream content of Canadian males from adolescence to old age: An exploration of ontogenetic patterns.

    Science.gov (United States)

    Dale, Allyson; Lafrenière, Alexandre; De Koninck, Joseph

    2017-03-01

    The present study was a first look at the ontogenetic pattern of dream content across the lifespan for men. The participants included 50 Canadian men in each of 5 age groups, from adolescence to old age including 12-17, 18-24, 25-39, 40-64, and 65-85. The last age group included 31 participants, totaling 231 males. One dream per participant was scored by two independent judges using content analysis. Trend analysis was used to determine the lifespan-developmental pattern of the dream content categories. Results demonstrated a predominance of aggressive dream imagery in the adolescent age group in line with social-developmental research. These patterns of dream imagery reflect the waking developmental patterns as proposed by social theories and recognized features of aging. Limitations and suggestions for future research, including the examining of the developmental pattern of gender differences across the lifespan, are discussed. Copyright © 2017 Elsevier Inc. All rights reserved.

  20. Stimulus attributes of reactivated memory: alleviation of ontogenetic forgetting in rats is context specific.

    Science.gov (United States)

    Richardson, R; Riccio, D C; McKenney, M

    1988-03-01

    Numerous studies have shown that ontogenetic forgetting (infantile amensia) can be alleviated by a number of different types of reminder treatment. The present study extends the information about the alleviation of infantile amnesia by examining the "content" of the reactivated memory. Toward this purpose, one attribute of memory (environmental context) was examined in rats tested either shortly after training (preamnesic) or after 1-week retention interval. For the latter, a reactivation treatment was used to reverse infantile amnesia. At both intervals, a context shift resulted in impaired performance of a conditioned fear response. These findings demonstrate that environment context is an important component of the originally encoded memory as well as the reactivated amnestic memory. The implications of these results for both the reactivation of memory and general memory processes are discussed.

  1. Ontogenetically-regulated male sterility in tissue culture - induced and spontaneous sorghum mutants

    Directory of Open Access Journals (Sweden)

    Elkonin L.A.

    2003-01-01

    Full Text Available Variability of male fertility expression in the AS-1 line, a somaclonal variant obtained from tissue culture of CMS-plant, and in the progeny of revenant '124-1' obtained from fertile tiller, which developed on CMS-plant transferred from the field to the greenhouse, was investigated. Both revertants were characterized by similar expression of male fertility during plant ontogenesis: the panicle on the main tiller was almost completely sterile whereas formation of fertile pollen grains and seed set were observed on the panicles of the shoot tillers. A clear basipetal gradient of male fertility was manifested on all panicles: the base had significantly higher per cent of fertile pollen grains in comparison with the middle part, while in the top the anthers were either absent or had few sterile pollen grains. Such an ontogenetically-regulated restoration of male fertility was controlled by nuclear genes and could be transferred through the pollen in crosses with progenitor CMS-line. Growing of AS-1 plants in the growth chambers simultaneously under a long (16/8 and a short (12/12 daylength conditions demonstrated that differences of fertility level in different tillers was not caused by change of photoperiod during plant ontogenesis and functioning of photoperiod-sensitive fertility restoring gene. Whereas, the ontogenetically-regulated expression of male fertility in both revenants was temperature-dependent and was clearly manifested under relatively cool conditions during 2-week period before the beginning of anthesis of the first panicle (average daily temperature 21°C. The increase of the average daily temperature by 2-3 С resulted in sharp increase of male fertility level. Possibility of using AS-1 line in a new "two-line system" of hybrid seed production, which require only two lines (sterile mutant and fertility restorer, is discussed.

  2. Ontogenetic scaling of fore- and hind limb posture in wild chacma baboons (Papio hamadryas ursinus.

    Directory of Open Access Journals (Sweden)

    Biren A Patel

    Full Text Available Large-scale interspecific studies of mammals ranging between 0.04-280 kg have shown that larger animals walk with more extended limb joints. Within a taxon or clade, however, the relationship between body size and joint posture is less straightforward. Factors that may affect the lack of congruence between broad and narrow phylogenetic analyses of limb kinematics include limited sampling of (1 ranges of body size, and/or (2 numbers of individuals. Unfortunately, both issues are inherent in laboratory-based or zoo locomotion research. In this study, we examined the relationship between body mass and elbow and knee joint angles (our proxies of fore- and hind limb posture, respectively in a cross-sectional ontogenetic sample of wild chacma baboons (Papio hamadryas ursinus habituated in the De Hoop Nature Reserve, South Africa. Videos were obtained from 33 individuals of known age (12 to ≥ 108 months and body mass (2-29.5 kg during walking trials. Results show that older, heavier baboons walk with significantly more extended knee joints but not elbow joints. This pattern is consistent when examining only males, but not within the female sample. Heavier, older baboons also display significantly less variation in their hind limb posture compared to lighter, young animals. Thus, within this ontogenetic sample of a single primate species spanning an order of magnitude in body mass, hind limb posture exhibited a postural scaling phenomenon while the forelimbs did not. These findings may further help explain 1 why younger mammals (including baboons tend to have relatively stronger bones than adults, and 2 why humeri appear relatively weaker than femora (in at least baboons. Finally, this study demonstrates how field-acquired kinematics can help answer fundamental biomechanical questions usually addressed only in animal gait laboratories.

  3. Evidence of niche partitioning under ontogenetic influences among three morphologically similar siluriformes in small subtropical streams.

    Directory of Open Access Journals (Sweden)

    Karine Orlandi Bonato

    Full Text Available Ontogenetic influences in patterns of niche breadth and feeding overlap were investigated in three species of Siluriformes (Heptapterus sp., Rhamdia quelen and Trichomycterus poikilos aiming at understanding the species coexistence. Samplings were conducted bimonthly by electrofishing technique from June/2012 to June/2013 in ten streams of the northwestern state of Rio Grande do Sul, Brazil. The stomach contents of 1,948 individuals were analyzed by volumetric method, with 59 food items identified. In general Heptapterus sp. consumed a high proportion of Aegla sp., terrestrial plant remains and Megaloptera; R. quelen consumed fish, and Oligochaeta, followed by Aegla sp.; while the diet of T. poikilos was based on Simuliidae, Ephemeroptera and Trichoptera. Specie segregation was observed in the NMDS. Through PERMANOVA analysis feeding differences among species, and between a combination of species plus size classes were observed. IndVal showed which items were indicators of these differences. Niche breadth values were high for all species. The niche breadth values were low only for the larger size of R. quelen and Heptapterus sp. while T. poikilos values were more similar. Overall the species were a low feeding overlap values. The higher frequency of high feeding overlap was observed for interaction between Heptapterus sp. and T. poikilos. The null model confirmed the niche partitioning between the species. The higher frequency of high and intermediate feeding overlap values were reported to smaller size classes. The null model showed resource sharing between the species/size class. Therefore, overall species showed a resource partitioning because of the use of occasional items. However, these species share resources mainly in the early ontogenetic stages until the emphasized change of morphological characteristics leading to trophic niche expansion and the apparent segregation observed.

  4. Ecological interactions in dinosaur communities: influences of small offspring and complex ontogenetic life histories.

    Directory of Open Access Journals (Sweden)

    Daryl Codron

    Full Text Available Because egg-laying meant that even the largest dinosaurs gave birth to very small offspring, they had to pass through multiple ontogenetic life stages to adulthood. Dinosaurs' successors as the dominant terrestrial vertebrate life form, the mammals, give birth to live young, and have much larger offspring and less complex ontogenetic histories. The larger number of juveniles in dinosaur as compared to mammal ecosystems represents both a greater diversity of food available to predators, and competitors for similar-sized individuals of sympatric species. Models of population abundances across different-sized species of dinosaurs and mammals, based on simulated ecological life tables, are employed to investigate how differences in predation and competition pressure influenced dinosaur communities. Higher small- to medium-sized prey availability leads to a normal body mass-species richness (M-S distribution of carnivorous dinosaurs (as found in the theropod fossil record, in contrast to the right-skewed M-S distribution of carnivorous mammals (as found living members of the order Carnivora. Higher levels of interspecific competition leads to a left-skewed M-S distribution in herbivorous dinosaurs (as found in sauropods and ornithopods, in contrast to the normal M-S distribution of large herbivorous mammals. Thus, our models suggest that differences in reproductive strategy, and consequently ontogeny, explain observed differences in community structure between dinosaur and mammal faunas. Models also show that the largest dinosaurian predators could have subsisted on similar-sized prey by including younger life stages of the largest herbivore species, but that large predators likely avoided prey much smaller than themselves because, despite predicted higher abundances of smaller than larger-bodied prey, contributions of small prey to biomass intake would be insufficient to satisfy meat requirements. A lack of large carnivores feeding on small prey

  5. Ontogenetic convergence and evolution of foot morphology in European cave salamanders (Family: Plethodontidae

    Directory of Open Access Journals (Sweden)

    Nistri Annamaria

    2010-07-01

    Full Text Available Abstract Background A major goal in evolutionary biology is to understand the evolution of phenotypic diversity. Both natural and sexual selection play a large role in generating phenotypic adaptations, with biomechanical requirements and developmental mechanisms mediating patterns of phenotypic evolution. For many traits, the relative importance of selective and developmental components remains understudied. Results We investigated ontogenetic trajectories of foot morphology in the eight species of European plethodontid cave salamander to test the hypothesis that adult foot morphology was adapted for climbing. Using geometric morphometrics and other approaches, we found that developmental patterns in five species displayed little morphological change during growth (isometry, where the extensive interdigital webbing in adults was best explained as the retention of the juvenile morphological state. By contrast, three species exhibited significant allometry, with an increase in interdigital webbing during growth. Phylogenetic analyses revealed that multiple evolutionary transitions between isometry and allometry of foot webbing have occurred in this lineage. Allometric parameters of foot growth were most similar to those of a tropical species previously shown to be adapted for climbing. Finally, interspecific variation in adult foot morphology was significantly reduced as compared to variation among juveniles, indicating that ontogenetic convergence had resulted in a common adult foot morphology across species. Conclusions The results presented here provide evidence of a complex history of phenotypic evolution in this clade. The common adult phenotype exhibited among species reveals that selection plays an important part in generating patterns of foot diversity in the group. However, developmental trajectories arriving at this common morphology are distinct; with some species displaying developmental stasis (isometry, while others show an increase

  6. Ontogenetic criteria to distinguish vertebral types on the debated xenarthran synsacrum.

    Science.gov (United States)

    Galliari, Fernando C; Carlini, Alfredo A

    2015-05-01

    The presence of a synsacrum formed by the fusion of vertebrae that come into closed contact with the ilium and ischium is a feature that characterizes the clade Xenarthra. Nevertheless, the proper identity of each vertebral element that forms it is a matter of discussion. In this article, we provide ontogenetic information about skeletal ossification of the xenarthran synsacrum and define the position of the sacrocaudal limit within it. We analyzed the synsacrum of 25 specimens of nonadult and 101 adult armadillos and anteaters: Dasypus hybridus, D. novemcinctus, Chaetophractus vellerosus, C. villosus, Tamandua tetradactyla, and Myrmecophaga tridactyla. Two sets of vertebrae were identified: an anterior set, often attached to the iliac bones, in which transverse processes are originated mainly from an expansion of the base of the neural arches, and secondarily from a lateroventral ossification center. A posterior set is characterized by a series of vertebrae along which extra lateral ossifications (described here for the first time) are developed and form exclusively the transverse processes. Among armadillos, the sacrocaudal limit is set between the last vertebrae attached to the iliac bones and the first vertebrae that form the dorsal border of the sacroischial fenestra. In addition, anterior free caudals also showed extra lateral ossifications forming exclusively the transverse processes, supporting the notion that more posterior synsacrals are in fact caudal vertebrae that were incorporated to the synsacrum. In pilosans, the sacrocaudal limit is set between the first vertebrae that come into contact with the ischial bones and the immediately anterior one. However, the pattern of homologies is obscured by the low resolution in the ontogenetic sequence when compared to that of armadillos. © 2014 Wiley Periodicals, Inc.

  7. Ontogenetic scaling patterns and functional anatomy of the pelvic limb musculature in emus (Dromaius novaehollandiae

    Directory of Open Access Journals (Sweden)

    Luis P. Lamas

    2014-12-01

    Full Text Available Emus (Dromaius novaehollandiae are exclusively terrestrial, bipedal and cursorial ratites with some similar biomechanical characteristics to humans. Their growth rates are impressive, as their body mass increases eighty-fold from hatching to adulthood whilst maintaining the same mode of locomotion throughout life. These ontogenetic characteristics stimulate biomechanical questions about the strategies that allow emus to cope with their rapid growth and locomotion, which can be partly addressed via scaling (allometric analysis of morphology. In this study we have collected pelvic limb anatomical data (muscle architecture, tendon length, tendon mass and bone lengths and calculated muscle physiological cross sectional area (PCSA and average tendon cross sectional area from emus across three ontogenetic stages (n = 17, body masses from 3.6 to 42 kg. The data were analysed by reduced major axis regression to determine how these biomechanically relevant aspects of morphology scaled with body mass. Muscle mass and PCSA showed a marked trend towards positive allometry (26 and 27 out of 34 muscles respectively and fascicle length showed a more mixed scaling pattern. The long tendons of the main digital flexors scaled with positive allometry for all characteristics whilst other tendons demonstrated a less clear scaling pattern. Finally, the two longer bones of the limb (tibiotarsus and tarsometatarsus also exhibited positive allometry for length, and two others (femur and first phalanx of digit III had trends towards isometry. These results indicate that emus experience a relative increase in their muscle force-generating capacities, as well as potentially increasing the force-sustaining capacities of their tendons, as they grow. Furthermore, we have clarified anatomical descriptions and provided illustrations of the pelvic limb muscle–tendon units in emus.

  8. Ecological interactions in dinosaur communities: influences of small offspring and complex ontogenetic life histories.

    Science.gov (United States)

    Codron, Daryl; Carbone, Chris; Clauss, Marcus

    2013-01-01

    Because egg-laying meant that even the largest dinosaurs gave birth to very small offspring, they had to pass through multiple ontogenetic life stages to adulthood. Dinosaurs' successors as the dominant terrestrial vertebrate life form, the mammals, give birth to live young, and have much larger offspring and less complex ontogenetic histories. The larger number of juveniles in dinosaur as compared to mammal ecosystems represents both a greater diversity of food available to predators, and competitors for similar-sized individuals of sympatric species. Models of population abundances across different-sized species of dinosaurs and mammals, based on simulated ecological life tables, are employed to investigate how differences in predation and competition pressure influenced dinosaur communities. Higher small- to medium-sized prey availability leads to a normal body mass-species richness (M-S) distribution of carnivorous dinosaurs (as found in the theropod fossil record), in contrast to the right-skewed M-S distribution of carnivorous mammals (as found living members of the order Carnivora). Higher levels of interspecific competition leads to a left-skewed M-S distribution in herbivorous dinosaurs (as found in sauropods and ornithopods), in contrast to the normal M-S distribution of large herbivorous mammals. Thus, our models suggest that differences in reproductive strategy, and consequently ontogeny, explain observed differences in community structure between dinosaur and mammal faunas. Models also show that the largest dinosaurian predators could have subsisted on similar-sized prey by including younger life stages of the largest herbivore species, but that large predators likely avoided prey much smaller than themselves because, despite predicted higher abundances of smaller than larger-bodied prey, contributions of small prey to biomass intake would be insufficient to satisfy meat requirements. A lack of large carnivores feeding on small prey exists in mammals

  9. 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 ...

  10. Drive-by-Downloads

    Energy Technology Data Exchange (ETDEWEB)

    Narvaez, Julia; Endicott-Popovsky, Barbara E.; Seifert, Christian; Aval, Chiraag U.; Frincke, Deborah A.

    2010-02-01

    Abstract: Drive-by-downloads are malware that push, and then execute, malicious code on a client system without the user's consent. The purpose of this paper is to introduce a discussion of the usefulness of antivirus software for detecting the installation of such malware, providing groundwork for future studies. Client honeypots collected drive-by malware which was then evaluated using common antivirus products. Initial analysis showed that most of such antivirus products identified less than 70% of these highly polymorphic malware programs. Also, it was observed that the antivirus products tested, even when successfully detecting this malware, often failed to classify it, leading to the conclusion that further work could involve not only developing new behavioral detection technologies, but also empirical studies that improve general understanding of these threats. Toward that end, one example of malicious code was analyzed behaviorally to provide insight into next steps for the future direction of this research.

  11. Does investment in leaf defenses drive changes in leaf economic strategy? A focus on whole-plant ontogeny.

    Science.gov (United States)

    Mason, Chase M; Donovan, Lisa A

    2015-04-01

    Leaf defenses have long been studied in the context of plant growth rate, resource availability, and optimal investment theory. Likewise, one of the central modern paradigms of plant ecophysiology, the leaf economics spectrum (LES), has been extensively studied in the context of these factors across ecological scales ranging from global species data sets to temporal shifts within individuals. Despite strong physiological links between LES strategy and leaf defenses in structure, function, and resource investment, the relationship between these trait classes has not been well explored. This study investigates the relationship between leaf defenses and LES strategy across whole-plant ontogeny in three diverse Helianthus species known to exhibit dramatic ontogenetic shifts in LES strategy, focusing primarily on physical and quantitative chemical defenses. Plants were grown under controlled environmental conditions and sampled for LES and defense traits at four ontogenetic stages. Defenses were found to shift strongly with ontogeny, and to correlate strongly with LES strategy. More advanced ontogenetic stages with more conservative LES strategy leaves had higher tannin activity and toughness in all species, and higher leaf dry matter content in two of three species. Modeling results in two species support the conclusion that changes in defenses drive changes in LES strategy through ontogeny, and in one species that changes in defenses and LES strategy are likely independently driven by ontogeny. Results of this study support the hypothesis that leaf-level allocation to defenses might be an important determinant of leaf economic traits, where high investment in defenses drives a conservative LES strategy.

  12. Electrical machines and drives

    CERN Document Server

    Hindmarsh, John

    2002-01-01

    Recent years have brought substantial developments in electrical drive technology, with the appearance of highly rated, very-high-speed power-electronic switches, combined with microcomputer control systems.This popular textbook has been thoroughly revised and updated in the light of these changes. It retains its successful formula of teaching through worked examples, which are put in context with concise explanations of theory, revision of equations and discussion of the engineering implications. Numerous problems are also provided, with answers supplied.The third edition in

  13. USING OF MSC WITH DIFFERENT ONTOGENETIC MATURITY FOR CORRECTION OF CHRONIC FIBROSING LIVER DAMAGE

    Directory of Open Access Journals (Sweden)

    M. Y. Shagidulin

    2013-01-01

    Full Text Available Aim. To compare the effectiveness of MSC with different degree of ontogenetic maturity (MSC bone marrow – MSC BM and MSC umbilical cord – MSC UC on regenerative processes in injured liver. Methods. In 4 groups of experiments on Wistar rats (n = 80 with a model of fibrotic toxic liver damage (FLD it was studied the effect of MSCs with different degree of ontogenetic maturity on recovery processes at the regeneration of damaged liver: 1 gr. – Control, 2 gr. and 3 gr. introduction of MSC BM, included in Sphero®GEL-long in doses of 2.5 ×106 and 5.0 x 106 cells, respectively, and 4 gr. – introduction of MSC UC in the form of cell-spheroids (8–10 × 105 cells. The cells were injected into the damaged liver in 7 days after the end of FDL-modeling. The effect of cell therapy was studied during 180 days. The effectiveness of corrective therapy was evaluated by the results of functional and morphological investigations of livers (histological control of parenchymal and nonparenchy- mal liver tissue. Results. MSC BM in both doses and MSC UC contributed to a more rapid normalization of liver enzyme indices compared with the control (1 gr., but the differences in the rate of recovery of disturbed enzymatic liver functions between groups 2, 3 and 4 – were absent. In 90 days after the cell application it was determined a more pronounced recovery activity of cells in groups 3 and 4; in 180 days the more pronounced activation of recovery processes was observed in group 3; but in group 4 the sclerotic processes were more pro- nounced in this period. Conclusion. For the induction of recovery processes in damage liver it is advisable not to use the MSC UC, but to use MSC BM in the Sphero®GEL, because MSC BM exert not only local but also systemic immune-regulatory effect, increasing the pool of T-reg. cells, which are additional carriers of regenera- tion information in organism. 

  14. Effects of prey size and foraging mode on the ontogenetic change in feeding niche ofColostethus stepheni (Anura: Dendrobatidae).

    Science.gov (United States)

    Lima, Albertina P; Moreira, Gloria

    1993-03-01

    The feeding niche ofColostethus stepheni changes during ontogeny. Small individuals eat small arthropods, principally mites and collembolans, and larger frogs eat bigger prey of other types. The shift in prey types is not a passive effect of selection for bigger prey. There is a strong relationship between electivity for prey types and frog size, independent of electivity for prey size. Four indices of general activity during foraging (number of movements, velocity, total area utilized and time spent moving), which are associated with electivity for prey types in adult frogs and lizards, did not predict the ontogenetic change in the diet ofC. stepheni. Apparently, the behavioral changes that cause the ontogenetic change inC. stepheni are more subtle than shifts in general activity during foraging. Studies of niche partitioning in communities of anurans that do not take into consideration ontogenetic changes in diet and seasonal changes in the size structures of populations present a partial and possibly erroneous picture of the potential interactions among species.

  15. Current drive for rotamak plasmas

    Indian Academy of Sciences (India)

    Abstract. Experiments which have been undertaken over a number of years have shown that a rotating magnetic field can drive a significant non-linear Hall current in a plasma. Successful experiments of this concept have been made with a device called rotamak. In its original configuration this device was a field reversed ...

  16. Ontogenetic ritualization of primate gesture as a case study in dyadic brain modeling.

    Science.gov (United States)

    Gasser, Brad; Cartmill, Erica A; Arbib, Michael A

    2014-01-01

    This paper introduces dyadic brain modeling - the simultaneous, computational modeling of the brains of two interacting agents - to explore ways in which our understanding of macaque brain circuitry can ground new models of brain mechanisms involved in ape interaction. Specifically, we assess a range of data on gestural communication of great apes as the basis for developing an account of the interactions of two primates engaged in ontogenetic ritualization, a proposed learning mechanism through which a functional action may become a communicative gesture over repeated interactions between two individuals (the 'dyad'). The integration of behavioral, neural, and computational data in dyadic (or, more generally, social) brain modeling has broad application to comparative and evolutionary questions, particularly for the evolutionary origins of cognition and language in the human lineage. We relate this work to the neuroinformatics challenges of integrating and sharing data to support collaboration between primatologists, neuroscientists and modelers that will help speed the emergence of what may be called comparative neuro-primatology.

  17. Vertical movement patterns and ontogenetic niche expansion in the tiger shark, Galeocerdo cuvier.

    Science.gov (United States)

    Afonso, André S; Hazin, Fábio H V

    2015-01-01

    Sharks are top predators in many marine ecosystems and can impact community dynamics, yet many shark populations are undergoing severe declines primarily due to overfishing. Obtaining species-specific knowledge on shark spatial ecology is important to implement adequate management strategies for the effective conservation of these taxa. This is particularly relevant concerning highly-mobile species that use wide home ranges comprising coastal and oceanic habitats, such as tiger sharks, Galeocerdo cuvier. We deployed satellite tags in 20 juvenile tiger sharks off northeastern Brazil to assess the effect of intrinsic and extrinsic factors on depth and temperature usage. Sharks were tracked for a total of 1184 d and used waters up to 1112 m in depth. The minimum temperature recorded equaled 4°C. All sharks had a clear preference for surface (sharks used mostly shallow (sharks spending considerably more time in surface (shark habitat was observed, with generalized linear models estimating a ~4-fold increase in maximum diving depth from 150- to 300-cm size-classes. The time spent in the upper 5 m of the water column did not vary ontogenetically but shark size was the most important factor explaining the utilization of deeper water layers. Young-of-the-year tiger sharks seem to associate with shallow, neritic habitats but they progressively move into deeper oceanic habitats as they grow larger. Such an early plasticity in habitat use could endow tiger sharks with access to previously unavailable prey, thus contributing to a wider ecological niche.

  18. Humeral torsion revisited: a functional and ontogenetic model for populational variation.

    Science.gov (United States)

    Cowgill, Libby W

    2007-12-01

    Anthropological interest in humeral torsion has a long history, and several functional explanations for observed variation in the orientation of the humeral head have been proposed. Recent clinical studies have revived this topic by linking patterns of humeral torsion to habitual activities such as overhand throwing. However, the precise functional implications and ontogenetic history of humeral torsion remain unclear. This study examines the ontogeny of humeral torsion in a large sample of primarily immature remains from six different skeletal collections (n = 407). The results of this research confirm that humeral torsion displays consistent developmental variation within all populations of growing children; neonates display relatively posteriorly oriented humeral heads, and the level of torsion declines steadily into adulthood. As in adults, variation in the angle of humeral torsion in immature individuals varies by population, and these differences arise early in development. However, when examined in the context of the developing muscles of the shoulder complex, it becomes apparent that variation in the angle of humeral torsion is not necessarily related to specific habitual activities. Variability in this feature is more likely caused by a generalized functional imbalance between muscles of medial and lateral rotation that can be produced by a wide variety of upper limb activity patterns during growth. (c) 2007 Wiley-Liss, Inc.

  19. Spatial and Ontogenetic Variation in Mercury in Lake Superior Basin Sea Lamprey (Petromyzon marinus).

    Science.gov (United States)

    Moses, Sara K; Polkinghorne, Christine N; Mattes, William P; Beesley, Kimberly M

    2018-01-01

    Mercury concentrations were measured in eggs, larvae, and adult spawning-phase sea lampreys (Petromyzon marinus) collected in tributaries of Lake Superior to investigate spatial and ontogenetic variation. There were significant differences in mercury concentrations between all three life stages, with levels highest in adults (mean = 3.01 µg/g), followed by eggs (mean = 0.942 µg/g), and lowest in larvae (mean = 0.455 µg/g). There were no significant differences in mercury concentrations by location for any life stage or by sex in adults. Mercury was not correlated with adult or larval lamprey length or mass. Mercury levels in adult lampreys exceeded U.S. and Canadian federal guidelines for human consumption. Mercury concentrations in all life stages exceeded criteria for the protection of piscivorous wildlife, posing a threat to local fish, birds, and mammals. High mercury levels in adult lampreys combined with their semelparous life history make them a potential source of lake-derived mercury to spawning streams.

  20. Ontogenetic Variation of Individual and Total Capsaicinoids in Malagueta Peppers (Capsicum frutescens) during Fruit Maturation.

    Science.gov (United States)

    Fayos, Oreto; de Aguiar, Ana Carolina; Jiménez-Cantizano, Ana; Ferreiro-González, Marta; Garcés-Claver, Ana; Martínez, Julián; Mallor, Cristina; Ruiz-Rodríguez, Ana; Palma, Miguel; Barroso, Carmelo G; Barbero, Gerardo F

    2017-05-03

    The ontogenetic variation of total and individual capsaicinoids (nordihydrocapsaicin (n-DHC), capsaicin (C), dihydrocapsaicin (DHC), homocapsaicin (h-C) and homodihydrocapsaicin (h-DHC)) present in Malagueta pepper ( Capsicum frutescens ) during fruit ripening has been studied. Malagueta peppers were grown in a greenhouse under controlled temperature and humidity conditions. Capsaicinoids were extracted using ultrasound-assisted extraction (UAE) and the extracts were analyzed by ultra-performance liquid chromatography (UHPLC) with fluorescence detection. A significant increase in the total content of capsaicinoids was observed in the early days (between 12 and 33). Between day 33 and 40 there was a slight reduction in the total capsaicinoid content (3.3% decrease). C was the major capsaicinoid, followed by DHC, n-DHC, h-C and h-DHC. By considering the evolution of standardized values of the capsaicinoids it was verified that n-DHC, DHC and h-DHC (dihydrocapsaicin-like capsaicinoids) present a similar behavior pattern, while h-C and C (capsaicin-like capsaicinoids) show different evolution patterns.

  1. Ontogenetic shifts in morphology and resource use of cisco Coregonus artedi.

    Science.gov (United States)

    Muir, A M; Vecsei, P; Pratt, T C; Krueger, C C; Power, M; Reist, J D

    2013-02-01

    Two previously described lacustrine cisco Coregonus spp. morphs [i.e. a small (cisco Coregonus artedi. Geometric body shape did not differ between the two size classes nor could they be differentiated by 24 size-corrected linear measurements, indicating that the two groups had similar phenotypes. Strong, positive correlations between all linear characters and geometric centroid size (a composite variable of fish body length, mass and age) suggested that body morphology changed with age as fish grew. Total gillraker number (N(GR)) increased with L(F) according to: N(GR) = 36.3 + 0.034L(F). Differences in gillraker number and phenotype with age and size were explained by shifts in habitat and trophic resource use. Relative abundance within 0-30, 30-60, 60-90 and >90 m depth strata differed between size classes suggesting that morphology changed when fish shifted their habitat as they grew older. Large C. artedi had lower δ(13)C and slightly higher δ(15)N, indicating greater reliance on pelagic prey resources (i.e. more or larger zooplankton, such as Mysis spp.), compared to small C. artedi, which relied slightly more on benthic prey. Gillraker shape and number have always been used as key diagnostic characters in coregonine taxonomy; based on the findings presented here, ontogenetic shifts should be accounted for in resulting classifications. © 2013 The Authors. Journal of Fish Biology © 2013 The Fisheries Society of the British Isles.

  2. Are tree ontogenetic structure and allometric relationship independent of vegetation formation type? A case study with Cordia oncocalyx in the Brazilian caatinga

    Science.gov (United States)

    Silveira, Andréa P.; Martins, Fernando R.; Araújo, Francisca S.

    2012-08-01

    In temperate and tropical rainforests, ontogenetic structure and allometry during tree ontogeny are often associated with light gradients. Light is not considered a limiting resource in deciduous thorny woodland (DTW), but establishment and growth occur during a short rainy period, when the canopy is fully leaved and light in the understory may be modified. Our aim was to investigate whether the light gradient in DTW and the biomechanical limitations of tree growth would be enough to produce an ontogenetic structure and allometric growth similar to rainforest canopy trees. We investigated the ontogenetic stages and diameter-height relationship of Cordia oncocalyx (Boraginaceae), a dominant canopy tree of the DTW of semiarid northeastern Brazil. We tagged, measured and classified the ontogenetic stages of 2.895 individuals in a 1 ha area (5°6'58.1″S and 40°52'19.4″W). In the rainy season only 4.7% of the light falling on the canopy reached the ground. Initial ontogenetic stages, mainly infant (50.9%) and seedling (42.1%), were predominant in the population, with the remaining 7% distributed among juvenile, immature, virginile and reproductive. The ontogenetic structure was similar to that of rainforest tree species, but the population formed both permanent seed and infant banks in response to long dry periods and erratic rainy spells. Like many other Boraginaceae tree species in tropical rainforests, C. oncocalyx has a Prévost architectural model, but allometric growth was quite different from rainforest trees. C. oncocalyx invested slightly more in diameter at first, then in height and finally invested greatly in diameter and attained an asymptotic height. The continued high investment in diameter growth at late stages and the asymptotic height point to low tree density and more frequent xylem embolism as the main drivers of tree allometric shape in DTW. This indicates that tree ontogenetic structure and allometric relationships depend on vegetation

  3. Hurried driving: Relationship to distress tolerance, driver anger, aggressive and risky driving in college students.

    Science.gov (United States)

    Beck, Kenneth H; Daughters, Stacey B; Ali, Bina

    2013-03-01

    Being a hurried driver is associated with a variety of risky driving behaviors, yet the mechanisms underlying this behavior remain unknown. Distress tolerance, defined as an individual's capability to experience and endure negative emotional states, was examined as a predictor of hurried driving among 769 college students. Results indicate that after controlling for age, gender, race, ethnicity, the student's year in school, their grade point average, driving frequency, angry driving, aggressive driving as well as other forms of self-reported risky driving; hurried driving was significantly associated with lower levels of distress tolerance. Hurried drivers also reported greater levels of frustration and impatience with other drivers, suggesting that they have difficulty in withstanding or coping with negative psychological states when driving. Traditional traffic safety campaigns that emphasize enforcement may be less successful with these drivers. The need to develop campaigns that address the affective coping abilities that contribute to this behavioral pattern is discussed. Copyright © 2012 Elsevier Ltd. All rights reserved.

  4. Extended driving impairs nocturnal driving performances.

    Directory of Open Access Journals (Sweden)

    Patricia Sagaspe

    Full Text Available Though fatigue and sleepiness at the wheel are well-known risk factors for traffic accidents, many drivers combine extended driving and sleep deprivation. Fatigue-related accidents occur mainly at night but there is no experimental data available to determine if the duration of prior driving affects driving performance at night. Participants drove in 3 nocturnal driving sessions (3-5 am, 1-5 am and 9 pm-5 am on open highway. Fourteen young healthy men (mean age [+/-SD] = 23.4 [+/-1.7] years participated Inappropriate line crossings (ILC in the last hour of driving of each session, sleep variables, self-perceived fatigue and sleepiness were measured. Compared to the short (3-5 am driving session, the incidence rate ratio of inappropriate line crossings increased by 2.6 (95% CI, 1.1 to 6.0; P<.05 for the intermediate (1-5 am driving session and by 4.0 (CI, 1.7 to 9.4; P<.001 for the long (9 pm-5 am driving session. Compared to the reference session (9-10 pm, the incidence rate ratio of inappropriate line crossings were 6.0 (95% CI, 2.3 to 15.5; P<.001, 15.4 (CI, 4.6 to 51.5; P<.001 and 24.3 (CI, 7.4 to 79.5; P<.001, respectively, for the three different durations of driving. Self-rated fatigue and sleepiness scores were both positively correlated to driving impairment in the intermediate and long duration sessions (P<.05 and increased significantly during the nocturnal driving sessions compared to the reference session (P<.01. At night, extended driving impairs driving performances and therefore should be limited.

  5. Control rod drive mechanism

    International Nuclear Information System (INIS)

    Nakamura, Akira.

    1981-01-01

    Purpose: To ensure the scram operation of a control rod by the reliable detection for the position of control rods. Constitution: A permanent magnet is provided to the lower portion of a connecting rod in engagement with a control rod and a tube having a plurality of lead switches arranged axially therein in a predetermined pitch is disposed outside of the control rod drives. When the control rod moves upwardly in the scram operation, the lead switches are closed successively upon passage of the permanent magnet to operate the electrical circuit provided by way of each of the lead switches. Thus, the position for the control rod during the scram can reliably be determined and the scram characteristic of the control rod can be recognized. (Furukawa, Y.)

  6. The ontogenetic changes in the thermal properties of blubber from Atlantic bottlenose dolphin Tursiops truncatus.

    Science.gov (United States)

    Dunkin, Robin C; McLellan, William A; Blum, James E; Pabst, D Ann

    2005-04-01

    In Atlantic bottlenose dolphins Tursiops truncatus, both the thickness and lipid content of blubber vary across ontogeny and across individuals of differing reproductive and nutritional status. This study investigates how these changes in blubber morphology and composition influence its thermal properties. Thermal conductivity (W m(-1) deg.(-1), where deg. is degrees C) and thermal insulation (m(2) deg. W(-1)) of dolphin blubber were measured in individuals across an ontogenetic series (fetus through adult, N=36), pregnant females (N=4) and emaciated animals (N=5). These thermal properties were determined by the simultaneous use of two common experimental approaches, the heat flux disc method and the standard material method. Thickness, lipid and water content were measured for each blubber sample. Thermal conductivity and insulation varied significantly across ontogeny. Blubber from fetuses through sub-adults was less conductive (range=0.11-0.13+/-0.02 W m(-1) deg.(-1)) than that of adults (mean=0.18 W m(-1) deg.(-1)). The conductivity of blubber from pregnant females was similar to non-adult categories, while that of emaciated animals was significantly higher (0.24 +/- 0.04 W m deg.(-1)) than all other categories. Blubber from sub-adults and pregnant females had the highest insulation values while fetuses and emaciated animals had the lowest. In nutritionally dependent life history categories, changes in blubber's thermal insulation were characterized by stable blubber quality (i.e. conductivity) and increased blubber quantity (i.e. thickness). In nutritionally independent animals, blubber quantity remained stable while blubber quality varied. A final, unexpected observation was that heat flux measurements at the deep blubber surface were significantly higher than that at the superficial surface, a pattern not observed in control materials. This apparent ability to absorb heat, coupled with blubber's fatty acid composition, suggest that dolphin integument may

  7. Ontogenetic stage, plant vigor and sex mediate herbivory loads in a dioecious understory herb

    Science.gov (United States)

    Selaković, Sara; Vujić, Vukica; Stanisavljević, Nemanja; Jovanović, Živko; Radović, Svetlana; Cvetković, Dragana

    2017-11-01

    Plant-herbivore interactions can be mediated by plant apparency, defensive and nutritional quality traits that change through plant ontogeny, resulting in age-specific herbivory. In dioecious species, opposing allocation patterns in defense may lead to sex-biased herbivory. Here, we examine how onto stage and plant sex determine levels of herbivore damage in understory herb Mercurialis perennis under field conditions. We analyzed variation in plant size (height, total leaf area), physical (specific leaf area) and chemical (total phenolic and condensed tannins contents) defense, and nutritional quality (total water, soluble protein and nonstructural carbohydrate contents) during the shift from reproductive to post-reproductive stage. Furthermore, we explored correlations between the analyzed traits and levels of foliar damage. Post-reproductive plants had lower levels of chemical defense, and larger leaf area removed, in spite of having lower nutritive quality. Opposing patterns of intersexual differences were detected in protein and phenolic contents during reproductive stage, while in post-reproductive stage total leaf area was sexually dimorphic. Female-biased herbivory was apparent only after reproduction. Plant size parameters combined with condensed tannins content determined levels of foliar damage during post-reproductive stage, while the only trait covarying with herbivory in reproductive stage was total nonstructural carbohydrate content. Our results support claims of optimal defense theory - sensitive stage of reproduction was better defended. We conclude that different combinations of plant traits mediated interactions with herbivores in mature stages. Differences in reproductive allocation between the sexes may not immediately translate into different levels of damage, stressing the need for considering different ontogenetic stages when exploring sex bias in herbivory.

  8. Ontogenetic changes in radiation use efficiency of sunflower (Helianthus annuus L.) crops

    International Nuclear Information System (INIS)

    Trapani, N.; Hall, A.J.; Sadras, V.O.; Vilella, F.

    1992-01-01

    Radiation use efficiency (ϵ) values for sunflower were derived using data from periodic determinations of crop aerial or total (aerial + root) biomass and radiation interception in two experiments conducted at Junin and Buenos Aires, Argentina. Analysis showed that three distinct phases, each characterized by a different value of ϵ, could be distinquished. The phases were establishment (0–47 days after emergence (dae)), rapid growth (47 dae-anthesis) and postanthesis (anthesis-physiologcial maturity). The crops had reached the bud-visible stage and intercepted at least 85% of incident radiation by 47 dae. Efficiency values based on aerial biomass were highest during the rapid growth (ϵrg = 2.4 ± 0.22 g/MJ PAR) phase and lower during the establishment (ϵ e = 1.01 ± 0.25 g/MJ PAR) and postanthesis (ϵ pa = 1.3 ± 0.15 g/MJ PAR) phases. The differences between ϵ pa and ϵ rg are attributed to the increased respiration load, high synthesis costs of the oil-rich grains and leaf senescence during grain filling. The value of ϵe was less than of ϵ rg even when efficiencies were calculated on the basis of total crop biomass (i.e. including root biomass). Hence, ontogenetic changes in partitioning of biomass between the root and aerial organs do not seem to be the cause of the changes in the value of ϵ. No variations in photosynthetic capacity with leaf position could be found, and it is concluded that the most likely reason for the lower values of ϵ e lies in saturation of canopy photosynthesis at less than full sunlight while crop cover is incomplete. (author)

  9. Ontogenetic variations in the venom proteome of the Amazonian snake Bothrops atrox

    Directory of Open Access Journals (Sweden)

    Sousa Marcelo V

    2006-05-01

    Full Text Available Abstract Background Bothrops atrox is responsible for the majority of snakebite accidents in the Brazilian Amazon region. Previous studies have demonstrated that the biological and pharmacological activities of B. atrox venom alter with the age of the animal. Here, we present a comparative proteome analysis of B. atrox venom collected from specimens of three different stages of maturation: juveniles, sub-adults and adults. Results Optimized conditions for two-dimensional gel electrophoresis (2-DE of pooled venom samples were achieved using immobilized pH gradient (IPG gels of non-linear 3–10 pH range during the isoelectric focusing step and 10–20% gradient polyacrylamide gels in the second dimension. Software-assisted analysis of the 2-DE gels images demonstrated differences in the number and intensity of spots in juvenile, sub-adult and adult venoms. Although peptide mass fingerprinting (PMF failed to identify even a minor fraction of spots, it allowed us to group spots that displayed similar peptide maps. The spots were subjected to a combination of tandem mass spectrometry and Mascot and MS BLAST database searches that identified several classes of proteins, including metalloproteinases, serine proteinases, lectins, phospholipases A2, L-amino oxidases, nerve growth factors, vascular endothelial growth factors and cysteine-rich secretory proteins. Conclusion The analysis of B. atrox samples from specimens of different ages by 2-DE and mass spectrometry suggested that venom proteome alters upon ontogenetic development. We identified stage specific and differentially expressed polypeptides that may be responsible for the activities of the venom in each developmental stage. The results provide insight into the molecular basis of the relation between symptomatology of snakebite accidents in humans and the venom composition. Our findings underscore the importance of the use of venoms from individual specimen at various stages of maturation for

  10. HARMONIC DRIVE SELECTION

    Directory of Open Access Journals (Sweden)

    Piotr FOLĘGA

    2014-03-01

    Full Text Available The variety of types and sizes currently in production harmonic drive is a problem in their rational choice. Properly selected harmonic drive must meet certain requirements during operation, and achieve the anticipated service life. The paper discusses the problems associated with the selection of the harmonic drive. It also presents the algorithm correct choice of harmonic drive. The main objective of this study was to develop a computer program that allows the correct choice of harmonic drive by developed algorithm.

  11. Ontogenetic development of the inner ear saccule and utricle in the Lusitanian toadfish: Potential implications for auditory sensitivity.

    Science.gov (United States)

    Chaves, Patrícia P; Valdoria, Ciara M C; Amorim, M Clara P; Vasconcelos, Raquel O

    2017-09-01

    Studies addressing structure-function relationships of the fish auditory system during development are sparse compared to other taxa. The Batrachoididae has become an important group to investigate mechanisms of auditory plasticity and evolution of auditory-vocal systems. A recent study reported ontogenetic improvements in the inner ear saccule sensitivity of the Lusitanian toadfish, Halobatrachus didactylus, but whether this results from changes in the sensory morphology remains unknown. We investigated how the macula and organization of auditory receptors in the saccule and utricle change during growth in this species. Inner ear sensory epithelia were removed from the end organs of previously PFA-fixed specimens, from non-vocal posthatch fry (23 cm). Epithelia were phalloidin-stained and analysed for area, shape, number and orientation patterns of hair cells (HC), and number and size of saccular supporting cells (SC). Saccular macula area expanded 41x in total, and significantly more (relative to body length) among vocal juveniles (2.3-2.9 cm). Saccular HC number increased 25x but HC density decreased, suggesting that HC addition is slower relative to epithelial growth. While SC density decreased, SC apical area increased, contributing to the epithelial expansion. The utricule revealed increased HC density (striolar region) and less epithelial expansion (5x) with growth, contrasting with the saccule that may have a different developmental pattern due to its larger size and main auditory functions. Both macula shape and HC orientation patterns were already established in the posthatch fry and retained throughout growth in both end organs. We suggest that previously reported ontogenetic improvements in saccular sensitivity might be associated with changes in HC number (not density), size and/or molecular mechanisms controlling HC sensitivity. This is one of the first studies investigating the ontogenetic development of the saccule and utricle in a vocal fish and

  12. Impact of environmental diversity of hunting complexes in the Lublin region on ontogenetic quality indicators in roe deer (Capreolus capreolus).

    Science.gov (United States)

    Czyżowski, Piotr; Drozd, Leszek; Karpiński, Mirosław; Tajchman, Katarzyna; Goleman, Małgorzata; Wojtaś, Justyna; Zieliński, Damian

    2018-01-01

    Populations of game are not confined to single ecosystems but function within higher-order units, e.g. ecological landscape. The basis for the establishment of the hunting complexes was the assumption that the existing game hunting grounds, i.e. the basic units implementing game management, are too small and do not cover the natural areas inhabited by game populations. Roe deer are flexible species and easily adapt to various site conditions, so they inhabit many different habitats, from large forest complexes, through small in-field tree stands and shrubs, to treeless grounds and field monocultures. The aim of the study was to determine a possible impact of environmental conditions prevailing in the hunting complexes of the Regional Directorate of State Forests (RDLP in Lublin) on the ontogenetic quality of roe deer. The study was conducted on 518 European roe deer ( Capreolus capreolus ) aged from 4 to 7 years (379 bucks and 139 does) harvested within hunting seasons 2010/2011-2013/2014. The results have shown that animals originating from areas with greater forest cover and denser stands are characterised by lower values of the mean ontogenetic quality parameters (carcase weight, kidney fat index, chest girth, weight of antlers) in comparison with animals from typical agricultural areas with fragmented forest complexes. These results indicate that, even in the case of such a eurytopic species as the roe deer, the ontogenetic quality differs between individual hunting complexes. The study has proved that strategies for hunting management of the roe deer should take into account the impact of the landscape structure, which provides a rationale behind creation of hunting complexes.

  13. Retrospective characterization of ontogenetic shifts in killer whale diets via δ13C and δ15N analysis of teeth

    Science.gov (United States)

    Newsome, Seth D.; Etnier, Michael A.; Monson, Daniel H.; Fogel, Marilyn L.

    2009-01-01

    Metabolically inert, accretionary structures such as the dentin growth layers in teeth provide a life history record of individual diet with near-annual resolution. We constructed ontogenetic δ13C and δ15N profiles by analyzing tooth dentin growth layers from 13 individual killer whales Orcinus orca collected in the eastern northeast Pacific Ocean between 1961 and 2003. The individuals sampled were 6 to 52 yr old, representing 2 ecotypes—resident and transient—collected across ~25° of latitude. The average isotopic values of transient individuals (n = 10) are consistent with a reliance on mammalian prey, while the average isotopic values of residents (n = 3) are consistent with piscivory. Regardless of ecotype, most individuals show a decrease in δ15N values of ~2.5‰ through the first 3 yr of life, roughly equivalent to a decrease of one trophic level. We interpret this as evidence of gradual weaning, after which, ontogenetic shifts in isotopic values are highly variable. A few individuals (n = 2) maintained relatively stable δ15N and δ13C values throughout the remainder of their lives, whereas δ15N values of most (n = 11) increased by ~1.5‰, suggestive of an ontogenetic increase in trophic level. Significant differences in mean δ13C and δ15N values among transients collected off California suggest that individuality in prey preferences may be prevalent within this ecotype. Our approach provides retrospective individual life history and dietary information that cannot be obtained through traditional field observations of free-ranging and elusive species such as killer whales, including unique historic ecological information that pre-dates modern studies. By providing insights into individual diet composition, stable isotope analysis of teeth and/or bones may be the only means of evaluating a number of hypothesized historical dietary shifts in killer whales of the northeast Pacific Ocean

  14. Evaluating hair as a predictor of blood mercury: the influence of ontogenetic phase and life history in pinnipeds

    Science.gov (United States)

    Peterson, Sarah H.; McHuron, Elizabeth A.; Kennedy, Stephanie N.; Ackerman, Joshua T.; Rea, Lorrie D.; Castellini, J. Margaret; O'Hara, Todd M.; Costa, Daniel P.

    2016-01-01

    Mercury (Hg) biomonitoring of pinnipeds increasingly utilizes nonlethally collected tissues such as hair and blood. The relationship between total Hg concentrations ([THg]) in these tissues is not well understood for marine mammals, but it can be important for interpretation of tissue concentrations with respect to ecotoxicology and biomonitoring. We examined [THg] in blood and hair in multiple age classes of four pinniped species. For each species, we used paired blood and hair samples to quantify the ability of [THg] in hair to predict [THg] in blood at the time of sampling and examined the influence of varying ontogenetic phases and life history of the sampled animals. Overall, we found that the relationship between [THg] in hair and blood was affected by factors including age class, weaning status, growth, and the time difference between hair growth and sample collection. Hair [THg] was moderately to strongly predictive of current blood [THg] for adult female Steller sea lions (Eumetopias jubatus), adult female California sea lions (Zalophus californianus), and adult harbor seals (Phoca vitulina), whereas hair [THg] was poorly predictive or not predictive (different times of year) of blood [THg] for adult northern elephant seals (Mirounga angustirostris). Within species, except for very young pups, hair [THg] was a weaker predictor of blood [THg] for prereproductive animals than for adults likely due to growth, variability in foraging behavior, and transitions between ontogenetic phases. Our results indicate that the relationship between hair [THg] and blood [THg] in pinnipeds is variable and that ontogenetic phase and life history should be considered when interpreting [THg] in these tissues.

  15. Naturalistic drive cycle synthesis for pickup trucks.

    Science.gov (United States)

    Liu, Zifan; Ivanco, Andrej; Filipi, Zoran

    2015-09-01

    Future pick-up trucks are meeting much stricter fuel economy and exhaust emission standards. Design tradeoffs will have to be carefully evaluated to satisfy consumer expectations within the regulatory and cost constraints. Boundary conditions will obviously be critical for decision making: thus, the understanding of how customers are driving in naturalistic settings is indispensable. Federal driving schedules, while critical for certification, do not capture the richness of naturalistic cycles, particularly the aggressive maneuvers that often shape consumer perception of performance. While there are databases with large number of drive cycles, applying all of them directly in the design process is impractical. Therefore, representative drive cycles that capture the essence of the naturalistic driving should be synthesized from naturalistic driving data. Naturalistic drive cycles are firstly categorized by investigating their micro-trip components, defined as driving activities between successive stops. Micro-trips are expected to characterize underlying local traffic conditions, and separate different driving patterns. Next, the transitions from one vehicle state to another vehicle state in each cycle category are captured with Transition Probability Matrix (TPM). Candidate drive cycles can subsequently be synthesized using Markov Chain based on TPMs for each category. Finally, representative synthetic drive cycles are selected through assessment of significant cycle metrics to identify the ones with smallest errors. This paper provides a framework for synthesis of representative drive cycles from naturalistic driving data, which can subsequently be used for efficient optimization of design or control of pick-up truck powertrains. Manufacturers will benefit from representative drive cycles in several aspects, including quick assessments of vehicle performance and energy consumption in simulations, component sizing and design, optimization of control strategies, and

  16. Distractions N' Driving: video game simulation educates young drivers on the dangers of texting while driving.

    Science.gov (United States)

    Saqer, Haneen; de Visser, Ewart; Strohl, Jonathan; Parasuraman, Raja

    2012-01-01

    The proliferation of portable communication and entertainment devices has introduced new dangers to the driving environment, particularly for young and inexperienced drivers. Graduate students from George Mason University illustrate a powerful, practical, and cost-effective program that has been successful in educating these drivers on the dangers of texting while driving, which can easily be adapted and implemented in other communities.

  17. Regime shift by an exotic nitrogen-fixing shrub mediates plant facilitation in primary succession.

    Directory of Open Access Journals (Sweden)

    Adriano Stinca

    Full Text Available Ecosystem invasion by non-native, nitrogen-fixing species is a global phenomenon with serious ecological consequences. However, in the Mediterranean basin few studies addressed the impact of invasion by nitrogen-fixing shrubs on soil quality and hydrological properties at local scale, and the possible effects on succession dynamics and ecosystem invasibility by further species. In this multidisciplinary study we investigated the impact of Genista aetnensis (Biv. DC., an exotic nitrogen-fixing shrub, on the Vesuvius Grand Cone (Southern Italy. Specifically, we tested the hypotheses that the invasion of G. aetnensis has a significant impact on soil quality, soil hydrological regime, local microclimate and plant community structure, and that its impact increases during the plant ontogenetic cycle. We showed that G. aetnensis, in a relatively short time-span (i.e. ~ 40 years, has been able to build-up an island of fertility under its canopy, by accumulating considerable stocks of C, N, and P in the soil, and by also improving the soil hydrological properties. Moreover, G. aetnensis mitigates the daily range of soil temperature, reducing the exposure of coexisting plants to extremely high temperatures and water loss by soil evaporation, particularly during the growing season. Such amelioration of soil quality, coupled with the mitigation of below-canopy microclimatic conditions, has enhanced plant colonization of the barren Grand Cone slopes, by both herbaceous and woody species. These results suggest that the invasion of G. aetnensis could eventually drive to the spread of other, more resource-demanding exotic species, promoting alternative successional trajectories that may dramatically affect the local landscape. Our study is the first record of the invasion of G. aetnensis, an additional example of the regime shifts driven by N-fixing shrubs in Mediterranean region. Further studies are needed to identity specific management practices that can

  18. Ontogenetic patterns in bluefish (Pomatomus saltatrix) feeding ecology and the effect on mercury biomagnification.

    Science.gov (United States)

    Szczebak, Joseph T; Taylor, David L

    2011-06-01

    In this study, bluefish (Pomatomus saltatrix; age 0-7, n = 632) and their prey (forage fish, macroinvertebrates, zooplankton; n = 2,005) were collected from the Narragansett Bay estuary (RI, USA), and total Hg concentration was measured in white muscle and whole-body tissues, respectively. Bluefish Hg concentrations were analyzed relative to fish length, prey Hg content, and ontogenetic shifts in habitat use and foraging ecology, the latter assessed using stomach content analysis (n = 711) and stable nitrogen (δ(15)N) and carbon (δ(13)C) isotope measurements (n = 360). Diet and δ(13)C analysis showed that age 0 bluefish consumed both benthic and pelagic prey (silversides, sand shrimp, planktonic crustaceans; δ(13)C = - 16.52‰), whereas age 1 + bluefish fed almost exclusively on pelagic forage fish (Atlantic menhaden, herring; δ(13)C = - 17.33‰). Bluefish total Hg concentrations were significantly correlated with length (mean Hg = 0.041 and 0.254 ppm wet wt for age 0 and age 1 + bluefish, respectively). Furthermore, Hg biomagnification rates were maximal during bluefish early life stages and decelerated over time, resulting in relatively high Hg concentrations in age 0 fish. Rapid Hg accumulation in age 0 bluefish is attributed to these individuals occupying a comparable trophic level to age 1 + bluefish (δ(15)N = 15.58 and 16.09‰; trophic level = 3.55 and 3.71 for age 0 and age 1 + bluefish, respectively), as well as juveniles having greater standardized consumption rates of Hg-contaminated prey. Finally, bluefish larger than 30 cm total length consistently had Hg levels above the U.S. Environmental Protection Agency criterion of 0.3 ppm. As such, frequent consumption of bluefish could pose a human health risk, and preferentially consuming smaller bluefish may be an inadequate strategy for minimizing human dietary exposure to Hg. Copyright © 2011 SETAC.

  19. Biometrie sexual and ontogenetic dimorphism on the marine catfish Genidens genidens (Siluriformes, Ariidae in a tropical estuary

    Directory of Open Access Journals (Sweden)

    Larissa G Paiva

    2015-11-01

    Full Text Available This paper aims to study the ontogenetic sexual dimorphism of Genidens genidens in Guanabara Bay, southeastern coast of Brazil. Altogether 378 specimens were anayzed (233 females and 145 males with total length ranging from 13.3 to 43.5 cm. Specimens were measured for 12 body measurements, sex was identified and maturity stages were recorded and classified. Pearson's linear correlation reveled a significant positive correlation between total length and all other body measures, except for base adipose fin, mouth depth and eye depth for immature females. Analyses nested PERMANOVA desing showed significant differences between maturity stages for each sex, between sexes considering or not maturity stages, indicating a variation in morphometric characteristics driven by sexual dimorphism. Differences among all maturity stages were also found, indicating an ontogenetic morphological difference. But immature individuals didn't differ between sexes indicating that differentiation patterns starts with sexual development. The most important measures differing males and females were related to head characteristics, which appears to be key parameters to evaluate sexual differences. Due to male incubation of fertilized eggs and juvenile individuals <59 mm in their oral cavity, head measures are proposed to be sex dimorphism not related to reproduction, but with post reproductive fase due to ecological and biological needs.

  20. Intersexual allometry differences and ontogenetic shifts of coloration patterns in two aquatic turtles, Graptemys oculifera and Graptemys flavimaculata

    Science.gov (United States)

    Ennen, Joshua R.; Lindeman, Peter V.; Lovich, Jeffrey E.

    2015-01-01

    Coloration can play critical roles in a species' biology. The allometry of color patterns may be useful for elucidating the evolutionary mechanisms responsible for shaping the traits. We measured characteristics relating to eight aspects of color patterns from Graptemys oculifera and G. flavimaculata to investigate the allometric differences among male, female, and unsexed juvenile specimens. Additionally, we investigated ontogenetic shifts by incorporating the unsexed juveniles into the male and female datasets. In general, male color traits were isometric (i.e., color scaled with body size), while females and juvenile color traits were hypoallometric, growing in size more slowly than the increase in body size. When we included unsexed juveniles in our male and female datasets, our linear regression analyses found all relationships to be hypoallometric and our model selection analysis found support for nonlinear models describing the relationship between body size and color patterns, suggestive of an ontogenetic shift in coloration traits for both sexes at maturity. Although color is critical for many species' biology and therefore under strong selective pressure in many other species, our results are likely explained by an epiphenomenon related to the different selection pressures on body size and growth rates between juveniles and adults and less attributable to the evolution of color patterns themselves.

  1. Ontogenetic changes in skeletal muscle fiber type, fiber diameter and myoglobin concentration in the Northern elephant seal (Mirounga angustirostris

    Directory of Open Access Journals (Sweden)

    Colby eMoore

    2014-06-01

    Full Text Available Northern elephant seals (Mirounga angustirostris (NES are known to be deep, long-duration divers and to sustain long-repeated patterns of breath-hold, or apnea. Some phocid dives remain within the bounds of aerobic metabolism, accompanied by physiological responses inducing lung compression, bradycardia and peripheral vasoconstriction. Current data suggest an absence of type IIb fibers in pinniped locomotory musculature. To date, no fiber type data exist for NES, a consummate deep diver. In this study, NES were biopsied in the wild. Ontogenetic changes in skeletal muscle were revealed through succinate dehydrogenase (SDH based fiber typing. Results indicated a predominance of uniformly shaped, large type I fibers and elevated myoglobin (Mb concentrations in the longissimus dorsi (LD muscle of adults. No type II muscle fibers were detected in any adult sampled. This was in contrast to the juvenile animals that demonstrated type II myosin in Western Blot analysis, indicative of an ontogenetic change in skeletal muscle with maturation. These data support previous hypotheses that the absence of type II fibers indicates reliance on aerobic metabolism during dives, as well as a depressed metabolic rate and low energy locomotion. We also suggest that the lack of type IIb fibers (adults may provide a protection against ischemia reperfusion (IR injury in vasoconstricted peripheral skeletal muscle.

  2. Extensive geographic and ontogenetic variation characterizes the trophic ecology of a temperate reef fish on southern California (USA) rocky reefs

    Science.gov (United States)

    Hamilton, Scott L.; Caselle, Jennifer E.; Lantz, Coulson A.; Egloff, Tiana L.; Kondo, Emi; Newsome, Seth D.; Loke-Smith, Kerri; Pondella, Daniel J.; Young, Kelly A.; Lowe, Christopher G.

    2015-01-01

    Interactions between predator and prey act to shape the structure of ecological communities, and these interactions can differ across space. California sheephead Semicossyphus pulcher are common predators of benthic invertebrates in kelp beds and rocky reefs in southern California, USA. Through gut content and stable isotope (δ13C and †15N) analyses, we investigated geographic and ontogenetic variation in trophic ecology across 9 populations located at island and mainland sites throughout southern California. We found extensive geographic variation in California sheephead diet composition over small spatial scales. Populations differed in the proportion of sessile filter/suspension feeders or mobile invertebrates in the diet. Spatial variation in diet was highly correlated with other life history and demographic traits (e.g. growth, survivorship, reproductive condition, and energy storage), in addition to proxies of prey availability from community surveys. Multivariate descriptions of the diet from gut contents roughly agreed with the spatial groupings of sites based on stable isotope analysis of both California sheephead and their prey. Ontogenetic changes in diet occurred consistently across populations, despite spatial differences in size structure. As California sheephead increase in size, diets shift from small filter feeders, like bivalves, to larger mobile invertebrates, such as sea urchins. Our results indicate that locations with large California sheephead present, such as many marine reserves, may experience increased predation pressure on sea urchins, which could ultimately affect kelp persistence. PMID:26246648

  3. Electric Vehicle - Economical driving

    DEFF Research Database (Denmark)

    Jensen, VCE, Steen V.; Schøn, Henriette

    1999-01-01

    Instruct the reader in getting most satisfaction out of an EV, especially concerning driving and loading.......Instruct the reader in getting most satisfaction out of an EV, especially concerning driving and loading....

  4. Dementia and driving

    Science.gov (United States)

    ... this page: //medlineplus.gov/ency/patientinstructions/000028.htm Dementia and driving To use the sharing features on ... please enable JavaScript. If your loved one has dementia , deciding when they can no longer drive may ...

  5. Profile of success

    DEFF Research Database (Denmark)

    Dahlgaard, Jens Jørn; Nørgaard, Anders; Jakobsen, Søren

    1998-01-01

    What management skills must Europe's business leaders improve to achieve business excellence? Which country's leaders are best placed for success? Does the next generation have what it takes to compete? In the second half of their study of the leadership styles that drive business excellence, Jens...... Dahlgaard, Anders Nørgaard and Søren Jakobsen describe an excellent leadership profile that provides the answers....

  6. Gear bearing drive

    Science.gov (United States)

    Mavroidis, Constantinos (Inventor); Vranish, John M. (Inventor); Weinberg, Brian (Inventor)

    2011-01-01

    A gear bearing drive provides a compact mechanism that operates as an actuator providing torque and as a joint providing support. The drive includes a gear arrangement integrating an external rotor DC motor within a sun gear. Locking surfaces maintain the components of the drive in alignment and provide support for axial loads and moments. The gear bearing drive has a variety of applications, including as a joint in robotic arms and prosthetic limbs.

  7. 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.

  8. Driving After a Stroke

    Science.gov (United States)

    ... 23,2015 Can I drive after a stroke? Driving is often a major concern after someone has a stroke. It’s not unusual for stroke survivors to want to drive. Being able to get around after a stroke is important. Safety behind the wheel is even more important after ...

  9. 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…

  10. Simple Driving Techniques

    DEFF Research Database (Denmark)

    Rosendahl, Mads

    2002-01-01

    -like language. Our aim is to extract a simple notion of driving and show that even in this tamed form it has much of the power of more general notions of driving. Our driving technique may be used to simplify functional programs which use function composition and will often be able to remove intermediate data...

  11. Synergy in RF Current Drive

    International Nuclear Information System (INIS)

    Dumont, R.J.; Giruzzi, G.

    2005-01-01

    Auxiliary methods for efficient non-inductive current drive in tokamaks generally involve the interaction of externally driven waves with superthermal electrons. Among the possible schemes, Lower Hybrid (LH) and Electron Cyclotron (EC) current drive have been so far the most successful. An interesting aspect of their combined use is the fact that since they involve possibly overlapping domains in velocity and configuration spaces, a synergy between them is expected for appropriate parameters. The signature of this effect, significant improvement of the EC current drive efficiency, results from a favorable interplay of the quasilinear diffusions induced by both waves. Recently, improvements of the EC current drive efficiency in the range of 2-4 have been measured in fully non-inductive discharges in the Tore Supra tokamak, providing the first clear evidence of this effect in steady-state conditions. We present here the experimental aspects of these discharges. The associated kinetic modeling and current state of understanding of the LH-EC synergy phenomenon are also discussed. (authors)

  12. Synergy in RF Current Drive

    International Nuclear Information System (INIS)

    Dumont, R.J.; Giruzzi, G.

    2005-01-01

    Auxiliary methods for efficient non-inductive current drive in tokamaks generally involve the interaction of externally driven waves with superthermal electrons. Among the possible schemes, Lower Hybrid (LH) and Electron Cyclotron (EC) current drive have been so far the most successful. An interesting aspect of their combined use is the fact that since they involve possibly overlapping domains in velocity and configuration spaces, a synergy between them is expected for appropriate parameters. The signature of this effect, significant improvement of the EC current drive efficiency, results from a favorable interplay of the quasilinear diffusions induced by both waves. Recently, improvements of the EC current drive efficiency in the range of 2-4 have been measured in fully non-inductive discharges in the Tore Supra tokamak, providing the first clear evidence of this effect in steady-state conditions. We present here the experimental aspects of these discharges. The associated kinetic modeling and current state of understanding of the LH-EC synergy phenomenon are also discussed

  13. Ontogenetic and intraspecific variation in the late Emsian - Eifelian (Devonian) conodonts Polygnathus serotinus and P. bultyncki in the Prague Basin (Czech Republic) and Nevada (western U.S.)

    Science.gov (United States)

    Klapper, Gilbert; Vodrážková, Stanislava

    2013-06-01

    Klapper, G. and Vodražkova, S. 2013. Ontogenetic and intraspecific variation in the late Emsian - Eifelian (Devonian) conodonts Polygnathus serotinus and P. bultyncki in the Prague Basin (Czech Republic) and Nevada (western U.S.). Acta Geologica Polonica, 63 (2), 153-174, Warszawa. Samples from populations of Polygnathus serotinus Telford 1975 and P. bultyncki Weddige 1977 from the Prague Basin and Nevada display normal variation for Devonian conodont species. A considerable number of previous authors, however, have proposed unnecessary synonyms of these two species, primarily because they have not recognized ontogenetic variation. In contrast, we interpret the variation as ontogenetic as well as intraspecific and present detailed synonymies as a result. A third species, P. praetrigonicus Bardashev 1992, which has been carried in open nomenclature for many years, is an important indicator of the basal costatus Zone in the Prague Basin, New York, and Nevada. We review the stratigraphic distribution of these three species and the conodont zonation across the Emsian-Eifelian (Lower-Middle Devonian) boundary. Polygnathus pseudocostatus sp. nov. (partitus-costatus zones, central Nevada) is described herein. We have observed a decrease in the pit size during ontogeny in P. bultyncki although we have not measured enough specimens to rule out intraspecific versus ontogenetic variation.

  14. Control rod drive

    International Nuclear Information System (INIS)

    Okutani, Tetsuro.

    1988-01-01

    Purpose: To provide a simple and economical control rod drive using a control circuit requiring no pulse circuit. Constitution: Control rods in a BWR type reactor are driven by hydraulic pressure and inserted or withdrawn in the direction of applying the hydraulic pressure. The direction of the hydraulic pressure is controlled by a direction control valve. Since the driving for the control rod is extremely important in view of the operation, a self diagnosis function is disposed for rapid inspection of possible abnormality. In the present invention, two driving contacts are disposed each by one between the both ends of a solenoid valve of the direction control valve for driving the control rod and the driving power source, and diagnosis is conducted by alternately operating them. Therefore, since it is only necessary that the control circuit issues a driving instruction only to one of the two driving contacts, the pulse circuit is no more required. Further, since the control rod driving is conducted upon alignment of the two driving instructions, the reliability of the control rod drive can be improved. (Horiuchi, T.)

  15. 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.

  16. Setting the reference for the use of Chironomus sancticaroli (Diptera: Chironomidae as bioindicator: Ontogenetic pattern of larval head structures

    Directory of Open Access Journals (Sweden)

    Débora Rebechi

    2012-04-01

    Full Text Available Species of Chironomidae are widely used as bioindicators of water quality, since their larvae undergo morphological deformities when in contact with sediment contaminated with chemicals. In this work we endeavored to study the morphology of head structures (antennae, mandible, mentum, pecten epipharyngis, ventromental plate and premandible throughout the development of the four larval instars of Chironomus sancticaroli Strixino & Strixino, 1981, which can be used in environmental impact analyses. Our results show that it is possible to differentiate among larval instars by doing a quantitative analysis on the number of striae on the ventromental plates. The six structures analyzed changed during larval ontogeny. These changes are part of the ontogeny of the immature stages not exposed to xenobiotics. We believe that the morphological pattern defined in this work can be used for comparisons with ontogenetic changes observed in field studies conducted in polluted environments.

  17. Ontogenetic body-mass scaling of nitrogen excretion relates to body surface area in diverse pelagic invertebrates

    DEFF Research Database (Denmark)

    Hirst, Andrew G.; Lilley, M.K.S.; Glazier, D.S.

    2017-01-01

    . Among diverse pelagic invertebrates that change shape during ontogeny, recent analysis has demonstrated a significant positive correlation between the body-mass allometry of respiration rates (measured as the ontogenetic body mass-scaling exponent bR) and the allometry of body surface area (b......A, as predicted from body-shape changes using a Euclidean model). As many pelagic invertebrates use a large portion of their external body surface for both resource uptake and waste excretion, we predicted that body-mass scaling exponents for rates of excretion of soluble N (bN) should also then relate...... to the degree of body-shape change during growth. We tested this hypothesis using literature data on bN for 39 species of pelagic invertebrates across five different phyla, and find strong support: bN is significantly positively correlated with predicted bA, whilst also co-varying with bR. Intraspecific...

  18. Superluminal warp drive

    Energy Technology Data Exchange (ETDEWEB)

    Gonzalez-Diaz, Pedro F. [Colina de los Chopos, Centro de Fisica ' Miguel A. Catalan' , Instituto de Matematicas y Fisica Fundamental, Consejo Superior de Investigaciones Cientificas, Serrano 121, 28006 Madrid (Spain)], E-mail: p.gonzalezdiaz@imaff.cfmac.csic.es

    2007-09-20

    In this Letter we consider a warp drive spacetime resulting from that suggested by Alcubierre when the spaceship can only travel faster than light. Restricting to the two dimensions that retains most of the physics, we derive the thermodynamic properties of the warp drive and show that the temperature of the spaceship rises up as its apparent velocity increases. We also find that the warp drive spacetime can be exhibited in a manifestly cosmological form.

  19. Individual variation in ontogenetic niche shifts in habitat use and movement patterns of a large estuarine predator (Carcharhinus leucas).

    Science.gov (United States)

    Matich, Philip; Heithaus, Michael R

    2015-06-01

    Ontogenetic niche shifts are common among animals, yet most studies only investigate niche shifts at the population level, which may overlook considerable differences among individuals in the timing and dynamics of these shifts. Such divergent behaviors within size-/age-classes have important implications for the roles a population-and specific age-classes-play in their respective ecosystem(s). Using acoustic telemetry, we tracked the movements of juvenile bull sharks in the Shark River Estuary of Everglades National Park, Florida, and found that sharks increased their use of marine microhabitats with age to take advantage of more abundant resources, but continued to use freshwater and estuarine microhabitats as refuges from marine predators. Within this population-level ontogenetic niche shift, however, movement patterns varied among individual sharks, with 47 % of sharks exhibiting condition-dependent habitat use and 53 % appearing risk-averse regardless of body condition. Among sharks older than age 0, fifty percent made regular movements between adjacent regions of the estuary, while the other half made less predictable movements that often featured long-term residence in specific regions. Individual differences were apparently shaped by both intrinsic and extrinsic factors, including individual responses to food-risk trade-offs and body condition. These differences appear to develop early in the lives of bull sharks, and persist throughout their residencies in nursery habitats. The widespread occurrence of intraspecific variation in behavior among mobile taxa suggests it is important in shaping population dynamics of at least some species, and elucidating the contexts and timing in which it develops and persists is important for understanding its role within communities.

  20. Ontogenetic and among-individual variation in foraging strategies of northeast Pacific white sharks based on stable isotope analysis.

    Science.gov (United States)

    Kim, Sora L; Tinker, M Tim; Estes, James A; Koch, Paul L

    2012-01-01

    There is growing evidence for individuality in dietary preferences and foraging behaviors within populations of various species. This is especially important for apex predators, since they can potentially have wide dietary niches and a large impact on trophic dynamics within ecosystems. We evaluate the diet of an apex predator, the white shark (Carcharodon carcharias), by measuring the stable carbon and nitrogen isotope composition of vertebral growth bands to create lifetime records for 15 individuals from California. Isotopic variations in white shark diets can reflect within-region differences among prey (most importantly related to trophic level), as well as differences in baseline values among the regions in which sharks forage, and both prey and habitat preferences may shift with age. The magnitude of isotopic variation among sharks in our study (>5‰ for both elements) is too great to be explained solely by geographic differences, and so must reflect differences in prey choice that may vary with sex, size, age and location. Ontogenetic patterns in δ(15)N values vary considerably among individuals, and one third of the population fit each of these descriptions: 1) δ(15)N values increased throughout life, 2) δ(15)N values increased to a plateau at ∼5 years of age, and 3) δ(15)N values remained roughly constant values throughout life. Isotopic data for the population span more than one trophic level, and we offer a qualitative evaluation of diet using shark-specific collagen discrimination factors estimated from a 3+ year captive feeding experiment (Δ(13)C(shark-diet) and Δ(15)N(shark-diet) equal 4.2‰ and 2.5‰, respectively). We assess the degree of individuality with a proportional similarity index that distinguishes specialists and generalists. The isotopic variance is partitioned among differences between-individual (48%), within-individuals (40%), and by calendar year of sub-adulthood (12%). Our data reveal substantial ontogenetic and

  1. Growth trajectories in the cave bear and its extant relatives: an examination of ontogenetic patterns in phylogeny.

    Science.gov (United States)

    Fuchs, Manuela; Geiger, Madeleine; Stange, Madlen; Sánchez-Villagra, Marcelo R

    2015-11-02

    The study of postnatal ontogeny can provide insights into evolution by offering an understanding of how growth trajectories have evolved resulting in adult morphological disparity. The Ursus lineage is a good subject for studying cranial and mandibular shape and size variation in relation to postnatal ontogeny and phylogeny because it is at the same time not diverse but the species exhibit different feeding ecologies. Cranial and mandibular shapes of Ursus arctos (brown bear), U. maritimus (polar bear), U. americanus (American black bear), and the extinct U. spelaeus (cave bear) were examined, using a three-dimensional geometric morphometric approach. Additionally, ontogenetic series of crania and mandibles of U. arctos and U. spelaeus ranging from newborns to senile age were sampled. The distribution of specimens in morphospace allowed to distinguish species and age classes and the ontogenetic trajectories U. arctos and U. spelaeus were found to be more similar than expected by chance. Cranial shape changes during ontogeny are largely size related whereas the evolution of cranial shape disparity in this clade appears to be more influenced by dietary adaptation than by size and phylogeny. The different feeding ecologies are reflected in different cranial and mandibular shapes among species. The cranial and mandibular shape disparity in the Ursus lineage appears to be more influenced by adaptation to diet than by size or phylogeny. In contrast, the cranial and mandibular shape changes during postnatal ontogeny in U. arctos and U. spelaeus are probably largely size related. The patterns of morphospace occupation of the cranium and the mandible in adults and through ontogeny are different.

  2. Ontogenetic and among-individual variation in foraging strategies of northeast Pacific white sharks based on stable isotope analysis

    Science.gov (United States)

    Kim, S.L.; Tinker, M. Tim; Estes, J.A.; Koch, P.L.

    2012-01-01

    There is growing evidence for individuality in dietary preferences and foraging behaviors within populations of various species. This is especially important for apex predators, since they can potentially have wide dietary niches and a large impact on trophic dynamics within ecosystems. We evaluate the diet of an apex predator, the white shark (Carcharodon carcharias), by measuring the stable carbon and nitrogen isotope composition of vertebral growth bands to create lifetime records for 15 individuals from California. Isotopic variations in white shark diets can reflect within-region differences among prey (most importantly related to trophic level), as well as differences in baseline values among the regions in which sharks forage, and both prey and habitat preferences may shift with age. The magnitude of isotopic variation among sharks in our study (>5‰ for both elements) is too great to be explained solely by geographic differences, and so must reflect differences in prey choice that may vary with sex, size, age and location. Ontogenetic patterns in δ15N values vary considerably among individuals, and one third of the population fit each of these descriptions: 1) δ15N values increased throughout life, 2) δ15N values increased to a plateau at ~5 years of age, and 3) δ15N values remained roughly constant values throughout life. Isotopic data for the population span more than one trophic level, and we offer a qualitative evaluation of diet using shark-specific collagen discrimination factors estimated from a 3+ year captive feeding experiment (Δ13Cshark-diet and Δ15Nshark-diet equal 4.2‰ and 2.5‰, respectively). We assess the degree of individuality with a proportional similarity index that distinguishes specialists and generalists. The isotopic variance is partitioned among differences between-individual (48%), within-individuals (40%), and by calendar year of sub-adulthood (12%). Our data reveal substantial ontogenetic and individual dietary

  3. Ontogenetic and among-individual variation in foraging strategies of northeast Pacific white sharks based on stable isotope analysis.

    Directory of Open Access Journals (Sweden)

    Sora L Kim

    Full Text Available There is growing evidence for individuality in dietary preferences and foraging behaviors within populations of various species. This is especially important for apex predators, since they can potentially have wide dietary niches and a large impact on trophic dynamics within ecosystems. We evaluate the diet of an apex predator, the white shark (Carcharodon carcharias, by measuring the stable carbon and nitrogen isotope composition of vertebral growth bands to create lifetime records for 15 individuals from California. Isotopic variations in white shark diets can reflect within-region differences among prey (most importantly related to trophic level, as well as differences in baseline values among the regions in which sharks forage, and both prey and habitat preferences may shift with age. The magnitude of isotopic variation among sharks in our study (>5‰ for both elements is too great to be explained solely by geographic differences, and so must reflect differences in prey choice that may vary with sex, size, age and location. Ontogenetic patterns in δ(15N values vary considerably among individuals, and one third of the population fit each of these descriptions: 1 δ(15N values increased throughout life, 2 δ(15N values increased to a plateau at ∼5 years of age, and 3 δ(15N values remained roughly constant values throughout life. Isotopic data for the population span more than one trophic level, and we offer a qualitative evaluation of diet using shark-specific collagen discrimination factors estimated from a 3+ year captive feeding experiment (Δ(13C(shark-diet and Δ(15N(shark-diet equal 4.2‰ and 2.5‰, respectively. We assess the degree of individuality with a proportional similarity index that distinguishes specialists and generalists. The isotopic variance is partitioned among differences between-individual (48%, within-individuals (40%, and by calendar year of sub-adulthood (12%. Our data reveal substantial ontogenetic and

  4. 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.

  5. Universal Drive Train Facility

    Data.gov (United States)

    Federal Laboratory Consortium — This vehicle drive train research facility is capable of evaluating helicopter and ground vehicle power transmission technologies in a system level environment. The...

  6. Piezoelectric drive circuit

    Science.gov (United States)

    Treu, C.A. Jr.

    1999-08-31

    A piezoelectric motor drive circuit is provided which utilizes the piezoelectric elements as oscillators and a Meacham half-bridge approach to develop feedback from the motor ground circuit to produce a signal to drive amplifiers to power the motor. The circuit automatically compensates for shifts in harmonic frequency of the piezoelectric elements due to pressure and temperature changes. 7 figs.

  7. Wrong-way driving.

    NARCIS (Netherlands)

    2006-01-01

    Wrong-way driving is a phenomenon that mainly happens on motorways. Although the number of wrong-way crashes is relatively limited, their consequences are much more severe than the consequences of other motorway injury crashes. The groups most often causing wrong-way driving accidents are young,

  8. Recognizing driving in haste

    NARCIS (Netherlands)

    Rendón-Vélez, E.

    2014-01-01

    One can often hear people discussing the reasons why a road accident has happened: “She had to pick up her kids in the school before four o’clock and she was driving in haste and careless”, “He was stressed, he wanted to reach the beginning of the football match, tried to drive faster and didn't

  9. Control rod drives

    International Nuclear Information System (INIS)

    Futatsugi, Masao.

    1980-01-01

    Purpose: To secure the reactor operation safety by the provision of a fluid pressure detecting section for control rod driving fluid and a control rod interlock at the midway of the flow pass for supplying driving fluid to the control rod drives. Constitution: Between a driving line and a direction control valve are provided a pressure detecting portion, an alarm generating device, and a control rod inhibition interlock. The driving fluid from a driving fluid source is discharged by way of a pump and a manual valve into the reactor in which the control rods and reactor fuels are contained. In addition, when the direction control valve is switched and the control rods are inserted and extracted by the control rod drives, the pressure in the driving line is always detected by the pressure detection section, whereby if abnormal pressure is resulted, the alarm generating device is actuated to warn the abnormality and the control rod inhibition interlock is actuated to lock the direction control valve thereby secure the safety operation of the reactor. (Seki, T.)

  10. Switched reluctance motor drives

    Indian Academy of Sciences (India)

    Davis RM, Ray WF, Blake RJ 1981 Inverter drive for switched reluctance: circuits and component ratings. Inst. Elec. Eng. Proc. B128: 126-136. Ehsani M. 1991 Position Sensor elimination technique for the switched reluctance motor drive. US Patent No. 5,072,166. Ehsani M, Ramani K R 1993 Direct control strategies based ...

  11. Self-driving carsickness

    NARCIS (Netherlands)

    Diels, C.; Bos, J.E.

    2016-01-01

    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

  12. Self-driving carsickness.

    NARCIS (Netherlands)

    Diels, C.; Bos, J.E.

    2016-01-01

    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

  13. Fundamentals of electrical drives

    CERN Document Server

    Veltman, André; De Doncker, Rik W

    2007-01-01

    Provides a comprehensive introduction to various aspects of electrical drive systems. This volume provides a presentation of dynamic generic models that cover all major electrical machine types and modulation/control components of a drive as well as dynamic and steady state analysis of transformers and electrical machines.

  14. Electric Vehicle - Economical driving

    DEFF Research Database (Denmark)

    Jensen, VCE, Steen V.; Schøn, Henriette

    1999-01-01

    How do you reduce the energy-wast when driving and loading EV's - or rather: How do I get more km/l out of an EV......How do you reduce the energy-wast when driving and loading EV's - or rather: How do I get more km/l out of an EV...

  15. Driving the Landscape

    Science.gov (United States)

    Haff, P. K.

    2012-12-01

    Technological modification of the earth's surface (e.g., agriculture, urbanization) is an old story in human history, but what about the future? The future of landscape in an accelerating technological world, beyond a relatively short time horizon, lies hidden behind an impenetrable veil of complexity. Sufficiently complex dynamics generates not only the trajectory of a variable of interest (e.g., vegetation cover) but also the environment in which that variable evolves (e.g., background climate). There is no way to anticipate what variables will define that environment—the dynamics creates its own variables. We are always open to surprise by a change of conditions we thought or assumed were fixed or by the appearance of new phenomena of whose possible existence we had been unaware or thought unlikely. This is especially true under the influence of technology, where novelty is the rule. Lack of direct long-term predictability of landscape change does not, however, mean we cannot say anything about its future. The presence of persistence (finite time scales) in a system means that prediction by a calibrated numerical model should be good for a limited period of time barring bad luck or faulty implementation. Short-term prediction, despite its limitations, provides an option for dealing with the longer-term future. If a computer-controlled car tries to drive itself from New York to Los Angeles, no conceivable (or possible) stand-alone software can be constructed to predict a priori the space-time trajectory of the vehicle. Yet the drive is normally completed easily by most drivers. The trip is successfully completed because each in a series of very short (linear) steps can be "corrected" on the fly by the driver, who takes her cues from the environment to keep the car on the road and headed toward its destination. This metaphor differs in a fundamental way from the usual notion of predicting geomorphic change, because it involves a goal—to reach a desired

  16. Control rod drives

    International Nuclear Information System (INIS)

    Nakamura, Akira.

    1984-01-01

    Purpose: To enable to monitor the coupling state between a control rod and a control rod drive. Constitution: After the completion of a control rod withdrawal, a coolant pressure is applied to a control rod drive being adjusted so as to raise only the control rod drive and, in a case where the coupling between the control rod drive and the control rod is detached, the former is elevated till it contacts the control rod and then stopped. The actual stopping position is detected by an actual position detection circuit and compared with a predetermined position stored in a predetermined position detection circuit. If both of the positions are not aligned with each other, it is judged by a judging circuit that the control rod and the control rod drives are not combined. (Sekiya, K.)

  17. 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.

  18. Fast wave current drive

    International Nuclear Information System (INIS)

    Goree, J.; Ono, M.; Colestock, P.; Horton, R.; McNeill, D.; Park, H.

    1985-07-01

    Fast wave current drive is demonstrated in the Princeton ACT-I toroidal device. The fast Alfven wave, in the range of high ion-cyclotron harmonics, produced 40 A of current from 1 kW of rf power coupled into the plasma by fast wave loop antenna. This wave excites a steady current by damping on the energetic tail of the electron distribution function in the same way as lower-hybrid current drive, except that fast wave current drive is appropriate for higher plasma densities

  19. 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.

  20. Ontogenetic Tooth Reduction in Stenopterygius quadriscissus (Reptilia: Ichthyosauria: Negative Allometry, Changes in Growth Rate, and Early Senescence of the Dental Lamina.

    Directory of Open Access Journals (Sweden)

    Daniel G Dick

    Full Text Available We explore the functional, developmental, and evolutionary processes which are argued to produce tooth reduction in the extinct marine reptile Stenopterygius quadriscissus (Reptilia: Ichthyosauria. We analyze the relationship between mandible growth and tooth size, shape, and count, to establish an ontogenetic trend. The pattern in S. quadriscissus is consistent with hypotheses of tooth size reduction by neutral selection, and this unusual morphology (a functionally edentulous rostrum was produced by a series of different evolutionary developmental changes that are known for other taxa showing tooth reduction and loss. Specifically, this species evolved functional edentulism by evolutionary changes in the growth allometry of the dentition and by altering growth rates through ontogeny. This observation supports previous hypotheses that S. quadriscissus underwent ontogenetic tooth reduction. Tooth reduction in S. quadriscissus may be caused by unique selective pressures resulting from prey choice and feeding behavior, expanding our current understanding of the mechanisms producing tooth reduction.

  1. Ontogenetic development of attack behaviour by turbot larvae when exposed to copepod prey

    DEFF Research Database (Denmark)

    Højgaard, Jacob K.; Bruno, Eleonora; Støttrup, Josianne Gatt

    2018-01-01

    offered small nauplii (129–202 μm), large nauplii (222–278 μm) and copepodites (342–542 μm), of the calanoid copepod Acartia tonsa. At 8 DPH, turbot larvae had the highest capture success (67%) when offered small nauplii, with a lower capture success of large nauplii (27%) but totally lacked...... by the larva on the copepod was examined, and the approach pattern of the larva was identified as a controlling mechanism for their strike distance, with the initial approach speed of larva at DPH 10 being significantly less than at DPH 8. In all successful attacks, the strike distance was less than 1.17 mm...

  2. Ontogenetic study of the skull in modern humans and the common chimpanzees: neotenic hypothesis reconsidered with a tridimensional Procrustes analysis.

    Science.gov (United States)

    Penin, Xavier; Berge, Christine; Baylac, Michel

    2002-05-01

    Heterochronic studies compare ontogenetic trajectories of an organ in different species: here, the skulls of common chimpanzees and modern humans. A growth trajectory requires three parameters: size, shape, and ontogenetic age. One of the great advantages of the Procrustes method is the precise definition of size and shape for whole organs such as the skull. The estimated ontogenetic age (dental stages) is added to the plot to give a graphical representation to compare growth trajectories. We used the skulls of 41 Homo sapiens and 50 Pan troglodytes at various stages of growth. The Procrustes superimposition of all specimens was completed by statistical procedures (principal component analysis, multivariate regression, and discriminant function) to calculate separately size-related shape changes (allometry common to chimpanzees and humans), and interspecific shape differences (discriminant function). The results confirm the neotenic theory of the human skull (sensu Gould [1977] Ontogeny and Phylogeny, Cambridge: Harvard University Press; Alberch et al. [1979] Paleobiology 5:296-317), but modify it slightly. Human growth is clearly retarded in terms of both the magnitude of changes (size-shape covariation) and shape alone (size-shape dissociation) with respect to the chimpanzees. At the end of growth, the adult skull in humans reaches an allometric shape (size-related shape) which is equivalent to that of juvenile chimpanzees with no permanent teeth, and a size which is equivalent to that of adult chimpanzees. Our results show that human neoteny involves not only shape retardation (paedomorphosis), but also changes in relative growth velocity. Before the eruption of the first molar, human growth is accelerated, and then strongly decelerated, relative to the growth of the chimpanzee as a reference. This entails a complex process, which explains why these species reach the same overall (i.e., brain + face) size in adult stage. The neotenic traits seem to concern

  3. Ontogenetic Change in the Temporal Region of the Early Permian Parareptile Delorhynchus cifellii and the Implications for Closure of the Temporal Fenestra in Amniotes.

    Directory of Open Access Journals (Sweden)

    Yara Haridy

    Full Text Available A juvenile specimen of Delorhynchus cifellii, collected from the Early Permian fissure-fill deposits of Richards Spur, Oklahoma, permits the first detailed study of cranial ontogeny in this parareptile. The specimen, consisting of a partially articulated skull and mandible, exhibits several features that identify it as juvenile. The dermal tuberosities that ornament the dorsal side and lateral edges of the largest skull of D. cifellii specimens, are less prominent in the intermediate sized holotype, and are absent in the new specimen. This indicates that the new specimen represents an earlier ontogenetic stage than all previously described members of this species. In addition, the incomplete interdigitation of the sutures, most notably along the fronto-nasal contact, plus the proportionally larger sizes of the orbit and temporal fenestrae further support an early ontogenetic stage for this specimen. Comparisons between this juvenile and previously described specimens reveal that the size and shape of the temporal fenestra in Delorhynchus appear to vary through ontogeny, due to changes in the shape and size of the bordering cranial elements. The jugal of the juvenile specimen is tri-radiate and similar in outline with those found in other amniotes with temporal fenestrae. The available growth series of D. cifellii shows that the jugal gradually becomes a more robust, tetra-radiate element, as the proportionate size of the temporal fenestra is reduced. Ontogenetic changes of other elements that form the border of the fenestra also contribute to its reduction. This growth series provides valuable new information regarding the ontogenetic trajectory of the temporal fenestra in a Palaeozoic reptile, which may be applicable to the evolutionary event of loss of temporal fenestration in other amniotes.

  4. Linear step drive

    International Nuclear Information System (INIS)

    Haniger, L.; Elger, R.; Kocandrle, L.; Zdebor, J.

    1986-01-01

    A linear step drive is described developed in Czechoslovak-Soviet cooperation and intended for driving WWER-1000 control rods. The functional principle is explained of the motor and the mechanical and electrical parts of the drive, power control, and the indicator of position are described. The motor has latches situated in the reactor at a distance of 3 m from magnetic armatures, it has a low structural height above the reactor cover, which suggests its suitability for seismic localities. Its magnetic circuits use counterpoles; the mechanical shocks at the completion of each step are damped using special design features. The position indicator is of a special design and evaluates motor position within ±1% of total travel. A drive diagram and the flow chart of both the control electronics and the position indicator are presented. (author) 4 figs

  5. Fundamentals of electrical drives

    NARCIS (Netherlands)

    Veltman, A.; Pulle, D.W.J.; de Doncker, R.W.

    2016-01-01

    Comprehensive, user-friendly, color illustrated introductory text for electrical drive systems that simplifies the understanding of electrical machine principles Updated edition covers innovations in machine design, power semi-conductors, digital signal processors and simulation software Presents

  6. Science of driving.

    Science.gov (United States)

    2016-08-01

    The Science of Driving project focused on developing a collaborative relationship to develop curriculum units for middle school and high school students to engage them in exciting real-world scenarios. This effort involved faculty, staff, and student...

  7. Drugs and driving

    NARCIS (Netherlands)

    Walsh, J. Michael; De Gier, Johan J.; Christopherson, Asbjørg S.; Verstraete, Alain G.

    The authors present a global overview on the issue of drugs and driving covering four major areas: (1) Epidemiology and Prevalence-which reviews epidemiological research, summarizes available information, discusses the methodological shortcomings of extant studies, and makes recommendations for

  8. Ontogenetic changes in feeding and food preferences of the dog conch Laevistrombus canarium Linnaeus 1758 (Mollusca: Gastropoda) from Merambong shoal, Malaysia

    Science.gov (United States)

    Husna, Wan Nurul Wan Hassan; Mazlan, Abd Ghaffar; Cob, Zaidi Che

    2017-09-01

    Laevistrombus canarium is one of the marine gastropod mollusks that have high commercial value, particularly in the aquaculture sector in Malaysia. This study was conducted to determine the feeding and food items of L. canarium at different ontogenetic stages (juveniles, sub-adults and adults) from Merambong shoals, Malaysia. Field observations on feeding activity were conducted, followed by detailed laboratory analysis on the stomach content. Five-minutes observations on randomly selected individuals were conducted at the field sampling site and their feeding activities were recorded with reference to age stage. Various shell sizes from each ontogenetic stage were randomly collected and quickly anaesthetized with ice and preserved in 10% formalin before being transported to the laboratory for stomach content analyses. Field observations showed that L. canarium mainly grazed on epiphytes occurring on seagrass (46.67%), followed by sediment surface (40%) and epiphytes occurring on macroalgae (13.33%). Stomach content analyses showed a significant difference ( P 0.05) was detected between the three main food items (diatoms, sand particles and detritus) among the ontogenetic stages. Therefore, feeding activity revealed the role of the dog conch in the marine food network. While, classification of the types of food consumed by L. canarium through stomach content analysis determines the particular position of the gastropod in the food chain. Further studies are needed to provide a better insight between trophic relationships of L. canarium with marine ecosystem.

  9. Modulation by K+ Plus NH4+ of microsomal (Na+, K+)-ATPase activity in selected ontogenetic stages of the diadromous river shrimp Macrobrachium amazonicum (Decapoda, Palaemonidae).

    Science.gov (United States)

    Leone, Francisco A; Bezerra, Thais M S; Garçon, Daniela P; Lucena, Malson N; Pinto, Marcelo R; Fontes, Carlos F L; McNamara, John C

    2014-01-01

    We investigate the synergistic stimulation by K(+) plus NH4 (+) of (Na(+), K(+))-ATPase activity in microsomal preparations of whole zoea I and decapodid III, and in juvenile and adult river shrimp gills. Modulation of (Na(+), K(+))-ATPase activity is ontogenetic stage-specific, and particularly distinct between juveniles and adults. Although both gill enzymes exhibit two different sites for K(+) and NH4 (+) binding, in the juvenile enzyme, these two sites are equivalent: binding by both ions results in slightly stimulated activity compared to that of a single ionic species. In the adult enzyme, the sites are not equivalent: when one ion occupies its specific binding site, (Na(+), K(+))-ATPase activity is stimulated synergistically by ≈ 50% on binding of the complementary ion. Immunolocalization reveals the enzyme to be distributed predominantly throughout the intralamellar septum in the gill lamellae of juveniles and adults. Western blot analyses demonstrate a single immunoreactive band, suggesting a single (Na(+), K(+))-ATPase α-subunit isoform that is distributed into different density membrane fractions, independently of ontogenetic stage. We propose a model for the modulation by K(+) and NH4 (+) of gill (Na(+), K(+))-ATPase activity. These findings suggest that the gill enzyme may be regulated by NH4 (+) during ontogenetic development in M. amazonicum.

  10. Modulation by K+ Plus NH4+ of microsomal (Na+, K+-ATPase activity in selected ontogenetic stages of the diadromous river shrimp Macrobrachium amazonicum (Decapoda, Palaemonidae.

    Directory of Open Access Journals (Sweden)

    Francisco A Leone

    Full Text Available We investigate the synergistic stimulation by K(+ plus NH4 (+ of (Na(+, K(+-ATPase activity in microsomal preparations of whole zoea I and decapodid III, and in juvenile and adult river shrimp gills. Modulation of (Na(+, K(+-ATPase activity is ontogenetic stage-specific, and particularly distinct between juveniles and adults. Although both gill enzymes exhibit two different sites for K(+ and NH4 (+ binding, in the juvenile enzyme, these two sites are equivalent: binding by both ions results in slightly stimulated activity compared to that of a single ionic species. In the adult enzyme, the sites are not equivalent: when one ion occupies its specific binding site, (Na(+, K(+-ATPase activity is stimulated synergistically by ≈ 50% on binding of the complementary ion. Immunolocalization reveals the enzyme to be distributed predominantly throughout the intralamellar septum in the gill lamellae of juveniles and adults. Western blot analyses demonstrate a single immunoreactive band, suggesting a single (Na(+, K(+-ATPase α-subunit isoform that is distributed into different density membrane fractions, independently of ontogenetic stage. We propose a model for the modulation by K(+ and NH4 (+ of gill (Na(+, K(+-ATPase activity. These findings suggest that the gill enzyme may be regulated by NH4 (+ during ontogenetic development in M. amazonicum.

  11. Successful ageing

    DEFF Research Database (Denmark)

    Bülow, Morten Hillgaard; Söderqvist, Thomas

    2014-01-01

    Since the late 1980s, the concept of ‘ successful ageing’ has set the frame for discourse about contemporary ageing research. Through an analysis of the reception to John W. Rowe and Robert L. Kahn's launch of the concept of ‘ successful ageing’ in 1987, this article maps out the important themes...... and discussions that have emerged from the interdisciplinary field of ageing research. These include an emphasis on interdisciplinarity; the interaction between biology, psycho-social contexts and lifestyle choices; the experiences of elderly people; life-course perspectives; optimisation and prevention...... strategies; and the importance of individual, societal and scientific conceptualisations and understandings of ageing. By presenting an account of the recent historical uses, interpretations and critiques of the concept, the article unfolds the practical and normative complexities of ‘ successful ageing’....

  12. Citation Success

    DEFF Research Database (Denmark)

    Vaio, Gianfranco Di; Waldenström, Daniel; Weisdorf, Jacob Louis

    2012-01-01

    This study examines the determinants of citation success among authors who have recently published their work in economic history journals. Besides offering clues about how to improve one's scientific impact, our citation analysis also sheds light on the state of the field of economic history...... find similar patterns when assessing the same authors' citation success in economics journals. As a novel feature, we demonstrate that the diffusion of research — publication of working papers, as well as conference and workshop presentations — has a first-order positive impact on the citation rate........ Consistent with our expectations, we find that full professors, authors appointed at economics and history departments, and authors working in Anglo-Saxon and German countries are more likely to receive citations than other scholars. Long and co-authored articles are also a factor for citation success. We...

  13. Predation drives nesting success in moist highland grasslands: the ...

    African Journals Online (AJOL)

    By focusing on process-oriented data rather than inventory-type data, this study provides a robust understanding of the effects of agricultural management on grassland bird reproductive output in the moist highland grasslands (MHGs) of South Africa. Four-hundred and four nests of 12 grassland-breeding bird species were ...

  14. Key Elements of a Successful Drive toward Marketing Strategy Making

    Science.gov (United States)

    Cann, Cynthia W.; George, Marie A.

    2003-01-01

    A conceptual model is presented that depicts the relationship between an internal marketing function and an organization's readiness to learn. Learning and marketing orientations are identified as components to marketing strategy making. Key organizational functions, including communication and decision-making, are utilized in a framework for…

  15. Instant Google Drive starter

    CERN Document Server

    Procopio, Mike

    2013-01-01

    This book is a Starter which teaches you how to use Google Drive practically. This book is perfect for people of all skill levels who want to enjoy the benefits of using Google Drive to safely store their files online and in the cloud. It's also great for anyone looking to learn more about cloud computing in general. Readers are expected to have an Internet connection and basic knowledge of using the internet.

  16. Control rod driving mechanism

    International Nuclear Information System (INIS)

    Ooshima, Yoshio.

    1983-01-01

    Purpose: To perform reliable scram operation, even if abnormality should occur in a system instructing scram operation in FBR type reactors. Constitution: An aluminum alloy member to be melt at a predetermined temperature (about 600sup(o)C) is disposed to a connection part between a control rod and a driving mechanism, whereby the control rod is detached from the driving mechanism and gravitationally fallen to the reactor core. (Ikeda, J.)

  17. 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

  18. Belt drive construction improvement

    Directory of Open Access Journals (Sweden)

    I.Yu. Khomenko

    2012-08-01

    Full Text Available The possibility of the traction capacity increase of the belt drive TRK is examined. This was done for the purpose of air conditioning system of passenger car with double-generator system energy supplying. Belts XPC (made by the German firm «Continental ContiTech» testing were conducted. The results confirmed the possibility of their usage in order to improve belt drive TRK characteristics.

  19. 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.

  20. Dementia and driving.

    Science.gov (United States)

    O'Neill, D; Neubauer, K; Boyle, M; Gerrard, J; Surmon, D; Wilcock, G K

    1992-04-01

    Many European countries test cars, but not their drivers, as they age. There is evidence to suggest that human factors are more important than vehicular factors as causes of motor crashes. The elderly also are involved in more accidents per distance travelled than middle-aged drivers. As the UK relies on self-certification of health by drivers over the age of 70 years, we examined the driving practices of patients with dementia attending a Memory Clinic. Nearly one-fifth of 329 patients with documented dementia continued to drive after the onset of dementia, and impaired driving ability was noted in two-thirds of these. Their families experienced great difficulty in persuading patients to stop driving, and had to invoke outside help in many cases. Neuropsychological tests did not help to identify those who drove badly while activity of daily living scores were related to driving ability. These findings suggest that many patients with dementia drive in an unsafe fashion after the onset of the illness. The present system of self-certification of health by the elderly for driver-licensing purposes needs to be reassessed.

  1. Coastal Upwelling Drives Intertidal Assemblage Structure and Trophic Ecology.

    Science.gov (United States)

    Reddin, Carl J; Docmac, Felipe; O'Connor, Nessa E; Bothwell, John H; Harrod, Chris

    2015-01-01

    Similar environmental driving forces can produce similarity among geographically distant ecosystems. Coastal oceanic upwelling, for example, has been associated with elevated biomass and abundance patterns of certain functional groups, e.g., corticated macroalgae. In the upwelling system of Northern Chile, we examined measures of intertidal macrobenthic composition, structure and trophic ecology across eighteen shores varying in their proximity to two coastal upwelling centres, in a hierarchical sampling design (spatial scales of >1 and >10 km). The influence of coastal upwelling on intertidal communities was confirmed by the stable isotope values (δ13C and δ15N) of consumers, including a dominant suspension feeder, grazers, and their putative resources of POM, epilithic biofilm, and macroalgae. We highlight the utility of muscle δ15N from the suspension feeding mussel, Perumytilus purpuratus, as a proxy for upwelling, supported by satellite data and previous studies. Where possible, we used corrections for broader-scale trends, spatial autocorrelation, ontogenetic dietary shifts and spatial baseline isotopic variation prior to analysis. Our results showed macroalgal assemblage composition, and benthic consumer assemblage structure, varied significantly with the intertidal influence of coastal upwelling, especially contrasting bays and coastal headlands. Coastal topography also separated differences in consumer resource use. This suggested that coastal upwelling, itself driven by coastline topography, influences intertidal communities by advecting nearshore phytoplankton populations offshore and cooling coastal water temperatures. We recommend the isotopic values of benthic organisms, specifically long-lived suspension feeders, as in situ alternatives to offshore measurements of upwelling influence.

  2. Citation Success

    DEFF Research Database (Denmark)

    Di Vaio, Gianfranco; Waldenström, Daniel; Weisdorf, Jacob Louis

    affects citations. In regard to author-specific characteristics, male authors, full professors and authors working economics or history departments, and authors employed in Anglo-Saxon countries, are more likely to get cited than others. As a ‘shortcut' to citation success, we find that research diffusion...

  3. Successful modeling?

    Science.gov (United States)

    Lomnitz, Cinna

    Tichelaar and Ruff [1989] propose to “estimate model variance in complicated geophysical problems,” including the determination of focal depth in earthquakes, by means of unconventional statistical methods such as bootstrapping. They are successful insofar as they are able to duplicate the results from more conventional procedures.

  4. Successful ageing

    DEFF Research Database (Denmark)

    Kusumastuti, Sasmita; Derks, Marloes G. M.; Tellier, Siri

    2016-01-01

    BACKGROUND: Ageing is accompanied by an increased risk of disease and a loss of functioning on several bodily and mental domains and some argue that maintaining health and functioning is essential for a successful old age. Paradoxically, studies have shown that overall wellbeing follows a curvili...

  5. Control rod selecting and driving device

    International Nuclear Information System (INIS)

    Isobe, Hideo.

    1981-01-01

    Purpose: To simultaneously drive a predetermined number of control rods in a predetermined mode by the control of addresses for predetermined number of control rods and read or write of driving codified data to and from the memory by way of a memory controller. Constitution: The system comprises a control rod information selection device for selecting predetermined control rods from a plurality of control rods disposed in a reactor and outputting information for driving them in a predetermined mode, a control rod information output device for codifying the information outputted from the above device and outputting the addresses to the predetermined control rods and driving mode coded data, and a driving device for driving said predetermined control rods in a predetermined mode in accordance with the codified data outputted from the above device, said control rod infromation output device comprising a memory device capable of storing a predetermined number of the codified data and a memory control device for storing the predetermined number of data into the above memory device at a predetermined timing while successively outputting the thus stored predetermined number of data at a predetermined timing. (Seki, T.)

  6. Electromagnetic driving units for complex microrobotic systems

    Science.gov (United States)

    Michel, Frank; Ehrfeld, Wolfgang; Berg, Udo; Degen, Reinhard; Schmitz, Felix

    1998-10-01

    Electromagnetic actuators play an important role in macroscopic robotic systems. In combination with motion transformers, like reducing gear units, angular gears or spindle-screw drives, electromagnetic motors in large product lines ensure the rotational or linear motion of robot driving units and grippers while electromagnets drive valves or part conveyors. In this paper micro actuators and miniaturized motion transformers are introduced which allow a similar development in microrobotics. An electromagnetic motor and a planetary gear box, both with a diameter of 1.9 mm, are already commercially available from the cooperation partner of IMM, the company Dr. Fritz Faulhaber GmbH in Schonaich, Germany. In addition, a motor with a diameter of 2.4 mm is in development. The motors successfully drive an angular gear and a belt drive. A linear stage with a motion range of 7 mm and an overall size as small as 5 X 3.5 X 24 mm3 has been realized involving the motor, a stationary spur gear with zero backlash and a spindle-screw drive. By the use of these commercially available elements complex microrobots can be built up cost-efficiently and rapidly. Furthermore, a batch process has been developed to produce the coils of micro actuator arrays using lithographic techniques with SU-8 resin. In applying these components, the modular construction of complex microrobotic systems becomes feasible.

  7. 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

  8. [Ontogenetic Mechanisms of Explosive Morphological Divergence in the Lake Tana (Ethiopia) Species Flock of Large African Barbs (Labeobarbus; Cyprinidae; Teleostei)].

    Science.gov (United States)

    Shkila, F N; Lazebny, O E; Kapitanova, D V; Abdissa, Belay; Borisov, V B; Smirnov, S V

    2015-01-01

    Species flock of Lake Tana (Ethiopia) large African barbs (Labeobarbus; Cyprinidae; Teleostei) was studied as a model system for investigating ontogenetic mechanisms of the explosive morphological divergence often accompanying sympatric speciation in bony fishes. Comparative morphological analysis carried out with the use ofgeometric morphometric techniques revealed quantitative differences in the head shapes of species under study. Comparative analysis of skull development revealed significant interspecies differences in the temporal characteristics of craniogenesis in these species. These two lines of evidence suggest that heterochronies in craniogenesis underlie divergence in the head shapes of adult Tana barbs. This prediction was verified via experimental changes of temporal characteristics of craniogenesis in L. intermedius, a putative ancestor for the Lake Tana species flock. For this aim, timing and rate of skull development were changed by artificial manipulation of thyroid hormone levels. In sum, it was shown that it is heterochronies that underlie an explosive morphological divergence of the Lake Tana barbs species flock. Our findings together with those reported in the literature suggest variability in the activity of the hypothalamic-pituitary-thyroid axis to contribute to these heterochronies.

  9. Morphological and ontogenetic stratification of abyssal and hadal Eurythenes gryllus sensu lato (Amphipoda: Lysianassoidea) from the Peru-Chile Trench

    Science.gov (United States)

    Eustace, Ryan M.; Ritchie, Heather; Kilgallen, Niamh M.; Piertney, Stuart B.; Jamieson, Alan J.

    2016-03-01

    The globally ubiquitous lysianassoid amphipod, Eurythenes gryllus, has been shown to consist of multiple genetically distinct cryptic taxa, with depth considered a major driver of speciation and morphological divergence. Here we examine morphological variation of E. gryllus sensu lato through a continuous depth distribution that spans from abyssal (3000-6000 m) into hadal depths (>6000 m) in the Peru-Chile Trench (SE Pacific Ocean). Three distinct morphospecies were identified: one was confirmed as being E. magellanicus (4602-5329 m) based on DNA sequence and morphological similarity. The other two morphologically distinct species were named based upon depth of occurrence; Abyssal (4602-6173 m) and Hadal (6173-8074 m). The three Eurythenes morphospecies showed vertical ontogenetic stratification across their bathymetric range, where juveniles were found shallower in their depth range and mature females deeper. Potential ecological and evolutionary drivers that explain the observed patterns of intra and inter-specific structure, such as hydrostatic pressure and topographical isolation, are discussed.

  10. Ontogenetic diet shifts and their incidence on ecological processes: a case study using two morphologically similar stoneflies (Plecoptera)

    Science.gov (United States)

    Céréghino, Régis

    2006-07-01

    Most ecological studies consider conspecific individuals as ecologically equivalent, assuming that inter-instar variation is weak and has a limited influence on functional processes. To test this assumption, we investigated the life history and trophic basis of production in two predatory stoneflies, Perlodes microcephalus and Isoperla acicularis, in a mountain stream. The variety of prey types increased with predator size. However, larvae started their development with a strictly phytophagous diet (3 months), then ingested both vegetal material and animal prey (2-3 months). Finally, larvae were strictly carnivorous when head width reached 1.1 mm. Young (herbivorous) I. acicularis larvae occurred from June to August. Young P. microcephalus larvae hatched in October, and were herbivorous until December, when I. acicularis larvae were omnivorous. Competition for animal prey was likely to occur in the spring, but P. microcephalus grew faster and emerged earlier. The cohort productions were mostly based on carnivory (78.7-90.7%), because most production occurred in later instars. Ontogenetic diet shifts could play a role in the structuring of species assemblages by adjusting species' requirements to the temporal dynamics of environmental conditions, including food availability and biotic interactions. However, their incidence on global processes is quantitatively limited, large individuals having the greatest impacts on the way energy flows.

  11. Ontogenetic changes in the olfactory antennules of the shore crab, Hemigrapsus oregonensis, maintain sniffing function during growth.

    Science.gov (United States)

    Waldrop, Lindsay D; Hann, Miranda; Henry, Amy K; Kim, Agnes; Punjabi, Ayesha; Koehl, M A R

    2015-01-06

    Malacostracan crustaceans capture odours using arrays of chemosensory hairs (aesthetascs) on antennules. Lobsters and stomatopods have sparse aesthetascs on long antennules that flick with a rapid downstroke when water flows between the aesthetascs and a slow return stroke when water is trapped within the array (sniffing). Changes in velocity only cause big differences in flow through an array in a critical range of hair size, spacing and speed. Crabs have short antennules bearing dense arrays of flexible aesthetascs that splay apart during downstroke and clump together during return. Can crabs sniff, and when during ontogeny are they big enough to sniff? Antennules of Hemigrapsus oregonensis representing an ontogenetic series from small juveniles to adults were used to design dynamically scaled physical models. Particle image velocimetry quantified fluid flow through each array and showed that even very small crabs capture a new water sample in their arrays during the downstroke and retain that sample during return stroke. Comparison with isometrically scaled antennules suggests that reduction in aesthetasc flexural stiffness during ontogeny, in addition to increase in aesthetasc number and decrease in relative size, maintain sniffing as crabs grow. Sniffing performance of intermediate-sized juveniles was worse than for smaller and larger crabs. © 2014 The Author(s) Published by the Royal Society. All rights reserved.

  12. Ontogenetic change in the abundance of mycosporine-like amino acids in non-zooxanthellate coral larvae

    Science.gov (United States)

    Yakovleva, Irina M.; Baird, Andrew H.

    2005-11-01

    Although mycosporine-like amino acids (MAAs) have been extensively investigated in reef-building corals, the sources of these MAAs and the process of their interconversion remain a topic of interest. Here we examined ontogenetic change in the abundance of MAAs in planula larvae of the spawning scleractinian coral Goniastrea retiformis in the absence of zooxanthellae and other dietary input. In order to examine the potential contribution of prokaryotes in the synthesis of MAAs in animal tissue, one group of larvae were treated with the antibiotic rifampicin. High concentrations of MAAs (mycosporine-glycine, shinorine, palythinol, asterina-330), were present in the asymbiotic eggs and adults; however, no MAAs were present in the endosymbiotic zooxanthellae. We documented a steady decline in the total MAA concentrations through time in larvae treated with rifampicin; however, in the absence of antibiotic there was a significant increase in the concentration of MAAs, driven by a sharp increase in the abundance of shinorine and palythinol between day 3 and 7. Our results suggest that MAA synthesis and conversion in G. retiformis larvae occurred in the absence of symbiotic zooxanthellae, and indicate a possible contribution of prokaryotes associated with the animal tissue to these processes.

  13. Temperature and ontogenetic effects on color change in the larval salamander species Ambystoma barbouri and Ambystoma texanum

    Energy Technology Data Exchange (ETDEWEB)

    Garcia, T S; Straus, R; Sih, A [Univ. of Kentucky, Dept. of Biological Sciences, Lexington, Kentucky (United States)

    2003-04-01

    Temperature has been shown to affect body color in several species of amphibians. The interaction between color and temperature may also change over larval ontogeny, perhaps because of age-related or seasonal changes in selection pressures on color. We quantified the effects of temperature on the color of the salamander sister species Ambystoma barbouri and Ambystoma texanum over larval ontogeny. We found that early-stage larvae responded to cold temperatures with a dark color relative to that of the warm temperature response. Both species then exhibited an ontogenetic shift in larval color, with larvae becoming lighter with age. Interestingly, older larvae showed decreased plasticity in color change to temperature when compared with younger stages. Older A. texanum larvae exhibited a reversal in the direction of color change, with cold temperatures inducing a lighter color relative to warm temperatures. We suggest that the overall pattern of color change (a plastic color response to temperature for young larvae, a progressive lightening of larvae over development, and an apparent loss of color plasticity to temperature over ontogeny) can be plausibly explained by seasonal changes in environmental factors (temperature, ultraviolet radiation) selecting for body color. (author)

  14. Ontogenetic histological changes in the wood of mango (Mangifera indica L. cv Deshi) exposed to coal-smoke pollution

    Energy Technology Data Exchange (ETDEWEB)

    Gupta, M.C.; Iqbal, M. [Dept. of Botany, New Delhi (India)

    2005-11-01

    Trees of Mangifera indica L. cv Deshi growing at two sites, one heavily polluted due to coal-smoke emanating from a thermal power plant and the other free from such pollution, were examined across their boles (from pith to cambium) to trace ontogenetic changes induced by coal-smoke pollutants in the wood structure with special reference to vessels and fibres. Wood formation was hampered in the polluted environment, as evident from the width of annual rings, indicating an adverse influence of coal-smoke pollutants on the cambial activity. The pollutants inhibited dimensional growth of tracheal elements and promoted frequency and grouping of vessels since early growth stages. The increasing vessel number per square millimeter of wood and the decreasing dimensions of vessel elements and fibres resulted in low values for vulnerability and mesomorphic ratios in the polluted trees. The ratio of the length of fibres to that of vessel elements also decreased. With the growing age, the decline in vulnerability ratio and mesomorphic ratio was enhanced whereas that in the fibre/vessel-element length ratio was minimized.

  15. Ontogenetic variability in old and new collections of Dicranophyllum gallicum Grand’Eury from the late Palaeozoic of Europe

    Directory of Open Access Journals (Sweden)

    Jorik Van der Pas

    2017-10-01

    Full Text Available Dicranophyllum gallicum Grand’Eury is described by means of a morphometric analysis of eighty two samples from various old and new localities in western and central Europe. Stem, leaf cushions, leaf scars, leaves, axillary structures and potential seeds are described in detail, and discussed in comparison to earlier studies. The encountered variability in size and structure is shown to be higher than what was described earlier. The organisation of the leaf cushion and scar density vary gradually with the stem width, while stratigraphic position and ecology do not relate to it. It is concluded that the described variability represents an ontogenetic feature rather than a phylogenetic or ecologic one. The juvenile plants are characterised by small stems, a high leaf scar density and elongated leaf cushions with a dominant apical field, while mature specimens are characterized by a wide stem, a relatively low leaf scar density and relatively wide leaf cushions with a pronounced basal field. Axillary shoots and potential seeds of D. gallicum are described and illustrated in detail for the first time. A reconstruction based on the studied material is presented.

  16. Statistical parametric mapping of the regional distribution and ontogenetic scaling of foot pressures during walking in Asian elephants (Elephas maximus).

    Science.gov (United States)

    Panagiotopoulou, Olga; Pataky, Todd C; Hill, Zoe; Hutchinson, John R

    2012-05-01

    Foot pressure distributions during locomotion have causal links with the anatomical and structural configurations of the foot tissues and the mechanics of locomotion. Elephant feet have five toes bound in a flexible pad of fibrous tissue (digital cushion). Does this specialized foot design control peak foot pressures in such giant animals? And how does body size, such as during ontogenetic growth, influence foot pressures? We addressed these questions by studying foot pressure distributions in elephant feet and their correlation with body mass and centre of pressure trajectories, using statistical parametric mapping (SPM), a neuro-imaging technology. Our results show a positive correlation between body mass and peak pressures, with the highest pressures dominated by the distal ends of the lateral toes (digits 3, 4 and 5). We also demonstrate that pressure reduction in the elephant digital cushion is a complex interaction of its viscoelastic tissue structure and its centre of pressure trajectories, because there is a tendency to avoid rear 'heel' contact as an elephant grows. Using SPM, we present a complete map of pressure distributions in elephant feet during ontogeny by performing statistical analysis at the pixel level across the entire plantar/palmar surface. We hope that our study will build confidence in the potential clinical and scaling applications of mammalian foot pressures, given our findings in support of a link between regional peak pressures and pathogenesis in elephant feet.

  17. Ontogenetic behavior and dispersal of Sacramento River white sturgeon, Acipenser transmontanus, with a note on body color

    Science.gov (United States)

    Kynard, B.; Parker, E.

    2005-01-01

    We studied Sacramento River white sturgeon, Acipenser transmontanus, in the laboratory to develop a conceptual model of ontogenetic behavior and provide insight into probable behavior of wild sturgeon. After hatching, free embryos initiated a low intensity, brief downstream dispersal during which fish swam near the bottom and were photonegative. The weak, short dispersal style and behavior of white sturgeon free embryos contrasts greatly with the intense, long dispersal style and behavior (photopositive and swimming far above the bottom) of dispersing free embryos of other sturgeon species. If spawned eggs are concentrated within a few kilometers downstream of a spawning site, the adaptive significance of the free embryo dispersal is likely to move fish away from the egg deposition site to avoid predation and reduce fish density prior to feeding. Larvae foraged on the open bottom, swam innate fish dispersal and post-dispersal rearing habitat, which is now highly altered by damming and reservoirs. Sacramento River white sturgeon has a two-step downstream dispersal by the free embryo and juvenile life intervals. Diel activity of all life intervals peaked at night, whether fish were dispersing or foraging. Nocturnal behavior is likely a response to predation, which occurs during both activities. An intense black-tail body color was present on foraging larvae, but was weak or absent on the two life intervals that disperse. Black-tail color may be an adaptation for avoiding predation, signaling among aggregated larvae, or both, but not for dispersal. ?? Springer 2005.

  18. Ontogenetic changes in the craniomandibular skeleton of the abelisaurid dinosaur Majungasaurus crenatissimus from the Late Cretaceous of Madagascar

    Directory of Open Access Journals (Sweden)

    Nirina O. Ratsimbaholison

    2016-06-01

    Full Text Available Abelisaurid theropods were one of the most diverse groups of predatory dinosaurs in Gondwana during the Cretaceous. The group is characterized by a tall, wide skull and robust cervical region. This morphology is thought to have facilitated specialized feeding behaviors such as prolonged contact with prey. The Late Cretaceous abelisaurid Majungasaurus crenatissimus typifies this abelisaurid cranial morphotype. Recent fossil discoveries of this species include a partial growth series that allows for the first time an investigation of ontogenetic variation in cranial morphology in a representative abelisaurid. Herein we examine growth trajectories in the shape of individual cranial bones and articulated skulls of Majungasaurus using geometric morphometrics. Several major changes in skull shape were observed through ontogeny, including an increase in the height of the jugal, postorbital, and quadratojugal, an increase in the extent of the contacts between bones, and a decrease in the circumference of the orbit. The skull transitions from relatively short in the smallest individual to tall and robust in large adults, as is seen in other theropods. Such morphological change during ontogeny would likely have resulted in different biomechanical properties and feeding behaviors between small and large individuals. These findings provide a post-hatching developmental framework for understanding the evolution of the distinctive tall skull morphology seen in abelisaurids and other large-sized theropod dinosaurs.

  19. A new species of slender coralsnake from Colombia, and its clinal an ontogenetic variation (Serpentes, Elapidae: Leptomicrurus

    Directory of Open Access Journals (Sweden)

    William W. Lamar

    2003-09-01

    Full Text Available Leptomicrurus renjifoi is described from tropical semi-deciduous forest of the eastern Colombian llanos. It is one of the smallest species in the genus, is most similar to L. scutiventris, and it may be distinguished from known congeners by a combination of color, pattern, and scale characters. Evidence for the recognition of Leptomicrurus is convincing, although its members were recently thought to comprise a closely related assemblage within Micrurus. A supposedly aberrant specimen of L. scutiventris may indicate clinal or ontogenetic variation in patternLeptomicrurus renjifoi es una nueva especie de serpiente elápida del bosque tropical semi-decíduo de los llanos orientales de Colombia. Es una de las especies más pequeñas del género, se asemeja más a L. scutiventris, y se distingue de sus congéneres por una combinación de color, patrón, y carácteres de escamación. Existe suficiente evidencia morfológica para reconocer Leptomicrurus como género independiente, aunque hasta hace poco sus miembros fueron considerados como un grupo compacto dentro del género Micrurus

  20. Temperature and ontogenetic effects on color change in the larval salamander species Ambystoma barbouri and Ambystoma texanum

    International Nuclear Information System (INIS)

    Garcia, T.S.; Straus, R.; Sih, A.

    2003-01-01

    Temperature has been shown to affect body color in several species of amphibians. The interaction between color and temperature may also change over larval ontogeny, perhaps because of age-related or seasonal changes in selection pressures on color. We quantified the effects of temperature on the color of the salamander sister species Ambystoma barbouri and Ambystoma texanum over larval ontogeny. We found that early-stage larvae responded to cold temperatures with a dark color relative to that of the warm temperature response. Both species then exhibited an ontogenetic shift in larval color, with larvae becoming lighter with age. Interestingly, older larvae showed decreased plasticity in color change to temperature when compared with younger stages. Older A. texanum larvae exhibited a reversal in the direction of color change, with cold temperatures inducing a lighter color relative to warm temperatures. We suggest that the overall pattern of color change (a plastic color response to temperature for young larvae, a progressive lightening of larvae over development, and an apparent loss of color plasticity to temperature over ontogeny) can be plausibly explained by seasonal changes in environmental factors (temperature, ultraviolet radiation) selecting for body color. (author)

  1. Radiation drive in laser heated hohlraums

    International Nuclear Information System (INIS)

    Suter, L.J.; Kauffman, R.L.; Darrow, C.B.

    1995-01-01

    Nearly 10 years of Nova experiments and analysis have lead to a relatively detailed quantitative and qualitative understanding of radiation drive in laser heated hohlraums. Our most successful quantitative modelling tool is 2D Lasnex numerical simulations. Analysis of the simulations provides us with insight into the details of the hohlraum drive. In particular we find hohlraum radiation conversion efficiency becomes quite high with longer pulses as the accumulated, high Z blow-off plasma begins to radiate. Extensive Nova experiments corroborate our quantitative and qualitative understanding

  2. Control rod drives

    International Nuclear Information System (INIS)

    Hayakawa, Hiroyasu.

    1979-01-01

    Purpose: To enable rapid control in a simple circuit by providing a motor control device having an electric capacity capable of simultaneously driving all of the control rods rapidly only in the inserting direction as well as a motor controlling device capable of fine control for the insertion and extraction at usual operation. Constitution: The control rod drives comprise a first motor control device capable of finely controlling the control rods both in inserting and extracting directions, a second motor control device capable of rapidly driving the control rods only in the inserting direction, and a first motor switching circuit and a second motor switching circuit switched by switches. Upon issue of a rapid insertion instruction for the control rods, the second motor switching circuit is closed by the switch and the second motor control circuit and driving motors are connected. Thus, each of the control rod driving motors is driven at a high speed in the inserting direction to rapidly insert all of the control rods. (Yoshino, Y.)

  3. Epilepsy and driving

    Directory of Open Access Journals (Sweden)

    Matej Mavrič

    2015-05-01

    Full Text Available Epilepsy poses a risk for all participants in road traffic; therefore people with epilepsy do not meet the criteria for an unlimited driving license. Their driving is affected not only by epileptic seizures causing impaired consciousness and involuntary movements, but also by antiepileptic drugs with their many unwanted affects. The experts have not yet agreed on whether people with epilepsy have an increased risk of experiencing a road traffic accident. However, recent data suggests that the overall risk is lower compared to other medical conditions. Scientific evidence forms the basis of legislation, which by limiting people with epilepsy, enables all participants in road traffic to drive in the safest possible environment. The legislation that governs epilepsy and driving in Slovenia has been recently thoroughly reformed and thus allows a less discriminatory management of people with epilepsy. Although people with epilepsy experience many issues in their daily life, including their personal relationships and employment, they often list the need for driving as a top concern in surveys. General physicians play an important role in managing the issues of people with epilepsy.

  4. Self-rated Driving and Driving Safety in Older Adults

    OpenAIRE

    Ross, Lesley A.; Dodson, Joan; Edwards, Jerri D.; Ackerman, Michelle L.; Ball, Karlene

    2012-01-01

    Many U.S. states rely on older adults to self-regulate their driving and determine when driving is no longer a safe option. However, the relationship of older adults’ self-rated driving in terms of actual driving competency outcomes is unclear. The current study investigates self-rated driving in terms of (1) systematic differences between older adults with high (good/excellent) versus low (poor/fair/average) self-ratings, and (2) the predictive nature of self-rated driving to adverse driving...

  5. Ontogenetic Variation in the Diet Composition of Glossogobius Giuris from Taal Lake, Batangas, Philippines

    Directory of Open Access Journals (Sweden)

    Jodi Belina A. Bejer

    2015-11-01

    Full Text Available Glossogobius giuris is an indigenous fish in Taal Lake and is considered to be very important not only due to its reasonable price but also because unlike any other fish, it contains all the nutrients and essential amino acids. Furthermore, this fish is also suitable candidate for artificial culture in the future. Knowledge on the food habits or diet composition is important in evaluating the feeding success of G.giuris which can lead to successful management of stocks in the future. Based on the relative importance, it was found out that the insect larvae and debris were the most important prey items of the juvenile G.giuris while the nematode was the least important. Among the prey items consumed by the adult G.giuris, crustacean eggs and fish larvae had the highest relative importance while the cladocerans had the lowest importance. This revealed that the small or juvenile G.giuris tended to consume more midge larvae and copepods. The adult fish tended to consume mostly crustacean eggs and fish. The trophic level of the juvenile and adult G.giuris revealed that this fish belongs to the second and third level. Based on the calculated trophic level, it showed that this fish can be carnivore, herbivore and omnivore. Lastly, there was a significant difference in the trophic level of the two groups of G.giuris, the juvenile and the adult.

  6. Driving Extreme Efficiency to Market

    Science.gov (United States)

    Garbesi, Karina

    2014-03-01

    The rapid development of extremely energy efficient appliances and equipment is essential to curtail catastrophic climate disruption. This will require the on-going development of products that apply all best-practices and that take advantage of the synergies of hybridization and building integration. Beyond that, it requires the development of new disruptive technologies and concepts. To facilitate these goals, in 2011 the Lawrence Berkeley National Laboratory and the U.S. Department of Energy launched the Max Tech and Beyond Design Competition for Ultra-Low-Energy-Use Appliances and Equipment. Now in its third year, the competition supports faculty-lead student design teams at U.S. universities to develop and test new technology prototypes. This talk describes what the competition and the Max Tech Program are doing to drive such rapid technology progress and to facilitate the entry to the market of successful Max Tech prototypes. The talk also initiates a discussion of physicists' unique role in driving that technology progress faster and farther. Emerging Technologies, Building Technologies Office, U.S. Department of Energy.

  7. Gears and gear drives

    CERN Document Server

    Jelaska, Damir T

    2012-01-01

    Understanding how gears are formed and how they interact or 'mesh' with each other is essential when designing equipment that uses gears or gear trains. The way in which gear teeth are formed and how they mesh is determined by their geometry and kinematics, which is the topic of this book.  Gears and Gear Drives provides the reader with comprehensive coverage of gears and gear drives. Spur, helical, bevel, worm and planetary gears are all covered, with consideration given to their classification, geometry, kinematics, accuracy control, load capacity and manufacturing. Cylindric

  8. Toyota hybrid synergy drive

    Energy Technology Data Exchange (ETDEWEB)

    Gautschi, H.

    2008-07-01

    This presentation made at the Swiss 2008 research conference on traffic by Hannes Gautschi, director of service and training at the Toyota company in Switzerland, takes a look at Toyota's hybrid drive vehicles. The construction of the vehicles and their combined combustion engines and electric generators and drives is presented and the combined operation of these components is described. Braking and energy recovery are discussed. Figures on the performance, fuel consumption and CO{sub 2} output of the hybrid vehicles are compared with those of conventional vehicles.

  9. Variation in Honey Bee Gut Microbial Diversity Affected by Ontogenetic Stage, Age and Geographic Location

    Science.gov (United States)

    Hroncova, Zuzana; Havlik, Jaroslav; Killer, Jiri; Doskocil, Ivo; Tyl, Jan; Kamler, Martin; Titera, Dalibor; Hakl, Josef; Mrazek, Jakub; Bunesova, Vera; Rada, Vojtech

    2015-01-01

    Social honey bees, Apis mellifera, host a set of distinct microbiota, which is similar across the continents and various honey bee species. Some of these bacteria, such as lactobacilli, have been linked to immunity and defence against pathogens. Pathogen defence is crucial, particularly in larval stages, as many pathogens affect the brood. However, information on larval microbiota is conflicting. Seven developmental stages and drones were sampled from 3 colonies at each of the 4 geographic locations of A. mellifera carnica, and the samples were maintained separately for analysis. We analysed the variation and abundance of important bacterial groups and taxa in the collected bees. Major bacterial groups were evaluated over the entire life of honey bee individuals, where digestive tracts of same aged bees were sampled in the course of time. The results showed that the microbial tract of 6-day-old 5th instar larvae were nearly equally rich in total microbial counts per total digestive tract weight as foraging bees, showing a high percentage of various lactobacilli (Firmicutes) and Gilliamella apicola (Gammaproteobacteria 1). However, during pupation, microbial counts were significantly reduced but recovered quickly by 6 days post-emergence. Between emergence and day 6, imago reached the highest counts of Firmicutes and Gammaproteobacteria, which then gradually declined with bee age. Redundancy analysis conducted using denaturing gradient gel electrophoresis identified bacterial species that were characteristic of each developmental stage. The results suggest that 3-day 4th instar larvae contain low microbial counts that increase 2-fold by day 6 and then decrease during pupation. Microbial succession of the imago begins soon after emergence. We found that bacterial counts do not show only yearly cycles within a colony, but vary on the individual level. Sampling and pooling adult bees or 6th day larvae may lead to high errors and variability, as both of these stages may

  10. The development of collective personality: the ontogenetic drivers of behavioral variation across groups

    Directory of Open Access Journals (Sweden)

    Sarah E Bengston

    2014-12-01

    Full Text Available For the past decade, the study of personality has become a topic on the frontier of behavioral ecology. However, most studies have focused on exploring inter-individual behavioral variation in solitary animals, and few account for the role that social interactions may have on the development of an individual’s personality. Moreover, a social group may exhibit collective personality: an emergent behavioral phenotype displayed at the group-level, which is not necessarily the sum or average of individual personalities within that group. The social environment, in many cases, can determine group success, which then influences the relative success of all the individuals in that group. In addition, group-level personality may itself evolve, subject to the same selection pressures as individual-level behavioral variation, when the group is a unit under selection. Therefore, we reason that understanding how collective personalities emerge and change over time will be imperative to understanding individual- and group-level behavioral evolution.Personality is considered to be fixed over an individual’s lifetime. However, behavior may shift throughout development, particularly during adolescence. Therefore, juvenile behavior should not be compared with adult behavior when assessing personality. Similarly, as conditions within a group and/or the local environment can shift, group behavior may similarly fluctuate as it matures. We discuss potential within-group factors, such as group initiation, group maturation, genetic make-up of the group, and the internal social environment, and external factors, such as well as how local environment may play a role in generating group-level personalities. There are a variety of studies that explore group development or quantify group personality, but few that integrate both processes. Therefore, we conclude by discussing potential ways to evaluate development of collective personality, and propose several focal

  11. Comparing Expert and Novice Driving Behavior in a Driving Simulator

    Directory of Open Access Journals (Sweden)

    Hiran B. Ekanayake

    2014-02-01

    Full Text Available This paper presents a study focused on comparing driving behavior of expert and novice drivers in a mid-range driving simulator with the intention of evaluating the validity of driving simulators for driver training. For the investigation, measurements of performance, psychophysiological measurements, and self-reported user experience under different conditions of driving tracks and driving sessions were analyzed. We calculated correlations between quantitative and qualitative measures to enhance the reliability of the findings. The experiment was conducted involving 14 experienced drivers and 17 novice drivers. The results indicate that driving behaviors of expert and novice drivers differ from each other in several ways but it heavily depends on the characteristics of the task. Moreover, our belief is that the analytical framework proposed in this paper can be used as a tool for selecting appropriate driving tasks as well as for evaluating driving performance in driving simulators.

  12. Driving skills after whiplash.

    Science.gov (United States)

    Gimse, R; Bjørgen, I A; Straume, A

    1997-09-01

    Previous studies have shown that some persons with longlasting problems after whiplash have changed eye movements. These changes have been related to disturbance of the posture control system. The question raised in the present study is whether such disturbances can influence daily life functions connected with balance, position and external movements, such as car driving. A group of 23 persons with disturbed eye movements due to whiplash injury, was tested in a driving simulator, together with a closely matched control group. The results revealed significant differences between the two groups with respect to response times to the traffic signs presented, identification of type of sign, as well as steering precision while the subjects' attention was directed to the process of identifying the signs. Alternative explanations such as driving experience, pain, medication or malingering are at least partly controlled for, but cannot completely be ruled out. A distorted posture control system leading to disturbance of eye movements seems to be the most likely primary causative factor, but these disturbances are most certainly complexly determined. Reduced attention capacity is considered to be a mediating secondary factor. Registration of eye movements may be a useful diagnostic tool to evaluate driving skill after whiplash.

  13. Gaze-controlled Driving

    DEFF Research Database (Denmark)

    Tall, Martin; Alapetite, Alexandre; San Agustin, Javier

    2009-01-01

    We investigate if the gaze (point of regard) can control a remote vehicle driving on a racing track. Five different input devices (on-screen buttons, mouse-pointing low-cost webcam eye tracker and two commercial eye tracking systems) provide heading and speed control on the scene view transmitted...

  14. Gas turbine drives

    Energy Technology Data Exchange (ETDEWEB)

    1981-01-01

    Developments in gas turbine drives are reviewed, e.g., low weight per unit power and thrust-weight ratio, fast availability of the maximum speed, absolute resistance to cold and to droplet formation vibrationeless run, and low exhaust gas temperatures. Applications in aeronautic engineering (turbofan), power stations, marine propulsion systems, railways and road transportation vehicles are mentioned.

  15. Chaos in drive systems

    Directory of Open Access Journals (Sweden)

    Kratochvíl C.

    2007-10-01

    Full Text Available The purpose of this article is to provide an elementary introduction to the subject of chaos in the electromechanical drive systems. In this article, we explore chaotic solutions of maps and continuous time systems. These solutions are also bounded like equilibrium, periodic and quasiperiodic solutions.

  16. Electric Drive Study

    Science.gov (United States)

    1987-03-01

    compound promises to reduce weight of future permanent magnet motors by 20 to 30 percent; a similar reduction is expected in size (approximately 20...drive systems. The AC permanent magnet (brushless DC motor) is rapidly evolving and will replace most electrically excited machines. Permanent magnet motors using

  17. Electric-Drive Vehicles

    Energy Technology Data Exchange (ETDEWEB)

    Septon, Kendall K [National Renewable Energy Laboratory (NREL), Golden, CO (United States)

    2017-09-11

    Electric-drive vehicles use electricity as their primary fuel or to improve the efficiency of conventional vehicle designs. These vehicles can be divided into three categories: Hybrid electric vehicles (HEVs), Plug-in hybrid electric vehicles (PHEVs), All-electric vehicles (EVs). Together, PHEVs and EVs can also be referred to as plug-in electric vehicles (PEVs).

  18. Electric-Drive Vehicles

    Energy Technology Data Exchange (ETDEWEB)

    None

    2017-09-01

    Electric-drive vehicles use electricity as their primary fuel or to improve the efficiency of conventional vehicle designs. These vehicles can be divided into three categories: Hybrid electric vehicles (HEVs), Plug-in hybrid electric vehicles (PHEVs), All-electric vehicles (EVs). Together, PHEVs and EVs can also be referred to as plug-in electric vehicles (PEVs).

  19. Driving While Intoxicated.

    Science.gov (United States)

    Brick, John

    Alcohol intoxication increases the risk of highway accidents, the relative risk of crash probability increasing as a function of blood alcohol content (BAC). Because alcohol use is more prevalent than use of other drugs, more is known about the relationship between alcohol use and driving. Most states presume a BAC of .10% to be evidence of drunk…

  20. Seasonal and ontogenetic changes of mycosporine-like amino acids in planktonic organisms from an alpine lake

    Science.gov (United States)

    Tartarotti, Barbara; Sommaruga, Ruben

    2011-01-01

    We studied the quantitative and qualitative mycosporine-like amino acid (MAA) composition in phytoplankton and the copepod Cyclops abyssorum tatricus from an alpine lake over a 15-month period. Up to eight MAAs were identified in the samples, with shinorine being predominant. The MAAs occurred year round and showed a strong seasonal pattern. Compared with ice-cover periods, concentrations during the summer were on average 3.6 and 3.0 times higher in phytoplankton and C. abyssorum tatricus, respectively. During the summer, the contents of MAAs in phytoplankton decreased with depth, suggesting their photoprotective role. Chlorophyll a-specific concentrations of MAAs in phytoplankton correlated significantly with the incident solar radiation and ultraviolet (UV) water transparency (r2 ≤ 0.36), however, the strongest relationship was found with water temperature (r2 = 0.67). In zooplankton, highest contents of MAAs were found in eggs, nauplii, and young copepodids, presumably providing a high level of photoprotection for progeny. Proportions of the dominant MAAs in the copepod showed seasonal and ontogenetic variations, which were consistent with relative changes in the predominant MAA, but not other abundant MAAs, in phytoplankton. Considering a time lag of approximately 1 month between the synthesis and subsequent accumulation of these compounds, MAA concentrations in late copepodid to adult life stages were significantly correlated to those in phytoplankton. Annual patterns in MAAs with high concentrations during periods of elevated environmental stress are consistent with the idea that these compounds play an important role in protecting aquatic organisms against UV damage. PMID:21258624

  1. Ontogenetic investigation of underwater hearing capabilities in loggerhead sea turtles (Caretta caretta) using a dual testing approach.

    Science.gov (United States)

    Lavender, Ashley L; Bartol, Soraya M; Bartol, Ian K

    2014-07-15

    Sea turtles reside in different acoustic environments with each life history stage and may have different hearing capacity throughout ontogeny. For this study, two independent yet complementary techniques for hearing assessment, i.e. behavioral and electrophysiological audiometry, were employed to (1) measure hearing in post-hatchling and juvenile loggerhead sea turtles Caretta caretta (19-62 cm straight carapace length) to determine whether these migratory turtles exhibit an ontogenetic shift in underwater auditory detection and (2) evaluate whether hearing frequency range and threshold sensitivity are consistent in behavioral and electrophysiological tests. Behavioral trials first required training turtles to respond to known frequencies, a multi-stage, time-intensive process, and then recording their behavior when they were presented with sound stimuli from an underwater speaker using a two-response forced-choice paradigm. Electrophysiological experiments involved submerging restrained, fully conscious turtles just below the air-water interface and recording auditory evoked potentials (AEPs) when sound stimuli were presented using an underwater speaker. No significant differences in behavior-derived auditory thresholds or AEP-derived auditory thresholds were detected between post-hatchling and juvenile sea turtles. While hearing frequency range (50-1000/1100 Hz) and highest sensitivity (100-400 Hz) were consistent in audiograms pooled by size class for both behavior and AEP experiments, both post-hatchlings and juveniles had significantly higher AEP-derived than behavior-derived auditory thresholds, indicating that behavioral assessment is a more sensitive testing approach. The results from this study suggest that post-hatchling and juvenile loggerhead sea turtles are low-frequency specialists, exhibiting little differences in threshold sensitivity and frequency bandwidth despite residence in acoustically distinct environments throughout ontogeny. © 2014

  2. Ontogenetic behavior and migration of Atlantic sturgeon, Acipenser oxyrinchus oxyrinchus, and shortnose sturgeon, A. brevirostrum, with notes on social behavior

    Science.gov (United States)

    Kynard, B.; Horgan, M.

    2002-01-01

    Ontogenetic behavior of Hudson River Atlantic sturgeon and Connecticut River shortnose sturgeon early life intervals were similar during laboratory observations. After hatching, free embryos were photonegative and sought cover. When embryos developed into larvae, fish left cover, were photopositive, and initiated downstream migration. Free embryos may remain at the spawning site instead of migrating downstream because the risk of predation at spawning sites is low. The two species are sympatric, but not closely related, so the similarities in innate behaviors suggest common adaptations, not phylogenetlc relationship. Atlantic sturgeon migrated downstream for 12 days (peak, first 6 days), shortnose sturgeon migrated for 3 days, and year-0 juveniles of both species did not resume downstream migration. Short or long migrations of larvae may reflect different styles related to the total migratory distance from spawning sites to juvenile rearing areas. Atlantic sturgeon need to move a short distance to reach rearing areas and they had a long 1-step migration of 6-12 days. In contrast, shortnose sturgeon need to move a long distance to reach all rearing areas. This may be accomplished by a 2-step migration, of which the brief migration of larvae is only the first step. Early migrant Atlantic sturgeon were nocturnal, while late migrants were diurnal, and shortnose sturgeon were diurnal. These diel differences may also be adaptations for long (Atlantic sturgeon) or short (shortnose sturgeon) migrations. Cultured shortnose sturgeon, and possibly Atlantic sturgeon, have a dominance hierarchy with large fish dominant when competing for limited foraging space. Social behavior may be more important in the life history of wild sturgeons than is generally recognized.

  3. Rod drive and latching mechanism

    International Nuclear Information System (INIS)

    Veronesi, L.; Sherwood, D.G.

    1982-01-01

    Hydraulic drive and latching mechanisms for driving reactivity control mechanisms in nuclear reactors are described. Preferably, the pressurized reactor coolant is utilized to raise the drive rod into contact with and to pivot the latching mechanism so as to allow the drive rod to pass the latching mechanism. The pressure in the housing may then be equalized which allows the drive rod to move downwardly into contact with the latching mechanism but to hold the shaft in a raised position with respect to the reactor core. Once again, the reactor coolant pressure may be utilized to raise the drive rod and thus pivot the latching mechanism so that the drive rod passes above the latching mechanism. Again, the mechanism pressure can be equalized which allows the drive rod to fall and pass by the latching mechanism so that the drive rod approaches the reactor core. (author)

  4. Using a Novel Absolute Ontogenetic Age Determination Technique to Calculate the Timing of Tooth Eruption in the Saber-Toothed Cat, Smilodon fatalis.

    Directory of Open Access Journals (Sweden)

    M Aleksander Wysocki

    Full Text Available Despite the superb fossil record of the saber-toothed cat, Smilodon fatalis, ontogenetic age determination for this and other ancient species remains a challenge. The present study utilizes a new technique, a combination of data from stable oxygen isotope analyses and micro-computed tomography, to establish the eruption rate for the permanent upper canines in Smilodon fatalis. The results imply an eruption rate of 6.0 millimeters per month, which is similar to a previously published average enamel growth rate of the S. fatalis upper canines (5.8 millimeters per month. Utilizing the upper canine growth rate, the upper canine eruption rate, and a previously published tooth replacement sequence, this study calculates absolute ontogenetic age ranges of tooth development and eruption in S. fatalis. The timing of tooth eruption is compared between S. fatalis and several extant conical-toothed felids, such as the African lion (Panthera leo. Results suggest that the permanent dentition of S. fatalis, except for the upper canines, was fully erupted by 14 to 22 months, and that the upper canines finished erupting at about 34 to 41 months. Based on these developmental age calculations, S. fatalis individuals less than 4 to 7 months of age were not typically preserved at Rancho La Brea. On the whole, S. fatalis appears to have had delayed dental development compared to dental development in similar-sized extant felids. This technique for absolute ontogenetic age determination can be replicated in other ancient species, including non-saber-toothed taxa, as long as the timing of growth initiation and growth rate can be determined for a specific feature, such as a tooth, and that growth period overlaps with the development of the other features under investigation.

  5. Modulation of carbon and nitrogen allocation in Urtica dioica and Plantago major by elevated CO{sub 2}. Impact of accumulation of nonstructural carbohydrates and ontogenetic drift

    Energy Technology Data Exchange (ETDEWEB)

    Hertog, J. den; Stulen, I.; Fonseca, F.; Delea, P.

    1996-10-01

    Doubling the atmospheric CO{sub 2} concentration from 350 to 700 {mu} l{sup -1} increased the relative growth rate (RGR) of hydroponically grown Urtica dioica L. and Plantagomajor ssp. pleiospherma Pilger only for the first 10-14 days. Previous experiments with P. major indicated that RGR did not respond i proportion to the rate of photosynthesis. The impact of changes in leaf morphology, dry matter partitioning, dry matter chemical composition and ontogenetic drift on this discrepancy is analysed. Soon after the start of the treatment, carbohydrate concentrations were higher at elevated CO{sub 2}; largely due to starch accumulation. An increase in the percentage of leaf dry matter and decreases in the specific leaf area (SLA) and the shoot nitrogen concentration were correlated with an increase in the total nonstructural carbohydrate concentration (TNC). A combination of accumulation of soluble sugars and starch and ontogenetic drift explains the decrease in SLA at the elevated CO{sub 2} level. A similar ontogenetic effect of elevated CO{sub 2} was observed on the specific root length (SRL). Shoot nitrogen concentration and percentage leaf dry matter were not affected. The net diurnal fluctuation of the carbohydrate pool in P. major was equal for both CO{sub 2} concentrations, indicating that the growth response to elevated CO{sub 2} may be ruled by other variables such as sink strength. Elevated CO{sub 2} did not greatly influence the partitioning of nitrogen between soluble and insoluble, reduced N and nitrate, nor the allocation of dry matter between leaf, stem and root. That the root to shoot ratio (F/S) was not affected by elevated CO{sub 2} implies that, to maintain a balanced activity between roots and shoot, no shift in partitioning of dry matter upon doubling of the atmospheric CO{sub 2} concentration is required. (AB)

  6. Using a Novel Absolute Ontogenetic Age Determination Technique to Calculate the Timing of Tooth Eruption in the Saber-Toothed Cat, Smilodon fatalis.

    Science.gov (United States)

    Wysocki, M Aleksander; Feranec, Robert S; Tseng, Zhijie Jack; Bjornsson, Christopher S

    2015-01-01

    Despite the superb fossil record of the saber-toothed cat, Smilodon fatalis, ontogenetic age determination for this and other ancient species remains a challenge. The present study utilizes a new technique, a combination of data from stable oxygen isotope analyses and micro-computed tomography, to establish the eruption rate for the permanent upper canines in Smilodon fatalis. The results imply an eruption rate of 6.0 millimeters per month, which is similar to a previously published average enamel growth rate of the S. fatalis upper canines (5.8 millimeters per month). Utilizing the upper canine growth rate, the upper canine eruption rate, and a previously published tooth replacement sequence, this study calculates absolute ontogenetic age ranges of tooth development and eruption in S. fatalis. The timing of tooth eruption is compared between S. fatalis and several extant conical-toothed felids, such as the African lion (Panthera leo). Results suggest that the permanent dentition of S. fatalis, except for the upper canines, was fully erupted by 14 to 22 months, and that the upper canines finished erupting at about 34 to 41 months. Based on these developmental age calculations, S. fatalis individuals less than 4 to 7 months of age were not typically preserved at Rancho La Brea. On the whole, S. fatalis appears to have had delayed dental development compared to dental development in similar-sized extant felids. This technique for absolute ontogenetic age determination can be replicated in other ancient species, including non-saber-toothed taxa, as long as the timing of growth initiation and growth rate can be determined for a specific feature, such as a tooth, and that growth period overlaps with the development of the other features under investigation.

  7. Electrical drives for direct drive renewable energy systems

    CERN Document Server

    Mueller, Markus

    2013-01-01

    Wind turbine gearboxes present major reliability issues, leading to great interest in the current development of gearless direct-drive wind energy systems. Offering high reliability, high efficiency and low maintenance, developments in these direct-drive systems point the way to the next generation of wind power, and Electrical drives for direct drive renewable energy systems is an authoritative guide to their design, development and operation. Part one outlines electrical drive technology, beginning with an overview of electrical generators for direct drive systems. Principles of electrical design for permanent magnet generators are discussed, followed by electrical, thermal and structural generator design and systems integration. A review of power electronic converter technology and power electronic converter systems for direct drive renewable energy applications is then conducted. Part two then focuses on wind and marine applications, beginning with a commercial overview of wind turbine drive systems and a...

  8. An Analytic Approach to Cascade Control Design for Hydraulic Valve-Cylinder Drives

    DEFF Research Database (Denmark)

    Schmidt, Lasse; Hansen, Anders Hedegaard; Andersen, Torben O.

    2016-01-01

    , unfortunately not present in valve-operated hydraulic drives. This paper considers a cascade control approach for hydraulic valve-cylinder drives motivated by the fact that this may be applied to successfully suppress nonlinearities. The drive is pre-compensated utilizing a pressure updated inverse valve flow...

  9. Don't Let Drinking and Driving Kill the Pleasure of the Prom.

    Science.gov (United States)

    Zakariya, Sally Banks

    1984-01-01

    This article describes programs successfully combating drunk driving among teenagers in Maine, Virginia, and New York, discusses the nationwide movement called Students Against Driving Drunk (SADD), anti-drunk driving legislation, and the need for increased alcohol education, and provides information on how to emphasize student sobriety and safety…

  10. A novel length back-calculation approach accounting for ontogenetic changes in the fish length - otolith size relationship during the early life of sprat (Sprattus sprattus)

    DEFF Research Database (Denmark)

    Guenther, Claudia C.; Temming, Axel; Baumann, Hannes

    2012-01-01

    An individual-based length back-calculation method was developed for juvenile Baltic sprat (Sprattus sprattus), accounting for ontogenetic changes in the relationship between fish length and otolith length. In sprat, metamorphosis from larvae to juveniles is characterized by the coincidence of low...... length growth, strong growth in body height, and maximal otolith growth. Consequently, the method identifies a point of metamorphosis for an individual as the otolith radius at maximum increment widths. By incorporating this information in our back-calculation method, estimated length growth...

  11. Driving towards ecotechnologies.

    Science.gov (United States)

    Najjar, Devora A; Normandin, Avery M; Strait, Elizabeth A; Esvelt, Kevin M

    2017-12-01

    The prospect of using genetic methods to target vector, parasite, and reservoir species offers tremendous potential benefits to public health, but the use of genome editing to alter the shared environment will require special attention to public perception and community governance in order to benefit the world. Public skepticism combined with the media scrutiny of gene drive systems could easily derail unpopular projects entirely, especially given the potential for trade barriers to be raised against countries that employ self-propagating gene drives. Hence, open and community-guided development of thoughtfully chosen applications is not only the most ethical approach, but also the most likely to overcome the economic, social, and diplomatic barriers. Here we review current and past attempts to alter ecosystems using biological methods, identify key determinants of social acceptance, and chart a stepwise path for developers towards safe and widely supported use.

  12. Control rod drives

    International Nuclear Information System (INIS)

    Asano, Hiromitsu.

    1979-01-01

    Purpose: To drive control rods at an optimum safety speed corresponding to the reactor core output. Constitution: The reactor power is detected by a neutron detector and the output signal is applied to a process computer. The process computer issues a signal representing the reactor core output, which is converted through a function generator into a signal representing the safety speed of control rods. The converted signal is further supplied to a V/F converter and converted into a pulse signal. The pulse signal is inputted to a step motor driving circuit, which actuates a step motor to operate the control rods always at a safety speed corresponding to the reactor core power. (Furukawa, Y.)

  13. Safety rod driving device

    International Nuclear Information System (INIS)

    Murakami, Kiyonobu; Kurosaki, Akira.

    1988-01-01

    Purpose: To rapidly insert safety rods for a criticality experiment device into a reactor core container to stop the criticality reaction thereby prevent reactivity accidents. Constitution: A cylinder device having a safety rod as a cylinder rod attached with a piston at one end is constituted. The piston is elevated by pressurized air and attracted and fixed by an electromagnet which is a stationary device disposed at the upper portion of the cylinder. If the current supply to the electromagnet is disconnected, the safety rod constituting the cylinder rod is fallen together with the piston to the lower portion of the cylinder. Since the cylinder rod driving device has neither electrical motor nor driving screw as in the conventional device, necessary space can be reduced and the weight is decreased. In addition, since the inside of the nuclear reactor can easily be shielded completely from the external atmosphere, leakage of radioactive materials can be prevented. (Horiuchi, T.)

  14. Control rod drive mechanism

    International Nuclear Information System (INIS)

    Futatsugi, Masao; Goto, Mikihiko.

    1976-01-01

    Purpose: To provide a control rod drive mechanism using water as an operating source, which prevents a phenomenon for forming two-layers of water in the neighbourhood of a return nozzle in a reactor to limit formation of excessive thermal stress to improve a safety. Constitution: In the control rod drive mechanism of the present invention, a heating device is installed in the neighbourhood of a pressure container for a reactor. This heating device is provided to heat return water in the reactor to a level equal to the temperature of reactor water thereby preventing a phenomenon for forming two-layers of water in the reactor. This limits formation of thermal stress in the return nozzle in the reactor. Accordingly, it is possible to minimize damages in the return nozzle portion and yet a possibility of failure in reactor water. (Kawakami, Y.)

  15. A rotary drive

    International Nuclear Information System (INIS)

    Causer, R.

    1983-01-01

    A rotary drive for a manipulator or teleoperator comprises a ring member freely rotatable about an eccentric boss extending from an input driver shaft. The ring member has a tapered rim portion wedged between two resiliently biassed friction rings of larger diameter than the ring member and coaxial with the driver shaft, and the ring member is rotatably connected to an output driven shaft. The rotary drive provides a considerable velocity ratio, and also provides a safety feature in that friction between the rim portion and the friction rings only causes rotation of the driven shaft if the load on the driven shaft is less than a certain limiting value. This limiting value may be varied by adjusting the resilient bias on the friction rings. (author)

  16. Driving and engine cycles

    CERN Document Server

    Giakoumis, Evangelos G

    2017-01-01

    This book presents in detail the most important driving and engine cycles used for the certification and testing of new vehicles and engines around the world. It covers chassis and engine-dynamometer cycles for passenger cars, light-duty vans, heavy-duty engines, non-road engines and motorcycles, offering detailed historical information and critical review. The book also provides detailed examples from SI and diesel engines and vehicles operating during various cycles, with a focus on how the engine behaves during transients and how this is reflected in emitted pollutants, CO2 and after-treatment systems operation. It describes the measurement methods for the testing of new vehicles and essential information on the procedure for creating a driving cycle. Lastly, it presents detailed technical specifications on the most important chassis-dynamometer cycles around the world, together with a direct comparison of those cycles.

  17. Driving electrostatic transducers

    DEFF Research Database (Denmark)

    Nielsen, Dennis; Knott, Arnold; Andersen, Michael A. E.

    2013-01-01

    Electrostatic transducers represent a very interesting alternative to the traditional inefficient electrodynamic transducers. In order to establish the full potential of these transducers, power amplifiers which fulfill the strict requirements imposed by such loads (high impedance, frequency...... depended, nonlinear and high bias voltage for linearization) must be developed. This paper analyzes power stages and bias configurations suitable for driving an electrostatic transducer. Measurement results of a 300 V prototype amplifier are shown. Measuring THD across a high impedance source is discussed...

  18. Control rod drive mechanism

    International Nuclear Information System (INIS)

    Mizuno, Katsuyuki.

    1976-01-01

    Object: To restrict the reduction in performance due to stress corrosion cracks by making use of condensate produced in a turbine steam condenser. Structure: Water produced in a turbine steam condenser is forced into a condensed water desalting unit by low pressure condensate pump. The condensate is purified and then forced by a high pressure condensate pump into a feedwater heater for heating before it is returned to the reactor by a feedwater pump. Part of the condensate issuing from the condensate desalting unit is branched from the remaining portion at a point upstream the pump and is withdrawn into a control rod drive water pump after passing through a motordriven bypass valve, an orifice and a condenser water level control valve, is pressurized in the control rod drive water desalting unit and supplied to a control rod drive water pressure system. The control rod is vertically moved by the valve operation of the water pressure system. Since water of high oxygen concentration does not enter during normal operation, it is possible to prevent the stress cracking of the stainless steel apparatus. (Nakamura, S.)

  19. Motor car driving; Kraftfahrzeugfuehrung

    Energy Technology Data Exchange (ETDEWEB)

    Juergensohn, T. [Technische Univ. Berlin (Germany). ISS-Fahrzeugtechnik; Timpe, K.P. (eds.) [Technische Univ. Berlin (DE). Zentrum Mensch-Maschine-Systeme (ZMMS)

    2001-07-01

    This is the first comprehensive book on motor car driving, i.e. all aspects of motor car technology that cannot be looked at separately from the needs, characteristics and limitations of the human driver. This includes ergonomics as well as the design of the driver interface in consideration of the findings of cognitive science, problems of driving simulation in the context of simulation of technical systems, problems relating to optimal car automation up to traffic psychology. The book is in honour of Prof. Dr. Willumeit who died in summer 2000. Prof. Willumeit was one of the few scientists in Germany who had been an expert on all aspects of motor car driving for many years. [German] Erstmalig wird das Thema der Fahrzeugfuehrung geschlossen dargestellt. Die Thematik der 'Kraftfahrzeugfuehrung' umfasst in diesem Zusammenhang alle Aspekte der Kraftfahrzeugtechnik, die nicht isoliert von den Erfordernissen, Eigenschaften und Grenzen des menschlichen Fahrers betrachtet werden koennen. Dies beinhaltet u.a. Probleme der Ergonomie, aber auch Fragen nach einer kognitionswissenschaftlich unterstuetzten Schnittstellengestaltung, Fragen der Simulation des Fahrverhalten im Kontext der Simulation technischer Systeme oder Fragen einer optimalen Fahrzeugautomatisierung bis hin zu verkehrspsychologischen Aspekten. Das Buch ist als Gedenkband fuer Prof. Dr. Willumeit konzipiert, der im Sommer 2000 verstarb. Prof. Willumeit war einer der wenigen Wissenschaftler in Deutschland, der ueber viele Jahre diese Thematik der Kraftfahrzeugfuehrung in ihrer vollen Breite verfolgte. (orig.)

  20. Control rod drive

    International Nuclear Information System (INIS)

    Watando, Kosaku; Tanaka, Yuzo; Mizumura, Yasuhiro; Hosono, Kazuya.

    1975-01-01

    Object: To provide a simple and compact construction of an apparatus for driving a drive shaft inside with a magnetic force from the outside of the primary system water side. Structure: The weight of a plunger provided with an attraction plate is supported by a plunger lift spring means so as to provide a buffer action at the time of momentary movement while also permitting the load on lift coil to be constituted solely by the load on the drive shaft. In addition, by arranging the attraction plate and lift coil so that they face each other with a small gap there-between, it is made possible to reduce the size and permit efficient utilization of the attracting force. Because of the small size, cooling can be simply carried out. Further, since there is no mechanical penetration portion, there is no possibility of leakage of the primary system water. Furthermore, concentration of load on a latch pin is prevented by arranging so that with a structure the load of the control rod to be directly beared through the scrum latch. (Kamimura, M.)

  1. Successful Aging

    Directory of Open Access Journals (Sweden)

    Taufiqurrahman Nasihun

    2015-06-01

    Full Text Available The emerging concept of successful aging is based on evidence that in healthy individual when they get aged, there are  considerable variations in physiological functions alteration. Some people exhibiting greater, but others very few or no age related alteration. The first is called poor aging and the later is called successful pattern of aging (Lambert SW, 2008. Thus, in the simple words the successful aging concept is define as an opportunity of old people to stay  active and productive condition despite they get aged chronologically. Aging itself might be defined as the progressive accumulation of changes with time associated with or responsible for the ever-increasing susceptibility to disease and death which accompanies advancing age (Harman D, 1981. The time needed to accumulate changes is attributable to aging process. The marked emerging questions are how does aging happen and where does aging start? To answer these questions and because of the complexity of aging process, there are more than 300 aging theories have been proposed to explain how and where aging occured and started respectively. There are too many to enumerate theories and classification of aging process. In summary, all of these aging theories can be grouped into three clusters: 1. Genetics program theory, this theory suggests that aging is resulted from program directed by the genes; 2. Epigenetic theory, in these theory aging is resulted from environmental random events not determined by the genes; 3. Evolutionary theory, which propose that aging is a medium for disposal mortal soma in order to avoid competition between organism and their progeny for food and space, did not try to explain how aging occur, but possibly answer why aging occur (De la Fuente. 2009. Among the three groups of aging theories, the epigenetic theory is useful to explain and try to solve the enigma of aging which is prominently caused by internal and external environmental influences

  2. Self-rated driving and driving safety in older adults.

    Science.gov (United States)

    Ross, Lesley A; Dodson, Joan E; Edwards, Jerri D; Ackerman, Michelle L; Ball, Karlene

    2012-09-01

    Many U.S. states rely on older adults to self-regulate their driving and determine when driving is no longer a safe option. However, the relationship of older adults' self-rated driving in terms of actual driving competency outcomes is unclear. The current study investigates self-rated driving in terms of (1) systematic differences between older adults with high (good/excellent) versus low (poor/fair/average) self-ratings, and (2) the predictive nature of self-rated driving to adverse driving outcomes in older adults (n=350; mean age 73.9, SD=5.25, range 65-91). Adverse driving outcomes included self-reported incidences of (1) being pulled over by the police, (2) receiving a citation, (3) receiving a recommendation to cease or limit driving, (4) crashes, and (5) state-reported crashes. Results found that older drivers with low self-ratings reported more medical conditions, less driving frequency, and had been given more suggestions to stop/limit their driving; there were no other significant differences between low and high self-raters. Logistic regression revealed older drivers were more likely to have a state-reported crash and receive a suggestion to stop or limit driving. Men were more likely to report all adverse driving outcomes except for receiving a suggestion to stop or limit driving. Regarding self-rated driving, older adults with high ratings were 66% less likely (OR=0.34, 95% CI=0.14-0.85) to have received suggestions to limit or stop driving after accounting for demographics, health and driving frequency. Self-ratings were not predictive of other driving outcomes (being pulled over by the police, receiving a citation, self-reported crashes, or state-reported crashes, ps>0.05). Most older drivers (85.14%) rated themselves as either good or excellent drivers regardless of their actual previous citation or crash rates. Self-rated driving is likely not related to actual driving proficiency as indicated by previous crash involvement in older adults

  3. Low Sex Drive in Women

    Science.gov (United States)

    Low sex drive in women Overview Women's sexual desires naturally fluctuate over the years. Highs and lows commonly coincide ... used for mood disorders also can cause low sex drive in women. If your lack of interest ...

  4. 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...

  5. Distracted Driving Raises Crash Risk

    Science.gov (United States)

    ... this issue Health Capsule Distracted Driving Raises Crash Risk En español Send us your comments Video technology ... distracted driving, especially among new drivers, raises the risk for car crashes and near crashes. The study ...

  6. Nuclear refueling platform drive system

    International Nuclear Information System (INIS)

    Busch, F.R.; Faulstich, D.L.

    1992-01-01

    This patent describes a drive system. It comprises: a gantry including a bridge having longitudinal and transverse axes and supported by spaced first and second end frames joined to fist and second end frames joined to first and second drive trucks for moving the bridge along the transverse axis; first means for driving the first drive truck; second means for driving the second drive truck being independent from the first driving means; and means for controlling the first and second driving means for reducing differential transverse travel between the first and second drive trucks, due to a skewing torque acting on the bridge, to less than a predetermined maximum, the controlling means being in the form of an electrical central processing unit and including: a closed-loop first velocity control means for controlling velocity of the first drive truck by providing a first command signal to the first driver means; a close loop second velocity control means for controlling velocity of the second drive truck by providing a second command signal to the second driving means; and an auxiliary closed-loop travel control means

  7. On Line Stator Resistance Tuning of DTC Control CSI Fed IM Drives

    OpenAIRE

    PANNEER SELVAM

    2012-01-01

    Current source inverter (CSI) fed drives are employed in high power applications. The conventional CSI drives suffer from drawbacks such as harmonic resonance, unstable operation at low speed ranges, and torque pulsation. CSI fed drives with Direct Torque Control (DTC) has drawn the attention of the motor drives designers because its implementation requires no position sensor. Crucial to the success of this scheme is the estimation of electromagnetic torque and stator flux linkages using the ...

  8. Variability of root traits in common bean genotypes at different levels of phosphorus supply and ontogenetic stages

    Directory of Open Access Journals (Sweden)

    Roberto dos Santos Trindade

    2014-08-01

    Full Text Available Selection of common bean (Phaseolus vulgaris L. cultivars with enhanced root growth would be a strategy for increasing P uptake and grain yield in tropical soils, but the strong plasticity of root traits may compromise their inclusion in breeding programs. The aim of this study was to evaluate the magnitude of the genotypic variability of root traits in common bean plants at two ontogenetic stages and two soil P levels. Twenty-four common bean genotypes, comprising the four growth habits that exist in the species and two wild genotypes, were grown in 4 kg pots at two levels of applied P (20 and 80 mg kg-1 and harvested at the stages of pod setting and early pod filling. Root area and root length were measured by digital image analysis. Significant genotype × P level and genotype × harvest interactions in analysis of variance indicate that the genotypic variation of root traits depended on soil nutrient availability and the stage at which evaluation was made. Genotypes differed for taproot mass, basal and lateral root mass, root area and root length at both P levels and growth stages; differences in specific root area and length were small. Genotypes with growth habits II (upright indeterminate and III (prostrate indeterminate showed better adaptation to limited P supply than genotypes of groups I (determinate and IV (indeterminate climbing. Between the two harvests, genotypes of groups II and III increased the mass of basal and lateral roots by 40 and 50 %, respectively, whereas genotypes of groups I and IV by only 7 and 19 %. Values of the genotypic coefficient of determination, which estimates the proportion of phenotypic variance resulting from genetic effects, were higher at early pod filling than at pod setting. Correlations between shoot mass and root mass, which could indicate indirect selection of root systems via aboveground biomass, were higher at early pod filling than at pod setting. The results indicate that selection for root

  9. Osteology, Phylogeny, Taphonomy, and Ontogenetic Histology of Oryctodromeus cubicularis, from the Middle Cretaceous (Albian-Cenomanian) of Montana and Idaho

    Science.gov (United States)

    Krumenacker, L. J.

    Oryctodromeus is a small bipedal dinosaur known from middle Cretaceous (95-100 My) Wayan Formation of Idaho and the Vaughn Member of the Blackleaf Formation of Montana. This taxon is hypothesized to be a burrowing dinosaur, which cared for its young within these burrows. This dissertation is a broad three-part treatment of this taxon, and excepting the introductory and concluding chapters this dissertation consists of three main chapters. Chapter two describes the osteology and phylogenetic relationships of this animal. Notable features of the Oryctodromeus skeleton described include a network of ossified tendons along the vertebral column that completely ensheath the tail, a long tail that forms more than half the length of the animal, and unusual femoral heads whose morphology may be related to burrowing behavior. The first full skeletal and skull reconstructions of this animal are presented. Chapter three investigates patterns of preservation of Oryctodromeus. Data suggests that preservation of single to multiple individuals of this taxon typically occurred in burrows that may be difficult to impossible to recognize in the fossil record. New examples of burrows from Oryctodromeus from the Vaughn and Wayan, as well as additional evidence for social behavior, are also described. A third chapter details the ontogenetic histology, growth rates and patterns of skeletal fusion based on seven limb elements (femora and tibiae) from different individuals. Based on the data in this dissertation, three growth stages can be recognized in Oryctodromeus based on bone histology. Juveniles are defined by more rapidly growing fibrolamellar tissue, sub-adults are defined by a cortex of inner fibrolamellar tissue and outer zonal parallel fibered tissue, and near-adult individuals have tissue similar to sub adults with dense avascular bone in the outermost cortex that signals a decrease in growth rate. LAG's suggest a minimum age of six to seven years for more mature individuals

  10. Diet-morphology relationship in the stream-dwelling characid Deuterodon stigmaturus (Gomes, 1947 (Characiformes: Characidae is partially conditioned by ontogenetic development

    Directory of Open Access Journals (Sweden)

    Renato Bolson Dala-Corte

    Full Text Available ABSTRACT We tested whether interindividual variations in diet composition within a population of Deuterodon stigmaturus can be explained by morphological differences between individuals, and whether diet-morphology relationships are dependent on the ontogenetic development. We analyzed diet of 75 specimens sampled in a coastal stream of Southern Brazil. Variation in stomach content was summarized with a Principal Coordinate Analysis (PCoA. The retained PCoA axes were tested as response to standard length (SL, and to values of intestine length (IL and mouth length (ML independent of body size, using linear mixed-effects models (LMM. The most consumed food items by D. stigmaturus were filamentous algae (41%, terrestrial plants (20.3%, detritus (12%, and aquatic invertebrates (8.8%. The LMMs showed that SL was positively related to consumption of terrestrial plants, whereas IL independent of SL was negatively related to aquatic invertebrates and positively related to filamentous algae. When body sized was held constant, ML was not related to diet variation. Interindividual diet differences conditioned to body size suggest that individuals shift their trophic niche and function in the ecosystem along the ontogenetic development. Relationships between intestine length and diet composition suggest interindividual differences in foraging ability and digestibility of distinct food items.

  11. Ontogenetic dietary shift and feeding strategy of Raja undulata Lacepède, 1802 (Chondrichthyes: Rajidae on the Portuguese continental shelf

    Directory of Open Access Journals (Sweden)

    Teresa Moura

    2008-06-01

    Full Text Available Under the scope of an ecosystem approach to fisheries, the understanding of trophic interactions is important for the assessment and consequently the proposal of suitable management measures. Raja undulata, like other rajids, is an important demersal predator in the Portuguese coastal community for which the biological and ecological information is still scarce. The ontogenetic dietary shift was investigated. Major length groups were defined through cluster analysis of the mean abundance of prey items. Prey diversity and feeding strategy were evaluated by length group. Multivariate analysis of variance was performed to test the influence of the factors sex, season and maturity on the diet of this species. It was concluded that R. undulata has a dietary ontogenetic shift within the definition of three major length groups (MLGs: 200-550 mm; 550-750 mm and 750-1000 mm. Diet varied from small and semi-pelagic to large and benthic prey. The feeding strategy of the species also changed from a generalised to a specialised diet. The decapod Polybius henslowi was the main prey item, especially for larger predators. Differences were found between sexes, maturity stages and seasons in each MLG.

  12. Immunohistochemical study on the ontogenetic development of the regional distribution of peptide YY, pancreatic polypeptide, and glucagon-like peptide 1 endocrine cells in bovine gastrointestinal tract.

    Science.gov (United States)

    Pyarokhil, Asadullah Hamid; Ishihara, Miyuki; Sasaki, Motoki; Kitamura, Nobuo

    2012-04-10

    The regional distribution and relative frequency of peptide YY (PYY)-, pancreatic polypeptide (PP)-, and glucagon-like peptide 1 (GLP-1)-immunoreactive (IR) cells were determined immunohistochemically in the gastrointestinal tract at seven ontogenetic stages in pre- and postnatal cattle. Different frequencies of PYY-, PP-, and GLP-1-IR cells were found in the intestines at all stages; they were not found in the esophagus and stomach. The frequencies varied depending on the intestinal segment and the developmental stage. The frequencies of PYY- and PP-IR cells were lower in the small intestine and increased from ileum to rectum, whereas GLP-1-IR cells were more numerous in duodenum and jejunum, decreased in ileum and cecum, and increased again in colon and rectum. The frequencies also varied according to pre- and postnatal stages. All three cell types were most numerous in fetus, and decreased in calf and adult groups, indicating that the frequencies of these three types of endocrine cells decrease with postnatal development. The results suggest that these changes vary depending on feeding habits and adaptation of growth, secretion, and motility of intestine at different ontogenetic stages of cattle. Copyright © 2011 Elsevier B.V. All rights reserved.

  13. Offset Compound Gear Drive

    Science.gov (United States)

    Stevens, Mark A.; Handschuh, Robert F.; Lewicki, David G.

    2010-01-01

    The Offset Compound Gear Drive is an in-line, discrete, two-speed device utilizing a special offset compound gear that has both an internal tooth configuration on the input end and external tooth configuration on the output end, thus allowing it to mesh in series, simultaneously, with both a smaller external tooth input gear and a larger internal tooth output gear. This unique geometry and offset axis permits the compound gear to mesh with the smaller diameter input gear and the larger diameter output gear, both of which are on the same central, or primary, centerline. This configuration results in a compact in-line reduction gear set consisting of fewer gears and bearings than a conventional planetary gear train. Switching between the two output ratios is accomplished through a main control clutch and sprag. Power flow to the above is transmitted through concentric power paths. Low-speed operation is accomplished in two meshes. For the purpose of illustrating the low-speed output operation, the following example pitch diameters are given. A 5.0 pitch diameter (PD) input gear to 7.50 PD (internal tooth) intermediate gear (0.667 reduction mesh), and a 7.50 PD (external tooth) intermediate gear to a 10.00 PD output gear (0.750 reduction mesh). Note that it is not required that the intermediate gears on the offset axis be of the same diameter. For this example, the resultant low-speed ratio is 2:1 (output speed = 0.500; product of stage one 0.667 reduction and stage two 0.750 stage reduction). The design is not restricted to the example pitch diameters, or output ratio. From the output gear, power is transmitted through a hollow drive shaft, which, in turn, drives a sprag during which time the main clutch is disengaged.

  14. Electrical machines & drives

    CERN Document Server

    Hammond, P

    1985-01-01

    Containing approximately 200 problems (100 worked), the text covers a wide range of topics concerning electrical machines, placing particular emphasis upon electrical-machine drive applications. The theory is concisely reviewed and focuses on features common to all machine types. The problems are arranged in order of increasing levels of complexity and discussions of the solutions are included where appropriate to illustrate the engineering implications. This second edition includes an important new chapter on mathematical and computer simulation of machine systems and revised discussions o

  15. Measurement of Driving Terms

    CERN Document Server

    Schmidt, F; Faus-Golfe, A

    2001-01-01

    In 2000 a series of MDs has been performed at the SPS to measure resonance driving terms. Theory predicts that these terms can be determined by harmonic analysis of BPM data recorded after applying single kicks at various amplitudes. Strong sextupoles were introduced to create a sizeable amount of nonlinearities. Experiments at injection energy (26 GeV) with single bunch as well as one experiment at 120 GeV with 84 bunches were carried out. The expected nonlinear content is compared to the experimenteal observation.

  16. 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.

  17. Parkinson's disease and driving ability

    Science.gov (United States)

    Singh, Rajiv; Pentland, Brian; Hunter, John; Provan, Frances

    2007-01-01

    Objectives To explore the driving problems associated with Parkinson's disease (PD) and to ascertain whether any clinical features or tests predict driver safety. Methods The driving ability of 154 individuals with PD referred to a driving assessment centre was determined by a combination of clinical tests, reaction times on a test rig and an in‐car driving test. Results The majority of cases (104, 66%) were able to continue driving although 46 individuals required an automatic transmission and 10 others needed car modifications. Ability to drive was predicted by the severity of physical disease, age, presence of other associated medical conditions, particularly dementia, duration of disease, brake reaction, time on a test rig and score on a driving test (all pautomatic transmission. A combination of clinical tests and in‐car driving assessment will establish safety to drive, and a number of clinical correlates can be shown to predict the likely outcome and may assist in the decision process. This is the largest series of consecutive patients seen at a driving assessment centre reported to date, and the first to devise a scoring system for on‐road driving assessment. PMID:17178820

  18. Glaucoma and Driving: On-Road Driving Characteristics

    Science.gov (United States)

    Wood, Joanne M.; Black, Alex A.; Mallon, Kerry; Thomas, Ravi; Owsley, Cynthia

    2016-01-01

    Purpose To comprehensively investigate the types of driving errors and locations that are most problematic for older drivers with glaucoma compared to those without glaucoma using a standardized on-road assessment. Methods Participants included 75 drivers with glaucoma (mean = 73.2±6.0 years) with mild to moderate field loss (better-eye MD = -1.21 dB; worse-eye MD = -7.75 dB) and 70 age-matched controls without glaucoma (mean = 72.6 ± 5.0 years). On-road driving performance was assessed in a dual-brake vehicle by an occupational therapist using a standardized scoring system which assessed the types of driving errors and the locations where they were made and the number of critical errors that required an instructor intervention. Driving safety was rated on a 10-point scale. Self-reported driving ability and difficulties were recorded using the Driving Habits Questionnaire. Results Drivers with glaucoma were rated as significantly less safe, made more driving errors, and had almost double the rate of critical errors than those without glaucoma. Driving errors involved lane positioning and planning/approach, and were significantly more likely to occur at traffic lights and yield/give-way intersections. There were few between group differences in self-reported driving ability. Conclusions Older drivers with glaucoma with even mild to moderate field loss exhibit impairments in driving ability, particularly during complex driving situations that involve tactical problems with lane-position, planning ahead and observation. These results, together with the fact that these drivers self-report their driving to be relatively good, reinforce the need for evidence-based on-road assessments for evaluating driving fitness. PMID:27472221

  19. A qualitative exploration of driving stress and driving discourtesy.

    Science.gov (United States)

    Scott-Parker, B; Jones, C M; Rune, K; Tucker, J

    2018-05-31

    Driving courtesy, and conversely driving discourtesy, recently has been of great interest in the public domain. In addition, there has been increasing recognition of the negative impact of stress upon the individual's health and wellbeing, with a plethora of interventions aimed at minimising stress more generally. The research literature regarding driving dis/courtesy, in comparison, is scant, with a handful of studies examining the dis/courteous driving behaviour of road users, and the relationship between driving discourtesy and driving stress. To examine courteous and discourteous driving experiences, and to explore the impact of stress associated with such driving experiences. Thirty-eight drivers (20 females) from the Sunshine Coast region volunteered to participate in one of four 1-1.5 h focus groups. Content analysis used the verbatim utterances captured via an Mp3 device. Three themes pertaining to stressful and discourteous interactions were identified. Theme one pertained to the driving context: road infrastructure (eg, roundabouts, roadwork), vehicles (eg, features), location (eg, country vs city, unfamiliar areas), and temporal aspects (eg, holidays). Theme two pertained to other road users: their behaviour (eg, tailgating, merging), and unknown factors (eg, illicit and licit drug use). Theme three pertained to the self as road user: their own behaviours (eg, deliberate intimidation), and their emotions (eg, angry reaction to other drivers, being in control). Driving dis/courtesy and driving stress is a complex phenomenon, suggesting complex intervention efforts are required. Driving discourtesy was reported as being highly stressful, therefore intervention efforts which encourage driving courtesy and which foster emotional capacity to cope with stressful circumstances appear warranted. Copyright © 2018. Published by Elsevier Ltd.

  20. Glaucoma and Driving: On-Road Driving Characteristics.

    Directory of Open Access Journals (Sweden)

    Joanne M Wood

    Full Text Available To comprehensively investigate the types of driving errors and locations that are most problematic for older drivers with glaucoma compared to those without glaucoma using a standardized on-road assessment.Participants included 75 drivers with glaucoma (mean = 73.2±6.0 years with mild to moderate field loss (better-eye MD = -1.21 dB; worse-eye MD = -7.75 dB and 70 age-matched controls without glaucoma (mean = 72.6 ± 5.0 years. On-road driving performance was assessed in a dual-brake vehicle by an occupational therapist using a standardized scoring system which assessed the types of driving errors and the locations where they were made and the number of critical errors that required an instructor intervention. Driving safety was rated on a 10-point scale. Self-reported driving ability and difficulties were recorded using the Driving Habits Questionnaire.Drivers with glaucoma were rated as significantly less safe, made more driving errors, and had almost double the rate of critical errors than those without glaucoma. Driving errors involved lane positioning and planning/approach, and were significantly more likely to occur at traffic lights and yield/give-way intersections. There were few between group differences in self-reported driving ability.Older drivers with glaucoma with even mild to moderate field loss exhibit impairments in driving ability, particularly during complex driving situations that involve tactical problems with lane-position, planning ahead and observation. These results, together with the fact that these drivers self-report their driving to be relatively good, reinforce the need for evidence-based on-road assessments for evaluating driving fitness.

  1. Glaucoma and Driving: On-Road Driving Characteristics.

    Science.gov (United States)

    Wood, Joanne M; Black, Alex A; Mallon, Kerry; Thomas, Ravi; Owsley, Cynthia

    2016-01-01

    To comprehensively investigate the types of driving errors and locations that are most problematic for older drivers with glaucoma compared to those without glaucoma using a standardized on-road assessment. Participants included 75 drivers with glaucoma (mean = 73.2±6.0 years) with mild to moderate field loss (better-eye MD = -1.21 dB; worse-eye MD = -7.75 dB) and 70 age-matched controls without glaucoma (mean = 72.6 ± 5.0 years). On-road driving performance was assessed in a dual-brake vehicle by an occupational therapist using a standardized scoring system which assessed the types of driving errors and the locations where they were made and the number of critical errors that required an instructor intervention. Driving safety was rated on a 10-point scale. Self-reported driving ability and difficulties were recorded using the Driving Habits Questionnaire. Drivers with glaucoma were rated as significantly less safe, made more driving errors, and had almost double the rate of critical errors than those without glaucoma. Driving errors involved lane positioning and planning/approach, and were significantly more likely to occur at traffic lights and yield/give-way intersections. There were few between group differences in self-reported driving ability. Older drivers with glaucoma with even mild to moderate field loss exhibit impairments in driving ability, particularly during complex driving situations that involve tactical problems with lane-position, planning ahead and observation. These results, together with the fact that these drivers self-report their driving to be relatively good, reinforce the need for evidence-based on-road assessments for evaluating driving fitness.

  2. Control rod drives

    International Nuclear Information System (INIS)

    Hayakawa, Hiroyasu; Kawamura, Atsuo.

    1979-01-01

    Purpose: To reduce pellet-clad mechanical interactions, as well as improve the fuel safety. Constitution: In the rod drive of a bwr type reactor, an electric motor operated upon intermittent input such as of pulse signals is connected to a control rod. A resolver for converting the rotational angle of the motor to electric signals is connected to the rotational shaft of the motor and the phase difference between the output signal from the resolver and a reference signal is adapted to detect by a comparator. Based on the detection result, the controller is actuated to control a motor for control rod drive so that fine control for the movement of the control rod is made possible. This can reduce the moving distance of the control rod, decrease the thermal stress applied to the control rod and decrease the pellet clad mechanical interaction failures due to thermal expansion between the cladding tube and the pellets caused by abrupt changes in the generated power. (Furukawa, Y.)

  3. Control rod drives

    International Nuclear Information System (INIS)

    Oonuki, Koji.

    1981-01-01

    Purpose: To increase the driving speed of control rods at rapid insertion with an elongate control rod and an extension pipe while ensuring sufficient buffering performance in a short buffering distance, by providing a plurality of buffers to an extension pipe between a control rod drive source and a control rod in LMFBR type reactor. Constitution: First, second and third buffers are respectively provided to an acceleration piston, an extension pipe and a control rod respectively and the insertion positions for each of the buffers are displaced orderly from above to below. Upon disconnection of energizing current for an electromagnet, the acceleration piston, the extension pipe and the control rod are rapidly inserted in one body. The first, second and third buffers are respectively actuated at each of their falling strokes upon rapid insertion respectively, and the acceleration piston, the extension pipe and the control rod receive the deceleration effect in the order correspondingly. Although the compression force is applied to the control rod only near the stroke end, it does not cause deformation. (Kawakami, Y.)

  4. Correlates of Marijuana Drugged Driving and Openness to Driving While High: Evidence from Colorado and Washington.

    Directory of Open Access Journals (Sweden)

    Kevin C Davis

    with lower odds of each of these outcomes (OR = 0.63, P < 0.01, OR = 0.69, P = 0.02, respectively. Post-estimation Wald tests confirmed the negative associations with marijuana DUI were greater in magnitude for safety perceptions than knowledge of DUI laws. Increased perceptions that driving while high is unsafe was associated with significantly lower willingness to drive after using marijuana while increased knowledge of marijuana DUI laws was not associated with these outcomes.Despite recent interventions targeting public awareness of the legal consequences of marijuana DUI, our results suggest that knowledge of these laws is a weaker predictor of DUI behavior than perceptions that driving high is unsafe. In addition, safety perceptions predict decreased openness to driving high while knowledge of DUI laws was not associated with openness. These findings suggest that interventions for reducing the incidence of marijuana DUI are likely to be more successful by targeting safety perceptions related to marijuana DUI rather than knowledge of DUI laws. We caution that because these data are limited to an online convenience sample, results may not be generalizable beyond our sample.

  5. 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.

  6. [Epilepsy and driving].

    Science.gov (United States)

    Matsuura, Masato

    2014-05-01

    In Japan, the Road Traffic Act was amended in June 2013, including new penalty to false statement in a disease condition declaration form, and new voluntary notification system for a doctor who is aware that a person is at high risk for traffic accident and in possession of a driver license. Moreover, New Criminal Law Act was established in November 2013, including a prison sentence of up to 15 years for persons, who under the influence of specific drugs or diseases, causing death or injury to other persons by driving a motor vehicle. Both laws are supposed to be enforced during 2014, after additional resolutions including the review of the laws after five years, considerations so as not to create discrimination due to diseases, etc are examined.

  7. Control rod drives

    International Nuclear Information System (INIS)

    Furumitsu, Yutaka.

    1981-01-01

    Purpose: To improve the reliability of a device for driving an LMFBR type reactor control rod by providing a buffer unit having a stationary electromagnetic coil and a movable electromagnetic coil in the device to thereby avord impact stress at scram time and to simplify the structure of the buffer unit. Constitution: A non-contact type buffer unit is constructed with a stationary electromagnetic coil, a cable for the stationary coil, a movable electromagnetic coil, a spring cable for the movable coil, and a backup coil spring or the like. Force produced at scram time is delivered without impact by the attracting or repelling force between the stationary coil and the movable coil of the buffer unit. Accordingly, since the buffer unit is of a non-contact type, there is no mechanical impact and thus no large impact stress, and as it has simple configuration, the reliability is improved and the maintenance can be conducted more easily. (Yoshihara, H.)

  8. Control rod drives

    International Nuclear Information System (INIS)

    Yamanaka, Toshikatsu.

    1979-01-01

    Purpose: To protect bellows against failures due to negative pressure to prevent the loss of pressure balance caused by the expansion of the bellows upon scram. Constitution: An expansion pipe connected to the control rod drive is driven along a guide pipe to insert a control rod into the reactor core. Expansible bellows are provided at the step between the expansion pipe and the guide pipe. Further, a plurality of bore holes or slits are formed on the side wall of the guide pipe corresponding to the expansion portion of the bellows. In such an arrangement, when the expansion pipe falls rapidly and the bellows are expanded upon scram, the volume between each of the pipes of the bellows and the guide pipe is increased to produce a negative pressure, but the effect of the negative pressure on the bellows can be eliminated by the flowing-in of coolants corresponding to that pressure through the bore holes or the slits. (Furukawa, Y.)

  9. Do emotions drive psychosis?

    Directory of Open Access Journals (Sweden)

    João G. Ribeiro

    2012-12-01

    Full Text Available Introduction: How important is the emotional life of persons who manifest psychotic symptoms? Aims: The aim of this paper is to review evidence on a causal role for emotions in psychotic processes. Methods: Selective review of literature on affective symptoms in psychoses, on emotions in the production of psychotic symptoms and on dopaminergic models of psychosis. Results: Affective symptoms are relevant across psychoses. Persons with schizophrenia have high levels of emotional reactivity and the intensification of negative affects not only is associated with but also precedes the intensification of psychotic symptoms, which is evidence that negative emotions drive the course of psychotic symptoms. Negative self‑representations are central in psychotic processes and can be the link between negative emotions and psychosis. Evidence favours the notion that persecutory delusions are consistent with negative affects and self‑representations, while grandiose delusions are consistent with a defensive amplification of positive affects and self‑representations. Shame has been proposed as the core emotional experience of psychosis, one in which the self becomes vulnerable to the external world, which is consistent with persecutory experiences. Assaults on the self, under the form of hostility in the family environment and society, are strong predictors of relapse and development of schizophrenia. Assaults on the self which induce social defeat are also strong stimulants of mesolimbic dopaminergic pathways, whose hyperactivity is associated with acute psychotic episodes and the experience of “aberrant salience”, put forward as a dopaminergic model of psychosis. Conclusions: The “defeat of the self” emerges as a central link that binds the experience of negative emotions to the expression of psychotic symptoms and its psychological and neurobiological correlates. The hypothesis gains support that the emotions related to that defeat control

  10. CLIC Drive Beam Phase Stabilisation

    CERN Document Server

    Gerbershagen, Alexander; Schulte, Daniel

    The thesis presents phase stability studies for the Compact Linear Collider (CLIC) and focuses in particular on CLIC Drive Beam longitudinal phase stabilisation. This topic constitutes one of the main feasibility challenges for CLIC construction and is an essential component of the current CLIC stabilisation campaign. The studies are divided into two large interrelated sections: the simulation studies for the CLIC Drive Beam stability, and measurements, data analysis and simulations of the CLIC Test Facility (CTF3) Drive Beam phase errors. A dedicated software tool has been developed for a step-by-step analysis of the error propagation through the CLIC Drive Beam. It uses realistic RF potential and beam loading amplitude functions for the Drive and Main Beam accelerating structures, complete models of the recombination scheme and compressor chicane as well as of further CLIC Drive Beam modules. The tool has been tested extensively and its functionality has been verified. The phase error propagation at CLIC h...

  11. 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.

  12. Failure Prediction for Autonomous Driving

    OpenAIRE

    Hecker, Simon; Dai, Dengxin; Van Gool, Luc

    2018-01-01

    The primary focus of autonomous driving research is to improve driving accuracy. While great progress has been made, state-of-the-art algorithms still fail at times. Such failures may have catastrophic consequences. It therefore is important that automated cars foresee problems ahead as early as possible. This is also of paramount importance if the driver will be asked to take over. We conjecture that failures do not occur randomly. For instance, driving models may fail more likely at places ...

  13. The Drive-Wise Project: Driving Simulator Training increases real driving performance in healthy older drivers

    Directory of Open Access Journals (Sweden)

    Gianclaudio eCasutt

    2014-05-01

    Full Text Available Background: Age-related cognitive decline is often associated with unsafe driving behavior. We hypothesized that 10 active training sessions in a driving simulator increase cognitive and on-road driving performance. In addition, driving simulator training should outperform cognitive training.Methods: Ninety-one healthy active drivers (62 – 87 years were randomly assigned to either (1 a driving simulator training group, (2 an attention training group (vigilance and selective attention, or (3 a control group. The main outcome variables were on-road driving and cognitive performance. Seventy-seven participants (85% completed the training and were included in the analyses. Training gains were analyzed using a multiple regression analysis with planned comparisons.Results: The driving simulator training group showed an improvement in on-road driving performance compared to the attention training group. In addition, both training groups increased cognitive performance compared to the control group. Conclusion: Driving simulator training offers the potential to enhance driving skills in older drivers. Compared to the attention training, the simulator training seems to be a more powerful program for increasing older drivers’ safety on the road.

  14. Noninductive current drive in tokamaks

    International Nuclear Information System (INIS)

    Uckan, N.A.

    1985-01-01

    Various current drive mechanisms may be grouped into four classes: (1) injection of energetic particle beams; (2) launching of rf waves; (3) hybrid schemes, which are combinations of various rf schemes (rf plus beams, rf and/or beam plus ohmic heating, etc.); and (4) other schemes, some of which are specific to reactor plasma conditions requiring the presence of alpha particle or intense synchrotron radiation. Particle injection schemes include current drive by neutral beams and relativistic electron beams. The rf schemes include current drive by the lower hybrid (LH) waves, the electron waves, the waves in the ion cyclotron range of frequencies, etc. Only a few of these approaches, however, have been tested experimentally, with the broadest data base available for LH waves. Included in this report are (1) efficiency criteria for current drive, (2) current drive by neutral beam injection, (3) LH current drive, (4) electron cyclotron current drive, (5) current drive by ion cyclotron waves - minority species heating, and (6) current drive by other schemes (such as hybrids and low frequency waves)

  15. Electric motor drive unit, especially adjustment drive for vehicles

    Energy Technology Data Exchange (ETDEWEB)

    Litterst, P

    1980-05-29

    An electric motor drive unit, particularly an adjustment drive for vehicles with at least two parallel drive shafts is described, which is compact and saves space, and whose manufacturing costs are low compared with those of well-known drive units of this type. The drive unit contains a suitable number of magnet systems, preferably permanent magnet systems, whose pole axes are spaced and run parallel. The two pole magnet systems have diametrically opposite shell-shaped segments, to which the poles are fixed. In at least one magnet system the two segments are connected by diametrically opposite flat walls parallel to the pole axes to form a single magnetic circuit pole housing. The segments of at least one other magnet system are arranged on this pole housing so that one of these flat walls is a magnetically conducting, connecting component of the magnetic circuit of the other magnet system.

  16. Ensuring a successful family business management succession

    OpenAIRE

    Desbois, Joris

    2016-01-01

    Succession is the biggest long-term challenge that most family businesses face. Indeed, leaders ‘disposition to plan for their succession is frequently the key factor defining whether their family business subsists or stops. The research seeks to find out how to manage successfully the business management succession over main principles. This work project aims at researching the key points relevant to almost all family firms, to have a viable succession transition and positioni...

  17. Control rod drives

    International Nuclear Information System (INIS)

    Ikakura, Hiroaki.

    1986-01-01

    Purpose: To enable to direct disconnection of control rods upon abnormal temperature rise in the reactor thereby improve the reliability for the disconnecting operation in control rod drives for FBR type reactors upon emergency. Constitution: A diaphragm is disposed to the upper opening of a sealing vessel inserted to the hollow portion of an electromagnet and a rod is secured to the central position of the upper surface. A spring contacts are attached by way of an insulator to the inner surface at the lower portion of an extension pipe and connected with cables for supplying electric power sources respectively to a magnet. If the temperature in the reactor abnormally rises, liquid metals in the sealing vessel are expanded tending to extend the bellows downwardly. However, since they are attracted by the electromagnet, the thermal expansion of the liquid metals exert on the diaphragm prior to the bellows. Thus, the switch between the spring contacts is made open to attain the deenergized state to thereby disconnect the control rod and shutdown the neclear reactor. (Horiuchi, T.)

  18. Driving for shorter outages

    International Nuclear Information System (INIS)

    Tritch, S.

    1996-01-01

    Nuclear plant outages are necessary to complete activities that cannot be completed during the operating cycle, such as steam generator inspection and testing, refueling, installing modifications, and performing maintenance tests. The time devoted to performing outages is normally the largest contributor to plant unavailability. Similarly, outage costs are a sizable portion of the total plant budget. The scope and quality of work done during outages directly affects operating reliability and the number of unplanned outages. Improved management and planning of outages enhances the margin of safety during the outage and results in increased plant reliability. The detailed planning and in-depth preparation that has become a necessity for driving shorter outage durations has also produced safer outages and improved post-outage reliability. Short outages require both plant and vendor management to focus on all aspects of the outage. Short outage durations, such as 26 days at South Texas or 29 days at North Anna, require power plant inter-department and intra-department teamwork and communication and vendor participation. In this paper shorter and safer outage at the 3-loop plants in the United States are explained. (J.P.N.)

  19. Control rod drive

    International Nuclear Information System (INIS)

    Kojima, Akira.

    1989-01-01

    In the control rod drive for a BWR type reactor, etc., according to this invention, the lower limit flow rate is set so as to keep the restriction for stability upon spectral shift operation. The setting condition for keeping the restriction is the lowest pump speed and the lower limit for the automatic control of the flow rate, which are considered to be important in view of the stablility from the actual power state. In view of the above, it is possible to keep the reactor core stably even in a case where such a transient phenomenon occurs that the recycling flow rate has to be run back to the lowest pump speed during spectral shift opeeration or in a case where the load demand is reduced and the flow rate is decreased by an automatic mode as in night operation. Accordingly, in the case of conducting the spectral shift operation according to this invention, the operation region capable of keeping the reactor core state stably during operation can be extended. (I.S.)

  20. Snake venomics across genus Lachesis. Ontogenetic changes in the venom composition of Lachesis stenophrys and comparative proteomics of the venoms of adult Lachesis melanocephala and Lachesis acrochorda.

    Science.gov (United States)

    Madrigal, Marvin; Sanz, Libia; Flores-Díaz, Marietta; Sasa, Mahmood; Núñez, Vitelbina; Alape-Girón, Alberto; Calvete, Juan J

    2012-12-21

    We report the proteomic analysis of ontogenetic changes in venom composition of the Central American bushmaster, Lachesis stenophrys, and the characterization of the venom proteomes of two congeneric pitvipers, Lachesis melanocephala (black-headed bushmaster) and Lachesis acrochorda (Chochoan bushmaster). Along with the previous characterization of the venom proteome of Lachesis muta muta (from Bolivia), our present outcome enables a comparative overview of the composition and distribution of the toxic proteins across genus Lachesis. Comparative venomics revealed the close kinship of Central American L. stenophrys and L. melanocephala and support the elevation of L. acrochorda to species status. Major ontogenetic changes in the toxin composition of L. stenophrys venom involves quantitative changes in the concentration of vasoactive peptides and serine proteinases, which steadily decrease from birth to adulthood, and age-dependent de novo biosynthesis of Gal-lectin and snake venom metalloproteinases (SVMPs). The net result is a shift from a bradykinin-potentiating and C-type natriuretic peptide (BPP/C-NP)-rich and serine proteinase-rich venom in newborns and 2-years-old juveniles to a (PI>PIII) SVMP-rich venom in adults. Notwithstanding minor qualitative and quantitative differences, the venom arsenals of L. melanocephala and L. acrochorda are broadly similar between themselves and also closely mirror those of adult L. stenophrys and L. muta venoms. The high conservation of the overall composition of Central and South American bushmaster venoms provides the ground for rationalizing the "Lachesis syndrome", characterized by vagal syntomatology, sensorial disorders, hematologic, and cardiovascular manifestations, documented in envenomings by different species of this wide-ranging genus. This finding let us predict that monospecific Lachesic antivenoms may exhibit paraspecificity against all congeneric species. Copyright © 2012 Elsevier B.V. All rights reserved.

  1. Differential ontogenetic patterns of levocabastine-sensitive neurotensin NT2 receptors and of NT1 receptors in the rat brain revealed by in situ hybridization.

    Science.gov (United States)

    Lépée-Lorgeoux, I; Betancur, C; Rostène, W; Pélaprat, D

    1999-03-12

    The postnatal ontogeny of the levocabastine-sensitive neurotensin receptor (NT2) mRNA was studied by in situ hybridization in the rat brain and compared with the distribution of the levocabastine-insensitive NT1 receptor. NT2 receptor mRNA was absent at birth from all brain structures except the ependymal cell layer lining the ventricles. The development of NT2 receptor mRNA followed three ontogenetic patterns. The first pattern, involving the majority of the cerebral gray matter, was characterized by a continuous increase from postnatal day 5 (P5) to P30. The second one, involving regions rich in myelinated fibers such as the corpus callosum and lacunosum moleculare layer of the hippocampus, exhibited a pronounced increase between P5 and P10, peaked at P15 and was followed by a plateau or a slight decrease. The third pattern was observed in the ependymal cell layer lining the olfactory and lateral ventricles, where the high labeling already present at birth continued to increase during development. These different developmental patterns could reflect the variety of cells expressing NT2 receptor mRNA, including neurons, protoplasmic astrocytes in gray matter, fibrous astrocytes present in myelinated fibers tracts, and ependymal cells. In contrast, NT1 receptor mRNA, which seems to be associated only with neurons, was highly and transiently expressed during the perinatal period in the cerebral cortex, hippocampus and striatal neuroepithelium. Other regions, notably the ventral tegmental area and substantia nigra compacta, exhibited a gradual increase in NT1 receptor signal, reaching adult levels by P21. Both the differential localization and ontogenetic profiles of NT1 and NT2 receptor mRNAs suggest different involvement of these two receptors in brain functions and development. Copyright 1999 Elsevier Science B.V.

  2. Ontogenetic changes and developmental adjustments in lactate dehydrogenase isozymes of an obligate air-breathing fish Channa punctatus during deprivation of air access.

    Science.gov (United States)

    Ahmad, Riaz; Hasnain, Absar-Ul

    2005-02-01

    In air-breathing snakehead Channa punctatus, Ldh-B is expressed at all ontogenetic and developmental stages, while Ldh-A is expressed temporally in pre-hatchlings 12-13 days ahead of bimodal respiration marked by air-breathing. Remarkable differences are observed in the LDH isozyme expression among various ontogenetic and developmental stages upon denying air access. When denied air access, water-breathing larvae show two distinct characteristics: (i) they survive longer than transitory air-breathers due to independence from air-breathing and (ii) there is more transient induction of Ldh-B than Ldh-A. Transition to bimodal breathing, which occurred post-hatching in 15-day old larvae, is coincidental with inducibility of Ldh-A and concomitant down-regulation of Ldh-B. Heart tissue from air-breathing adults denied air access shows a preferential expression of LDH-A subunit and slight down-regulation of LDH-B. Heterotetramers of A and B subunits participate in adjusting LDH levels among those stages which either precede air-breathing switchover, or are subsequent to this transition. The contribution of heterotetramers depends on the stage-specific levels of LDH homotetramers A(4) or B(4). Scaling of muscle mass during growth, tolerance to extended deprivation of air access and induction of Ldh-A are correlated. Response to restoring air contact indicated that advanced air-breathing stages of C. punctatus possess an inherent capacity to sense surface air. In kinetic properties, LDH isozymes of C. punctatus are teleost-like but species specificity is displayed in oxidative potential by cardiac muscle and in L-lactate reduction by skeletal muscle.

  3. Ontogenetic improvement of visual function in the medaka Oryzias latipes based on an optomotor testing system for larval and adult fish

    Science.gov (United States)

    Carvalho, Paulo S. M.; Noltie, Douglas B.; Tillitt, D.E.

    2002-01-01

    We developed a system for evaluation of visual function in larval and adult fish. Both optomotor (swimming) and optokinetic (eye movement) responses were monitored and recorded using a system of rotating stripes. The system allowed manipulation of factors such as width of the stripes used, rotation speed of the striped drum, and light illuminance levels within both the scotopic and photopic ranges. Precise control of these factors allowed quantitative measurements of visual acuity and motion detection. Using this apparatus, we tested the hypothesis that significant posthatch ontogenetic improvements in visual function occur in the medaka Oryzias latipes, and also that this species shows significant in ovo neuronal development. Significant improvements in the acuity angle alpha (ability to discriminate detail) were observed from approximately 5 degrees at hatch to 1 degree in the oldest adult stages. In addition, we measured a significant improvement in flicker fusion thresholds (motion detection skills) between larval and adult life stages within both the scotopic and photopic ranges of light illuminance. Ranges of flicker fusion thresholds (X±SD) at log I=1.96 (photopic) varied from 37.2±1.6 cycles/s in young adults to 18.6±1.6 cycles/s in young larvae 10 days posthatch. At log I=−2.54 (scotopic), flicker fusion thresholds varied from 5.8±0.7 cycles/s in young adults to 1.7±0.4 cycles/s in young larvae 10 days posthatch. Light sensitivity increased approximately 2.9 log units from early hatched larval stages to adults. The demonstrated ontogenetic improvements in visual function probably enable the fish to explore new resources, thereby enlarging their fundamental niche.

  4. Ontogenetic, spatial and temporal variations in the feeding ecology of Deuterodon langei Travassos, 1957 (Teleostei: Characidae in a Neotropical stream from the Atlantic rainforest, southern Brazil

    Directory of Open Access Journals (Sweden)

    Jean R. S. Vitule

    Full Text Available Information related to the diet of one species always contributes to the knowledge of its bionomy and the functioning of the ecosystem in which the species lives. Therefore, understanding the feeding ecology of one fish population and its ontogenetic, spatial and temporal aspects help to understand the structure of fish assemblages and river communities. Knowledge of this structure is essential for habitat management and biodiversity conservation. The feeding ecology of Deuterodon langei Travassos, 1957 was studied through analyses of diet composition, sharing of resources, feeding strategy and contribution of food items to the width of its niche. The analysis included an assessment of ontogenetic, spatial and seasonal variations. The species was considered omnivorous with great plasticity caused by seasonal variation in food availability throughout the river basin, but mainly through ontogeny. The diet of smaller individuals revealed a predominance of insects and other arthropods, while the diet of larger specimens showed allochthonous plant items as the main components. The low intestinal quotient (IQ values for the smaller individuals were accounted for their mainly insectivorous diet. The greater relative length of the intestine can account for the greater plasticity of the adult diet, enabling them to use diet items of larger size and more difficult digestion, such as plant items. Therefore, shifts in feeding ecology during growth are confirmed in this omnivorous tropical river fish, strengthening the concept that, when comparing food habits among species, fish size must be taken into account. This study also provides needed information regarding the feeding ecology of fishes intrinsically associated with the Atlantic rainforest, one of the most threatened and biodiverse ecosystems of the planet.

  5. Control rod drive shaft latch

    International Nuclear Information System (INIS)

    Thorp, A.G. II.

    1976-01-01

    A latch mechanism is operated by differential pressure on a piston to engage the drive shaft for a control rod in a nuclear reactor, thereby preventing the control rod from being ejected from the reactor in case of failure of the control rod drive mechanism housing which is subjected to the internal pressure in the reactor vessel. 6 claims, 4 drawing figures

  6. ECO-DRIVING MODELING ENVIRONMENT

    Science.gov (United States)

    2015-11-01

    This research project aims to examine the eco-driving modeling capabilities of different traffic modeling tools available and to develop a driver-simulator-based eco-driving modeling tool to evaluate driver behavior and to reliably estimate or measur...

  7. Real-world driving behaviour

    NARCIS (Netherlands)

    Rijkeboer, R.C.; Hendriksen, P.; Gense, N.L.J.

    2001-01-01

    With increasing complexity of engine management system there is a tendency for traditional driving cyles to become further and further removed from reality. So for a sensible evaluation of emissions and fuel consumption of road vehicles in the field there is an urgent need for 'real-world' driving

  8. H1 antihistamines and driving

    OpenAIRE

    Florin-Dan, Popescu

    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...

  9. [Driving and health at work].

    Science.gov (United States)

    Giorgio, Marie-Thérèse

    2015-09-01

    The role of the occupational physician is to prevent occupational accidents and diseases. Therefore, he is the one to decide if a worker is fit to drive in the context of his professional activity, including in cases where no specific driving license is required (e.g. forklift truck, mobile crane). This decision is an important one, as two thirds of fatal occupational accidents occur on the road. The decision is made on the basis of both a medical examination and the regulation, which indicates all contraindications to driving. The physician's responsibility is involved, as is the employer's, as he must ensure that his employee is fit to drive and possesses a valid driving license at all times. Copyright © 2015 Elsevier Masson SAS. All rights reserved.

  10. Proceedings of the driving safety technology forum

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2006-07-01

    This one day forum focused on improving driving safety in the petroleum industry by introducing new technologies and strategies. The forum featured several keynote addresses on driving safety as well as the Government of Alberta's Tactical Plan and Alberta Road Safety at Work Strategy. Presentations consisted of success stories of new technology or process applications or proposed technology demonstration projects followed by question and answer panels around the following topics: industry and government strategies; driver fatigue management and prevention; driver behaviour and culture change; vehicle monitoring systems and innovative wildlife avoidance techniques. Specific presentations addressed BP's driving safety strategy, in-cabin air quality and truck drivers' health and safety and how Talisman Energy implemented oilfield fleet safety using event driven automated vehicle location technologies. A total of 3 keynote addresses, 3 panel question and answer sessions and 11 presentations were presented at the conference, of which 3 have been catalogued separately for inclusion in this database. refs., tabs., figs.

  11. CTF3 Drive Beam Injector Optimisation

    CERN Document Server

    AUTHOR|(CDS)2082899; Doebert, S

    2015-01-01

    In the Compact Linear Collider (CLIC) the RF power for the acceleration of the Main Beam is extracted from a high-current Drive Beam that runs parallel to the main linac. The main feasibility issues of the two-beam acceleration scheme are being demonstrated at CLIC Test Facility 3 (CTF3). The CTF3 Drive Beam injector consists of a thermionic gun followed by the bunching system and two accelerating structures all embedded in solenoidal magnetic field and a magnetic chicane. Three sub-harmonic bunchers (SHB), a prebuncher and a travelling wave buncher constitute the bunching system. The phase coding process done by the sub-harmonic bunching system produces unwanted satellite bunches between the successive main bunches. The beam dynamics of the CTF3 Drive Beam injector is reoptimised with the goal of improving the injector performance and in particular decreasing the satellite population, the beam loss in the magnetic chicane and the beam emittance in transverse plane compare to the original model based on P. Ur...

  12. Support Vector Machine Classification of Drunk Driving Behaviour.

    Science.gov (United States)

    Chen, Huiqin; Chen, Lei

    2017-01-23

    Alcohol is the root cause of numerous traffic accidents due to its pharmacological action on the human central nervous system. This study conducted a detection process to distinguish drunk driving from normal driving under simulated driving conditions. The classification was performed by a support vector machine (SVM) classifier trained to distinguish between these two classes by integrating both driving performance and physiological measurements. In addition, principal component analysis was conducted to rank the weights of the features. The standard deviation of R-R intervals (SDNN), the root mean square value of the difference of the adjacent R-R interval series (RMSSD), low frequency (LF), high frequency (HF), the ratio of the low and high frequencies (LF/HF), and average blink duration were the highest weighted features in the study. The results show that SVM classification can successfully distinguish drunk driving from normal driving with an accuracy of 70%. The driving performance data and the physiological measurements reported by this paper combined with air-alcohol concentration could be integrated using the support vector regression classification method to establish a better early warning model, thereby improving vehicle safety.

  13. Support Vector Machine Classification of Drunk Driving Behaviour

    Directory of Open Access Journals (Sweden)

    Huiqin Chen

    2017-01-01

    Full Text Available Alcohol is the root cause of numerous traffic accidents due to its pharmacological action on the human central nervous system. This study conducted a detection process to distinguish drunk driving from normal driving under simulated driving conditions. The classification was performed by a support vector machine (SVM classifier trained to distinguish between these two classes by integrating both driving performance and physiological measurements. In addition, principal component analysis was conducted to rank the weights of the features. The standard deviation of R–R intervals (SDNN, the root mean square value of the difference of the adjacent R–R interval series (RMSSD, low frequency (LF, high frequency (HF, the ratio of the low and high frequencies (LF/HF, and average blink duration were the highest weighted features in the study. The results show that SVM classification can successfully distinguish drunk driving from normal driving with an accuracy of 70%. The driving performance data and the physiological measurements reported by this paper combined with air-alcohol concentration could be integrated using the support vector regression classification method to establish a better early warning model, thereby improving vehicle safety.

  14. 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.

  15. Automated driving safer and more efficient future driving

    CERN Document Server

    Horn, Martin

    2017-01-01

    The main topics of this book include advanced control, cognitive data processing, high performance computing, functional safety, and comprehensive validation. These topics are seen as technological bricks to drive forward automated driving. The current state of the art of automated vehicle research, development and innovation is given. The book also addresses industry-driven roadmaps for major new technology advances as well as collaborative European initiatives supporting the evolvement of automated driving. Various examples highlight the state of development of automated driving as well as the way forward. The book will be of interest to academics and researchers within engineering, graduate students, automotive engineers at OEMs and suppliers, ICT and software engineers, managers, and other decision-makers.

  16. Superconducting cavity driving with FPGA controller

    Energy Technology Data Exchange (ETDEWEB)

    Czarski, T.; Koprek, W.; Pozniak, K.T.; Romaniuk, R.S. [Warsaw Univ. of Technology (Poland); Simrock, S.; Brand, A. [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany); Chase, B.; Carcagno, R.; Cancelo, G. [Fermi National Accelerator Lab., Batavia, IL (United States); Koeth, T.W. [Rutgers - the State Univ. of New Jersey, NJ (United States)

    2006-07-01

    The digital control of several superconducting cavities for a linear accelerator is presented. The laboratory setup of the CHECHIA cavity and ACC1 module of the VU-FEL TTF in DESY-Hamburg have both been driven by a Field Programmable Gate Array (FPGA) based system. Additionally, a single 9-cell TESLA Superconducting cavity of the FNPL Photo Injector at FERMILAB has been remotely controlled from WUT-ISE laboratory with the support of the DESY team using the same FPGA control system. These experiments focused attention on the general recognition of the cavity features and projected control methods. An electrical model of the resonator was taken as a starting point. Calibration of the signal path is considered key in preparation for the efficient driving of a cavity. Identification of the resonator parameters has been proven to be a successful approach in achieving required performance; i.e. driving on resonance during filling and field stabilization during flattop time while requiring reasonable levels of power consumption. Feed-forward and feedback modes were successfully applied in operating the cavities. Representative results of the experiments are presented for different levels of the cavity field gradient. (orig.)

  17. Superconducting cavity driving with FPGA controller

    International Nuclear Information System (INIS)

    Czarski, T.; Koprek, W.; Pozniak, K.T.; Romaniuk, R.S.; Simrock, S.; Brand, A.; Chase, B.; Carcagno, R.; Cancelo, G.; Koeth, T.W.

    2006-01-01

    The digital control of several superconducting cavities for a linear accelerator is presented. The laboratory setup of the CHECHIA cavity and ACC1 module of the VU-FEL TTF in DESY-Hamburg have both been driven by a Field Programmable Gate Array (FPGA) based system. Additionally, a single 9-cell TESLA Superconducting cavity of the FNPL Photo Injector at FERMILAB has been remotely controlled from WUT-ISE laboratory with the support of the DESY team using the same FPGA control system. These experiments focused attention on the general recognition of the cavity features and projected control methods. An electrical model of the resonator was taken as a starting point. Calibration of the signal path is considered key in preparation for the efficient driving of a cavity. Identification of the resonator parameters has been proven to be a successful approach in achieving required performance; i.e. driving on resonance during filling and field stabilization during flattop time while requiring reasonable levels of power consumption. Feed-forward and feedback modes were successfully applied in operating the cavities. Representative results of the experiments are presented for different levels of the cavity field gradient. (orig.)

  18. Creating a driving profile for older adults using GPS devices and naturalistic driving methodology.

    Science.gov (United States)

    Babulal, Ganesh M; Traub, Cindy M; Webb, Mollie; Stout, Sarah H; Addison, Aaron; Carr, David B; Ott, Brian R; Morris, John C; Roe, Catherine M

    2016-01-01

    Background/Objectives : Road tests and driving simulators are most commonly used in research studies and clinical evaluations of older drivers. Our objective was to describe the process and associated challenges in adapting an existing, commercial, off-the-shelf (COTS), in-vehicle device for naturalistic, longitudinal research to better understand daily driving behavior in older drivers. Design : The Azuga G2 Tracking Device TM was installed in each participant's vehicle, and we collected data over 5 months (speed, latitude/longitude) every 30-seconds when the vehicle was driven.  Setting : The Knight Alzheimer's Disease Research Center at Washington University School of Medicine. Participants : Five individuals enrolled in a larger, longitudinal study assessing preclinical Alzheimer disease and driving performance.  Participants were aged 65+ years and had normal cognition. Measurements :  Spatial components included Primary Location(s), Driving Areas, Mean Centers and Unique Destinations.  Temporal components included number of trips taken during different times of the day.  Behavioral components included number of hard braking, speeding and sudden acceleration events. Methods :  Individual 30-second observations, each comprising one breadcrumb, and trip-level data were collected and analyzed in R and ArcGIS.  Results : Primary locations were confirmed to be 100% accurate when compared to known addresses.  Based on the locations of the breadcrumbs, we were able to successfully identify frequently visited locations and general travel patterns.  Based on the reported time from the breadcrumbs, we could assess number of trips driven in daylight vs. night.  Data on additional events while driving allowed us to compute the number of adverse driving alerts over the course of the 5-month period. Conclusions : Compared to cameras and highly instrumented vehicle in other naturalistic studies, the compact COTS device was quickly installed and transmitted high

  19. THE IMPACT OF TEXT DRIVING ON DRIVING SAFETY

    OpenAIRE

    Sanaz Motamedi; Jyh-Hone Wang

    2016-01-01

    In an increasingly mobile era, the wide availability of technology for texting and the prevalence of hands-free form have introduced a new safety concern for drivers. To assess this concern, a questionnaire was first deployed online to gain an understanding of drivers’ text driving experiences as well as their demographic information. The results from 232 people revealed that the majority of drivers are aware of the associated risks with texting while driving. However, more than one-fourth of...

  20. Semiclassical instability of warp drives

    Energy Technology Data Exchange (ETDEWEB)

    Barcelo, C [Instituto de Astrofisica de Andalucia, IAA-CSIC, Glorieta de la Astronomia s/n, 18008 Granada (Spain); Finazzi, S; Liberati, S, E-mail: carlos@iaa.e, E-mail: finazzi@sissa.i, E-mail: liberati@sissa.i

    2010-05-01

    Warp drives, at least theoretically, provide a way to travel at superluminal speeds. However, even if one succeeded in providing the necessary exotic matter to construct them, it would still be necessary to check whether they would survive to the switching on of quantum effects. In this contribution we will report on the behaviour of the Renormalized Stress-Energy Tensor (RSET) in the spacetimes associated with superluminal warp drives. We find that the RSET will exponentially grow in time close to the front wall of the superluminal bubble, hence strongly supporting the conclusion that the warp-drive geometries are unstable against semiclassical back-reaction.

  1. Drive Electric Vermont Case Study

    Energy Technology Data Exchange (ETDEWEB)

    Wagner, Fred [Energetics Incorporated, Columbia, MD (United States); Roberts, Dave [Vermont Energy Investment Corporation (VEIC), Burlington, VT (United States); Francfort, Jim [Idaho National Lab. (INL), Idaho Falls, ID (United States); White, Sera [Idaho National Lab. (INL), Idaho Falls, ID (United States)

    2016-03-01

    Currently in the United States, the heavy majority of plug-in electric vehicle (PEV) sales have been in highly conducive, selected, metropolitan areas; opposed to more broad distribution across the country. The U.S. Department of Energy’s EV Everywhere Grand Challenge is looking carefully at the barriers and opportunities that exist to enable small and midsize communities to partake in the PEV market and benefit from the economic and environmental advantages of PEVs. In order to gain insight into these challenges and barriers, DOE selected a success story (i.e., Drive Electric Vermont) as the subject of this case study, as the state of Vermont is tied with Detroit, Michigan in having the highest percentage of 2014 (most recent complete data) PEV registrations for cold weather U.S. cities and has seen more than a sixfold increase in charging stations over the last three years. The overall objective of this case study was to use the lessons learned from Drive Electric Vermont to determine what activities are most effective at encouraging acquisitions of PEVs and deployment of charging infrastructure in small to midsize communities, prioritizing and sequencing their implementation, identifying robust means for extrapolation, and applying this understanding to other small to midsize communities across the nation. The Drive Electric Vermont Program was formed in 2012 with a goal of increasing the use of electrified transportation in Vermont through policy development, education and outreach, and infrastructure development. The Drive Electric Vermont Program can be broadly broken into four components: (1) strategic planning/leadership, (2) stakeholder/partnership development, (3) education and outreach, and (4) incentives. The early phases of the program focused heavily on strategic planning, and stakeholder and partnership development, followed by a transition to education and outreach activities, charging infrastructure development, and grant and incentive programs

  2. Driving Safety and Fitness to Drive in Sleep Disorders.

    Science.gov (United States)

    Tippin, Jon; Dyken, Mark Eric

    2017-08-01

    Driving an automobile while sleepy increases the risk of crash-related injury and death. Neurologists see patients with sleepiness due to obstructive sleep apnea, narcolepsy, and a wide variety of neurologic disorders. When addressing fitness to drive, the physician must weigh patient and societal health risks and regional legal mandates. The Driver Fitness Medical Guidelines published by the National Highway Traffic Safety Administration (NHTSA) and the American Association of Motor Vehicle Administrators (AAMVA) provide assistance to clinicians. Drivers with obstructive sleep apnea may continue to drive if they have no excessive daytime sleepiness and their apnea-hypopnea index is less than 20 per hour. Those with excessive daytime sleepiness or an apnea-hypopnea index of 20 per hour or more may not drive until their condition is effectively treated. Drivers with sleep disorders amenable to pharmaceutical treatment (eg, narcolepsy) may resume driving as long as the therapy has eliminated excessive daytime sleepiness. Following these guidelines, documenting compliance to recommended therapy, and using the Epworth Sleepiness Scale to assess subjective sleepiness can be helpful in determining patients' fitness to drive.

  3. Preventing distracted driving among college students: Addressing smartphone use.

    Science.gov (United States)

    Hassani, Sahar; Kelly, Erin H; Smith, Jennifer; Thorpe, Sara; Sozzer, Fatima H; Atchley, Paul; Sullivan, Elroy; Larson, Dean; Vogel, Lawrence C

    2017-02-01

    Based on the National Highway Traffic Safety Association's (NHTSA) Report, fatalities due to distracted driving are on the rise and the highest proportion of fatalities by age group is the 20-29 year old category. To date little has been done to educate college students about the dangers of distracted driving and engage these students in promoting a safe driving culture. Intervening among college students has the potential for making real-time behavior change, can foster a lifetime of safe driving habits among these students, and can help contribute to a culture of safe driving that can be created and sustained through positive messages from peers. The goals of this study were to develop, implement and evaluate a distracted driving presentation for college students to change knowledge, attitude and behavior on distracted driving. A 30-min, multi-media presentation on distracted driving was presented to 19 colleges and universities, totaling 444 college students (mean age 23.7±7.0 years of age, 61% females, 39% males). Students completed three surveys: prior to the workshop (interview 1), immediately after the workshop (interview 2), and 3 months following the workshop (interview 3). We assessed changes between interview 1 and interview 2 and found 15 of the 15 attitude-knowledge based questions significantly improved after the course. In addition, we assessed changes from interviews 1 and 3, and found 11 of the 15 attitude-knowledge based questions maintained their significance. Responses to behavior related questions at three months were also compared to baseline, and significant improvements were found for 12 of the 14 questions. While this study was successful in improving the short-term attitude-knowledge and behaviors on distracted driving, work is needed to sustain (and evaluate) long-term effects. Copyright © 2016 Elsevier Ltd. All rights reserved.

  4. 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.

  5. Multidisciplinary design of electrical drives

    Energy Technology Data Exchange (ETDEWEB)

    Blaabjerg, F.; Rasmussen, P.O.; Pedersen, J.K.

    1999-07-01

    Traditionally, simulation tools for drives can simulate electrical parameters, torque and different loads. Those parameters are in many cases appropriate. However, power electronics in drives will also influence on torque ripple, temperature, vibration and acoustical noise from the motor and it is necessary to include those phenomena in the next generation of simulation tools for electrical drives. This paper describes a new design program where acoustic noise of electromagnetic origin can be simulated and even be heard by the motor and drives designer. The design program is based on a simple vibrational/acoustic model where the parameters can be calculated based on the geometry of the motor. Examples of vibrational/acoustical modelling are included and verified in both time and frequency domain. Special emphasis is on the switched reluctance motor. (au)

  6. Clinical Action against Drunk Driving.

    Directory of Open Access Journals (Sweden)

    Donald A Redelmeier

    2017-02-01

    Full Text Available In advance of a safety campaign on 17 March 2017, Donald Redelmeier and Allan Detsky call on physicians and clinical colleagues to reduce the chances that patients will drive drunk.

  7. Driving safety in Parkinson's disease.

    Science.gov (United States)

    Zesiewicz, T A; Cimino, C R; Malek, A R; Gardner, N; Leaverton, P L; Dunne, P B; Hauser, R A

    2002-12-10

    In this study, 39 patients with PD and 25 control subjects without neurologic disease completed testing in a driving simulator. PD patients had more total collisions on the driving simulator than control subjects (t = -3.7, p < 0.01). In PD patients, collisions were associated with Hoehn and Yahr stage (chi(2) = 12.4, p = 0.006) and correlated with Unified Parkinson's Disease Rating Scale score (r = 0.5, p < 0.01).

  8. Warp drive with zero expansion

    Energy Technology Data Exchange (ETDEWEB)

    Natario, Jose [Department of Mathematics, Instituto Superior Tecnico (Portugal)

    2002-03-21

    It is commonly believed that Alcubierre's warp drive works by contracting space in front of the warp bubble and expanding the space behind it. We show that this contraction/expansion is but a marginal consequence of the choice made by Alcubierre and explicitly construct a similar spacetime where no contraction/expansion occurs. Global and optical properties of warp-drive spacetimes are also discussed.

  9. Selective Perception for Robot Driving

    Science.gov (United States)

    1992-05-01

    models are theories of human cognitive activity during driving. Van der Molen and Botticher recently reviewed several of these models [ van der Molen 871...how to represent driving knowledge, how to perceive traffic situations, or how to process information to obtain actions. Van der Molen and Botticher...attempted to compare the operations of various models objectively on the same task [Rothengatter 88, van der Molen 87], but the models could be

  10. Low backlash direct drive actuator

    Science.gov (United States)

    Kuklo, Thomas C.

    1994-01-01

    A low backlash direct drive actuator is described which comprises a motor such as a stepper motor having at least 200 steps per revolution; a two part hub assembly comprising a drive hub coaxially attached to the shaft of the motor and having a plurality of drive pins; a driven hub having a plurality of bores in one end thereof in alignment with the drive pins in the drive hub and a threaded shaft coaxially mounted in an opposite end of the driven hub; and a housing having a central bore therein into which are fitted the drive hub and driven hub, the housing having a motor mount on one end thereof to which is mounted the stepper motor, and a closed end portion with a threaded opening therein coaxial with the central bore in the housing and receiving therein the threaded shaft attached to the driven hub. Limit switches mounted to the housing cooperate with an enlarged lip on the driven hub to limit the lateral travel of the driven hub in the housing, which also acts to limit the lateral travel of the threaded shaft which functions as a lead screw.

  11. Sleep apnoea and driving risk: the need for regulation

    Directory of Open Access Journals (Sweden)

    Walter T. McNicholas

    2015-12-01

    Full Text Available Obstructive sleep apnoea syndrome (OSAS is a highly prevalent chronic respiratory disorder with prevalence among adult males of ≥10%. The most common daytime symptom associated with OSAS is excessive sleepiness, which in more severe manifestations can result in sleepiness at the wheel while driving and probably contributes to the substantial increase in accident risk among patients with OSAS. Fortunately, current evidence indicates that successful therapy of OSAS, particularly with continuous positive airway pressure, can bring the accident risk down to levels similar to an equivalent general population. The recognition of the increased driving accident risk in OSAS prompted the Transport and Mobility Directorate of the European Commission to establish a working group on this topic in 2012, which ultimately led to a revision of Annex III of the EU Driving Licence Directive, which is subject to mandatory implementation by European Union member states by December 2015. This directive specifies that patients with moderate or severe OSAS associated with significant daytime sleepiness should be prohibited from driving until effective therapy is established. These new regulations are designed to balance the legitimate objective of public safety with not penalising OSAS patients who are complying with effective therapy. Successful implementation of regulations on driving in OSAS patients must also include measures to educate relevant stakeholders including patients, medical personnel, traffic police and employers in the transport industry. The key objective is to encourage patients with possible OSAS to seek diagnosis and treatment and not to inhibit OSAS patients from coming forward.

  12. Sleep apnoea and driving risk: the need for regulation.

    Science.gov (United States)

    McNicholas, Walter T; Rodenstein, Daniel

    2015-12-01

    Obstructive sleep apnoea syndrome (OSAS) is a highly prevalent chronic respiratory disorder with prevalence among adult males of ≥10%. The most common daytime symptom associated with OSAS is excessive sleepiness, which in more severe manifestations can result in sleepiness at the wheel while driving and probably contributes to the substantial increase in accident risk among patients with OSAS. Fortunately, current evidence indicates that successful therapy of OSAS, particularly with continuous positive airway pressure, can bring the accident risk down to levels similar to an equivalent general population. The recognition of the increased driving accident risk in OSAS prompted the Transport and Mobility Directorate of the European Commission to establish a working group on this topic in 2012, which ultimately led to a revision of Annex III of the EU Driving Licence Directive, which is subject to mandatory implementation by European Union member states by December 2015. This directive specifies that patients with moderate or severe OSAS associated with significant daytime sleepiness should be prohibited from driving until effective therapy is established. These new regulations are designed to balance the legitimate objective of public safety with not penalising OSAS patients who are complying with effective therapy. Successful implementation of regulations on driving in OSAS patients must also include measures to educate relevant stakeholders including patients, medical personnel, traffic police and employers in the transport industry. The key objective is to encourage patients with possible OSAS to seek diagnosis and treatment and not to inhibit OSAS patients from coming forward. Copyright ©ERS 2015.

  13. High-power converters and AC drives

    CERN Document Server

    Wu, Bin

    2017-01-01

    This new edition reflects the recent technological advancements in the MV drive industry, such as advanced multilevel converters and drive configurations. It includes three new chapters, Control of Synchronous Motor Drives, Transformerless MV Drives, and Matrix Converter Fed Drives. In addition, there are extensively revised chapters on Multilevel Voltage Source Inverters and Voltage Source Inverter-Fed Drives. This book includes a systematic analysis on a variety of high-power multilevel converters, illustrates important concepts with simulations and experiments, introduces various megawatt drives produced by world leading drive manufacturers, and addresses practical problems and their mitigations methods.

  14. Efficient Driving of Piezoelectric Transducers Using a Biaxial Driving Technique.

    Directory of Open Access Journals (Sweden)

    Samuel Pichardo

    Full Text Available Efficient driving of piezoelectric materials is desirable when operating transducers for biomedical applications such as high intensity focused ultrasound (HIFU or ultrasound imaging. More efficient operation reduces the electric power required to produce the desired bioeffect or contrast. Our preliminary work [Cole et al. Journal of Physics: Condensed Matter. 2014;26(13:135901.] suggested that driving transducers by applying orthogonal electric fields can significantly reduce the coercivity that opposes ferroelectric switching. We present here the experimental validation of this biaxial driving technique using piezoelectric ceramics typically used in HIFU. A set of narrow-band transducers was fabricated with two sets of electrodes placed in an orthogonal configuration (following the propagation and the lateral mode. The geometry of the ceramic was chosen to have a resonance frequency similar for the propagation and the lateral mode. The average (± s.d. resonance frequency of the samples was 465.1 (± 1.5 kHz. Experiments were conducted in which each pair of electrodes was driven independently and measurements of effective acoustic power were obtained using the radiation force method. The efficiency (acoustic/electric power of the biaxial driving method was compared to the results obtained when driving the ceramic using electrodes placed only in the pole direction. Our results indicate that the biaxial method increases efficiency from 50% to 125% relative to the using a single electric field.

  15. i3Drive, a 3D interactive driving simulator.

    Science.gov (United States)

    Ambroz, Miha; Prebil, Ivan

    2010-01-01

    i3Drive, a wheeled-vehicle simulator, can accurately simulate vehicles of various configurations with up to eight wheels in real time on a desktop PC. It presents the vehicle dynamics as an interactive animation in a virtual 3D environment. The application is fully GUI-controlled, giving users an easy overview of the simulation parameters and letting them adjust those parameters interactively. It models all relevant vehicle systems, including the mechanical models of the suspension, power train, and braking and steering systems. The simulation results generally correspond well with actual measurements, making the system useful for studying vehicle performance in various driving scenarios. i3Drive is thus a worthy complement to other, more complex tools for vehicle-dynamics simulation and analysis.

  16. Educational Attainment: Success to the Successful

    Science.gov (United States)

    Anthony, Peter; Gould, David; Smith, Gina

    2013-01-01

    Systems archetypes are patterns of structure found in systems that are helpful in understanding some of the dynamics within them. The intent of this study was to examine educational attainment data using the success-to-the-successful archetype as a model to see if it helps to explain the inequality observed in the data. Data covering 1990 to 2009…

  17. College Success Courses: Success for All

    Science.gov (United States)

    Coleman, Sandra Lee; Skidmore, Susan Troncoso; Weller, Carol Thornton

    2018-01-01

    College success courses (CSCs), or orientation courses, are offered by community colleges and universities to facilitate the success of first-time-in-college students. Primarily, these courses are designed to address students' nonacademic deficiencies, such as weak study habits and poor organizational skills, and to familiarize students with…

  18. Driving performance at lateral system limits during partially automated driving.

    Science.gov (United States)

    Naujoks, Frederik; Purucker, Christian; Wiedemann, Katharina; Neukum, Alexandra; Wolter, Stefan; Steiger, Reid

    2017-11-01

    This study investigated driver performance during system limits of partially automated driving. Using a motion-based driving simulator, drivers encountered different situations in which a partially automated vehicle could no longer safely keep the lateral guidance. Drivers were distracted by a non-driving related task on a touch display or driving without an additional secondary task. While driving in partially automated mode drivers could either take their hands off the steering wheel for only a short period of time (10s, so-called 'Hands-on' variant) or for an extended period of time (120s, so-called 'Hands-off' variant). When the system limit was reached (e.g., when entering a work zone with temporary lines), the lateral vehicle control by the automation was suddenly discontinued and a take-over request was issued to the drivers. Regardless of the hands-off interval and the availability of a secondary task, all drivers managed the transition to manual driving safely. No lane exceedances were observed and the situations were rated as 'harmless' by the drivers. The lack of difference between the hands-off intervals can be partly attributed to the fact that most of the drivers kept contact to the steering wheel, even in the hands-off condition. Although all drivers were able to control the system limits, most of them could not explain why exactly the take-over request was issued. The average helpfulness of the take-over request was rated on an intermediate level. Consequently, providing drivers with information about the reason for a system limit can be recommended. Copyright © 2017 Elsevier Ltd. All rights reserved.

  19. Exploring Forensic Implications of the Fusion Drive

    Directory of Open Access Journals (Sweden)

    Shruti Gupta

    2014-09-01

    Full Text Available This paper explores the forensic implications of Apple's Fusion Drive. The Fusion Drive is an example of auto-tiered storage. It uses a combination of a flash drive and a magnetic drive. Data is moved between the drives automatically to maximize system performance. This is different from traditional caches because data is moved and not simply copied. The research included understanding the drive structure, populating the drive, and then accessing data in a controlled setting to observe data migration strategies. It was observed that all the data is first written to the flash drive with 4 GB of free space always maintained. If data on the magnetic drive is frequently accessed, it is promoted to the flash drive while demoting other information. Data is moved at a block-level and not a file-level. The Fusion Drive didn't alter the timestamps of files with data migration.

  20. Success stories in nuclear science

    International Nuclear Information System (INIS)

    Fox, M.R.

    1990-01-01

    The low level of public understanding of energy in general, and nuclear energy in particular in the United States is well known, especially by the world's scientific community. A technologically leading nation such as the United States, will not remain so for long, if fear, anxiety, worry, anger, and technological misinformation continue to influence if not drive science and energy policy. Our society, our freedom, and even our national security are at risk when sound science and energy policies are inhibited or prevented. As a scientific organization, the American Nuclear Society believes that it is our responsibility, not merely an obligation, to get involved with the educational processes of our nation. Through the Public Information Committee of ANS a variety of educational activities have been undertaken, with remarkable success. This presentation describes some of these and some of the many lessons learned from these activities and about ourselves

  1. Attitudes of Success.

    Science.gov (United States)

    Pendarvis, Faye

    This document investigates the attitudes of successful individuals, citing the achievement of established goals as the criteria for success. After offering various definitions of success, the paper focuses on the importance of self-esteem to success and considers ways by which the self-esteem of students can be improved. Theories of human behavior…

  2. Driving safety in elderly individuals.

    Science.gov (United States)

    Marottoli, R A

    1993-05-01

    Driving safety in elderly individuals is becoming an increasingly important issue in geriatrics and in medical practice. The number of elderly drivers is increasing as the population ages, and especially as current generations of female drivers age. Concern is raised about their safe operation of motor vehicles because of the increasing likelihood with advancing age of developing conditions that may adversely affect the visual, cognitive, and motor abilities integral to driving. But this issue is not only a medical one, since there are social and political components as well. This discussion will describe the background of this issue, focus on the changes that may occur with aging and their potential relationship to driving ability, and, finally, will outline an approach that physicians may employ in their practice.

  3. Drive: Theory and Construct Validation.

    Science.gov (United States)

    Siegling, Alex B; Petrides, K V

    2016-01-01

    This article explicates the theory of drive and describes the development and validation of two measures. A representative set of drive facets was derived from an extensive corpus of human attributes (Study 1). Operationalised using an International Personality Item Pool version (the Drive:IPIP), a three-factor model was extracted from the facets in two samples and confirmed on a third sample (Study 2). The multi-item IPIP measure showed congruence with a short form, based on single-item ratings of the facets, and both demonstrated cross-informant reliability. Evidence also supported the measures' convergent, discriminant, concurrent, and incremental validity (Study 3). Based on very promising findings, the authors hope to initiate a stream of research in what is argued to be a rather neglected niche of individual differences and non-cognitive assessment.

  4. CLIC Drive Beam Position Monitor

    CERN Document Server

    Smith, S; Gudkov, D; Soby, L; Syratchev, I

    2011-01-01

    CLIC, an electron-positron linear collider proposed to probe the TeV energy scale, is based on a two-beam scheme where RF power to accelerate a high energy luminosity beam is extracted from a high current drive beam. The drive beam is efficiently generated in a long train at modest frequency and current then compressed in length and multiplied in frequency via bunch interleaving. The drive beam decelerator requires >40000 quadrupoles, each holding a beam position monitor (BPM). Though resolution requirements are modest (2 microns) these BPMs face several challenges. They must be compact and inexpensive. They must operate below waveguide cutoff to insure locality of position signals, ruling out processing at the natural 12 GHz bunch spacing frequency. Wakefields must be kept low. We find compact conventional stripline BPM with signals processed below 40 MHz can meet requirements. Choices of mechanical design, operating frequency, bandwidth, calibration and processing algorithm are presented. Calculations of wa...

  5. Glare disability and driving safety.

    Science.gov (United States)

    Babizhayev, M A

    2003-01-01

    Increasing investigation of the visual elements of safe driving environments may be of great benefit to society. Visual disability appears to be only one of many visual factors related to traffic accidents. The purpose of this article was to examine the type of visual impairment mediated by the increased glare sensitivity in adult drivers using the original halometer glare test. In this article, the visual sensory, cognitive and motor functions relevant to driving, their measurement, the epidemiology and prevention of age-associated functional impairments and the relationship of functional impairments to both self-reported driving and the imposition of legal restrictions are reviewed. The problem of night and tunnel driving is the most urgent in relation to the effects of glare from vehicle headlights on motion perception of drivers. The reduced mesopic vision and increased sensitivity to glare are accompanied by an increased risk of nighttime accidents. Elderly drivers and patients with beginning cataract cannot sufficiently fulfill the criteria for night driving ability because of contrast and glare sensitivity. It is indispensable for the parameters mentioned to be carefully measured and for drivers to be informed that night driving ability may be impaired, even if visual acuity is sufficient. It would be advisable for traffic safety if simple tests for contrast and glare sensitivity were implemented for vehicles and/or were regularly added to the requirements for a driver's licence, at least for older drivers. The age, functional status and test result limits should be defined to avoid a risk factor in traffic. Copyright 2003 S. Karger AG, Basel

  6. Ontogenetic scaling of caudal fin shape in Squalus acanthias (Chondrichthyes, Elasmobranchii): a geometric morphometric analysis with implications for caudal fin functional morphology.

    Science.gov (United States)

    Reiss, Katie L; Bonnan, Matthew F

    2010-07-01

    The shark heterocercal caudal fin and its contribution to locomotion are of interest to biologists and paleontologists. Current hydrodynamic data show that the stiff dorsal lobe leads the ventral lobe, both lobes of the tail are synchronized during propulsion, and tail shape reflects its overall locomotor function. Given the difficulties surrounding the analysis of shark caudal fins in vivo, little is known about changes in tail shape related to ontogeny and sex in sharks. A quantifiable analysis of caudal fin shape may provide an acceptable proxy for inferring gross functional morphology where direct testing is difficult or impossible. We examined ontogenetic and sex-related shape changes in the caudal fins of 115 Squalus acanthias museum specimens, to test the hypothesis that significant shape changes in the caudal fin shape occur with increasing size and between the sexes. Using linear and geometric morphometrics, we examined caudal shape changes within the context of current hydrodynamic models. We found no statistically significant linear or shape difference between sexes, and near-isometric scaling trends for caudal dimensions. These results suggest that lift and thrust increase linearly with size and caudal span. Thin-plate splines results showed a significant allometric shape change associated with size and caudal span: the dorsal lobe elongates and narrows, whereas the ventral lobe broadens and expands ventrally. Our data suggest a combination of caudal fin morphology with other body morphology aspects, would refine, and better elucidate the hydrodynamic factors (if any) that underlie the significant shape changes we report here for S. acanthias.

  7. Spatial, seasonal and ontogenetic variation in the diet of Astyanax aff. fasciatus (Ostariophysi: Characidae in an Atlantic Forest river, Southern Brazil

    Directory of Open Access Journals (Sweden)

    Luciano Lazzarini Wolff

    Full Text Available This study described the feeding habits of the characin Astyanax aff. fasciatus. The diet compositions of specimens from two sites (A and B on a river in Southern Brazil were compared according to the size of individuals and seasonal period. The collections were performed monthly from March 2005 to February 2006, where the stomach contents of 290 specimens were assessed. Food items for A. aff. fasciatus were basically composed of plants and insects, especially leaf fragments, seeds, fruits, filamentous algae, aquatic and terrestrial insects and insect fragments. At site A, the most common items were insect and plant fragments. Conversely at site B, plant fragments were more representative. In general, all items of animal origin showed the highest feeding index values at site A, whereas at site B detritus and grass items were more abundant. The composition of items varied seasonally, with higher diversity of items being recorded during the spring at both sites. Smaller individuals preferred items of animal origin, while the larger ones consumed mainly items of plant origin. According to its size, A. aff. fasciatus in this study may be considered a species with insectivorous tendencies when immature or herbivorous tendencies when adult. Nevertheless, its feeding habits may be flexible according to resource availability, showing wide ontogenetic, besides spatial and temporal variation.

  8. Influence of roadside infrastructure on driving behavior: driving simulator study

    NARCIS (Netherlands)

    Horst, A.R.A. van der; Ridder, S. de

    2007-01-01

    This paper describes the results of a driving simulator study that focused on the influence of roadside infrastructure on speed choice and lateral placement of car drivers. A review of the RISER detailed accident database revealed that lateral positioning and speed of the vehicle were two of the

  9. Driving and Age-Related Macular Degeneration

    OpenAIRE

    Owsley, Cynthia; McGwin, Gerald

    2008-01-01

    This article reviews the research literature on driving and age-related macular degeneration, which is motivated by the link between driving and the quality of life of older adults and their increased collision rate. It addresses the risk of crashes, driving performance, driving difficulty, self-regulation, and interventions to enhance, safety, and considers directions for future research.

  10. Digital control of electric drives

    CERN Document Server

    Koziol, R; Szklarski, L

    1992-01-01

    The electromechanical systems employed in different branches of industry are utilized most often as drives of working machines which must be fed with electric energy in a continuous, periodic or even discrete way. Some of these machines operate at constant speed, others require wide and varying energy control. In many designs the synchronous cooperation of several electric drives is required in addition to the desired dynamic properties. For these reasons the control of the cooperation and dynamics of electromechanical systems requires the use of computers.This book adopts an unusual approach

  11. Control-rod driving mechanism

    International Nuclear Information System (INIS)

    Jodoi, Takashi.

    1976-01-01

    Purpose: To prevent falling of control rods due to malfunction. Constitution: The device of the present invention has a scram function in particular, and uses principally a fluid pressure as a scram accelerating means. The control rod is held by upper and lower holding devices, which are connected by a connecting mechanism. This connecting mechanism is designed to be detachable only at the lower limit of driving stroke of the control rod so that there occurs no erroneous scram resulting from careless disconnection of the connecting mechanism. Further, scramming operation due to own weight of the scram operating portion such as control rod driving shaft may be effected to increase freedom. (Kamimura, M.)

  12. 5 keys to business analytics program success

    CERN Document Server

    Boyer, John; Green, Brian; Harris, Tracy; Van De Vanter, Kay

    2012-01-01

    With business analytics is becoming increasingly strategic to all types of organizations and with many companies struggling to create a meaningful impact with this emerging technology, this work-based on the combined experience of 10 organizations that display excellence and expertise on the subject-shares the best practices, discusses the management aspects and sociology that drives success, and uncovers the five key aspects behind the success of some of the top business analytics programs in the industry. Readers will learn about numerous topics, including how to create and manage a changing

  13. A pneumatic cylinder driving polyhedron mobile mechanism

    Science.gov (United States)

    Ding, Wan; Kim, Sung-Chan; Yao, Yan-An

    2012-03-01

    A novel pneumatic cylinder driving polyhedron mobile mechanism is proposed in this paper. The mechanism is comprised of 5 tetrahedrons which includes a pneumatic cylinder in each edge. It locomotes by rolling and the rolling principle refers to the center of mass (CM) of the mechanism moved out of the supporting area and let it tip over through the controlling of the motion sequence of these cylinders. Firstly, the mathematical model is built to analysis the relation between the configuration and the CM of the mechanism. Then, a binary control strategy is developed to simplify and improve the control of this mobile mechanism. After that, dynamic simulation is performed to testify the analytical validity and feasibility of the rolling gaits. At last, a prototype is fabricated to achieve the rolling successfully to demonstrate the proposed concept.

  14. Adjustable speed drives improve circulating water system

    International Nuclear Information System (INIS)

    Dent, R.A.; Dicic, Z.

    1994-01-01

    This paper illustrates the integration of electrical and mechanical engineering requirements to produce a solution to past problems and future operating demands. The application of adjustable speed drives in the modifications of the circulating water system at Indian Point No. 3 Nuclear Power Plant provided increased operating flexibility, efficiency and avoided otherwise costly renovations to the plant electrical systems. Rectification of the original inadequate design of the circulating water system, in addition to maximizing plant efficiency consistent with environmental considerations, formed the basis for this modification. This entailed replacement of all six circulating water pumps and motors and physical modifications to the intake system. This paper details the methodology used in this engineering task. The new system was installed successfully and has been operating reliably and economically for the past eight years

  15. Comparison of drive systems for pulsed synchronous machines - an overview

    International Nuclear Information System (INIS)

    Baumgart, G.E.; Boenig, H.J.

    1986-01-01

    Magnetically confined plasma fusion experiments require large pulses of energy to be delivered into coil systems. One of the most effective methods of generating these high energy pulses is to convert stored inertial energy into electrical energy. Large synchronous generators of both the vertical and horizontal shaft type have been successfully used for this purpose. As the pulsed energy is delivered to the load, the inertial energy of the rotor of the machine is changed into electrical energy, causing the rotor to slow down. A drive system is required to accelerate the generator from standstill to the maximum operating speed and between load pulses from a reduced operating speed to the maximum speed. There are several types of drive systems that can be used for this application. An overview of six candidate drive systems is presented and comparisons of cost, performance, efficiency and line effects for these systems are described

  16. Comparison of drive systems for pulsed synchronous machines: an overview

    International Nuclear Information System (INIS)

    Baumgart, G.E.; Boenig, H.J.

    1985-01-01

    Magnetically confined plasma fusion experiments require large pulses of energy to be delivered into coil systems. One of the most effective methods of generating these high energy pulses is to convert stored inertial energy into electrical energy. Large synchronous generators of both the vertical and horizontal shaft type have been successfully used for this purpose. As the pulsed energy is delivered to the load, the inertial energy of the rotor of the machine is changed into electrical energy, causing the rotor to slow down. A drive system is required to accelerate the generator from standstill to the maximum operating speed and between load pulses from a reduced operating speed to the maximum speed. There are several types of drive systems that can be used for this application. An overview of six candidate drive systems is presented and comparisons of cost, performance, efficiency, and line effects for these systems are described

  17. Electrohydraulic drive system with planetary superposed gears

    Energy Technology Data Exchange (ETDEWEB)

    Graetz, A.; Klimek, K.H.; Welz, H.

    1989-01-01

    To prevent drive problems in ploughs the drives must be designed in such a way as to compensate for asymmetries. If electromechanical drives are replaced by an electrohydraulic drive system with superposed planetary gears and hydrostatic torque reaction supports the following advantages occur: load-free acceleration, load equalisation between main and auxiliary drive, overload protection, and reduction of systems vibrations. 2 figs., 2 tabs.

  18. FOREIGN DRIVING LICENCES IN SWITZERLAND

    CERN Document Server

    Relatiopns with the Host States Service

    2001-01-01

    1. PERSONS RESIDING IN SWITZERLAND 1.1 Holders of a B, C, D or E-type carte de légitimation For holders of B, C, D or E-type cartes de légitimation issued by the Swiss Federal Department for Foreign Affairs (Département fédéral suisse des Affaires étrangères, hereinafter called DFAE), current non-Swiss national driving licences are valid in Switzerland. Should they so wish, holders of such driving licences may apply to the relevant roads authority in the canton where they live (Service des Automobiles et de la Navigation ; for Geneva call 022/343 02 00, website: http://www.geneve.ch/san/welcome.html, for Vaud call 021/316 82 10, website: http://www.dse.vd.ch/auto/index.html) in order to exchange their driving licence for an equivalent Swiss licence. However, exchanges are not permitted if the driving licence was issued in a foreign country during a stay there of less than six months' duration while the person concerned was officially...

  19. Drive-By-Wire Technology

    Science.gov (United States)

    2001-05-29

    Symposium Intelligent Systems for the Objective Fleet uTransmission controls uSteering (both on-transmission and under-carriage) uBraking (service and...parking) uTransmission select uThrottle uOther Electromechanical Opportunities uTurret drives (elevation, traverse) uAutomatic propellant handling systems

  20. Foreign driving licences in Switzerland

    CERN Multimedia

    DG Unit

    2009-01-01

    1. Persons residing in Switzerland 1.1 Holders of a B, C, D, E or P-type "carte de légitimation" For holders of a B, C, D, E or P-type "carte de légitimation" issued by the Swiss Federal Department for Foreign Affairs (DFAE), current non-Swiss national driving licences are valid in Switzerland. If they so wish, holders of such driving licences may apply to the relevant road licensing authority in the canton where they live (Service des Automobiles et de la Navigation; for Geneva call + 41 22 388 30 30, website http://www.geneve.ch/san; for Vaud call + 41 21 316 82 10, website http://www.san.vd.ch/index.html) to exchange their driving licence for an equivalent Swiss licence (they must pass a test if they are not citizens of countries with which Switzerland has concluded an agreement on this matter, e.g. Member States of the European Union, the United States and Japan). However, such an exchange is not possible if the driving licence was issued in a foreign country during a...

  1. Safe Driving After Propofol Sedation.

    Science.gov (United States)

    Summerlin-Grady, Lee; Austin, Paul N; Gabaldon, Dion A

    2017-10-01

    Propofol is a short-acting medication with fast cognitive and psychomotor recovery. However, patients are usually instructed not to drive a motor vehicle for 24 hours after receiving propofol. The purpose of this article was to review the evidence examining when it is safe to drive after receiving propofol for sedation for diagnostic and surgical procedures. This is a systematic review of the literature. A search of the literature was conducted using Google Scholar, PubMed, and the Cochrane Library for the time period 1990 to 2015. Two randomized controlled trials and two observational studies met the inclusion criteria. Using a simulator, investigators examined driving ability of subjects who received modest doses (about 100 mg) of propofol for endoscopic procedures and surveyed subjects who drove immediately after discharge. There were methodological concerns with the studies such as small sample sizes, modest doses of propofol, and three of the four studies were done in Japan by the same group of investigators limiting generalizability. This limited research suggests that it may be safe for patients to drive sooner than 24 hours after receiving propofol. However, large multicenter trials using heterogenous samples using a range of propofol doses are needed to support an evidence-based revision to the current discharge guidelines for patients receiving propofol. Copyright © 2016 American Society of PeriAnesthesia Nurses. Published by Elsevier Inc. All rights reserved.

  2. Driving When You Have Cataracts

    Science.gov (United States)

    ... asp Wear your safety belt Always wear your safety belt when you are driving or riding in a car. Make sure that every person who is riding with you also is buckled up. Wear your safety belt even if your car has air bags. ...

  3. Control rod driving hydraulic device

    International Nuclear Information System (INIS)

    Sugano, Hiroshi.

    1993-01-01

    In a control rod driving hydraulic device for an improved BWR type reactor, a bypass pipeline is disposed being branched from a scram pipeline, and a control orifice and a throttle valve are interposed to the bypass pipeline for restricting pressure. Upon occurrence of scram, about 1/2 of water quantity flowing from an accumulator of a hydraulic control unit to the lower surface of a piston of control rod drives by way of a scram pipeline is controlled by the restricting orifice and the throttle valve, by which the water is discharged to a pump suction pipeline or other pipelines by way of the bypass pipeline. With such procedures, a function capable of simultaneously conducting scram for two control rod drives can be attained by one hydraulic control unit. Further, an excessive peak pressure generated by a water hammer phenomenon in the scram pipeline or the control rod drives upon occurrence of scram can be reduced. Deformation and failure due to the excessive peak pressure can be prevented, as well as vibrations and degradation of performance of relevant portions can be prevented. (N.H.)

  4. Virtual Rewards for Driving Green

    Science.gov (United States)

    Pritchard, Josh

    2010-01-01

    Carbon dioxide from automobiles is a major contributor to global climate change. In "Virtual Rewards for Driving Green," Josh Pritchard proposes a computer application that will enable fuel-efficient drivers to earn "green" dollars with which to buy digital merchandise on the Web. Can getting items that exist only in cyberspace actually change a…

  5. Older drivers with cognitive impairment: Perceived changes in driving skills, driving-related discomfort and self-regulation of driving

    DEFF Research Database (Denmark)

    Meng, A.; Siren, A.; Teasdale, Thomas William

    2013-01-01

    The results of a previous study indicate that in general, older drivers who recognise cognitive problems show realistic self-assessment of changes in their driving skills and that driving-related discomfort may function as an indirect monitoring of driving ability, contributing to their safe...... drivers may recognise cognitive problems, they tend not to recognise changes to their driving, which may reflect reluctance to acknowledge the impact of cognitive impairment on their driving. Furthermore, the results suggest that driving-related discomfort plays an important role in the self......-regulation of driving among cognitively impaired older drivers. However, it is less clear what triggers driving-related discomfort among cognitively impaired older drivers indicating that it may be a less reliable aspect of their self-monitoring of driving ability....

  6. 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

  7. Flee or fight: ontogenetic changes in the behavior of cobweb spiders in encounters with spider-hunting wasps.

    Science.gov (United States)

    Uma, Divya B; Weiss, Martha R

    2012-12-01

    An animal's body size plays a predominant role in shaping its interspecific interactions, and, in encounters between two predators, often determines which shall be predator and which shall be prey. Spiders are top predators of insects, yet can fall prey to mud-dauber wasps that provision their larval nests with paralyzed spiders. Here we examined predator-prey interactions between Chalybion californicum (Saussure) (Sphecidae), a mud-dauber wasp, and Parasteatoda tepidariorum C. L. Koch (Theridiidae), a cobweb spider. We examined whether a spider's size influences its response to an attacking wasp, and report a size-dependent change in spider behavior: small-sized spiders fled, whereas medium- and large-sized spiders fought in response to wasp attacks. From the wasps' perspective, we examined whether spider size influences a wasp's hunting behavior and capture success. We found that wasps commonly approached small spiders, but were much less likely to approach medium and large spiders. However, wasp capture success did not vary with spider size. We also report a strategy used by Chalybion wasps toward cobweb spiders that is consistent with an interpretation of aggressive mimicry.

  8. 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

  9. 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

  10. 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

  11. 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

  12. Methanol emissions from maize: Ontogenetic dependence to varying light conditions and guttation as an additional factor constraining the flux

    Science.gov (United States)

    Mozaffar, A.; Schoon, N.; Digrado, A.; Bachy, A.; Delaplace, P.; du Jardin, P.; Fauconnier, M.-L.; Aubinet, M.; Heinesch, B.; Amelynck, C.

    2017-03-01

    Because of its high abundance and long lifetime compared to other volatile organic compounds in the atmosphere, methanol (CH3OH) plays an important role in atmospheric chemistry. Even though agricultural crops are believed to be a large source of methanol, emission inventories from those crop ecosystems are still scarce and little information is available concerning the driving mechanisms for methanol production and emission at different developmental stages of the plants/leaves. This study focuses on methanol emissions from Zea mays L. (maize), which is vastly cultivated throughout the world. Flux measurements have been performed on young plants, almost fully grown leaves and fully grown leaves, enclosed in dynamic flow-through enclosures in a temperature and light-controlled environmental chamber. Strong differences in the response of methanol emissions to variations in PPFD (Photosynthetic Photon Flux Density) were noticed between the young plants, almost fully grown and fully grown leaves. Moreover, young maize plants showed strong emission peaks following light/dark transitions, for which guttation can be put forward as a hypothetical pathway. Young plants' average daily methanol fluxes exceeded by a factor of 17 those of almost fully grown and fully grown leaves when expressed per leaf area. Absolute flux values were found to be smaller than those reported in the literature, but in fair agreement with recent ecosystem scale flux measurements above a maize field of the same variety as used in this study. The flux measurements in the current study were used to evaluate the dynamic biogenic volatile organic compound (BVOC) emission model of Niinemets and Reichstein. The modelled and measured fluxes from almost fully grown leaves were found to agree best when a temperature and light dependent methanol production function was applied. However, this production function turned out not to be suitable for modelling the observed emissions from the young plants

  13. Success in Science, Success in Collaboration

    Energy Technology Data Exchange (ETDEWEB)

    Johnston, Mariann R. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2016-08-25

    This is a series of four different scientific problems which were resolved through collaborations. They are: "Better flow cytometry through novel focusing technology", "Take Off®: Helping the Agriculture Industry Improve the Viability of Sustainable, Large-Production Crops", "The National Institutes of Health's Models of Infectious Disease Agent Study (MIDAS)", and "Expanding the capabilities of SOLVE/RESOLVE through the PHENIX Consortium." For each one, the problem is listed, the solution, advantages, bottom line, then information about the collaboration including: developing the technology, initial success, and continued success.

  14. The Project of Success

    DEFF Research Database (Denmark)

    Kreiner, Kristian

    more complicated matter than meeting targets. While success may ultimately be justified in terms of a correspondence between aims and achievements, the understanding of both aspects is highly dependent on the project process. An example of a successful project that did not meet the original performance...... targets will serve to show that success is at matter of perspective as much as it is a matter of achievement. Other types of research, e.g. social psychology, have addressed the issue of success more explicitly. I draw on such literature to conceptualize project success anew and to reestablish...

  15. Evolution of resistance against CRISPR/Cas9 gene drive

    OpenAIRE

    Clark, Andrew; Unckless, Robert; Messer, Philipp

    2016-01-01

    CRISPR/Cas9 gene drive (CGD) promises to be a highly adaptable approach for spreading genetically engineered alleles throughout a species, even if those alleles impair reproductive success. CGD has been shown to be effective in laboratory crosses of insects, yet it remains unclear to what extent potential resistance mechanisms will affect the dynamics of this process in large natural populations. Here we develop a comprehensive population genetic framework for modeling CGD dynamics, which inc...

  16. 3D MODELING OF DRIVE SHAFT OF A MONORAIL CONVEYOR

    Directory of Open Access Journals (Sweden)

    STĂNĂŞEL Iulian

    2016-11-01

    Full Text Available The conveyors are used to transport various products in successive steps until they reach their destination and to ensure cargo volumes to balance the flow buffer. The conveyors monorail type are used for the transfer of the products, piece by piece and they can be suspended and can operate at heights and different tasks. In this paper is presented a method for the design of the drive shaft of a monorail conveyor, by using CAD-CAE applications.

  17. Methodology for functional MRI of simulated driving.

    Science.gov (United States)

    Kan, Karen; Schweizer, Tom A; Tam, Fred; Graham, Simon J

    2013-01-01

    The developed world faces major socioeconomic and medical challenges associated with motor vehicle accidents caused by risky driving. Functional magnetic resonance imaging (fMRI) of individuals using virtual reality driving simulators may provide an important research tool to assess driving safety, based on brain activity and behavior. A fMRI-compatible driving simulator was developed and evaluated in the context of straight driving, turning, and stopping in 16 young healthy adults. Robust maps of brain activity were obtained, including activation of the primary motor cortex, cerebellum, visual cortex, and parietal lobe, with limited head motion (driving is a feasible undertaking.

  18. Driving Style Analysis Using Primitive Driving Patterns With Bayesian Nonparametric Approaches

    OpenAIRE

    Wang, Wenshuo; Xi, Junqiang; Zhao, Ding

    2017-01-01

    Analysis and recognition of driving styles are profoundly important to intelligent transportation and vehicle calibration. This paper presents a novel driving style analysis framework using the primitive driving patterns learned from naturalistic driving data. In order to achieve this, first, a Bayesian nonparametric learning method based on a hidden semi-Markov model (HSMM) is introduced to extract primitive driving patterns from time series driving data without prior knowledge of the number...

  19. Auto warranty and driving patterns

    International Nuclear Information System (INIS)

    Anastasiadis, Simon; Anderson, Boyd; Chukova, Stefanka

    2013-01-01

    Automobile warranty coverage is typically limited by age as well as mileage. However, the age is known for all sold vehicles at all times, but mileage is only observed for a vehicle with a claim and only at the time of the claim. We study the relationship between the expected number/cost of warranty claims and the driving patterns. Within a nonparametric framework, we account for the rate of mileage accumulation and propose a measure for the variability of this rate over a vehicle's observable life. We illustrate the ideas with real warranty data and comment on the relationship between the expected number/cost of warranty claims and the driving patterns using results adjusted/unadjusted for withdrawals from the warranty coverage due to mileage accumulation

  20. Inside Solid State Drives (SSDs)

    CERN Document Server

    Micheloni, Rino; Eshghi, Kam

    2013-01-01

    Solid State Drives (SSDs) are gaining momentum in enterprise and client applications, replacing Hard Disk Drives (HDDs) by offering higher performance and lower power. In the enterprise, developers of data center server and storage systems have seen CPU performance growing exponentially for the past two decades, while HDD performance has improved linearly for the same period. Additionally, multi-core CPU designs and virtualization have increased randomness of storage I/Os. These trends have shifted performance bottlenecks to enterprise storage systems. Business critical applications such as online transaction processing, financial data processing and database mining are increasingly limited by storage performance. In client applications, small mobile platforms are leaving little room for batteries while demanding long life out of them. Therefore, reducing both idle and active power consumption has become critical. Additionally, client storage systems are in need of significant performance improvement as well ...

  1. Energy intake functions and energy budgets of ectotherms and endotherms derived from their ontogenetic growth in body mass and timing of sexual maturation.

    Science.gov (United States)

    Werner, Jan; Sfakianakis, Nikolaos; Rendall, Alan D; Griebeler, Eva Maria

    2018-05-07

    Ectothermic and endothermic vertebrates differ not only in their source of body temperature (environment vs. metabolism), but also in growth patterns, in timing of sexual maturation within life, and energy intake functions. Here, we present a mathematical model applicable to ectothermic and endothermic vertebrates. It is designed to test whether differences in the timing of sexual maturation within an animal's life (age at which sexual maturity is reached vs. longevity) together with its ontogenetic gain in body mass (growth curve) can predict the energy intake throughout the animal's life (food intake curve) and can explain differences in energy partitioning (between growth, reproduction, heat production and maintenance, with the latter subsuming any other additional task requiring energy) between ectothermic and endothermic vertebrates. With our model we calculated from the growth curves and ages at which species reached sexual maturity energy intake functions and energy partitioning for five ectothermic and seven endothermic vertebrate species. We show that our model produces energy intake patterns and distributions as observed in ectothermic and endothermic species. Our results comply consistently with some empirical studies that in endothermic species, like birds and mammals, energy is used for heat production instead of growth, and with a hypothesis on the evolution of endothermy in amniotes published by us before. Our model offers an explanation on known differences in absolute energy intake between ectothermic fish and reptiles and endothermic birds and mammals. From a mathematical perspective, the model comes in two equivalent formulations, a differential and an integral one. It is derived from a discrete level approach, and it is shown to be well-posed and to attain a unique solution for (almost) every parameter set. Numerically, the integral formulation of the model is considered as an inverse problem with unknown parameters that are estimated using a

  2. Influence of salinity on the larval development of the fiddler crab Uca vocator (Ocypodidae) as an indicator of ontogenetic migration towards offshore waters

    Science.gov (United States)

    de Jesus de Brito Simith, Darlan; de Souza, Adelson Silva; Maciel, Cristiana Ramalho; Abrunhosa, Fernando Araújo; Diele, Karen

    2012-03-01

    Larvae of many marine decapod crustaceans are released in unpredictable habitats with strong salinity fluctuations during the breeding season. In an experimental laboratory study, we investigated the influence of seven different salinities (0, 5, 10, 15, 20, 25 and 30) on the survival and development time of fiddler crab zoea larvae, Uca vocator, from northern Brazilian mangroves. The species reproduces during the rainy season when estuarine salinity strongly fluctuates and often reaches values below 10 and even 5. Salinity significantly affected the survival rate and development period from hatching to megalopa, while the number of zoeal stages remained constant. In salinities 0 and 5, no larvae reached the second zoeal stage, but they managed to survive for up to 3 (average of 2.3 days) and 7 days (average of 5.1 days), respectively. From salinity 10 onwards, the larvae developed to the megalopal stage. However, the survival rate was significantly lower (5-15%) and development took more time (average of 13.5 days) in salinity 10 than in the remaining salinities (15-30). In the latter, survival ranged from 80-95% and development took 10-11 days. Given the 100% larval mortality in extremely low salinities and their increased survival in intermediate and higher salinities, we conclude that U. vocator has a larval `export' strategy with its larvae developing in offshore waters where salinity conditions are more stable and higher than in mangrove estuaries. Thus, by means of ontogenetic migration, osmotic stress and resulting mortality in estuarine waters can be avoided.

  3. A model explaining genotypic and ontogenetic variation of leaf photosynthetic rate in rice (Oryza sativa) based on leaf nitrogen content and stomatal conductance.

    Science.gov (United States)

    Ohsumi, Akihiro; Hamasaki, Akihiro; Nakagawa, Hiroshi; Yoshida, Hiroe; Shiraiwa, Tatsuhiko; Horie, Takeshi

    2007-02-01

    Identification of physiological traits associated with leaf photosynthetic rate (Pn) is important for improving potential productivity of rice (Oryza sativa). The objectives of this study were to develop a model which can explain genotypic variation and ontogenetic change of Pn in rice under optimal conditions as a function of leaf nitrogen content per unit area (N) and stomatal conductance (g(s)), and to quantify the effects of interaction between N and g(s) on the variation of Pn. Pn, N and g(s) were measured at different developmental stages for the topmost fully expanded leaves in ten rice genotypes with diverse backgrounds grown in pots (2002) and in the field (2001 and 2002). A model of Pn that accounts for carboxylation and CO diffusion processes, and assumes that the ratio of internal conductance to g(s) is constant, was constructed, and its goodness of fit was examined. Considerable genotypic differences in Pn were evident for rice throughout development in both the pot and field experiments. The genotypic variation of Pn was correlated with that of g(s) at a given stage, and the change of Pn with plant development was closely related to the change of N. The variation of g(s) among genotypes was independent of that of N. The model explained well the variation in Pn of the ten genotypes grown under different conditions at different developmental stages. Conclusions The response of Pn to increased N differs with g(s), and the increase in Pn of genotypes with low g(s) is smaller than that of genotypes with high g(s). Therefore, simultaneous improvements of these two traits are essential for an effective breeding of rice genotypes with increased Pn.

  4. Ontogenetic behavior, migration, and social behavior of pallid sturgeon, Scaphirhynchus albus, and shovelnose sturgeon, S. platorynchus, with notes on the adaptive significance of body color

    Science.gov (United States)

    Kynard, B.; Henyey, E.; Horgan, M.

    2002-01-01

    We conducted laboratory studies on the ontogenetic behavior of free embryos (first life interval after hatching) and larvae (first feeding interval) of pallid and shovelnose sturgeon. Migration styles of both species were similar for timing of migration (initiation by embryos on day 0 after hatching and cessation by larvae on days 12-13 at 236-243 cumulative temperature degree units), migration distance (about 13 km), life interval when most distance was moved (embryo), and diel behavior of embryos (diurnal). However, the species differed for two behaviors: movement characteristics of embryos (peak movement rate of pallid sturgeon was only one-half the peak rate of shovelnose sturgeon, but pallid sturgeon continued the lower rate for twice as long) and diel behavior of larvae (pallid sturgeon were diurnal and shovelnose sturgeon were nocturnal). Thus, the species used different methods to move the same distance. Migrating as poorly developed embryos suggests a migration style to avoid predation at the spawning site, but moving from spawning habitat to rearing habitat before first feeding could also be important. Migrants of both species preferred bright habitat (high illumination intensity and white substrate), a behavioral preference that may characterize the migrants of many species of sturgeon. Both species were remarkably similar for swimming height above the bottom by age, and day 7 and older migrants may swim far above the bottom and move far downstream. A migration of 12 or 13 days will probably not distribute larvae throughout the population's range, so an older life interval likely initiates a second longer downstream migration (2-step migration). By day 2, individuals of both species were a black-tail phenotype (light grey body with a black-tail that moved conspicuously during swimming). Aggregation behavior suggests that black-tail is a visual signal used for group cohesion.

  5. Early decrease in dietary protein:energy ratio by fat addition and ontogenetic changes in muscle growth mechanisms of rainbow trout: short- and long-term effects.

    Science.gov (United States)

    Alami-Durante, Hélène; Cluzeaud, Marianne; Duval, Carine; Maunas, Patrick; Girod-David, Virginia; Médale, Françoise

    2014-09-14

    As the understanding of the nutritional regulation of muscle growth mechanisms in fish is fragmentary, the present study aimed to (1) characterise ontogenetic changes in muscle growth-related genes in parallel to changes in muscle cellularity; (2) determine whether an early decrease in dietary protein:energy ratio by fat addition affects the muscle growth mechanisms of rainbow trout (Oncorhynchus mykiss) alevins; and (3) determine whether this early feeding of a high-fat (HF) diet to alevins had a long-term effect on muscle growth processes in juveniles fed a commercial diet. Developmental regulation of hyperplasia and hypertrophy was evidenced at the molecular (expression of myogenic regulatory factors, proliferating cell nuclear antigen and myosin heavy chains (MHC)) and cellular (number and diameter of white muscle fibres) levels. An early decrease in dietary protein:energy ratio by fat addition stimulated the body growth of alevins but led to a fatty phenotype, with accumulation of lipids in the anterior part, and less caudal muscle when compared at similar body weights, due to a decrease in both the white muscle hyperplasia and maximum hypertrophy of white muscle fibres. These HF diet-induced cellular changes were preceded by a very rapid down-regulation of the expression of fast-MHC. The present study also demonstrated that early dietary composition had a long-term effect on the subsequent muscle growth processes of juveniles fed a commercial diet for 3 months. When compared at similar body weights, initially HF diet-fed juveniles indeed had a lower mean diameter of white muscle fibres, a smaller number of large white muscle fibres, and lower expression levels of MyoD1 and myogenin. These findings demonstrated the strong effect of early feed composition on the muscle growth mechanisms of trout alevins and juveniles.

  6. Extended mesometrial resection (EMMR): Surgical approach to the treatment of locally advanced cervical cancer based on the theory of ontogenetic cancer fields.

    Science.gov (United States)

    Wolf, Benjamin; Ganzer, Roman; Stolzenburg, Jens-Uwe; Hentschel, Bettina; Horn, Lars-Christian; Höckel, Michael

    2017-08-01

    Based on ontogenetic-anatomic considerations, we have introduced total mesometrial resection (TMMR) and laterally extended endopelvic resection (LEER) as surgical treatments for patients with cancer of the uterine cervix FIGO stages I B1 - IV A. For a subset of patients with locally advanced disease we have sought to develop an operative strategy characterized by the resection of additional tissue at risk for tumor infiltration as compared to TMMR, but less than in LEER, preserving the urinary bladder function. We conducted a prospective single center study to evaluate the feasibility of extended mesometrial resection (EMMR) and therapeutic lymph node dissection as a surgical treatment approach for patients with cervical cancer fixed to the urinary bladder and/or its mesenteries as determined by intraoperative evaluation. None of the patients received postoperative adjuvant radiotherapy. 48 consecutive patients were accrued into the trial. Median tumor size was 5cm, and 85% of all patients were found to have lymph node metastases. Complete tumor resection (R0) was achieved in all cases. Recurrence free survival at 5years was 54.1% (95% CI 38.3-69.9). The overall survival rate was 62.6% (95% CI 45.6-79.6) at 5years. Perioperative morbidity represented by grade II and III complications (determined by the Franco-Italian glossary) occurred in 25% and 15% of patients, respectively. We demonstrate in this study the feasibility of EMMR as a surgical treatment approach for patients with locally advanced cervical cancer and regional lymph node invasion without the necessity for postoperative adjuvant radiation. Copyright © 2017 Elsevier Inc. All rights reserved.

  7. Supporting Success for All Students

    Science.gov (United States)

    Manduca, C. A.; Macdonald, H.; McDaris, J. R.; Weissmann, G. S.

    2015-12-01

    The geoscience student population in the United States today does not reflect the diversity of the US population. Not only does this challenge our ability to educate sufficient numbers of students in the geosciences, it also challenges our ability to address issues of environmental justice, to bring geoscience expertise to diverse communities, and to pursue a research agenda reflecting the needs and interests of our nation as a whole. Programs that are successful in supporting students from underrepresented groups attend to the whole student (Jolly et al, 2004) as they develop not only knowledge and skills, but a sense of belonging and a drive to succeed in geoscience. The whole student approach provides a framework for supporting the success of all students, be they members of underrepresented groups or not. Important aspects of support include mentoring and advising, academic support, an inclusive learning community, and opportunities to learn about the profession and to develop geoscience and professional skills. To successfully provide support for the full range of students, it is critical to consider not only what opportunities are available but the barriers different types of students face in accessing these opportunities. Barriers may arise from gaps in academic experiences, crossing into a new and unfamiliar culture, lack of confidence, stereotype threat, implicit bias and other sources. Isolation of geoscience learning from its application and social context may preferentially discourage some groups. Action can be taken to increase support for all students within an individual course, a department or an institution. The InTeGrate STEP Center for the Geosciences, the Supporting and Advancing Geoscience Education at Two-Year Colleges program and the On the Cutting Edge Professional Development for Geoscience Faculty program all provide resources for individuals and departments including on line information, program descriptions, and workshop opportunities.

  8. Low frequency rf current drive

    International Nuclear Information System (INIS)

    Hershkowitz, N.

    1992-01-01

    An unshielded antenna for rf heating has been developed and tested during this report period. In addition to design specifications being given, some experimental results are presented utilizing: (1) an unprotected Faraday shield, (2) insulating guard limiters, (3) unshielded antenna experiments, (4) method for detecting small rf driven currents, (5) rf fast wave current drive experiments, (6) alfven wave interactions with electrons, and (7) machine conditioning, impurity generation and density control

  9. FOREIGN DRIVING LICENCES IN FRANCE

    CERN Multimedia

    Service des relations avec les Pays Hôtes

    2000-01-01

    1. PERSONS RESIDING IN FRANCE1.1 National driving licences from countries belonging to the EEAa) ValidityCurrent national driving licences issued by a country belonging to the European Economic Area (here inafter called EEA) are, in principle, valid in France. N.B. : The countries belonging to the EEA are Austria, Belgium, Denmark, Finland, France, Germany, Greece, Iceland, Ireland, Italy, Liechtenstein, Luxembourg, Netherlands, Norway, Portugal, Spain, Sweden and the United Kingdom.b)\tRegistrationTo ensure that all the conditions of validity in France have been met, holders of driving licences issued by a country belonging to the EEA, who reside in France (i.e. hold a residence permit issued by a Préfecture, or a carte spéciale issued by the French Ministry of Foreign Affairs, which is equivalent to a residence permit), can have their licences registered with the Préfecture of the department where they live (for Ain, call 04 74 32 30 00, for Haute Savoie call 04 50 33 ...

  10. Factors That Drive Youth Specialization.

    Science.gov (United States)

    Padaki, Ajay S; Popkin, Charles A; Hodgins, Justin L; Kovacevic, David; Lynch, Thomas Sean; Ahmad, Christopher S

    Specialization in young athletes has been linked to overuse injuries, burnout, and decreased satisfaction. Despite continued opposition from the medical community, epidemiological studies suggest the frequency is increasing. Extrinsic pressures in addition to individual aspirations drive this national trend in sports specialization. Descriptive epidemiology study. Level 3. A novel instrument assessing the driving factors behind youth specialization was generated by an interdisciplinary team of medical professionals. Surveys were administered to patients and athletes in the department's sports medicine clinic. The survey was completed by 235 athletes between 7 and 18 years of age, with a mean age of 13.8 ± 3.0 years. Athletes specialized at a mean age of 8.1 years, and 31% of athletes played a single sport while 58% played multiple sports but had a preferred sport. More than 70% of athletes had collegiate or professional ambitions, and 60% played their primary sport for 9 or more months per year, with players who had an injury history more likely to play year-round ( P specialized athletes reporting this significantly more often ( P = 0.04). Half of the athletes reported that sports interfered with their academic performance, with older players stating this more frequently ( P specializing in a single sport before starting high school. While intrinsic drive may identify healthy aspirations, extrinsic influences are prevalent in specialized athletes. Extrinsic factors contributing to youth specialization were identified and compounded the deleterious sequelae of youth athlete specialization.

  11. Foreign driving licences in Switzerland

    CERN Multimedia

    2009-01-01

    1. Persons residing in Switzerland 1.1 Holders of a B, C, D, E or P-type "carte de légitimation" For holders of a B, C, D, E or P-type "carte de légitimation" issued by the Swiss Federal Department for Foreign Affairs (DFAE), current non-Swiss national driving licences are valid in Switzerland. (see the official news about the new "Carte de légitimation P") If they so wish, holders of such driving licences may apply to the relevant road licensing authority in the canton where they live (Service des Automobiles et de la Navigation; for Geneva call + 41 22 388 30 30, website http://www.geneve.ch/san; for Vaud call + 41 21 316 82 10, website http://www.san.vd.ch/index.html) to exchange their driving licence for an equivalent Swiss licence (they must pass a test if they are not citizens of countries with which Switzerland has concluded an agreement on this matter, e.g. Member States of the European Union, the United States and Japan). However, such an exchange is not possible...

  12. Foreign driving licences in France

    CERN Multimedia

    HR Department

    2009-01-01

    The following information is subject to possible amendments decided by the competent French authorities. Those wishing to undertake the necessary steps with the prefectural services of the Departments of the Ain and Haute-Savoie may obtain information by calling the following numbers: + 33 4 74 32 30 65 for the Ain and + 33 4 50 33 60 00 for Haute-Savoie. 1. PERSONS RESIDING IN FRANCE 1.1 Driving licences issued by a State belonging to the EU or the EEA a) Recognition on French territory All currently valid driving licences issued by States belonging to the European Union (EU) or to the European Economic Area (EEA) are generally valid for driving on French territory. However, if the licence was originally obtained in exchange for a licence issued by a State not belonging to the EU or to the EEA and with which France has not concluded a reciprocity agreement, it will be recognised for a maximum of one year following the date of establishment of normal residence in France ...

  13. FOREIGN DRIVING LICENCES IN FRANCE

    CERN Multimedia

    DSU Unit

    2008-01-01

    The following information is provided subject to possible amendments decided by the competent French authorities. Those wishing to undertake the necessary steps with the prefectural services of the Departments of Ain and Haute-Savoie may obtain information by calling the following numbers: + 33 474 32 30 65 for Ain and + 33 450 33 60 00 for Haute-Savoie. 1. PEOPLE RESIDING IN FRANCE 1.1 Driving licences issued by a state belonging to the EU or the EEA a) Recognition on French territory All currently valid driving licences issued by States belonging to the European Union (EU) or to the European Economic Area (EEA) are generally valid for driving on French territory. However, if the licence was originally obtained in exchange for a licence issued by a State not belonging to the EU or to the EEA with which France has not concluded a reciprocity agreement, it is recognised only up to one year following the date of establishment of normal residence in France (date of the first special residence permit issu...

  14. Implicit attitudes towards risky and safe driving

    DEFF Research Database (Denmark)

    Martinussen, Laila Marianne; Sømhovd, Mikael Julius; Møller, Mette

    ; further, self-reports of the intention to drive safely (or not) are socially sensitive. Therefore, we examined automatic preferences towards safe and risky driving with a Go/No-go Association Task (GNAT). The results suggest that (1) implicit attitudes towards driving behavior can be measured reliably...... with the GNAT; (2) implicit attitudes towards safe driving versus towards risky driving may be separable constructs. We propose that research on driving behavior may benefit from routinely including measures of implicit cognition. A practical advantage is a lesser susceptibility to social desirability biases......, compared to self-report methods. Pending replication in future research, the apparent dissociation between implicit attitudes towards safe versus risky driving that we observed may contribute to a greater theoretical understanding of the causes of unsafe and risky driving behavior....

  15. 77 FR 61048 - Distracted Driving Grant Program

    Science.gov (United States)

    2012-10-05

    ... DEPARTMENT OF TRANSPORTATION National Highway Traffic Safety Administration Distracted Driving Grant Program AGENCY: National Highway Traffic Safety Administration (NHTSA), Department of... distracted driving grants on August 24, 2012. In this notice, DOT is extending the application submission...

  16. Low Vision Driving with Bioptics: An Overview

    Science.gov (United States)

    Huss, Chuck; Corn, Anne

    2004-01-01

    This article presents an overview of driving for adolescents and adults who meet their states' visual requirements for low vision driving using bioptic lenses. It also discusses the outcomes of two studies of bioptic driver education.

  17. Advisory and autonomous cooperative driving systems

    NARCIS (Netherlands)

    Broek, T.H.A. van den; Ploeg, J.; Netten, B.D.

    2011-01-01

    In this paper, the traffic efficiency of an advisory cooperative driving system, Advisory Acceleration Control is examined and compared to the efficiency of an autonomous cooperative driving system, Cooperative Adaptive Cruise Control. The algorithms and implementation thereof are explained. The

  18. Business Intelligence Success Factors

    DEFF Research Database (Denmark)

    Gaardboe, Rikke; Jonasen, Tanja Svarre

    2018-01-01

    Business intelligence (BI) is a strategically important practice in many organizations. Several studies have investigated the factors that contribute to BI success; however, an overview of the critical success factors (CSFs) involved is lacking in the extant literature. We have integrated...... 34 CSFs related to BI success. The distinct CSFs identified in the extant literature relate to project management skills (13 papers), management support (20 papers), and user involvement (11 papers). In the articles with operationalized BI success, we found several distinct factors: system quality...

  19. Driving When You Have Parkinson's Disease

    Science.gov (United States)

    Driving When You Have Parkinson’s Disease DRIVEWELL You have been a safe driver for years. For you, driving means freedom and control. As you get ... mental health can affect how safely you drive. Parkinson’s disease is a disorder of the central nervous ...

  20. 77 FR 51610 - Distracted Driving Grant Program

    Science.gov (United States)

    2012-08-24

    .... (2) Prohibition on youth cell phone use while driving. The State statute must-- (a) Prohibit a driver... of texting or using a cell phone while driving; (2) for traffic signs that notify drivers about the... DEPARTMENT OF TRANSPORTATION National Highway Traffic Safety Administration Distracted Driving...

  1. Advanced health monitor for automated driving functions

    OpenAIRE

    Mikovski Iotov, I.

    2017-01-01

    There is a trend in the automotive domain where driving functions are taken from the driver by automated driving functions. In order to guarantee the correct behavior of these auto-mated driving functions, the report introduces an Advanced Health Monitor that uses Tem-poral Logic and Probabilistic Analysis to indicate the system’s health.

  2. Advanced health monitor for automated driving functions

    NARCIS (Netherlands)

    Mikovski Iotov, I.

    2017-01-01

    There is a trend in the automotive domain where driving functions are taken from the driver by automated driving functions. In order to guarantee the correct behavior of these auto-mated driving functions, the report introduces an Advanced Health Monitor that uses Tem-poral Logic and Probabilistic

  3. Modeling human learning involved in car driving

    NARCIS (Netherlands)

    Wewerinke, P.H.

    1994-01-01

    In this paper, car driving is considered at the level of human tracking and maneuvering in the context of other traffic. A model analysis revealed the most salient features determining driving performance and safety. Learning car driving is modelled based on a system theoretical approach and based

  4. Cooperative driving in platooning scenario’s

    NARCIS (Netherlands)

    van der Linden, M.J.G.M.; Nijmeijer, H.

    2011-01-01

    Cooperative driving enables a more efficient use of existing infrastructure which reduces the expenditures and land use for new roads. Cooperative driving is based on intelligent communication between vehicles and between vehicles and their environment. Vehicles can drive closer to each other due to

  5. Adjustable Speed Drives - Future Challenges and Applications

    DEFF Research Database (Denmark)

    Blaabjerg, Frede; Thoegersen, Paul

    2004-01-01

    The main trends within Adjustable Drives in industrial and appliance applications for the next decade are discussed based on the newest developments seen on the market and a few historical trends. Different drive configurations are presented and the general demands to adjustable speed drives...

  6. Characterizing on-road driving performance in individuals with traumatic brain injury who pass or fail an on-road driving assessment.

    Science.gov (United States)

    Stolwyk, Renerus J; Charlton, Judith L; Ross, Pamela E; Bédard, Michel; Marshall, Shawn; Gagnon, Sylvain; Gooden, James R; Ponsford, Jennie L

    2018-01-15

    with observation, speed regulation, gap selection, and vehicle control and accordingly had difficulty executing a diverse range of common driving manoeuvres. Comprehensive, formal on-road assessments, incorporating a range of skills, and manoeuvres, are needed to evaluate readiness to return to driving following traumatic brain injury. Individually tailored driver rehabilitation programs need to address these heterogeneous skill deficits to best support individuals to make a successful return to driving post-traumatic brain injury.

  7. Driving patterns in older adults with glaucoma.

    Science.gov (United States)

    van Landingham, Suzanne W; Hochberg, Chad; Massof, Robert W; Chan, Emilie; Friedman, David S; Ramulu, Pradeep Y

    2013-02-21

    The ability to drive is important for ensuring quality of life for many older adults. Glaucoma is prevalent in this age group and may affect driving. The purpose of this study is to determine if glaucoma and glaucomatous visual field (VF) loss are associated with driving cessation, limitations, and deference to another driver in older adults. Cross-sectional study. Eighty-one glaucoma subjects and 58 glaucoma suspect controls between age 60 and 80 reported if they had ceased driving, limited their driving in various ways, or preferred another to drive. Twenty-three percent of glaucoma subjects and 6.9% of suspects had ceased driving (p = 0.01). Glaucoma subjects also had more driving limitations than suspects (2.0 vs. 1.1, p = 0.007). In multivariable models, driving cessation was more likely for glaucoma subjects as compared to suspects (OR = 4.0; 95% CI = 1.1-14.7; p = 0.03). The odds of driving cessation doubled with each 5 decibel (dB) decrement in the better-eye VF mean deviation (MD) (OR = 2.0; 95% CI = 1.4-2.9; p driving limitations (OR = 4.7; 95% CI = 1.3-16.8; p = 0.02). The likelihood of reporting more limitations increased with the VF loss severity (OR = 1.6 per 5 dB decrement in the better-eye VF MD; 95% CI = 1.1-2.4; p = 0.02). Neither glaucoma nor VF MD was associated with other driver preference (p > 0.1 for both). Glaucoma and glaucomatous VF loss are associated with greater likelihood of driving cessation and greater limitation of driving in the elderly. Further prospective study is merited to assess when and why people with glaucoma change their driving habits, and to determine if their observed self-regulation of driving is adequate to ensure safety.

  8. Depression, antidepressants and driving safety.

    Science.gov (United States)

    Hill, Linda L; Lauzon, Vanessa L; Winbrock, Elise L; Li, Guohua; Chihuri, Stanford; Lee, Kelly C

    2017-12-01

    The purpose of this study was to review to review the reported associations of depression and antidepressants with motor vehicle crashes. A literature search for material published in the English language between January, 1995, and October, 2015, in bibliographic databases was combined with a search for other relevant material referenced in the retrieved articles. Retrieved articles were systematically reviewed for inclusion criteria: 19 epidemiological studies (17 case-control and 2 cohort studies) fulfilled the inclusion criteria by estimating the crash risk associated with depression and/or psychotropic medications in naturalistic settings. The estimates of the odds ratio (OR) of crash involvement associated with depression ranged from 1.78 to 3.99. All classes of antidepressants were reported to have side effects with the potential to affect driving safety. The majority of studies of antidepressant effects on driving reported an elevated crash risk, and ORs ranged from 1.19 to 2.03 for all crashes, and 3.19 for fatal crashes. In meta-analysis, depression was associated with approximately 2-fold increased crash risk (summary OR = 1.90; 95% CI, 1.06 to 3.39), and antidepressants were associated with approximately 40% increased crash risk (summary OR = 1.40; 95%CI, 1.18 to 1.66). Based on the findings of the studies reviewed, depression, antidepressants or the combination of depression and antidepressants may pose a potential hazard to driving safety. More research is needed to understand the individual contributions of depression and the medications used to treat depression.

  9. Examining Management Success Potential.

    Science.gov (United States)

    Quatrano, Louis A.

    The derivation of a model of management success potential in hospitals or health services administration is described. A questionnaire developed to assess management success potential in health administration students was voluntarily completed by approximately 700 incoming graduate students in 35 university health services administration programs…

  10. Ingredients for successful partnerships

    NARCIS (Netherlands)

    S.M. Pfisterer (Stella)

    2011-01-01

    textabstractFor the development of new cross-sector partnerships it is required to know what the essence of successful partnership projects is. Which factors influence success or failure of partnerships is highly related to the specific context where partnerships operate. The literature on critical

  11. Human Resource Outsourcing Success

    OpenAIRE

    Hasliza Abdul-Halim; Elaine Ee; T. Ramayah; Noor Hazlina Ahmad

    2014-01-01

    The existing literature on partnership seems to take the relationship between partnership quality and outsourcing success for granted. Therefore, this article aims at examining the role of service quality in strengthening the relationship between partnership quality and human resource (HR) outsourcing success. The samples were obtained from 96 manufacturing organizations in Penang, Malaysia. The results showed that par...

  12. Planning for College Success

    Science.gov (United States)

    PEPNet, 2009

    2009-01-01

    "Planning for College Success" (PCS) is a curriculum model designed by Sharon Downs, M.S., for a course intended to assist deaf and hard of hearing students during their initial introduction to college life. This program allows students to work one-on-one with a counselor to plan for their college success. The program includes short-term goals and…

  13. Driving safety and adolescent behavior.

    Science.gov (United States)

    Brown, R C; Sanders, J M; Schonberg, S K

    1986-04-01

    Accidents, and mainly automotive accidents, are currently the leading cause of mortality and morbidity among young people. Understanding and addressing the issue of automotive accident prevention requires an awareness of the multiple psychodynamic, familial, and societal influences that affect the development and behavior of adolescents. Risk-taking behavior is the product of complex personal and environmental factors. As pediatricians, we have the obligation and the opportunity to improve the safety of our youth who drive and ride. This opportunity is available to us not only in our roles as counselors to youth and families, but also as we serve as role models, educators, and agents for change within our communities.

  14. Motor Integrated Variable Speed Drives

    DEFF Research Database (Denmark)

    Singh, Yash Veer

    rectifier at the front end is presented in this thesis and requirements of a buffer stage in the form of ESI is explained in detail. An equivalent circuit and linear model are developed to give the transfer function and control of the ESI based three-phase rectifier. In this thesis a power converter...... with ESI is designed and tested with standard induction motor to verify functionality of a working drive. One modified version of the ESI based converter has also been looked into to reduce losses of converter, but because of difficulties in reducing the bus-bar inductance in that design, further...

  15. Heavy consumption and drink driving

    DEFF Research Database (Denmark)

    Fynbo, Lars

    2010-01-01

    This paper is part of an ongoing mixed methods project about untreated heavy alcohol consumption amongst adult Danes. It is based upon 21 in-depth qualitative interviews with convicted drink drivers. All interviewees were contacted while attending mandatory courses in “Alcohol and Traffic safety...... on the interviewee’s risk behaviour, especially in relation to driving. The interviewees are first divided into 1) a group of young “edgeworkers” with pronounced general risk behaviour, 2) a group of middle-aged “post-edgeworkers”, most with criminal records, and 3) a group of middle-aged and older heavy consumers...

  16. The impact of continuous driving time and rest time on commercial drivers' driving performance and recovery.

    Science.gov (United States)

    Wang, Lianzhen; Pei, Yulong

    2014-09-01

    This real road driving study was conducted to investigate the effects of driving time and rest time on the driving performance and recovery of commercial coach drivers. Thirty-three commercial coach drivers participated in the study, and were divided into three groups according to driving time: (a) 2 h, (b) 3 h, and (c) 4 h. The Stanford Sleepiness Scale (SSS) was used to assess the subjective fatigue level of the drivers. One-way ANOVA was employed to analyze the variation in driving performance. The statistical analysis revealed that driving time had a significant effect on the subjective fatigue and driving performance measures among the three groups. After 2 h of driving, both the subjective fatigue and driving performance measures began to deteriorate. After 4 h of driving, all of the driving performance indicators changed significantly except for depth perception. A certain amount of rest time eliminated the negative effects of fatigue. A 15-minute rest allowed drivers to recover from a two-hour driving task. This needed to be prolonged to 30 min for driving tasks of 3 to 4 h of continuous driving. Drivers' attention, reactions, operating ability, and perceptions are all affected in turn after over 2 h of continuous driving. Drivers should take a certain amount of rest to recover from the fatigue effects before they continue driving. Copyright © 2014 National Safety Council and Elsevier Ltd. All rights reserved.

  17. Perceptual and Cognitive Impairments and Driving

    Science.gov (United States)

    Korner-Bitensky, Nicol; Coopersmith, Henry; Mayo, Nancy; Leblanc, Ginette; Kaizer, Franceen

    1990-01-01

    Perceptual and cognitive disorders that frequently accompany stroke and head injury influence an individual's ability to drive a motor vehicle. Canadian physicians are legally responsible for identifying patients who are potentially unsafe to drive and, if they fail to do so, may be held liable in a civil action suit. The authors review the guidelines for physicians evaluating a patient's fitness to drive after brain injury. They also examine the actions a physician should take when a patient with perceptual and cognitive problems wants to drive. Ultimately, by taking these actions, physicians will help to prevent driving accidents. PMID:21234047

  18. Mergers: Success versus failure

    International Nuclear Information System (INIS)

    Carley, G. R.

    1997-01-01

    Successful mergers in the context of long-term value creation, as measured by return realized on investor-provided capital, were discussed. In essence, a successful merger is characterized by being motivated by a sound business reason and strategy for the merger, a reasonable price and sound execution. The acquiror's pre-merger success in managing a company is a good indicator of future success. Poorly managed companies that acquire other companies generally continue to be poorly managed with no significant increase in shareholder value. Prior to the acquisition, identification of the potential target, assessment of the people involved on both sides of the transaction, thorough knowledge of the target's potential for value creation, financial implications (debt, equity, terms and demand, tax implications, the potential effect of the proposed acquisition on the acquiror's business plan) and finally the execution of the process itself, are the important determinants of successful mergers

  19. Smartphone Based Approach For Monitoring Inefficient And Unsafe Driving Behavior And Recognizing Drink And Drive Conditions.

    Directory of Open Access Journals (Sweden)

    G. V. Mane

    2015-08-01

    Full Text Available Many automobile drivers having knowledge of the driving behaviours and habits that can lead to inefficient and unsafe driving. However it is often the case that these same drivers unknowingly manifest these inefficient and unsafe driving behaviours in their everyday driving activity. The proposed system proposes a practical and economical way to capture measure and alert drives of inefficient and unsafe driving as well as highly efficient system aimed at early detection and alert of dangerous vehicle maneuvers typically related to drunk driving. The upcoming solution consists of a mobile application running on a modern smartphone device paired with a compatible OBDII On-board diagnostics II reader.

  20. Driving factors for the regional implementation of renewable energy ‐ A multiple case study on the German energy transition

    International Nuclear Information System (INIS)

    Lutz, Lotte Marie; Fischer, Lisa-Britt; Newig, Jens; Lang, Daniel Johannes

    2017-01-01

    Understanding what drives the regional implementation of renewable energy is a prerequisite for energy transitions toward a post-fossil-based energy economy. This paper presents an empirical analysis of driving factors for the regional implementation and use of renewable energy. We tested literature-derived driving factors in a comparative analysis of 18 selected study regions using Rough Set Analysis and performance analysis. We paid special attention to common combinations of driving factors, which we understand as established practices concerning the use and implementation of renewable energy. Our findings confirm most of the driving factors identified in the literature, for example the existence of key actors, knowledge exchange, or the use of goals and milestones. We also observe differences in key driving factors between highly successful and less successful regions, especially regarding funding opportunities. The results may support policy makers who aim to successfully implement renewable energy at a regional level. - Highlights: • We analyzed driving factors for RE implementation in 18 best-practice regions. • Most driving factors from transition and governance literature were confirmed. • We identified common successful practices concerning RE implementation.

  1. Measuring device for control rod driving time

    International Nuclear Information System (INIS)

    Tanaka, Kazuhiko; Hanabusa, Masatoshi.

    1993-01-01

    The present invention concerns a measuring device for control driving time having a function capable of measuring a selected control rod driving time and measuring an entire control rod driving time simultaneously. A calculation means and a store means for the selected rod control rod driving time, and a calculation means and a store means for the entire control rod driving time are disposed individually. Each of them measures the driving time and stores the data independent of each other based on a selected control rod insert ion signal and an entire control rod insertion signal. Even if insertion of selected and entire control rods overlaps, each of the control rod driving times can be measured reliably to provide an advantageous effect capable of more accurately conducting safety evaluation for the nuclear reactor based on the result of the measurement. (N.H.)

  2. Differential invasion success of salmonids in southern Chile: patterns and hypotheses

    Science.gov (United States)

    Ivan Arismendi; Brooke E. Penaluna; Jason B. Dunham; Carlos Garcia de Leaniz; Doris Soto; Ian A. Fleming; Daniel Gomez-Uchida; Gonzalo Gajardo; Pamela V. Varga; Jorge León-Muñoz

    2014-01-01

    Biological invasions create complex ecological and societal issues worldwide. Most of the knowledge about invasions comes only from successful invaders, but less is known about which processes determine the differential success of invasions. In this review, we develop a framework to identify the main dimensions driving the success and failure of invaders, including...

  3. Electrohydraulic drive system with planetary superposed PS 16 gears

    Energy Technology Data Exchange (ETDEWEB)

    Graetz, A.; Klimek, K.H.; Welz, H.

    1988-10-20

    During the nine-month period of use of the electrohydraulic drive system with PS 16 superposed planetary gear and hydrostatic support advance of 800 m was achieved on the 250 m long face in the Geitling 2 seam at the Niederberg colliery. No appreciable difficulties occurred in the hydraulic system and with the PS 16 superposed planetary gear in the entire period. Uniform load distribution between the two drives was proved until the end of the working even with a chain elongation difference up to 3% observed during the final phase of operation. In contrast to normal operation thermal disconnections and motor failures no longer occurred. After accurate adjustment of the pressures the system operated successfully. The time utilisation of the equipment was improved by 15% to 65.7%. The quick and reliable response of the hydraulics in the event of overloading ensured that no chain cracks occurred. The four connector fractures were attributable to fatigue failures. The material-protecting method of operation was proved by the quiet running of the chain and substantially longer operating time, e.g. of the chain and sprocket. To prove the efficiency of the new drive system, comprehensive measurements were undertaken. It emerged during these measurements that in contrast to the conventional drives the load equalisation ensures that the total installed power is available if required. However, the freeing capacity of the plough could not be fully utilised because of the missing conveyor cross-section.

  4. Open-wheel race car driving: energy cost for pilots.

    Science.gov (United States)

    Beaune, Bruno; Durand, Sylvain; Mariot, Jean-Pierre

    2010-11-01

    The aim of this study was to evaluate the energy cost of speedway open-wheel race car driving using actimetry. Eight pilot students participated in a training session consisting of 5 successive bouts of around 30 minutes driving at steady speed on the Bugatti speedway of Le Mans (France). Energy expenditure (EE, kcal) was determined continuously by the actimetric method using the standard equation. Energy cost was estimated through physical activity ratio (PAR = EE/BMR ratio, Mets) calculation after basal metabolism rate (BMR, kcal·min-1) estimation. A 1-met PAR value was attributed to the individual BMR of each volunteer. Bout durations and EE were not significantly different between driving bouts. Mean speed was 139.94 ± 2.96 km·h-1. Physical activity ratio values ranged 4.92 ± 0.50 to 5.43 ± 0.47 Mets, corresponding to a 5.27 ± 0.47-Mets mean PAR values and a 1.21 ± 0.41 kcal·min-1 mean BMR value. These results suggest that actimetry is a simple and efficient method for EE and PAR measurements in motor sports. However, further studies are needed in the future to accurately evaluate relationships between PAR and driving intensity or between PAR and race car type.

  5. Computer Security: drive-bye

    CERN Multimedia

    Stefan Lueders, Computer Security Team

    2016-01-01

    Like a lion waiting to ambush gazelles at a waterhole, malware can catch you by surprise.    As some of you might have noticed, the Computer Security Team had to block the news site “20min.ch” a while ago, as it was found to be distributing malware. This block comes after similar incidents at other Swiss organizations. Our blocking is protective in order to safeguard your computers, laptops, tablets and smartphones. Unfortunately, this is not the first time we have seen these so-called drive-by/waterhole attacks: once you have visited an affected website, embedded third-party malicious code is downloaded to your computer and subsequently infects it (if running Windows or Android as well as, less likely, Mac operating systems). Hence the name “drive-by”. As “20min.ch” is a very frequented website among CERN staff members and users, it makes it a perfect source for attacks against CERN (or other Geneva-based organisations): inste...

  6. PTAC driving safety survey results

    Energy Technology Data Exchange (ETDEWEB)

    Lloyd, E. [Petroleum Technology Alliance Canada, Calgary, AB (Canada)

    2005-07-01

    The results of a survey conducted by the Petroleum Technology Alliance Canada were presented. The survey identified ways in which companies in the oil and gas industry can reduce the potential for vehicle incidents, as well as improve fleet management techniques. Respondents provided a list of over 60 relevant technologies with high potential for application. Top driving safety challenges included adverse weather and road conditions, as well as driver attitude and awareness. Driver speed and fatigue were also seen as significant challenges, as well as encounters with wildlife and road conditions. Poor site conditions were also identified as a challenge, along with poor hazard recognition training, and lack of experience. A total of 157 representatives responded, whose fleets collectively drive approximately 136,500,000 km per year. The fleets totalled 15,800 vehicles. Respondents' affiliations with the oil and gas industry were included, as well as ownership classifications and company fleet sizes. Total annual fleet kilometers were presented, as well as the number of incidents per company per year, along with the number of respondents' animal strikes per year. tabs, figs.

  7. Ocean Acidification and Increased Temperature Have Both Positive and Negative Effects on Early Ontogenetic Traits of a Rocky Shore Keystone Predator Species.

    Science.gov (United States)

    Manríquez, Patricio H; Jara, María Elisa; Seguel, Mylene E; Torres, Rodrigo; Alarcon, Emilio; Lee, Matthew R

    2016-01-01

    The combined effect of ocean acidification and warming is expected to have significant effects on several traits of marine organisms. The gastropod Concholepas concholepas is a rocky shore keystone predator characteristic of the south-eastern Pacific coast of South America and an important natural resource exploited by small-scale artisanal fishermen along the coast of Chile and Peru. In this study, we used small juveniles of C. concholepas collected from the rocky intertidal habitats of southern Chile (39 °S) to evaluate under laboratory conditions the potential consequences of projected near-future levels of ocean acidification and warming for important early ontogenetic traits. The individuals were exposed long-term (5.8 months) to contrasting pCO2 (ca. 500 and 1400 μatm) and temperature (15 and 19 °C) levels. After this period we compared body growth traits, dislodgement resistance, predator-escape response, self-righting and metabolic rates. With respect to these traits there was no evidence of a synergistic interaction between pCO2 and temperature. Shell growth was negatively affected by high pCO2 levels only at 15 °C. High pCO2 levels also had a negative effect on the predator-escape response. Conversely, dislodgement resistance and self-righting were positively affected by high pCO2 levels at both temperatures. High tenacity and fast self-righting would reduce predation risk in nature and might compensate for the negative effects of high pCO2 levels on other important defensive traits such as shell size and escape behaviour. We conclude that climate change might produce in C. concholepas positive and negative effects in physiology and behaviour. In fact, some of the behavioural responses might be a consequence of physiological effects, such as changes in chemosensory capacity (e.g. predator-escape response) or secretion of adhesive mucous (e.g. dislodgement resistance). Moreover, we conclude that positive behavioural responses may assist in the

  8. Ocean Acidification and Increased Temperature Have Both Positive and Negative Effects on Early Ontogenetic Traits of a Rocky Shore Keystone Predator Species.

    Directory of Open Access Journals (Sweden)

    Patricio H Manríquez

    Full Text Available The combined effect of ocean acidification and warming is expected to have significant effects on several traits of marine organisms. The gastropod Concholepas concholepas is a rocky shore keystone predator characteristic of the south-eastern Pacific coast of South America and an important natural resource exploited by small-scale artisanal fishermen along the coast of Chile and Peru. In this study, we used small juveniles of C. concholepas collected from the rocky intertidal habitats of southern Chile (39 °S to evaluate under laboratory conditions the potential consequences of projected near-future levels of ocean acidification and warming for important early ontogenetic traits. The individuals were exposed long-term (5.8 months to contrasting pCO2 (ca. 500 and 1400 μatm and temperature (15 and 19 °C levels. After this period we compared body growth traits, dislodgement resistance, predator-escape response, self-righting and metabolic rates. With respect to these traits there was no evidence of a synergistic interaction between pCO2 and temperature. Shell growth was negatively affected by high pCO2 levels only at 15 °C. High pCO2 levels also had a negative effect on the predator-escape response. Conversely, dislodgement resistance and self-righting were positively affected by high pCO2 levels at both temperatures. High tenacity and fast self-righting would reduce predation risk in nature and might compensate for the negative effects of high pCO2 levels on other important defensive traits such as shell size and escape behaviour. We conclude that climate change might produce in C. concholepas positive and negative effects in physiology and behaviour. In fact, some of the behavioural responses might be a consequence of physiological effects, such as changes in chemosensory capacity (e.g. predator-escape response or secretion of adhesive mucous (e.g. dislodgement resistance. Moreover, we conclude that positive behavioural responses may assist

  9. Ocean Acidification and Increased Temperature Have Both Positive and Negative Effects on Early Ontogenetic Traits of a Rocky Shore Keystone Predator Species

    Science.gov (United States)

    Manríquez, Patricio H.; Jara, María Elisa; Seguel, Mylene E.; Torres, Rodrigo; Alarcon, Emilio; Lee, Matthew R.

    2016-01-01

    The combined effect of ocean acidification and warming is expected to have significant effects on several traits of marine organisms. The gastropod Concholepas concholepas is a rocky shore keystone predator characteristic of the south-eastern Pacific coast of South America and an important natural resource exploited by small-scale artisanal fishermen along the coast of Chile and Peru. In this study, we used small juveniles of C. concholepas collected from the rocky intertidal habitats of southern Chile (39°S) to evaluate under laboratory conditions the potential consequences of projected near-future levels of ocean acidification and warming for important early ontogenetic traits. The individuals were exposed long-term (5.8 months) to contrasting pCO2 (ca. 500 and 1400 μatm) and temperature (15 and 19°C) levels. After this period we compared body growth traits, dislodgement resistance, predator-escape response, self-righting and metabolic rates. With respect to these traits there was no evidence of a synergistic interaction between pCO2 and temperature. Shell growth was negatively affected by high pCO2 levels only at 15°C. High pCO2 levels also had a negative effect on the predator-escape response. Conversely, dislodgement resistance and self-righting were positively affected by high pCO2 levels at both temperatures. High tenacity and fast self-righting would reduce predation risk in nature and might compensate for the negative effects of high pCO2 levels on other important defensive traits such as shell size and escape behaviour. We conclude that climate change might produce in C. concholepas positive and negative effects in physiology and behaviour. In fact, some of the behavioural responses might be a consequence of physiological effects, such as changes in chemosensory capacity (e.g. predator-escape response) or secretion of adhesive mucous (e.g. dislodgement resistance). Moreover, we conclude that positive behavioural responses may assist in the adaptation

  10. 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

  11. Successful removable partial dentures.

    Science.gov (United States)

    Lynch, Christopher D

    2012-03-01

    Removable partial dentures (RPDs) remain a mainstay of prosthodontic care for partially dentate patients. Appropriately designed, they can restore masticatory efficiency, improve aesthetics and speech, and help secure overall oral health. However, challenges remain in providing such treatments, including maintaining adequate plaque control, achieving adequate retention, and facilitating patient tolerance. The aim of this paper is to review the successful provision of RPDs. Removable partial dentures are a successful form of treatment for replacing missing teeth, and can be successfully provided with appropriate design and fabrication concepts in mind.

  12. Ontogenetic differences of herbivory on woody and herbaceous plants: a meta-analysis demonstrating unique effects of herbivory on the young and the old, the slow and the fast.

    Science.gov (United States)

    Massad, Tara Joy

    2013-05-01

    The effect of herbivory on plant performance is the subject of a large number of ecological studies, and plant responses to herbivory range from reduced reproduction to overcompensation. Because plant defenses, stored resources, and allocation demands change throughout a plant's lifetime, it can be hypothesized the effects of herbivory also vary with development. The present work extends previous analyses to incorporate hundreds of studies in a new meta-analysis addressing this topic. Herbivores had an overall negative effect on plant growth and reproduction, and, in contrast to a previous meta-analysis, this work shows the timing of herbivory is relevant. Differences in the effects of herbivory between life stages existed for woody plant reproduction and perennial herb growth. In addition, tree and shrub growth was reduced by herbivore damage at early ontogenetic stages, and perennial herb reproduction was limited by adult stage herbivory. These results partially support the continuum of an ontogenetic response model. Finally, consideration of this synthesis in conjunction with other work led to the conclusion that different plant groups optimize their defense investments in unique ways. Slow-growing plants may strongly chemically defend young tissues, supporting the plant-age hypothesis, because early herbivory is detrimental to growth. Faster-growing herbs may invest more in antiherbivore defense when they are older, supporting the growth-differentiation balance hypothesis, because later herbivory limits their reproduction.

  13. A gate drive circuit for gate-turn-off (GTO) devices in series stack

    International Nuclear Information System (INIS)

    Despe, O.

    1999-01-01

    A gate-turn-off (GTO) switch is under development at the Advanced Photon Source as a replacement for a thyratron switch in high power pulsed application. The high voltage in the application requires multiple GTOs connected in series. One component that is critical to the success of GTO operation is the gate drive circuit. The gate drive circuit has to provide fast high-current pulses to the GTO gate for fast turn-on and turn-off. It also has to be able to operate while floating at high voltage. This paper describes a gate drive circuit that meets these requirements

  14. Soil invertebrate fauna enhances grassland succession and diversity

    NARCIS (Netherlands)

    Deyn, de G.B.; Raaijmakers, C.E.; Zoomer, H.R.; Berg, M.P.; Ruiter, de P.C.; Verhoef, H.A.; Bezemer, T.M.; Putten, van der W.H.

    2003-01-01

    One of the most important areas in ecology is to elucidate the factors that drive succession in ecosystems and thus influence the diversity of species in natural vegetation. Significant mechanisms in this process are known to be resource limitation(1-3) and the effects of aboveground vertebrate

  15. Leading Practice in Space Education: Successful Approaches by Specialist Schools

    Science.gov (United States)

    Schools Network, 2010

    2010-01-01

    The aim of the Government's Science, Technology, Engineering and Mathematics (STEM) programme is to ensure Britain's future success as a major centre for science, engineering and innovation. Specialist science, technology, engineering and maths & computing colleges help to drive this programme by becoming centres of excellence in STEM…

  16. Visualizing Student Flows: Busting Myths about Student Movement and Success

    Science.gov (United States)

    Heileman, Gregory L.; Babbitt, Terry H.; Abdallah, Chaouki T.

    2015-01-01

    Many institutions are trying to better understand the factors that drive student success and failure in order to improve the efficiency of degree production. Traditional academic reporting systems are not adequate for this purpose, since they are designed to measure outcomes, not to uncover the factors that influence them. To address this problem,…

  17. ACTS – SUCCESS STORY

    Indian Academy of Sciences (India)

    First page Back Continue Last page Overview Graphics. ACTS – SUCCESS STORY. Totally 103 experiments were conducted and the programme succeeded in the areas. Medicine; Education; Defence; Emergency Response; Maritime and Aeronautical Mobile Communications; Science and Astronomy.

  18. Goodbye Career, Hello Success.

    Science.gov (United States)

    Komisar, Randy

    2000-01-01

    Success in today's economy means throwing out the old career rules. The "noncareer" career is driven by passion for the work and has the fluidity and flexibility needed in the contemporary workplace. (JOW)

  19. Human Resource Outsourcing Success

    Directory of Open Access Journals (Sweden)

    Hasliza Abdul-Halim

    2014-07-01

    Full Text Available The existing literature on partnership seems to take the relationship between partnership quality and outsourcing success for granted. Therefore, this article aims at examining the role of service quality in strengthening the relationship between partnership quality and human resource (HR outsourcing success. The samples were obtained from 96 manufacturing organizations in Penang, Malaysia. The results showed that partnership quality variables such as trust, business understanding, and communication have significant positive impact on HR outsourcing success, whereas in general, service quality was found to partially moderate these relationships. Therefore, comprehending the HR outsourcing relationship in the context of service quality may assist the organizations to accomplish HR outsourcing success by identifying areas of expected benefits and improvements.

  20. Fertility Clinic Success Rates

    Science.gov (United States)

    ... Defects ART and Autism 2013 Assisted Reproductive Technology Fertility Clinic Success Rates Report Recommend on Facebook Tweet ... Additional Information About ART in the United States. Fertility Clinic Tables Introduction to Fertility Clinic Tables [PDF - ...

  1. Successful project management

    CERN Document Server

    Young, Trevor L

    2016-01-01

    Successful Project Management, 5th edition, is an essential guide for anyone who wants to improve the success rate of their projects. It will help managers to maintain a balance between the demands of the customer, the project, the team and the organization. Covering the more technical aspects of a project from start to completion it contains practised and tested techniques, covering project conception and start-up, how to manage stake holders, effective risk management, project planning and launch and execution. Also including a brand new glossary of key terms, it provides help with evaluating your project as well as practical checklists and templates to ensure success for any ambitious project manager. With over one million copies sold, the hugely popular Creating Success series covers a wide variety of topic, with the latest editions including new chapters such as Tough Conversations and Treating People Right. This indispensable business skills collection is suited to a variety of roles, from someone look...

  2. Definition of successful defibrillation

    NARCIS (Netherlands)

    Koster, Rudolph W.; Walker, Robert G.; van Alem, Anouk P.

    2006-01-01

    OBJECTIVES: The definition of defibrillation shock "success" endorsed by the International Liaison Committee on Resuscitation since the publication of Guidelines 2000 for Cardiopulmonary Resuscitation and Emergency Cardiac Care has been removal of ventricular fibrillation at 5 secs after shock

  3. Succession planning : phase II.

    Science.gov (United States)

    2008-06-01

    Succession planning is an organizational investment in the future. Institutional : knowledge is a critical ingredient in the culture of an organization, and its intangible : value becomes significant when an organization is faced with the need to pas...

  4. Do aggressive driving and negative emotional driving mediate the link between impulsiveness and risky driving among young Italian drivers?

    Science.gov (United States)

    Smorti, Martina; Guarnieri, Silvia

    2016-01-01

    The present study examined the contribution of impulsiveness and aggressive and negative emotional driving to the prediction of traffic violations and accidents taking into account potential mediation effects. Three hundred and four young drivers completed self-report measures assessing impulsiveness, aggressive and negative emotional driving, driving violations, and accidents. Structural equation modeling was used to assess the direct and indirect effects of impulsiveness on violations and accidents among young drivers through aggressive and negative emotional driving. Impulsiveness only indirectly influenced drivers' violations on the road via both the behavioral and emotional states of the driver. On the contrary, impulsiveness was neither directly nor indirectly associated with traffic accidents. Therefore, impulsiveness modulates young drivers' behavioral and emotional states while driving, which in turn influences risky driving.

  5. Hydraulic Rod Drives for the CAREM Reactor

    International Nuclear Information System (INIS)

    Mazzi, R.O

    2000-01-01

    CAREM belongs to those considered innovative reactors and their main design goal is obtain a significant improvement in safety.Requirements for the design of the first shutdown systems (FSS) is one of the mayor challenges from functional and reliability point of view, among most of the system of a nuclear reactor.Thus, the design of First Shutdown System must be in accordance with both, the system and the specific design criteria of the CAREM concept.In order to choose the best option for the control rod drive device, three different alternatives have been analysed in the frame of the Project.This paper discusses the advantages and disadvantages of each option and presents the main reasons to select the hydraulic type as the most promising one.The principles and main characteristics of the selected system are explained and the main goals to be obtained during development activities, in order to obtain a reliable design to successfully comply with operating requirements for reactor service are also presented

  6. Circuit for Driving Piezoelectric Transducers

    Science.gov (United States)

    Randall, David P.; Chapsky, Jacob

    2009-01-01

    The figure schematically depicts an oscillator circuit for driving a piezoelectric transducer to excite vibrations in a mechanical structure. The circuit was designed and built to satisfy application-specific requirements to drive a selected one of 16 such transducers at a regulated amplitude and frequency chosen to optimize the amount of work performed by the transducer and to compensate for both (1) temporal variations of the resonance frequency and damping time of each transducer and (2) initially unknown differences among the resonance frequencies and damping times of different transducers. In other words, the circuit is designed to adjust itself to optimize the performance of whichever transducer is selected at any given time. The basic design concept may be adaptable to other applications that involve the use of piezoelectric transducers in ultrasonic cleaners and other apparatuses in which high-frequency mechanical drives are utilized. This circuit includes three resistor-capacitor networks that, together with the selected piezoelectric transducer, constitute a band-pass filter having a peak response at a frequency of about 2 kHz, which is approximately the resonance frequency of the piezoelectric transducers. Gain for generating oscillations is provided by a power hybrid operational amplifier (U1). A junction field-effect transistor (Q1) in combination with a resistor (R4) is used as a voltage-variable resistor to control the magnitude of the oscillation. The voltage-variable resistor is part of a feedback control loop: Part of the output of the oscillator is rectified and filtered for use as a slow negative feedback to the gate of Q1 to keep the output amplitude constant. The response of this control loop is much slower than 2 kHz and, therefore, does not introduce significant distortion of the oscillator output, which is a fairly clean sine wave. The positive AC feedback needed to sustain oscillations is derived from sampling the current through the

  7. Research into Success

    Directory of Open Access Journals (Sweden)

    Bogomir Novak

    1997-12-01

    Full Text Available As competition is becoming ever more fierce, research into the prerequisites for success is gaining ground. By most people, success is perceived as an external phenomenon, but it is in fact the consequence of a person's readiness to perform in the world (of business. In the paper, Novak distinguishes between internal, external and group success. The essence of interna!success, which is the condition for the other two types of success, is assuming responsibility for, and exercising self-control over one's psychic phenomena. This in fact means that one needs to "reprogramme" the old patterns of behaviour and substitute them for the new, which leads to personality changes based on the understanding and acceptance of the self and others as they are. In realizing personal abilities, motives and goals, mental guiding laws must also be taken into account. Nowadays, the overall success of an organization is an important indicator of the quality of gro up work. The working patterns of individuals comply with the patterns used by his or her colleagues. When we do something for ourselves, we do it for others. In certain organizations, through accepted ways of communication all people become successful, and no body needs to be paid off. Employees wholly identify themselves with their organization, and vice versa. This three-part paradigm (I-Others-Community is the basis for various models of practical training for success, which are often idealized, but are primarily aimed at abolishing passivity and flaws in the system and its wider environment.

  8. Driving, brain injury and assistive technology.

    Science.gov (United States)

    Lane, Amy K; Benoit, Dana

    2011-01-01

    Individuals with brain injury often present with cognitive, physical and emotional impairments which impact their ability to resume independence in activities of daily living. Of those activities, the resumption of driving privileges is cited as one of the greatest concerns by survivors of brain injury. The integration of driving fundamentals within the hierarchical model proposed by Keskinen represents the complexity of skills and behaviors necessary for driving. This paper provides a brief review of specific considerations concerning the driver with TBI and highlights current vehicle technology which has been developed by the automotive industry and by manufacturers of adaptive driving equipment that may facilitate the driving task. Adaptive equipment technology allows for compensation of a variety of operational deficits, whereas technological advances within the automotive industry provide drivers with improved safety and information systems. However, research has not yet supported the use of such intelligent transportation systems or advanced driving systems for drivers with brain injury. Although technologies are intended to improve the safety of drivers within the general population, the potential of negative consequences for drivers with brain injury must be considered. Ultimately, a comprehensive driving evaluation and training by a driving rehabilitation specialist is recommended for individuals with brain injury. An understanding of the potential impact of TBI on driving-related skills and knowledge of current adaptive equipment and technology is imperative to determine whether return-to-driving is a realistic and achievable goal for the individual with TBI.

  9. Technology as a driving force

    Energy Technology Data Exchange (ETDEWEB)

    Torvund, T [Norsk Hydro A/S (Norway)

    1994-12-31

    The competitiveness of the Norwegian Continental shelf has been put firmly on the agenda in Norway since the report from a working group set up by the Ministry of Industry and Energy was released in February this year. If there is to be secured a long future for oil and gas activities, a reduction in the time and costs used in the projects of the order of 40-50%, without jeopardizing the high safety and environmental standards achieved in Norway. The paper addresses how technology can be a driving force in achieving these aims. But technology alone cannot do the job. Progress and changes in several other areas are also necessary, and the new scenario also calls for improved relations between all actors in the North Sea, authorities, oil companies, contractors and labour unions. 15 figs.

  10. Factors Driving Business Intelligence Culture

    Directory of Open Access Journals (Sweden)

    Rimvydas Skyrius

    2016-05-01

    Full Text Available The field of business intelligence (BI, despite rapid technology advances, continues to feature inadequate levels of adoption. The attention of researchers is shifting towards hu-man factors of BI adoption. The wide set of human factors influencing BI adoption con-tains elements of what we call BI culture – an overarching concept covering key managerial issues that come up in BI implementation. Research sources provide different sets of features pertaining to BI culture or related concepts – decision-making culture, analytical culture and others. The goal of this paper is to perform the review of research and practical sources to examine driving forces of BI – data-driven approaches, BI agility, maturity and acceptance – to point out culture-related issues that support BI adoption and to suggest an emerging set of factors influencing BI culture.

  11. Coordinated control of electrical drives

    International Nuclear Information System (INIS)

    Keresztely, S.

    1983-01-01

    The control system developed for the fuel handling machine of nuclear power plants contains seven microcomputers. Redundant hardware and software structure ensures high reliability and availability. The sensors are doubled and each set is connected to its own microcomputer for evaluation of measurements. The control program, coordinating seven electrical drives, is run on two identical microcomputers, and has access to both sets of measurement results. Two control desks are provided. The seventh microcomputer generates the digital picture of the working site around the actual position and the picture is sent to color TV monitors at the control desks. System reliability: failure of any part of the system causes an error message and no action. System availability: for emergency purposes, one of every pair of the identical subsystems must be operational. In this emergency mode unconditional reliability is lost. (author)

  12. Technology as a driving force

    International Nuclear Information System (INIS)

    Torvund, T.

    1994-01-01

    The competitiveness of the Norwegian Continental shelf has been put firmly on the agenda in Norway since the report from a working group set up by the Ministry of Industry and Energy was released in February this year. If there is to be secured a long future for oil and gas activities, a reduction in the time and costs used in the projects of the order of 40-50%, without jeopardizing the high safety and environmental standards achieved in Norway. The paper addresses how technology can be a driving force in achieving these aims. But technology alone cannot do the job. Progress and changes in several other areas are also necessary, and the new scenario also calls for improved relations between all actors in the North Sea, authorities, oil companies, contractors and labour unions. 15 figs

  13. Integration of motors and drives

    Energy Technology Data Exchange (ETDEWEB)

    Jackson, D.C. [Brook Hansen (United Kingdom)

    2000-07-01

    This paper examines the benefits of adopting a second-generation integrated motor and inverter. Removing the barriers to ensure that variable speed drives are more readily applied results in on-going cost savings to the user through energy savings plus process control benefits. In addition, the use of an integrated product instead of two separate components results in cost and time-savings to the installer. The simplification of integration, by transferring the guarantees of performance in efficiency, torque overload and stiffness, speed accuracy, noise and EMC compliance, allows optimisation by the design team to be realised by users and ease of application since the primary design team guarantees the product performance. The introduction of second generation compact product assists user conversion from present inefficient mechanical solutions. This technology is currently applicable in power ratings below 22 kW, which includes the vast majority of practical applications. (orig.)

  14. What Drives Politicians’ Online Popularity?

    DEFF Research Database (Denmark)

    Nielsen, Rasmus Kleis; Vaccari, Cristian

    2013-01-01

    The number of website visits, Facebook friends, or Twitter followers that politicians attract varies greatly, but little is known about what drives politicians' online popularity. In this article, we use data from a systematic tracking of congressional candidates' popularity on four web platforms...... in the 112 most competitive congressional districts in the 2010 U.S. midterm elections to address that question. Using multivariate regression models, we show that while district-level socioeconomic characteristics have little effect on candidates' online popularity, challengers and candidates in open......-seat races tend to attract larger audiences online, as do candidates who are more visible on political blogs. Surprisingly, how intensely candidates are covered in news media, how popular they are in opinion polls, and how much money they spend during the campaign show no significant effect. These findings...

  15. Subduction Drive of Plate Tectonics

    Science.gov (United States)

    Hamilton, W. B.

    2003-12-01

    Don Anderson emphasizes that plate tectonics is self-organizing and is driven by subduction, which rights the density inversion generated as oceanic lithosphere forms by cooling of asthenosphere from the top. The following synthesis owes much to many discussions with him. Hinge rollback is the key to kinematics, and, like the rest of actual plate behavior, is incompatible with bottom-up convection drive. Subduction hinges (which are under, not in front of, thin leading parts of arcs and overriding plates) roll back into subducting plates. The Pacific shrinks because bounding hinges roll back into it. Colliding arcs, increasing arc curvatures, back-arc spreading, and advance of small arcs into large plates also require rollback. Forearcs of overriding plates commonly bear basins which preclude shortening of thin plate fronts throughout periods recorded by basin strata (100 Ma for Cretaceous and Paleogene California). This requires subequal rates of advance and rollback, and control of both by subduction. Convergence rate is equal to rates of rollback and advance in many systems but is greater in others. Plate-related circulation probably is closed above 650 km. Despite the popularity of concepts of plumes from, and subduction into, lower mantle, there is no convincing evidence for, and much evidence against, penetration of the 650 in either direction. That barrier not only has a crossing-inhibiting negative Clapeyron slope but also is a compositional boundary between fractionated (not "primitive"), sluggish lower mantle and fertile, mobile upper mantle. Slabs sink more steeply than they dip. Slabs older than about 60 Ma when their subduction began sink to, and lie down on and depress, the 650-km discontinuity, and are overpassed, whereas younger slabs become neutrally buoyant in mid-upper mantle, into which they are mixed as they too are overpassed. Broadside-sinking old slabs push all upper mantle, from base of oceanic lithosphere down to the 650, back under

  16. Drivers’ Age, Gender, Driving Experience, and Aggressiveness as Predictors of Aggressive Driving Behaviour

    Directory of Open Access Journals (Sweden)

    Perepjolkina Viktorija

    2011-12-01

    Full Text Available Recent years have seen a growing interest in the problem of aggressive driving. In the presentstudy two demographic variables (gender and age, two non-psychological driving-experiencerelated variables (annual mileage and legal driving experience in years and aggressiveness asa personality trait (including behavioural and affective components as psychological variableof individual differences were examined as potential predictors of aggressive driving. The aimof the study was to find out the best predictors of aggressive driving behaviour. The study wasbased on an online survey, and 228 vehicle drivers in Latvia participated in it. The questionnaireincluded eight-item Aggressive Driving Scale (Bone & Mowen, 2006, short Latvian versionof the Buss-Perry Aggression Questionnaire (AQ; Buss & Perry, 1992, and questions gainingdemographic and driving experience information. Gender, age and annual mileage predictedaggressive driving: being male, young and with higher annual driving exposure were associatedwith higher scores on aggressive driving. Dispositional aggressiveness due to anger componentwas a significant predictor of aggressive diving score. Physical aggression and hostility wereunrelated to aggressive driving. Altogether, the predictors explained a total of 28% of thevariance in aggressive driving behaviour. Findings show that dispositional aggressiveness,especially the anger component, as well as male gender, young age and higher annual mileagehas a predictive validity in relation to aggressive driving. There is a need to extend the scope ofpotential dispositional predictors pertinent to driving aggression.

  17. Driving safety after brain damage: follow-up of twenty-two patients with matched controls.

    Science.gov (United States)

    Katz, R T; Golden, R S; Butter, J; Tepper, D; Rothke, S; Holmes, J; Sahgal, V

    1990-02-01

    Driving after brain damage is a vital issue, considering the large number of patients who suffer from cerebrovascular and traumatic encephalopathy. The ability to operate a motor vehicle is an integral part of independence for most adults and so should be preserved whenever possible. The physician may estimate a patient's ability to drive safely based on his own examination, the evaluation of a neuropsychologist, and a comprehensive driving evaluation--testing, driving simulation, behind-the-wheel observation--with a driving specialist. This study sought to evaluate the ability of brain-damaged individuals to operate a motor vehicle safely at follow-up. These patients had been evaluated (by a physician, a neuropsychologist, and a driving specialist) and were judged able to operate a motor vehicle safely after their cognitive insult. Twenty-two brain-damaged patients who were evaluated at our institution were successfully followed up to five years (mean interval of 2.67 years). Patients were interviewed by telephone. Their driving safely was compared with a control group consisting of a close friend or spouse of each patient. Statistical analysis revealed no difference between patient and control groups in the type of driving, the incidence of speeding tickets, near accidents, and accidents, and the cost of vehicle damage when accidents occurred. The patient group was further divided into those who had, and those who had not experienced driving difficulties so that initial neuropsychologic testing could be compared. No significant differences were noted in any aspect of the neuropsychologic test battery. We conclude that selected brain-damaged patients who have passed a comprehensive driving assessment as outlined were as fit to drive as were their normal matched controls.(ABSTRACT TRUNCATED AT 250 WORDS)

  18. Designing feedback to mitigate teen distracted driving: A social norms approach.

    Science.gov (United States)

    Merrikhpour, Maryam; Donmez, Birsen

    2017-07-01

    The purpose of this research is to investigate teens' perceived social norms and whether providing normative information can reduce distracted driving behaviors among them. Parents are among the most important social referents for teens; they have significant influences on teens' driving behaviors, including distracted driving which significantly contributes to teens' crash risks. Social norms interventions have been successfully applied in various domains including driving; however, this approach is yet to be explored for mitigating driver distraction among teens. Forty teens completed a driving simulator experiment while performing a self-paced visual-manual secondary task in four between-subject conditions: a) social norms feedback that provided a report at the end of each drive on teens' distracted driving behavior, comparing their distraction engagement to their parent's, b) post-drive feedback that provided just the report on teens' distracted driving behavior without information on their parents, c) real-time feedback in the form of auditory warnings based on eyes of road-time, and d) no feedback as control. Questionnaires were administered to collect data on these teens' and their parents' self-reported engagement in driver distractions and the associated social norms. Social norms and real-time feedback conditions resulted in significantly smaller average off-road glance duration, rate of long (>2s) off-road glances, and standard deviation of lane position compared to no feedback. Further, social norms feedback decreased brake response time and percentage of time not looking at the road compared to no feedback. No major effect was observed for post-drive feedback. Questionnaire results suggest that teens appeared to overestimate parental norms, but no effect of feedback was found on their perceptions. Feedback systems that leverage social norms can help mitigate driver distraction among teens. Overall, both social norms and real-time feedback induced

  19. Multi-Motor Drives for Crane Application

    Directory of Open Access Journals (Sweden)

    MITROVIC, N.

    2009-10-01

    Full Text Available This paper focuses on the application of adjustable speed induction motor drives for gantry cranes. Modern solution considers application of frequency converters for all drives. Multi-motor drives are standard solutions in crane application and requirements of load sharing are present. Presented algorithm provides load sharing proportional to the rated motor power on the simple and practically applicable method on the basis of estimated torques by frequency converters, and controller realized in PLC. Special attention is devoted to wide span gantry drive and algorithm for skew elimination. Solutions for load distribution in multi-motor drive, as well as mode of gantry drive skew elimination, are described. Suggested solution concept is confirmed by the experimental results.

  20. What drives Users' Website Registration?

    NARCIS (Netherlands)

    T. Li (Ting); P.A. Pavlou (Paul)

    2013-01-01

    textabstractUser registration is an important prerequisite for the success of many websites by enabling users to gain access to domain information and personalized content. It is not always desirable for users, however, because they need to disclose personal information. This paper examines what

  1. Multidisciplinary Efforts Driving Translational Theranostics

    Science.gov (United States)

    Hu, Tony Y.

    2014-01-01

    This themed issue summarizes significant efforts aimed at using “biological language” to discern between “friends” and “foes” in the context of theranostics for true clinical application. It is expected that the success of theranostics depends on multidisciplinary efforts, combined to expedite our understanding of host responses to “customized” theranostic agents and formulating individualized therapies. PMID:25285169

  2. Adolescence, Attention Allocation, and Driving Safety

    OpenAIRE

    Romer, Daniel; Lee, Yi-Ching; McDonald, Catherine C.; Winston, Flaura K.

    2014-01-01

    Motor vehicle crashes are the leading source of morbidity and mortality in adolescents in the United States and the developed world. Inadequate allocation of attention to the driving task and to driving hazards are important sources of adolescent crashes. We review major explanations for these attention failures with particular focus on the roles that brain immaturity and lack of driving experience play in causing attention problems. The review suggests that the potential for overcoming inexp...

  3. Successful ageing for psychiatrists.

    Science.gov (United States)

    Peisah, Carmelle

    2016-04-01

    This paper aims to explore the concept and determinants of successful ageing as they apply to psychiatrists as a group, and as they can be applied specifically to individuals. Successful ageing is a heterogeneous, inclusive concept that is subjectively defined. No longer constrained by the notion of "super-ageing", successful ageing can still be achieved in the face of physical and/or mental illness. Accordingly, it remains within the reach of most of us. It can, and should be, person-specific and individually defined, specific to one's bio-psycho-social and occupational circumstances, and importantly, reserves. Successful professional ageing is predicated upon insight into signature strengths, with selection of realistic goal setting and substitution of new goals, given the dynamic nature of these constructs as we age. Other essential elements are generativity and self-care. Given that insight is key, taking a regular stock or inventory of our reserves across bio-psycho-social domains might be helpful. Importantly, for successful ageing, this needs to be suitably matched to the professional task and load. This lends itself to a renewable personal ageing plan, which should be systemically adopted with routine expectations of self-care and professional responsibility. © The Royal Australian and New Zealand College of Psychiatrists 2015.

  4. Heating and current drive on NSTX

    Science.gov (United States)

    Wilson, J. R.; Batchelor, D.; Carter, M.; Hosea, J.; Ignat, D.; LeBlanc, B.; Majeski, R.; Ono, M.; Phillips, C. K.; Rogers, J. H.; Schilling, G.

    1997-04-01

    Low aspect ratio tokamaks pose interesting new challenges for heating and current drive. The NSTX (National Spherical Tokamak Experiment) device to be built at Princeton is a low aspect ratio toroidal device that has the achievement of high toroidal beta (˜45%) and non-inductive operation as two of its main research goals. To achieve these goals significant auxiliary heating and current drive systems are required. Present plans include ECH (Electron cyclotron heating) for pre-ionization and start-up assist, HHFW (high harmonic fast wave) for heating and current drive and eventually NBI (neutral beam injection) for heating, current drive and plasma rotation.

  5. Heating and current drive on NSTX

    International Nuclear Information System (INIS)

    Wilson, J.R.; Batchelor, D.; Carter, M.; Hosea, J.; Ignat, D.; LeBlanc, B.; Majeski, R.; Ono, M.; Phillips, C.K.; Rogers, J.H.; Schilling, G.

    1997-01-01

    Low aspect ratio tokamaks pose interesting new challenges for heating and current drive. The NSTX (National Spherical Tokamak Experiment) device to be built at Princeton is a low aspect ratio toroidal device that has the achievement of high toroidal beta (∼45%) and non-inductive operation as two of its main research goals. To achieve these goals significant auxiliary heating and current drive systems are required. Present plans include ECH (Electron cyclotron heating) for pre-ionization and start-up assist, HHFW (high harmonic fast wave) for heating and current drive and eventually NBI (neutral beam injection) for heating, current drive and plasma rotation. copyright 1997 American Institute of Physics

  6. Configuring NIF for direct drive experiments

    International Nuclear Information System (INIS)

    Eimerl, D.; Rothenberg, J.; Key, M.

    1995-01-01

    The National Ignition Facility (NIF) is a proposed 1.8 MJ laser facility for carrying out experiments in inertial confinement fusion, currently designed for indirect drive experiments. The direct drive approach is being pursued at the 30 kJ Omega facility at the University of Rochester. In this paper we discuss the modifications to the NIF laser that would be required for both indirect and direct drive experiments. A primary concern is the additional cost of adding direct drive capability to the facility

  7. Comparison of Unsafe Driving Across Medical Conditions.

    Science.gov (United States)

    Moon, Sanghee; Ranchet, Maud; Tant, Mark; Akinwuntan, Abiodun E; Devos, Hannes

    2017-09-01

    To compare risks of unsafe driving in patients with medical conditions. This large population-based study included all patients who were referred for a fitness-to-drive evaluation at an official driving evaluation center in 2013 and 2014. Risks of unsafe driving included physician's fitness-to-drive recommendation, comprehensive fitness-to-drive decision, motor vehicle crash history, and traffic violation history. A total of 6584 patients were included in the study. Risks of unsafe driving were significantly different across medical conditions (Pdriving. Patients with psychiatric conditions or substance abuse did worse on most driving safety outcomes, despite their low representation in the total sample (359 [6%] and 46 [1%], respectively). The risk of unsafe driving varied greatly across medical conditions. Sensitization campaigns, education, and medical guidelines for physicians and driver licensing authorities are warranted to identify patients at risk, especially for those with psychiatric conditions and substance abuse problems. Copyright © 2017 Mayo Foundation for Medical Education and Research. Published by Elsevier Inc. All rights reserved.

  8. Simulation and Analysis of Chain Drive Systems

    DEFF Research Database (Denmark)

    Pedersen, Sine Leergaard

    mathematical models, and compare to the prior done research. Even though the model is developed at first for the use of analysing chain drive systems in marine engines, the methods can with small changes be used in general, as for e.g. chain drives in industrial machines, car engines and motorbikes. A novel...... with a real tooth profile proves superior to other applied models. With this model it is possible to perform a dynamic simulation of large marine engine chain drives. Through the application of this method, it is shown that the interrelated dynamics of the elements in the chain drive system is captured...

  9. Driving Under the Influence (of Language).

    Science.gov (United States)

    Barrett, Daniel Paul; Bronikowski, Scott Alan; Yu, Haonan; Siskind, Jeffrey Mark

    2017-06-09

    We present a unified framework which supports grounding natural-language semantics in robotic driving. This framework supports acquisition (learning grounded meanings of nouns and prepositions from human sentential annotation of robotic driving paths), generation (using such acquired meanings to generate sentential description of new robotic driving paths), and comprehension (using such acquired meanings to support automated driving to accomplish navigational goals specified in natural language). We evaluate the performance of these three tasks by having independent human judges rate the semantic fidelity of the sentences associated with paths. Overall, machine performance is 74.9%, while the performance of human annotators is 83.8%.

  10. Risky driving and lifestyles in adolescence.

    Science.gov (United States)

    Bina, Manuela; Graziano, Federica; Bonino, Silvia

    2006-05-01

    Several studies have shown that risky driving is especially prevalent among young drivers and recent research has pointed out that driving in adolescence should be investigated in the more general context of adolescent development. The first aim of this contribution was to analyze involvement in risky driving in a normative sample of 645 Italian adolescents, boys and girls, aged 14-17, through a self-report questionnaire. A second aim was to evaluate the association between risky driving and lifestyle, defined as involvement in other health risk behaviors and leisure activities. The main results showed that many adolescents drove cars and motorcycles without the required driving license and the most frequent offences were speeding and failure to maintain a safe braking distance. Gender and age differences were also investigated. Results concerning the association between risky driving and lifestyle showed that risky driving was not an isolated behavior. Boys who displayed risky driving practices were more likely to adopt a lifestyle characterized by high involvement in antisocial behaviors, tobacco smoking, comfort eating and time spent in non-organized activities with friends. Girls involved in risky driving were more likely to be involved in other risk-taking behaviors, antisocial behaviors and drug use.

  11. Risky driving behaviors in Tehran, Iran.

    Science.gov (United States)

    Shams, Mohsen; Rahimi-Movaghar, Vafa

    2009-03-01

    Iran has one of the highest fatality rates due to road traffic crashes (RTC) in the world. The disability adjusted life years (DALYs) for RTC in Iran is more than 1,300,000 years, which is more than that for any other disease such as cardiovascular or cancer. We evaluated risky driving behaviors in Tehran, the capital of Iran. A retrospective analysis was conducted based on the data obtained from the Tehran Police Safety Driving Department. Offenses and crashes were studied in different municipal districts in Tehran from March 2006 to March 2007. The inclusion criteria were risky driving behaviors fined by the police. Nonbehavioral offences were excluded. There were 3,821,798 offenses in Tehran. Not wearing a seat belt was the most common (59%) example of risky driving behavior, followed by tailgating, not wearing motorcycle helmets, talking on the cell phone while driving, overtaking from the wrong side, speeding, not driving between the lanes, weaving in and out of traffic, left deviation, and changing lanes without signals. The most common causes of RTC in Tehran are speeding, overtaking from the wrong side, and the rapid changing of driving lanes. The study factors effective in preventing risky driving behaviors in Tehran is recommended. The consideration of specific characteristics of the municipal districts is necessary to reduce risky driving behaviors.

  12. Review of current drive theory: selected topics

    International Nuclear Information System (INIS)

    Fisch, N.J.

    1993-01-01

    Two themes in current drive theory in tokamaks are reviewed, both relevant to the progression of tokamak experiments toward the reactor regime. First, the physics of the tail electrons is reviewed. These electrons are capable of carrying enormous rf-driven electric current, and, in the course of current-drive experiments worldwide not only has the current drive effect been demonstrated, but the underlying physical description of these tail electrons has been established. Second, anticipating the presence of the energetic alpha particles that result from D-T reactions in a reactor, certain mechanisms through which these alpha particles can be used to facilitate current-drive are reviewed. (Author)

  13. Bangladesh becomes "success story".

    Science.gov (United States)

    1999-01-01

    The State Minister for Health and Family of Bangladesh, Dr. Mohammed Amanullah, highlighted some of the successes being achieved by his country in lowering fertility and improving the lives of the people since the 1994 International Conference on Population and Development. Some of these successes include practical measures to eliminate violence against women; introduction of a quota for women in public sector employment; and launching of the Health and Population Sector Program to provide a one-stop, full range of essential reproductive health, family planning and child health services through an integrated delivery mechanism. Moreover, the Minister informed the Forum participants that their success is attributable to many factors which include support from the government, from non-governmental organizations, civil society, mass media, religious and other community leaders, intersectoral collaboration, microcredit and income-generation activities.

  14. Proactive vs. reactive car driving: EEG evidence for different driving strategies of older drivers

    Science.gov (United States)

    Wascher, Edmund; Getzmann, Stephan

    2018-01-01

    Aging is associated with a large heterogeneity in the extent of age-related changes in sensory, motor, and cognitive functions. All these functions can influence the performance in complex tasks like car driving. The present study aims to identify potential differences in underlying cognitive processes that may explain inter-individual variability in driving performance. Younger and older participants performed a one-hour monotonous driving task in a driving simulator under varying crosswind conditions, while behavioral and electrophysiological data were recorded. Overall, younger and older drivers showed comparable driving performance (lane keeping). However, there was a large difference in driving lane variability within the older group. Dividing the older group in two subgroups with low vs. high driving lane variability revealed differences between the two groups in electrophysiological correlates of mental workload, consumption of mental resources, and activation and sustaining of attention: Older drivers with high driving lane variability showed higher frontal Alpha and Theta activity than older drivers with low driving lane variability and—with increasing crosswind—a more pronounced decrease in Beta activity. These results suggest differences in driving strategies of older and younger drivers, with the older drivers using either a rather proactive and alert driving strategy (indicated by low driving lane variability and lower Alpha and Beta activity), or a rather reactive strategy (indicated by high driving lane variability and higher Alpha activity). PMID:29352314

  15. Personality correlates of self-employed small business owners' success.

    Science.gov (United States)

    Owens, Kimberly S; Kirwan, Jeral R; Lounsbury, John W; Levy, Jacob J; Gibson, Lucy W

    2013-01-01

    Drawing on prior occupational choice research on entrepreneurs and self-employed business owners, we examined personality predictors of their occupational business success and work satisfaction. PARTICIPANTS AND PROCEDURES: A sample of 147 small business owners completed a web-based assessment of 14 work-related personality traits--adaptability, autonomy, competitiveness, dependability, emotional resilience, goal-setting, optimism, persistence, risk tolerance, self-promotion, networking, and tolerance for financial insecurity, work-based locus of control, and work drive--and three self-reported indices of business success--revenue growth, profit growth, and income growth--as well as multiple facets of individual satisfaction. Criterion variables included composite business success and overall satisfaction. Ten traits correlated with business success. The top four personality predictors of success--goal-setting, social networking, emotional resilience, and work drive--together accounted for 16% of the variance. Similarly, 12 of 14 personality traits were positively related to overall satisfaction. The top three personality predictors of satisfaction--optimism, work-based locus of control, and work drive--accounted for 29% of the variability in satisfaction. An expectancy analysis revealed that the percent of participants who reported at least a 20% increase in sales and profits the preceding year was 26% versus 54% for individual scoring in the lower and upper third of a personality composite measure. Results carry implications for future research, and have direct, practical applications for prospective and current entrepreneurs and self-employed owners of small businesses.

  16. Comparison of electric drives for road vehicles

    Energy Technology Data Exchange (ETDEWEB)

    Bader, C; Stephan, W [Deutsche Automobilgesellschaft m.b.H., Esslingen (Germany, F.R.)

    1977-01-01

    The low energy-storage capacity of the electrolytic energy-storage apparatus available at the moment limits the practical use of electric vehicles to meeting the requirements for restricted areas. But in this field of application, conversion from drive with internal combustion engine to electric drive can be considered only if a reduction of costs is achieved with electric drive. From the wide range of possible drive units the most suitable is found to be the dc squirrelcage motor the speed of which is controlled by field weakening. In the case of a motor with conventional design, the controllable drive range is limited to about 1 : 3, so that generally additional measures are required for extending the drive range. But if the motor is fitted with a compensation winding, field weakening to give a controlled speed range of 1 : 8 can be obtained. To evaluate the different drive units under consideration use is made of the acceleration when, according to the drive system, advantages are obtained from the point of view of energy consumption with disadvantages in acceleration time, and vice versa. By using vehicles proven in practice with different drive systems, either with hydrodynamic transducer and battery switchover, or else with changeover gear and mechanical clutch, the overall construction of the different control and protective arrangements are demonstrated. It is then found that the extra cost of regulation in the case of automatic drive operation is partly compensated by the additional protective devices which are required to limit the effects of any incorrect operations with a manually-operated drive.

  17. Teens' distracted driving behavior: Prevalence and predictors.

    Science.gov (United States)

    Gershon, Pnina; Zhu, Chunming; Klauer, Sheila G; Dingus, Tom; Simons-Morton, Bruce

    2017-12-01

    Teen drivers' over-involvement in crashes has been attributed to a variety of factors, including distracted driving. With the rapid development of in-vehicle systems and portable electronic devices, the burden associated with distracted driving is expected to increase. The current study identifies predictors of secondary task engagement among teenage drivers and provides basis for interventions to reduce distracted driving behavior. We described the prevalence of secondary tasks by type and driving conditions and evaluated the associations between the prevalence of secondary task engagement, driving conditions, and selected psychosocial factors. The private vehicles of 83 newly-licensed teenage drivers were equipped with Data Acquisition Systems (DAS), which documented driving performance measures, including secondary task engagement and driving environment characteristics. Surveys administered at licensure provided psychosocial measures. Overall, teens engaged in a potentially distracting secondary task in 58% of sampled road clips. The most prevalent types of secondary tasks were interaction with a passenger, talking/singing (no passenger), external distraction, and texting/dialing the cell phone. Secondary task engagement was more prevalent among those with primary vehicle access and when driving alone. Social norms, friends' risky driving behaviors, and parental limitations were significantly associated with secondary task prevalence. In contrast, environmental attributes, including lighting and road surface conditions, were not associated with teens' engagement in secondary tasks. Our findings indicated that teens engaged in secondary tasks frequently and poorly regulate their driving behavior relative to environmental conditions. Practical applications: Peer and parent influences on secondary task engagement provide valuable objectives for countermeasures to reduce distracted driving among teenage drivers. Copyright © 2017 National Safety Council and

  18. Driving automation forward : human factors for limited-ability autonomous driving systems.

    Science.gov (United States)

    2010-01-01

    Over the past 100 years, there has been a : steady progression of innovations that : enhance the driving experience, in particular : the continuing trend toward automating more : driving tasks. Human Factors for Limited-Ability : Autonomous Drivin...

  19. Driving a mechanical resonator into coherent states via random measurements

    International Nuclear Information System (INIS)

    Garcia, Ll; Wu, L-A; Chhajlany, R W; Li, Y

    2013-01-01

    We propose dynamical schemes to engineer coherent states of a mechanical resonator (MR) coupled to an ancillary, superconducting flux qubit. The flux qubit, when repeatedly projected on to its ground state, drives the MR into a coherent state in probabilistic, albeit heralded fashion. Assuming no operations on the state of the MR during the protocol, coherent states are successfully generated only up to a certain value of the displacement parameter. This restriction can be overcome at the cost of a one-time operation on the initial state of the MR. We discuss the possibility of experimental realization of the presented schemes. (paper)

  20. Control rod drive mechanism stator loss of coolant test

    International Nuclear Information System (INIS)

    Besel, L.; Ibatuan, R.

    1977-04-01

    This report documents the stator loss of coolant test conducted at HEDL on the lead unit Control Rod Drive Mechanism (CRDM) in February, 1977. The purpose of the test was to demonstrate scram capability of the CRDM with an uncooled stator and to obtain a time versus temperature curve of an uncooled stator under power. Brief descriptions of the test, hardware used, and results obtained are presented in the report. The test demonstrated that the CRDM could be successfully scrammed with no anomalies in both the two-phase and three-phase stator winding hold conditions after the respective equilibrium stator temperatures had been obtained with no stator coolant

  1. SUPERCOLLIDER: String test success

    International Nuclear Information System (INIS)

    Anon.

    1992-01-01

    On 14 August at the Superconducting Supercollider (SSC) Laboratory in Ellis County, Texas, the Accelerator Systems String Test (ASST) successfully met its objective by operating a half-cell of five collider dipole magnets, one quadrupole magnet, and two spool pieces at the design current of 6500 amperes

  2. Mindfulness and Student Success

    Science.gov (United States)

    Leland, Matt

    2015-01-01

    Mindfulness has long been practiced in Eastern spiritual traditions for personal improvement, and educators and educational institutions have recently begun to explore its usefulness in schools. Mindfulness training can be valuable for helping students be more successful learners and more connected members of an educational community. To determine…

  3. International Student Success

    Science.gov (United States)

    Smith, Clayton

    2016-01-01

    This article, with a focus on North American postsecondary education, identifies international students as a strategic enrollment management institutional priority; presents themes in the international student retention, satisfaction, and success research literature; and describes related best practices. It also presents the findings from an…

  4. America's Success Syndrome

    Science.gov (United States)

    Duplisea, Eric A.

    1974-01-01

    America's earliest schools taught career awareness and job skills, but for 200 years it was a speciality curriculum--cultivating a classical heritage predominated. Recently the hard sell message is that schooling and credentialism ensure entry into the "successful life". Vocational educators must become leaders, explode this myth, and redefine…

  5. Focus on Success

    Science.gov (United States)

    Frey, Susan

    2011-01-01

    Successful middle schools do not happen by accident--they happen through leadership. Principals promote a shared vision that empowers school staffs to set high standards and continuously improve student achievement. And these middle grade educators also try to help their adolescent students see the connection between their work in school and their…

  6. Successful international negotiations

    International Nuclear Information System (INIS)

    Gerry, G.

    1997-01-01

    These remarks on successful international trade negotiations deal with the following topics: culture and differences in psychology; building friendly relationships and letting both sides appear to win; well written proposals; security of negotiating information; the complexity and length of nuclear negotiations

  7. Success in Entrepreneurship

    DEFF Research Database (Denmark)

    Iversen, Jens; Malchow-Møller, Nikolaj; Sørensen, Anders

    2016-01-01

    What makes a successful entrepreneur? Using Danish register data, we find strong support for the hypothesis that theoretical skills from schooling and practical skills acquired through wage-work are complementary inputs in the human capital earnings function of entrepreneurs. In fact, we find tha...

  8. Successfully Adapting to Change.

    Science.gov (United States)

    Baird, James R.

    1989-01-01

    Describes methods used to successfully adapt to reductions in budget allocations in the University of Utah's Instructional Media Services Department. Three main areas of concern are addressed: morale and staff development; adapting to change in the areas of funding, control, media priorities, and technology; and planning for the future. (LRW)

  9. Beyond Success and Failure

    NARCIS (Netherlands)

    Etalle, Sandro; Jaffar, Joxan; van Raamsdonk, Femke

    We study a new programming framework based on logic programming where success and failure are replaced by predicates for adequacy and inadequacy. Adequacy allows to extract a result from a partial computation, and inadequacy allows to flexibly constrain the search space. In this parameterized

  10. Predicting Commissary Store Success

    Science.gov (United States)

    2014-12-01

    stores or if it is possible to predict that success. Multiple studies of private commercial grocery consumer preferences , habits and demographics have...appropriate number of competitors due to the nature of international cultures and consumer preferences . 2. Missing Data Four of the remaining stores

  11. Characteristics of Successful Entrepreneurs.

    Science.gov (United States)

    McClelland, David C.

    1987-01-01

    Comparison of characteristics of 12 average and 12 superior small business people in three developing nations (India, Malawi, and Ecuador) found proactive qualities such as initiative and assertiveness, achievement orientation, and commitment to others characteristic of successful entrepreneurs. Other expected qualities (self-confidence,…

  12. Measuring strategic success.

    Science.gov (United States)

    Gish, Ryan

    2002-08-01

    Strategic triggers and metrics help healthcare providers achieve financial success. Metrics help assess progress toward long-term goals. Triggers signal market changes requiring a change in strategy. All metrics may not move in concert. Organizations need to identify indicators, monitor performance.

  13. Passport to Success

    Science.gov (United States)

    Tomlinson, Nigel

    2002-01-01

    Looks at the "Passport to Success" scheme introduced by the Sheffield Chamber of Commerce in a bid to address the employability skills problem among young people. States that the scheme was launched in September 2001 in partnership with a local comprehensive school with the intention of helping pupils make the transition from school into…

  14. Leading to Success

    Science.gov (United States)

    Koballa, Thomas R., Jr.; Bradbury, Leslie U.

    2009-01-01

    Teacher mentoring has its unique challenges that are often associated with the teachers' content specialties. For this reason, the involvement and support of school leaders is essential to teachers' mentoring success. Regardless of content specialty, all teachers face challenges that should be considered when organizing and implementing mentoring.…

  15. Successful introduction of innovations

    International Nuclear Information System (INIS)

    Schoots, K.; Jeeninga, H.

    2008-01-01

    The introduction of new technology is sometimes troubled by discontinuity in incentive schemes. By making prior assessments of the necessary means, the real time span for the incentive scheme and by maintaining this scheme until the technology is mature enough to enter the market, the success of innovation trajectories can be increased significantly. [mk] [nl

  16. Successful introduction of innovation

    International Nuclear Information System (INIS)

    Schoots, K.; Jeeninga, H.

    2008-01-01

    The introduction of new technology sometimes proceeds sluggishly due to discontinuity in incentive schemes. Estimating in advance which means are required, what a realistic time span is for the incentive scheme and continuing this scheme until the technology is marketable can significantly increase the success of innovation trajectories. [mk] [nl

  17. Successfully combating prejudice

    Indian Academy of Sciences (India)

    Lawrence

    Sir Jagdish Chandra Bose, and fascinated by his work that showed that plants were ... U.S., in 1972, I was invited to take up a faculty position at the newly established ... success because of their different social commitments. Today when I look ...

  18. Designing for success

    Energy Technology Data Exchange (ETDEWEB)

    Altounyan, P.; Hurt, K.; Bigby, D. [Rock Mechanics Technology, Stanhope Bretby (United Kingdom)

    1999-07-01

    Successful underground coal mining is dependent on a number of key factors, particularly geotechnical suitability. The impact of rock mechanics on underground mine design and mining methods is discussed in this article. Methods on minimising stress effects in room and pillar mining, and longwall mining are outlined. The use of computer numerical modelling in mine design is mentioned. 8 figs.

  19. Effect of salinity on the metabolism and osmoregulation of selected ontogenetic stages of an amazon population of Macrobrachium amazonicum shrimp (Decapoda, Palaemonidae

    Directory of Open Access Journals (Sweden)

    CCM. Mazzarelli

    acids gets diminished and oxygen consumption elevated, probably due to greater energy expenditure with the active transportation of salts through epithelial membranes. Osmotic challenges also seem to alter throughout development, given that in zoeae II oxygen consumption is elevated on brackish water of 18, but in zoeae V it happens in fresh water. After M. amazonicum metamorphosis, free amino acids begin to play an important role as intracellular osmolytes, because we verified an increase of up to 40% in post-larvae exposed to brackish water of 18. The main free amino acids involved in cell volume regulation of ontogenetic stages evaluated were the non essential ones: glutamic acid, glycine, alanine, arginine, and proline. Interestingly, larvae from estuarine population studied here survived until the zoeae V stage in fresh water, but in some populations far from the sea, zoeae die right after eclosion in fresh water or they do not reach zoeae III stage. In addition, given that in favorable conditions caridean shrimp larvae shorten their development, we may infer that the cultivation environment, in which larvae developed in the present work, was appropriate, because almost all zoeae VIII kept on brackish water underwent metamorphosis directly to post-larvae and did not go through zoeae IX stage.

  20. Effect of salinity on the metabolism and osmoregulation of selected ontogenetic stages of an Amazon population of Macrobrachium amazonicum shrimp (Decapoda, Palaemonidae).

    Science.gov (United States)

    Mazzarelli, C C M; Santos, M R; Amorim, R V; Augusto, A

    2015-05-01

    diminished and oxygen consumption elevated, probably due to greater energy expenditure with the active transportation of salts through epithelial membranes. Osmotic challenges also seem to alter throughout development, given that in zoeae II oxygen consumption is elevated on brackish water of 18, but in zoeae V it happens in fresh water. After M. amazonicum metamorphosis, free amino acids begin to play an important role as intracellular osmolytes, because we verified an increase of up to 40% in post-larvae exposed to brackish water of 18. The main free amino acids involved in cell volume regulation of ontogenetic stages evaluated were the non essential ones: glutamic acid, glycine, alanine, arginine, and proline. Interestingly, larvae from estuarine population studied here survived until the zoeae V stage in fresh water, but in some populations far from the sea, zoeae die right after eclosion in fresh water or they do not reach zoeae III stage. In addition, given that in favorable conditions caridean shrimp larvae shorten their development, we may infer that the cultivation environment, in which larvae developed in the present work, was appropriate, because almost all zoeae VIII kept on brackish water underwent metamorphosis directly to post-larvae and did not go through zoeae IX stage.