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Sample records for dynamic locomotor capabilities

  1. Dynamic locomotor capabilities revealed by early dinosaur trackmakers from southern Africa.

    Directory of Open Access Journals (Sweden)

    Jeffrey A Wilson

    Full Text Available BACKGROUND: A new investigation of the sedimentology and ichnology of the Early Jurassic Moyeni tracksite in Lesotho, southern Africa has yielded new insights into the behavior and locomotor dynamics of early dinosaurs. METHODOLOGY/PRINCIPAL FINDINGS: The tracksite is an ancient point bar preserving a heterogeneous substrate of varied consistency and inclination that includes a ripple-marked riverbed, a bar slope, and a stable algal-matted bar top surface. Several basal ornithischian dinosaurs and a single theropod dinosaur crossed its surface within days or perhaps weeks of one another, but responded to substrate heterogeneity differently. Whereas the theropod trackmaker accommodated sloping and slippery surfaces by gripping the substrate with its pedal claws, the basal ornithischian trackmakers adjusted to the terrain by changing between quadrupedal and bipedal stance, wide and narrow gauge limb support (abduction range = 31 degrees , and plantigrade and digitigrade foot posture. CONCLUSIONS/SIGNIFICANCE: The locomotor adjustments coincide with changes in substrate consistency along the trackway and appear to reflect 'real time' responses to a complex terrain. It is proposed that these responses foreshadow important locomotor transformations characterizing the later evolution of the two main dinosaur lineages. Ornithischians, which shifted from bipedal to quadrupedal posture at least three times in their evolutionary history, are shown to have been capable of adopting both postures early in their evolutionary history. The substrate-gripping behavior demonstrated by the early theropod, in turn, is consistent with the hypothesized function of pedal claws in bird ancestors.

  2. Dynamic Capabilities

    DEFF Research Database (Denmark)

    Grünbaum, Niels Nolsøe; Stenger, Marianne

    2013-01-01

    The findings reveal a positive relationship between dynamic capabilities and innovation performance in the case enterprises, as we would expect. It was, however, not possible to establish a positive relationship between innovation performance and profitability. Nor was there any positive...... relationship between dynamic capabilities and profitability....

  3. Dynamic Capabilities and Performance

    DEFF Research Database (Denmark)

    Wilden, Ralf; Gudergan, Siegfried P.; Nielsen, Bo Bernhard

    2013-01-01

    are contingent on the competitive intensity faced by firms. Our findings demonstrate the performance effects of internal alignment between organizational structure and dynamic capabilities, as well as the external fit of dynamic capabilities with competitive intensity. We outline the advantages of PLS...

  4. Dynamic capabilities, Marketing Capability and Organizational Performance

    Directory of Open Access Journals (Sweden)

    Adriana Roseli Wünsch Takahashi

    2017-01-01

    Full Text Available The goal of the study is to investigate the influence of dynamic capabilities on organizational performance and the role of marketing capabilities as a mediator in this relationship in the context of private HEIs in Brazil. As a research method we carried out a survey with 316 IES and data analysis was operationalized with the technique of structural equation modeling. The results indicate that the dynamic capabilities have influence on organizational performance only when mediated by marketing ability. The marketing capability has an important role in the survival, growth and renewal on educational services offerings for HEIs in private sector, and consequently in organizational performance. It is also demonstrated that mediated relationship is more intense for HEI with up to 3,000 students and other organizational profile variables such as amount of courses, the constitution, the type of institution and type of education do not significantly alter the results.

  5. Fluctuation-Driven Neural Dynamics Reproduce Drosophila Locomotor Patterns.

    Directory of Open Access Journals (Sweden)

    Andrea Maesani

    2015-11-01

    Full Text Available The neural mechanisms determining the timing of even simple actions, such as when to walk or rest, are largely mysterious. One intriguing, but untested, hypothesis posits a role for ongoing activity fluctuations in neurons of central action selection circuits that drive animal behavior from moment to moment. To examine how fluctuating activity can contribute to action timing, we paired high-resolution measurements of freely walking Drosophila melanogaster with data-driven neural network modeling and dynamical systems analysis. We generated fluctuation-driven network models whose outputs-locomotor bouts-matched those measured from sensory-deprived Drosophila. From these models, we identified those that could also reproduce a second, unrelated dataset: the complex time-course of odor-evoked walking for genetically diverse Drosophila strains. Dynamical models that best reproduced both Drosophila basal and odor-evoked locomotor patterns exhibited specific characteristics. First, ongoing fluctuations were required. In a stochastic resonance-like manner, these fluctuations allowed neural activity to escape stable equilibria and to exceed a threshold for locomotion. Second, odor-induced shifts of equilibria in these models caused a depression in locomotor frequency following olfactory stimulation. Our models predict that activity fluctuations in action selection circuits cause behavioral output to more closely match sensory drive and may therefore enhance navigation in complex sensory environments. Together these data reveal how simple neural dynamics, when coupled with activity fluctuations, can give rise to complex patterns of animal behavior.

  6. Unpacking dynamic capability : a design perspective

    NARCIS (Netherlands)

    Mulders, D.E.M.; Romme, A.G.L.; Bøllingtoft, A.; Håkonsson, D.D.; Nielsen, J.F.; Snow, C.C; Ulhøi, J.

    2009-01-01

    This chapter reviews the dynamic capability literature to explore relationships between definition, operationalization, and measurement of dynamic capability. Subsequently, we develop a design-oriented approach toward dynamic capability that distinguishes between design rules, recurrent patterns of

  7. Dynamic capabilities and network benefits

    Directory of Open Access Journals (Sweden)

    Helge Svare

    2017-01-01

    Full Text Available The number of publicly funded initiatives to establish or strengthen networks and clusters, in order to enhance innovation, has been increasing. Returns on such investments vary, and the aim of this study is to explore to what extent the variation in benefits for firms participating in networks or clusters can be explained by their dynamic capabilities (DC. Based on survey data from five Norwegian networks, the results suggest that firms with higher DC are more successful in harvesting the potential benefits of being member of a network.

  8. Distinctive Dynamic Capabilities for New Business Creation

    DEFF Research Database (Denmark)

    Rosenø, Axel; Enkel, Ellen; Mezger, Florian

    2013-01-01

    This study examines the distinctive dynamic capabilities for new business creation in established companies. We argue that these are very different from those for managing incremental innovation within a company's core business. We also propose that such capabilities are needed in both slow...... and fast-paced industries, and that similarities exist across industries. Hence, the study contributes to dynamic capabilities literature by: 1) identifying the distinctive dynamic capabilities for new business creation; 2) shifting focus away from dynamic capabilities in environments characterised by high...... clock-speed and uncertainty towards considering dynamic capabilities for the purpose of developing new businesses, which also implies a high degree of uncertainty. Based on interviews with 33 companies, we identify distinctive dynamic capabilities for new business creation, find that dynamic...

  9. Technological Dynamics and Social Capability

    DEFF Research Database (Denmark)

    Fagerberg, Jan; Feldman, Maryann; Srholec, Martin

    2014-01-01

    for the sample as a whole between 1998 and 2008. The results indicate that social capabilities, such as well-developed public knowledge infrastructure, an egalitarian distribution of income, a participatory democracy and prevalence of public safety condition the growth of technological capabilities. Possible...

  10. Knowledge Perspectives on Advancing Dynamic Capability

    NARCIS (Netherlands)

    van Reijsen, J.

    2014-01-01

    Dynamic Capability is the organizational capacity to timely adapt to a changing market environment by reconfiguring resources and routines in order to stay competitive. Although dynamic capability is considered the Holy Grail of strategic management, a connection to the knowledge management domain

  11. Understanding dynamic capabilities through knowledge management

    DEFF Research Database (Denmark)

    Nielsen, Anders Paarup

    2006-01-01

    In the paper eight knowledge management activities are identified; knowledge creation, acquisition, capture, assembly, sharing, integration, leverage and exploitation. These activities are assembled into the three dynamic capabilities of knowledge development, knowledge (re......)combination and knowledge use. The dynamic capabilities and the associated knowledge management activities create flows to and from the firm’s stock of knowledge and they support the creation and use of organizational capabilities....

  12. Quantumness-generating capability of quantum dynamics

    Science.gov (United States)

    Li, Nan; Luo, Shunlong; Mao, Yuanyuan

    2018-04-01

    We study quantumness-generating capability of quantum dynamics, where quantumness refers to the noncommutativity between the initial state and the evolving state. In terms of the commutator of the square roots of the initial state and the evolving state, we define a measure to quantify the quantumness-generating capability of quantum dynamics with respect to initial states. Quantumness-generating capability is absent in classical dynamics and hence is a fundamental characteristic of quantum dynamics. For qubit systems, we present an analytical form for this measure, by virtue of which we analyze several prototypical dynamics such as unitary dynamics, phase damping dynamics, amplitude damping dynamics, and random unitary dynamics (Pauli channels). Necessary and sufficient conditions for the monotonicity of quantumness-generating capability are also identified. Finally, we compare these conditions for the monotonicity of quantumness-generating capability with those for various Markovianities and illustrate that quantumness-generating capability and quantum Markovianity are closely related, although they capture different aspects of quantum dynamics.

  13. The Locomotor Capabilities Index; validity and reliability of the Swedish version in adults with lower limb amputation

    Directory of Open Access Journals (Sweden)

    Andersson Ingemar H

    2009-05-01

    Full Text Available Abstract Background The Locomotor Capabilities Index (LCI is a validated measure of lower-limb amputees' ability to perform activities with prosthesis. We have developed the LCI Swedish version and evaluated its validity and reliability. Methods Cross-cultural adaptation to Swedish included forward/backward translations and field testing. The Swedish LCI was then administered to 144 amputees (55 women, mean age 74 (40–93 years, attending post-rehabilitation prosthetic training. Construct validity was assessed by examining the relationship between the LCI and Timed "Up-and-Go" (TUG test and between the LCI and EQ-5D health utility index in 2 subgroups of 40 and 20 amputees, respectively. Discriminative validity was assessed by comparing scores in different age groups and in unilateral and bilateral amputees. Test-retest reliability (1–2 weeks was evaluated in 20 amputees (14 unilateral. Results The Swedish LCI showed good construct convergent validity, with high correlation with the TUG (r = -0.75 and the EQ-5D (r = 0.84, and discriminative validity, with significantly worse mean scores for older than younger and for bilateral than unilateral amputees (p Conclusion The Swedish version of the LCI demonstrated good validity and internal consistency in adult amputees. Test-retest reliability in a small subsample appears to be acceptable. The high ceiling effect of the LCI may imply that it would be most useful in assessing amputees with low to moderate functional abilities.

  14. Institutional Change, Strategic Orientation and Dynamic Capabilities

    DEFF Research Database (Denmark)

    Li, Ming Hua

    2012-01-01

    research streams including the resource-based view, institutional and organizational theory frameworks, as well as the dynamic capabilities perspective, we suggest that institutional change in China serves a formative role in the development of firm strategic orientation and dynamic capabilities leading......The phenomenon of systematic institutional change in many developing countries can produce enduring transformations in the strategic orientation and organization of domestic firms. Such changes may impact the formation of their dynamic capabilities and adaptive learning which can translate...... into visible differences in their internationalization strategies and pathways. Using China as an illustrative example of a transitioning economy experiencing upsurges in outward FDI, this study develops a theoretical framework to explain how institutional transformation at various levels of government led...

  15. Dynamic capabilities, creative action, and poetics

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    Donald MacLean

    2017-05-01

    Full Text Available Research on dynamic capabilities explores how businesses change enables enterprises to remain competitive. However, theory on dynamic capabilities still struggles to capture novelty, the essence of change. This study argues that a full understanding of strategic change requires us to sharpen our focus on real people and experiences; in turn, we must incorporate other faculties, which almost always operate alongside our logical ones, into our theory. We must pay more attention to the “non­-rational” sides of ourselves—including, but not limited to, our imaginations, intuitions, attractions, biographies, preferences, and aesthetic faculties and capabilities. We argue that all such faculties, on the one hand, are central to our abilities to comprehend and cope with complexity and, on the other hand, foster novel understandings, potential responses, and social creativity. This study intro­duces the possibility of an alternative form of inquiry that highlights the role of poetic faculties in strategic behavior and change.

  16. Dynamic capabilities from an institutionalist viewpoint

    Directory of Open Access Journals (Sweden)

    José Bonfim Albuquerque Filho

    Full Text Available Abstract The purpose of this paper is to elucidate the effects of strategic, technical and institutional response, in the perspective of dynamic capability facing environmental changes, considering that the literature has few references on how institutional factors contribute to a firm’s dynamic capabilities. A case study was conducted on the oldest journalistic enterprise in Brazil. It was found that the organizational practices with dynamic capabilities were conditioned by mechanisms and factors that have extrapolated intentions, expectations, and planning skills of the firm’s own Board of Directors. The new social structure found in the organization is based on the interpretations of the journalists themselves, regarding the social reality of the field of journalism, was supported by the coherent interpretative schemata of some managers in order to reduce the uncertainty caused by institutional demands of the rapidly changing reading habits of people. The study revealed that strategic practices such as making the newspaper known at schools, development of a digital newspaper, showed the influence of institutions as a new normative order, social responsibility, greater legitimacy, and at the same time, a higher capacity of the organization to adapt to its business environment. These aspects, reflect a cultural structure that is reproduced at the company in its practices for the continuous use of new technologies and new social demands.

  17. Gendering dynamic capabilities in micro firms

    Directory of Open Access Journals (Sweden)

    Yevgen Bogodistov

    2017-05-01

    Full Text Available Gender issues are well-researched in the general management literature, particular in studies on new ventures. Unfortunately, gender issues have been largely ignored in the dynamic capabilities litera­ture. We address this gap by analyzing the effects of gender diversity on dynamic capabilities among micro firms. We consider the gender of managers and personnel in 124 Ukrainian tourism micro firms. We examine how a manager’s gender affects the firm’s sensing capacities and investigate how it moderates team gender diversity’s impact on sensing capacities. We also investigate how person­nel composition impacts seizing and reconfiguration capacities. We find that female managers have several shortcomings concerning a firm’s sensing capacity but that personnel gender diversity increa­ses this capacity. Team gender diversity has positive effects on a firm’s seizing and reconfiguration abilities. Our study advances research on gender diversity and its impact on firm capabilities and illustrates its relevance for staffing practices in micro firms.

  18. Dynamic capabilities and innovation capabilities: The case of the ‘Innovation Clinic’

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    Fred Strønen

    2017-01-01

    Full Text Available In this explorative study, we investigate the relationship between dynamic capabilities and innovation capabilities. Dynamic capabilities are at the core of strategic management in terms of how firms can ensure adaptation to changing environments over time. Our paper follows two paths of argumentation. First, we review and discuss some major contributions to the theories on ordinary capabilities, dynamic capabilities, and innovation capabilities. We seek to identify different understandings of the concepts in question, in order to clarify the distinctions and relationships between dynamic capabilities and innovation capabilities. Second, we present a case study of the ’Innovation Clinic’ at a major university hospital, including four innovation projects. We use this case study to explore and discuss how dynamic capabilities can be extended, as well as to what extent innovation capabilities can be said to be dynamic. In our conclusion, we discuss the conditions for nurturing ‘dynamic innovation capabilities’ in organizations.

  19. Uncovering Dynamic Capabilities for Service Innovation: Conceptualization and Measurement

    NARCIS (Netherlands)

    Janssen, M.; Alexiev, A.S.; Castaldi, C.; Den Hertog, P.

    2013-01-01

    The dynamic capabilities view (DCV) is in need of a solid empirical grounding. Existing attempts to identify the organizational behaviour (or microfoundations) on which dynamic capabilities rely are largely biased towards manufacturing. Thereby, these conceptualizations overlook some of the aspects

  20. AMBIDEXTER Dynamics and Self-Regulation Capability

    International Nuclear Information System (INIS)

    Oh, Se Kee; Lee, Young Joon; Ham, Tae Kyu; Seo, Myung Hwan; Hong, Sung Taek; Kwon, Tae An

    2009-01-01

    Safety-related events in a nuclear reactor system are mostly incurred by sudden imbalance between their heat source and sink behaviors. Controllability and resiliency are assessed if the system be safely recoverable from the imbalance. Inherent safety characteristics of the reactor should be an ideal design philosophy in this aspect. The AMBIDEXTER safety design was explored with maximum reliance on counteractive responses by the system itself. As for the realization, negative reactivity feedback and fail-safe criteria are the fundamental considerations. Details of how to implement them in the design can be found in the paper accompanied. the reactor and the primary heat exchanger are integrated into a closed loop in the vessel. The fuel salt flows downwardly in the outer core region, gains fission heat and then, rises upwardly through the central inner core region where resonance absorbers face better conversion chance. In the primary heat exchanger, heat transfer between the tube-side fuel salt and the shell-side coolant salt is made. For chemical processing, part of the fuel salt flow is discharged from the heat exchanger and returns to the reactor through bypass line. This paper examines the dynamic performances of the AMBIDEXTER reactor system to investigate the range of its self-regulation capability and safety impacts

  1. Global dynamics, capabilities and the crisis

    Czech Academy of Sciences Publication Activity Database

    Fagerberg, J.; Srholec, Martin

    2016-01-01

    Roč. 26, č. 4 (2016), s. 765-784 ISSN 0936-9937 Institutional support: PRVOUK-P23 Keywords : technological capabilities * social capabilities * competitiveness Subject RIV: AH - Economics Impact factor: 0.862, year: 2016

  2. Dynamic capabilities and innovation management: a conceptual approach

    Directory of Open Access Journals (Sweden)

    Jose Javier Aguilar Zambrano

    2006-07-01

    Full Text Available Organizational capabilities are those behavioral routines oriented to develop a specific task (NELSON; WINTER, 1982. These capabilities define what the company knows to do and how must to do it. Nevertheless, the repetitive character of these capabilities could be producing stopped processes (METCALFE, 1995 which both limit the generation of new capabilities and diminishing the dynamism in the production, reproduction and reconfiguration of new capabilities (TEECE; PISANO, 1997. This article compares and analyzes different theoretical-conceptual perspectives for generation and reconfiguration of technological capabilities within an organization. Additionally this article suggests that dynamic capabilities to make feasible innovation processes within an organization. The general concept of dynamic capacities will be used like driver of changes to produce and reconfigurate capabilities in the organization. The glance of the dynamic capabilities allows understanding the complexity of the creation, development and use of capabilities. This understanding could constitute material fundamental to manage learning processes and organizational change oriented to innovation.

  3. Towards a dynamic concept of alliance capability

    OpenAIRE

    SLUYTS, Kim; MARTENS, Rudy; MATTHYSSENS, Paul

    2008-01-01

    This paper has a threefold purpose. First, we offer a literature review on alliance capability based on strategic and competence based management literature. Second, we extend existing literature on alliance capability by breaking this concept down into five sub capabilities, which are each linked to a stage of the alliance life cycle. Finally, we suggest how firms can support these capabilities through structural, technological and people-related tools and techniques. We argue that current l...

  4. Dynamic Capabilities and Project Management in Small Software Companies

    DEFF Research Database (Denmark)

    Nørbjerg, Jacob; Nielsen, Peter Axel; Persson, John Stouby

    2017-01-01

    A small software company depends on its capability to adapt to rapid technological and other changes in its environment—its dynamic capabilities. In this paper, we argue that to evolve and maintain its dynamic capabilities a small software company must pay attention to the interaction between...... dynamic capabilities at different levels of the company — particularly between the project management and the company levels. We present a case study of a small software company and show how successful dynamic capabilities at the company level can affect project management in small software companies...

  5. Global dynamics, capabilities and the crisis

    Czech Academy of Sciences Publication Activity Database

    Fagerberg, J.; Srholec, Martin

    2016-01-01

    Roč. 26, č. 4 (2016), s. 765-784 ISSN 0936-9937 R&D Projects: GA ČR GAP402/10/2310 Institutional support: RVO:67985998 Keywords : technological capabilities * social capabilities * competitiveness Subject RIV: AH - Economics Impact factor: 0.862, year: 2016

  6. Dynamic clearance measure to evaluate locomotor and perceptuo-motor strategies used for obstacle circumvention in a virtual environment.

    Science.gov (United States)

    Darekar, Anuja; Lamontagne, Anouk; Fung, Joyce

    2015-04-01

    Circumvention around an obstacle entails a dynamic interaction with the obstacle to maintain a safe clearance. We used a novel mathematical interpolation method based on the modified Shepard's method of Inverse Distance Weighting to compute dynamic clearance that reflected this interaction as well as minimal clearance. This proof-of-principle study included seven young healthy, four post-stroke and four healthy age-matched individuals. A virtual environment designed to assess obstacle circumvention was used to administer a locomotor (walking) and a perceptuo-motor (navigation with a joystick) task. In both tasks, participants were asked to navigate towards a target while avoiding collision with a moving obstacle that approached from either head-on, or 30° left or right. Among young individuals, dynamic clearance did not differ significantly between obstacle approach directions in both tasks. Post-stroke individuals maintained larger and smaller dynamic clearance during the locomotor and the perceptuo-motor task respectively as compared to age-matched controls. Dynamic clearance was larger than minimal distance from the obstacle irrespective of the group, task and obstacle approach direction. Also, in contrast to minimal distance, dynamic clearance can respond differently to different avoidance behaviors. Such a measure can be beneficial in contrasting obstacle avoidance behaviors in different populations with mobility problems. Copyright © 2015 Elsevier B.V. All rights reserved.

  7. Dynamic capabilities and innovation: a Multiple-Case Study

    OpenAIRE

    Bravo Ibarra, Edna Rocío; Mundet Hiern, Joan; Suñé Torrents, Albert

    2009-01-01

    After a detailed survey of the scientific literature, it was found that several characteristics of dynamic capabilities were similar to those of innovation capability. Therefore, with a deeper study of the first ones, it could be possible to design a model aimed to structure innovation capability. Thus, this work presents a conceptual model, where the innovation capability is shown as result of three processes: knowledge absorption and creation capability, knowledge integration and knowledge ...

  8. The Evolving Dynamics of Organizational Capabilities

    DEFF Research Database (Denmark)

    Augier, Mie-Sophia

    2004-01-01

    In this paper, Mie Augier provides a rich description of the intellectual traditions, the signifi-cant people and academic institutions that in some way or another made a difference to Davis Teece's own intellectual development. In this sense, it is a dynamic account of the emerging career...

  9. Implementing Firm Dynamic Capabilities Through the Concept Design Process

    DEFF Research Database (Denmark)

    Nedergaard, Nicky; Jones, Richard

    2011-01-01

    It is well understood that firms operating in highly dynamic and fluid markets need to possess strong dynamic capabilities of sensing (market trajectories), seizing (to capitalise on these trajectories), and transformation (in order to implement sustainable strategies). Less understood is how firms...... actually implement these capabilities. A conceptual model showing how managing concept design processes can help firms systematically develop dynamic capabilities and help bridge the gap between the market-oriented and resource-focused strategic perspectives is presented. By placing this model in a design......-driven innovation perspective three theoretical propositions is derived explicating both the paper’s implementation approach to dynamic capabilities as well as new ways of understanding these capabilities. Concluding remarks are made discussing both the paper’s contribution to the strategic marketing literature...

  10. [Age-specific dynamics of mental working capacity in different regimens of locomotor activity].

    Science.gov (United States)

    Miakotnykh, V V; Khodasevich, L S

    2012-01-01

    The present study included a total of 392 practically healthy men aged between 40 and 79 years differing in the character of routine locomotor activity and the training status (from masters of sport of international grade to the subjects who had never been engaged in sporting activities). They were divided into 4 groups each comprised of subjects ranged by age with a ten-year interval. Their mental working capacity was estimated from the results of the correction test. The study demonstrated that the subjects characterized by a high level of day-to-day locomotor activity have higher indices of attention intensity and information processing speed compared with the age-matched ones leading a relatively sedentary lifestyle. Moreover, they have better chances to retain the mental working capacity up to the age of 70 years.

  11. Supporting Dynamic Ad hoc Collaboration Capabilities

    CERN Document Server

    Agarwal, D

    2003-01-01

    Modern HENP experiments such as CMS and Atlas involve as many as 2000 collaborators around the world. Collaborations this large will be unable to meet often enough to support working closely together. Many of the tools currently available for collaboration focus on heavy-weight applications such as videoconferencing tools. While these are important, there is a more basic need for tools that support connecting physicists to work together on an ad hoc or continuous basis. Tools that support the day-to-day connectivity and underlying needs of a group of collaborators are important for providing light-weight, non-intrusive, and flexible ways to work collaboratively. Some example tools include messaging, file-sharing, and shared plot viewers. An important component of the environment is a scalable underlying communication framework. In this paper we will describe our current progress on building a dynamic and ad hoc collaboration environment and our vision for its evolution into a HENP collaboration environment.

  12. Supporting Dynamic Ad hoc Collaboration Capabilities

    International Nuclear Information System (INIS)

    Agarwal, Deborah A.; Berket, Karlo

    2003-01-01

    Modern HENP experiments such as CMS and Atlas involve as many as 2000 collaborators around the world. Collaborations this large will be unable to meet often enough to support working closely together. Many of the tools currently available for collaboration focus on heavy-weight applications such as videoconferencing tools. While these are important, there is a more basic need for tools that support connecting physicists to work together on an ad hoc or continuous basis. Tools that support the day-to-day connectivity and underlying needs of a group of collaborators are important for providing light-weight, non-intrusive, and flexible ways to work collaboratively. Some example tools include messaging, file-sharing, and shared plot viewers. An important component of the environment is a scalable underlying communication framework. In this paper we will describe our current progress on building a dynamic and ad hoc collaboration environment and our vision for its evolution into a HENP collaboration environment

  13. Blind spots of dynamic capabilities: A systems theoretic perspective

    Directory of Open Access Journals (Sweden)

    Robert Burisch

    2016-05-01

    Full Text Available Dynamic capabilities remain one of the most popular, but also one of the most controversial topics in current knowledge and innovation research. This study exposes strengths and weaknesses of existing conceptualizations of dynamic capabilities by using a systems theoretic lens. Systems theory suggests that organizations operate in environments they cannot fully understand. Thus, organizational action patterns inevitably involve simplification, selectivity and uncertainty leading to inherent blind spots in every kind of strategic action. As the resulting insight, fully flexible organizational capabilities might not be achievable and continuous adaptation to every kind of environmental change cannot be possible from a systems theoretic perspective. Accordingly, this work discusses empirical difficulties that derive from the preceding argumentation and outlines a corresponding re-conceptualization of the dynamic capabilities concept.

  14. Neuronal control of locomotor handedness in Drosophila.

    Science.gov (United States)

    Buchanan, Sean M; Kain, Jamey S; de Bivort, Benjamin L

    2015-05-26

    Genetically identical individuals display variability in their physiology, morphology, and behaviors, even when reared in essentially identical environments, but there is little mechanistic understanding of the basis of such variation. Here, we investigated whether Drosophila melanogaster displays individual-to-individual variation in locomotor behaviors. We developed a new high-throughout platform capable of measuring the exploratory behavior of hundreds of individual flies simultaneously. With this approach, we find that, during exploratory walking, individual flies exhibit significant bias in their left vs. right locomotor choices, with some flies being strongly left biased or right biased. This idiosyncrasy was present in all genotypes examined, including wild-derived populations and inbred isogenic laboratory strains. The biases of individual flies persist for their lifetime and are nonheritable: i.e., mating two left-biased individuals does not yield left-biased progeny. This locomotor handedness is uncorrelated with other asymmetries, such as the handedness of gut twisting, leg-length asymmetry, and wing-folding preference. Using transgenics and mutants, we find that the magnitude of locomotor handedness is under the control of columnar neurons within the central complex, a brain region implicated in motor planning and execution. When these neurons are silenced, exploratory laterality increases, with more extreme leftiness and rightiness. This observation intriguingly implies that the brain may be able to dynamically regulate behavioral individuality.

  15. “Coupled processes” as dynamic capabilities in systems integration

    Directory of Open Access Journals (Sweden)

    Milton de Freitas Chagas Jr.

    2017-05-01

    Full Text Available The dynamics of innovation in complex systems industries is becoming an independent research stream. Apart from conventional uncertainties related to commerce and technology, complex-system industries must cope with systemic uncertainty. This paper’s objective is to analyze evolving technological paths from one product generation to the next through two case studies in the Brazilian aerospace indus­try, considering systems integration as an empirical instantiation of dynamic capabilities. A proposed “coupled processes” model intertwines two organizational processes regarded as two levels of dynamic capabilities: new product and technological developments. The model addresses the role of emergent properties in shaping a firm’s technological base. Moreover, it uses a technology readiness level to unveil systems integration business tricks and as a decision-making yardstick. The “coupled processes” model is revealed as a set of dynamic capabilities presenting ambidexterity in complex systems indus­tries, a finding that may be relevant for newly industrialized economies.

  16. How dynamic capabilities drive performance in the Indian IT industry

    DEFF Research Database (Denmark)

    Holzweber, Markus; Mattsson, Jan; Chadee, Doren

    2012-01-01

    This study examines key issues and effects of capability management on a fast-growing area of knowledge-intensive global business services – IT outsourcing and offshoring. An exploratory study of Indian companies providing complex process-oriented offshore IT services to their global customers...... is undertaken. The analysis of the data related to the service provider side shows that developing dynamic capabilities is strongly driven by management and top-clients and results in the development of business processes and in establishing a strategic partnership with the client organization. Key findings...

  17. Dynamic capability in an under-researched cultural environment

    Directory of Open Access Journals (Sweden)

    Fatemeh Rezaee

    2016-02-01

    Full Text Available During the past few years, dynamic capability (DC has been considered as an important issue in banking industry. This paper presents a survey on dynamic capability and its role on reaching sustainable competitive advantage (SCA within Mellat bank of Iran (MBI. A valid research instrument is utilized to conduct a survey among 150 managers from MBI. The study utilizes structural equation modelling to examine different hypotheses based on an integrated model of DC and SCA. According to literature studies, expert opinions and exploratory factor analysis, DC is classified into sensing, learning, reconfiguration, and coordination. Furthermore, SCA of the banking industry is classified into three dimensions: market, customer, and financial performance. The results indicate that DC had the greatest effect on the market centered, while it had the least influence on the customer centered.

  18. The Exploration of Design Driven Innovation as a Dynamic Capability

    Directory of Open Access Journals (Sweden)

    Philips Kembaren

    2012-01-01

    Full Text Available Innovation enables companies to attain consistent organic growth that brings benefits to stakeholders. Designthinking approach in innovation has been emergent to be an alternative to technological development path inorder to generate competitive and successful product or service in the market place. Design driven innovationcombines functional and semantic dimensions of products or services in the marketplace. Previous researchhas recently revealed practices of design driven innovation in various industries. However, little is known tothe extent that companies in Indonesia practicing design driven innovation. A theoretical framework withperspective from dynamic capability theoretical lens and guided by Dubin’s theory building methodology isproposed to explain the constructs and role of design in the process of innovation. The research is expected tocontribute a new construct to the existing framework, namely construct that related to how we could assessthe value of the design-driven innovation output, perceived by the costumers.Keywords: design driven innovation, dynamic capabilities, theory building

  19. Locomotor Stability in a Model Swimmer: Coupling Fluid Dynamics, Neurophysiology and Muscle Mechanics

    Science.gov (United States)

    2017-07-05

    SECURITY CLASSIFICATION OF: We use multiscale modeling and computational fluid dynamics to examine the stability of a swimming organism in the face of...information is estimated to average 1 hour per response, including the time for reviewing instructions, searching existing data sources, gathering and

  20. Dynamic Capabilities of Universities in the Knowledge Economy

    Directory of Open Access Journals (Sweden)

    Ruxandra BEJINARU

    2017-12-01

    Full Text Available The purpose of this paper is to analyze how universities can develop dynamic capabilities based on their strategic resources in order to increase their competitiveness in the knowledge economy. ”Dynamic capabilities” is a concept introduced by Teece, Pisano, and Shuen (1997 to emphasize the managerial capacity of a given organization of using efficiently its strategic resources in transforming opportunities in business success. They reflect the capacity of the organization to sense, seize, adapt to the changing environment. For a university, the most important strategic resources are information, knowledge, and ideas which constitute its intellectual capital. The present paper is analyzing critically these strategic resources of a university and the necessary conditions to develop dynamic capabilities in order to use efficiently these resources in a turbulent economic environment. Universities are in the knowledge economy the most important hubs for knowledge creation and its transfer to the students, as well as to their communities. At the same time, professors contribute to the development of the generic thinking skills of their students to help them for employability in a future with many new jobs and new business activities.

  1. Dynamic managerial capability of technology-based international new ventures

    DEFF Research Database (Denmark)

    Altshuler, Liliya

    2014-01-01

    case study of a technology-based INV conducted over the period of 3.5 years, starting 8 years into the firm’s history. This unique design has enabled close observation of the specific events and challenges the firm has been facing after its initial success, and of the aspects in the firm’s management...... to resource availability. The study takes the dynamic capability perspective and focuses on INVs’ management, which are seen as founders and builders of the processes, rules and structures that lay the basis for long-term competitive advantage for such firms. Based on the findings, specific aspects...

  2. Nuclear Hybrid Energy System Modeling: RELAP5 Dynamic Coupling Capabilities

    Energy Technology Data Exchange (ETDEWEB)

    Piyush Sabharwall; Nolan Anderson; Haihua Zhao; Shannon Bragg-Sitton; George Mesina

    2012-09-01

    The nuclear hybrid energy systems (NHES) research team is currently developing a dynamic simulation of an integrated hybrid energy system. A detailed simulation of proposed NHES architectures will allow initial computational demonstration of a tightly coupled NHES to identify key reactor subsystem requirements, identify candidate reactor technologies for a hybrid system, and identify key challenges to operation of the coupled system. This work will provide a baseline for later coupling of design-specific reactor models through industry collaboration. The modeling capability addressed in this report focuses on the reactor subsystem simulation.

  3. Innovation and dynamic capabilities of the firm: Defining an assessment model

    Directory of Open Access Journals (Sweden)

    André Cherubini Alves

    2017-05-01

    Full Text Available Innovation and dynamic capabilities have gained considerable attention in both academia and practice. While one of the oldest inquiries in economic and strategy literature involves understanding the features that drive business success and a firm’s perpetuity, the literature still lacks a comprehensive model of innovation and dynamic capabilities. This study presents a model that assesses firms’ innovation and dynamic capabilities perspectives based on four essential capabilities: development, operations, management, and transaction capabilities. Data from a survey of 1,107 Brazilian manufacturing firms were used for empirical testing and discussion of the dynamic capabilities framework. Regression and factor analyses validated the model; we discuss the results, contrasting with the dynamic capabilities’ framework. Operations Capability is the least dynamic of all capabilities, with the least influence on innovation. This reinforces the notion that operations capabilities as “ordinary capabilities,” whereas management, development, and transaction capabilities better explain firms’ dynamics and innovation.

  4. Mechanism of supply chain coordination cased on dynamic capability framework-the mediating role of manufacturing capabilities

    Directory of Open Access Journals (Sweden)

    Tiantian Gao

    2014-10-01

    Full Text Available Purpose: A critical issue has been absent from the conversation on supply chain coordination: how supply chain coordination influence the enterprise performance. This research proposes a new vision to research the performance mechanism of supply chain coordination capability as a dynamic capability. Manufacturing capabilities are existed as mediating role. Design/methodology/approach: Data from International Manufacturing Strategy Survey in 2009 is used to verify the mediating model by hierarchical regression analysis. Findings: The results show that supply chain coordination impacts the enterprise performance positively and indirect impacts the enterprise performance through quality, cost, flexibility. Research implications: This study presents an overview of the impact of supply chain coordination and manufacturing capabilities on enterprise performance, giving grasp for further research of the relationships that exist between them. Originality/value: This finding integrates insights from previous research in dynamic capability framework and supply chain management into a generalization and extension of the performance mechanism in manufacturing enterprises.

  5. Technological dynamics and social capability: US states and European nations

    Czech Academy of Sciences Publication Activity Database

    Fagerberg, J.; Feldman, M.; Srholec, Martin

    2014-01-01

    Roč. 14, č. 2 (2014), s. 313-337 ISSN 1468-2702 Institutional support: PRVOUK-P23 Keywords : innovation * technological capability * social capability Subject RIV: AH - Economics Impact factor: 2.494, year: 2014

  6. Technological dynamics and social capability: US states and European nations

    Czech Academy of Sciences Publication Activity Database

    Fagerberg, J.; Feldman, M.; Srholec, Martin

    2014-01-01

    Roč. 14, č. 2 (2014), s. 313-337 ISSN 1468-2702 R&D Projects: GA ČR GAP402/10/2310 Institutional support: RVO:67985998 Keywords : innovation * technological capability * social capability Subject RIV: AH - Economics Impact factor: 2.494, year: 2014

  7. "COUPLED PROCESSES" AS DYNAMIC CAPABILITIES IN SYSTEMS INTEGRATION

    OpenAIRE

    Chagas Jr, Milton de Freitas; Leite, Dinah Eluze Sales; Jesus, Gabriel Torres de

    2017-01-01

    ABSTRACT The dynamics of innovation in complex systems industries is becoming an independent research stream. Apart from conventional uncertainties related to commerce and technology, complex-system industries must cope with systemic uncertainty. This paper's objective is to analyze evolving technological paths from one product generation to the next through two case studies in the Brazilian aerospace industry, considering systems integration as an empirical instantiation of dynamic capabilit...

  8. Organizing for Flexibility: Addressing Dynamic Capabilities and Organization Design

    OpenAIRE

    van der Weerdt, Niels; Volberda, Henk; Verwaal, Ernst; Stienstra, Marten

    2014-01-01

    The increasingly dynamic nature of organizational environments has led the research community to study organizational flexibility. Although the research literature stresses the complexity of the organizational flexibility construct, it lacks a comprehensive empirical study addressing the relationships among various dimensions of organizational flexibility. This chapter develops a theoretical framework specifying the linkages between types of flexibility and organization design characteristics...

  9. Dissolution Dynamic Nuclear Polarization capability study with fluid path

    DEFF Research Database (Denmark)

    Malinowski, Ronja Maja; Lipsø, Hans Kasper Wigh; Lerche, Mathilde Hauge

    2016-01-01

    Signal enhancement by hyperpolarization is a way of overcoming the low sensitivity in magnetic resonance; MRI in particular. One of the most well-known methods, dissolution Dynamic Nuclear Polarization, has been used clinically in cancer patients. One way of ensuring a low bioburden of the hyperp......Signal enhancement by hyperpolarization is a way of overcoming the low sensitivity in magnetic resonance; MRI in particular. One of the most well-known methods, dissolution Dynamic Nuclear Polarization, has been used clinically in cancer patients. One way of ensuring a low bioburden...... of the hyperpolarized product is by use of a closed fluid path that constitutes a barrier to contamination. The fluid path can be filled with the pharmaceuticals, i.e. imaging agent and solvents, in a clean room, and then stored or immediately used at the polarizer. In this study, we present a method of filling...

  10. Intellectual Capital and Organizational Renewal: Building Dynamic Capabilities through People

    Directory of Open Access Journals (Sweden)

    Fabio de Biazzi

    2012-05-01

    Full Text Available This paper seeks to deepen the understanding of management practices adopted by organizations characterizedby significant levels of participation and influence from their employees. Based on the assumption that thesuccessful utilization of such practices is circumstantial, a conceptual framework is proposed identifying theessential elements that should be dynamically aligned to allow organizational success in the long term. Differenttypes of work & participation practices – that arise from the adoption of the dimensions locus of knowledge andlocus of power – support the reasoning on how to align these elements and, consequently, how to lead theorganizational renewal and survival in the long run.

  11. Dynamic Simulation of Human Gait Model With Predictive Capability.

    Science.gov (United States)

    Sun, Jinming; Wu, Shaoli; Voglewede, Philip A

    2018-03-01

    In this paper, it is proposed that the central nervous system (CNS) controls human gait using a predictive control approach in conjunction with classical feedback control instead of exclusive classical feedback control theory that controls based on past error. To validate this proposition, a dynamic model of human gait is developed using a novel predictive approach to investigate the principles of the CNS. The model developed includes two parts: a plant model that represents the dynamics of human gait and a controller that represents the CNS. The plant model is a seven-segment, six-joint model that has nine degrees-of-freedom (DOF). The plant model is validated using data collected from able-bodied human subjects. The proposed controller utilizes model predictive control (MPC). MPC uses an internal model to predict the output in advance, compare the predicted output to the reference, and optimize the control input so that the predicted error is minimal. To decrease the complexity of the model, two joints are controlled using a proportional-derivative (PD) controller. The developed predictive human gait model is validated by simulating able-bodied human gait. The simulation results show that the developed model is able to simulate the kinematic output close to experimental data.

  12. The use of dynamic capabilities to boost innovation in a Brazilian Chemical Company

    Directory of Open Access Journals (Sweden)

    Cristiane Froehlich

    Full Text Available Abstract Dynamic capabilities seek to explain how competitive advantages can be built in rapidly changing environments. This study aims to assess how the application of dynamic capabilities can contribute to the expansion of innovation capabilities. Data was collected on ten semi-structured interviews with executives from a chemical company, and analyzed using qualitative content analysis. Results indicate that the application of dynamic capabilities contributes to the development of innovation capabilities through the consolidation of the first dynamic capability (sensing, which fosters innovation. Sensing can be considered an organizational capability, resulting from the integration between organizational strategies and the innovation practices of the organization as a whole. This study brings the following contributions the need to include a new microfoundation in the sensing capability, which in this study is called ‘processes to manage innovation on a strategic level' and the need to adapt another microfoundation related to the sensing capability, called ‘processes oriented toward collaboration with suppliers to complement and stimulate innovations within the company'. It is suggested that these processes should be reassessed in terms of their potential to generate and complement organizational innovation.

  13. Dynamic capabilities for cooperation in Brazilian multinational and factors determining its management

    Directory of Open Access Journals (Sweden)

    Priscila Rezende da Costa

    2015-05-01

    Full Text Available In the context of emerging companies’ growth, current challenges depend on the local generation of product and process innovations, as well as dynamic capability to generate innovative solutions cooperatively and new globe business models. The objective of this study is to analyse the determining managerial factors for the dynamic capability of cooperation in Brazilian multinationals (BMNs. A survey was conducted with a sample of 60 BMNs, and a structured questionnaire and statistical tests with factorial analysis and Cronbach's alpha were used. The aggregate analysis of the results indicates that BMNs are going through a transitional process between the operational capability of cooperation and the capability for dynamic cooperation, which are relevant to the continuous adaptation of already-established cooperative management routines and the evaluation and incorporation of the relational capability of management practices that consider systemic flows, open innovation and integrate strategic intentionality into cooperative processes.

  14. An Analytical Framework for Miles and Snow Typology and Dynamic Capabilities

    Directory of Open Access Journals (Sweden)

    Tomas Sparano Martins

    2014-03-01

    Full Text Available The literature on dynamic capabilities is confusing, full of overlapping definitions, and contradictions. The theoretical and practical importance of developing and applying dynamic capabilities to sustain competitive advantage in complex external environment is central in studies about strategy nowadays. In this paper, we offer a definition of dynamic capabilities under two aspects: first, it refers to the shifting character of the environment; second, it emphasizes the key role of strategic management in appropriately adapting, integrating, and re-configuring internal and external organizational skills, resources, and functional competences towards a changing environment. This paper aims to clarify the concept of dynamic capabilities, propose an analytical framework that connects this “new” concept to a well known and recognized generic strategic model (Miles and Snow, 1978 and to the concept of sustainable competitive advantage and evolutionary fit. DOI:10.5585/riae.v13i1.1934

  15. Assessing the origins, evolution and prospects of the literature on dynamic capabilities: A bibliometric analysis

    Directory of Open Access Journals (Sweden)

    Gema Albort-Morant

    2018-01-01

    Full Text Available The purpose of this study is to serve as orientation and guidance to academics that are starting or currently developing their research within the field of dynamic capabilities, in order to enhance their knowledge about which are the key scientific journals, authors and articles shaping this topic. This paper presents a bibliometric analysis on dynamic capabilities, making use of the Web of Science database to perform it. This analysis comprises fundamental issues such as (i the number of studies published per year, (ii the countries with the highest rate of productivity, (iii the most prolific and influential authors, (iv assessment of studies citing dynamic capabilities, and (v the most productive journals on dynamic capabilities and recent studies on this topic. Results reveal an exponential growth in the number of publications on dynamic capabilities for the 2000–2012 period. Although, since 2012 this growth has decelerated, the number of publications on this topic remains noteworthy. This study brings useful information for those academics and practitioners attempting to analyze and deepen within this particular field of research, at the same time that provides some insights concerning the future development and progress of the dynamic capabilities topic in the management, business and economics academic literature.

  16. Dynamic Capabilities and Firm Performance: A Case of Two SMEs in Pakistan

    Directory of Open Access Journals (Sweden)

    Qazi Muhammad Moinuddin Abro

    2011-07-01

    Full Text Available This paper investigates the inter-relationship among entrepreneurship, dynamic capabilities and innovation. Entrepreneur\\'s foresights and insights of ICT (Information and Communication Technologies tend to affect their choices of resources and development of dynamic capabilities, leading to different results of innovation. Based on the literature of business innovation and dynamic capabilities, this paper provides a model addressing the links between leadership, with insights and foresights for technology exploration and exploitation, and organizational capabilities of resource integration, learning and transformation to accelerate innovation. A comparative analysis of the two textile manufacturers in Pakistan revealed a cyclical process between the leadership decisions and dynamic capabilities of leveraging ICT for sustained competitiveness in these two SMEs (Small and Medium Sized Enterprises. The result suggests that to build strong capabilities for continuous innovation in today\\'s dynamic business environment, firms need to have leadership with both the attitude and behavior of entrepreneurship, combining the foresight to capture opportunities through ICT and the insight to guide and manage internal resources to achieve ICT-enabled innovation.

  17. Dynamic capabilities

    DEFF Research Database (Denmark)

    Grünbaum, Niels Nolsøe; Stenger, Marianne

    2013-01-01

    enterprises’ internal and external business atmosphere. A sphere dominated, on the positive side, by high product quality, high product innovation, high flexibility, a very low return rate of failed products, a flat organization structure and an involving style of leadership. On the opposite pole...

  18. How do dynamic capabilities transform external technologies into firms’ renewed technological resources? – A mediation model

    DEFF Research Database (Denmark)

    Li-Ying, Jason; Wang, Yuandi; Ning, Lutao

    2016-01-01

    microfoundations of dynamic technological capabilities, mediate the relationship between external technology breadth and firms’ technological innovation performance, based on the resource-based view and dynamic capability view. Using a sample of listed Chinese licensee firms, we find that firms must broadly......How externally acquired resources may become valuable, rare, hard-to-imitate, and non-substitute resource bundles through the development of dynamic capabilities? This study proposes and tests a mediation model of how firms’ internal technological diversification and R&D, as two distinctive...... explore external technologies to ignite the dynamism in internal technological diversity and in-house R&D, which play their crucial roles differently to transform and reconfigure firms’ technological resources....

  19. Organizational reputation risk management as a component of the dynamic capabilities management process1

    Directory of Open Access Journals (Sweden)

    Krzakiewicz Kazimierz

    2015-05-01

    Full Text Available Intangible assets, such as reputation, brand value, strategic position, alliances, knowledge, human capital, play an increasingly important role in shaping the market value of an organization. At the same time, in the literature it is emphasized that the attribute of intangibility translates into an increased risk of destruction or impairment of assets. Thus, the research problem associated with the analysis of organizational reputation risk management as a component of the dynamic capabilities management process should be considered important from the point of view of management science. The study attempts to outline the concept of dynamic capabilities, define the concept of risk and subsequently discuss the relationship between dynamic capabilities and organizational reputation risk management.

  20. The Influence of Industry Characteristics and Dynamic Capabilities on Firms’ Profitability

    Directory of Open Access Journals (Sweden)

    Maja Pervan

    2017-12-01

    Full Text Available The aim of this research was to explore one of the most intriguing dimensions of every firm’s business—its performance. Aside from analysing the influence of industry’s characteristics on the firm’s performance, the authors addressed the characteristics of dynamic capabilities and their role in contribution to the firm’s ultimate success. The analysis was conducted on a sample of 118 small Croatian manufacturing companies. The application of the Structural Equation Modelling (SEM approach revealed a statistically significant influence of both the industry’s characteristics (represented by Porter’s five forces framework and dynamic capabilities (based on Teece’s theory on the firm’s performance, where the influence of dynamic capabilities is proven to be larger than that of the industry.

  1. Building Dynamic Capabilities in Web Startups: An Empirical Study of Norwegian Web Startups

    OpenAIRE

    Sahlen, Martin Abelson; Gran-Jansen, Sigurd; Rygh, Mathias

    2014-01-01

    Purpose: This thesis explores how web startups operating in a crowded, fast-moving and highly competitive marketplace can gain competitive advantage through building dynamic capabilities and what these capabilities consist of. Design/methodology/approach: Firstly, insight was obtained through reviewing key themes within classic resource based theory and entrepreneurship theory. Newer empirical research on entrepreneurial success factors, as well as popular science and advice given by expert w...

  2. Dynamic Resource Allocation and QoS Control Capabilities of the Japanese Academic Backbone Network

    Directory of Open Access Journals (Sweden)

    Michihiro Aoki

    2010-08-01

    Full Text Available Dynamic resource control capabilities have become increasingly important for academic networks that must support big scientific research projects at the same time as less data intensive research and educational activities. This paper describes the dynamic resource allocation and QoS control capabilities of the Japanese academic backbone network, called SINET3, which supports a variety of academic applications with a wide range of network services. The article describes the network architecture, networking technologies, resource allocation, QoS control, and layer-1 bandwidth on-demand services. It also details typical services developed for scientific research, including the user interface, resource control, and management functions, and includes performance evaluations.

  3. IT-enabled dynamic capability on performance: An empirical study of BSC model

    Directory of Open Access Journals (Sweden)

    Adilson Carlos Yoshikuni

    2017-05-01

    Full Text Available ew studies have investigated the influence of “information capital,” through IT-enabled dynamic capability, on corporate performance, particularly in economic turbulence. Our study investigates the causal relationship between performance perspectives of the balanced scorecard using partial least squares path modeling. Using data on 845 Brazilian companies, we conduct a quantitative empirical study of firms during an economic crisis and observe the following interesting results. Operational and analytical IT-enabled dynamic capability had positive effects on business process improvement and corporate performance. Results pertaining to mediation (endogenous variables and moderation (control variables clarify IT’s role in and benefits for corporate performance.

  4. DYNAMIC CAPABILITIES AND CREATING ORGANIZATIONAL KNOWLEDGE: IMPORTANT LINKAGE FOR BUILDING COMPETITIVE ADVANTAGE

    Directory of Open Access Journals (Sweden)

    Sugiono A.

    2017-08-01

    Full Text Available As a concept derived from the resource-based view, dynamic capabilities essentially have an important linkage with activities related to the creation of organizational knowledge. Using literature study method, this paper aims to discuss the linkage between the creation of dynamic knowledge capabilities and the creation of knowledge company. The study shows that the discussion of dynamic capabilities creation finally puts both learning and knowledge in an important position. Correspondingly, the relationship between a growth strategy that is generally chosen by the organization brings a consequence that the creation of organizational knowledge becomes something that can not be ignored. In order to make the process of knowledge creation in line with dynamic capabilities creation within a growth strategy creation framework, we need a dynamic process of knowledge creation. Among the various models of knowledge creation, SECI model still becomes a relevant model within organizational knowledge creation framework. In general, this study is still theoretical, therefore, more empirical subsequent discussions are expected.

  5. Cross-Sector Partnerships and the Co-creation of Dynamic Capabilities for Stakeholder Orientation

    NARCIS (Netherlands)

    Dentoni, D.; Bitzer, V.C.; Pascucci, S.

    2016-01-01

    This paper explores the relationship between business experience in cross-sector partnerships (CSPs) and the co-creation of what we refer to as ‘dynamic capabilities for stakeholder orientation,’ consisting of the four dimensions of (1) sensing, (2) interacting with, (3) learning from and (4)

  6. Internationalisation of construction business and e-commerce: Innovation, integration and dynamic capabilities

    Directory of Open Access Journals (Sweden)

    Thayaparan Gajendran

    2013-06-01

    Full Text Available Despite the role of internet and web based applications in delivering competitive advantage through e-business process is widely acknowledged, little is done by way of research to use the dynamic capability framework, in exploring the role of ecommerce in the construction business internationalisation. The aim of this paper is to present a literature based theoretical exploration using dynamic capability view to discuss internationalising construction businesses through electronic commerce (e-commerce platforms. This paper contextualises the opportunities for internationalising construction, using a mix of supply chain paradigms, embedded with e-commerce platforms. The paper concludes by identifying the potential of dynamic capabilities of a firm, exploiting the innovation and integration potential of different e-business systems, in contributing to the internationalisation of construction businesses. It proposes that contracting firms with developed dynamic capabilities, has the potential to exploit e-commerce platforms to channel upstream activities to an international destination, and also offers the firm’s products/services to international markets.

  7. Dynamic behavioral fingerprinting': What drives the deployment of environmental information and communication capabilities?

    NARCIS (Netherlands)

    Bremmers, H.J.; Haverkamp, D.J.; Omta, S.W.F.

    2009-01-01

    This article investigates the impact of organizational drivers for the implementation of business process and network information and communication capabilities (ICCs) supporting cleaner production in the Dutch food and beverage industry. We do so with the intention to promote `dynamic behavioral

  8. Training Delivery Methods as Source of Dynamic Capabilities: The Case of Sports' Organisations

    Science.gov (United States)

    Arraya, Marco António Mexia; Porfírio, Jose António

    2017-01-01

    Purpose: Training as an important source of dynamic capabilities (DC) is important to the performance of sports' organisations (SO) both to athletes and to non-athletic staff. There are a variety of training delivery methods (TDMs). The purpose of this study is to determine from a set of six TDMs which one is considered to be the most suitable to…

  9. Statistical Analysis of Zebrafish Locomotor Response.

    Science.gov (United States)

    Liu, Yiwen; Carmer, Robert; Zhang, Gaonan; Venkatraman, Prahatha; Brown, Skye Ashton; Pang, Chi-Pui; Zhang, Mingzhi; Ma, Ping; Leung, Yuk Fai

    2015-01-01

    Zebrafish larvae display rich locomotor behaviour upon external stimulation. The movement can be simultaneously tracked from many larvae arranged in multi-well plates. The resulting time-series locomotor data have been used to reveal new insights into neurobiology and pharmacology. However, the data are of large scale, and the corresponding locomotor behavior is affected by multiple factors. These issues pose a statistical challenge for comparing larval activities. To address this gap, this study has analyzed a visually-driven locomotor behaviour named the visual motor response (VMR) by the Hotelling's T-squared test. This test is congruent with comparing locomotor profiles from a time period. Different wild-type (WT) strains were compared using the test, which shows that they responded differently to light change at different developmental stages. The performance of this test was evaluated by a power analysis, which shows that the test was sensitive for detecting differences between experimental groups with sample numbers that were commonly used in various studies. In addition, this study investigated the effects of various factors that might affect the VMR by multivariate analysis of variance (MANOVA). The results indicate that the larval activity was generally affected by stage, light stimulus, their interaction, and location in the plate. Nonetheless, different factors affected larval activity differently over time, as indicated by a dynamical analysis of the activity at each second. Intriguingly, this analysis also shows that biological and technical repeats had negligible effect on larval activity. This finding is consistent with that from the Hotelling's T-squared test, and suggests that experimental repeats can be combined to enhance statistical power. Together, these investigations have established a statistical framework for analyzing VMR data, a framework that should be generally applicable to other locomotor data with similar structure.

  10. Gait Dynamics and Locomotor Metabolism

    Science.gov (United States)

    2014-12-01

    26 47. Taylor CR, Heglund NC, Maloiy GMO . Energetics and mechanics of terrestrial locomotion. I. Metabolic energy consumption as a function of...San Diego, CA: Academic Press, 1994. 110 47. Taylor CR, Heglund NC, Maloiy GMO . Energetics and mechanics of terrestrial locomotion. I. Metabolic

  11. Does the Size Matter for Dynamics Capabilities? A Study on Absorptive Capacity

    Directory of Open Access Journals (Sweden)

    Marlon Fernandes Rodrigues Alves

    2016-10-01

    Full Text Available The objective of this study is to understand how organizational size influences dynamic capabilities in Brazil. To arrive at this understanding, structural equation modeling analysis was performed using the Brazilian Innovation Survey (PINTEC database to test for differences between SMEs and large companies in respect to the relationship between absorptive capacity (AC dimensions and innovation performance. The results show that in large companies, Potential AC and Realized AC impact innovation performance, whereas in small and medium-sized enterprises (SMEs, only Realized AC has an influence. In addition, SMEs are, in fact, better at converting Realized AC into innovation performance than large companies, probably due to their flexibility and agility. These findings reveal that organizational sizes influence the impact of dynamic capabilities on performance.

  12. Dynamic Analytical Capability to Better Understand and Anticipate Extremist Shifts Within Populations under Authoritarian Regimes.

    Energy Technology Data Exchange (ETDEWEB)

    Bernard, Michael Lewis [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2015-11-01

    The purpose of this work is to create a generalizable data- and theory-supported capability to better understand and anticipate (with quantifiable uncertainty): 1) how the dynamics of allegiance formations between various groups and society are impacted by active conflict and by third-party interventions and 2) how/why extremist allegiances co-evolve over time due to changing geopolitical, sociocultural, and military conditions.

  13. Start-up’s Performance: An Empirical Study on Dynamic Capabilities Under The Contributions of Bricolage and Social Capital

    OpenAIRE

    Huynh, Thanh; Patton, Dean

    2016-01-01

    Objectives: Dynamic capabilities studies have emphasised how firms determine, integrate, build and reconfigure internal and external resources to adapt to rapidly changing business environment (Teece et al., 1997). Dynamic capabilities are described as routines to learn routines, resource integration consists of product development routines and strategic decision making, resource reconfiguration, and resource gain and release which include knowledge creation, alliance and acquisition routines...

  14. Reliability review of the remote tool delivery system locomotor

    Energy Technology Data Exchange (ETDEWEB)

    Chesser, J.B.

    1999-04-01

    The locomotor being built by RedZone Robotics is designed to serve as a remote tool delivery (RID) system for waste retrieval, tank cleaning, viewing, and inspection inside the high-level waste tanks 8D-1 and 8D-2 at West Valley Nuclear Services (WVNS). The RTD systm is to be deployed through a tank riser. The locomotor portion of the RTD system is designed to be inserted into the tank and is to be capable of moving around the tank by supporting itself and moving on the tank internal structural columns. The locomotor will serve as a mounting platform for a dexterous manipulator arm. The complete RTD system consists of the locomotor, dexterous manipulator arm, cameras, lights, cables, hoses, cable/hose management system, power supply, and operator control station.

  15. Applying a multi-replication framework to support dynamic situation assessment and predictive capabilities

    Science.gov (United States)

    Lammers, Craig; McGraw, Robert M.; Steinman, Jeffrey S.

    2005-05-01

    Technological advances and emerging threats reduce the time between target detection and action to an order of a few minutes. To effectively assist with the decision-making process, C4I decision support tools must quickly and dynamically predict and assess alternative Courses Of Action (COAs) to assist Commanders in anticipating potential outcomes. These capabilities can be provided through the faster-than-real-time predictive simulation of plans that are continuously re-calibrating with the real-time picture. This capability allows decision-makers to assess the effects of re-tasking opportunities, providing the decision-maker with tremendous freedom to make time-critical, mid-course decisions. This paper presents an overview and demonstrates the use of a software infrastructure that supports DSAP capabilities. These DSAP capabilities are demonstrated through the use of a Multi-Replication Framework that supports (1) predictivie simulations using JSAF (Joint Semi-Automated Forces); (2) real-time simulation, also using JSAF, as a state estimation mechanism; and, (3) real-time C4I data updates through TBMCS (Theater Battle Management Core Systems). This infrastructure allows multiple replications of a simulation to be executed simultaneously over a grid faster-than-real-time, calibrated with live data feeds. A cost evaluator mechanism analyzes potential outcomes and prunes simulations that diverge from the real-time picture. In particular, this paper primarily serves to walk a user through the process for using the Multi-Replication Framework providing an enhanced decision aid.

  16. Organizational flexibility as a strategic option: fostering dynamic capabilities of hospitals.

    Science.gov (United States)

    Dias, Casimiro; Escoval, Ana

    2014-01-01

    The main purpose of this article is to examine how the internal and external dimensions of organizational flexibility impact hospital performance. Results reveal that matching internal and external flexibilities contributes to the development of capabilities to adopt new strategic options. Such interactions have a significant impact in terms of hospital performance. A cluster of dynamic hospitals, which is characterised by high levels of both internal and external flexibilities, (instead of that have high levels of both internal and external flexibilities) was found to have the double level of performance compared with other clusters. The implications for research and managerial practice are discussed. Copyright © 2014 Longwoods Publishing.

  17. A Dynamic Behaviour Analysis on the Frequency Control Capability of Electric Vehicles

    DEFF Research Database (Denmark)

    Zarogiannis, Athanasios; Marinelli, Mattia; Træholt, Chresten

    2014-01-01

    The paper presents results of a study on the dynamic response of Electric Vehicle’s (EV) when participating in frequency control of an islanded system. The following cases were considered: when there is no EV performing frequency control, when the EV participates in primary frequency control...... and when the EV participates in both primary and secondary frequency control. Different parameters are tested in various combinations, and their influence on frequency deviation as well as power and energy provided by the EV with vehicle-to-grid (V2G) capability is shown....

  18. The Role Of Dynamic Capability In Supporting Transformation And Sustainability Of Permodalan Nasional Madani Ltd

    Directory of Open Access Journals (Sweden)

    Harry Sutanto

    2015-08-01

    Full Text Available This research is motivated by the empirical facts that although the Micro Small Medium Enterprises and despite getting optimal support the Indonesian government in recognition of the significance of its role in supporting the nations economy has experienced stagnation of business growth reflected by lower vertical mobility in the form of small industrial upgrading into secondary industries than medium industrial decline into a small industry. Permodalan Nasional Madani Lt.d the company with a status and legal domicile as a financial state owned enterprise to support Micro Small Medium Enterprises through financing as a financial solution and coaching as a solution of non-financial to form a strong independent and be able to create new jobs.In the period 2009-2013 the company has implemented Transformation First in response to the dynamic changes facing as well as an increase in competence fluctuations in economic conditions and other related matters that put the company in a sharp business complexity. The success of the company carrying out the First Transformation 2009-2013 both in a significant improvement and performance management of the company became the starting point in the implementation of the Second Transformation 2014-2019 and further measures to achieve organization sustainability.The phenomenon of the companys success in implementing the 2009-2013 First Transformation considered highly supported by the formulation and implementation of dynamic capability approach strategy so as to change the paradigm of management of the company from its original direction as financial state owned enterprise with the full support of the government into business-oriented institution to the achievement of sustainable advantage sustainable profit and supported by governance governance good company. This research is in the areas of change management and strategic management more specifically on the development of the concept of dynamic capabilities in

  19. Inward Internationalization of African-Ethnic Restaurants: The Role of Managerial Dynamic Capabilities

    Directory of Open Access Journals (Sweden)

    Samson Omuudu OTENGEI

    2016-12-01

    Full Text Available This paper empirically tests the link between cultural orientation, market orientation, service innovation capabilities of owner-managers and the level of inward internationalisation of African-ethnic restaurants. Data were obtained from 201 African-ethnic restaurants. A twostep approach was used, i.e. (i a confirmatory factor analysis (CFA to generate a measurement model; and (ii a structural equation model (SEM to test the hypotheses. All the predictor variables are positively and significantly related to the degree of inward internationalisation and the relationship is strong enough to cause a 41 per cent variance. Since it is cross-sectional in design, the study cannot be fully relied upon to draw inferences regarding causality among the variables. The results suggest that owner-managers who develop the three capabilities succeed in enhancing inward internationalisation. The current study could be among the very few to propose a framework that brings together major managerial (dynamic capabilities that are presumed to be vital in enhancing inward internationalisation.

  20. A study on the multiple dynamic wavelength distribution for gigabit capable passive optical networks

    Directory of Open Access Journals (Sweden)

    Gustavo Adolfo Puerto Leguizamón

    2014-04-01

    Full Text Available This paper presents a data traffic based study aiming at evaluating the impact of dynamic wavelength allocation on a Gigabit capable Passive Optical Network (GPON. In Passive Optical Networks (PON, an Optical Line Terminal (OLT feeds different PONs in such a way that a given wavelength channel is evenly distributed between the Optical Network Units (ONU at each PON. However, PONs do not specify any kind of dynamic behavior on the way the wavelengths are allocated in the network, a completely static distribution is implemented instead. In thispaper we evaluate the network performance in terms of packet losses and throughput for a number of ONUs being out-of-profile while featuring a given percentage of traffic in excess for a fixed wavelength distribution and for multiple dynamic wavelength allocation. Results show that for a multichannel operation with four wavelengths, the network throughput increases up to a rough value of 19% while the packet losses drop from 22 % to 1.8 % as compared with a static wavelength distribution.

  1. Architecture of firm dynamic capabilities across inter-organizational activities: Explaining innovativeness in the context of nanotechnology

    Science.gov (United States)

    Petricevic, Olga

    In this dissertation I first develop a theoretical framework that explores different components of dynamic capabilities related to firm's boundary-spanning linkages across two different types of inter-organizational activities---alliances and networks. I argue that there are four different subsets of dynamic capabilities simultaneously at work: alliance opportunity-sensing, alliance opportunity-seizing, network opportunity-sensing and network opportunity-seizing. Furthermore, I argue that there are significant interaction effects between these distinctive subsets driving the firm's overall effectiveness in sensing and seizing of novel and innovative external opportunities. In order to explore potential interdependencies and draw distinctions among different dynamic capability subsets I integrate concepts from the two theoretical perspectives that often neglect the emphasis of the other---the dynamic capability view and the social network perspective. I then test the hypothesized relationships in the context of firms actively patenting in nanotechnology. Nanotechnology innovations are multidisciplinary in nature and require search and discovery across multiple inter-organizational, scientific, geographic, industry, or technological domains by a particular firm. The findings offer support for the conceptualizations of dynamic capabilities as consisting of distinct subsets of capabilities for the sensing and the seizing of external new-knowledge opportunities. The findings suggest that firm's innovativeness in an interdisciplinary scientific field such as nanotechnology is the function of the vector of multi-dimensional dynamic capabilities that are context-specific. Furthermore, the findings also suggest that there are inherent trade-offs embedded in different dimensions of dynamic capabilities when deployed across a wide range of inter-organizational relationships.

  2. Improving the forming capability of laser dynamic forming by using rubber as a forming medium

    Science.gov (United States)

    Shen, Zongbao; Liu, Huixia; Wang, Xiao; Wang, Cuntang

    2016-04-01

    Laser dynamic forming (LDF) is a novel high velocity forming technique, which employs laser-generated shock wave to load the sample. The forming velocity induced by the high energy laser pulse may exceed the critical forming velocity, resulting in the occurrence of premature fracture. To avoid the above premature fracture, rubber is introduced in LDF as a forming medium to prolong the loading duration in this paper. Laser induced shock wave energy is transferred to the sample in different forming stages, so the forming velocity can be kept below the critical forming velocity when the initial laser energy is high for fracture. Bulge forming experiments with and without rubber were performed to study the effect of rubber on loading duration. The experimental results show that, the shock wave energy attenuates during the propagation through the rubber layer, the rubber can avoid the premature fracture. So the plastic deformation can continue, the forming capability of LDF is improved. Due to the severe plastic deformation under rubber compression, adiabatic shear bands (ASB) occur in LDF with rubber. The material softening in ASB leads to the irregular fracture, which is different from the premature fracture pattern (regular fracture) in LDF without rubber. To better understand this deformation behavior, Johnson-Cook model is used to simulate the dynamic response and the evolution of ASB of copper sample. The simulation results also indicate the rubber can prolong the loading duration.

  3. Dynamic Positioning Capability Analysis for Marine Vessels Based on A DPCap Polar Plot Program

    Science.gov (United States)

    Wang, Lei; Yang, Jian-min; Xu, Sheng-wen

    2018-03-01

    Dynamic positioning capability (DPCap) analysis is essential in the selection of thrusters, in their configuration, and during preliminary investigation of the positioning ability of a newly designed vessel dynamic positioning system. DPCap analysis can help determine the maximum environmental forces, in which the DP system can counteract in given headings. The accuracy of the DPCap analysis is determined by the precise estimation of the environmental forces as well as the effectiveness of the thrust allocation logic. This paper is dedicated to developing an effective and efficient software program for the DPCap analysis for marine vessels. Estimation of the environmental forces can be obtained by model tests, hydrodynamic computation and empirical formulas. A quadratic programming method is adopted to allocate the total thrust on every thruster of the vessel. A detailed description of the thrust allocation logic of the software program is given. The effectiveness of the new program DPCap Polar Plot (DPCPP) was validated by a DPCap analysis for a supply vessel. The present study indicates that the developed program can be used in the DPCap analysis for marine vessels. Moreover, DPCap analysis considering the thruster failure mode might give guidance to the designers of vessels whose thrusters need to be safer.

  4. Locomotor circumvention strategies are altered by stroke: I. Obstacle clearance.

    Science.gov (United States)

    Darekar, Anuja; Lamontagne, Anouk; Fung, Joyce

    2017-06-15

    Functional locomotion requires the ability to adapt to environmental challenges such as the presence of stationary or moving obstacles. Difficulties in obstacle circumvention often lead to restricted community ambulation in individuals with stroke. The objective of this study was to contrast obstacle circumvention strategies between post-stroke (n = 12) and healthy individuals (n = 12) performing locomotor and perceptuomotor (joystick navigation) tasks with different obstacle approaches. Participants walked and navigated with a joystick towards a central target, in a virtual environment simulating a large room, while avoiding an obstacle that either remained stationary at the pre-determined point of intersection or moved from head-on or diagonally 30° left/right. The outcome measures included dynamic clearance (DC), instantaneous distance from obstacle at crossing (IDC), number of collisions and preferred side of circumvention. These measures were compared between groups (stroke vs. healthy), obstacle parameter (stationary vs. moving head-on) and direction of approach (left/paretic vs. right/non-paretic). DC was significantly larger when circumventing a moving obstacle that approached head-on as compared to a stationary obstacle for both groups during both tasks, while not significantly different in either diagonal approach in either group. IDC was smaller in the stroke group while walking and larger in both groups during joystick navigation when avoiding moving as compared to stationary obstacle. IDC was significantly larger in the stroke group compared to controls for diagonal approaches during walking, wherein two different strategies emerged amongst individuals with stroke: circumventing to the same (V same n = 6) or opposite (V opp n = 4) side of obstacle approach. This behavior was not seen in the perceptuomotor task, wherein post-stroke participants circumvented to opposite side of the obstacle approach as seen in healthy participants. In the

  5. How Overall Logistics Strategy Mediates The Influence Of Market Attractiveness And Dynamic Capability On Strategic Competitive Response

    Directory of Open Access Journals (Sweden)

    Febriyanto

    2015-08-01

    Full Text Available This research is conducted to examine the influence of market attractiveness and dynamic capability on strategic competitive response through overall logistics strategies of logistics service providers LSPs. Involving 266 LSPs SEM-LISREL is applied to test the hypotheses. The findings reveal that the market attractiveness and the dynamic capability positively affect the overall logistics strategy. Additionally the market attractiveness and the dynamic capability positively affect the strategic competitive response. Indirectly the market attractiveness and the dynamic capability positively affect the performance through strategic competitive response of LSPs. Obviously overall logistics strategy strengthen the influence of both market attractiveness and dynamic capability on strategic competitive response. There are five alternatives to optimize the overall logistics strategy of LSPs market intensification integration focus collaboration and strengthening value proposition. The involvement of overall logistics strategy as mediating variable is new paradigm in the strategic management discourses especially in logistics industry. Further research needs to be performed by involving the size of business as control variable and LSPs perception on Governments policies.

  6. Development Of A Dynamic Radiographic Capability Using High-Speed Video

    Science.gov (United States)

    Bryant, Lawrence E.

    1985-02-01

    High-speed video equipment can be used to optically image up to 2,000 full frames per second or 12,000 partial frames per second. X-ray image intensifiers have historically been used to image radiographic images at 30 frames per second. By combining these two types of equipment, it is possible to perform dynamic x-ray imaging of up to 2,000 full frames per second. The technique has been demonstrated using conventional, industrial x-ray sources such as 150 Kv and 300 Kv constant potential x-ray generators, 2.5 MeV Van de Graaffs, and linear accelerators. A crude form of this high-speed radiographic imaging has been shown to be possible with a cobalt 60 source. Use of a maximum aperture lens makes best use of the available light output from the image intensifier. The x-ray image intensifier input and output fluors decay rapidly enough to allow the high frame rate imaging. Data are presented on the maximum possible video frame rates versus x-ray penetration of various thicknesses of aluminum and steel. Photographs illustrate typical radiographic setups using the high speed imaging method. Video recordings show several demonstrations of this technique with the played-back x-ray images slowed down up to 100 times as compared to the actual event speed. Typical applications include boiling type action of liquids in metal containers, compressor operation with visualization of crankshaft, connecting rod and piston movement and thermal battery operation. An interesting aspect of this technique combines both the optical and x-ray capabilities to observe an object or event with both external and internal details with one camera in a visual mode and the other camera in an x-ray mode. This allows both kinds of video images to appear side by side in a synchronized presentation.

  7. Development of a dynamic radiographic capability using high-speed video

    International Nuclear Information System (INIS)

    Bryant, L.E. Jr.

    1984-01-01

    High-speed video equipment can be used to optically image up to 2000 full frames per second or 12,000 partial frames per second. X-ray image intensifiers have historically been used to image radiographic images at 30 frames per second. By combining these two types of equipment, it is possible to perform dynamic x-ray imaging of up to 2,000 full frames per second. The technique has been demonstrated using conventional, industrial x-ray sources such as 150 kV and 300 kV constant potential x-ray generators, 2.5 MeV Van de Graaffs, and linear accelerators. A crude form of this high-speed radiographic imaging has been shown to be possible with a cobalt 60 source. Use of a maximum aperture lens makes best use of the available light output from the image intensifier. The x-ray image intensifier input and output fluors decay rapidly enough to allow the high frame rate imaging. Data are presented on the maximum possible video frame rates versus x-ray penetration of various thicknesses of aluminum and steel. Photographs illustrate typical radiographic setups using the high speed imaging method. Video recordings show several demonstrations of this technique with the played-back x-ray images slowed down up to 100 times as compared to the actual event speed. Typical applications include boiling type action of liquids in metal containers, compressor operation with visualization of crankshaft, connecting rod and piston movement and thermal battery operation. An interesting aspect of this technique combines both the optical and x-ray capabilities to observe an object or event with both external and internal details with one camera in a visual mode and the other camera in an x-ray mode. This allows both kinds of video images to appear side by side in a synchronized presentation

  8. Advanced Simulation Capability for Turbopump Cavitation Dynamics Guided by Experimental Validation, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — Numerical cavitation modeling capability is critical in the design of liquid rocket engine turbopumps, feed lines, injector manifolds and engine test facilities....

  9. Dynamics of vendor innovation capability: Evidence from the Electronics Manufacturing Services industry

    DEFF Research Database (Denmark)

    Perunovic, Zoran; Mefford, Robert; Christoffersen, Mads

    2012-01-01

    and innovation. The first is the realization that vendor capabilities have been recognized as one of the most important factors for the success of outsourcing. The second refers to the fact that, even though innovation capability is required, vendors are still being selected, and their performance evaluated......, by traditional manufacturing capabilities, such as cost, quality, delivery, and flexibility. Taking a vendor’s perspective in outsourcing, we develop and present a conceptual framework for studying vendor innovation capability. We propose to test this framework in the Electronic Manufacturing Services Industry....

  10. Improved fault ride through capability of DFIG based wind turbines using synchronous reference frame control based dynamic voltage restorer.

    Science.gov (United States)

    Rini Ann Jerin, A; Kaliannan, Palanisamy; Subramaniam, Umashankar

    2017-09-01

    Fault ride through (FRT) capability in wind turbines to maintain the grid stability during faults has become mandatory with the increasing grid penetration of wind energy. Doubly fed induction generator based wind turbine (DFIG-WT) is the most popularly utilized type of generator but highly susceptible to the voltage disturbances in grid. Dynamic voltage restorer (DVR) based external FRT capability improvement is considered. Since DVR is capable of providing fast voltage sag mitigation during faults and can maintain the nominal operating conditions for DFIG-WT. The effectiveness of the DVR using Synchronous reference frame (SRF) control is investigated for FRT capability in DFIG-WT during both balanced and unbalanced fault conditions. The operation of DVR is confirmed using time-domain simulation in MATLAB/Simulink using 1.5MW DFIG-WT. Copyright © 2017 ISA. Published by Elsevier Ltd. All rights reserved.

  11. Dual spinal lesion paradigm in the cat: evolution of the kinematic locomotor pattern.

    Science.gov (United States)

    Barrière, Grégory; Frigon, Alain; Leblond, Hugues; Provencher, Janyne; Rossignol, Serge

    2010-08-01

    The recovery of voluntary quadrupedal locomotion after an incomplete spinal cord injury can involve different levels of the CNS, including the spinal locomotor circuitry. The latter conclusion was reached using a dual spinal lesion paradigm in which a low thoracic partial spinal lesion is followed, several weeks later, by a complete spinal transection (i.e., spinalization). In this dual spinal lesion paradigm, cats can express hindlimb walking 1 day after spinalization, a process that normally takes several weeks, suggesting that the locomotor circuitry within the lumbosacral spinal cord had been modified after the partial lesion. Here we detail the evolution of the kinematic locomotor pattern throughout the dual spinal lesion paradigm in five cats to gain further insight into putative neurophysiological mechanisms involved in locomotor recovery after a partial spinal lesion. All cats recovered voluntary quadrupedal locomotion with treadmill training (3-5 days/wk) over several weeks. After the partial lesion, the locomotor pattern was characterized by several left/right asymmetries in various kinematic parameters, such as homolateral and homologous interlimb coupling, cycle duration, and swing/stance durations. When no further locomotor improvement was observed, cats were spinalized. After spinalization, the hindlimb locomotor pattern rapidly reappeared, but left/right asymmetries in swing/stance durations observed after the partial lesion could disappear or reverse. It is concluded that, after a partial spinal lesion, the hindlimb locomotor pattern was actively maintained by new dynamic interactions between spinal and supraspinal levels but also by intrinsic changes within the spinal cord.

  12. Gossiping Capabilities

    DEFF Research Database (Denmark)

    Mogensen, Martin; Frey, Davide; Guerraoui, Rachid

    Gossip-based protocols are now acknowledged as a sound basis to implement collaborative high-bandwidth content dissemination: content location is disseminated through gossip, the actual contents being subsequently pulled. In this paper, we present HEAP, HEterogeneity Aware gossip Protocol, where...... nodes dynamically adjust their contribution to gossip dissemination according to their capabilities. Using a continuous, itself gossip-based, approximation of relative capabilities, HEAP dynamically leverages the most capable nodes by (a) increasing their fanouts (while decreasing by the same proportion...... declare a high capability in order to augment their perceived quality without contributing accordingly. We evaluate HEAP in the context of a video streaming application on a 236 PlanetLab nodes testbed. Our results shows that HEAP improves the quality of the streaming by 25% over a standard gossip...

  13. The Application of Dynamic Capabilities in E-commerce Innovation Context : The Implications for Chinese E-commerce companies

    OpenAIRE

    Chen, YongJia; Liang, WeiMin

    2007-01-01

    This study mainly investigated how Chinese E-commerce companies should cope with E-commerce innovation with specific dynamic capabilities. E-commerce (Electronic Commerce) innovation includes three phases of innovation based on technology and time. They are web-based commerce, mobile commerce (M-commerce) and ubiquitous commerce (U-commerce). They caused not only technological changes but also organizational changes. To cope with E-commerce innovation, a prerequisite is to understand the impa...

  14. The influence of company’s dynamic capabilities on achieving a competitive advantage as the new management paradigm

    Directory of Open Access Journals (Sweden)

    Ilona Penc-Pietrzak

    2014-12-01

    Full Text Available The paper presents the most important conceptions of achieving a company’s competitive advantage: Porter’s five forces model based on the SCP paradigm; the conception of strategic conflict, which uses the tools of game theory; resource-based perspective, which emphasizes the distinctive resources and skills of a company and the dynamic capabilities approach, which is very useful in turbulent environment. The last conception is correctly treated as the new management paradigm.

  15. Extending the Capabilities of the Mooring Analysis Program: A Survey of Dynamic Mooring Line Theories for Integration into FAST: Preprint

    Energy Technology Data Exchange (ETDEWEB)

    Masciola, M.; Jonkman, J.; Robertson, A.

    2014-03-01

    Techniques to model dynamic mooring lines come in various forms. The most widely used models include either a heuristic representation of the physics (such as a Lumped-Mass, LM, system), a Finite-Element Analysis (FEA) discretization of the lines (discretized in space), or a Finite-Difference (FD) model (which is discretized in both space and time). In this paper, we explore the features of the various models, weigh the advantages of each, and propose a plan for implementing one dynamic mooring line model into the open-source Mooring Analysis Program (MAP). MAP is currently used as a module for the FAST offshore wind turbine computer-aided engineering (CAE) tool to model mooring systems quasi-statically, although dynamic mooring capabilities are desired. Based on the exploration in this manuscript, the lumped-mass representation is selected for implementation in MAP based on its simplicity, computational cost, and ability to provide similar physics captured by higher-order models.

  16. Organizational capabilities assessment: a dynamic methodology, methods and a tool for supporting organizational diagnosis

    OpenAIRE

    Rauffet , Philippe; Da Cunha , Catherine ,; Bernard , Alain

    2010-01-01

    Many methods, like CMMI, ISO norms or 5 steps roadmapping, are implemented in organizations in order to develop collective competencies, called also organizational capabilities, around organizational needs. They aim at providing new means to controls resources of organization, and enabling an organizational diagnosis, it is to say the evaluation of the strengths and the weaknesses of the organization. Nevertheless, these methods are generally based on knowledge based models (they are composed...

  17. Predictive Measures of Locomotor Performance on an Unstable Walking Surface

    Science.gov (United States)

    Bloomberg, J. J.; Peters, B. T.; Mulavara, A. P.; Caldwell, E. E.; Batson, C. D.; De Dios, Y. E.; Gadd, N. E.; Goel, R.; Wood, S. J.; Cohen, H. S.; hide

    2016-01-01

    Locomotion requires integration of visual, vestibular, and somatosensory information to produce the appropriate motor output to control movement. The degree to which these sensory inputs are weighted and reorganized in discordant sensory environments varies by individual and may be predictive of the ability to adapt to novel environments. The goals of this project are to: 1) develop a set of predictive measures capable of identifying individual differences in sensorimotor adaptability, and 2) use this information to inform the design of training countermeasures designed to enhance the ability of astronauts to adapt to gravitational transitions improving balance and locomotor performance after a Mars landing and enhancing egress capability after a landing on Earth.

  18. Error signals driving locomotor adaptation

    DEFF Research Database (Denmark)

    Choi, Julia T; Jensen, Peter; Nielsen, Jens Bo

    2016-01-01

    Locomotor patterns must be adapted to external forces encountered during daily activities. The contribution of different sensory inputs to detecting perturbations and adapting movements during walking is unclear. Here we examined the role of cutaneous feedback in adapting walking patterns to force...... walking (Choi et al. 2013). Sensory tests were performed to measure cutaneous touch threshold and perceptual threshold of force perturbations. Ankle movement were measured while subjects walked on the treadmill over three periods: baseline (1 min), adaptation (1 min) and post-adaptation (3 min). Subjects...

  19. THE ANTECEDENTS OF ORGANIZATIONAL AGILITY: ORGANIZATIONAL STRUCTURE, DYNAMIC CAPABILITIES AND CUSTOMER ORIENTATION

    OpenAIRE

    Kanten, Pelin; Kanten, Selahattin; Keceli, Munevver; Zaimoglu, Zuhal

    2017-01-01

    This study aims to investigate someantecedents of organizational agility. In the literature, it is seen thatstudies suggest that some organizational factors provide to maintainorganizational agility. Therefore, organizational structure, dynamic capabilitiesand customer orientation are considered as predictors of organizational agilitywithin the scope of the study. For this purpose, the data which were collectedfrom 176 employees in the retailing industry by the survey method were analyzedusin...

  20. A dynamic capabilities perspective on service-orientation in demand-supply chains

    NARCIS (Netherlands)

    Rasouli, M.; Trienekens, J.J.M.; Kusters, R.J.; Grefen, P.W.P.J.; Shpitalni, M.; Fisher, A.; Molcho, I.

    2015-01-01

    Organizations in the current competitive business environment need to provide highly customized integrated solutions through dynamic collaborations within value networks. This need has been increasingly considered through different notions like Product Service System (PSS) and Service-Dominant (S-D)

  1. Entry into new markets: the development of the business model and dynamic capabilities

    Directory of Open Access Journals (Sweden)

    Victor Wolowski Kenski

    2017-12-01

    Full Text Available This work shows the path through which companies enter new markets or bring new propositions to established ones. It presents the market analysis process, the strategical decisions that determine the company’s position on it and the required changes in the configurations for this new action. It also studies the process of selecting the business model and the conditions for its definition the adoption and subsequent development of resources and capabilities required to conquer this new market. It is presented the necessary conditions to remain and maintain its market position. These concepts are presented through a case study of a business group that takes part in different franchises.

  2. MicroRNA dynamics in the stages of tumorigenesis correlate with hallmark capabilities of cancer.

    Science.gov (United States)

    Olson, Peter; Lu, Jun; Zhang, Hao; Shai, Anny; Chun, Matthew G; Wang, Yucheng; Libutti, Steven K; Nakakura, Eric K; Golub, Todd R; Hanahan, Douglas

    2009-09-15

    While altered expression of microRNAs (miRs) in tumors has been well documented, it remains unclear how the miR transcriptome intersects neoplastic progression. By profiling the miR transcriptome we identified miR expression signatures associated with steps in tumorigenesis and the acquisition of hallmark capabilities in a prototypical mouse model of cancer. Metastases and a rare subset of primary tumors shared a distinct miR signature, implicating a discrete lineage for metastatic tumors. The miR-200 family is strongly down-regulated in metastases and met-like primary tumors, thereby relieving repression of the mesenchymal transcription factor Zeb1, which in turn suppresses E-cadherin. Treatment with a clinically approved angiogenesis inhibitor normalized angiogenic signature miRs in primary tumors, while altering expression of metastatic signature miRs similarly to liver metastases, suggesting their involvement in adaptive resistance to anti-angiogenic therapy via enhanced metastasis. Many of the miR changes associated with specific stages and hallmark capabilities in the mouse model are similarly altered in human tumors, including cognate pancreatic neuroendocrine tumors, implying a generality.

  3. Capabilities for Strategic Adaptation

    DEFF Research Database (Denmark)

    Distel, Andreas Philipp

    This dissertation explores capabilities that enable firms to strategically adapt to environmental changes and preserve competitiveness over time – often referred to as dynamic capabilities. While dynamic capabilities being a popular research domain, too little is known about what these capabiliti...

  4. Exploring the impact of dynamic capabilities on sustainable supply chain firm's performance using Grey-Analytical Hierarchy Process

    DEFF Research Database (Denmark)

    Govindan, Kannan; Mathivathanan, Deepak; Haq, A. Noorul

    2017-01-01

    Dynamic capabilities (DCs) are the inherent capabilities developed by firms through the implementation of Sustainable Supply Chain practices. These DCs serve as a backbone for the firms to achieve competitive advantages in contemporary ever-changing markets. The present study focuses on exploring...... industrial managers to identify specific influential DCs for each performance measure category by overcoming the limitations of few experts through the application of the grey multi criteria decision making system. Identifying and prioritizing performance-specific DCs allow sustainable supply chain oriented...... performance measures identified from the literature. First, through a questionnaire survey with industrial experts from south India as respondents, the initial list of 77 DCs is confined to a list of 40 essential DCs. Second, the shortlisted 40 DCs are grouped under six performance measures; a logical...

  5. Understanding and Supporting Dynamic Capabilities of Design Teams in Production of Technology-Innovation

    DEFF Research Database (Denmark)

    Jensen, Ole Kjeldal

    Rapid adaptation to a changing environment is essential for the survival of incumbent companies, but the capabilities required to lead the disruption of a technological trajectory are generally challenged by the process management activities that make the company operate efficiently within its...... current environment. This study explores the practices of engineering designers that are executing disruptive innovation projects for DONG Energy, a Danish energy utilities company. The aim of the study was to understand the role of the designer in disruptive innovation and to create a tool for supporting...... multidisciplinary design teams, while creating disruptive innovations. The results from this study are presented in five research Papers that address the following themes: 1) the willingness of engineers to follow formal procedures, 2) critical knowledge domains in front-end technology decisions, 3) knowledge...

  6. Conditional repair by locally switching the thermal healing capability of dynamic covalent polymers with light

    Science.gov (United States)

    Fuhrmann, Anne; Göstl, Robert; Wendt, Robert; Kötteritzsch, Julia; Hager, Martin D.; Schubert, Ulrich S.; Brademann-Jock, Kerstin; Thünemann, Andreas F.; Nöchel, Ulrich; Behl, Marc; Hecht, Stefan

    2016-12-01

    Healable materials could play an important role in reducing the environmental footprint of our modern technological society through extending the life cycles of consumer products and constructions. However, as most healing processes are carried out by heat alone, the ability to heal damage generally kills the parent material's thermal and mechanical properties. Here we present a dynamic covalent polymer network whose thermal healing ability can be switched `on' and `off' on demand by light, thereby providing local control over repair while retaining the advantageous macroscopic properties of static polymer networks. We employ a photoswitchable furan-based crosslinker, which reacts with short and mobile maleimide-substituted poly(lauryl methacrylate) chains forming strong covalent bonds while simultaneously allowing the reversible, spatiotemporally resolved control over thermally induced de- and re-crosslinking. We reason that our system can be adapted to more complex materials and has the potential to impact applications in responsive coatings, photolithography and microfabrication.

  7. NEW GROWTH PLATFORM FRAMEWORK FOR SWISS ACUTE HOSPITALS - AN EMPIRICAL STUDY FOR THE DEVELOPMENT OF DYNAMIC CAPABILITIES

    Directory of Open Access Journals (Sweden)

    Zoran Alimpic

    2013-11-01

    Full Text Available Swiss health care is confronted with fundamental changes. On the one hand, there are increasing costs in patient treatments, caused by innovative technology with new high-capacity medical devices, and a lack of effectiveness and efficiency in the organisation of a hospital. On the other hand, hospitals do have decreasing revenues with the introduction of the new patient classification and tariff system DRG (Diagnosis Related Groups by 2012. For every DRG, hospitals will receive a fixed price, separate from the actual costs of the patient treatment. In this paper it was explored the case of 13 successful Swiss private acute hospitals which are also confronted with these pressures to reduce their costs of patient treatment and therefore to optimise their processes of care. This research focuses on dynamic capabilitie of the hospitals. Although dynamic capabilities are idiosyncratic in their details and path dependent in their emergence, they have significant ‘best practise’ across firms (Eisenhardt and Martin, 2000. The research is started with the evaluation of new trends, key customers’ needs, and capabilities, with questionnaires for attending physicians and hospital managers. The NGP approach gives hospital managers the enough crucial information for a strategy formulation in fundamental changing environments, which is the key contribution of this manuscript.

  8. Analysis of stationary fuel cell dynamic ramping capabilities and ultra capacitor energy storage using high resolution demand data

    Science.gov (United States)

    Meacham, James R.; Jabbari, Faryar; Brouwer, Jacob; Mauzey, Josh L.; Samuelsen, G. Scott

    Current high temperature fuel cell (HTFC) systems used for stationary power applications (in the 200-300 kW size range) have very limited dynamic load following capability or are simply base load devices. Considering the economics of existing electric utility rate structures, there is little incentive to increase HTFC ramping capability beyond 1 kWs -1 (0.4% s -1). However, in order to ease concerns about grid instabilities from utility companies and increase market adoption, HTFC systems will have to increase their ramping abilities, and will likely have to incorporate electrical energy storage (EES). Because batteries have low power densities and limited lifetimes in highly cyclic applications, ultra capacitors may be the EES medium of choice. The current analyses show that, because ultra capacitors have a very low energy storage density, their integration with HTFC systems may not be feasible unless the fuel cell has a ramp rate approaching 10 kWs -1 (4% s -1) when using a worst-case design analysis. This requirement for fast dynamic load response characteristics can be reduced to 1 kWs -1 by utilizing high resolution demand data to properly size ultra capacitor systems and through demand management techniques that reduce load volatility.

  9. STEREO WAVES Capabilities for Studying Initiation and Early-time Dynamics of Solar Eruptions

    Science.gov (United States)

    Kaiser, M. L.

    2005-01-01

    In 2006, NASA will launch the twin STEREO spacecraft from Kennedy Space Center into a pair of heliocentric orbits near 1 AU such that the spacecraft will move away from Earth (ahead and behind) at about 22 degrees per year. The purposes of the STEREO Mission are to understand the causes and mechanisms of coronal mass ejection (CME) initiation and to follow the propagation of CMEs through the heliosphere. Additionally, STEREO will study the mechanisms and sites of solar energetic particle (SEP) acceleration and determine 3-D time-dependent traces of the magnetic topology, temperature, density and velocity of the solar wind between the sun and Earth. To accomplish these goals, each STEREO spacecraft will be equipped with set of optical and particles and fields instruments including the STEREO WAVES (SWAVES) instrument which will use radio waves to track the location of CME-driven shocks (via type I1 bursts) and the 3-D topology of open field lines along which energetic particles flow (via the ubiquitous type I11 bursts). Type 11 bursts very often commence with a series of special type 111 bursts (called SA or type 111-L bursts) that likely coincide with CME liftoff time, thus SWAVES should be able to determine this time to within 15 sec. It is also known that the occurrence of SEP events is usually accompanied by type I1 radio bursts at decametric wavelengths as well as strong type III bursts at all wavelengths. SWAVES will be able to determine the initiation of these bursts to within 15 sec, and from the simultaneous measurements from the two spacecraft, should be able to triangulate their source locations. The utility of radio observations and the capabilities of SWAVES will be illustrated by showing a number of examples using the similar Wind WAVES instrument in combination with SOH0 coronagraph and RHESSI high energy X-ray/gamma ray observations.

  10. Locomotor adaptation to a soleus EMG-controlled antagonistic exoskeleton

    Science.gov (United States)

    Kinnaird, Catherine R.; Ferris, Daniel P.

    2013-01-01

    Locomotor adaptation in humans is not well understood. To provide insight into the neural reorganization that occurs following a significant disruption to one's learned neuromuscular map relating a given motor command to its resulting muscular action, we tied the mechanical action of a robotic exoskeleton to the electromyography (EMG) profile of the soleus muscle during walking. The powered exoskeleton produced an ankle dorsiflexion torque proportional to soleus muscle recruitment thus limiting the soleus' plantar flexion torque capability. We hypothesized that neurologically intact subjects would alter muscle activation patterns in response to the antagonistic exoskeleton by decreasing soleus recruitment. Subjects practiced walking with the exoskeleton for two 30-min sessions. The initial response to the perturbation was to “fight” the resistive exoskeleton by increasing soleus activation. By the end of training, subjects had significantly reduced soleus recruitment resulting in a gait pattern with almost no ankle push-off. In addition, there was a trend for subjects to reduce gastrocnemius recruitment in proportion to the soleus even though only the soleus EMG was used to control the exoskeleton. The results from this study demonstrate the ability of the nervous system to recalibrate locomotor output in response to substantial changes in the mechanical output of the soleus muscle and associated sensory feedback. This study provides further evidence that the human locomotor system of intact individuals is highly flexible and able to adapt to achieve effective locomotion in response to a broad range of neuromuscular perturbations. PMID:23307949

  11. Locomotor adaptation to a soleus EMG-controlled antagonistic exoskeleton.

    Science.gov (United States)

    Gordon, Keith E; Kinnaird, Catherine R; Ferris, Daniel P

    2013-04-01

    Locomotor adaptation in humans is not well understood. To provide insight into the neural reorganization that occurs following a significant disruption to one's learned neuromuscular map relating a given motor command to its resulting muscular action, we tied the mechanical action of a robotic exoskeleton to the electromyography (EMG) profile of the soleus muscle during walking. The powered exoskeleton produced an ankle dorsiflexion torque proportional to soleus muscle recruitment thus limiting the soleus' plantar flexion torque capability. We hypothesized that neurologically intact subjects would alter muscle activation patterns in response to the antagonistic exoskeleton by decreasing soleus recruitment. Subjects practiced walking with the exoskeleton for two 30-min sessions. The initial response to the perturbation was to "fight" the resistive exoskeleton by increasing soleus activation. By the end of training, subjects had significantly reduced soleus recruitment resulting in a gait pattern with almost no ankle push-off. In addition, there was a trend for subjects to reduce gastrocnemius recruitment in proportion to the soleus even though only the soleus EMG was used to control the exoskeleton. The results from this study demonstrate the ability of the nervous system to recalibrate locomotor output in response to substantial changes in the mechanical output of the soleus muscle and associated sensory feedback. This study provides further evidence that the human locomotor system of intact individuals is highly flexible and able to adapt to achieve effective locomotion in response to a broad range of neuromuscular perturbations.

  12. Comparison of capability of dynamic O2-enhanced MRI and quantitative thin-section MDCT to assess COPD in smokers

    International Nuclear Information System (INIS)

    Ohno, Yoshiharu; Koyama, Hisanobu; Yoshikawa, Takeshi; Matsumoto, Keiko; Aoyama, Nobukazu; Onishi, Yumiko; Takenaka, Daisuke; Matsumoto, Sumiaki; Nishimura, Yoshihiro; Sugimura, Kazuro

    2012-01-01

    Purpose: The purpose of this study was to directly and prospectively compare the capability of dynamic O 2 -enhanced MRI and quantitatively assessed thin-section MDCT to assess smokers’ COPD in a large prospective cohort. Materials and methods: The GOLD criteria for smokers were used to classify 187 smokers into four clinical stage groups as follows: smokers without COPD (n = 56) and with mild (n = 54), moderate (n = 52) and severe or very severe COPD (n = 24). All smokers underwent dynamic O 2 -enhanced MRI, MDCT and pulmonary function tests. Mean relative enhancement ratio and mean wash-in time on MRI and CT-based functional lung volume (CT-based FLV) as well as the ratio of airway wall area to total airway area on MDCT were computationally calculated. Then, all indexes were significantly correlated with functional parameters. To determine the efficacy of all indexes for clinical stage classification, the indexes for the four clinical groups were statistically compared by using Tukey's honestly significant difference multiple comparison test. Results: All indexes had significant correlations with functional parameters (p 2 -enhanced MRI for assessment of COPD in smokers is potentially as efficacious as quantitatively assessed thin-section MDCT.

  13. The Strategic Fitness Process: A Collaborative Action Research Method for Developing and Understanding Organizational Prototypes and Dynamic Capabilities

    Directory of Open Access Journals (Sweden)

    Michael Beer

    2013-04-01

    Full Text Available Organizations underperform and sometimes fail because their leaders are unable to learn the unvarnished truth from relevant stakeholders about how the design and behavior of the organization is misaligned with its goals and strategy. The Strategic Fitness Process (SFP was designed to enable leaders to overcome organizational silence about the misalignment with the environment and chosen strategy. By enabling an honest, organization-wide and public conversation, senior management teams, working collaboratively with scholar-consultants and organizational members, have access to valid data (the unvarnished truth, can conduct a valid diagnosis, and can develop a valid plan to change the structure, processes, and behavior of an organization while at the same time developing commitment that ensures execution. SFP is also a research method. By applying SFP iteratively to new and challenging situations, scholar-consultants can invent new organizational prototypes as well as learn if a standardized and institutionalized organizational learning process like SFP can enhance dynamic capabilities. The SFP model is illustrated with an application to Hewlett-Packard’s Santa Rosa Systems Division.

  14. Disruption of locomotor adaptation with repetitive transcranial magnetic stimulation over the motor cortex

    DEFF Research Database (Denmark)

    Choi, Julia Tsok Lam; Bouyer, Laurent J; Nielsen, Jens Bo

    2015-01-01

    Locomotor patterns are adapted on a trial-and-error basis to account for predictable dynamics. Once a walking pattern is adapted, the new calibration is stored and must be actively de-adapted. Here, we tested the hypothesis that storage of newly acquired ankle adaptation in walking is dependent...

  15. Fractional-Order Information in the Visual Control of Lateral Locomotor Interception

    NARCIS (Netherlands)

    Bootsma, Reinoud J.; Ledouit, Simon; Casanova, Remy; Zaal, Frank T. J. M.

    Previous work on locomotor interception of a target moving in the transverse plane has suggested that interception is achieved by maintaining the target's bearing angle (often inadvertently confused and/or confounded with the target heading angle) at a constant value. However, dynamics-based model

  16. NASA Langley's AirSTAR Testbed: A Subscale Flight Test Capability for Flight Dynamics and Control System Experiments

    Science.gov (United States)

    Jordan, Thomas L.; Bailey, Roger M.

    2008-01-01

    As part of the Airborne Subscale Transport Aircraft Research (AirSTAR) project, NASA Langley Research Center (LaRC) has developed a subscaled flying testbed in order to conduct research experiments in support of the goals of NASA s Aviation Safety Program. This research capability consists of three distinct components. The first of these is the research aircraft, of which there are several in the AirSTAR stable. These aircraft range from a dynamically-scaled, twin turbine vehicle to a propeller driven, off-the-shelf airframe. Each of these airframes carves out its own niche in the research test program. All of the airplanes have sophisticated on-board data acquisition and actuation systems, recording, telemetering, processing, and/or receiving data from research control systems. The second piece of the testbed is the ground facilities, which encompass the hardware and software infrastructure necessary to provide comprehensive support services for conducting flight research using the subscale aircraft, including: subsystem development, integrated testing, remote piloting of the subscale aircraft, telemetry processing, experimental flight control law implementation and evaluation, flight simulation, data recording/archiving, and communications. The ground facilities are comprised of two major components: (1) The Base Research Station (BRS), a LaRC laboratory facility for system development, testing and data analysis, and (2) The Mobile Operations Station (MOS), a self-contained, motorized vehicle serving as a mobile research command/operations center, functionally equivalent to the BRS, capable of deployment to remote sites for supporting flight tests. The third piece of the testbed is the test facility itself. Research flights carried out by the AirSTAR team are conducted at NASA Wallops Flight Facility (WFF) on the Eastern Shore of Virginia. The UAV Island runway is a 50 x 1500 paved runway that lies within restricted airspace at Wallops Flight Facility. The

  17. Footwear and locomotor skill performance in preschoolers.

    Science.gov (United States)

    Robinson, Leah E; Rudisill, Mary E; Weimar, Wendi H; Breslin, Casey M; Shroyer, Justin F; Morera, Maria

    2011-10-01

    The effect of footwear on locomotor skill performance was examined. 12 children (4 boys, 8 girls; M age = 56.3 mo., SD = 3.3) served as participants. Participants were randomly assigned to perform the locomotor subscale of Ulrich's Test of Gross Motor Development in two shoe conditions (Condition 1: Stride Rite athletic shoes, and Condition 2: flip flop sandals). Children scored significantly higher when wearing athletic shoes than flip-flop sandals. This finding is relevant for motor performance and safety in physical education and movement programs.

  18. Capability Paternalism

    NARCIS (Netherlands)

    Claassen, R.J.G.|info:eu-repo/dai/nl/269266224

    A capability approach prescribes paternalist government actions to the extent that it requires the promotion of specific functionings, instead of the corresponding capabilities. Capability theorists have argued that their theories do not have much of these paternalist implications, since promoting

  19. Impact of Organizational Inertia and Dynamic Capabilities on Educational Performance of the Charitable Societies and Its Impact on Mathematical Performance of Elementary At-Risk Students

    Science.gov (United States)

    Amiripour, Parvaneh; Dossey, John A.; Shahvarani, Ahmad

    2017-01-01

    This study is an adjunct to a research effort focused on a mathematical curricular innovation in four non-governmental schools in Tehran, Iran. This study queried balanced, random sample of 100 educational personnel from the schools concerning dynamic capabilities associated with change (sensing opportunities, seizing opportunities, and…

  20. Altered Patterns of Reflex Excitability, Balance, and Locomotion Following Spinal Cord Injury (SCI and Locomotor Training.

    Directory of Open Access Journals (Sweden)

    Prodip K Bose

    2012-07-01

    Full Text Available Spasticity is an important problem that complicates daily living in many individuals with SCI. While previous studies in human and animals revealed significant improvements in locomotor ability with treadmill locomotor training, it is not known to what extent locomotor training influences spasticity. In addition, it would be of considerable practical interest to know how the more ergonomically feasible cycle training compares with treadmill training as therapy to manage SCI-induced spasticity and to improve locomotor function. Our present studies were initiated to evaluate the influence of different types of locomotor training on measures of limb spasticity, gait, and reflex components that contribute to locomotion. For these studies, thirty animals received midthoracic SCI using the standard MASCIS protocol (10 g 2.5 cm weight drop. They were divided randomly into three equal groups: control (contused untrained, contused treadmill trained, and contused cycle trained. Velocity-dependent ankle torque was tested across a wide range of velocities (612 – 49 deg/sec to permit quantitation of tonic (low velocity and dynamic (high velocity contributions to lower limb spasticity. Treadmill and cycle training were started on post-injury day 8. By post-injury weeks 4 and 6, the untrained group revealed significant velocity-dependent ankle extensor spasticity, compared to pre-surgical control values. At these post-injury time points, spasticity was not observed in either of the two training groups. Instead, a significantly milder form of velocity dependent spasticity was detected at postcontusion week 8 through 12 in both treadmill and bicycle training groups at the four fastest ankle rotation velocities (350 - 612 deg/sec. Locomotor training using treadmill or bicycle also produced significant increase in the rate of recovery of limb placement measures (limb axis, base of support, and BBB and reflex rate depression, a quantitative assessment of

  1. Neuromodulation of the lumbar spinal locomotor circuit.

    Science.gov (United States)

    AuYong, Nicholas; Lu, Daniel C

    2014-01-01

    The lumbar spinal cord contains the necessary circuitry to independently drive locomotor behaviors. This function is retained following spinal cord injury (SCI) and is amenable to rehabilitation. Although the effectiveness of task-specific training and pharmacologic modulation has been repeatedly demonstrated in animal studies, results from human studies are less striking. Recently, lumbar epidural stimulation (EDS) along with locomotor training was shown to restore weight-bearing function and lower-extremity voluntary control in a chronic, motor-complete human SCI subject. Related animal studies incorporating EDS as part of the therapeutic regiment are also encouraging. EDS is emerging as a promising neuromodulatory tool for SCI. Copyright © 2014 Elsevier Inc. All rights reserved.

  2. Dynamic Capabilities Associated with a Firm’s Growth in Developing Countries. A Comparative Study of Argentinean SMEs in the Software and Tourism Industries

    Directory of Open Access Journals (Sweden)

    Claudia D’Annunzio

    2015-01-01

    Full Text Available Although recent evidence suggests that the development of dynamic capabilities (DC is a key factor to gain and sustain competitive advantages to promote firm ́s growth, the question of how SMEs create, identify, and seize opportunities for growth have not been fully explored, particularly in developing countries with scarce resources. The aim of this study is to shed light on how SMEs develop capabilities to grow in the specific context of developing countries with resources constraints. To achieve a detailed description of the processes involved, this study applies a qualitative methodology based on a comparative case study of eight SMEs within the software and tourism industries in Argentine, which have been previously identified as dynamic sectors with high growth potential. Our findings suggest that SMEs develop DC mainly through an emerging process of iterative experimentation rather than through strategic planning. This process involves the coordination of organizational actions and resources, with managers playing a key role.

  3. Dopamine and the Brainstem Locomotor Networks: From Lamprey to Human

    Directory of Open Access Journals (Sweden)

    Dimitri Ryczko

    2017-05-01

    Full Text Available In vertebrates, dopamine neurons are classically known to modulate locomotion via their ascending projections to the basal ganglia that project to brainstem locomotor networks. An increased dopaminergic tone is associated with increase in locomotor activity. In pathological conditions where dopamine cells are lost, such as in Parkinson's disease, locomotor deficits are traditionally associated with the reduced ascending dopaminergic input to the basal ganglia. However, a descending dopaminergic pathway originating from the substantia nigra pars compacta was recently discovered. It innervates the mesencephalic locomotor region (MLR from basal vertebrates to mammals. This pathway was shown to increase locomotor output in lampreys, and could very well play an important role in mammals. Here, we provide a detailed account on the newly found dopaminergic pathway in lamprey, salamander, rat, monkey, and human. In lampreys and salamanders, dopamine release in the MLR is associated with the activation of reticulospinal neurons that carry the locomotor command to the spinal cord. Dopamine release in the MLR potentiates locomotor movements through a D1-receptor mechanism in lampreys. In rats, stimulation of the substantia nigra pars compacta elicited dopamine release in the pedunculopontine nucleus, a known part of the MLR. In a monkey model of Parkinson's disease, a reduced dopaminergic innervation of the brainstem locomotor networks was reported. Dopaminergic fibers are also present in human pedunculopontine nucleus. We discuss the conserved locomotor role of this pathway from lamprey to mammals, and the hypothesis that this pathway could play a role in the locomotor deficits reported in Parkinson's disease.

  4. Denitrifying capability and community dynamics of glycogen accumulating organisms during sludge granulation in an anaerobic-aerobic sequencing batch reactor

    Science.gov (United States)

    Bin, Zhang; Bin, Xue; Zhigang, Qiu; Zhiqiang, Chen; Junwen, Li; Taishi, Gong; Wenci, Zou; Jingfeng, Wang

    2015-08-01

    Denitrifying capability of glycogen accumulating organisms (GAOs) has received great attention in environmental science and microbial ecology. Combining this ability with granule processes would be an interesting attempt. Here, a laboratory-scale sequencing batch reactor (SBR) was operated to enrich GAOs and enable sludge granulation. The results showed that the GAO granules were cultivated successfully and the granules had denitrifying capability. The batch experiments demonstrated that all NO3--N could be removed or reduced, some amount of NO2--N were accumulated in the reactor, and N2 was the main gaseous product. SEM analysis suggested that the granules were tightly packed with a large amount of tetrad-forming organisms (TFOs); filamentous bacteria served as the supporting structures for the granules. The microbial community structure of GAO granules was differed substantially from the inoculant conventional activated sludge. Most of the bacteria in the seed sludge grouped with members of Proteobacterium. FISH analysis confirmed that GAOs were the predominant members in the granules and were distributed evenly throughout the granular space. In contrast, PAOs were severely inhibited. Overall, cultivation of the GAO granules and utilizing their denitrifying capability can provide us with a new approach of nitrogen removal and saving more energy.

  5. Capability ethics

    OpenAIRE

    Robeyns, Ingrid

    2012-01-01

    textabstractThe capability approach is one of the most recent additions to the landscape of normative theories in ethics and political philosophy. Yet in its present stage of development, the capability approach is not a full-blown normative theory, in contrast to utilitarianism, deontological theories, virtue ethics, or pragmatism. As I will argue in this chapter, at present the core of the capability approach is an account of value, which together with some other (more minor) normative comm...

  6. Development of Testing Methodologies to Evaluate Postflight Locomotor Performance

    Science.gov (United States)

    Mulavara, A. P.; Peters, B. T.; Cohen, H. S.; Richards, J. T.; Miller, C. A.; Brady, R.; Warren, L. E.; Bloomberg, J. J.

    2006-01-01

    Crewmembers experience locomotor and postural instabilities during ambulation on Earth following their return from space flight. Gait training programs designed to facilitate recovery of locomotor function following a transition to a gravitational environment need to be accompanied by relevant assessment methodologies to evaluate their efficacy. The goal of this paper is to demonstrate the operational validity of two tests of locomotor function that were used to evaluate performance after long duration space flight missions on the International Space Station (ISS).

  7. Optic flow improves adaptability of spatiotemporal characteristics during split-belt locomotor adaptation with tactile stimulation

    OpenAIRE

    Anthony Eikema, Diderik Jan A.; Chien, Jung Hung; Stergiou, Nicholas; Myers, Sara A.; Scott-Pandorf, Melissa M.; Bloomberg, Jacob J.; Mukherjee, Mukul

    2015-01-01

    Human locomotor adaptation requires feedback and feed-forward control processes to maintain an appropriate walking pattern. Adaptation may require the use of visual and proprioceptive input to decode altered movement dynamics and generate an appropriate response. After a person transfers from an extreme sensory environment and back, as astronauts do when they return from spaceflight, the prolonged period required for re-adaptation can pose a significant burden. In our previous paper, we showe...

  8. Capability ethics

    NARCIS (Netherlands)

    I.A.M. Robeyns (Ingrid)

    2012-01-01

    textabstractThe capability approach is one of the most recent additions to the landscape of normative theories in ethics and political philosophy. Yet in its present stage of development, the capability approach is not a full-blown normative theory, in contrast to utilitarianism, deontological

  9. Neuropharmacology of light-induced locomotor activation.

    Science.gov (United States)

    Amato, Davide; Pum, Martin E; Groos, Dominik; Lauber, Andrea C; Huston, Joseph P; Carey, Robert J; de Souza Silva, Maria A; Müller, Christian P

    2015-08-01

    Presentation of non-aversive light stimuli for several seconds was found to reliably induce locomotor activation and exploratory-like activity. Light-induced locomotor activity (LIA) can be considered a convenient simple model to study sensory-motor activation. LIA was previously shown to coincide with serotonergic and dopaminergic activation in specific cortical areas in freely moving and anesthetized animals. In the present study we explore the neuropharmacology of LIA using a receptor antagonist/agonist approach in rats. The non-selective 5-HT2-receptor antagonist ritanserin (1.5-6 mg/kg, i.p.) dose-dependently reduced LIA. Selective antagonism of either the 5-HT2A-receptor by MDL 11,939 (0.1-0.4 mg/kg, i.p.), or the 5-HT2C-receptor by SDZ SER 082 (0.125-0.5 mg/kg, i.p.), alone or in combination, had no significant influence on LIA. Also the selective 5-HT1A-receptor antagonist, WAY 100635 (0.4 mg/kg, i.p.) did not affect LIA. Neither did the preferential dopamine D2-receptor antagonist, haloperidol (0.025-0.1 mg/kg, i.p.) nor the D2/D3-receptor agonist, quinpirole (0.025-0.5 mg/kg, i.p.) affect the expression of LIA. However, blocking the glutamatergic NMDA-receptor with phencyclidine (PCP, 1.5-6 mg/kg, i.p.) dose-dependently reduced LIA. This effect was also observed with ketamine (10 mg/kg, i.p.). These findings suggest that serotonin and dopamine receptors abundantly expressed in the cortex do not mediate light-stimulus triggered locomotor activity. PCP and ketamine effects, however, suggest an important role of NMDA receptors in LIA. Copyright © 2015 Elsevier Ltd. All rights reserved.

  10. Capabilities for innovation

    DEFF Research Database (Denmark)

    Nielsen, Peter; Nielsen, Rene Nesgaard; Bamberger, Simon Grandjean

    2012-01-01

    is a survey that collected information from 601 firms belonging to the private urban sector in Denmark. The survey was carried out in late 2010. Keywords: dynamic capabilities/innovation/globalization/employee/employer cooperation/Nordic model Acknowledgment: The GOPA study was financed by grant 20080053113......Technological developments combined with increasing levels of competition related to the ongoing globalization imply that firms find themselves in dynamic, changing environments that call for dynamic capabilities. This challenges the internal human and organizational resources of firms in general...

  11. The precision of locomotor odometry in humans.

    Science.gov (United States)

    Durgin, Frank H; Akagi, Mikio; Gallistel, Charles R; Haiken, Woody

    2009-03-01

    Two experiments measured the human ability to reproduce locomotor distances of 4.6-100 m without visual feedback and compared distance production with time production. Subjects were not permitted to count steps. It was found that the precision of human odometry follows Weber's law that variability is proportional to distance. The coefficients of variation for distance production were much lower than those measured for time production for similar durations. Gait parameters recorded during the task (average step length and step frequency) were found to be even less variable suggesting that step integration could be the basis for non-visual human odometry.

  12. Either brain-derived neurotrophic factor or neurotrophin-3 only neurotrophin-producing grafts promote locomotor recovery in untrained spinalized cats.

    Science.gov (United States)

    Ollivier-Lanvin, Karen; Fischer, Itzhak; Tom, Veronica; Houlé, John D; Lemay, Michel A

    2015-01-01

    Background. Transplants of cellular grafts expressing a combination of 2 neurotrophic factors, brain-derived neurotrophic factor (BDNF) and neurotrophin-3 (NT-3) have been shown to promote and enhance locomotor recovery in untrained spinalized cats. Based on the time course of recovery and the absence of axonal growth through the transplants, we hypothesized that recovery was due to neurotrophin-mediated plasticity within the existing locomotor circuitry of the lumbar cord. Since BDNF and NT-3 have different effects on axonal sprouting and synaptic connectivity/strengthening, it becomes important to ascertain the contribution of each individual neurotrophins to recovery. Objective. We studied whether BDNF or NT-3 only producing cellular grafts would be equally effective at restoring locomotion in untrained spinal cats. Methods. Rat fibroblasts secreting one of the 2 neurotrophins were grafted into the T12 spinal transection site of adult cats. Four cats in each group (BDNF alone or NT-3 alone) were evaluated. Locomotor recovery was tested on a treadmill at 3 and 5 weeks post-transection/grafting. Results. Animals in both groups were capable of plantar weight-bearing stepping at speed up to 0.8 m/s as early as 3 weeks and locomotor capabilities were similar at 3 and 5 weeks for both types of graft. Conclusions. Even without locomotor training, either BDNF or NT-3 only producing grafts promote locomotor recovery in complete spinal animals. More clinically applicable delivery methods need to be developed. © The Author(s) 2014.

  13. Predictive and Reactive Locomotor Adaptability in Healthy Elderly: A Systematic Review and Meta-Analysis.

    Science.gov (United States)

    Bohm, Sebastian; Mademli, Lida; Mersmann, Falk; Arampatzis, Adamantios

    2015-12-01

    Locomotor adaptability is based on the implementation of error-feedback information from previous perturbations to predictively adapt to expected perturbations (feedforward) and to facilitate reactive responses in recurring unexpected perturbations ('savings'). The effect of aging on predictive and reactive adaptability is yet unclear. However, such understanding is fundamental for the design and application of effective interventions targeting fall prevention. We systematically searched the Web of Science, MEDLINE, Embase and Science Direct databases as well as the reference lists of the eligible articles. A study was included if it addressed an investigation of the locomotor adaptability in response to repeated mechanical movement perturbations of healthy older adults (≥60 years). The weighted average effect size (WAES) of the general adaptability (adaptive motor responses to repeated perturbations) as well as predictive (after-effects) and reactive adaptation (feedback responses to a recurring unexpected perturbation) was calculated and tested for an overall effect. A subgroup analysis was performed regarding the factor age group [i.e., young (≤35 years) vs. older adults]. Furthermore, the methodological study quality was assessed. The review process yielded 18 studies [1009 participants, 613 older adults (70 ± 4 years)], which used various kinds of locomotor tasks and perturbations. The WAES for the general locomotor adaptability was 1.21 [95% confidence interval (CI) 0.68-1.74, n = 11] for the older and 1.39 (95% CI 0.90-1.89, n = 10) for the young adults with a significant (p locomotor adaptability in general and predictive and reactive adaptation in particular remain highly effective in the elderly, showing only minor, not statistically significant age-related deficits. Consequently, interventions which use adaptation and learning paradigms including the application of the mechanisms responsible for an effective predictive and reactive dynamic stability

  14. The evolution of locomotor rhythmicity in tetrapods.

    Science.gov (United States)

    Ross, Callum F; Blob, Richard W; Carrier, David R; Daley, Monica A; Deban, Stephen M; Demes, Brigitte; Gripper, Janaya L; Iriarte-Diaz, Jose; Kilbourne, Brandon M; Landberg, Tobias; Polk, John D; Schilling, Nadja; Vanhooydonck, Bieke

    2013-04-01

    Differences in rhythmicity (relative variance in cycle period) among mammal, fish, and lizard feeding systems have been hypothesized to be associated with differences in their sensorimotor control systems. We tested this hypothesis by examining whether the locomotion of tachymetabolic tetrapods (birds and mammals) is more rhythmic than that of bradymetabolic tetrapods (lizards, alligators, turtles, salamanders). Species averages of intraindividual coefficients of variation in cycle period were compared while controlling for gait and substrate. Variance in locomotor cycle periods is significantly lower in tachymetabolic than in bradymetabolic animals for datasets that include treadmill locomotion, non-treadmill locomotion, or both. When phylogenetic relationships are taken into account the pooled analyses remain significant, whereas the non-treadmill and the treadmill analyses become nonsignificant. The co-occurrence of relatively high rhythmicity in both feeding and locomotor systems of tachymetabolic tetrapods suggests that the anatomical substrate of rhythmicity is in the motor control system, not in the musculoskeletal components. © 2012 The Author(s). Evolution© 2012 The Society for the Study of Evolution.

  15. Development of a coupled dynamics code with transport theory capability and application to accelerator driven systems transients

    International Nuclear Information System (INIS)

    Cahalan, J.E.; Ama, T.; Palmiotti, G.; Taiwo, T.A.; Yang, W.S.

    2000-01-01

    The VARIANT-K and DIF3D-K nodal spatial kinetics computer codes have been coupled to the SAS4A and SASSYS-1 liquid metal reactor accident and systems analysis codes. SAS4A and SASSYS-1 have been extended with the addition of heavy liquid metal (Pb and Pb-Bi) thermophysical properties, heat transfer correlations, and fluid dynamics correlations. The coupling methodology and heavy liquid metal modeling additions are described. The new computer code suite has been applied to analysis of neutron source and thermal-hydraulics transients in a model of an accelerator-driven minor actinide burner design proposed in an OECD/NEA/NSC benchmark specification. Modeling assumptions and input data generation procedures are described. Results of transient analyses are reported, with emphasis on comparison of P1 and P3 variational nodal transport theory results with nodal diffusion theory results, and on significance of spatial kinetics effects

  16. Comparison of the Relationship between Lying and Standing Ultrasonography Measures of Muscle Morphology with Isometric and Dynamic Force Production Capabilities

    Directory of Open Access Journals (Sweden)

    John P. Wagle

    2017-11-01

    Full Text Available The purpose of the current study was (1 to examine the differences between standing and lying measures of vastus lateralis (VL, muscle thickness (MT, pennation angle (PA, and cross-sectional area (CSA using ultrasonography; and (2 to explore the relationships between lying and standing measures with isometric and dynamic assessments of force production—specifically peak force, rate of force development (RFD, impulse, and one-repetition maximum back squat. Fourteen resistance-trained subjects (age = 26.8 ± 4.0 years, height = 181.4 ± 6.0 cm, body mass = 89.8 ± 10.7 kg, back squat to body mass ratio = 1.84 ± 0.34 agreed to participate. Lying and standing ultrasonography images of the right VL were collected following 48 hours of rest. Isometric squat assessments followed ultrasonography, and were performed on force platforms with data used to determine isometric peak force (IPF, as well as RFD and impulse at various time points. Forty-eight hours later, one-repetition maximum back squats were performed by each subject. Paired-samples t-tests revealed statistically significant differences between standing and lying measurements of MT (p < 0.001, PA (p < 0.001, and CSA (p ≤ 0.05, with standing values larger in all cases. Further, standing measures were correlated more strongly and abundantly to isometric and dynamic performance. These results suggest that if practitioners intend to gain insight into strength-power potential based on ultrasonography measurements, performing the measurement collection with the athlete in a standing posture may be preferred.

  17. Enhanced persistency of resting and active periods of locomotor activity in schizophrenia.

    Directory of Open Access Journals (Sweden)

    Wataru Sano

    Full Text Available Patients with schizophrenia frequently exhibit behavioral abnormalities associated with its pathological symptoms. Therefore, a quantitative evaluation of behavioral dynamics could contribute to objective diagnoses of schizophrenia. However, such an approach has not been fully established because of the absence of quantitative biobehavioral measures. Recently, we studied the dynamical properties of locomotor activity, specifically how resting and active periods are interwoven in daily life. We discovered universal statistical laws ("behavioral organization" and their alterations in patients with major depressive disorder. In this study, we evaluated behavioral organization of schizophrenic patients (n = 19 and healthy subjects (n = 11 using locomotor activity data, acquired by actigraphy, to investigate whether the laws could provide objective and quantitative measures for a possible diagnosis and assessment of symptoms. Specifically, we evaluated the cumulative distributions of resting and active periods, defined as the periods with physical activity counts successively below and above a predefined threshold, respectively. Here we report alterations in the laws governing resting and active periods; resting periods obeyed a power-law cumulative distribution with significantly lower parameter values (power-law scaling exponents, whereas active periods followed a stretched exponential distribution with significantly lower parameter values (stretching exponents, in patients. Our findings indicate enhanced persistency of both lower and higher locomotor activity periods in patients with schizophrenia, probably reflecting schizophrenic pathophysiology.

  18. InfoSymbiotics/DDDAS - The power of Dynamic Data Driven Applications Systems for New Capabilities in Environmental -, Geo-, and Space- Sciences

    Science.gov (United States)

    Darema, F.

    2016-12-01

    InfoSymbiotics/DDDAS embodies the power of Dynamic Data Driven Applications Systems (DDDAS), a concept whereby an executing application model is dynamically integrated, in a feed-back loop, with the real-time data-acquisition and control components, as well as other data sources of the application system. Advanced capabilities can be created through such new computational approaches in modeling and simulations, and in instrumentation methods, and include: enhancing the accuracy of the application model; speeding-up the computation to allow faster and more comprehensive models of a system, and create decision support systems with the accuracy of full-scale simulations; in addition, the notion of controlling instrumentation processes by the executing application results in more efficient management of application-data and addresses challenges of how to architect and dynamically manage large sets of heterogeneous sensors and controllers, an advance over the static and ad-hoc ways of today - with DDDAS these sets of resources can be managed adaptively and in optimized ways. Large-Scale-Dynamic-Data encompasses the next wave of Big Data, and namely dynamic data arising from ubiquitous sensing and control in engineered, natural, and societal systems, through multitudes of heterogeneous sensors and controllers instrumenting these systems, and where opportunities and challenges at these "large-scales" relate not only to data size but the heterogeneity in data, data collection modalities, fidelities, and timescales, ranging from real-time data to archival data. In tandem with this important dimension of dynamic data, there is an extended view of Big Computing, which includes the collective computing by networked assemblies of multitudes of sensors and controllers, this range from the high-end to the real-time seamlessly integrated and unified, and comprising the Large-Scale-Big-Computing. InfoSymbiotics/DDDAS engenders transformative impact in many application domains

  19. PROBLEMAS LOCOMOTORES EM FRANGOS DE CORTE - REVISÃO. / LOCOMOTOR PROBLEMS IN BROILER CHICKENS - A REVIEW.

    Directory of Open Access Journals (Sweden)

    IBIARA CORREIA DE LIMA ALMEIDA PAZ

    2008-12-01

    Full Text Available O bem estar animal é, sem dúvida, um dos pontos em que os produtores de aves devem se atentar para conseguir melhor rentabilidade e colocação no mercado externo. No entanto, é necessário ter uma ampla idéia de que alguns pontos impostos por mercados importadores, muitas vezes não tem fundamento científico e tratam-se mais de barreiras não tarifárias que de problemas de produção propriamente ditos. Dentre os vários fatores que afetam o bem estar animal pode-se destacar a incidência de problemas locomotores, principalmente em animais confinados. Estes distúrbios podem acarretar em perdas de até 6% em lotes comercias de frangos de corte, além de outras perdas não mensuráveis em linhas de abate, por fraturas e hematomas. Existem diversas metodologias para diagnosticar problemas locomotores, entretanto, a mais difundida na indústria avícola é o Gait Score, por sua facilidade de aplicação e por englobar os diferentes tipos de problemas locomotores. Sabe-se, contudo que esta metodologia é bastante subjetiva e pode inferir  em  diferentes  níveis  de  avaliação  dependendo  do método  utilizado. Os  problemas locomotores devem ser prevenidos já que depois de estabelecidos as perdas são inevitáveis.

  20. Locomotor sequence learning in visually guided walking

    DEFF Research Database (Denmark)

    Choi, Julia T; Jensen, Peter; Nielsen, Jens Bo

    2016-01-01

    walking. In addition, we determined how age (i.e., healthy young adults vs. children) and biomechanical factors (i.e., walking speed) affected the rate and magnitude of locomotor sequence learning. The results showed that healthy young adults (age 24 ± 5 years, N = 20) could learn a specific sequence...... of step lengths over 300 training steps. Younger children (age 6-10 years, N = 8) have lower baseline performance, but their magnitude and rate of sequence learning was the same compared to older children (11-16 years, N = 10) and healthy adults. In addition, learning capacity may be more limited...... to modify step length from one trial to the next. Our sequence learning paradigm is derived from the serial reaction-time (SRT) task that has been used in upper limb studies. Both random and ordered sequences of step lengths were used to measure sequence-specific and sequence non-specific learning during...

  1. Integrated Locomotor Function Tests for Countermeasure Evaluation

    Science.gov (United States)

    Bloomberg, J. J.; Mulavara, A. P.; Peters, B. T.; Cohen, H. S.; Landsness, E. C.; Black, F. O.

    2005-01-01

    Following spaceflight crewmembers experience locomotor dysfunction due to inflight adaptive alterations in sensorimotor function. Countermeasures designed to mitigate these postflight gait alterations need to be assessed with a new generation of tests that evaluate the interaction of various sensorimotor sub-systems central to locomotor control. The goal of the present study was to develop new functional tests of locomotor control that could be used to test the efficacy of countermeasures. These tests were designed to simultaneously examine the function of multiple sensorimotor systems underlying the control of locomotion and be operationally relevant to the astronaut population. Traditionally, gaze stabilization has been studied almost exclusively in seated subjects performing target acquisition tasks requiring only the involvement of coordinated eye-head movements. However, activities like walking involve full-body movement and require coordination between lower limbs and the eye-head-trunk complex to achieve stabilized gaze during locomotion. Therefore the first goal of this study was to determine how the multiple, interdependent, full-body sensorimotor gaze stabilization subsystems are functionally coordinated during locomotion. In an earlier study we investigated how alteration in gaze tasking changes full-body locomotor control strategies. Subjects walked on a treadmill and either focused on a central point target or read numeral characters. We measured: temporal parameters of gait, full body sagittal plane segmental kinematics of the head, trunk, thigh, shank and foot, accelerations along the vertical axis at the head and the shank, and the vertical forces acting on the support surface. In comparison to the point target fixation condition, the results of the number reading task showed that compensatory head pitch movements increased, peak head acceleration was reduced and knee flexion at heel-strike was increased. In a more recent study we investigated the

  2. Capability approach

    DEFF Research Database (Denmark)

    Jensen, Niels Rosendal; Kjeldsen, Christian Christrup

    Lærebogen er den første samlede danske præsentation af den af Amartya Sen og Martha Nussbaum udviklede Capability Approach. Bogen indeholder en præsentation og diskussion af Sen og Nussbaums teoretiske platform. I bogen indgår eksempler fra såvel uddannelse/uddannelsespolitik, pædagogik og omsorg....

  3. Effect of thermal acclimation on locomotor energetics and locomotor performance in a lungless salamander, Desmognathus ochrophaeus.

    Science.gov (United States)

    Feder, M E

    1986-03-01

    To determine the effects of thermal acclimation upon locomotor performance and the rate of oxygen consumption (MO2) during activity, small (less than 3 g), lungless salamanders, Desmognathus ochrophaeus Cope, were acclimated to three temperatures (5, 13 and 21 degrees C) and exercised at various controlled speeds within an exercise wheel while their MO2 was measured. MO2 increased with speed at low speeds (less than 14 cm min-1). Although animals could sustain greater speeds, MO2 did not increase further. These small, exclusively skin-breathing salamanders could increase their MO2 9-11 times during exercise and could sustain nearly half of the oxygen flux expected across a similar surface area of the mammalian lung. However, their maximum aerobic speed was remarkably slow (14 cm min-1) and their net cost of transport remarkably large (15-17 ml O2 g-1 km-1). Thermal acclimation affected MO2 during activity, the maximum sustainable speed and locomotor stamina in different ways. During exercise at 13 degrees C, cold-acclimated animals had a significantly greater MO2 than warm-acclimated animals, but did not differ in stamina or the maximum sustainable speed. During exercise at 21 degrees C, cold acclimation did not affect the MO2 significantly, but it decreased the stamina and increased the rate of lactate accumulation. Thus, these results suggest that thermal acclimation of the MO2 is not tightly coupled to thermal acclimation of locomotor performance in salamanders.

  4. ENTREPRENEURIAL CAPABILITIES

    DEFF Research Database (Denmark)

    Rasmussen, Lauge Baungaard; Nielsen, Thorkild

    2003-01-01

    The aim of this article is to analyse entrepreneurship from an action research perspective. What is entrepreneurship about? Which are the fundamental capabilities and processes of entrepreneurship? To answer these questions the article includes a case study of a Danish entrepreneur and his networ....... Finally, the article discuss, how more long term action research methods could be integrated into the entrepreneurial processes and the possible impacts of such an implementation?...

  5. Advancing methods for research on household water insecurity: Studying entitlements and capabilities, socio-cultural dynamics, and political processes, institutions and governance.

    Science.gov (United States)

    Wutich, Amber; Budds, Jessica; Eichelberger, Laura; Geere, Jo; Harris, Leila; Horney, Jennifer; Jepson, Wendy; Norman, Emma; O'Reilly, Kathleen; Pearson, Amber; Shah, Sameer; Shinn, Jamie; Simpson, Karen; Staddon, Chad; Stoler, Justin; Teodoro, Manuel P; Young, Sera

    2017-11-01

    Household water insecurity has serious implications for the health, livelihoods and wellbeing of people around the world. Existing methods to assess the state of household water insecurity focus largely on water quality, quantity or adequacy, source or reliability, and affordability. These methods have significant advantages in terms of their simplicity and comparability, but are widely recognized to oversimplify and underestimate the global burden of household water insecurity. In contrast, a broader definition of household water insecurity should include entitlements and human capabilities, sociocultural dynamics, and political institutions and processes. This paper proposes a mix of qualitative and quantitative methods that can be widely adopted across cultural, geographic, and demographic contexts to assess hard-to-measure dimensions of household water insecurity. In doing so, it critically evaluates existing methods for assessing household water insecurity and suggests ways in which methodological innovations advance a broader definition of household water insecurity.

  6. Dynamic Primitives in the Control of Locomotion

    Directory of Open Access Journals (Sweden)

    Neville eHogan

    2013-06-01

    Full Text Available Humans achieve locomotor dexterity that far exceeds the capability of modern robots, yet this is achieved despite slower actuators, imprecise sensors and vastly slower communication. We propose that this spectacular performance arises from encoding motor commands in terms of dynamic primitives. We propose three primitives as a foundation for a comprehensive theoretical framework that can embrace a wide range of upper- and lower-limb behaviors. Building on previous work that suggested discrete and rhythmic movements as elementary dynamic behaviors, we define submovements and oscillations: As discrete movements cannot be combined with sufficient flexibility, we argue that suitably-defined submovements are primitives. As the term rhythmic may be ambiguous, we define oscillations as the corresponding class of primitives. We further propose mechanical impedances as a third class of dynamic primitives, necessary for interaction with the physical environment. Combination of these three classes of primitive requires care. One approach is through a generalized equivalent network: a virtual trajectory composed of simultaneous and/or sequential submovements and/or oscillations that interacts with mechanical impedances to produce observable forces and motions. Reliable experimental identification of these dynamic primitives presents challenges: Identification of mechanical impedances is exquisitely sensitive to assumptions about their dynamic structure; identification of submovements and oscillations is sensitive to their assumed form and to details of the algorithm used to extract them. Some methods to address these challenges are presented. Some implications of this theoretical framework for locomotor rehabilitation are considered.

  7. Dynamic primitives in the control of locomotion.

    Science.gov (United States)

    Hogan, Neville; Sternad, Dagmar

    2013-01-01

    Humans achieve locomotor dexterity that far exceeds the capability of modern robots, yet this is achieved despite slower actuators, imprecise sensors, and vastly slower communication. We propose that this spectacular performance arises from encoding motor commands in terms of dynamic primitives. We propose three primitives as a foundation for a comprehensive theoretical framework that can embrace a wide range of upper- and lower-limb behaviors. Building on previous work that suggested discrete and rhythmic movements as elementary dynamic behaviors, we define submovements and oscillations: as discrete movements cannot be combined with sufficient flexibility, we argue that suitably-defined submovements are primitives. As the term "rhythmic" may be ambiguous, we define oscillations as the corresponding class of primitives. We further propose mechanical impedances as a third class of dynamic primitives, necessary for interaction with the physical environment. Combination of these three classes of primitive requires care. One approach is through a generalized equivalent network: a virtual trajectory composed of simultaneous and/or sequential submovements and/or oscillations that interacts with mechanical impedances to produce observable forces and motions. Reliable experimental identification of these dynamic primitives presents challenges: identification of mechanical impedances is exquisitely sensitive to assumptions about their dynamic structure; identification of submovements and oscillations is sensitive to their assumed form and to details of the algorithm used to extract them. Some methods to address these challenges are presented. Some implications of this theoretical framework for locomotor rehabilitation are considered.

  8. Locomotor differences in Mongolian gerbils with the effects of ...

    African Journals Online (AJOL)

    Locomotor differences in Mongolian gerbils with the effects of midazolam ... African Health Sciences ... We subjected the gerbils to an adapted “Open Field” to determine the possible effects on central nervous system of midazolam. Gerbils ...

  9. Hesperidin effects on behavior and locomotor activity of diabetic ...

    African Journals Online (AJOL)

    Tuoyo Aghomotsegin

    2016-11-09

    Nov 9, 2016 ... Author(s) agree that this article remains permanently open access under the terms of the Creative ... diabetes in animals and patients with type1 (Northam et ... measured were, locomotor activities, standing position, the time of.

  10. The anatomy and physiology of the locomotor system.

    Science.gov (United States)

    Farley, Alistair; McLafferty, Ella; Hendry, Charles

    Mobilisation is one of the activities of living. The term locomotor system refers to those body tissues and organs responsible for movement. Nurses and healthcare workers should be familiar with the body structures that enable mobilisation to assist those in their care with this activity. This article outlines the structure and function of the locomotor system, including the skeleton, joints, muscles and muscle attachments. Two common bone disorders, osteoporosis and osteoarthritis, are also considered.

  11. Limitations to the Generality of Cocaine Locomotor Sensitization

    OpenAIRE

    Marusich, Julie A.; Branch, Marc N.; Dallery, Jesse

    2008-01-01

    Repeated exposure to cocaine often leads to tolerance to effects on operant behavior, whereas sensitization often develops to effects on locomotor activity. The purpose of the present set of experiments was to examine if locomotor sensitization to cocaine would develop in the presence or absence of an operant contingency in rats. In Experiment 1, rats lever pressed on an FR schedule of reinforcement, and were administered chronic cocaine. Tolerance to effects of cocaine on lever pressing deve...

  12. Modular Diversification of the Locomotor System in Damselfishes (Pomacentridae)

    OpenAIRE

    Aguilar-Medrano, Rosalia; Frederich, Bruno; Barber, Paul H.

    2016-01-01

    As fish move and interact with their aquatic environment by swimming, small morphological variations of the locomotor system can have profound implications on fitness. Damselfishes (Pomacentridae) have inhabited coral reef ecosystems for more than 50 million years. As such, habitat preferences and behavior could significantly constrain the morphology and evolvability of the locomotor system. To test this hypothesis, we used phylogenetic comparative methods on morphometric, ecological and beha...

  13. Role of spared pathways in locomotor recovery after body-weight-supported treadmill training in contused rats.

    Science.gov (United States)

    Singh, Anita; Balasubramanian, Sriram; Murray, Marion; Lemay, Michel; Houle, John

    2011-12-01

    Body-weight-supported treadmill training (BWSTT)-related locomotor recovery has been shown in spinalized animals. Only a few animal studies have demonstrated locomotor recovery after BWSTT in an incomplete spinal cord injury (SCI) model, such as contusion injury. The contribution of spared descending pathways after BWSTT to behavioral recovery is unclear. Our goal was to evaluate locomotor recovery in contused rats after BWSTT, and to study the role of spared pathways in spinal plasticity after BWSTT. Forty-eight rats received a contusion, a transection, or a contusion followed at 9 weeks by a second transection injury. Half of the animals in the three injury groups were given BWSTT for up to 8 weeks. Kinematics and the Basso-Beattie-Bresnahan (BBB) test assessed behavioral improvements. Changes in Hoffmann-reflex (H-reflex) rate depression property, soleus muscle mass, and sprouting of primary afferent fibers were also evaluated. BWSTT-contused animals showed accelerated locomotor recovery, improved H-reflex properties, reduced muscle atrophy, and decreased sprouting of small caliber afferent fibers. BBB scores were not improved by BWSTT. Untrained contused rats that received a transection exhibited a decrease in kinematic parameters immediately after the transection; in contrast, trained contused rats did not show an immediate decrease in kinematic parameters after transection. This suggests that BWSTT with spared descending pathways leads to neuroplasticity at the lumbar spinal level that is capable of maintaining locomotor activity. Discontinuing training after the transection in the trained contused rats abolished the improved kinematics within 2 weeks and led to a reversal of the improved H-reflex response, increased muscle atrophy, and an increase in primary afferent fiber sprouting. Thus continued training may be required for maintenance of the recovery. Transected animals had no effect of BWSTT, indicating that in the absence of spared pathways this

  14. Adaptive locomotor behavior in larval zebrafish.

    Science.gov (United States)

    Portugues, Ruben; Engert, Florian

    2011-01-01

    In this study we report that larval zebrafish display adaptive locomotor output that can be driven by unexpected visual feedback. We develop a new assay that addresses visuomotor integration in restrained larval zebrafish. The assay involves a closed-loop environment in which the visual feedback a larva receives depends on its own motor output in a way that resembles freely swimming conditions. The experimenter can control the gain of this closed feedback loop, so that following a given motor output the larva experiences more or less visual feedback depending on whether the gain is high or low. We show that increases and decreases in this gain setting result in adaptive changes in behavior that lead to a generalized decrease or increase of motor output, respectively. Our behavioral analysis shows that both the duration and tail beat frequency of individual swim bouts can be modified, as well as the frequency with which bouts are elicited. These changes can be implemented rapidly, following an exposure to a new gain of just 175 ms. In addition, modifications in some behavioral parameters accumulate over tens of seconds and effects last for at least 30 s from trial to trial. These results suggest that larvae establish an internal representation of the visual feedback expected from a given motor output and that the behavioral modifications are driven by an error signal that arises from the discrepancy between this expectation and the actual visual feedback. The assay we develop presents a unique possibility for studying visuomotor integration using imaging techniques available in the larval zebrafish.

  15. Locomotor training improves premotoneuronal control after chronic spinal cord injury.

    Science.gov (United States)

    Knikou, Maria; Mummidisetty, Chaithanya K

    2014-06-01

    Spinal inhibition is significantly reduced after spinal cord injury (SCI) in humans. In this work, we examined if locomotor training can improve spinal inhibition exerted at a presynaptic level. Sixteen people with chronic SCI received an average of 45 training sessions, 5 days/wk, 1 h/day. The soleus H-reflex depression in response to low-frequency stimulation, presynaptic inhibition of soleus Ia afferent terminals following stimulation of the common peroneal nerve, and bilateral EMG recovery patterns were assessed before and after locomotor training. The soleus H reflexes evoked at 1.0, 0.33, 0.20, 0.14, and 0.11 Hz were normalized to the H reflex evoked at 0.09 Hz. Conditioned H reflexes were normalized to the associated unconditioned H reflex evoked with subjects seated, while during stepping both H reflexes were normalized to the maximal M wave evoked after the test H reflex at each bin of the step cycle. Locomotor training potentiated homosynaptic depression in all participants regardless the type of the SCI. Presynaptic facilitation of soleus Ia afferents remained unaltered in motor complete SCI patients. In motor incomplete SCIs, locomotor training either reduced presynaptic facilitation or replaced presynaptic facilitation with presynaptic inhibition at rest. During stepping, presynaptic inhibition was modulated in a phase-dependent manner. Locomotor training changed the amplitude of locomotor EMG excitability, promoted intralimb and interlimb coordination, and altered cocontraction between knee and ankle antagonistic muscles differently in the more impaired leg compared with the less impaired leg. The results provide strong evidence that locomotor training improves premotoneuronal control after SCI in humans at rest and during walking. Copyright © 2014 the American Physiological Society.

  16. Adaptive control of two-wheeled mobile balance robot capable to adapt different surfaces using a novel artificial neural network–based real-time switching dynamic controller

    Directory of Open Access Journals (Sweden)

    Ali Unluturk

    2017-03-01

    Full Text Available In this article, a novel real-time artificial neural network–based adaptable switching dynamic controller is developed and practically implemented. It will be used for real-time control of two-wheeled balance robot which can balance itself upright position on different surfaces. In order to examine the efficiency of the proposed controller, a two-wheeled mobile balance robot is designed and a test platform for experimental setup is made for balance problem on different surfaces. In a developed adaptive controller algorithm which is capable to adapt different surfaces, mean absolute target angle deviation error, mean absolute target displacement deviation error and mean absolute controller output data are employed for surface estimation by using artificial neural network. In a designed two-wheeled mobile balance robot system, robot tilt angle is estimated via Kalman filter from accelerometer and gyroscope sensor signals. Furthermore, a visual robot control interface is developed in C++ software development environment so that robot controller parameters can be changed as desired. In addition, robot balance angle, linear displacement and controller output can be observed online on personal computer. According to the real-time experimental results, the proposed novel type controller gives more effective results than the classic ones.

  17. Modular diversification of the locomotor system in damselfishes (Pomacentridae).

    Science.gov (United States)

    Aguilar-Medrano, Rosalía; Frédérich, Bruno; Barber, Paul H

    2016-05-01

    As fish move and interact with their aquatic environment by swimming, small morphological variations of the locomotor system can have profound implications on fitness. Damselfishes (Pomacentridae) have inhabited coral reef ecosystems for more than 50 million years. As such, habitat preferences and behavior could significantly constrain the morphology and evolvability of the locomotor system. To test this hypothesis, we used phylogenetic comparative methods on morphometric, ecological and behavioral data. While body elongation represented the primary source of variation in the locomotor system of damselfishes, results also showed a diverse suite of morphological combinations between extreme morphologies. Results show clear associations between behavior, habitat preferences, and morphology, suggesting ecological constraints on shape diversification of the locomotor system. In addition, results indicate that the three modules of the locomotor system are weakly correlated, resulting in versatile and independent characters. These results suggest that Pomacentridae is shape may result from the interaction between (1) integrated parts of morphological variation that maintain overall swimming ability and (2) relatively independent parts of the morphology that facilitate adaptation and diversification. © 2016 Wiley Periodicals, Inc.

  18. Stimulation of the mesencephalic locomotor region for gait recovery after stroke.

    Science.gov (United States)

    Fluri, Felix; Malzahn, Uwe; Homola, György A; Schuhmann, Michael K; Kleinschnitz, Christoph; Volkmann, Jens

    2017-11-01

    One-third of all stroke survivors are unable to walk, even after intensive physiotherapy. Thus, other concepts to restore walking are needed. Because electrical stimulation of the mesencephalic locomotor region (MLR) is known to elicit gait movements, this area might be a promising target for restorative neurostimulation in stroke patients with gait disability. The present study aims to delineate the effect of high-frequency stimulation of the MLR (MLR-HFS) on gait impairment in a rodent stroke model. Male Wistar rats underwent photothrombotic stroke of the right sensorimotor cortex and chronic implantation of a stimulating electrode into the right MLR. Gait was assessed using clinical scoring of the beam-walking test and video-kinematic analysis (CatWalk) at baseline and on days 3 and 4 after experimental stroke with and without MLR-HFS. Kinematic analysis revealed significant changes in several dynamic and static gait parameters resulting in overall reduced gait velocity. All rats exhibited major coordination deficits during the beam-walking challenge and were unable to cross the beam. Simultaneous to the onset of MLR-HFS, a significantly higher walking speed and improvements in several dynamic gait parameters were detected by the CatWalk system. Rats regained the ability to cross the beam unassisted, showing a reduced number of paw slips and misses. MLR-HFS can improve disordered locomotor function in a rodent stroke model. It may act by shielding brainstem and spinal locomotor centers from abnormal cortical input after stroke, thus allowing for compensatory and independent action of these circuits. Ann Neurol 2017;82:828-840. © 2017 American Neurological Association.

  19. Quaternary naltrexone reverses radiogenic and morphine-induced locomotor hyperactivity

    Energy Technology Data Exchange (ETDEWEB)

    Mickley, G.A.; Stevens, K.E.; Galbraith, J.A.; White, G.A.; Gibbs, G.L.

    1984-04-01

    The present study attempted to determine the relative role of the peripheral and central nervous system in the production of morphine-induced or radiation-induced locomotor hyperactivity of the mouse. Toward this end, we used a quaternary derivative of an opiate antagonist (naltrexone methobromide), which presumably does not cross the blood-brain barrier. Quaternary naltrexone was used to challenge the stereotypic locomotor response observed in these mice after either an i.p. injection of morphine or exposure to 1500 rads /sup 60/Co. The quaternary derivative of naltrexone reversed the locomotor hyperactivity normally observed in the C57BL/6J mouse after an injection of morphine. It also significantly attenuated radiation-induced locomotion. The data reported here support the hypothesis of endorphin involvement in radiation-induced and radiogenic behaviors. However, these conclusions are contingent upon further research which more fully evaluates naltrexone methobromide's capacity to cross the blood-brain barrier.

  20. Delineating the Diversity of Spinal Interneurons in Locomotor Circuits.

    Science.gov (United States)

    Gosgnach, Simon; Bikoff, Jay B; Dougherty, Kimberly J; El Manira, Abdeljabbar; Lanuza, Guillermo M; Zhang, Ying

    2017-11-08

    Locomotion is common to all animals and is essential for survival. Neural circuits located in the spinal cord have been shown to be necessary and sufficient for the generation and control of the basic locomotor rhythm by activating muscles on either side of the body in a specific sequence. Activity in these neural circuits determines the speed, gait pattern, and direction of movement, so the specific locomotor pattern generated relies on the diversity of the neurons within spinal locomotor circuits. Here, we review findings demonstrating that developmental genetics can be used to identify populations of neurons that comprise these circuits and focus on recent work indicating that many of these populations can be further subdivided into distinct subtypes, with each likely to play complementary functions during locomotion. Finally, we discuss data describing the manner in which these populations interact with each other to produce efficient, task-dependent locomotion. Copyright © 2017 the authors 0270-6474/17/3710835-07$15.00/0.

  1. Locomotor adaptability in persons with unilateral transtibial amputation.

    Science.gov (United States)

    Darter, Benjamin J; Bastian, Amy J; Wolf, Erik J; Husson, Elizabeth M; Labrecque, Bethany A; Hendershot, Brad D

    2017-01-01

    Locomotor adaptation enables walkers to modify strategies when faced with challenging walking conditions. While a variety of neurological injuries can impair locomotor adaptability, the effect of a lower extremity amputation on adaptability is poorly understood. Determine if locomotor adaptability is impaired in persons with unilateral transtibial amputation (TTA). The locomotor adaptability of 10 persons with a TTA and 8 persons without an amputation was tested while walking on a split-belt treadmill with the parallel belts running at the same (tied) or different (split) speeds. In the split condition, participants walked for 15 minutes with the respective belts moving at 0.5 m/s and 1.5 m/s. Temporal spatial symmetry measures were used to evaluate reactive accommodations to the perturbation, and the adaptive/de-adaptive response. Persons with TTA and the reference group of persons without amputation both demonstrated highly symmetric walking at baseline. During the split adaptation and tied post-adaptation walking both groups responded with the expected reactive accommodations. Likewise, adaptive and de-adaptive responses were observed. The magnitude and rate of change in the adaptive and de-adaptive responses were similar for persons with TTA and those without an amputation. Furthermore, adaptability was no different based on belt assignment for the prosthetic limb during split adaptation walking. Reactive changes and locomotor adaptation in response to a challenging and novel walking condition were similar in persons with TTA to those without an amputation. Results suggest persons with TTA have the capacity to modify locomotor strategies to meet the demands of most walking conditions despite challenges imposed by an amputation and use of a prosthetic limb.

  2. Anatomía del Aparato Locomotor, 2010-11

    OpenAIRE

    Juanes Méndez, Juan Antonio

    2010-01-01

    I. Materiales de clase: 1.Sistema Oseo. Las Articulaciones: definición, clasificaciones; 2.Esqueleto Axial; 3.Esqueleto Apendicular; 4. Organización del sistema nervioso periférico. Inervación del Aparato Locomotor; 5. Sistema muscular. II. Bibliografía y atlas Establecer la correlación morfofuncional del aparato locomotor necesaria para la deducción deficitaria derivada de las alteraciones de la dinámica osteoarticular. Esta asignatura se imparte en el primer curso del Grado en Terapia Oc...

  3. Transforming organizational capabilities in strategizing

    DEFF Research Database (Denmark)

    Jørgensen, Claus; Friis, Ole Uhrskov; Koch, Christian

    2014-01-01

    Offshored and networked enterprises are becoming an important if not leading organizational form and this development seriously challenges their organizational capabilities. More specifically, over the last years, SMEs have commenced entering these kinds of arrangements. As the organizational...... capabilities of SMEs are limited at the outset, even more emphasis is needed regarding the issues of developing relevant organizational capabilities. This paper aims at investigating how capabilities evolve during an offshoring process of more than 5 years in two Danish SMEs, i.e. not only short- but long......-term evolvements within the companies. We develop our framework of understanding organizational capabilities drawing on dynamic capability, relational capability and strategy as practice concepts, appreciating the performative aspects of developing new routines. Our two cases are taken from one author’s Ph...

  4. A neurorobotic platform for locomotor prosthetic development in rats and mice

    Science.gov (United States)

    von Zitzewitz, Joachim; Asboth, Leonie; Fumeaux, Nicolas; Hasse, Alexander; Baud, Laetitia; Vallery, Heike; Courtine, Grégoire

    2016-04-01

    Objectives. We aimed to develop a robotic interface capable of providing finely-tuned, multidirectional trunk assistance adjusted in real-time during unconstrained locomotion in rats and mice. Approach. We interfaced a large-scale robotic structure actuated in four degrees of freedom to exchangeable attachment modules exhibiting selective compliance along distinct directions. This combination allowed high-precision force and torque control in multiple directions over a large workspace. We next designed a neurorobotic platform wherein real-time kinematics and physiological signals directly adjust robotic actuation and prosthetic actions. We tested the performance of this platform in both rats and mice with spinal cord injury. Main Results. Kinematic analyses showed that the robotic interface did not impede locomotor movements of lightweight mice that walked freely along paths with changing directions and height profiles. Personalized trunk assistance instantly enabled coordinated locomotion in mice and rats with severe hindlimb motor deficits. Closed-loop control of robotic actuation based on ongoing movement features enabled real-time control of electromyographic activity in anti-gravity muscles during locomotion. Significance. This neurorobotic platform will support the study of the mechanisms underlying the therapeutic effects of locomotor prosthetics and rehabilitation using high-resolution genetic tools in rodent models.

  5. Engagement of the Rat Hindlimb Motor Cortex across Natural Locomotor Behaviors.

    Science.gov (United States)

    DiGiovanna, Jack; Dominici, Nadia; Friedli, Lucia; Rigosa, Jacopo; Duis, Simone; Kreider, Julie; Beauparlant, Janine; van den Brand, Rubia; Schieppati, Marco; Micera, Silvestro; Courtine, Grégoire

    2016-10-05

    Contrary to cats and primates, cortical contribution to hindlimb locomotor movements is not critical in rats. However, the importance of the motor cortex to regain locomotion after neurological disorders in rats suggests that cortical engagement in hindlimb motor control may depend on the behavioral context. To investigate this possibility, we recorded whole-body kinematics, muscle synergies, and hindlimb motor cortex modulation in freely moving rats performing a range of natural locomotor procedures. We found that the activation of hindlimb motor cortex preceded gait initiation. During overground locomotion, the motor cortex exhibited consistent neuronal population responses that were synchronized with the spatiotemporal activation of hindlimb motoneurons. Behaviors requiring enhanced muscle activity or skilled paw placement correlated with substantial adjustment in neuronal population responses. In contrast, all rats exhibited a reduction of cortical activity during more automated behavior, such as stepping on a treadmill. Despite the facultative role of the motor cortex in the production of locomotion in rats, these results show that the encoding of hindlimb features in motor cortex dynamics is comparable in rats and cats. However, the extent of motor cortex modulations appears linked to the degree of volitional engagement and complexity of the task, reemphasizing the importance of goal-directed behaviors for motor control studies, rehabilitation, and neuroprosthetics. We mapped the neuronal population responses in the hindlimb motor cortex to hindlimb kinematics and hindlimb muscle synergies across a spectrum of natural locomotion behaviors. Robust task-specific neuronal population responses revealed that the rat motor cortex displays similar modulation as other mammals during locomotion. However, the reduced motor cortex activity during more automated behaviors suggests a relationship between the degree of engagement and task complexity. This relationship

  6. Olanzapine affects locomotor activity and meal size in male rats

    NARCIS (Netherlands)

    van der Zwaal, Esther M.; Luijendijk, Mieneke C. M.; Evers, Simon S.; la Fleur, Susanne E.; Adan, Roger A. H.

    2010-01-01

    Olanzapine is an antipsychotic drug that frequently induces weight gain accompanied by increased fat deposition as a side effect To investigate how olanzapine affects different aspects of energy balance we used male rats to determine effects on meal patterns food preference locomotor activity and

  7. Olanzapine affects locomotor activity and meal size in male rats

    NARCIS (Netherlands)

    van der Zwaal, Esther M.; Luijendijk, Mieneke C. M.; Evers, Simon S.; la Fleur, Susanne E.; Adan, Roger A. H.

    2010-01-01

    Olanzapine is an antipsychotic drug that frequently induces weight gain accompanied by increased fat deposition as a side effect. To investigate how olanzapine affects different aspects of energy balance, we used male rats to determine effects on meal patterns, food preference, locomotor activity

  8. Inbreeding affects locomotor activity in Drosophila melanogaster at different ages

    DEFF Research Database (Denmark)

    Manenti, Tommaso; Pertoldi, Cino; Nasiri Moghadam, Neda

    2015-01-01

    The ability to move is essential for many behavioural traits closely related to fitness. Here we studied the effect of inbreeding on locomotor activity (LA) of Drosophila melanogaster at different ages under both dark and light regimes. We expected to find a decreased LA in inbred lines compared...

  9. Locomotor Sub-functions for Control of Assistive Wearable Robots

    Directory of Open Access Journals (Sweden)

    Maziar A. Sharbafi

    2017-09-01

    Full Text Available A primary goal of comparative biomechanics is to understand the fundamental physics of locomotion within an evolutionary context. Such an understanding of legged locomotion results in a transition from copying nature to borrowing strategies for interacting with the physical world regarding design and control of bio-inspired legged robots or robotic assistive devices. Inspired from nature, legged locomotion can be composed of three locomotor sub-functions, which are intrinsically interrelated: Stance: redirecting the center of mass by exerting forces on the ground. Swing: cycling the legs between ground contacts. Balance: maintaining body posture. With these three sub-functions, one can understand, design and control legged locomotory systems with formulating them in simpler separated tasks. Coordination between locomotor sub-functions in a harmonized manner appears then as an additional problem when considering legged locomotion. However, biological locomotion shows that appropriate design and control of each sub-function simplifies coordination. It means that only limited exchange of sensory information between the different locomotor sub-function controllers is required enabling the envisioned modular architecture of the locomotion control system. In this paper, we present different studies on implementing different locomotor sub-function controllers on models, robots, and an exoskeleton in addition to demonstrating their abilities in explaining humans' control strategies.

  10. Locomotor Sub-functions for Control of Assistive Wearable Robots.

    Science.gov (United States)

    Sharbafi, Maziar A; Seyfarth, Andre; Zhao, Guoping

    2017-01-01

    A primary goal of comparative biomechanics is to understand the fundamental physics of locomotion within an evolutionary context. Such an understanding of legged locomotion results in a transition from copying nature to borrowing strategies for interacting with the physical world regarding design and control of bio-inspired legged robots or robotic assistive devices. Inspired from nature, legged locomotion can be composed of three locomotor sub-functions, which are intrinsically interrelated: Stance : redirecting the center of mass by exerting forces on the ground. Swing : cycling the legs between ground contacts. Balance : maintaining body posture. With these three sub-functions, one can understand, design and control legged locomotory systems with formulating them in simpler separated tasks. Coordination between locomotor sub-functions in a harmonized manner appears then as an additional problem when considering legged locomotion. However, biological locomotion shows that appropriate design and control of each sub-function simplifies coordination. It means that only limited exchange of sensory information between the different locomotor sub-function controllers is required enabling the envisioned modular architecture of the locomotion control system. In this paper, we present different studies on implementing different locomotor sub-function controllers on models, robots, and an exoskeleton in addition to demonstrating their abilities in explaining humans' control strategies.

  11. Efffects of vigabatrin on spontaneous locomotor activity of rats

    NARCIS (Netherlands)

    Bouwman, B.M.; Rijn, C.M. van; Willems-van Bree, P.C.M.; Coenen, A.M.L.

    2003-01-01

    Effects of vigibatrin (saline, 125, 250, or 500 mg/kg i.p.) on spontaneous locomotor activity in Wistar rats were investigated. There was a dose dependent decrease in amount of locomotion for doses up to 250 mg/kg. This decrease was measurable 2-4 hours after injection and still became more

  12. Locomotor sensitization to ethanol: Contribution of b-Endorphin

    Directory of Open Access Journals (Sweden)

    Stephani eDempsey

    2012-08-01

    Full Text Available Alcohol use disorders, like all drug addictions, involve a constellation of adaptive changes throughout the brain. Neural activity underlying changes in the rewarding properties of alcohol reflect changes in dopamine transmission in mesolimbic and nigrostriatal pathways and these effects are modulated by endogenous opioids such as b-Endorphin. In order to study the role of b-Endorphin in the development of locomotor sensitization to repeated EtOH exposure, we tested transgenic mice that vary in their capacity to synthesize this peptide as a result of constitutive modification of the Pomc gene. Our results indicate that mice deficient in b-Endorphin show attenuated locomotor activation following an acute injection of EtOH (2 g/kg and, in contrast to wildtype mice, fail to demonstrate locomotor sensitization after 12 days of repeated EtOH injections. These data support the idea that b-Endorphin modulates the locomotor effects of EtOH and contributes to the neuroadaptive changes associated with chronic use.

  13. Development and functional organization of spinal locomotor circuits

    DEFF Research Database (Denmark)

    Kiehn, Ole

    2011-01-01

    The coordination and timing of muscle activities during rhythmic movements, like walking and swimming, are generated by intrinsic spinal motor circuits. Such locomotor networks are operational early in development and are found in all vertebrates. This review outlines and compares recent advances...

  14. A Model of Locomotor-Respiratory Coupling in Quadrupeds

    Science.gov (United States)

    Giuliodori,, Mauricio J.; Lujan, Heidi L.; Briggs, Whitney S.; DiCarlo, Stephen E.

    2009-01-01

    Locomotion and respiration are not independent phenomena in running mammals because locomotion and respiration both rely on cyclic movements of the ribs, sternum, and associated musculature. Thus, constraints are imposed on locomotor and respiratory function by virtue of their linkage. Specifically, locomotion imposes mechanical constraints on…

  15. MRT of the locomotor system. 4. rev. and enl. ed.

    International Nuclear Information System (INIS)

    Vahlensieck, Martin; Reiser, Maximilian

    2015-01-01

    The book on MRT of the locomotor system covers the following topics: relevant NMT imaging techniques, spinal cord, shoulder, elbows, wrist and fingers, hip region, knee, lower leg - ankle - foot, temporomandibular joint, skeletal muscles, bone marrow, bone and soft tissue tumors, osteoporosis, sacroiliac joint, jaw and periodontium.

  16. Effects of nutmeg consumption on the open field locomotor activities ...

    African Journals Online (AJOL)

    ... was a steady significant difference (p < 0.05) in the behaviours of line crossing and walling. There was no much significant changes (P<0.05) in the behaviours of hinding, grooming and defeacation between the Treatments and Control groups of animals. Keywords: Nutmeg, Wistar rats, Open field, Locomotor activities ...

  17. Interpreting locomotor biomechanics from the morphology of human footprints.

    Science.gov (United States)

    Hatala, Kevin G; Wunderlich, Roshna E; Dingwall, Heather L; Richmond, Brian G

    2016-01-01

    Fossil hominin footprints offer unique direct windows to the locomotor behaviors of our ancestors. These data could allow a clearer understanding of the evolution of human locomotion by circumventing issues associated with indirect interpretations of habitual locomotor patterns from fossil skeletal material. However, before we can use fossil hominin footprints to understand better the evolution of human locomotion, we must first develop an understanding of how locomotor biomechanics are preserved in, and can be inferred from, footprint morphologies. In this experimental study, 41 habitually barefoot modern humans created footprints under controlled conditions in which variables related to locomotor biomechanics could be quantified. Measurements of regional topography (depth) were taken from 3D models of those footprints, and principal components analysis was used to identify orthogonal axes that described the largest proportions of topographic variance within the human experimental sample. Linear mixed effects models were used to quantify the influences of biomechanical variables on the first five principal axes of footprint topographic variation, thus providing new information on the biomechanical variables most evidently expressed in the morphology of human footprints. The footprint's overall depth was considered as a confounding variable, since biomechanics may be linked to the extent to which a substrate deforms. Three of five axes showed statistically significant relationships with variables related to both locomotor biomechanics and substrate displacement; one axis was influenced only by biomechanics and another only by the overall depth of the footprint. Principal axes of footprint morphological variation were significantly related to gait type (walking or running), kinematics of the hip and ankle joints and the distribution of pressure beneath the foot. These results provide the first quantitative framework for developing hypotheses regarding the

  18. The ventromedial hypothalamus oxytocin induces locomotor behavior regulated by estrogen.

    Science.gov (United States)

    Narita, Kazumi; Murata, Takuya; Matsuoka, Satoshi

    2016-10-01

    Our previous studies demonstrated that excitation of neurons in the rat ventromedial hypothalamus (VMH) induced locomotor activity. An oxytocin receptor (Oxtr) exists in the VMH and plays a role in regulating sexual behavior. However, the role of Oxtr in the VMH in locomotor activity is not clear. In this study we examined the roles of oxytocin in the VMH in running behavior, and also investigated the involvement of estrogen in this behavioral change. Microinjection of oxytocin into the VMH induced a dose-dependent increase in the running behavior in male rats. The oxytocin-induced running activity was inhibited by simultaneous injection of Oxtr-antagonist, (d(CH2)5(1), Try(Me)(2), Orn(8))-oxytocin. Oxytocin injection also induced running behavior in ovariectomized (OVX) female rats. Pretreatment of the OVX rats with estrogen augmented the oxytocin-induced running activity twofold, and increased the Oxtr mRNA in the VMH threefold. During the estrus cycle locomotor activity spontaneously increased in the dark period of proestrus. The Oxtr mRNA was up-regulated in the proestrus afternoon. Blockade of oxytocin neurotransmission by its antagonist before the onset of the dark period of proestrus decreased the following nocturnal locomotor activity. These findings demonstrate that Oxtr in the VMH is involved in the induction of running behavior and that estrogen facilitates this effect by means of Oxtr up-regulation, suggesting the involvement of oxytocin in the locomotor activity of proestrus female rats. Copyright © 2016 Elsevier Inc. All rights reserved.

  19. "The Strategic Effects of Firm Sizes and Dynamic Capabilities on Overseas Operations: A Case-based Comparison of Toyota and Mitsubishi in Thailand and Australia" (in Japanese)

    OpenAIRE

    Takahiro Fujimoto; Shinya Orihashi

    2002-01-01

    In international business, much attention has been directed to the international expansion of firms based on their use of resources and competitive capabilities that have been built up in a home country to create a competitive advantage over host-country firms. More recently, the organizational capabilities and competitive advantages of Japanese manufacturing firms in general (in autos, electronics, etc.) have been analyzed as important factors in the establishment of overseas transplants. Th...

  20. "The Strategic Effects of Firm Sizes and Dynamic Capabilities on Overseas Operations: A Case-based Comparison of Toyota and Mitsubishi in Thailand and Australia"

    OpenAIRE

    Takahiro Fujimoto; Shinya Orihashi

    2002-01-01

    In international business, much attention has been directed to the international expansion of firms based on their use of resources and competitive capabilities that have been built up in a home country to create a competitive advantage over host-country firms. More recently, the organizational capabilities and competitive advantages of Japanese manufacturing firms in general (in autos, electronics, etc.) have been analyzed as important factors in the establishment of overseas transplants. Th...

  1. [The formation of the self-maintenance skills in the pre-school children presenting with locomotor and coordination disorders].

    Science.gov (United States)

    Poletaeva-Dubrovina, N A; Burkova, A M

    2016-01-01

    The Ministry of Health of the Russian Federation acknowledges the sharp rise in the prevalence of congenital malformation in this country during the past 30 years. In 2010-2011, this pathology was estimated to occur in 3% of the children. It includes a variety of locomotor and coordination disorders of which the most widespread are infantile cerebral paralysis, ataxia, consequences of perinatal lesions of the central nervous system, etc. This article contains a detailed description of these locomotor and coordination disorders. The objective of the present work was to elaborate and evaluate the program for the formation of the self-maintenance skills in the pre-school children presenting with locomotor and coordination disorders under conditions of family guidance and education. The study was carried out from September 2013 till May 2014 based at MUP DOD "Semeiny klub Nadezhda" ("The Hope Family Club", Municipal unitary facility for children's additional education) and supported by B.N. El'tsin Ural Federal University. It included 10 children suffering from locomotor and coordination disorders of different severity and members of their families. The following methods were used: the self-service skills scorecard , monitoring formation of the motor skills, and Wilcoxon's T-test. The use of the program based on the cooperation with the children's families allowed to achieve positive dynamics in the patients' conditions. Moreover, 30% of them acquired the full scope of the self-maintenance skills. The most pronounced changes in the motor abilities were apparent in the movements of the upper and lower extremitis, walking, and motion in space. The proposed program for the formation of the self-maintenance skills in the pre-school children presenting with locomotor and coordination disorders proved to be highly efficacious. The study has demonstrated the importance of the parents' involvement in the process of formation of the self-maintenance skills and motor abilities

  2. Distinct sets of locomotor modules control the speed and modes of human locomotion

    Science.gov (United States)

    Yokoyama, Hikaru; Ogawa, Tetsuya; Kawashima, Noritaka; Shinya, Masahiro; Nakazawa, Kimitaka

    2016-01-01

    Although recent vertebrate studies have revealed that different spinal networks are recruited in locomotor mode- and speed-dependent manners, it is unknown whether humans share similar neural mechanisms. Here, we tested whether speed- and mode-dependence in the recruitment of human locomotor networks exists or not by statistically extracting locomotor networks. From electromyographic activity during walking and running over a wide speed range, locomotor modules generating basic patterns of muscle activities were extracted using non-negative matrix factorization. The results showed that the number of modules changed depending on the modes and speeds. Different combinations of modules were extracted during walking and running, and at different speeds even during the same locomotor mode. These results strongly suggest that, in humans, different spinal locomotor networks are recruited while walking and running, and even in the same locomotor mode different networks are probably recruited at different speeds. PMID:27805015

  3. FES-assisted Cycling Improves Aerobic Capacity and Locomotor Function Postcerebrovascular Accident.

    Science.gov (United States)

    Aaron, Stacey E; Vanderwerker, Catherine J; Embry, Aaron E; Newton, Jennifer H; Lee, Samuel C K; Gregory, Chris M

    2018-03-01

    After a cerebrovascular accident (CVA) aerobic deconditioning contributes to diminished physical function. Functional electrical stimulation (FES)-assisted cycling is a promising exercise paradigm designed to target both aerobic capacity and locomotor function. This pilot study aimed to evaluate the effects of an FES-assisted cycling intervention on aerobic capacity and locomotor function in individuals post-CVA. Eleven individuals with chronic (>6 months) post-CVA hemiparesis completed an 8-wk (three times per week; 24 sessions) progressive FES-assisted cycling intervention. V˙O2peak, self-selected, and fastest comfortable walking speeds, gait, and pedaling symmetry, 6-min walk test (6MWT), balance, dynamic gait movements, and health status were measured at baseline and posttraining. Functional electrical stimulation-assisted cycling significantly improved V˙O2peak (12%, P = 0.006), self-selected walking speed (SSWS, 0.05 ± 0.1 m·s, P = 0.04), Activities-specific Balance Confidence scale score (12.75 ± 17.4, P = 0.04), Berg Balance Scale score (3.91 ± 4.2, P = 0.016), Dynamic Gait Index score (1.64 ± 1.4, P = 0.016), and Stroke Impact Scale participation/role domain score (12.74 ± 16.7, P = 0.027). Additionally, pedal symmetry, represented by the paretic limb contribution to pedaling (paretic pedaling ratio [PPR]) significantly improved (10.09% ± 9.0%, P = 0.016). Although step length symmetry (paretic step ratio [PSR]) did improve, these changes were not statistically significant (-0.05% ± 0.1%, P = 0.09). Exploratory correlations showed moderate association between change in SSWS and 6-min walk test (r = 0.74), and moderate/strong negative association between change in PPR and PSR. These results support FES-assisted cycling as a means to improve both aerobic capacity and locomotor function. Improvements in SSWS, balance, dynamic walking movements, and participation in familial and societal roles are important targets for rehabilitation of individuals

  4. 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.

  5. A wider pelvis does not increase locomotor cost in humans, with implications for the evolution of childbirth.

    Directory of Open Access Journals (Sweden)

    Anna G Warrener

    Full Text Available The shape of the human female pelvis is thought to reflect an evolutionary trade-off between two competing demands: a pelvis wide enough to permit the birth of large-brained infants, and narrow enough for efficient bipedal locomotion. This trade-off, known as the obstetrical dilemma, is invoked to explain the relative difficulty of human childbirth and differences in locomotor performance between men and women. The basis for the obstetrical dilemma is a standard static biomechanical model that predicts wider pelves in females increase the metabolic cost of locomotion by decreasing the effective mechanical advantage of the hip abductor muscles for pelvic stabilization during the single-leg support phase of walking and running, requiring these muscles to produce more force. Here we experimentally test this model against a more accurate dynamic model of hip abductor mechanics in men and women. The results show that pelvic width does not predict hip abductor mechanics or locomotor cost in either women or men, and that women and men are equally efficient at both walking and running. Since a wider birth canal does not increase a woman's locomotor cost, and because selection for successful birthing must be strong, other factors affecting maternal pelvic and fetal size should be investigated in order to help explain the prevalence of birth complications caused by a neonate too large to fit through the birth canal.

  6. Locomotor Behavior of Chickens Anticipating Incline Walking

    Directory of Open Access Journals (Sweden)

    Chantal LeBlanc

    2018-01-01

    Full Text Available Keel bone damage (KBD is prevalent in hens raised for egg production, and ramps between different tiers in aviaries have potential to reduce the frequency of falls resulting in KBD. Effective use of ramps requires modulation of locomotion in anticipation of the incline. Inadequate adaptive locomotion may be one explanation why domestic layer hens (Gallus gallus domesticus exhibit high rates of KBD. To improve understanding of the capacity of hens to modulate their locomotion in anticipation of climbing, we measured the effects of incline angle upon the mechanics of the preparatory step before ascending a ramp. Because the energetic challenge of climbing increases with slope, we predicted that as angle of incline increased, birds during foot contact with the ground before starting to climb would increase their peak force and duration of contact and reduce variation in center of pressure (COP under their foot. We tested 20 female domestic chickens on ramp inclines at slopes of +0°, +40°, and +70° when birds were 17, 21, 26, 31, and 36 weeks of age. There were significantly higher vertical peak ground reaction forces in preparation at the steepest slope, and ground contact time increased significantly with each increase in ramp angle. Effects upon variation in COP were not apparent; likewise, effects of limb length, age, body mass were not significant. Our results reveal that domestic chickens are capable of modulating their locomotion in response to incline angle.

  7. Usability evaluation of a locomotor therapy device considering different strategies

    Directory of Open Access Journals (Sweden)

    Langthaler Sonja

    2016-09-01

    Full Text Available Usability of medical devices is one of the main determining factors in preventing use errors in treatment and strongly correlates to patient safety and quality of treatment. This thesis demonstrates the usability testing and evaluation of a prototype for locomotor therapy of infants. Therefore, based on the normative requirements of the EN 62366, a concept combined of evaluation procedures and assessing methods was created to enable extensive testing and analysis of the different aspects of usability. On the basis of gathered information weak points were identified and appropriate measures were presented to increase the usability and operating safety of the locomotor prototype. The overall outcome showed an usability value of 77.4% and an evaluation score of 6.99, which can be interpreted as “satisfactory”.

  8. The peacock train does not handicap cursorial locomotor performance

    Science.gov (United States)

    Thavarajah, Nathan K.; Tickle, Peter G.; Nudds, Robert L.; Codd, Jonathan R.

    2016-01-01

    Exaggerated traits, like the peacock train, are recognized as classic examples of sexual selection. The evolution of sexual traits is often considered paradoxical as, although they enhance reproductive success, they are widely presumed to hinder movement and survival. Many exaggerated traits represent an additional mechanical load that must be carried by the animal and therefore may influence the metabolic cost of locomotion and constrain locomotor performance. Here we conducted respirometry experiments on peacocks and demonstrate that the exaggerated sexually selected train does not compromise locomotor performance in terms of the metabolic cost of locomotion and its kinematics. Indeed, peacocks with trains had a lower absolute and mass specific metabolic cost of locomotion. Our findings suggest that adaptations that mitigate any costs associated with exaggerated morphology are central in the evolution of sexually selected traits. PMID:27805067

  9. Structural attributes contributing to locomotor performance in the ostrich

    OpenAIRE

    Schaller, Nina U.

    2008-01-01

    As the fastest long-endurance runner, the bipedal ostrich (Struthio camelus) was selected as a prime model organism to investigate the physical attributes underlying this advanced locomotor performance. A specific integrative approach combining morphological, morphometric, kinematic and pedobarographic methods was developed. The comparative morphometric analysis of the hind limbs of all ratite species revealed that leg segment ratios in the ostrich are the most specialised for efficient locom...

  10. Muscle Spindles and Locomotor Control-An Unrecognized Falls Determinant?

    OpenAIRE

    Marks Ray

    2015-01-01

    BACKGROUND: Historically, evidence muscle spindles might be involved in locomotion was provided by their presence in tetrapod antigravity muscles associated with posture and locomotion. Later, Brodal (1962) noted muscle spindles in all muscles of locomotion. To unravel the complexity of the muscle spindle and its role in human locomotor control many investigators have since conducted lesion and/or anaesthesia studies in subhuman species and human contexts. QUESTIONS: How ...

  11. Locomotor Sub-functions for Control of Assistive Wearable Robots

    OpenAIRE

    Sharbafi, Maziar A.; Seyfarth, Andre; Zhao, Guoping

    2017-01-01

    A primary goal of comparative biomechanics is to understand the fundamental physics of locomotion within an evolutionary context. Such an understanding of legged locomotion results in a transition from copying nature to borrowing strategies for interacting with the physical world regarding design and control of bio-inspired legged robots or robotic assistive devices. Inspired from nature, legged locomotion can be composed of three locomotor sub-functions, which are intrinsically interrelated:...

  12. Locomotor therapy with extended-release crystalline glucocorticoids

    Directory of Open Access Journals (Sweden)

    Vladimir Vasilyevich Badokin

    2013-01-01

    Full Text Available Topical glucocorticoid (GC therapy for locomotor diseases is an extremely important component of a comprehensive program to treat inflammatory and, to a lesser extent, degenerative diseases. It reduces the time of hospitalization by 5—10 days in this category of patients, has a prompt and potent anti-inflammatory effect, and shows predictable efficiency. This therapy shows good tolerability and high safety and prevents serious adverse reactions to GC treatment.

  13. Limitations imposed by wearing armour on Medieval soldiers' locomotor performance

    OpenAIRE

    Askew, Graham N.; Formenti, Federico; Minetti, Alberto E.

    2011-01-01

    In Medieval Europe, soldiers wore steel plate armour for protection during warfare. Armour design reflected a trade-off between protection and mobility it offered the wearer. By the fifteenth century, a typical suit of field armour weighed between 30 and 50 kg and was distributed over the entire body. How much wearing armour affected Medieval soldiers' locomotor energetics and biomechanics is unknown. We investigated the mechanics and the energetic cost of locomotion in armour, and determined...

  14. Vestibular lesion-induced developmental plasticity in spinal locomotor networks during Xenopus laevis metamorphosis.

    Science.gov (United States)

    Beyeler, Anna; Rao, Guillaume; Ladepeche, Laurent; Jacques, André; Simmers, John; Le Ray, Didier

    2013-01-01

    During frog metamorphosis, the vestibular sensory system remains unchanged, while spinal motor networks undergo a massive restructuring associated with the transition from the larval to adult biomechanical system. We investigated in Xenopus laevis the impact of a pre- (tadpole stage) or post-metamorphosis (juvenile stage) unilateral labyrinthectomy (UL) on young adult swimming performance and underlying spinal locomotor circuitry. The acute disruptive effects on locomotion were similar in both tadpoles and juvenile frogs. However, animals that had metamorphosed with a preceding UL expressed restored swimming behavior at the juvenile stage, whereas animals lesioned after metamorphosis never recovered. Whilst kinematic and electrophysiological analyses of the propulsive system showed no significant differences in either juvenile group, a 3D biomechanical simulation suggested that an asymmetry in the dynamic control of posture during swimming could account for the behavioral restoration observed in animals that had been labyrinthectomized before metamorphosis. This hypothesis was subsequently supported by in vivo electromyography during free swimming and in vitro recordings from isolated brainstem/spinal cord preparations. Specifically, animals lesioned prior to metamorphosis at the larval stage exhibited an asymmetrical propulsion/posture coupling as a post-metamorphic young adult. This developmental alteration was accompanied by an ipsilesional decrease in propriospinal coordination that is normally established in strict left-right symmetry during metamorphosis in order to synchronize dorsal trunk muscle contractions with bilateral hindlimb extensions in the swimming adult. Our data thus suggest that a disequilibrium in descending vestibulospinal information during Xenopus metamorphosis leads to an altered assembly of adult spinal locomotor circuitry. This in turn enables an adaptive compensation for the dynamic postural asymmetry induced by the vestibular imbalance

  15. Rights, goals, and capabilities

    NARCIS (Netherlands)

    van Hees, M.V.B.P.M

    This article analyses the relationship between rights and capabilities in order to get a better grasp of the kind of consequentialism that the capability theory represents. Capability rights have been defined as rights that have a capability as their object (rights to capabilities). Such a

  16. Ankle voluntary movement enhancement following robotic-assisted locomotor training in spinal cord injury.

    Science.gov (United States)

    Varoqui, Deborah; Niu, Xun; Mirbagheri, Mehdi M

    2014-03-31

    In incomplete spinal cord injury (iSCI), sensorimotor impairments result in severe limitations to ambulation. To improve walking capacity, physical therapies using robotic-assisted locomotor devices, such as the Lokomat, have been developed. Following locomotor training, an improvement in gait capabilities-characterized by increases in the over-ground walking speed and endurance-is generally observed in patients. To better understand the mechanisms underlying these improvements, we studied the effects of Lokomat training on impaired ankle voluntary movement, known to be an important limiting factor in gait for iSCI patients. Fifteen chronic iSCI subjects performed twelve 1-hour sessions of Lokomat training over the course of a month. The voluntary movement was qualified by measuring active range of motion, maximal velocity peak and trajectory smoothness for the spastic ankle during a movement from full plantar-flexion (PF) to full dorsi-flexion (DF) at the patient's maximum speed. Dorsi- and plantar-flexor muscle strength was quantified by isometric maximal voluntary contraction (MVC). Clinical assessments were also performed using the Timed Up and Go (TUG), the 10-meter walk (10MWT) and the 6-minute walk (6MWT) tests. All evaluations were performed both before and after the training and were compared to a control group of fifteen iSCI patients. After the Lokomat training, the active range of motion, the maximal velocity, and the movement smoothness were significantly improved in the voluntary movement. Patients also exhibited an improvement in the MVC for their ankle dorsi- and plantar-flexor muscles. In terms of functional activity, we observed an enhancement in the mobility (TUG) and the over-ground gait velocity (10MWT) with training. Correlation tests indicated a significant relationship between ankle voluntary movement performance and the walking clinical assessments. The improvements of the kinematic and kinetic parameters of the ankle voluntary movement

  17. Using Tests Designed to Measure Individual Sensorimotor Subsystem Perfomance to Predict Locomotor Adaptability

    Science.gov (United States)

    Peters, B. T.; Caldwell, E. E.; Batson, C. D.; Guined, J. R.; DeDios, Y. E.; Stepanyan, V.; Gadd, N. E.; Szecsy, D. L.; Mulavara, A. P.; Seidler, R. D.; hide

    2014-01-01

    Astronauts experience sensorimotor disturbances during the initial exposure to microgravity and during the readapation phase following a return to a gravitational environment. These alterations may lead to disruption in the ability to perform mission critical functions during and after these gravitational transitions. Astronauts show significant inter-subject variation in adaptive capability following gravitational transitions. The way each individual's brain synthesizes the available visual, vestibular and somatosensory information is likely the basis for much of the variation. Identifying the presence of biases in each person's use of information available from these sensorimotor subsystems and relating it to their ability to adapt to a novel locomotor task will allow us to customize a training program designed to enhance sensorimotor adaptability. Eight tests are being used to measure sensorimotor subsystem performance. Three of these use measures of body sway to characterize balance during varying sensorimotor challenges. The effect of vision is assessed by repeating conditions with eyes open and eyes closed. Standing on foam, or on a support surface that pitches to maintain a constant ankle angle provide somatosensory challenges. Information from the vestibular system is isolated when vision is removed and the support surface is compromised, and it is challenged when the tasks are done while the head is in motion. The integration and dominance of visual information is assessed in three additional tests. The Rod & Frame Test measures the degree to which a subject's perception of the visual vertical is affected by the orientation of a tilted frame in the periphery. Locomotor visual dependence is determined by assessing how much an oscillating virtual visual world affects a treadmill-walking subject. In the third of the visual manipulation tests, subjects walk an obstacle course while wearing up-down reversing prisms. The two remaining tests include direct

  18. Training Enhances Both Locomotor and Cognitive Adaptability to a Novel Sensory Environment

    Science.gov (United States)

    Bloomberg, J. J.; Peters, B. T.; Mulavara, A. P.; Brady, R. A.; Batson, C. D.; Ploutz-Snyder, R. J.; Cohen, H. S.

    2010-01-01

    During adaptation to novel gravitational environments, sensorimotor disturbances have the potential to disrupt the ability of astronauts to perform required mission tasks. The goal of this project is to develop a sensorimotor adaptability (SA) training program to facilitate rapid adaptation. We have developed a unique training system comprised of a treadmill placed on a motion-base facing a virtual visual scene that provides an unstable walking surface combined with incongruent visual flow designed to enhance sensorimotor adaptability. The goal of our present study was to determine if SA training improved both the locomotor and cognitive responses to a novel sensory environment and to quantify the extent to which training would be retained. Methods: Twenty subjects (10 training, 10 control) completed three, 30-minute training sessions during which they walked on the treadmill while receiving discordant support surface and visual input. Control subjects walked on the treadmill but did not receive any support surface or visual alterations. To determine the efficacy of training all subjects performed the Transfer Test upon completion of training. For this test, subjects were exposed to novel visual flow and support surface movement, not previously experienced during training. The Transfer Test was performed 20 minutes, 1 week, 1, 3 and 6 months after the final training session. Stride frequency, auditory reaction time, and heart rate data were collected as measures of postural stability, cognitive effort and anxiety, respectively. Results: Using mixed effects regression methods we determined that subjects who received SA training showed less alterations in stride frequency, auditory reaction time and heart rate compared to controls. Conclusion: Subjects who received SA training improved performance across a number of modalities including enhanced locomotor function, increased multi-tasking capability and reduced anxiety during adaptation to novel discordant sensory

  19. Method for determining dynamic short circuit withstand capability of installations in meshed cable MV-networks, during switch on to a fault

    NARCIS (Netherlands)

    Parabirsing, E.N.; Coster, E.J.; Goerdin, S.A.V.

    2013-01-01

    tedin is the Distribution Grid Operator in the western part of the Netherlands and is known to be a "slim network operator" which means that it is only responsible for managing the gas and electricity networks. In this paper a method will be described with which Stedin proved that the dynamic short

  20. Human neural stem cells differentiate and promote locomotor recovery in an early chronic spinal cord injury NOD-scid mouse model.

    Directory of Open Access Journals (Sweden)

    Desirée L Salazar

    2010-08-01

    Full Text Available Traumatic spinal cord injury (SCI results in partial or complete paralysis and is characterized by a loss of neurons and oligodendrocytes, axonal injury, and demyelination/dysmyelination of spared axons. Approximately 1,250,000 individuals have chronic SCI in the U.S.; therefore treatment in the chronic stages is highly clinically relevant. Human neural stem cells (hCNS-SCns were prospectively isolated based on fluorescence-activated cell sorting for a CD133(+ and CD24(-/lo population from fetal brain, grown as neurospheres, and lineage restricted to generate neurons, oligodendrocytes and astrocytes. hCNS-SCns have recently been transplanted sub-acutely following spinal cord injury and found to promote improved locomotor recovery. We tested the ability of hCNS-SCns transplanted 30 days post SCI to survive, differentiate, migrate, and promote improved locomotor recovery.hCNS-SCns were transplanted into immunodeficient NOD-scid mice 30 days post spinal cord contusion injury. hCNS-SCns transplanted mice demonstrated significantly improved locomotor recovery compared to vehicle controls using open field locomotor testing and CatWalk gait analysis. Transplanted hCNS-SCns exhibited long-term engraftment, migration, limited proliferation, and differentiation predominantly to oligodendrocytes and neurons. Astrocytic differentiation was rare and mice did not exhibit mechanical allodynia. Furthermore, differentiated hCNS-SCns integrated with the host as demonstrated by co-localization of human cytoplasm with discrete staining for the paranodal marker contactin-associated protein.The results suggest that hCNS-SCns are capable of surviving, differentiating, and promoting improved locomotor recovery when transplanted into an early chronic injury microenvironment. These data suggest that hCNS-SCns transplantation has efficacy in an early chronic SCI setting and thus expands the "window of opportunity" for intervention.

  1. An Integrated Gait and Balance Analysis System to Define Human Locomotor Control

    Science.gov (United States)

    2016-04-29

    test hypotheses they developed about how people walk. An Integrated Gait and Balance Analysis System to define Human Locomotor Control W911NF-14-R-0009...An Integrated Gait and Balance Analysis System to Define Human Locomotor Control Walking is a complicated task that requires the motor coordination...Gait and Balance Analysis System to Define Human Locomotor Control Report Title Walking is a complicated task that requires the motor coordination across

  2. Mobile Test Capabilities

    Data.gov (United States)

    Federal Laboratory Consortium — The Electrical Power Mobile Test capabilities are utilized to conduct electrical power quality testing on aircraft and helicopters. This capability allows that the...

  3. Locomotor activity: A distinctive index in morphine self-administration in rats

    Science.gov (United States)

    Kong, Qingyao

    2017-01-01

    Self-administration of addictive drugs is a widely used tool for studying behavioral, neurobiological, and genetic factors in addiction. However, how locomotor activity is affected during self-administration of addictive drugs has not been extensively studied. In our present study, we tested the locomotor activity levels during acquisition, extinction and reinstatement of morphine self-administration in rats. We found that compared with saline self-administration (SA), rats that trained with morphine SA had higher locomotor activity. Rats that successfully acquired SA also showed higher locomotor activity than rats that failed in acquiring SA. Moreover, locomotor activity was correlated with the number of drug infusions but not with the number of inactive pokes. We also tested the locomotor activity in the extinction and the morphine-primed reinstatement session. Interestingly, we found that in the first extinction session, although the number of active pokes did not change, the locomotor activity was significantly lower than in the last acquisition session, and this decrease can be maintained for at least six days. Finally, morphine priming enhanced the locomotor activity during the reinstatement test, regardless of if the active pokes were significantly increased or not. Our results clearly suggest that locomotor activity, which may reflect the pharmacological effects of morphine, is different from drug seeking behavior and is a distinctive index in drug self-administration. PMID:28380023

  4. Locomotor activity: A distinctive index in morphine self-administration in rats.

    Science.gov (United States)

    Zhang, Jian-Jun; Kong, Qingyao

    2017-01-01

    Self-administration of addictive drugs is a widely used tool for studying behavioral, neurobiological, and genetic factors in addiction. However, how locomotor activity is affected during self-administration of addictive drugs has not been extensively studied. In our present study, we tested the locomotor activity levels during acquisition, extinction and reinstatement of morphine self-administration in rats. We found that compared with saline self-administration (SA), rats that trained with morphine SA had higher locomotor activity. Rats that successfully acquired SA also showed higher locomotor activity than rats that failed in acquiring SA. Moreover, locomotor activity was correlated with the number of drug infusions but not with the number of inactive pokes. We also tested the locomotor activity in the extinction and the morphine-primed reinstatement session. Interestingly, we found that in the first extinction session, although the number of active pokes did not change, the locomotor activity was significantly lower than in the last acquisition session, and this decrease can be maintained for at least six days. Finally, morphine priming enhanced the locomotor activity during the reinstatement test, regardless of if the active pokes were significantly increased or not. Our results clearly suggest that locomotor activity, which may reflect the pharmacological effects of morphine, is different from drug seeking behavior and is a distinctive index in drug self-administration.

  5. Sound stabilizes locomotor-respiratory coupling and reduces energy cost.

    Directory of Open Access Journals (Sweden)

    Charles P Hoffmann

    Full Text Available A natural synchronization between locomotor and respiratory systems is known to exist for various species and various forms of locomotion. This Locomotor-Respiratory Coupling (LRC is fundamental for the energy transfer between the two subsystems during long duration exercise and originates from mechanical and neurological interactions. Different methodologies have been used to compute LRC, giving rise to various and often diverging results in terms of synchronization, (de-stabilization via information, and associated energy cost. In this article, the theory of nonlinear-coupled oscillators was adopted to characterize LRC, through the model of the sine circle map, and tested it in the context of cycling. Our specific focus was the sound-induced stabilization of LRC and its associated change in energy consumption. In our experimental study, participants were instructed during a cycling exercise to synchronize either their respiration or their pedaling rate with an external auditory stimulus whose rhythm corresponded to their individual preferential breathing or cycling frequencies. Results showed a significant reduction in energy expenditure with auditory stimulation, accompanied by a stabilization of LRC. The sound-induced effect was asymmetrical, with a better stabilizing influence of the metronome on the locomotor system than on the respiratory system. A modification of the respiratory frequency was indeed observed when participants cycled in synchrony with the tone, leading to a transition toward more stable frequency ratios as predicted by the sine circle map. In addition to the classical mechanical and neurological origins of LRC, here we demonstrated using the sine circle map model that information plays an important modulatory role of the synchronization, and has global energetic consequences.

  6. Locomotor skills and balance strategies in adolescents idiopathic scoliosis.

    Science.gov (United States)

    Mallau, Sophie; Bollini, Gérard; Jouve, Jean-Luc; Assaiante, Christine

    2007-01-01

    Locomotor balance control assessment was performed to study the effect of idiopathic scoliosis on head-trunk coordination in 17 patients with adolescent idiopathic scoliosis (AIS) and 16 control subjects. The aim of this study was to explore the functional effects of structural spinal deformations like idiopathic scoliosis on the balance strategies used during locomotion. Up to now, the repercussion of the idiopathic scoliosis on head-trunk coordination and balance strategies during locomotion is relatively unknown. Seventeen patients with AIS (mean age 14 years 3 months, 10 degrees 30 degrees) and 16 control subjects (mean age 14 years 1 month) were tested during various locomotor tasks: walking on the ground, walking on a line, and walking on a beam. Balance control was examined in terms of rotation about the vertical axis (yaw) and on a frontal plane (roll). Kinematics of foot, pelvis, trunk, shoulder, and head rotations were measured with an automatic optical TV image processor in order to calculate angular dispersions and segmental stabilizations. Decreasing the walking speed is the main adaptive strategy used in response to balance problems in control subjects as well as patients with AIS. However, patients with AIS performed walking tasks more slowly than normal subjects (around 15%). Moreover, the pelvic stabilization is preserved, despite the structural changes affecting the spine. Lastly, the biomechanical defect resulting from idiopathic scoliosis mainly affects the yaw head stabilization during locomotion. Patients with AIS show substantial similarities with control subjects in adaptive strategies relative to locomotor velocity as well as balance control based on segmental stabilization. In contrast, the loss of the yaw head stabilization strategies, mainly based on the use of vestibular information, probably reflects the presence of vestibular deficits in the patients with AIS.

  7. Low dose radiation enhances the Locomotor activity of D. melanogaster

    Energy Technology Data Exchange (ETDEWEB)

    Seong, Ki Moon; Lee, Buyng Sub; Nam Seon Young; Kim, Ji Young; Yang, Kwang Hee; Choi, Tae In; Kim, Cha Soon [Radiation Effect Research Team, Radiation Health Research Institute, Korea Hydro and Nuclear Power Co., Ltd., Gyeongju (Korea, Republic of)

    2013-04-15

    Mild stresses at low level including radiation can induce the beneficial effects in many vertebrate and invertebrate species. However, a large amount of studies in radiation biology have focused on the detrimental effects of high dose radiation (HDR) such as the increased incidence of cancers and developmental diseases. Low dose radiation (LDR) induces biologically favorable effects in diverse fields, for example, cancer development, genomic instability, immune response, and longevity. Our previous data indicated that LDR promotes cells proliferation of which degree is not much but significant, and microarray data explained that LDR irradiated fruit flies showing the augmented immunity significantly changed the program for gene expression of many genes in Gene Ontology (GO) categories related to metabolic process. Metabolic process in development one of major contributors in organism growth, interbreeding, motility, and aging. Therefore, it is valuable to examine whether LDR change the physiological parameters related to metabolism, and how LDR regulates the metabolism in D. melanogaster. In this study, to investigate that LDR influences change of the metabolism, a representative parameter, locomotor activity. In addition, the activation of several cellular signal molecules was determined to investigate the specific molecular mechanism of LDR effects on the metabolism. We explored whether ionizing radiation affects the motility activity. We performed the RING assays to evaluate the locomotor activity, a representative parameter presenting motility of fruit flies. HDR dramatically decreased the motor activity of irradiated flies. Surprisingly, the irradiated flies at low dose radiation in both acute and chronic showed the significantly increased locomotor activity, compared to non-irradiated flies. Irradiation would induce change of the several signal pathways for flies to respond to it. The activation of some proteins involved in the cells proliferation and stress

  8. Sex differences in locomotor effects of morphine in the rat

    OpenAIRE

    Craft, Rebecca M.; Clark, James L.; Hart, Stephen P.; Pinckney, Megan K.

    2006-01-01

    Sex differences in reinforcing, analgesic and other effects of opioids have been demonstrated; however, the extent to which sex differences in motoric effects of opioids contribute to apparent sex differences in their primary effects is not known. The goal of this study was to compare the effects of the prototypic mu opioid agonist morphine on locomotor activity in male vs. female rats. Saline or morphine (1-10 mg/kg) was administered s.c. to adult Sprague-Dawley rats, which were placed into ...

  9. Designing Functional Clothes for Persons with Locomotor Disabilities

    Directory of Open Access Journals (Sweden)

    Curteza Antonela

    2014-12-01

    Full Text Available The life quality improvement issue is a problem of national and international interest. This acquires total different values when it is to refer to a series of disadvantaged categories, that is the persons with locomotor disabilities. It is an inevitable social responsibility to create equal opportunities for disabled people, to prevent any intentional or unintentional discrimination that they face and apply positive discrimination if necessary to improve their living standards and to let them have an equal share from social development as productive individuals of society.

  10. Digestive and locomotor capacity show opposing responses to changing food availability in an ambush predatory fish.

    Science.gov (United States)

    Fu, Shi-Jian; Peng, Jing; Killen, Shaun S

    2018-06-14

    Metabolic rates vary widely within species, but little is known about how variation in the 'floor' [i.e. standard metabolic rate (SMR) in ectotherms] and 'ceiling' [maximum metabolic rate (MMR)] for an individual's aerobic scope (AS) are linked with digestive and locomotor function. Any links among metabolic traits and aspects of physiological performance may also be modulated by fluctuations in food availability. This study followed changes in SMR, MMR, and digestive and locomotor capacity in southern catfish ( Silurus meridionalis ) throughout 15 days of food deprivation and 15 days of refeeding. Individuals downregulated SMR during food deprivation and showed only a 10% body mass decrease during this time. Whereas critical swim speed ( U crit ) was robust to food deprivation, digestive function decreased after fasting with a reduced peak oxygen uptake during specific dynamic action (SDA) and prolonged SDA duration. During refeeding, individuals displayed rapid growth and digestive function recovered to pre-fasting levels. However, refed fish showed a lower U crit than would be expected for their increased body length and in comparison to measures at the start of the study. Reduced swimming ability may be a consequence of compensatory growth: growth rate was negatively correlated with changes in U crit during refeeding. Southern catfish downregulate digestive function to reduce energy expenditure during food deprivation, but regain digestive capacity during refeeding, potentially at the cost of decreased swimming performance. The plasticity of maintenance requirements suggests that SMR is a key fitness trait for in this ambush predator. Shifts in trait correlations with food availability suggest that the potential for correlated selection may depend on context. © 2018. Published by The Company of Biologists Ltd.

  11. Run don't walk: locomotor performance of geckos on wet substrates.

    Science.gov (United States)

    Stark, Alyssa Y; Ohlemacher, Jocelyn; Knight, Ashley; Niewiarowski, Peter H

    2015-08-01

    The gecko adhesive system has been under particular scrutiny for over a decade, as the field has recently attracted attention for its application to bio-inspired design. However, little is known about how the adhesive system behaves in ecologically relevant conditions. Geckos inhabit a variety of environments, many of which are characterized by high temperature, humidity and rain. The van der Waals-based gecko adhesive system should be particularly challenged by wet substrates because water can disrupt the intimate contact necessary for adhesion. While a few previous studies have focused on the clinging ability of geckos on wet substrates, we tested a dynamic performance characteristic, sprint velocity. To better understand how substrate wettability and running orientation affect locomotor performance of multiple species on wet substrates, we measured average sprint velocity of five species of gecko on substrates that were either hydrophilic or intermediately wetting and oriented either vertically or horizontally. Surprisingly, we found no indication that wet substrates impact average sprint velocity over 1 m, and rather, in some species, sprint velocity was increased on wet substrates rather than reduced. When investigating physical characteristics and behavior that may be associated with running on wet substrates, such as total number of stops, slips and wet toes at the completion of a race, we found that there may be habitat-related differences between some species. Our results show that in general, unlike clinging and walking, geckos running along wet substrates suffer no significant loss in locomotor performance over short distances. © 2015. Published by The Company of Biologists Ltd.

  12. Differential housing and novelty response: Protection and risk from locomotor sensitization.

    Science.gov (United States)

    Garcia, Erik J; Haddon, Tara N; Saucier, Donald A; Cain, Mary E

    2017-03-01

    High novelty seeking increases the risk for drug experimentation and locomotor sensitization. Locomotor sensitization to psychostimulants is thought to reflect neurological adaptations that promote the transition to compulsive drug taking. Rats reared in enrichment (EC) show less locomotor sensitization when compared to rats reared in isolation (IC) or standard conditions (SC). The current research study was designed to test if novelty response contributed locomotor sensitization and more importantly, if the different housing environments could change the novelty response to protect against the development of locomotor sensitization in both adolescence and adulthood. Experiment 1: rats were tested for their response to novelty using the inescapable novelty test (IEN) and pseudorandomly assigned to enriched (EC), isolated (IC), or standard (SC) housing conditions for 30days. After housing, they were tested with IEN. Rats were then administered amphetamine (0.5mg/kg) or saline and locomotor activity was measured followed by a sensitization test 14days later. Experiment 2: rats were tested in the IEN test early adulthood and given five administrations of amphetamine (0.3mg/kg) or saline and then either stayed in or switched housing environments for 30days. Rats were then re-tested in the IEN test in late adulthood and administered five more injections of their respective treatments and tested for locomotor sensitization. Results indicate that IC and SC increased the response to novelty. EC housing decreased locomotor response to amphetamine and saline, and SC housing increased the locomotor response to amphetamine. Mediation results indicated that the late adult novelty response fully mediates the locomotor response to amphetamine and saline, while the early adulthood novelty response did not. Differential housing changes novelty and amphetamine locomotor response. Novelty response is altered into adulthood and provides evidence that enrichment can be used to reduce

  13. Optimizing learning of a locomotor task: amplifying errors as needed.

    Science.gov (United States)

    Marchal-Crespo, Laura; López-Olóriz, Jorge; Jaeger, Lukas; Riener, Robert

    2014-01-01

    Research on motor learning has emphasized that errors drive motor adaptation. Thereby, several researchers have proposed robotic training strategies that amplify movement errors rather than decrease them. In this study, the effect of different robotic training strategies that amplify errors on learning a complex locomotor task was investigated. The experiment was conducted with a one degree-of freedom robotic stepper (MARCOS). Subjects were requested to actively coordinate their legs in a desired gait-like pattern in order to track a Lissajous figure presented on a visual display. Learning with three different training strategies was evaluated: (i) No perturbation: the robot follows the subjects' movement without applying any perturbation, (ii) Error amplification: existing errors were amplified with repulsive forces proportional to errors, (iii) Noise disturbance: errors were evoked with a randomly-varying force disturbance. Results showed that training without perturbations was especially suitable for a subset of initially less-skilled subjects, while error amplification seemed to benefit more skilled subjects. Training with error amplification, however, limited transfer of learning. Random disturbing forces benefited learning and promoted transfer in all subjects, probably because it increased attention. These results suggest that learning a locomotor task can be optimized when errors are randomly evoked or amplified based on subjects' initial skill level.

  14. Optimization of CMOS image sensor utilizing variable temporal multisampling partial transfer technique to achieve full-frame high dynamic range with superior low light and stop motion capability

    Science.gov (United States)

    Kabir, Salman; Smith, Craig; Armstrong, Frank; Barnard, Gerrit; Schneider, Alex; Guidash, Michael; Vogelsang, Thomas; Endsley, Jay

    2018-03-01

    Differential binary pixel technology is a threshold-based timing, readout, and image reconstruction method that utilizes the subframe partial charge transfer technique in a standard four-transistor (4T) pixel CMOS image sensor to achieve a high dynamic range video with stop motion. This technology improves low light signal-to-noise ratio (SNR) by up to 21 dB. The method is verified in silicon using a Taiwan Semiconductor Manufacturing Company's 65 nm 1.1 μm pixel technology 1 megapixel test chip array and is compared with a traditional 4 × oversampling technique using full charge transfer to show low light SNR superiority of the presented technology.

  15. Locomotor problems among rural elderly population in a District of Aligarh, North India.

    Science.gov (United States)

    Maroof, Mohd; Ahmad, Anees; Khalique, Najam; Ansari, M Athar

    2017-01-01

    Locomotor functions decline with the age along with other physiological changes. This results in deterioration of the quality of life with decreased social and economic role in the society, as well as increased dependency, for the health care and other basic services. The demographic transition resulting in increased proportion of elderly may pose a burden to the health system. To find the prevalence of locomotor problems among the elderly population, and related sociodemographic factors. The study was a community-based cross-sectional study done at field practice area of Rural Health Training Centre, JN Medical College, AMU, Aligarh, Uttar Pradesh, India. A sample of 225 was drawn from 1018 elderly population aged 60 years and above using systematic random sampling with probability proportionate to size. Sociodemographic characteristics were obtained using pretested and predesigned questionnaire. Locomotor problems were assessed using the criteria used by National Sample Survey Organization. Data were analyzed using SPSS version 20. Chi-square test was used to test relationship of locomotor problems with sociodemographic factors. P locomotor problems among the elderly population was 25.8%. Locomotor problems were significantly associated with age, gender, and working status whereas no significant association with literacy status and marital status was observed. The study concluded that approximately one-fourth of the elderly population suffered from locomotor problems. The sociodemographic factors related to locomotor problems needs to be addressed properly to help them lead an independent and economically productive life.

  16. Locomotor recovery after spinal cord contusion injury in rats is improved by spontaneous exercise

    NARCIS (Netherlands)

    Gispen, W.H.; Meeteren, N.L. van; Eggers, L.; Lankhorst, A.J.; Hamers, F.P.

    2003-01-01

    We have recently shown that enriched environment (EE) housing significantly enhances locomotor recovery following spinal cord contusion injury (SCI) in rats. As the type and intensity of locomotor training with EE housing are rather poorly characterized, we decided to compare the effectiveness of EE

  17. Locomotor Tests Predict Community Mobility in Children and Youth with Cerebral Palsy

    Science.gov (United States)

    Ferland, Chantale; Moffet, Helene; Maltais, Desiree

    2012-01-01

    Ambulatory children and youth with cerebral palsy have limitations in locomotor capacities and in community mobility. The ability of three locomotor tests to predict community mobility in this population (N = 49, 27 boys, 6-16 years old) was examined. The tests were a level ground walking test, the 6-min-Walk-Test (6MWT), and two tests of advanced…

  18. Density functional theory study of the structural, electronic, lattice dynamical, and thermodynamic properties of Li4SiO4 and its capability for CO2 capture

    Energy Technology Data Exchange (ETDEWEB)

    Duan, Yuhua; Parlinski, K.

    2011-01-01

    The structural, electronic, lattice dynamical, optical, thermodynamic, and CO{sub 2} capture properties of monoclinic and triclinic phases of Li{sub 4}SiO{sub 4} are investigated by combining density functional theory with phonon lattice dynamics calculations. We found that these two phases have some similarities in their bulk and thermodynamic properties. The calculated bulk modulus and the cohesive energies of these two phases are close to each other. Although both of them are insulators, the monoclinic phase of Li{sub 4}SiO{sub 4} has a direct band gap of 5.24 eV while the triclinic Li{sub 4}SiO{sub 4} phase has an indirect band gap of 4.98 eV. In both phases of Li{sub 4}SiO{sub 4}, the s orbital of O mainly contributes to the lower-energy second valence band (VB{sub 2}) and the p orbitals contribute to the fist valence band (VB{sub 1}) and the conduction bands (CBs). The s orbital of Si mainly contributes to the lower portions of the VB1 and VB{sub 2}, and Si p orbitals mainly contribute to the higher portions of the VB{sub 1} and VB{sub 2}. The s and p orbitals of Li contribute to both VBs and to CBs, and Li p orbitals have a higher contribution than the Li s orbital. There is possibly a phonon soft mode existing in triclinic {gamma}-Li{sub 4}SiO{sub 4}; in the monoclinic Li{sub 4}SiO{sub 4}, there are three phonon soft modes, which correspond to the one type of Li disordered over a few sites. Their LO-TO splitting indicates that both phases of Li{sub 4}SiO{sub 4} are polar anisotropic materials. The calculated infrared absorption spectra for LO and TO modes are different for these two phases of Li{sub 4}SiO{sub 4}. The calculated relationships of the chemical potential versus temperature and CO{sub 2} pressure for reaction of Li{sub 4}SiO{sub 4} with CO{sub 2} shows that Li{sub 4}SiO{sub 4} could be a good candidate for a high-temperature CO{sub 2} sorbent while used for postcombustion capture technology.

  19. V3 spinal neurons establish a robust and balanced locomotor rhythm during walking.

    Science.gov (United States)

    Zhang, Ying; Narayan, Sujatha; Geiman, Eric; Lanuza, Guillermo M; Velasquez, Tomoko; Shanks, Bayle; Akay, Turgay; Dyck, Jason; Pearson, Keir; Gosgnach, Simon; Fan, Chen-Ming; Goulding, Martyn

    2008-10-09

    A robust and well-organized rhythm is a key feature of many neuronal networks, including those that regulate essential behaviors such as circadian rhythmogenesis, breathing, and locomotion. Here we show that excitatory V3-derived neurons are necessary for a robust and organized locomotor rhythm during walking. When V3-mediated neurotransmission is selectively blocked by the expression of the tetanus toxin light chain subunit (TeNT), the regularity and robustness of the locomotor rhythm is severely perturbed. A similar degeneration in the locomotor rhythm occurs when the excitability of V3-derived neurons is reduced acutely by ligand-induced activation of the allatostatin receptor. The V3-derived neurons additionally function to balance the locomotor output between both halves of the spinal cord, thereby ensuring a symmetrical pattern of locomotor activity during walking. We propose that the V3 neurons establish a regular and balanced motor rhythm by distributing excitatory drive between both halves of the spinal cord.

  20. Dynamics of Bloch oscillating transistor near bifurcation threshold and its applicability for common mode rejection capability of a differential pair BOT

    Science.gov (United States)

    Sarkar, Jayanta; Puska, Antti; Hassel, Juha; Hakonen, Pertti

    2014-03-01

    Bloch oscillating transistor (BOT) is mesoscopic current amplier based on a combination of a Josephson junction or a squid connected with a large resistor and a NIS junction. We have studied the dynamics of BOT near the bifurcation threshold. This is an important feature for an amplifier as this can be utilized to improve its performance characteristics. We have measured the I - V characteristics of the BOT with different base currents (IB) over a wide range of Josephson coupling energies (EJ) . The current gain (β) is found to be increasing with increasing IB and eventually diverging. We have found a record large β = 50 in our experiment. In order to determine the common mode rejection ratio (CMRR) of a differential pair BOT we have used two BOTs fabricated on the same chip. The common mode port is connected to the bases of the two BOTs and fed with varying voltages; simultaneously emitter currents of the two BOTs are recorded. In our experiment we found a 20dB of CMRR.

  1. Visual and kinesthetic locomotor imagery training integrated with auditory step rhythm for walking performance of patients with chronic stroke.

    Science.gov (United States)

    Kim, Jin-Seop; Oh, Duck-Won; Kim, Suhn-Yeop; Choi, Jong-Duk

    2011-02-01

    To compare the effect of visual and kinesthetic locomotor imagery training on walking performance and to determine the clinical feasibility of incorporating auditory step rhythm into the training. Randomized crossover trial. Laboratory of a Department of Physical Therapy. Fifteen subjects with post-stroke hemiparesis. Four locomotor imagery trainings on walking performance: visual locomotor imagery training, kinesthetic locomotor imagery training, visual locomotor imagery training with auditory step rhythm and kinesthetic locomotor imagery training with auditory step rhythm. The timed up-and-go test and electromyographic and kinematic analyses of the affected lower limb during one gait cycle. After the interventions, significant differences were found in the timed up-and-go test results between the visual locomotor imagery training (25.69 ± 16.16 to 23.97 ± 14.30) and the kinesthetic locomotor imagery training with auditory step rhythm (22.68 ± 12.35 to 15.77 ± 8.58) (P kinesthetic locomotor imagery training exhibited significantly increased activation in a greater number of muscles and increased angular displacement of the knee and ankle joints compared with the visual locomotor imagery training, and these effects were more prominent when auditory step rhythm was integrated into each form of locomotor imagery training. The activation of the hamstring during the swing phase and the gastrocnemius during the stance phase, as well as kinematic data of the knee joint, were significantly different for posttest values between the visual locomotor imagery training and the kinesthetic locomotor imagery training with auditory step rhythm (P kinesthetic locomotor imagery training than in the visual locomotor imagery training. The auditory step rhythm together with the locomotor imagery training produces a greater positive effect in improving the walking performance of patients with post-stroke hemiparesis.

  2. Effects of simultaneous exposure to stress and nicotine on nicotine-induced locomotor activation in adolescent and adult rats

    Energy Technology Data Exchange (ETDEWEB)

    Zago, A. [Laboratório de Farmacologia, Faculdade de Ciências Farmacêuticas, Universidade Estadual Paulista, Araraquara, SP (Brazil); Leão, R.M.; Carneiro-de-Oliveira, P.E. [Laboratório de Farmacologia, Faculdade de Ciências Farmacêuticas, Universidade Estadual Paulista, Araraquara, SP (Brazil); Programa Interinstitucional de Pós-Graduação em Ciências Fisiológicas, Universidade Federal de São Carlos/Universidade Estadual de São Paulo, Araraquara, SP (Brazil); Marin, M.T.; Cruz, F.C. [Laboratório de Farmacologia, Faculdade de Ciências Farmacêuticas, Universidade Estadual Paulista, Araraquara, SP (Brazil); Planeta, C.S. [Laboratório de Farmacologia, Faculdade de Ciências Farmacêuticas, Universidade Estadual Paulista, Araraquara, SP (Brazil); Programa Interinstitucional de Pós-Graduação em Ciências Fisiológicas, Universidade Federal de São Carlos/Universidade Estadual de São Paulo, Araraquara, SP (Brazil)

    2011-11-18

    Preclinical studies have shown that repeated stress experiences can result in an increase in the locomotor response to the subsequent administration of drugs of abuse, a phenomenon that has been termed behavioral cross-sensitization. Behavioral sensitization reflects neuroadaptive processes associated with drug addiction and drug-induced psychosis. Although crosssensitization between stress- and drug-induced locomotor activity has been clearly demonstrated in adult rats, few studies have evaluated this phenomenon in adolescent rats. In the present study, we determined if the simultaneous exposure to stress and nicotine was capable of inducing behavioral sensitization to nicotine in adolescent and adult rats. To this end, adolescent (postnatal day (P) 28-37) and adult (P60-67) rats received nicotine (0.4 mg/kg, sc) or saline (0.9% NaCl, sc) and were immediately subjected to restraint stress for 2 h once a day for 7 days. The control group for stress was undisturbed following nicotine or saline injections. Three days after the last exposure to stress and nicotine, rats were challenged with a single dose of nicotine (0.4 mg/kg, sc) or saline and nicotine-induced locomotion was then recorded for 30 min. In adolescent rats, nicotine caused behavioral sensitization only in animals that were simultaneously exposed to stress, while in adult rats nicotine promoted sensitization independently of stress exposure. These findings demonstrate that adolescent rats are more vulnerable to the effects of stress on behavioral sensitization to nicotine than adult rats.

  3. Effects of simultaneous exposure to stress and nicotine on nicotine-induced locomotor activation in adolescent and adult rats

    International Nuclear Information System (INIS)

    Zago, A.; Leão, R.M.; Carneiro-de-Oliveira, P.E.; Marin, M.T.; Cruz, F.C.; Planeta, C.S.

    2011-01-01

    Preclinical studies have shown that repeated stress experiences can result in an increase in the locomotor response to the subsequent administration of drugs of abuse, a phenomenon that has been termed behavioral cross-sensitization. Behavioral sensitization reflects neuroadaptive processes associated with drug addiction and drug-induced psychosis. Although crosssensitization between stress- and drug-induced locomotor activity has been clearly demonstrated in adult rats, few studies have evaluated this phenomenon in adolescent rats. In the present study, we determined if the simultaneous exposure to stress and nicotine was capable of inducing behavioral sensitization to nicotine in adolescent and adult rats. To this end, adolescent (postnatal day (P) 28-37) and adult (P60-67) rats received nicotine (0.4 mg/kg, sc) or saline (0.9% NaCl, sc) and were immediately subjected to restraint stress for 2 h once a day for 7 days. The control group for stress was undisturbed following nicotine or saline injections. Three days after the last exposure to stress and nicotine, rats were challenged with a single dose of nicotine (0.4 mg/kg, sc) or saline and nicotine-induced locomotion was then recorded for 30 min. In adolescent rats, nicotine caused behavioral sensitization only in animals that were simultaneously exposed to stress, while in adult rats nicotine promoted sensitization independently of stress exposure. These findings demonstrate that adolescent rats are more vulnerable to the effects of stress on behavioral sensitization to nicotine than adult rats

  4. Adaptation of a ladder beam walking task to assess locomotor recovery in mice following spinal cord injury

    Science.gov (United States)

    Cummings, Brian J.; Engesser-Cesar, Christie; Anderson, Aileen J.

    2007-01-01

    Locomotor impairments after spinal cord injury (SCI) are often assessed using open-field rating scales. These tasks have the advantage of spanning the range from complete paralysis to normal walking; however, they lack sensitivity at specific levels of recovery. Additionally, most supplemental assessments were developed in rats, not mice. For example, the horizontal ladder beam has been used to measure recovery in the rat after SCI. This parametric task results in a videotaped archival record of the event, is easily administered, and is unambiguously scored. Although a ladder beam apparatus for mice is available, its use in the assessment of recovery in SCI mice is rare, possibly because normative data for uninjured mice and the type of step misplacements injured mice exhibit is lacking. We report the development of a modified ladder beam instrument and scoring system to measure hindlimb recovery in vertebral T9 contusion spinal cord injured mice. The mouse ladder beam allows for the use of standard parametric statistical tests to assess locomotor recovery. Ladder beam performance is consistent across four strains of mice, there are no sex differences, and inter-rater reliability between observers is high. The ladder beam score is proportional to injury severity and can be used to easily separate mice capable of weight-supported stance up to mice with consistent forelimb to hindlimb coordination. Critically, horizontal ladder beam testing discriminates between mice that score identically in terms of stepping frequency in open-field testing. PMID:17197044

  5. Adaptation of a ladder beam walking task to assess locomotor recovery in mice following spinal cord injury.

    Science.gov (United States)

    Cummings, Brian J; Engesser-Cesar, Christie; Cadena, Gilbert; Anderson, Aileen J

    2007-02-27

    Locomotor impairments after spinal cord injury (SCI) are often assessed using open-field rating scales. These tasks have the advantage of spanning the range from complete paralysis to normal walking; however, they lack sensitivity at specific levels of recovery. Additionally, most supplemental assessments were developed in rats, not mice. For example, the horizontal ladder beam has been used to measure recovery in the rat after SCI. This parametric task results in a videotaped archival record of the event, is easily administered, and is unambiguously scored. Although a ladder beam apparatus for mice is available, its use in the assessment of recovery in SCI mice is rare, possibly because normative data for uninjured mice and the type of step misplacements injured mice exhibit is lacking. We report the development of a modified ladder beam instrument and scoring system to measure hindlimb recovery in vertebral T9 contusion spinal cord injured mice. The mouse ladder beam allows for the use of standard parametric statistical tests to assess locomotor recovery. Ladder beam performance is consistent across four strains of mice, there are no sex differences, and inter-rater reliability between observers is high. The ladder beam score is proportional to injury severity and can be used to easily separate mice capable of weight-supported stance up to mice with consistent forelimb to hindlimb coordination. Critically, horizontal ladder beam testing discriminates between mice that score identically in terms of stepping frequency in open-field testing.

  6. Evolving Capabilities for Virtual Globes

    Science.gov (United States)

    Glennon, A.

    2006-12-01

    Though thin-client spatial visualization software like Google Earth and NASA World Wind enjoy widespread popularity, a common criticism is their general lack of analytical functionality. This concern, however, is rapidly being addressed; standard and advanced geographic information system (GIS) capabilities are being developed for virtual globes--though not centralized into a single implementation or software package. The innovation is mostly originating from the user community. Three such capabilities relevant to the earth science, education, and emergency management communities are modeling dynamic spatial phenomena, real-time data collection and visualization, and multi-input collaborative databases. Modeling dynamic spatial phenomena has been facilitated through joining virtual globe geometry definitions--like KML--to relational databases. Real-time data collection uses short scripts to transform user-contributed data into a format usable by virtual globe software. Similarly, collaborative data collection for virtual globes has become possible by dynamically referencing online, multi-person spreadsheets. Examples of these functions include mapping flows within a karst watershed, real-time disaster assessment and visualization, and a collaborative geyser eruption spatial decision support system. Virtual globe applications will continue to evolve further analytical capabilities, more temporal data handling, and from nano to intergalactic scales. This progression opens education and research avenues in all scientific disciplines.

  7. Physiological Costs of Repetitive Courtship Displays in Cockroaches Handicap Locomotor Performance

    Science.gov (United States)

    Mowles, Sophie L.; Jepson, Natalie M.

    2015-01-01

    Courtship displays are typically thought to have evolved via female choice, whereby females select mates based on the characteristics of a display that is expected to honestly reflect some aspect of the male’s quality. Honesty is typically enforced by mechanistic costs and constraints that limit the level at which a display can be performed. It is becoming increasingly apparent that these costs may be energetic costs involved in the production of dynamic, often repetitive displays. A female attending to such a display may thus be assessing the physical fitness of a male as an index of his quality. Such assessment would provide information on his current physical quality as well as his ability to carry out other demanding activities, qualities with which a choosy female should want to provision her offspring. In the current study we use courtship interactions in the Cuban burrowing cockroach, Byrsotria fumigata to directly test whether courtship is associated with a signaler’s performance capacity. Males that had produced courtship displays achieved significantly lower speeds and distances in locomotor trials than non-courting control males. We also found that females mated more readily with males that produced a more vigorous display. Thus, males of this species have developed a strategy where they produce a demanding courtship display, while females choose males based on their ability to produce this display. Courtship displays in many taxa often involve dynamic repetitive actions and as such, signals of stamina in courtship may be more widespread than previously thought. PMID:26606147

  8. Control of locomotor stability in stabilizing and destabilizing environments.

    Science.gov (United States)

    Wu, Mengnan/Mary; Brown, Geoffrey; Gordon, Keith E

    2017-06-01

    To develop effective interventions targeting locomotor stability, it is crucial to understand how people control and modify gait in response to changes in stabilization requirements. Our purpose was to examine how individuals with and without incomplete spinal cord injury (iSCI) control lateral stability in haptic walking environments that increase or decrease stabilization demands. We hypothesized that people would adapt to walking in a predictable, stabilizing viscous force field and unpredictable destabilizing force field by increasing and decreasing feedforward control of lateral stability, respectively. Adaptations in feedforward control were measured using after-effects when fields were removed. Both groups significantly (pfeedforward adaptions to increase control of lateral stability. In contrast, in the destabilizing field, non-impaired subjects increased movement variability (p0.05). When the destabilizing field was removed, increases in movement variability persisted (pfeedforward decreases in resistance to perturbations. Published by Elsevier B.V.

  9. A Multiposture Locomotor Training Device with Force-Field Control

    Directory of Open Access Journals (Sweden)

    Jianfeng Sui

    2014-11-01

    Full Text Available This paper introduces a multiposture locomotor training device (MPLTD with a closed-loop control scheme based on joint angle feedback, which is able to overcome various difficulties resulting from mechanical vibration and the weight of trainer to achieve higher accuracy trajectory. By introducing the force-field control scheme used in the closed-loop control, the device can obtain the active-constrained mode including the passive one. The MPLTD is mainly composed of three systems: posture adjusting and weight support system, lower limb exoskeleton system, and control system, of which the lower limb exoskeleton system mainly includes the indifferent equilibrium mechanism with two degrees of freedom (DOF and the driving torque is calculated by the Lagrangian function. In addition, a series of experiments, the weight support and the trajectory accuracy experiment, demonstrate a good performance of mechanical structure and the closed-loop control.

  10. Proprioceptive input resets central locomotor rhythm in the spinal cat

    DEFF Research Database (Denmark)

    Conway, B. A.; Hultborn, H.; Kiehn, O.

    1987-01-01

    The reflex regulation of stepping is an important factor in adapting the step cycle to changes in the environment. The present experiments have examined the influence of muscle proprioceptors on centrally generated rhythmic locomotor activity in decerebrate unanesthetized cats with a spinal...... fictive locomotion in a coordinated fashion. An extensor group I volley delivered during a flexor burst would abruptly terminate the flexor activity and initiate an extensor burst. The same stimulus given during an extensor burst prolonged the extensor activity while delaying the appearance...... afferents. Thus an increased load of limb extensors during the stance phase would enhance and prolong extensor activity while simultaneously delaying the transition to the swing phase of the step cycle....

  11. Immature spinal locomotor output in children with Cerebral Palsy

    Directory of Open Access Journals (Sweden)

    Germana Cappellini

    2016-10-01

    Full Text Available Detailed descriptions of gait impairments have been reported in cerebral palsy (CP, but it is still unclear how maturation of the spinal motoneuron output is affected. Spatiotemporal alpha-motoneuron activation during walking can be assessed by mapping the electromyographic activity profiles from several, simultaneously recorded muscles onto the anatomical rostrocaudal location of the motoneuron pools in the spinal cord, and by means of factor analysis of the muscle activity profiles. Here, we analysed gait kinematics and EMG activity of 11 pairs of bilateral muscles with lumbosacral innervation in 35 children with CP (19 diplegic, 16 hemiplegic, 2-12 years and 33 typically developing (TD children (1-12 years. TD children showed a progressive reduction of EMG burst durations and a gradual reorganization of the spatiotemporal motoneuron output with increasing age. By contrast, children with CP showed very limited age-related changes of EMG durations and motoneuron output, as well as of limb intersegmental coordination and foot trajectory control (on both sides for diplegic children and the affected side for hemiplegic children. Factorization of the EMG signals revealed a comparable structure of the motor output in children with CP and TD children, but significantly wider temporal activation patterns in children with CP, resembling the patterns of much younger TD infants. A similar picture emerged when considering the spatiotemporal maps of alpha-motoneuron activation. Overall, the results are consistent with the idea that early injuries to developing motor regions of the brain substantially affect the maturation of the spinal locomotor output and consequently the future locomotor behaviour.

  12. Locomotor sensory organization test: a novel paradigm for the assessment of sensory contributions in gait.

    Science.gov (United States)

    Chien, Jung Hung; Eikema, Diderik-Jan Anthony; Mukherjee, Mukul; Stergiou, Nicholas

    2014-12-01

    Feedback based balance control requires the integration of visual, proprioceptive and vestibular input to detect the body's movement within the environment. When the accuracy of sensory signals is compromised, the system reorganizes the relative contributions through a process of sensory recalibration, for upright postural stability to be maintained. Whereas this process has been studied extensively in standing using the Sensory Organization Test (SOT), less is known about these processes in more dynamic tasks such as locomotion. In the present study, ten healthy young adults performed the six conditions of the traditional SOT to quantify standing postural control when exposed to sensory conflict. The same subjects performed these six conditions using a novel experimental paradigm, the Locomotor SOT (LSOT), to study dynamic postural control during walking under similar types of sensory conflict. To quantify postural control during walking, the net Center of Pressure sway variability was used. This corresponds to the Performance Index of the center of pressure trajectory, which is used to quantify postural control during standing. Our results indicate that dynamic balance control during locomotion in healthy individuals is affected by the systematic manipulation of multisensory inputs. The sway variability patterns observed during locomotion reflect similar balance performance with standing posture, indicating that similar feedback processes may be involved. However, the contribution of visual input is significantly increased during locomotion, compared to standing in similar sensory conflict conditions. The increased visual gain in the LSOT conditions reflects the importance of visual input for the control of locomotion. Since balance perturbations tend to occur in dynamic tasks and in response to environmental constraints not present during the SOT, the LSOT may provide additional information for clinical evaluation on healthy and deficient sensory processing.

  13. Three-axis optical force plate for studies in small animal locomotor mechanics

    International Nuclear Information System (INIS)

    Hsieh, S. Tonia

    2006-01-01

    The use of force plates to measure whole-body locomotor mechanics is a well-established technique. However, commercially available force plates are not sensitive enough for use on small-bodied vertebrates or invertebrates. The standard design for single- and multiple-axis, high-sensitivity force plates built by individual research groups uses semiconductor foil strain gauges to measure deflections; yet foil strain gauges are highly temperature and position sensitive, resulting in a drifting base line and nonlinear responses. I present here a design for a three-axis optical force plate that was successfully calibrated to measure forces as small as 1.5 mN and is capable of determining the position of center of pressure with a mean error of 0.07 cm along the X axis and 0.13 cm along the Y axis. Using optical sensors instead of foil strain gauges to measure deflection, this force plate is not subject to temperature-related drift and is more robust against slight positioning inaccuracies. This force plate was used to measure forces produced by amphibious fishes weighing less than 2 g as they jumped off the force platform

  14. Building Service Provider Capabilities

    DEFF Research Database (Denmark)

    Brandl, Kristin; Jaura, Manya; Ørberg Jensen, Peter D.

    2015-01-01

    In this paper we study whether and how the interaction between clients and the service providers contributes to the development of capabilities in service provider firms. In situations where such a contribution occurs, we analyze how different types of activities in the production process...... process. We find that clients influence the development of human capital capabilities and management capabilities in reciprocally produced services. While in sequential produced services clients influence the development of organizational capital capabilities and management capital capabilities....... of the services, such as sequential or reciprocal task activities, influence the development of different types of capabilities. We study five cases of offshore-outsourced knowledge-intensive business services that are distinguished according to their reciprocal or sequential task activities in their production...

  15. Injections of the selective adenosine A2A antagonist MSX-3 into the nucleus accumbens core attenuate the locomotor suppression induced by haloperidol in rats.

    Science.gov (United States)

    Ishiwari, Keita; Madson, Lisa J; Farrar, Andrew M; Mingote, Susana M; Valenta, John P; DiGianvittorio, Michael D; Frank, Lauren E; Correa, Merce; Hockemeyer, Jörg; Müller, Christa; Salamone, John D

    2007-03-28

    There is considerable evidence of interactions between adenosine A2A receptors and dopamine D2 receptors in striatal areas, and antagonists of the A2A receptor have been shown to reverse the motor effects of DA antagonists in animal models. The D2 antagonist haloperidol produces parkinsonism in humans, and also induces motor effects in rats, such as suppression of locomotion. The present experiments were conducted to study the ability of the adenosine A2A antagonist MSX-3 to reverse the locomotor effects of acute or subchronic administration of haloperidol in rats. Systemic (i.p.) injections of MSX-3 (2.5-10.0 mg/kg) were capable of attenuating the suppression of locomotion induced by either acute or repeated (i.e., 14 day) administration of 0.5 mg/kg haloperidol. Bilateral infusions of MSX-3 directly into the nucleus accumbens core (2.5 microg or 5.0 microg in 0.5 microl per side) produced a dose-related increase in locomotor activity in rats treated with 0.5 mg/kg haloperidol either acutely or repeatedly. There were no overall significant effects of MSX-3 infused directly into the dorsomedial nucleus accumbens shell or the ventrolateral neostriatum. These results indicate that antagonism of adenosine A2A receptors can attenuate the locomotor suppression produced by DA antagonism, and that this effect may be at least partially mediated by A2A receptors in the nucleus accumbens core. These studies suggest that adenosine and dopamine systems interact to modulate the locomotor and behavioral activation functions of nucleus accumbens core.

  16. Developing the content of a locomotor disability scale for adults in Bangladesh: a qualitative study.

    Science.gov (United States)

    Mahmud, Ilias; Clarke, Lynda; Ploubidis, George B

    2017-01-01

    Bangladesh has an estimated 17 million adults with disabilities. A significant proportion of them are believed to have locomotor disabilities. There are over 300 non-governmental organizations providing different types of rehabilitation services to them. However, there is no locally developed and validated locomotor disability measurement scale in Bangladesh. The purpose of this study was to develop a locomotor disability scale with disability indicators suitable for adults in Bangladesh. Semi-structured interviews were conducted with 25 purposively selected adults with locomotor disabilities to generate scale items. At the second stage, cognitive interviews were conducted with 12 purposively selected adults with locomotor disabilities in order to refine the measurement questions and response categories. Data were analysed using the framework technique- identifying, abstracting, charting and matching themes across the interviews. For a locomotor disability scale, 70 activities (disability indicators) were identified: 37 mobility activities, 9 activities of daily living, 17 work/productivity activities and 7 leisure activities. Cognitive interviews revealed that when asking the respondents to rate their difficulty in performing the activities, instead of just mentioning the activity name, such as taking a bath or shower, a detailed description of the activity and response options were necessary to ensure consistent interpretation of the disability indicators and response options across all respondents. Identifying suitable disability indicators was the first step in developing a locomotor disability scale for adults in Bangladesh. Interviewing adults with locomotor disabilities in Bangladesh ensured that the locomotor disability scale is of relevance to them and consequently it has excellent content validity. Further research is needed to evaluate the psychometric properties of this scale.

  17. Capability Handbook- offline metrology

    DEFF Research Database (Denmark)

    Islam, Aminul; Marhöfer, David Maximilian; Tosello, Guido

    This offline metrological capability handbook has been made in relation to HiMicro Task 3.3. The purpose of this document is to assess the metrological capability of the HiMicro partners and to gather the information of all available metrological instruments in the one single document. It provides...

  18. Developing Alliance Capabilities

    DEFF Research Database (Denmark)

    Heimeriks, Koen H.; Duysters, Geert; Vanhaverbeke, Wim

    This paper assesses the differential performance effects of learning mechanisms on the development of alliance capabilities. Prior research has suggested that different capability levels could be identified in which specific intra-firm learning mechanisms are used to enhance a firm's alliance...

  19. Telematics Options and Capabilities

    Energy Technology Data Exchange (ETDEWEB)

    Hodge, Cabell [National Renewable Energy Laboratory (NREL), Golden, CO (United States)

    2017-09-05

    This presentation describes the data tracking and analytical capabilities of telematics devices. Federal fleet managers can use the systems to keep their drivers safe, maintain a fuel efficient fleet, ease their reporting burden, and save money. The presentation includes an example of how much these capabilities can save fleets.

  20. Organization, Evolution, Cognition and Dynamic Capabilities

    NARCIS (Netherlands)

    Nooteboom, B.

    2006-01-01

    Using insights from 'embodied cognition' and a resulting 'cognitive theory of the firm', I aim to contribute to the further development of evolutionary theory of organizations, in the specification of organizations as 'interactors' that carry organizational competencies as 'replicators', within

  1. Atlantic Test Range. Dynamic RCS Measurement Capability

    National Research Council Canada - National Science Library

    2000-01-01

    .... These systems include radars (fighter/attack, sea surveillance, and AEW), Navigation (IFF, GPS, and INS), communications (voice and data link), reconnaissance systems, antenna systems, forward looking infrared systems and ASW systems...

  2. Acquisition-based Dynamic Reconfiguration Capabilities

    NARCIS (Netherlands)

    Amiryany Araghy, N.; Huysman, M.H.; de Man, A.P.; Cloodt, M.; Demetriss, V.; Weber, Y.; Kaufmann, R.; Tarba, S.

    2009-01-01

    The success of knowledge acquisitions is dependent upon firm’s ability to integrate knowledge-based resources and thus share knowledge, in order to innovate. Regardless of the increasing number of knowledge acquisitions, however, an understanding of how successful firms direct their knowledge

  3. Locomotor Sensory Organization Test: How Sensory Conflict Affects the Temporal Structure of Sway Variability During Gait.

    Science.gov (United States)

    Chien, Jung Hung; Mukherjee, Mukul; Siu, Ka-Chun; Stergiou, Nicholas

    2016-05-01

    When maintaining postural stability temporally under increased sensory conflict, a more rigid response is used where the available degrees of freedom are essentially frozen. The current study investigated if such a strategy is also utilized during more dynamic situations of postural control as is the case with walking. This study attempted to answer this question by using the Locomotor Sensory Organization Test (LSOT). This apparatus incorporates SOT inspired perturbations of the visual and the somatosensory system. Ten healthy young adults performed the six conditions of the traditional SOT and the corresponding six conditions on the LSOT. The temporal structure of sway variability was evaluated from all conditions. The results showed that in the anterior posterior direction somatosensory input is crucial for postural control for both walking and standing; visual input also had an effect but was not as prominent as the somatosensory input. In the medial lateral direction and with respect to walking, visual input has a much larger effect than somatosensory input. This is possibly due to the added contributions by peripheral vision during walking; in standing such contributions may not be as significant for postural control. In sum, as sensory conflict increases more rigid and regular sway patterns are found during standing confirming the previous results presented in the literature, however the opposite was the case with walking where more exploratory and adaptive movement patterns are present.

  4. Dynamic contrast-enhanced perfusion area-detector CT assessed with various mathematical models: Its capability for therapeutic outcome prediction for non-small cell lung cancer patients with chemoradiotherapy as compared with that of FDG-PET/CT

    Energy Technology Data Exchange (ETDEWEB)

    Ohno, Yoshiharu, E-mail: yosirad@kobe-u.ac.jp [Division of Functional and Diagnostic Imaging Research, Department of Radiology, Kobe University Graduate School of Medicine, Kobe (Japan); Advanced Biomedical Imaging Research Center, Kobe University Graduate School of Medicine, Kobe (Japan); Fujisawa, Yasuko [Toshiba Medical Systems Corporation, Otawara (Japan); Koyama, Hisanobu; Kishida, Yuji; Seki, Shinichiro [Division of Radiology, Department of Radiology, Kobe University Graduate School of Medicine, Kobe (Japan); Sugihara, Naoki [Toshiba Medical Systems Corporation, Otawara (Japan); Yoshikawa, Takeshi [Division of Functional and Diagnostic Imaging Research, Department of Radiology, Kobe University Graduate School of Medicine, Kobe (Japan); Advanced Biomedical Imaging Research Center, Kobe University Graduate School of Medicine, Kobe (Japan)

    2017-01-15

    Purpose: To directly compare the capability of dynamic first-pass contrast-enhanced (CE-) perfusion area-detector CT (ADCT) and PET/CT for early prediction of treatment response, disease progression and overall survival of non-small cell carcinoma (NSCLC) patients treated with chemoradiotherapy. Materials and methods: Fifty-three consecutive Stage IIIB NSCLC patients who had undergone PET/CT, dynamic first-pass CE-perfusion ADCT, chemoradiotherapy, and follow-up examination were enrolled in this study. They were divided into two groups: 1) complete or partial response (CR + PR) and 2) stable or progressive disease (SD + PD). Pulmonary arterial and systemic arterial perfusions and total perfusion were assessed at targeted lesions with the dual-input maximum slope method, permeability surface and distribution volume with the Patlak plot method, tumor perfusion with the single-input maximum slope method, and SUV{sub max}, and results were averaged to determine final values for each patient. Next, step-wise regression analysis was used to determine which indices were the most useful for predicting therapeutic effect. Finally, overall survival of responders and non-responders assessed by using the indices that had a significant effect on prediction of therapeutic outcome was statistically compared. Results: The step-wise regression test showed that therapeutic effect (r{sup 2} = 0.63, p = 0.01) was significantly affected by the following three factors in order of magnitude of impact: systemic arterial perfusion, total perfusion, and SUV{sub max}. Mean overall survival showed a significant difference for total perfusion (p = 0.003) and systemic arterial perfusion (p = 0.04). Conclusion: Dynamic first-pass CE-perfusion ADCT as well as PET/CT are useful for treatment response prediction in NSCLC patients treated with chemoradiotherapy.

  5. Dynamic contrast-enhanced perfusion area-detector CT assessed with various mathematical models: Its capability for therapeutic outcome prediction for non-small cell lung cancer patients with chemoradiotherapy as compared with that of FDG-PET/CT

    International Nuclear Information System (INIS)

    Ohno, Yoshiharu; Fujisawa, Yasuko; Koyama, Hisanobu; Kishida, Yuji; Seki, Shinichiro; Sugihara, Naoki; Yoshikawa, Takeshi

    2017-01-01

    Purpose: To directly compare the capability of dynamic first-pass contrast-enhanced (CE-) perfusion area-detector CT (ADCT) and PET/CT for early prediction of treatment response, disease progression and overall survival of non-small cell carcinoma (NSCLC) patients treated with chemoradiotherapy. Materials and methods: Fifty-three consecutive Stage IIIB NSCLC patients who had undergone PET/CT, dynamic first-pass CE-perfusion ADCT, chemoradiotherapy, and follow-up examination were enrolled in this study. They were divided into two groups: 1) complete or partial response (CR + PR) and 2) stable or progressive disease (SD + PD). Pulmonary arterial and systemic arterial perfusions and total perfusion were assessed at targeted lesions with the dual-input maximum slope method, permeability surface and distribution volume with the Patlak plot method, tumor perfusion with the single-input maximum slope method, and SUV max , and results were averaged to determine final values for each patient. Next, step-wise regression analysis was used to determine which indices were the most useful for predicting therapeutic effect. Finally, overall survival of responders and non-responders assessed by using the indices that had a significant effect on prediction of therapeutic outcome was statistically compared. Results: The step-wise regression test showed that therapeutic effect (r 2 = 0.63, p = 0.01) was significantly affected by the following three factors in order of magnitude of impact: systemic arterial perfusion, total perfusion, and SUV max . Mean overall survival showed a significant difference for total perfusion (p = 0.003) and systemic arterial perfusion (p = 0.04). Conclusion: Dynamic first-pass CE-perfusion ADCT as well as PET/CT are useful for treatment response prediction in NSCLC patients treated with chemoradiotherapy.

  6. Dynamic contrast-enhanced perfusion area-detector CT assessed with various mathematical models: Its capability for therapeutic outcome prediction for non-small cell lung cancer patients with chemoradiotherapy as compared with that of FDG-PET/CT.

    Science.gov (United States)

    Ohno, Yoshiharu; Fujisawa, Yasuko; Koyama, Hisanobu; Kishida, Yuji; Seki, Shinichiro; Sugihara, Naoki; Yoshikawa, Takeshi

    2017-01-01

    To directly compare the capability of dynamic first-pass contrast-enhanced (CE-) perfusion area-detector CT (ADCT) and PET/CT for early prediction of treatment response, disease progression and overall survival of non-small cell carcinoma (NSCLC) patients treated with chemoradiotherapy. Fifty-three consecutive Stage IIIB NSCLC patients who had undergone PET/CT, dynamic first-pass CE-perfusion ADCT, chemoradiotherapy, and follow-up examination were enrolled in this study. They were divided into two groups: 1) complete or partial response (CR+PR) and 2) stable or progressive disease (SD+PD). Pulmonary arterial and systemic arterial perfusions and total perfusion were assessed at targeted lesions with the dual-input maximum slope method, permeability surface and distribution volume with the Patlak plot method, tumor perfusion with the single-input maximum slope method, and SUV max , and results were averaged to determine final values for each patient. Next, step-wise regression analysis was used to determine which indices were the most useful for predicting therapeutic effect. Finally, overall survival of responders and non-responders assessed by using the indices that had a significant effect on prediction of therapeutic outcome was statistically compared. The step-wise regression test showed that therapeutic effect (r 2 =0.63, p=0.01) was significantly affected by the following three factors in order of magnitude of impact: systemic arterial perfusion, total perfusion, and SUV max . Mean overall survival showed a significant difference for total perfusion (p=0.003) and systemic arterial perfusion (p=0.04). Dynamic first-pass CE-perfusion ADCT as well as PET/CT are useful for treatment response prediction in NSCLC patients treated with chemoradiotherapy. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  7. Kokkos' Task DAG Capabilities.

    Energy Technology Data Exchange (ETDEWEB)

    Edwards, Harold C. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Ibanez, Daniel Alejandro [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2017-09-01

    This report documents the ASC/ATDM Kokkos deliverable "Production Portable Dy- namic Task DAG Capability." This capability enables applications to create and execute a dynamic task DAG ; a collection of heterogeneous computational tasks with a directed acyclic graph (DAG) of "execute after" dependencies where tasks and their dependencies are dynamically created and destroyed as tasks execute. The Kokkos task scheduler executes the dynamic task DAG on the target execution resource; e.g. a multicore CPU, a manycore CPU such as Intel's Knights Landing (KNL), or an NVIDIA GPU. Several major technical challenges had to be addressed during development of Kokkos' Task DAG capability: (1) portability to a GPU with it's simplified hardware and micro- runtime, (2) thread-scalable memory allocation and deallocation from a bounded pool of memory, (3) thread-scalable scheduler for dynamic task DAG, (4) usability by applications.

  8. Cell phone-generated radio frequency electromagnetic field effects on the locomotor behaviors of the fishes Poecilia reticulata and Danio rerio.

    Science.gov (United States)

    Lee, David; Lee, Joshua; Lee, Imshik

    2015-01-01

    The locomotor behavior of small fish was characterized under a cell phone-generated radio frequency electromagnetic field (RF EMF). The trajectory of movement of 10 pairs of guppy (Poecilia reticulate) and 15 pairs of Zebrafish (Danio rerio) in a fish tank was recorded and tracked under the presence of a cell phone-generated RF EMF. The measures were based on spatial and temporal distributions. A time-series trajectory was utilized to emphasize the dynamic nature of locomotor behavior. Fish movement was recorded in real-time. Their spatial, velocity, turning angle and sinuosity distribution were analyzed in terms of F(v,x), P[n(x,t)], P(v), F (θ) and F(s), respectively. In addition, potential temperature elevation caused by a cellular phone was also examined. We demonstrated that a cellular phone-induced temperature elevation was not relevant, and that our measurements reflected RF EMF-induced effects on the locomotor behavior of Poecilia reticulata and Danio rerio. Fish locomotion was observed under normal conditions, in the visual presence of a cell phone, after feeding, and under starvation. Fish locomotor behavior was random both in normal conditions and in the presence of an off-signaled cell phone. However, there were significant changes in the locomotion of the fish after feeding under the RF EMF. The locomotion of the fed fish was affected in terms of changes in population and velocity distributions under the presence of the RF EMF emitted by the cell phone. There was, however, no significant difference in angular distribution.

  9. Acetylcholinesterase inhibition and altered locomotor behavior in the carabid beetle pterostichus

    DEFF Research Database (Denmark)

    Jensen, Charlotte S.; Krause-Jensen, Lone; Baatrup, Erik

    1997-01-01

    -aided video tracking, whereupon the whole body AChE activity was measured in the individual beetle. AChE inhibition was strongly correlated with dimethoate dose in both sexes. Alterations in the locomotor behavior were directly correlated with AChE inhibition in male beetles, which responded by reducing...... to locomotor behavior, representing a general effect biomarker at the organismal level. Both sexes of the carabid beetle Pterostichus cupreus were intoxicated with three doses of the organophosphorous insecticide dimethoate. Five elements of their locomotor behavior were measured for 4 h employing computer...... the time in locomotion, average velocity, and path length and by increasing the turning rate and frequency of stops. Females responded similarly at the two highest doses, whereas their locomotor behavior was not significantly different from the control group at the lowest dimethoate dose, suggesting a sex...

  10. Effects of cholestasis on learning and locomotor activity in bile duct ligated rats.

    Science.gov (United States)

    Hosseini, Nasrin; Alaei, Hojjatallah; Nasehi, Mohammad; Radahmadi, Maryam; Mohammad Reza, Zarrindast

    2014-01-01

    Cognitive functions are impaired in patients with liver disease. Bile duct ligation causes cholestasis that impairs liver function. This study investigated the impact of cholestasis progression on the acquisition and retention times in the passive avoidance test and on the locomotor activity of rats. Cholestasis was induced in male Wistar rats by ligating the main bile duct. Locomotor activity, learning and memory were assessed by the passive avoidance learning test at day 7, day 14, and day 21 post-bile duct ligation. The serum levels of bilirubin, alanine aminotransferase, and alkaline phosphatase were measured. The results showed that acquisition time and locomotor activity were not affected at day 7 and day 14, but they were significantly (P locomotor activity were impaired at 21 days after bile duct ligation following the progression of cholestasis.

  11. Comparative limb proportions reveal differential locomotor morphofunctions of alligatoroids and crocodyloids

    Science.gov (United States)

    Iijima, Masaya; Kubo, Tai; Kobayashi, Yoshitsugu

    2018-03-01

    Although two major clades of crocodylians (Alligatoroidea and Crocodyloidea) were split during the Cretaceous period, relatively few morphological and functional differences between them have been known. In addition, interaction of multiple morphofunctional systems that differentiated their ecology has barely been assessed. In this study, we examined the limb proportions of crocodylians to infer the differences of locomotor functions between alligatoroids and crocodyloids, and tested the correlation of locomotor and feeding morphofunctions. Our analyses revealed crocodyloids including Gavialis have longer stylopodia (humerus and femur) than alligatoroids, indicating that two groups may differ in locomotor functions. Fossil evidence suggested that alligatoroids have retained short stylopodia since the early stage of their evolution. Furthermore, rostral shape, an indicator of trophic function, is correlated with limb proportions, where slender-snouted piscivorous taxa have relatively long stylopodia and short overall limbs. In combination, trophic and locomotor functions might differently delimit the ecological opportunity of alligatoroids and crocodyloids in the evolution of crocodylians.

  12. Woodlouse locomotor behavior in the assessment of clean and contaminated field sites

    Energy Technology Data Exchange (ETDEWEB)

    Bayley, M.; Baatrup, E. [Aarhus Univ. (Denmark). Inst. of Biological Sciences; Bjerregaard, P. [Odense Univ. (Denmark). Inst. of Biology

    1997-11-01

    Specimens of the woodlouse Oniscus asellus were collected at four clean field sites and from a recently closed iron foundry heavily contaminated with zinc, lead, chromium, and nickel. Each of the 30 woodlice per group was housed individually and acclimatized to laboratory conditions for 2 d on a humid plaster of paris substrate. Thereafter, the locomotor behavior of each animal was measured for 4 h employing automated computer-aided video tracking. Linear discriminant analysis of five locomotor parameters revealed average velocity and path length as the principle components separating the polluted site and control animals. Post hoc analysis of the discriminant variable for animals from all five sites showed that the animals from the polluted site where significantly hyperactive when compared to all controls. Further, control animals collected from sites separated by several hundred kilometers were remarkably similar in their locomotor behavior. This preliminary study highlights the potential utility of quantitative analysis of animal locomotor behavior in environmental monitoring.

  13. Locomotor activity and tissue levels following acute administration of lambda- and gamma-cyhalothrin in rats

    Science.gov (United States)

    Pyrethroids produce neurotoxicity that depends, in part, on the chemical structure. Common behavioral effects include locomotor activity changes and specific toxic syndromes (types I and II). In general these neurobehavioral effects correlate well with peak internal dose metric...

  14. FMEF/experimental capabilities

    International Nuclear Information System (INIS)

    Burgess, C.A.; Dronen, V.R.

    1981-01-01

    The Fuels and Materials Examination Facility (FMEF), under construction at the Hanford site north of Richland, Washington, will be one of the most modern facilities offering irradiated fuels and materials examination capabilities and fuel fabrication development technologies. Scheduled for completion in 1984, the FMEF will provide examination capability for fuel assemblies, fuel pins and test pins irradiated in the FFTF. Various functions of the FMEF are described, with emphasis on experimental data-gathering capabilities in the facility's Nondestructive and Destructive examination cell complex

  15. KSC Technical Capabilities Website

    Science.gov (United States)

    Nufer, Brian; Bursian, Henry; Brown, Laurette L.

    2010-01-01

    This document is the website pages that review the technical capabilities that the Kennedy Space Center (KSC) has for partnership opportunities. The purpose of this information is to make prospective customers aware of the capabilities and provide an opportunity to form relationships with the experts at KSC. The technical capabilities fall into these areas: (1) Ground Operations and Processing Services, (2) Design and Analysis Solutions, (3) Command and Control Systems / Services, (4) Materials and Processes, (5) Research and Technology Development and (6) Laboratories, Shops and Test Facilities.

  16. Locomotor activity: A distinctive index in morphine self-administration in rats

    OpenAIRE

    Zhang, Jian-Jun; Kong, Qingyao

    2017-01-01

    Self-administration of addictive drugs is a widely used tool for studying behavioral, neurobiological, and genetic factors in addiction. However, how locomotor activity is affected during self-administration of addictive drugs has not been extensively studied. In our present study, we tested the locomotor activity levels during acquisition, extinction and reinstatement of morphine self-administration in rats. We found that compared with saline self-administration (SA), rats that trained with ...

  17. V1 spinal neurons regulate the speed of vertebrate locomotor outputs

    DEFF Research Database (Denmark)

    Gosgnach, Simon; Lanuza, Guillermo M.; Butt, Simon J B

    2006-01-01

    The neuronal networks that generate vertebrate movements such as walking and swimming are embedded in the spinal cord1-3. These networks, which are referred to as central pattern generators (CPGs), are ideal systems for determining how ensembles of neurons generate simple behavioural outputs...... for inhibition in regulating the frequency of the locomotor CPG rhythm, and also suggest that V1 neurons may have an evolutionarily conserved role in controlling the speed of vertebrate locomotor movements....

  18. Ankle voluntary movement enhancement following robotic-assisted locomotor training in spinal cord injury

    OpenAIRE

    Varoqui, Deborah; Niu, Xun; Mirbagheri, Mehdi M

    2014-01-01

    Background In incomplete spinal cord injury (iSCI), sensorimotor impairments result in severe limitations to ambulation. To improve walking capacity, physical therapies using robotic-assisted locomotor devices, such as the Lokomat, have been developed. Following locomotor training, an improvement in gait capabilities—characterized by increases in the over-ground walking speed and endurance—is generally observed in patients. To better understand the mechanisms underlying these improvements, we...

  19. Engagement of the Rat Hindlimb Motor Cortex across Natural Locomotor Behaviors

    OpenAIRE

    DiGiovanna, J.; Dominici, N.; Friedli, L.; Rigosa, J.; Duis, S.; Kreider, J.; Beauparlant, J.; van den Brand, R.; Schieppati, M.; Micera, S.; Courtine, G.

    2016-01-01

    Contrary to cats and primates, cortical contribution to hindlimb locomotor movements is not critical in rats. However, the importance of the motor cortex to regain locomotion after neurological disorders in rats suggests that cortical engagement in hindlimb motor control may depend on the behavioral context. To investigate this possibility, we recorded whole-body kinematics, muscle synergies, and hindlimb motor cortex modulation in freely moving rats performing a range of natural locomotor pr...

  20. Characterization of the Dynamics of Climate Systems and Identification of Missing Mechanisms Impacting the Long Term Predictive Capabilities of Global Climate Models Utilizing Dynamical Systems Approaches to the Analysis of Observed and Modeled Climate

    Energy Technology Data Exchange (ETDEWEB)

    Bhatt, Uma S. [Univ. of Alaska, Fairbanks, AK (United States). Dept. of Atmospheric Sciences; Wackerbauer, Renate [Univ. of Alaska, Fairbanks, AK (United States). Dept. of Physics; Polyakov, Igor V. [Univ. of Alaska, Fairbanks, AK (United States). Dept. of Atmospheric Sciences; Newman, David E. [Univ. of Alaska, Fairbanks, AK (United States). Dept. of Physics; Sanchez, Raul E. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). Fusion Energy Division; Univ. Carlos III de Madrid (Spain)

    2015-11-13

    The goal of this research was to apply fractional and non-linear analysis techniques in order to develop a more complete characterization of climate change and variability for the oceanic, sea ice and atmospheric components of the Earth System. This research applied two measures of dynamical characteristics of time series, the R/S method of calculating the Hurst exponent and Renyi entropy, to observational and modeled climate data in order to evaluate how well climate models capture the long-term dynamics evident in observations. Fractional diffusion analysis was applied to ARGO ocean buoy data to quantify ocean transport. Self organized maps were applied to North Pacific sea level pressure and analyzed in ways to improve seasonal predictability for Alaska fire weather. This body of research shows that these methods can be used to evaluate climate models and shed light on climate mechanisms (i.e., understanding why something happens). With further research, these methods show promise for improving seasonal to longer time scale forecasts of climate.

  1. Resources, constraints and capabilities

    NARCIS (Netherlands)

    Dhondt, S.; Oeij, P.R.A.; Schröder, A.

    2018-01-01

    Human and financial resources as well as organisational capabilities are needed to overcome the manifold constraints social innovators are facing. To unlock the potential of social innovation for the whole society new (social) innovation friendly environments and new governance structures

  2. a Capability approach

    African Journals Online (AJOL)

    efforts towards gender equality in education as a means of achieving social justice. ... should mean that a lot of capability approach-oriented commentators are ... processes, their forms of exercising power, and their rules, unwritten cultures, ...

  3. Engineering Capabilities and Partnerships

    Science.gov (United States)

    Poulos, Steve

    2010-01-01

    This slide presentation reviews the engineering capabilities at Johnson Space Center, The presentation also reviews the partnerships that have resulted in successfully designed and developed projects that involved commercial and educational institutions.

  4. Sex differences in the acute locomotor response to methamphetamine in BALB/c mice.

    Science.gov (United States)

    Ohia-Nwoko, Odochi; Haile, Colin N; Kosten, Therese A

    2017-06-01

    Women use methamphetamine more frequently than men and are more vulnerable to its negative psychological effects. Rodent models have been an essential tool for evaluating the sex-dependent effects of psychostimulants; however, evidence of sex differences in the behavioral responses to methamphetamine in mice is lacking. In the present study, we investigated acute methamphetamine-induced (1mg/kg and 4mg/kg) locomotor activation in female and male BALB/c mice. We also evaluated whether basal locomotor activity was associated with the methamphetamine-induced locomotor response. The results indicated that female BALB/c mice displayed enhanced methamphetamine-induced locomotor activity compared to males, while basal locomotor activity was positively correlated with methamphetamine-induced activity in males, but not females. This study is the first to show sex-dependent locomotor effects of methamphetamine in BALB/c mice. Our observations emphasize the importance of considering sex when assessing behavioral responses to methamphetamine. Copyright © 2017 Elsevier B.V. All rights reserved.

  5. Cocaine locomotor activation, sensitization and place preference in six inbred strains of mice

    Science.gov (United States)

    2011-01-01

    Background The expanding set of genomics tools available for inbred mouse strains has renewed interest in phenotyping larger sets of strains. The present study aims to explore phenotypic variability among six commonly-used inbred mouse strains to both the rewarding and locomotor stimulating effects of cocaine in a place conditioning task, including several strains or substrains that have not yet been characterized for some or all of these behaviors. Methods C57BL/6J (B6), BALB/cJ (BALB), C3H/HeJ (C3H), DBA/2J (D2), FVB/NJ (FVB) and 129S1/SvImJ (129) mice were tested for conditioned place preference to 20 mg/kg cocaine. Results Place preference was observed in most strains with the exception of D2 and 129. All strains showed a marked increase in locomotor activity in response to cocaine. In BALB mice, however, locomotor activation was context-dependent. Locomotor sensitization to repeated exposure to cocaine was most significant in 129 and D2 mice but was absent in FVB mice. Conclusions Genetic correlations suggest that no significant correlation between conditioned place preference, acute locomotor activation, and locomotor sensitization exists among these strains indicating that separate mechanisms underlie the psychomotor and rewarding effects of cocaine. PMID:21806802

  6. Oxytocin decreases cocaine taking, cocaine seeking, and locomotor activity in female rats.

    Science.gov (United States)

    Leong, Kah-Chung; Zhou, Luyi; Ghee, Shannon M; See, Ronald E; Reichel, Carmela M

    2016-02-01

    Oxytocin has been shown to decrease cocaine taking and seeking in male rats, suggesting potential treatment efficacy for drug addiction. In the present study, we extended these findings to the assessment of cocaine seeking and taking in female rats. Further, we made direct comparisons of oxytocin's impact on cocaine induced locomotor activity in both males and females. In females, systemic oxytocin (0.3, 1.0, 3.0 mg/kg) attenuated lever pressing for cocaine during self-administration and oxytocin (1.0 mg/kg) attenuated cue-induced cocaine seeking following extinction. Cocaine increased baseline locomotor activity to a greater degree in females relative to males. Oxytocin (0.1, 0.3, 1.0, and 3.0 mg/kg) reduced cocaine-induced locomotor activity in females, but not significantly in males. These data illustrate sex similarities in oxytocin's attenuation of cocaine seeking, but sex differences in cocaine-induced locomotor effects. While reductions in cocaine seeking cannot be attributed to a reduction in locomotor activity in males, attenuation of locomotor function cannot be entirely ruled out as an explanation for a decrease in cocaine seeking in females suggesting that oxytocin's effect on cocaine seeking may be mediated by different mechanisms in male and females. PsycINFO Database Record (c) 2016 APA, all rights reserved.

  7. Clinical Holistic Medicine: Chronic Pain in the Locomotor System

    Directory of Open Access Journals (Sweden)

    Søren Ventegodt

    2005-01-01

    Full Text Available Most pains from the locomotor system arise due to involuntary, chronic tensions in the muscles or other tissues. When the patient is motivated, the pain is easily cured in most of the cases by using the tools of consciousness-based medicine, primarily therapeutic touch, conversation, and coaching the patient in a positive philosophy of life. The pains are often caused by “blockages” that may cause problems other than just pain. Often it turns out that the blocked areas develop actual physical damage over time: a slipped disk in the back, articular degeneration, or osteoarthritis when the cartilage is affected, can often be explained in this way. Apparently, the exact areas where the blockage is situated cause cellular problems, disrupting cellular order. The holistic process theory of healing and the related quality of life theories state that return to the natural state of being is possible, whenever the person gets the resources needed for existential healing. The resources needed are “holding” in the dimensions of awareness, respect, care, acknowledgment, and acceptance with support and processing in the dimensions of feeling, understanding, and letting go of negative attitudes and beliefs. The preconditions for holistic healing are trust and the intention for the healing to take place. Case stories of holistic treatment of patients with chronic back pain, low back pain, muscle problems, knee pain, and symptoms of rheumatoid arthritis are discussed with exercises relevant for patients with these conditions in the holistic clinic.

  8. Limitations imposed by wearing armour on Medieval soldiers' locomotor performance.

    Science.gov (United States)

    Askew, Graham N; Formenti, Federico; Minetti, Alberto E

    2012-02-22

    In Medieval Europe, soldiers wore steel plate armour for protection during warfare. Armour design reflected a trade-off between protection and mobility it offered the wearer. By the fifteenth century, a typical suit of field armour weighed between 30 and 50 kg and was distributed over the entire body. How much wearing armour affected Medieval soldiers' locomotor energetics and biomechanics is unknown. We investigated the mechanics and the energetic cost of locomotion in armour, and determined the effects on physical performance. We found that the net cost of locomotion (C(met)) during armoured walking and running is much more energetically expensive than unloaded locomotion. C(met) for locomotion in armour was 2.1-2.3 times higher for walking, and 1.9 times higher for running when compared with C(met) for unloaded locomotion at the same speed. An important component of the increased energy use results from the extra force that must be generated to support the additional mass. However, the energetic cost of locomotion in armour was also much higher than equivalent trunk loading. This additional cost is mostly explained by the increased energy required to swing the limbs and impaired breathing. Our findings can predict age-associated decline in Medieval soldiers' physical performance, and have potential implications in understanding the outcomes of past European military battles.

  9. Brandishing Cyberattack Capabilities

    Science.gov (United States)

    2013-01-01

    Advertising cyberwar capabilities may be helpful. It may back up a deterrence strategy. It might dissuade other states from conventional mischief or...to enable the attack.5 Many of the instruments of the attack remain with the target system, nestled in its log files, or even in the malware itself...debat- able. Even if demonstrated, what worked yesterday may not work today. But difficult does not mean impossible. Advertising cyberwar capabilities

  10. CASL Dakota Capabilities Summary

    Energy Technology Data Exchange (ETDEWEB)

    Adams, Brian M. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Simmons, Chris [Univ. of Texas, Austin, TX (United States); Williams, Brian J. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2017-10-10

    The Dakota software project serves the mission of Sandia National Laboratories and supports a worldwide user community by delivering state-of-the-art research and robust, usable software for optimization and uncertainty quantification. These capabilities enable advanced exploration and riskinformed prediction with a wide range of computational science and engineering models. Dakota is the verification and validation (V&V) / uncertainty quantification (UQ) software delivery vehicle for CASL, allowing analysts across focus areas to apply these capabilities to myriad nuclear engineering analyses.

  11. Conceptualizing innovation capabilities: A contingency perspective

    Directory of Open Access Journals (Sweden)

    Tor Helge Aas

    2017-01-01

    Full Text Available Empirical research has confirmed that a positive relationship exists between the implementation of innovation activities and the future performance of organizations. Firms utilize resources and capabilities to develop innovations in the form of new products, services or processes. Some firms prove to be better at reproducing innovation success than others, and the capacity to do so is referred to as innovation capability. However, the term innovation capability is ambiguously treated in extant literature. There are several different definitions of the concept and the distinction between innovation capabilities and other types of capabilities, such as dynamic capabilities, is neither explicitly stated, nor is the relationship between the concept and other resource- and capability-based concepts within strategy theory established. Although innovation is increasingly identified as crucial for a firm’s sustainable competitiveness in contemporary volatile and complex markets, the strategy-innovation link is underdeveloped in extant research. To overcome this challenge this paper raises the following research question: What type of innovation capabilities are required to innovate successfully? Due to the status of the extant research, we chose a conceptual research design to answer our research question and the paper contributes with a conceptual framework to discuss what innovation capabilities firms need to reproduce innovation success. Based on careful examination of current literature on innovation capability specifically, and the strategy-innovation link in general, we suggest that innovation capability must be viewed along two dimensions – innovation novelty and market characteristics. This framework enables the identification of four different contexts for innovation capabilities in a two-bytwo matrix. We discuss the types of innovation capabilities necessary within the four different contexts. This novel framework contributes to the

  12. Space Logistics: Launch Capabilities

    Science.gov (United States)

    Furnas, Randall B.

    1989-01-01

    The current maximum launch capability for the United States are shown. The predicted Earth-to-orbit requirements for the United States are presented. Contrasting the two indicates the strong National need for a major increase in Earth-to-orbit lift capability. Approximate weights for planned payloads are shown. NASA is studying the following options to meet the need for a new heavy-lift capability by mid to late 1990's: (1) Shuttle-C for near term (include growth versions); and (2) the Advanced Lauching System (ALS) for the long term. The current baseline two-engine Shuttle-C has a 15 x 82 ft payload bay and an expected lift capability of 82,000 lb to Low Earth Orbit. Several options are being considered which have expanded diameter payload bays. A three-engine Shuttle-C with an expected lift of 145,000 lb to LEO is being evaluated as well. The Advanced Launch System (ALS) is a potential joint development between the Air Force and NASA. This program is focused toward long-term launch requirements, specifically beyond the year 2000. The basic approach is to develop a family of vehicles with the same high reliability as the Shuttle system, yet offering a much greater lift capability at a greatly reduced cost (per pound of payload). The ALS unmanned family of vehicles will provide a low end lift capability equivalent to Titan IV, and a high end lift capability greater than the Soviet Energia if requirements for such a high-end vehicle are defined.In conclusion, the planning of the next generation space telescope should not be constrained to the current launch vehicles. New vehicle designs will be driven by the needs of anticipated heavy users.

  13. Campus Capability Plan

    Energy Technology Data Exchange (ETDEWEB)

    Adams, C. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Arsenlis, T. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Bailey, A. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Bergman, M. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Brase, J. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Brenner, J. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Camara, L. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Carlton, H. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Cheng, J. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Chrzanowski, P. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Colson, J. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); East, D. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Farrell, J. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Ferranti, L. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Gursahani, A. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Hansen, R. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Helms, L. L. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Hernandez, M. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Jeffries, J. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Larson, D. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Lu, K. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); McNabb, D. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Mercer, M. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Skeate, M. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Sueksdorf, M. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Zucca, B. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Le, D. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Ancria, R. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Scott, J. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Leininger, L. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Gagliardi, F. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Gash, A. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Bronson, M. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Chung, B. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Hobson, B. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Meeker, J. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Sanchez, J. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Zagar, M. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Quivey, B. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Sommer, S. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Atherton, J. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

    2017-06-06

    Lawrence Livermore National Laboratory Campus Capability Plan for 2018-2028. Lawrence Livermore National Laboratory (LLNL) is one of three national laboratories that are part of the National Nuclear Security Administration. LLNL provides critical expertise to strengthen U.S. security through development and application of world-class science and technology that: Ensures the safety, reliability, and performance of the U.S. nuclear weapons stockpile; Promotes international nuclear safety and nonproliferation; Reduces global danger from weapons of mass destruction; Supports U.S. leadership in science and technology. Essential to the execution and continued advancement of these mission areas are responsive infrastructure capabilities. This report showcases each LLNL capability area and describes the mission, science, and technology efforts enabled by LLNL infrastructure, as well as future infrastructure plans.

  14. Technological Capability's Predictor Variables

    Directory of Open Access Journals (Sweden)

    Fernanda Maciel Reichert

    2011-03-01

    Full Text Available The aim of this study was to identify the factors that influence in configuration of the technological capability of companies in sectors with medium-low technological intensity. To achieve the goal proposed in this article a survey was carried out. Based on the framework developed by Lall (1992 which classifies firms in basic, intermediate and advanced level of technological capability; it was found that the predominant technological capability is intermediate, with 83.7% of respondent companies (plastics companies in Brazil. It is believed that the main contribution of this study is the finding that the dependent variable named “Technological Capability” can be explained at a rate of 65% by six variables: development of new processes; selection of the best equipment supplier; sales of internally developed new technology to third parties; design and manufacture of equipment; study of the work methods and perform inventory control; and improvement of product quality.

  15. Effects of simultaneous exposure to stress and nicotine on nicotine-induced locomotor activation in adolescent and adult rats

    Directory of Open Access Journals (Sweden)

    A. Zago

    2012-01-01

    Full Text Available Preclinical studies have shown that repeated stress experiences can result in an increase in the locomotor response to the subsequent administration of drugs of abuse, a phenomenon that has been termed behavioral cross-sensitization. Behavioral sensitization reflects neuroadaptive processes associated with drug addiction and drug-induced psychosis. Although cross-sensitization between stress- and drug-induced locomotor activity has been clearly demonstrated in adult rats, few studies have evaluated this phenomenon in adolescent rats. In the present study, we determined if the simultaneous exposure to stress and nicotine was capable of inducing behavioral sensitization to nicotine in adolescent and adult rats. To this end, adolescent (postnatal day (P 28-37 and adult (P60-67 rats received nicotine (0.4 mg/kg, sc or saline (0.9% NaCl, sc and were immediately subjected to restraint stress for 2 h once a day for 7 days. The control group for stress was undisturbed following nicotine or saline injections. Three days after the last exposure to stress and nicotine, rats were challenged with a single dose of nicotine (0.4 mg/kg, sc or saline and nicotine-induced locomotion was then recorded for 30 min. In adolescent rats, nicotine caused behavioral sensitization only in animals that were simultaneously exposed to stress, while in adult rats nicotine promoted sensitization independently of stress exposure. These findings demonstrate that adolescent rats are more vulnerable to the effects of stress on behavioral sensitization to nicotine than adult rats.

  16. Human push capability.

    Science.gov (United States)

    Barnett, Ralph L; Liber, Theodore

    2006-02-22

    Use of unassisted human push capability arises from time to time in the areas of crowd and animal control, the security of locked doors, the integrity of railings, the removal of tree stumps and entrenched vehicles, the manoeuvering of furniture, and athletic pursuits such as US football or wrestling. Depending on the scenario, human push capability involves strength, weight, weight distribution, push angle, footwear/floor friction, and the friction between the upper body and the pushed object. Simple models are used to establish the relationships among these factors.

  17. The Capability Approach

    OpenAIRE

    Robeyns, Ingrid

    2011-01-01

    textabstract In its most general description, the capability approach is a flexible and multi-purpose normative framework, rather than a precise theory of well-being, freedom or justice. At its core are two normative claims: first, the claim that the freedom to achieve well-being is of primary moral importance, and second, that freedom to achieve well-being is to be understood in terms of people’s capabilities, that is, their real opportunities to do and be what they have reason to value. Thi...

  18. Sandia QIS Capabilities.

    Energy Technology Data Exchange (ETDEWEB)

    Muller, Richard P. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2017-07-01

    Sandia National Laboratories has developed a broad set of capabilities in quantum information science (QIS), including elements of quantum computing, quantum communications, and quantum sensing. The Sandia QIS program is built atop unique DOE investments at the laboratories, including the MESA microelectronics fabrication facility, the Center for Integrated Nanotechnologies (CINT) facilities (joint with LANL), the Ion Beam Laboratory, and ASC High Performance Computing (HPC) facilities. Sandia has invested $75 M of LDRD funding over 12 years to develop unique, differentiating capabilities that leverage these DOE infrastructure investments.

  19. Locomotor damage in rats after x-irradiation in Utero

    International Nuclear Information System (INIS)

    Mullenix, P.; Norton, S.; Culver, B.

    1975-01-01

    Alterations in gait were found in rats after whole-body irradiation with 125 R on day 14, 15, and 16 of gestation. No effects on locomotion were detected after irradiation on day 17 with 125 R or after irradiation on day 14 with 50 R. A technique was set up for quantitative evaluation of locomotion based on a modification of other methods. Walking patterns of irradiated rats were recorded, when they were adults, by requiring them to walk up a 10 0 incline through a corridor after their feet had been dipped in ink. Rats irradiated on gestational day 14 had an in-phase, hopping gait with the sine of the angle between the hind feet and the direction of progression over 0.9. Rats irradiated on gestational days 15 and 16 had an alternating, waddling gait with wider stance and broader angle than control rats. Histologic examination of serial sections of the brains of these rats showed that the 14-day rats lacked all telencephalic commissures except for a few fibers which crossed in some rats. There was a progressive improvement in the condition of the anterior and ventral hippocampal commissures up to day 17, but the corpus callosum and doral hippocampal commissure were lacking or markedly reduced in all day 17 rats. No animals showed damage to the mesencephalic posterior commissure. Since rats which used the in-phase mode of locomotion were never observed to use alternating gait, the possible causal relationship of the commissural damage to the altered locomotor patterns was considered. In view of the restricted period of damage found for the anterior and ventral hippocampal commissures and the restriction of altered locomotion to damage in the same period, primary involvement of the corpus callosum and dorsal hippocampal commissure could be excluded, but a possible role for the other telencephalic commissures remained

  20. General and Specific Strategies Used to Facilitate Locomotor Maneuvers.

    Directory of Open Access Journals (Sweden)

    Mengnan Wu

    Full Text Available People make anticipatory changes in gait patterns prior to initiating a rapid change of direction. How they prepare will change based on their knowledge of the maneuver. To investigate specific and general strategies used to facilitate locomotor maneuvers, we manipulated subjects' ability to anticipate the direction of an upcoming lateral "lane-change" maneuver. To examine specific anticipatory adjustments, we observed the four steps immediately preceding a maneuver that subjects were instructed to perform at a known time in a known direction. We hypothesized that to facilitate a specific change of direction, subjects would proactively decrease margin of stability in the future direction of travel. Our results support this hypothesis: subjects significantly decreased lateral margin of stability by 69% on the side ipsilateral to the maneuver during only the step immediately preceding the maneuver. This gait adaptation may have improved energetic efficiency and simplified the control of the maneuver. To examine general anticipatory adjustments, we observed the two steps immediately preceding the instant when subjects received information about the direction of the maneuver. When the maneuver direction was unknown, we hypothesized that subjects would make general anticipatory adjustments that would improve their ability to actively initiate a maneuver in multiple directions. This second hypothesis was partially supported as subjects increased step width and stance phase hip flexion during these anticipatory steps. These modifications may have improved subjects' ability to generate forces in multiple directions and maintain equilibrium during the onset and execution of the rapid maneuver. However, adapting these general anticipatory strategies likely incurred an additional energetic cost.

  1. A stochastic locomotor control model for the nurse shark, Ginglymostoma cirratum.

    Science.gov (United States)

    Gerald, K B; Matis, J H; Kleerekoper, H

    1978-06-12

    The locomotor behavior of the nurse shark (Ginglymostoma cirratum) is characterized by 17 variables (frequency and ratios of left, right, and total turns; their radians; straight paths (steps); distance travelled; and velocity) Within each of these variables there is an internal time dependency the structure of which was elaborated together with an improved statistical model predicting their behavior within 90% confidence limits. The model allows for the sensitive detection of subtle locomotor response to sensory stimulation as values of variables may exceed the established confidence limits within minutes after onset of the stimulus. The locomotor activity is well described by an autoregression time series model and can be predicted by only seven variables. Six of these form two independently operating clusters. The first one consists of: the number of right turns, the distance travelled and the mean velocity; the second one of: the mean size of right turns, of left turns, and of all turns. The same clustering is obtained independently by a cluster analysis of cross-sections of the seven time series. It is apparent that, among a total of 17 locomotor variables, seven behave as individually independent agents, presumably controlled by seven separate and independent centers. The output of each center can only be predicted by its own behavior. In spite of the individual of the seven variables, their internal structure is similar in important aspects which may result from control by a common command center. The shark locomotor model differs in important aspects from the previously constructed for the goldfish. The interdependence of the locomotor variables in both species may be related to the control mechanisms postulated by von Holst for the coordination of rhythmic fin movements in fishes. A locomotor control model for the nurse shark is proposed.

  2. Objective and quantitative equilibriometric evaluation of individual locomotor behaviour in schizophrenia: Translational and clinical implications.

    Science.gov (United States)

    Haralanov, Svetlozar; Haralanova, Evelina; Milushev, Emil; Shkodrova, Diana; Claussen, Claus-Frenz

    2018-04-17

    Psychiatry is the only medical specialty that lacks clinically applicable biomarkers for objective evaluation of the existing pathology at a single-patient level. On the basis of an original translational equilibriometric method for evaluation of movement patterns, we have introduced in the everyday clinical practice of psychiatry an easy-to-perform computerized objective quantification of the individual locomotor behaviour during execution of the Unterberger stepping test. For the last 20 years, we have gradually collected a large database of more than 1000 schizophrenic patients, their relatives, and matched psychiatric, neurological, and healthy controls via cross-sectional and longitudinal investigations. Comparative analyses revealed transdiagnostic locomotor similarities among schizophrenic patients, high-risk schizotaxic individuals, and neurological patients with multiple sclerosis and cerebellar ataxia, thus suggesting common underlying brain mechanisms. In parallel, intradiagnostic dissimilarities were revealed, which allow to separate out subclinical locomotor subgroups within the diagnostic categories. Prototypical qualitative (dysmetric and ataxic) locomotor abnormalities in schizophrenic patients were differentiated from 2 atypical quantitative ones, manifested as either hypolocomotion or hyperlocomotion. Theoretical analyses suggested that these 3 subtypes of locomotor abnormalities could be conceived as objectively measurable biomarkers of 3 schizophrenic subgroups with dissimilar brain mechanisms, which require different treatment strategies. Analogies with the prominent role of locomotor measures in some well-known animal models of mental disorders advocate for a promising objective translational research in the so far over-subjective field of psychiatry. Distinctions among prototypical, atypical, and diagnostic biomarkers, as well as between neuromotor and psychomotor locomotor abnormalities, are discussed. Conclusions are drawn about the

  3. Determinants of locomotor disability in people aged 55 years and over: The Rotterdam study

    International Nuclear Information System (INIS)

    Odding, Else; Valkenburg, Hans A.; Stam, Hendrik J.; Hofman, Albert

    2001-01-01

    Locomotor disability, as defined by difficulties in activities of daily living related to lower limb function, can be the consequence of diseases and impairments of the cardiovascular, pulmonary, nervous, sensory and musculoskeletal system. We estimated the associations between specific diseases and impairments and locomotor disability, and the proportion of disability attributable to each condition, controlling for age and comorbidity. The Rotterdam Study is a prospective follow-up study among people aged 55 years and over in the general population. Locomotor disability in 1219 men and 1856 women was assessed with the Stanford Health Assessment Questionnaire. Diseases and impairments were radiological osteoarthritis, pain of the hips and knees, morning stiffness, fractures, hypertension, vascular disease, ischemic heart disease, stroke, heart failure, chronic obstructive pulmonary disease (COPD), depression, Parkinson's disease, osteoporosis, diabetes mellitus, overweight, and low vision. Adjusted odds ratios, etiologic and attributable fractions were calculated for locomotor disability. The occurrence of locomotor disability can partly be ascribed to joint pain, COPD, morning stiffness, diabetes and heart failure in both men and women. In addition in women osteoarthritis, osteoporosis, low vision, fractures, stroke and Parkinson's disease are significant etiologic fractions. In men with morning stiffness, joint pain, heart failure, diabetes mellitus, and COPD a significant proportion of their disability is attributable to this impairment. In women this was the case for Parkinson's disease, morning stiffness, low vision, heart failure, joint pain, diabetes, radiological osteoarthritis, stroke, COPD, osteoporosis, and fractures of the lower limbs, in that order. We conclude that locomotor complaints, heart failure, COPD and diabetes mellitus contribute considerably to locomotor disability in non-institutionalized elderly people

  4. The Effects of Sex-Ratio and Density on Locomotor Activity in the House Fly, Musca domestica

    OpenAIRE

    Bahrndorff, Simon; Kjærsgaard, Anders; Pertoldi, Cino; Loeschcke, Volker; Schou, Toke M.; Skovgård, Henrik; Hald, Birthe

    2012-01-01

    Although locomotor activity is involved in almost all behavioral traits, there is a lack of knowledge on what factors affect it. This study examined the effects of sex-ratio and density on the circadian rhythm of locomotor activity of adult Musca domestica L. (Diptera: Muscidae) using an infra-red light system. Sex-ratio significantly affected locomotor activity, increasing with the percentage of males in the vials. In accordance with other studies, males were more active than females, but th...

  5. ISOPHOT - Capabilities and performance

    DEFF Research Database (Denmark)

    Lemke, D.; Klaas, U.; Abolins, J.

    1996-01-01

    ISOPHOT covers the largest wavelength range on ISO from 2.5 to 240 mu m. Its scientific capabilities include multi filter and multi-aperture photometry, polarimetry, imaging and spectrophotometry. All modes can optionally include a focal plane chopper. The backbone of the photometric calibration...

  6. Capabilities for Intercultural Dialogue

    Science.gov (United States)

    Crosbie, Veronica

    2014-01-01

    The capabilities approach offers a valuable analytical lens for exploring the challenge and complexity of intercultural dialogue in contemporary settings. The central tenets of the approach, developed by Amartya Sen and Martha Nussbaum, involve a set of humanistic goals including the recognition that development is a process whereby people's…

  7. Capabilities and Special Needs

    DEFF Research Database (Denmark)

    Kjeldsen, Christian Christrup

    into international consideration in relation to the implementation of the UN convention on the rights of persons with disabilities. As for the theoretical basis, the research makes use of the sociological open-ended and relational concepts of Pierre Bourdieu and the normative yardstick of the Capability Approach...

  8. Metrology Measurement Capabilities

    Energy Technology Data Exchange (ETDEWEB)

    Dr. Glen E. Gronniger

    2007-10-02

    This document contains descriptions of Federal Manufacturing & Technologies (FM&T) Metrology capabilities, traceability flow charts, and the measurement uncertainty of each measurement capability. Metrology provides NIST traceable precision measurements or equipment calibration for a wide variety of parameters, ranges, and state-of-the-art uncertainties. Metrology laboratories conform to the requirements of the Department of Energy Development and Production Manual Chapter 13.2, ANSI/ISO/IEC ANSI/ISO/IEC 17025:2005, and ANSI/NCSL Z540-1. FM&T Metrology laboratories are accredited by NVLAP for the parameters, ranges, and uncertainties listed in the specific scope of accreditation under NVLAP Lab code 200108-0. See the Internet at http://ts.nist.gov/Standards/scopes/2001080.pdf. These parameters are summarized. The Honeywell Federal Manufacturing & Technologies (FM&T) Metrology Department has developed measurement technology and calibration capability in four major fields of measurement: (1) Mechanical; (2) Environmental, Gas, Liquid; (3) Electrical (DC, AC, RF/Microwave); and (4) Optical and Radiation. Metrology Engineering provides the expertise to develop measurement capabilities for virtually any type of measurement in the fields listed above. A strong audit function has been developed to provide a means to evaluate the calibration programs of our suppliers and internal calibration organizations. Evaluation includes measurement audits and technical surveys.

  9. The Capability Approach

    NARCIS (Netherlands)

    I.A.M. Robeyns (Ingrid)

    2011-01-01

    textabstract In its most general description, the capability approach is a flexible and multi-purpose normative framework, rather than a precise theory of well-being, freedom or justice. At its core are two normative claims: first, the claim that the freedom to achieve well-being is of primary

  10. Sensor Alerting Capability

    Science.gov (United States)

    Henriksson, Jakob; Bermudez, Luis; Satapathy, Goutam

    2013-04-01

    There is a large amount of sensor data generated today by various sensors, from in-situ buoys to mobile underwater gliders. Providing sensor data to the users through standardized services, language and data model is the promise of OGC's Sensor Web Enablement (SWE) initiative. As the amount of data grows it is becoming difficult for data providers, planners and managers to ensure reliability of data and services and to monitor critical data changes. Intelligent Automation Inc. (IAI) is developing a net-centric alerting capability to address these issues. The capability is built on Sensor Observation Services (SOSs), which is used to collect and monitor sensor data. The alerts can be configured at the service level and at the sensor data level. For example it can alert for irregular data delivery events or a geo-temporal statistic of sensor data crossing a preset threshold. The capability provides multiple delivery mechanisms and protocols, including traditional techniques such as email and RSS. With this capability decision makers can monitor their assets and data streams, correct failures or be alerted about a coming phenomena.

  11. Capabilities and Equality of Health II

    DEFF Research Database (Denmark)

    Keiding, Hans

    The concept of capabilities, introduced originally by Sen, has inspired many researchers but has not found any simple formal representation which might be instrumental in the construction of a comprehensive theory of equality. In a previous paper (Keiding, 2005), we investigated whether preferences...... of the capability approach to questions of health or equality. In the present paper we extend the notion of rationalizing orderings of capabilities to a dynamical context, in the sense that the utility function is not yet revealed to the individual at the time when the capabilities are ordered. It turns out...... over capabilities as sets of functionings can be rationalized by maximization of a suitable utility function over the set of functionings. Such a rationalization turned out to be possible only in cases which must be considered exceptional and which do not allowfor interesting applications...

  12. Capitalizing on capabilities.

    Science.gov (United States)

    Ulrich, Dave; Smallwood, Norm

    2004-06-01

    By making the most of organizational capabilities--employees' collective skills and fields of expertise--you can dramatically improve your company's market value. Although there is no magic list of proficiencies that every organization needs in order to succeed, the authors identify 11 intangible assets that well-managed companies tend to have: talent, speed, shared mind-set and coherent brand identity, accountability, collaboration, learning, leadership, customer connectivity, strategic unity, innovation, and efficiency. Such companies typically excel in only three of these capabilities while maintaining industry parity in the other areas. Organizations that fall below the norm in any of the 11 are likely candidates for dysfunction and competitive disadvantage. So you can determine how your company fares in these categories (or others, if the generic list doesn't suit your needs), the authors explain how to conduct a "capabilities audit," describing in particular the experiences and findings of two companies that recently performed such audits. In addition to highlighting which intangible assets are most important given the organization's history and strategy, this exercise will gauge how well your company delivers on its capabilities and will guide you in developing an action plan for improvement. A capabilities audit can work for an entire organization, a business unit, or a region--indeed, for any part of a company that has a strategy to generate financial or customer-related results. It enables executives to assess overall company strengths and weaknesses, senior leaders to define strategy, midlevel managers to execute strategy, and frontline leaders to achieve tactical results. In short, it helps turn intangible assets into concrete strengths.

  13. High Throughput Measurement of Locomotor Sensitization to Volatilized Cocaine in Drosophila melanogaster.

    Science.gov (United States)

    Filošević, Ana; Al-Samarai, Sabina; Andretić Waldowski, Rozi

    2018-01-01

    Drosophila melanogaster can be used to identify genes with novel functional roles in neuronal plasticity induced by repeated consumption of addictive drugs. Behavioral sensitization is a relatively simple behavioral output of plastic changes that occur in the brain after repeated exposures to drugs of abuse. The development of screening procedures for genes that control behavioral sensitization has stalled due to a lack of high-throughput behavioral tests that can be used in genetically tractable organism, such as Drosophila . We have developed a new behavioral test, FlyBong, which combines delivery of volatilized cocaine (vCOC) to individually housed flies with objective quantification of their locomotor activity. There are two main advantages of FlyBong: it is high-throughput and it allows for comparisons of locomotor activity of individual flies before and after single or multiple exposures. At the population level, exposure to vCOC leads to transient and concentration-dependent increase in locomotor activity, representing sensitivity to an acute dose. A second exposure leads to further increase in locomotion, representing locomotor sensitization. We validate FlyBong by showing that locomotor sensitization at either the population or individual level is absent in the mutants for circadian genes period (per) , Clock (Clk) , and cycle (cyc) . The locomotor sensitization that is present in timeless (tim) and pigment dispersing factor (pdf) mutant flies is in large part not cocaine specific, but derived from increased sensitivity to warm air. Circadian genes are not only integral part of the neural mechanism that is required for development of locomotor sensitization, but in addition, they modulate the intensity of locomotor sensitization as a function of the time of day. Motor-activating effects of cocaine are sexually dimorphic and require a functional dopaminergic transporter. FlyBong is a new and improved method for inducing and measuring locomotor sensitization

  14. High Throughput Measurement of Locomotor Sensitization to Volatilized Cocaine in Drosophila melanogaster

    Directory of Open Access Journals (Sweden)

    Ana Filošević

    2018-02-01

    Full Text Available Drosophila melanogaster can be used to identify genes with novel functional roles in neuronal plasticity induced by repeated consumption of addictive drugs. Behavioral sensitization is a relatively simple behavioral output of plastic changes that occur in the brain after repeated exposures to drugs of abuse. The development of screening procedures for genes that control behavioral sensitization has stalled due to a lack of high-throughput behavioral tests that can be used in genetically tractable organism, such as Drosophila. We have developed a new behavioral test, FlyBong, which combines delivery of volatilized cocaine (vCOC to individually housed flies with objective quantification of their locomotor activity. There are two main advantages of FlyBong: it is high-throughput and it allows for comparisons of locomotor activity of individual flies before and after single or multiple exposures. At the population level, exposure to vCOC leads to transient and concentration-dependent increase in locomotor activity, representing sensitivity to an acute dose. A second exposure leads to further increase in locomotion, representing locomotor sensitization. We validate FlyBong by showing that locomotor sensitization at either the population or individual level is absent in the mutants for circadian genes period (per, Clock (Clk, and cycle (cyc. The locomotor sensitization that is present in timeless (tim and pigment dispersing factor (pdf mutant flies is in large part not cocaine specific, but derived from increased sensitivity to warm air. Circadian genes are not only integral part of the neural mechanism that is required for development of locomotor sensitization, but in addition, they modulate the intensity of locomotor sensitization as a function of the time of day. Motor-activating effects of cocaine are sexually dimorphic and require a functional dopaminergic transporter. FlyBong is a new and improved method for inducing and measuring locomotor

  15. Motor unit recruitment patterns 1: responses to changes in locomotor velocity and incline.

    Science.gov (United States)

    Hodson-Tole, Emma F; Wakeling, James M

    2008-06-01

    Mammalian skeletal muscles are composed of a mixture of motor unit types, which contribute a range of mechanical and physiological properties to the muscle. For a muscle to effectively contribute to smooth, co-ordinated movement it must activate an appropriate number and combination of motor units to generate the required force over a suitable time period. Much evidence exists indicating that motor units are activated in an orderly fashion, from the slowest through to the fastest. A growing body of evidence, however, indicates that such a recruitment strategy does not always hold true. Here we investigate how motor unit recruitment patterns were influenced by changes in locomotor velocity and incline. Kinematics data and myoelectric signals were collected from three rat ankle extensor muscles during running on a treadmill at nine velocity and incline combinations. Wavelet and principal component analysis were used to simultaneously decompose the signals into time and frequency space. The relative frequency components of the signals were quantified during 20 time windows of a stride from each locomotor condition. Differences in signal frequency components existed between muscles and locomotor conditions. Faster locomotor velocities led to a relative increase in high frequency components, whereas greater inclines led to a relative increase in the low frequency components. These data were interpreted as representing changes in motor unit recruitment patterns in response to changes in the locomotor demand. Motor units were not always recruited in an orderly manner, indicating that recruitment is a multi-factorial phenomenon that is not yet fully understood.

  16. Osteological postcranial traits in hylid anurans indicate a morphological continuum between swimming and jumping locomotor modes.

    Science.gov (United States)

    Soliz, Mónica; Tulli, Maria J; Abdala, Virginia

    2017-03-01

    Anurans exhibit a particularly wide range of locomotor modes that result in wide variations in their skeletal structure. This article investigates the possible correlation between morphological aspects of the hylid postcranial skeleton and their different locomotor modes and habitat use. To do so, we analyzed 18 morphometric postcranial variables in 19 different anuran species representative of a variety of locomotor modes (jumper, hopper, walker, and swimmer) and habitat uses (arboreal, bush, terrestrial, and aquatic). Our results show that the evolution of the postcranial hylid skeleton cannot be explained by one single model, as for example, the girdles suggest modular evolution while the vertebral column suggests other evolutionary modules. In conjunction with data from several other studies, we were able to show a relationship between hylid morphology and habitat use; offering further evidence that the jumper/swimmer and walker/hopper locomotor modes exhibit quite similar morphological architecture. This allowed us to infer that new locomotor modalities are, in fact, generated along a morphological continuum. J. Morphol. 278:403-417, 2017. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

  17. Effect of thiamethoxam on cockroach locomotor activity is associated with its metabolite clothianidin.

    Science.gov (United States)

    Benzidane, Yassine; Touinsi, Sarra; Motte, Emilie; Jadas-Hécart, Alain; Communal, Pierre-Yves; Leduc, Lionel; Thany, Steeve H

    2010-12-01

    In the present study, the effect of thiamethoxam and clothianidin on the locomotor activity of American cockroach, Periplaneta americana (L.), was evaluated. Because it has been proposed that thiamethoxam is metabolised to clothianidin, high-performance liquid chromatography coupled with mass spectrometry was used to evaluate the amount of clothianidin on thiamethoxam-treated cockroaches. One hour after neonicotinoid treatment, the time spent in the open-field-like apparatus significantly increased, suggesting a decrease in locomotor activity. The percentage of cockroaches displaying locomotor activity was significantly reduced 1 h after haemolymph application of 1 nmol g(-1) neonicotinoid, while no significant effect was found after topical and oral administration. However, at 24 and 48 h, all neonicotinoids were able to reduce locomotor activity, depending on their concentrations and the way they were applied. Interestingly, it was found that thiamethoxam was converted to clothianidin 1 h after application, but the amount of clothianidin did not rise proportionately to thiamethoxam, especially after oral administration. The data suggest that the effect of thiamethoxam on cockroach locomotor activity is due in part to clothianidin action because (1) thiamethoxam levels remained persistent 48 h after application and (2) the amount of clothianidin in cockroach tissues was consistent with the toxicity of thiamethoxam. Copyright © 2010 Society of Chemical Industry.

  18. Effects of caffeine on locomotor activity in streptozotocin-induced diabetic rats.

    Science.gov (United States)

    Bădescu, S V; Tătaru, C P; Kobylinska, L; Georgescu, E L; Zahiu, D M; Zăgrean, A M; Zăgrean, L

    2016-01-01

    Diabetes mellitus modifies the expression of adenosine receptors in the brain. Caffeine acts as an antagonist of A1 and A2A adenosine receptors and was shown to have a dose-dependent biphasic effect on locomotion in mice. The present study investigated the link between diabetes and locomotor activity in an animal model of streptozotocin-induced diabetes, and the effects of a low-medium dose of caffeine in this relation. The locomotor activity was investigated by using Open Field Test at 6 weeks after diabetes induction and after 2 more weeks of chronic caffeine administration. Diabetes decreased locomotor activity (total distance moved and mobility time). Chronic caffeine exposure impaired the locomotor activity in control rats, but not in diabetic rats. Our data suggested that the medium doses of caffeine might block the A2A receptors, shown to have an increased density in the brain of diabetic rats, and improve or at least maintain the locomotor activity, offering a neuroprotective support in diabetic rats. Abbreviations : STZ = streptozotocin, OFT = Open Field Test.

  19. Using a Split-belt Treadmill to Evaluate Generalization of Human Locomotor Adaptation.

    Science.gov (United States)

    Vasudevan, Erin V L; Hamzey, Rami J; Kirk, Eileen M

    2017-08-23

    Understanding the mechanisms underlying locomotor learning helps researchers and clinicians optimize gait retraining as part of motor rehabilitation. However, studying human locomotor learning can be challenging. During infancy and childhood, the neuromuscular system is quite immature, and it is unlikely that locomotor learning during early stages of development is governed by the same mechanisms as in adulthood. By the time humans reach maturity, they are so proficient at walking that it is difficult to come up with a sufficiently novel task to study de novo locomotor learning. The split-belt treadmill, which has two belts that can drive each leg at a different speed, enables the study of both short- (i.e., immediate) and long-term (i.e., over minutes-days; a form of motor learning) gait modifications in response to a novel change in the walking environment. Individuals can easily be screened for previous exposure to the split-belt treadmill, thus ensuring that all experimental participants have no (or equivalent) prior experience. This paper describes a typical split-belt treadmill adaptation protocol that incorporates testing methods to quantify locomotor learning and generalization of this learning to other walking contexts. A discussion of important considerations for designing split-belt treadmill experiments follows, including factors like treadmill belt speeds, rest breaks, and distractors. Additionally, potential but understudied confounding variables (e.g., arm movements, prior experience) are considered in the discussion.

  20. Capabilities for managing service innovation: towards a conceptual framework

    NARCIS (Netherlands)

    den Hertog, P.; van der Aa, W.; de Jong, M.W.

    2010-01-01

    Purpose - The purpose of this paper is to identify and reflect on a set of dynamic capabilities for managing service innovation and applies a dynamic capabilities view (DCV) of firms for managing service innovation. Design/methodology/approach - This theoretical paper offers a conceptual framework

  1. Atmospheric Release Advisory Capability

    International Nuclear Information System (INIS)

    Dickerson, M.H.; Gudiksen, P.H.; Sullivan, T.J.

    1983-02-01

    The Atmospheric Release Advisory Capability (ARAC) project is a Department of Energy (DOE) sponsored real-time emergency response service available for use by both federal and state agencies in case of a potential or actual atmospheric release of nuclear material. The project, initiated in 1972, is currently evolving from the research and development phase to full operation. Plans are underway to expand the existing capability to continuous operation by 1984 and to establish a National ARAC Center (NARAC) by 1988. This report describes the ARAC system, its utilization during the past two years, and plans for its expansion during the next five to six years. An integral part of this expansion is due to a very important and crucial effort sponsored by the Defense Nuclear Agency to extend the ARAC service to approximately 45 Department of Defense (DOD) sites throughout the continental US over the next three years

  2. Group Capability Model

    Science.gov (United States)

    Olejarski, Michael; Appleton, Amy; Deltorchio, Stephen

    2009-01-01

    The Group Capability Model (GCM) is a software tool that allows an organization, from first line management to senior executive, to monitor and track the health (capability) of various groups in performing their contractual obligations. GCM calculates a Group Capability Index (GCI) by comparing actual head counts, certifications, and/or skills within a group. The model can also be used to simulate the effects of employee usage, training, and attrition on the GCI. A universal tool and common method was required due to the high risk of losing skills necessary to complete the Space Shuttle Program and meet the needs of the Constellation Program. During this transition from one space vehicle to another, the uncertainty among the critical skilled workforce is high and attrition has the potential to be unmanageable. GCM allows managers to establish requirements for their group in the form of head counts, certification requirements, or skills requirements. GCM then calculates a Group Capability Index (GCI), where a score of 1 indicates that the group is at the appropriate level; anything less than 1 indicates a potential for improvement. This shows the health of a group, both currently and over time. GCM accepts as input head count, certification needs, critical needs, competency needs, and competency critical needs. In addition, team members are categorized by years of experience, percentage of contribution, ex-members and their skills, availability, function, and in-work requirements. Outputs are several reports, including actual vs. required head count, actual vs. required certificates, CGI change over time (by month), and more. The program stores historical data for summary and historical reporting, which is done via an Excel spreadsheet that is color-coded to show health statistics at a glance. GCM has provided the Shuttle Ground Processing team with a quantifiable, repeatable approach to assessing and managing the skills in their organization. They now have a common

  3. Expeditionary Rubber Removal Capability

    Science.gov (United States)

    2006-12-31

    the modified spray unit or system with equivalent capabilities. 24 25 9.8. A pressure sensor or caster wheels should be incorporated into the...DISCUSSION 18 8.0 CONCLUSIONS 23 9.0 RECOMMENDATIONS 24 APPENDIX A – DETAILED LIST OF EQUIPMENT AND MODIFICATIONS 26 APPENDIX B – LIST OF SOURCES FOR...tall Weight – 4820 lb (No Attachments) Top Speed – 18 mph High Flow Hydraulics (Optional) – 26 gpm Steering – All Wheel Steering Cargo Max Load

  4. Atmospheric release advisory capability

    International Nuclear Information System (INIS)

    Sullivan, T.J.

    1981-01-01

    The ARAC system (Atmospheric Release Advisory Capability) is described. The system is a collection of people, computers, computer models, topographic data and meteorological input data that together permits a calculation of, in a quasi-predictive sense, where effluent from an accident will migrate through the atmosphere, where it will be deposited on the ground, and what instantaneous and integrated dose an exposed individual would receive

  5. Do social networks and technological capabilities help knowledge management?

    Directory of Open Access Journals (Sweden)

    Encarnación García-Sánchez

    2017-12-01

    Full Text Available Dynamic capabilities are currently becoming an important extension of the theory of resources and capabilities that enables companies to adapt better in the current competitive environment. This paper examines how knowledge management, a dynamic function related to management or administration of a set of knowledge flows, develops thanks to the greater dynamism of social networks. It then shows how this relationship is especially strengthened by different technological capabilities. To achieve these goals, the paper examines the main tools that permit companies to develop an ability to achieve competitive advantage relative to the technological capabilities of managers and workers, social networks and knowledge management.

  6. Locomotor circumvention strategies are altered by stroke: II. Postural Coordination.

    Science.gov (United States)

    Darekar, Anuja; Lamontagne, Anouk; Fung, Joyce

    2017-06-15

    Locomotor strategies for obstacle circumvention require appropriate postural coordination that depends on sensorimotor integration within the central nervous system. It is not known how these strategies are affected by a stroke. The objective of this study was to contrast postural coordination strategies used for obstacle circumvention between post-stroke participants (n = 12) and healthy controls (n = 12). Participants walked towards a target in a virtual environment (11 × 8 m room) with cylindrical obstacles that were stationary or approaching from head-on, or diagonally 30° left/right. Two stepping strategies for obstacle circumvention were identified: 1) side step: increase in step width by the foot ipsilateral to the side of circumvention; 2) cross step: decrease in step width by the foot contralateral to the side of circumvention. The side step strategy was favoured by post-stroke individuals in circumventing stationary and head-on approaching obstacles. In circumventing diagonally approaching obstacles, healthy controls generally veered opposite to obstacle approach (>60% trials), whereas the majority of post-stroke participants (7/12) veered to the same side of obstacle approach (V same ). Post-stroke participants who veered to the opposite side (V opp , 5/12) were more independent and faster ambulators who favoured the side step strategy in circumventing obstacles approaching from the paretic side and cross step strategy for obstacles approaching from the non-paretic side. V same participants generally favoured the side step strategy for both diagonal approaches. Segmental rotation amplitudes and latencies were largest in the V same group, and significantly greater in post-stroke participants than controls for all obstacle conditions. All participants initiated circumvention with the feet followed by the pelvis and thorax, demonstrating a caudal-rostral sequence of reorientation. Postural coordination strategies for obstacle circumvention

  7. Learning a locomotor task: with or without errors?

    Science.gov (United States)

    Marchal-Crespo, Laura; Schneider, Jasmin; Jaeger, Lukas; Riener, Robert

    2014-03-04

    Robotic haptic guidance is the most commonly used robotic training strategy to reduce performance errors while training. However, research on motor learning has emphasized that errors are a fundamental neural signal that drive motor adaptation. Thus, researchers have proposed robotic therapy algorithms that amplify movement errors rather than decrease them. However, to date, no study has analyzed with precision which training strategy is the most appropriate to learn an especially simple task. In this study, the impact of robotic training strategies that amplify or reduce errors on muscle activation and motor learning of a simple locomotor task was investigated in twenty two healthy subjects. The experiment was conducted with the MAgnetic Resonance COmpatible Stepper (MARCOS) a special robotic device developed for investigations in the MR scanner. The robot moved the dominant leg passively and the subject was requested to actively synchronize the non-dominant leg to achieve an alternating stepping-like movement. Learning with four different training strategies that reduce or amplify errors was evaluated: (i) Haptic guidance: errors were eliminated by passively moving the limbs, (ii) No guidance: no robot disturbances were presented, (iii) Error amplification: existing errors were amplified with repulsive forces, (iv) Noise disturbance: errors were evoked intentionally with a randomly-varying force disturbance on top of the no guidance strategy. Additionally, the activation of four lower limb muscles was measured by the means of surface electromyography (EMG). Strategies that reduce or do not amplify errors limit muscle activation during training and result in poor learning gains. Adding random disturbing forces during training seems to increase attention, and therefore improve motor learning. Error amplification seems to be the most suitable strategy for initially less skilled subjects, perhaps because subjects could better detect their errors and correct them

  8. A framework for offshore vendor capability development

    Science.gov (United States)

    Yusuf Wibisono, Yogi; Govindaraju, Rajesri; Irianto, Dradjad; Sudirman, Iman

    2016-02-01

    Offshore outsourcing is a common practice conducted by companies, especially in developed countries, by relocating one or more their business processes to other companies abroad, especially in developing countries. This practice grows rapidly owing to the ease of accessing qualified vendors with a lower cost. Vendors in developing countries compete more intensely to acquire offshore projects. Indonesia is still below India, China, Malaysia as main global offshore destinations. Vendor capability is among other factors that contribute to the inability of Indonesian vendor in competing with other companies in the global market. Therefore, it is essential to study how to increase the vendor's capability in Indonesia, in the context of global offshore outsourcing. Previous studies on the vendor's capability mainly focus on capabilities without considering the dynamic of capabilities due to the environmental changes. In order to be able to compete with competitors and maintain the competitive advantage, it is necessary for vendors to develop their capabilities continuously. The purpose of this study is to develop a framework that describes offshore vendor capability development along the client-vendor relationship stages. The framework consists of three main components, i.e. the stages of client-vendor relationship, the success of each stage, and the capabilities of vendor at each stage.

  9. Effects of noradrenaline on locomotor rhythm-generating networks in the isolated neonatal rat spinal cord

    DEFF Research Database (Denmark)

    Kiehn, O; Sillar, K T; Kjaerulff, O

    1999-01-01

    locomotor-like rhythm, in which activity alternated between the left and right sides, and between rostral and caudal roots on the same side. As shown previously, stable locomotor activity could be induced by bath application of N-methyl-D-aspartate (NMDA; 4-8.5 microM) and/or serotonin (5-HT; 4-20 micro......M). NA modulated this activity by decreasing the cycle frequency and increasing the ventral root burst duration. These effects were dose dependent in the concentration range 1-5 microM. In contrast, at no concentration tested did NA have consistent effects on burst amplitudes or on the background...... activity of the ongoing rhythm. Moreover, NA did not obviously affect the left/right and rostrocaudal alternation of the NMDA/5-HT rhythm. The NMDA/5-HT locomotor rhythm sometimes displayed a time-dependent breakdown in coordination, ultimately resulting in tonic ventral root activity. However...

  10. EphA4 defines a class of excitatory locomotor-related interneurons

    DEFF Research Database (Denmark)

    Butt, S. J B; Lundfald, Line; Kiehn, Ole

    2005-01-01

    of these interneurons provide direct excitation to ipsilateral motor neurons as determined by spike-triggered averaging of the local ventral root DC trace. Our findings substantiate the role of EphA4-positive interneurons as significant components of the ipsilateral locomotor network and describe a group of putative...... of the role of these cells in the network. One such marker is the EphA4 axon guidance receptor. EphA4-null mice display an abnormal rabbit-like hopping gait that is thought to be the result of synchronization of the normally alternating, bilateral locomotor network via aberrant crossed connections....... In this study, we have performed whole-cell patch clamp on EphA4-positive interneurons in the flexor region (L2) of the locomotor network. We provide evidence that although EphA4 positive interneurons are not entirely a homogeneous population, most of them fire in a rhythmic manner. Moreover, a subset...

  11. Locomotor muscle fatigue does not alter oxygen uptake kinetics during high-intensity exercise

    Directory of Open Access Journals (Sweden)

    James Hopker

    2016-10-01

    Full Text Available The slow component (VO2sc that develops during high-intensity aerobic exercise is thought to be strongly associated with locomotor muscle fatigue. We sought to experimentally test this hypothesis by pre-fatiguing the locomotor muscles used during subsequent high-intensity cycling exercise. Over two separate visits, eight healthy male participants were asked to either perform a non-metabolically stressful 100 intermittent drop-jumps protocol (pre fatigue condition or rest for 33 minutes (control condition according to a random and counterbalanced order. Locomotor muscle fatigue was quantified with 6-second maximal sprints at a fixed pedaling cadence of 90 rev·min-1. Oxygen kinetics and other responses (heart rate, capillary blood lactate concentration and rating of perceived exertion, RPE were measured during two subsequent bouts of 6 min cycling exercise at 50% of the delta between the lactate threshold and VO2max determined during a preliminary incremental exercise test. All tests were performed on the same cycle ergometer. Despite significant locomotor muscle fatigue (P = 0.03, the VO2sc was not significantly different between the pre fatigue (464 ± 301 mL·min-1 and the control (556 ± 223 mL·min-1 condition (P = 0.50. Blood lactate response was not significantly different between conditions (P = 0.48 but RPE was significantly higher following the pre-fatiguing exercise protocol compared with the control condition (P < 0.01 suggesting higher muscle recruitment. These results demonstrate experimentally that locomotor muscle fatigue does not significantly alter the VO2 kinetic response to high intensity aerobic exercise, and challenge the hypothesis that the VO2sc is strongly associated with locomotor muscle fatigue.

  12. Locomotor Muscle Fatigue Does Not Alter Oxygen Uptake Kinetics during High-Intensity Exercise.

    Science.gov (United States)

    Hopker, James G; Caporaso, Giuseppe; Azzalin, Andrea; Carpenter, Roger; Marcora, Samuele M

    2016-01-01

    The [Formula: see text] slow component ([Formula: see text]) that develops during high-intensity aerobic exercise is thought to be strongly associated with locomotor muscle fatigue. We sought to experimentally test this hypothesis by pre-fatiguing the locomotor muscles used during subsequent high-intensity cycling exercise. Over two separate visits, eight healthy male participants were asked to either perform a non-metabolically stressful 100 intermittent drop-jumps protocol (pre-fatigue condition) or rest for 33 min (control condition) according to a random and counterbalanced order. Locomotor muscle fatigue was quantified with 6-s maximal sprints at a fixed pedaling cadence of 90 rev·min -1 . Oxygen kinetics and other responses (heart rate, capillary blood lactate concentration and rating of perceived exertion, RPE) were measured during two subsequent bouts of 6 min cycling exercise at 50% of the delta between the lactate threshold and [Formula: see text] determined during a preliminary incremental exercise test. All tests were performed on the same cycle ergometer. Despite significant locomotor muscle fatigue ( P = 0.03), the [Formula: see text] was not significantly different between the pre-fatigue (464 ± 301 mL·min -1 ) and the control (556 ± 223 mL·min -1 ) condition ( P = 0.50). Blood lactate response was not significantly different between conditions ( P = 0.48) but RPE was significantly higher following the pre-fatiguing exercise protocol compared with the control condition ( P locomotor muscle fatigue does not significantly alter the [Formula: see text] kinetic response to high intensity aerobic exercise, and challenge the hypothesis that the [Formula: see text] is strongly associated with locomotor muscle fatigue.

  13. Potential contributions of training intensity on locomotor performance in individuals with chronic stroke.

    Science.gov (United States)

    Holleran, Carey L; Rodriguez, Kelly S; Echauz, Anthony; Leech, Kristan A; Hornby, T George

    2015-04-01

    Many interventions can improve walking ability of individuals with stroke, although the training parameters that maximize recovery are not clear. For example, the contribution of training intensity has not been well established and may contribute to the efficacy of many locomotor interventions. The purpose of this preliminary study was to evaluate the effects of locomotor training intensity on walking outcomes in individuals with gait deficits poststroke. Using a randomized cross-over design, 12 participants with chronic stroke (>6-month duration) performed either high-intensity (70%-80% of heart rate reserve; n = 6) or low-intensity (30%-40% heart rate reserve; n = 6) locomotor training for 12 or fewer sessions over 4 to 5 weeks. Four weeks following completion, the alternate training intervention was performed. Training intensity was manipulated by adding loads or applying resistance during walking, with similar speeds, durations, and amount of stepping practice between conditions. Greater increases in 6-Minute Walk Test performance were observed following high-intensity training compared with low-intensity training. A significant interaction of intensity and order was also observed for 6-Minute Walk Test and peak treadmill speed, with the largest changes in those who performed high-intensity training first. Moderate correlations were observed between locomotor outcomes and measures of training intensity. This study provides the first evidence that the intensity of locomotor practice may be an important independent determinant of walking outcomes poststroke. In the clinical setting, the intensity of locomotor training can be manipulated in many ways, although this represents only 1 parameter to consider.Video Abstract available for more insights from the authors (see Supplemental Digital Content 1, http://links.lww.com/JNPT/A90).

  14. Manipulation of dopamine metabolism contributes to attenuating innate high locomotor activity in ICR mice.

    Science.gov (United States)

    Yamaguchi, Takeshi; Nagasawa, Mao; Ikeda, Hiromi; Kodaira, Momoko; Minaminaka, Kimie; Chowdhury, Vishwajit S; Yasuo, Shinobu; Furuse, Mitsuhiro

    2017-06-15

    Attention-deficit hyperactivity disorder (ADHD) is defined as attention deficiency, restlessness and distraction. The main characteristics of ADHD are hyperactivity, impulsiveness and carelessness. There is a possibility that these abnormal behaviors, in particular hyperactivity, are derived from abnormal dopamine (DA) neurotransmission. To elucidate the mechanism of high locomotor activity, the relationship between innate activity levels and brain monoamines and amino acids was investigated in this study. Differences in locomotor activity between ICR, C57BL/6J and CBA/N mice were determined using the open field test. Among the three strains, ICR mice showed the greatest amount of locomotor activity. The level of striatal and cerebellar DA was lower in ICR mice than in C57BL/6J mice, while the level of L-tyrosine (L-Tyr), a DA precursor, was higher in ICR mice. These results suggest that the metabolic conversion of L-Tyr to DA is lower in ICR mice than it is in C57BL/6J mice. Next, the effects of intraperitoneal injection of (6R)-5, 6, 7, 8-tetrahydro-l-biopterin dihydrochloride (BH 4 ) (a co-enzyme for tyrosine hydroxylase) and L-3,4-dihydroxyphenylalanine (L-DOPA) on DA metabolism and behavior in ICR mice were investigated. The DA level in the brain was increased by BH 4 administration, but the increased DA did not influence behavior. However, L-DOPA administration drastically lowered locomotor activity and increased DA concentration in several parts of the brain. The reduced locomotor activity may have been a consequence of the overproduction of DA. In conclusion, the high level of locomotor activity in ICR mice may be explained by a strain-specific DA metabolism. Copyright © 2017 Elsevier B.V. All rights reserved.

  15. The evolution of alliance capabilities

    NARCIS (Netherlands)

    Heimeriks, K.H.; Duysters, G.M.; Vanhaverbeke, W.P.M.

    2004-01-01

    This paper assesses the effectiveness and differential performance effects of learning mechanisms on the evolution of alliance capabilities. Relying on the concept of capability lifecycles, prior research has suggested that different capability levels could be identified in which different

  16. Age-Related Changes in Locomotor Performance Reveal a Similar Pattern for Caenorhabditis elegans, Mus domesticus, Canis familiaris, Equus caballus, and Homo sapiens.

    Science.gov (United States)

    Marck, Adrien; Berthelot, Geoffroy; Foulonneau, Vincent; Marc, Andy; Antero-Jacquemin, Juliana; Noirez, Philippe; Bronikowski, Anne M; Morgan, Theodore J; Garland, Theodore; Carter, Patrick A; Hersen, Pascal; Di Meglio, Jean-Marc; Toussaint, Jean-François

    2017-04-01

    Locomotion is one of the major physiological functions for most animals. Previous studies have described aging mechanisms linked to locomotor performance among different species. However, the precise dynamics of these age-related changes, and their interactions with development and senescence, are largely unknown. Here, we use the same conceptual framework to describe locomotor performances in Caenorhabditis elegans, Mus domesticus, Canis familiaris, Equus caballus, and Homo sapiens. We show that locomotion is a consistent biomarker of age-related changes, with an asymmetrical pattern throughout life, regardless of the type of effort or its duration. However, there is variation (i) among species for the same mode of locomotion, (ii) within species for different modes of locomotion, and (iii) among individuals of the same species for the same mode of locomotion. Age-related patterns are modulated by genetic (such as selective breeding) as well as environmental conditions (such as temperature). However, in all cases, the intersection of the rising developmental phase and the declining senescent phase reveals neither a sharp transition nor a plateau, but a smooth transition, emphasizing a crucial moment: the age at peak performance. This transition may define a specific target for future investigations on the dynamics of such biological interactions. © The Author 2016. Published by Oxford University Press on behalf of The Gerontological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  17. Asymmetric operation of the locomotor central pattern generator in the neonatal mouse spinal cord

    DEFF Research Database (Denmark)

    Endo, Toshiaki; Kiehn, Ole

    2008-01-01

    The rhythmic voltage oscillations in motor neurons (MNs) during locomotor movements reflect the operation of the pre-MN central pattern generator (CPG) network. Recordings from MNs can thus be used as a method to deduct the organization of CPGs. Here, we use continuous conductance measurements...... of locomotor CPG. The extracted excitatory and inhibitory synaptic conductances varied between 2 and 56% of the mean total conductance. Analysis of the phase tuning of the extracted synaptic conductances in flexor and extensor MNs in the rostral lumbar cord showed that the flexor-phase-related synaptic...

  18. Plasticity of locomotor sensorimotor interactions after peripheral and/or spinal lesions

    DEFF Research Database (Denmark)

    Rossignol, Serge; Barrière, Grégory; Frigon, Alain

    2008-01-01

    The present paper reviews aspects of locomotor sensorimotor interactions by focussing on work performed in spinal cats. We provide a brief overview of spinal locomotion and describe the effects of various types of sensory deprivations (e.g. rhizotomies, and lesions of muscle and cutaneous nerves......) to highlight the spinal neuroplasticity necessary for adapting to sensory loss. Recent work on plastic interactions between reflex pathways that could be responsible for such plasticity, in particular changes in proprioceptive and cutaneous pathways that occur during locomotor training of spinal cats...

  19. Glutamatergic mechanisms for speed control and network operation in the rodent locomotor CPG

    DEFF Research Database (Denmark)

    Talpalar, Adolfo E.; Kiehn, Ole

    2010-01-01

    in mammals have produced conflicting results regarding the necessity and role of the different ionotropic glutamate receptors (GluRs) in the CPG function. Here, we use electrophysiological and pharmacological techniques in the in vitro neonatal mouse lumbar spinal cord to investigate the role of a broad...... mechanisms acting at various network levels. AMPA and kainate receptors are necessary for generating the highest locomotor frequencies. For coordination, NMDARs are more important than non-NMDARs for conveying the rhythmic signal from the network to the motor neurons during long-lasting and steady locomotor...

  20. Prenatal Iron Deficiency in Guinea Pigs Increases Locomotor Activity but Does Not Influence Learning and Memory

    OpenAIRE

    Fiset, Catherine; Rioux, France M.; Surette, Marc E.; Fiset, Sylvain

    2015-01-01

    The objective of the current study was to determine whether prenatal iron deficiency induced during gestation in guinea pigs affected locomotor activity and learning and memory processes in the progeny. Dams were fed either iron-deficient anemic or iron-sufficient diets throughout gestation and lactation. After weaning, all pups were fed an iron-sufficient diet. On postnatal day 24 and 40, the pups' locomotor activity was observed within an open-field test, and from postnatal day 25 to 40, th...

  1. Sleep pattern and locomotor activity are impaired by doxorubicin in non-tumor-bearing rats.

    Science.gov (United States)

    Lira, Fabio Santos; Esteves, Andrea Maculano; Pimentel, Gustavo Duarte; Rosa, José Cesar; Frank, Miriam Kannebley; Mariano, Melise Oliveira; Budni, Josiane; Quevedo, João; Santos, Ronaldo Vagner Dos; de Mello, Marco Túlio

    2016-01-01

    We sought explore the effects of doxorubicin on sleep patterns and locomotor activity. To investigate these effects, two groups were formed: a control group and a Doxorubicin (DOXO) group. Sixteen rats were randomly assigned to either the control or DOXO groups. The sleep patterns were examined by polysomnographic recording and locomotor activity was evaluated in an open-field test. In the light period, the total sleep time and slow wave sleep were decreased, while the wake after sleep onset and arousal were increased in the DOXO group compared with the control group (plocomotor activity.

  2. Efficacy of Stochastic Vestibular Stimulation to Improve Locomotor Performance in a Discordant Sensory Environment

    Science.gov (United States)

    Temple, D. R.; De Dios, Y. E.; Layne, C. S.; Bloomberg, J. J.; Mulavara, A. P.

    2016-01-01

    Astronauts exposed to microgravity face sensorimotor challenges incurred when readapting to a gravitational environment. Sensorimotor Adaptability (SA) training has been proposed as a countermeasure to improve locomotor performance during re-adaptation, and it is suggested that the benefits of SA training may be further enhanced by improving detection of weak sensory signals via mechanisms such as stochastic resonance when a non-zero level of stochastic white noise based electrical stimulation is applied to the vestibular system (stochastic vestibular stimulation, SVS). The purpose of this study was to test the efficacy of using SVS to improve short-term adaptation in a sensory discordant environment during performance of a locomotor task.

  3. Effect of physical exercise prelabyrinthectomy on locomotor balance compensation in the squirrel monkey

    Science.gov (United States)

    Igarashi, M.; Ohashi, K.; Yoshihara, T.; MacDonald, S.

    1989-01-01

    This study examines the effectiveness of physical exercise, during a prepathology state, on locomotor balance compensation after subsequent unilateral labyrinthectomy in squirrel monkeys. An experimental group underwent 3 hr. of daily running exercise on a treadmill for 3 mo. prior to the surgery, whereas a control group was not exercised. Postoperatively, the locomotor balance function of both groups was tested for 3 mo. There was no significant difference in gait deviation counts in the acute phase of compensation. However, in the chronic compensation maintenance phase, the number of gait deviation counts was fewer in the exercise group, which showed significantly better performance stability.

  4. Building Server Capabilities

    DEFF Research Database (Denmark)

    Adeyemi, Oluseyi

    2013-01-01

    Many western companies have moved part of their operations to China in order to take advantage of cheap resources and/or to gain access to a high potential market. Depending on motive, offshore facilities usually start either as “sales-only” of products exported by headquarters or “production......-only”, exporting parts and components back to headquarter for sales in the home country. In the course of time, the role of offshore subsidiaries in a company’s operations network tends to change and, with that, the capabilities, of the subsidiaries. Focusing on Danish subsidiaries in China, the objective...

  5. Building server capabilities

    DEFF Research Database (Denmark)

    Adeyemi, Oluseyi

    Many western companies have moved part of their operations to China in order to take advantage of cheap resources and/or to gain access to a high potential market. Depending on motive, offshore facilities usually start either as “sales-only” of products exported by headquarters or “production......-only”, exporting parts and components back to headquarter for sales in the home country. In the course of time, the role of offshore subsidiaries in a company’s operations network tends to change and, with that, the capabilities, of the subsidiaries. Focusing on Danish subsidiaries in China, the objective...

  6. Activity of Renshaw cells during locomotor-like rhythmic activity in the isolated spinal cord of neonatal mice

    DEFF Research Database (Denmark)

    Nishimaru, Hiroshi; Restrepo, Carlos E.; Kiehn, Ole

    2006-01-01

    % of the recorded RCs fired in-phase with the ipsilateral L2 flexor-related rhythm, whereas the rest fired in the extensor phase. Each population of RCs fired throughout the corresponding locomotor phase. All RCs received both excitatory and inhibitory synaptic inputs during the locomotor-like rhythmic activity...

  7. Dynamics

    CERN Document Server

    Goodman, Lawrence E

    2001-01-01

    Beginning text presents complete theoretical treatment of mechanical model systems and deals with technological applications. Topics include introduction to calculus of vectors, particle motion, dynamics of particle systems and plane rigid bodies, technical applications in plane motions, theory of mechanical vibrations, and more. Exercises and answers appear in each chapter.

  8. Laboratory microfusion capability study

    International Nuclear Information System (INIS)

    1993-05-01

    The purpose of this study is to elucidate the issues involved in developing a Laboratory Microfusion Capability (LMC) which is the major objective of the Inertial Confinement Fusion (ICF) program within the purview of the Department of Energy's Defense Programs. The study was initiated to support a number of DOE management needs: to provide insight for the evolution of the ICF program; to afford guidance to the ICF laboratories in planning their research and development programs; to inform Congress and others of the details and implications of the LMC; to identify criteria for selection of a concept for the Laboratory Microfusion Facility and to develop a coordinated plan for the realization of an LMC. As originally proposed, the LMC study was divided into two phases. The first phase identifies the purpose and potential utility of the LMC, the regime of its performance parameters, driver independent design issues and requirements, its development goals and requirements, and associated technical, management, staffing, environmental, and other developmental and operational issues. The second phase addresses driver-dependent issues such as specific design, range of performance capabilities, and cost. The study includes four driver options; the neodymium-glass solid state laser, the krypton fluoride excimer gas laser, the light-ion accelerator, and the heavy-ion induction linear accelerator. The results of the Phase II study are described in the present report

  9. Leveraging marketing capabilities into competitive advantage and export performance.

    OpenAIRE

    Tan, Q.; Sousa, C. M. P.

    2015-01-01

    Purpose – By using the dynamic capabilities (DC) theory and the theory of competitive advantage, the purpose of this paper is to develop a framework to investigate the role of marketing capabilities on the firm’s export performance. Specifically, this framework depicts the consequences of marketing capabilities and focuses on the relationships among marketing capabilities, competitive advantage, and export performance. Design/methodology/approach – The authors conduct a meta-analysis of ...

  10. Competencies, Capabilities and the Neoschumpeterian Tradition

    DEFF Research Database (Denmark)

    Augier, Mie-Sophia; Teece, David J.

    2004-01-01

    In this paper, Mie Augier and David Teece outline the history and development of the ideas underlying an emerging approach within strategic management research: the dynamic capabili-ties framework. The framework was first outlined by Teece and Pisano (1994), and in the pre-sent paper elaborated...... theory of the firm) and Nelson and Winter (an evolutionary theory of economic change). In the dynamic capability framework firms and markets co-evolve. Managers are now allowed to perform distinct strate-gic roles in shaping both firms and their markets, e.g. through asset- selection and orchestra...... into a topic for further discussion. For example, Augier and Teece identify not only the merits but also the limitations of transaction costs eco-nomics. In this way, the authors pave the way for a more dynamic framework while drawing upon organization theory and scholars like Cyert and March (a behavioral...

  11. GABAB Receptor Stimulation Accentuates the Locomotor Effects of Morphine in Mice Bred for Extreme Sensitivity to the Stimulant Effects of Ethanol

    OpenAIRE

    Holstein, Sarah E.; Phillips, Tamara J.

    2006-01-01

    Mice selectively bred for divergent sensitivity to the locomotor stimulant effects of ethanol (FAST and SLOW) also differ in their locomotor response to morphine. The GABAB receptor has been implicated in the mediation of locomotor stimulation to both ethanol and morphine, and a reduction in ethanol-induced stimulation has been found with the GABAB receptor agonist baclofen in FAST mice. We hypothesized that GABAB receptor activation would also attenuate the locomotor stimulant responses to m...

  12. Volumetric changes in the aging rat brain and its impact on cognitive and locomotor functions.

    Science.gov (United States)

    Hamezah, Hamizah Shahirah; Durani, Lina Wati; Ibrahim, Nor Faeizah; Yanagisawa, Daijiro; Kato, Tomoko; Shiino, Akihiko; Tanaka, Sachiko; Damanhuri, Hanafi Ahmad; Ngah, Wan Zurinah Wan; Tooyama, Ikuo

    2017-12-01

    Impairments in cognitive and locomotor functions usually occur with advanced age, as do changes in brain volume. This study was conducted to assess changes in brain volume, cognitive and locomotor functions, and oxidative stress levels in middle- to late-aged rats. Forty-four male Sprague-Dawley rats were divided into four groups: 14, 18, 23, and 27months of age. 1 H magnetic resonance imaging (MRI) was performed using a 7.0-Tesla MR scanner system. The volumes of the lateral ventricles, medial prefrontal cortex (mPFC), hippocampus, striatum, cerebellum, and whole brain were measured. Open field, object recognition, and Morris water maze tests were conducted to assess cognitive and locomotor functions. Blood was taken for measurements of malondialdehyde (MDA), protein carbonyl content, and antioxidant enzyme activity. The lateral ventricle volumes were larger, whereas the mPFC, hippocampus, and striatum volumes were smaller in 27-month-old rats than in 14-month-old rats. In behavioral tasks, the 27-month-old rats showed less exploratory activity and poorer spatial learning and memory than did the 14-month-old rats. Biochemical measurements likewise showed increased MDA and lower glutathione peroxidase (GPx) activity in the 27-month-old rats. In conclusion, age-related increases in oxidative stress, impairment in cognitive and locomotor functions, and changes in brain volume were observed, with the most marked impairments observed in later age. Copyright © 2017. Published by Elsevier Inc.

  13. Human spinal locomotor control is based on flexibly organized burst generators

    OpenAIRE

    Danner, Simon M.; Hofstoetter, Ursula S.; Freundl, Brigitta; Binder, Heinrich; Mayr, Winfried; Rattay, Frank; Minassian, Karen

    2015-01-01

    Understanding the organisation of human spinal locomotor circuitry after severe CNS damage is essential for improving neurorehabilitation strategies. Danner et al. present evidence of flexibly organised burst-generating elements within the functionally isolated human lumbosacral spinal cord that generate rhythmic patterns in response to constant, repetitive epidural stimulation.

  14. MRT of the locomotor system. 4. rev. and enl. ed.; MRT des Bewegungsapparats

    Energy Technology Data Exchange (ETDEWEB)

    Vahlensieck, Martin [Praxisnetz Radiologie und Nuklearmedizin Bonn Bad Godesberg - RheinSieg, Bonn (Germany); Reiser, Maximilian (ed.) [Klinikum Grosshadern, Muenchen (Germany). Inst. fuer Klinische Radiologie

    2015-02-01

    The book on MRT of the locomotor system covers the following topics: relevant NMT imaging techniques, spinal cord, shoulder, elbows, wrist and fingers, hip region, knee, lower leg - ankle - foot, temporomandibular joint, skeletal muscles, bone marrow, bone and soft tissue tumors, osteoporosis, sacroiliac joint, jaw and periodontium.

  15. Gait quality is improved by locomotor training in individuals with SCI regardless of training approach

    NARCIS (Netherlands)

    Nooijen, C.F.J.; ter Hoeve, N.; Field-Fote, E.C.

    2009-01-01

    Background: While various body weight supported locomotor training (BWSLT) approaches are reported in the literature for individuals with spinal cord injury (SCI), none have evaluated outcomes in terms of gait quality. The purpose of this study was to compare changes in measures of gait quality

  16. S-phenylpiracetam, a selective DAT inhibitor, reduces body weight gain without influencing locomotor activity.

    Science.gov (United States)

    Zvejniece, Liga; Svalbe, Baiba; Vavers, Edijs; Makrecka-Kuka, Marina; Makarova, Elina; Liepins, Vilnis; Kalvinsh, Ivars; Liepinsh, Edgars; Dambrova, Maija

    2017-09-01

    S-phenylpiracetam is an optical isomer of phenotropil, which is a clinically used nootropic drug that improves physical condition and cognition. Recently, it was shown that S-phenylpiracetam is a selective dopamine transporter (DAT) inhibitor that does not influence norepinephrine (NE) or serotonin (5-HT) receptors. The aim of the present study was to study the effects of S-phenylpiracetam treatment on body weight gain, blood glucose and leptin levels, and locomotor activity. Western diet (WD)-fed mice and obese Zucker rats were treated daily with peroral administration of S-phenylpiracetam for 8 and 12weeks, respectively. Weight gain and plasma metabolites reflecting glucose metabolism were measured. Locomotor activity was detected in an open-field test. S-phenylpiracetam treatment significantly decreased body weight gain and fat mass increase in the obese Zucker rats and in the WD-fed mice. In addition, S-phenylpiracetam reduced the plasma glucose and leptin concentration and lowered hyperglycemia in a glucose tolerance test in both the mice and the rats. S-phenylpiracetam did not influence locomotor activity in the obese Zucker rats or in the WD-fed mice. The results demonstrate that S-phenylpiracetam reduces body weight gain and improves adaptation to hyperglycemia without stimulating locomotor activity. Our findings suggest that selective DAT inhibitors, such as S-phenylpiracetam, could be potentially useful for treating obesity in patients with metabolic syndrome with fewer adverse health consequences compared to other anorectic agents. Copyright © 2017. Published by Elsevier Inc.

  17. Locomotor performance of cane toads differs between native-range and invasive populations.

    Science.gov (United States)

    Kosmala, Georgia; Christian, Keith; Brown, Gregory; Shine, Richard

    2017-07-01

    Invasive species provide a robust opportunity to evaluate how animals deal with novel environmental challenges. Shifts in locomotor performance-and thus the ability to disperse-(and especially, the degree to which it is constrained by thermal and hydric extremes) are of special importance, because they might affect the rate that an invader can spread. We studied cane toads ( Rhinella marina ) across a broad geographical range: two populations within the species' native range in Brazil, two invasive populations on the island of Hawai'i and eight invasive populations encompassing the eastern, western and southern limits of the toad invasion in Australia. A toad's locomotor performance on a circular raceway was strongly affected by both its temperature and its hydration state, but the nature and magnitude of those constraints differed across populations. In their native range, cane toads exhibited relatively low performance (even under optimal test conditions) and a rapid decrease in performance at lower temperatures and hydration levels. At the other extreme, performance was high in toads from southern Australia, and virtually unaffected by desiccation. Hawai'ian toads broadly resembled their Brazilian conspecifics, plausibly reflecting similar climatic conditions. The invasion of Australia has been accompanied by a dramatic enhancement in the toads' locomotor abilities, and (in some populations) by an ability to maintain locomotor performance even when the animal is cold and/or dehydrated. The geographical divergences in performance among cane toad populations graphically attest to the adaptability of invasive species in the face of novel abiotic challenges.

  18. NeuroRecovery Network provides standardization of locomotor training for persons with incomplete spinal cord injury.

    Science.gov (United States)

    Morrison, Sarah A; Forrest, Gail F; VanHiel, Leslie R; Davé, Michele; D'Urso, Denise

    2012-09-01

    To illustrate the continuity of care afforded by a standardized locomotor training program across a multisite network setting within the Christopher and Dana Reeve Foundation NeuroRecovery Network (NRN). Single patient case study. Two geographically different hospital-based outpatient facilities. This case highlights a 25-year-old man diagnosed with C4 motor incomplete spinal cord injury with American Spinal Injury Association Impairment Scale grade D. Standardized locomotor training program 5 sessions per week for 1.5 hours per session, for a total of 100 treatment sessions, with 40 sessions at 1 center and 60 at another. Ten-meter walk test and 6-minute walk test were assessed at admission and discharge across both facilities. For each of the 100 treatment sessions percent body weight support, average, and maximum treadmill speed were evaluated. Locomotor endurance, as measured by the 6-minute walk test, and overground gait speed showed consistent improvement from admission to discharge. Throughout training, the patient decreased the need for body weight support and was able to tolerate faster treadmill speeds. Data indicate that the patient continued to improve on both treatment parameters and walking function. Standardization across the NRN centers provided a mechanism for delivering consistent and reproducible locomotor training programs across 2 facilities without disrupting training or recovery progression. Copyright © 2012 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.

  19. Initial locomotor sensitivity to cocaine varies widely among inbred mouse strains.

    Science.gov (United States)

    Wiltshire, T; Ervin, R B; Duan, H; Bogue, M A; Zamboni, W C; Cook, S; Chung, W; Zou, F; Tarantino, L M

    2015-03-01

    Initial sensitivity to psychostimulants can predict subsequent use and abuse in humans. Acute locomotor activation in response to psychostimulants is commonly used as an animal model of initial drug sensitivity and has been shown to have a substantial genetic component. Identifying the specific genetic differences that lead to phenotypic differences in initial drug sensitivity can advance our understanding of the processes that lead to addiction. Phenotyping inbred mouse strain panels are frequently used as a first step for studying the genetic architecture of complex traits. We assessed locomotor activation following a single, acute 20 mg/kg dose of cocaine (COC) in males from 45 inbred mouse strains and observed significant phenotypic variation across strains indicating a substantial genetic component. We also measured levels of COC, the active metabolite, norcocaine and the major inactive metabolite, benzoylecgonine, in plasma and brain in the same set of inbred strains. Pharmacokinetic (PK) and behavioral data were significantly correlated, but at a level that indicates that PK alone does not account for the behavioral differences observed across strains. Phenotypic data from this reference population of inbred strains can be utilized in studies aimed at examining the role of psychostimulant-induced locomotor activation on drug reward and reinforcement and to test theories about addiction processes. Moreover, these data serve as a starting point for identifying genes that alter sensitivity to the locomotor stimulatory effects of COC. © 2015 John Wiley & Sons Ltd and International Behavioural and Neural Genetics Society.

  20. Slow Versus Fast Robot-Assisted Locomotor Training After Severe Stroke: A Randomized Controlled Trial.

    Science.gov (United States)

    Rodrigues, Thais Amanda; Goroso, Daniel Gustavo; Westgate, Philip M; Carrico, Cheryl; Batistella, Linamara R; Sawaki, Lumy

    2017-10-01

    Robot-assisted locomotor training on a bodyweight-supported treadmill is a rehabilitation intervention that compels repetitive practice of gait movements. Standard treadmill speed may elicit rhythmic movements generated primarily by spinal circuits. Slower-than-standard treadmill speed may elicit discrete movements, which are more complex than rhythmic movements and involve cortical areas. Compare effects of fast (i.e., rhythmic) versus slow (i.e., discrete) robot-assisted locomotor training on a bodyweight-supported treadmill in subjects with chronic, severe gait deficit after stroke. Subjects (N = 18) were randomized to receive 30 sessions (5 d/wk) of either fast or slow robot-assisted locomotor training on a bodyweight-supported treadmill in an inpatient setting. Functional ambulation category, time up and go, 6-min walk test, 10-m walk test, Berg Balance Scale, and Fugl-Meyer Assessment were administered at baseline and postintervention. The slow group had statistically significant improvement on functional ambulation category (first quartile-third quartile, P = 0.004), 6-min walk test (95% confidence interval [CI] = 1.8 to 49.0, P = 0.040), Berg Balance Scale (95% CI = 7.4 to 14.8, P locomotor training on a bodyweight-supported treadmill after severe stroke, slow training targeting discrete movement may yield greater benefit than fast training.

  1. Functional organization of V2a-related locomotor circuits in the rodent spinal cord

    DEFF Research Database (Denmark)

    Dougherty, Kimberly J.; Kiehn, Ole

    2010-01-01

    Studies of mammalian locomotion have been greatly facilitated by the use of the isolated rodent spinal cord preparation that retains the locomotor circuits needed to execute the movement. Physiological and molecular genetic experiments in this preparation have started to unravel the basic circuit...

  2. Self-Motion Perception during Locomotor Recalibration: More than Meets the Eye

    Science.gov (United States)

    Durgin, Frank H.; Pelah, Adar; Fox, Laura F.; Lewis, Jed; Kane, Rachel; Walley, Katherine A.

    2005-01-01

    Do locomotor after effects depend specifically on visual feedback? In 7 experiments, 116 college students were tested, with closed eyes, at stationary running or at walking to a previewed target after adaptation, with closed eyes, to treadmill locomotion. Subjects showed faster inadvertent drift during stationary running and increased distance…

  3. Temperature and Population Density Effects on Locomotor Activity of Musca domestica (Diptera: Muscidae)

    DEFF Research Database (Denmark)

    Schou, T. M.; Faurby, S.; Kjærsgaard, A.

    2013-01-01

    The behavior of ectotherm organisms is affected by both abiotic and biotic factors. However, a limited number of studies have investigated the synergistic effects on behavioral traits. This study examined the effect of temperature and density on locomotor activity of Musca domestica (L.). Locomot...

  4. The morphological development of the locomotor and cardiac muscles of the migratory barnacle goose (Branta leucopsis)

    NARCIS (Netherlands)

    Bishop, CM; Butler, PJ; ElHaj, AJ; Egginton, S; Loonen, MJJE

    The masses of the locomotor and cardiac muscles of wild barnacle goose goslings, from a migratory population, were examined systematically during development and their values compared to those of pre-migratory geese. Pre-flight development was typified by approximately linear increases of body, leg,

  5. Effects of sex pheromones and sexual maturation on locomotor activity in female sea lamprey (Petromyzon marinus)

    Science.gov (United States)

    Walaszczyk, Erin J.; Johnson, Nicholas S.; Steibel, Juan Pedro; Li, Weiming

    2013-01-01

    Synchronization of male and female locomotor rhythmicity can play a vital role in ensuring reproductive success. Several physiological and environmental factors alter these locomotor rhythms. As sea lamprey, Petromyzon marinus, progress through their life cycle, their locomotor activity rhythm changes multiple times. The goal of this study was to elucidate the activity patterns of adult female sea lamprey during the sexual maturation process and discern the interactions of these patterns with exposure to male pheromones. During these stages, preovulated and ovulated adult females are exposed to sex pheromone compounds, which are released by spermiated males and attract ovulated females to the nest for spawning. The locomotor behavior of adult females was monitored in a natural stream with a passive integrated tag responder system as they matured, and they were exposed to a sex pheromone treatment (spermiated male washings) or a control (prespermiated male washings). Results showed that, dependent on the hour of day, male sex pheromone compounds reduce total activity (p reproductive synchrony of mature adults, thus increasing reproductive success in this species.

  6. Drugs that Target Dopamine Receptors: Changes in Locomotor Activity in Larval Zebrafish

    Science.gov (United States)

    As part of an effort at the US Environmental Protection Agency to develop a rapid in vivo screen for prioritization of toxic chemicals, we have begun to characterize the locomotor activity of zebrafish (Danio rerio) larvae. This includes assessing the acute effects of drugs known...

  7. Efficacy of Static Magnetic Field for Locomotor Activity of Experimental Osteopenia

    Directory of Open Access Journals (Sweden)

    Norimasa Taniguchi

    2007-01-01

    Full Text Available In order to examine the effectiveness of applying a static magnetic field (SMF for increasing bone mineral density (BMD, we assessed the degree of osteopenia by dual-energy X-ray absorptiometry (DEXA, the metabolism measuring system, and histological examination of bone tissue in an ovariectomized (OVX rat model. Thirty-six female Wistar rats (8 weeks old, 160–180 g were divided into three groups. The rats in the OVX-M group were exposed to SMF for 12 weeks after ovariectomy. The ovariectomized rats in the OVX-D group were not exposed to SMF as a control. The rats in the normal group received neither ovariectomy nor exposure to SMF. Twelve-week exposure to SMF in the OVX-M group inhibited the reduction in BMD that was observed in the OVX-D group. Moreover, in the OVX rats, before exposure to SMF, there was no clear difference in the level of locomotor activity between the active and resting phases, and the pattern of locomotor activity was irregular. After exposure of OVX rats to SMF, the pattern of locomotor activity became diphasic with clear active and resting phases, as was observed in the normal group. In the OVX-M group, the continuity of the trabecular bone was maintained more favorably and bone mass was higher than the respective parameters in the OVX-D group. These results demonstrate that exposure to SMF increased the level of locomotor activity in OVX rats, thereby increasing BMD.

  8. Plateau properties in mammalian spinal interneurons during transmitter-induced locomotor activity

    DEFF Research Database (Denmark)

    Kiehn, O.; Johnson, B. R.; Raastad, M.

    1996-01-01

    We examined the organization of spinal networks controlling locomotion in the isolated spinal cord of the neonatal rat, and in this study we provide the first demonstration of plateau and bursting mechanisms in mammalian interneurons that show locomotor-related activity. Using tight-seal whole...

  9. Engagement of the Rat Hindlimb Motor Cortex across Natural Locomotor Behaviors

    NARCIS (Netherlands)

    DiGiovanna, J.; Dominici, N.; Friedli, L.; Rigosa, J.; Duis, S.; Kreider, J.; Beauparlant, J.; van den Brand, R.; Schieppati, M.; Micera, S.; Courtine, G.

    2016-01-01

    Contrary to cats and primates, cortical contribution to hindlimb locomotor movements is not critical in rats. However, the importance of the motor cortex to regain locomotion after neurological disorders in rats suggests that cortical engagement in hindlimb motor control may depend on the behavioral

  10. Efficacy of Stochastic Vestibular Stimulation to Improve Locomotor Performance During Adaptation to Visuomotor and Somatosensory Distortion.

    Science.gov (United States)

    Temple, David R; De Dios, Yiri E; Layne, Charles S; Bloomberg, Jacob J; Mulavara, Ajitkumar P

    2018-01-01

    Astronauts exposed to microgravity face sensorimotor challenges affecting balance control when readapting to Earth's gravity upon return from spaceflight. Small amounts of electrical noise applied to the vestibular system have been shown to improve balance control during standing and walking under discordant sensory conditions in healthy subjects, likely by enhancing information transfer through the phenomenon of stochastic resonance. The purpose of this study was to test the hypothesis that imperceptible levels of stochastic vestibular stimulation (SVS) could improve short-term adaptation to a locomotor task in a novel sensory discordant environment. Healthy subjects (14 males, 10 females, age = 28.7 ± 5.3 years, height = 167.2 ± 9.6 cm, weight = 71.0 ± 12.8 kg) were tested for perceptual thresholds to sinusoidal currents applied across the mastoids. Subjects were then randomly and blindly assigned to an SVS group receiving a 0-30 Hz Gaussian white noise electrical stimulus at 50% of their perceptual threshold (stim) or a control group receiving zero stimulation during Functional Mobility Tests (FMTs), nine trials of which were done under conditions of visual discordance (wearing up/down vision reversing goggles). Time to complete the course (TCC) was used to test the effect of SVS between the two groups across the trials. Adaptation rates from the normalized TCCs were also compared utilizing exponent values of power fit trendline equations. A one-tailed independent-samples t -test indicated these adaptation rates were significantly faster in the stim group ( n = 12) than the control ( n = 12) group [ t (16.18) = 2.00, p = 0.031]. When a secondary analysis was performed comparing "responders" (subjects who showed faster adaptation rates) of the stim ( n = 7) group to the control group ( n = 12), independent-samples t -tests revealed significantly faster trial times for the last five trials with goggles in the stim group "responders" than the controls. The data

  11. A single exercise bout and locomotor learning after stroke: physiological, behavioural, and computational outcomes.

    Science.gov (United States)

    Charalambous, Charalambos C; Alcantara, Carolina C; French, Margaret A; Li, Xin; Matt, Kathleen S; Kim, Hyosub E; Morton, Susanne M; Reisman, Darcy S

    2018-05-15

    Previous work demonstrated an effect of a single high-intensity exercise bout coupled with motor practice on the retention of a newly acquired skilled arm movement, in both neurologically intact and impaired adults. In the present study, using behavioural and computational analyses we demonstrated that a single exercise bout, regardless of its intensity and timing, did not increase the retention of a novel locomotor task after stroke. Considering both present and previous work, we postulate that the benefits of exercise effect may depend on the type of motor learning (e.g. skill learning, sensorimotor adaptation) and/or task (e.g. arm accuracy-tracking task, walking). Acute high-intensity exercise coupled with motor practice improves the retention of motor learning in neurologically intact adults. However, whether exercise could improve the retention of locomotor learning after stroke is still unknown. Here, we investigated the effect of exercise intensity and timing on the retention of a novel locomotor learning task (i.e. split-belt treadmill walking) after stroke. Thirty-seven people post stroke participated in two sessions, 24 h apart, and were allocated to active control (CON), treadmill walking (TMW), or total body exercise on a cycle ergometer (TBE). In session 1, all groups exercised for a short bout (∼5 min) at low (CON) or high (TMW and TBE) intensity and before (CON and TMW) or after (TBE) the locomotor learning task. In both sessions, the locomotor learning task was to walk on a split-belt treadmill in a 2:1 speed ratio (100% and 50% fast-comfortable walking speed) for 15 min. To test the effect of exercise on 24 h retention, we applied behavioural and computational analyses. Behavioural data showed that neither high-intensity group showed greater 24 h retention compared to CON, and computational data showed that 24 h retention was attributable to a slow learning process for sensorimotor adaptation. Our findings demonstrated that acute exercise

  12. Effects of respiratory muscle work on respiratory and locomotor blood flow during exercise.

    Science.gov (United States)

    Dominelli, Paolo B; Archiza, Bruno; Ramsook, Andrew H; Mitchell, Reid A; Peters, Carli M; Molgat-Seon, Yannick; Henderson, William R; Koehle, Michael S; Boushel, Robert; Sheel, A William

    2017-11-01

    What is the central question of this study? Does manipulation of the work of breathing during high-intensity exercise alter respiratory and locomotor muscle blood flow? What is the main finding and its importance? We found that when the work of breathing was reduced during exercise, respiratory muscle blood flow decreased, while locomotor muscle blood flow increased. Conversely, when the work of breathing was increased, respiratory muscle blood flow increased, while locomotor muscle blood flow decreased. Our findings support the theory of a competitive relationship between locomotor and respiratory muscles during intense exercise. Manipulation of the work of breathing (WOB) during near-maximal exercise influences leg blood flow, but the effects on respiratory muscle blood flow are equivocal. We sought to assess leg and respiratory muscle blood flow simultaneously during intense exercise while manipulating WOB. Our hypotheses were as follows: (i) increasing the WOB would increase respiratory muscle blood flow and decrease leg blood flow; and (ii) decreasing the WOB would decrease respiratory muscle blood flow and increase leg blood flow. Eight healthy subjects (n = 5 men, n = 3 women) performed a maximal cycle test (day 1) and a series of constant-load exercise trials at 90% of peak work rate (day 2). On day 2, WOB was assessed with oesophageal balloon catheters and was increased (via resistors), decreased (via proportional assist ventilation) or unchanged (control) during the trials. Blood flow was assessed using near-infrared spectroscopy optodes placed over quadriceps and the sternocleidomastoid muscles, coupled with a venous Indocyanine Green dye injection. Changes in WOB were significantly and positively related to changes in respiratory muscle blood flow (r = 0.73), whereby increasing the WOB increased blood flow. Conversely, changes in WOB were significantly and inversely related to changes in locomotor blood flow (r = 0.57), whereby decreasing the

  13. Oxidized trilinoleate and tridocosahexaenoate induce pica behavior and change locomotor activity.

    Science.gov (United States)

    Kitamura, Fuki; Watanabe, Hiroyuki; Umeno, Aya; Yoshida, Yasukazu; Kurata, Kenji; Gotoh, Naohiro

    2013-01-01

    Pica behavior, a behavior that is characterized by eating a nonfood material such as kaolin and relates to the degree of discomfort in animals, and the variations of locomotor activity of rats after eating deteriorated fat and oil extracted from instant noodles were examined in our previous study. The result shows that oxidized fat and oil with at least 100 meq/kg in peroxide value (PV) increase pica behavior and decrease locomotor activity. In the present study, the same two behaviors were measured using autoxidized trilinoleate (tri-LA) and tridocosahexaenoate (tri-DHA) as a model of vegetable and fish oil, respectively, to compare fatty acid differences against the induction of two behaviors. The oxidized levels of tri-LA and tri-DHA were analyzed with PV and p-anisidine value (AnV), the method to analyze secondary oxidized products. The oxidation levels of respective triacylglycerol (TAG) samples were carefully adjusted to make them having almost the same PV and AnV. As the results, 600 or more meq/kg in PV of both TAGs significantly increased the consumption of kaolin pellets compared to the control group. Furthermore, 300 or more meq/kg in PV of tri-LA and 200 or more meq/kg in PV of tri-DHA demonstrated significant decrease in locomotor activity compared to control group. These results would indicate that the oxidized TAG having the same PV and/or AnV would induce the same type of pica behavior and locomotor activity. Furthermore, that the structure of oxidized products might not be important and the amount of hydroperoxide group and/or aldehyde group in deteriorated fats and oils might affect the pica behavior and locomotor activity were thought.

  14. The effects of long-term dopaminergic treatment on locomotor behavior in rats.

    Science.gov (United States)

    Oliveira de Almeida, Welinton Alessandro; Maculano Esteves, Andrea; Leite de Almeida-Júnior, Canuto; Lee, Kil Sun; Kannebley Frank, Miriam; Oliveira Mariano, Melise; Frussa-Filho, Roberto; Tufik, Sergio; Tulio de Mello, Marco

    2014-12-01

    Long-term treatments with dopaminergic agents are associated with adverse effects, including augmentation. Augmentation consists of an exacerbation of restless legs syndrome (a sleep-related movement disorder) symptoms during treatment compared to those experienced during the period before therapy was initiated. The objective of this study was to examine locomotor activity in rats after long-term dopaminergic treatment and its relationship with expression of the D2 receptor, in addition to demonstrating possible evidence of augmentation. The rats were divided into control (CTRL) and drug (Pramipexole-PPX) groups that received daily saline vehicle and PPX treatments, respectively, for 71 days. The locomotor behavior of the animals was evaluated weekly in the Open Field test for 71 days. The expression of the dopamine D2 receptor was evaluated by Western Blot analysis. The animals that received the PPX demonstrated a significant reduction in locomotor activity from day 1 to day 57 and a significant increase in immobility time from day 1 to day 64 relative to baseline values, but these values had returned to baseline levels at 71 days. No changes in the expression of the D2 receptor were demonstrated after treatment with a dopaminergic agonist. This study suggests changes in locomotor activity in rats after long-term PPX treatment that include an immediate reduction of locomotion and an increase in immobilization, and after 64 days, these values returned to baseline levels without evidence of augmentation. In addition, it was not possible to demonstrate a relationship between locomotor activity and the expression of D2 receptors under these conditions.

  15. The effects of long-term dopaminergic treatment on locomotor behavior in rats

    Science.gov (United States)

    Oliveira de Almeida, Welinton Alessandro; Maculano Esteves, Andrea; Leite de Almeida-Júnior, Canuto; Lee, Kil Sun; Kannebley Frank, Miriam; Oliveira Mariano, Melise; Frussa-Filho, Roberto; Tufik, Sergio; Tulio de Mello, Marco

    2014-01-01

    Long-term treatments with dopaminergic agents are associated with adverse effects, including augmentation. Augmentation consists of an exacerbation of restless legs syndrome (a sleep-related movement disorder) symptoms during treatment compared to those experienced during the period before therapy was initiated. The objective of this study was to examine locomotor activity in rats after long-term dopaminergic treatment and its relationship with expression of the D2 receptor, in addition to demonstrating possible evidence of augmentation. The rats were divided into control (CTRL) and drug (Pramipexole—PPX) groups that received daily saline vehicle and PPX treatments, respectively, for 71 days. The locomotor behavior of the animals was evaluated weekly in the Open Field test for 71 days. The expression of the dopamine D2 receptor was evaluated by Western Blot analysis. The animals that received the PPX demonstrated a significant reduction in locomotor activity from day 1 to day 57 and a significant increase in immobility time from day 1 to day 64 relative to baseline values, but these values had returned to baseline levels at 71 days. No changes in the expression of the D2 receptor were demonstrated after treatment with a dopaminergic agonist. This study suggests changes in locomotor activity in rats after long-term PPX treatment that include an immediate reduction of locomotion and an increase in immobilization, and after 64 days, these values returned to baseline levels without evidence of augmentation. In addition, it was not possible to demonstrate a relationship between locomotor activity and the expression of D2 receptors under these conditions. PMID:26483930

  16. The effects of long-term dopaminergic treatment on locomotor behavior in rats

    Directory of Open Access Journals (Sweden)

    Welinton Alessandro Oliveira de Almeida

    2014-12-01

    Full Text Available Long-term treatments with dopaminergic agents are associated with adverse effects, including augmentation. Augmentation consists of an exacerbation of restless legs syndrome (a sleep-related movement disorder symptoms during treatment compared to those experienced during the period before therapy was initiated. The objective of this study was to examine locomotor activity in rats after long-term dopaminergic treatment and its relationship with expression of the D2 receptor, in addition to demonstrating possible evidence of augmentation. The rats were divided into control (CTRL and drug (Pramipexole—PPX groups that received daily saline vehicle and PPX treatments, respectively, for 71 days. The locomotor behavior of the animals was evaluated weekly in the Open Field test for 71 days. The expression of the dopamine D2 receptor was evaluated by Western Blot analysis. The animals that received the PPX demonstrated a significant reduction in locomotor activity from day 1 to day 57 and a significant increase in immobility time from day 1 to day 64 relative to baseline values, but these values had returned to baseline levels at 71 days. No changes in the expression of the D2 receptor were demonstrated after treatment with a dopaminergic agonist. This study suggests changes in locomotor activity in rats after long-term PPX treatment that include an immediate reduction of locomotion and an increase in immobilization, and after 64 days, these values returned to baseline levels without evidence of augmentation. In addition, it was not possible to demonstrate a relationship between locomotor activity and the expression of D2 receptors under these conditions.

  17. Cocaine-induced locomotor activity in rats selectively bred for low and high voluntary running behavior.

    Science.gov (United States)

    Brown, Jacob D; Green, Caroline L; Arthur, Ian M; Booth, Frank W; Miller, Dennis K

    2015-02-01

    The rewarding effects of physical activity and abused drugs are caused by stimulation of similar brain pathways. Low (LVR) and high (HVR) voluntary running lines were developed by selectively breeding Wistar rats on running distance performance on postnatal days 28-34. We hypothesized that LVR rats would be more sensitive to the locomotor-activating effects of cocaine than HVR rats due to their lower motivation for wheel running. We investigated how selection for LVR or HVR behavior affects inherited activity responses: (a) open field activity levels, (b) habituation to an open field environment, and (c) the locomotor response to cocaine. Open field activity was measured for 80 min on three successive days (days 1-3). Data from the first 20 min were analyzed to determine novelty-induced locomotor activity (day 1) and the habituation to the environment (days 1-3). On day 3, rats were acclimated to the chamber for 20 min and then received saline or cocaine (10, 20, or 30 mg/kg) injection. Dopamine transporter (DAT) protein in the nucleus accumbens was measured via Western blot. Selecting for low and high voluntary running behavior co-selects for differences in inherent (HVR > LVR) and cocaine-induced (LVR > HVR) locomotor activity levels. The differences in the selected behavioral measures do not appear to correlate with DAT protein levels. LVR and HVR rats are an intriguing physical activity model for studying the interactions between genes related to the motivation to run, to use drugs of abuse, and to exhibit locomotor activity.

  18. Flexibility in the patterning and control of axial locomotor networks in lamprey.

    Science.gov (United States)

    Buchanan, James T

    2011-12-01

    In lower vertebrates, locomotor burst generators for axial muscles generally produce unitary bursts that alternate between the two sides of the body. In lamprey, a lower vertebrate, locomotor activity in the axial ventral roots of the isolated spinal cord can exhibit flexibility in the timings of bursts to dorsally-located myotomal muscle fibers versus ventrally-located myotomal muscle fibers. These episodes of decreased synchrony can occur spontaneously, especially in the rostral spinal cord where the propagating body waves of swimming originate. Application of serotonin, an endogenous spinal neurotransmitter known to presynaptically inhibit excitatory synapses in lamprey, can promote decreased synchrony of dorsal-ventral bursting. These observations suggest the possible existence of dorsal and ventral locomotor networks with modifiable coupling strength between them. Intracellular recordings of motoneurons during locomotor activity provide some support for this model. Pairs of motoneurons innervating myotomal muscle fibers of similar ipsilateral dorsoventral location tend to have higher correlations of fast synaptic activity during fictive locomotion than do pairs of motoneurons innervating myotomes of different ipsilateral dorsoventral locations, suggesting their control by different populations of premotor interneurons. Further, these different motoneuron pools receive different patterns of excitatory and inhibitory inputs from individual reticulospinal neurons, conveyed in part by different sets of premotor interneurons. Perhaps, then, the locomotor network of the lamprey is not simply a unitary burst generator on each side of the spinal cord that activates all ipsilateral body muscles simultaneously. Instead, the burst generator on each side may comprise at least two coupled burst generators, one controlling motoneurons innervating dorsal body muscles and one controlling motoneurons innervating ventral body muscles. The coupling strength between these two

  19. Functional reorganization of the locomotor network in Parkinson patients with freezing of gait.

    Directory of Open Access Journals (Sweden)

    Brett W Fling

    Full Text Available Freezing of gait (FoG is a transient inability to initiate or maintain stepping that often accompanies advanced Parkinson's disease (PD and significantly impairs mobility. The current study uses a multimodal neuroimaging approach to assess differences in the functional and structural locomotor neural network in PD patients with and without FoG and relates these findings to measures of FoG severity. Twenty-six PD patients and fifteen age-matched controls underwent resting-state functional magnetic resonance imaging and diffusion tensor imaging along with self-reported and clinical assessments of FoG. After stringent movement correction, fifteen PD patients and fourteen control participants were available for analysis. We assessed functional connectivity strength between the supplementary motor area (SMA and the following locomotor hubs: 1 subthalamic nucleus (STN, 2 mesencephalic and 3 cerebellar locomotor region (MLR and CLR, respectively within each hemisphere. Additionally, we quantified structural connectivity strength between locomotor hubs and assessed relationships with metrics of FoG. FoG+ patients showed greater functional connectivity between the SMA and bilateral MLR and between the SMA and left CLR compared to both FoG- and controls. Importantly, greater functional connectivity between the SMA and MLR was positively correlated with i clinical, ii self-reported and iii objective ratings of freezing severity in FoG+, potentially reflecting a maladaptive neural compensation. The current findings demonstrate a re-organization of functional communication within the locomotor network in FoG+ patients whereby the higher-order motor cortex (SMA responsible for gait initiation communicates with the MLR and CLR to a greater extent than in FoG- patients and controls. The observed pattern of altered connectivity in FoG+ may indicate a failed attempt by the CNS to compensate for the loss of connectivity between the STN and SMA and may reflect a

  20. Aircraft Capability Management

    Science.gov (United States)

    Mumaw, Randy; Feary, Mike

    2018-01-01

    This presentation presents an overview of work performed at NASA Ames Research Center in 2017. The work concerns the analysis of current aircraft system management displays, and the initial development of an interface for providing information about aircraft system status. The new interface proposes a shift away from current aircraft system alerting interfaces that report the status of physical components, and towards displaying the implications of degradations on mission capability. The proposed interface describes these component failures in terms of operational consequences of aircraft system degradations. The research activity was an effort to examine the utility of different representations of complex systems and operating environments to support real-time decision making of off-nominal situations. A specific focus was to develop representations that provide better integrated information to allow pilots to more easily reason about the operational consequences of the off-nominal situations. The work is also seen as a pathway to autonomy, as information is integrated and understood in a form that automated responses could be developed for the off-nominal situations in the future.

  1. Production capability and supply

    International Nuclear Information System (INIS)

    Klemenic, J.

    1977-01-01

    The strong market for uranium of recent years is about to usher in a new era in domestic uranium production. The spot market price of uranium has remained relatively stable at a little over $40/lb for more than 18 months. Many of the recent contracts for delivery in the early 1980s are calling for prices in the range of $40 to $65 per lb in year-of-delivery dollars. Low-grade, high-cost projects, such as uranium recovery from mill tailings and the reopening of ''mined-out'' ore bodies, have already been initiated. New underground mines to produce at greater depths, and new surface mines to recover lower grade ores, are being developed or seriously planned. In keeping with this movement to recover uranium from low-grade ore and other high cost materials, the Grand Junction Office has examined, for the first time, the production capability of the domestic industry assuming a $30/lb (or less) ''forward cost'' resource base. As in the past, keep in mind that the market price needed to stimulate full production of a given resource base may be significantly higher than the estimated forward cost of producing that resource. Results of the $30/lb study are presented

  2. LHC Capabilities for Quarkonia

    CERN Document Server

    Petrushanko, Sergey

    2008-01-01

    The measurement of the charmonium and bottomonium resonances in nucleus-nucleus collisions provides crucial information on high-density QCD matter. First, the suppression of quarkonia production is generally agreed to be one of the most direct probes of quark-gluon plasma formation. The observation of anomalous J/$\\psi$ suppression at the CERN-SPS and at RHIC is well established but the clarification of some important remaining questions requires equivalent studies of the $\\Upsilon$ family, only possible at the LHC energies. Second, the production of heavy-quarks proceeds mainly via gluon-gluon fusion processes and, as such, is sensitive to saturation of the gluon density at low-x in the nucleus. Measured departures from the expected vacuum quarkonia cross-sections in Pb+Pb collisions at the LHC will thus provide valuable information not only on the thermodynamical state of the produced partonic medium, but also on the initial-state modifications of the nuclear parton distribution functions. The capabilities ...

  3. Mobile systems capability plan

    International Nuclear Information System (INIS)

    1996-09-01

    This plan was prepared to initiate contracting for and deployment of these mobile system services. 102,000 cubic meters of retrievable, contact-handled TRU waste are stored at many sites around the country. Also, an estimated 38,000 cubic meters of TRU waste will be generated in the course of waste inventory workoff and continuing DOE operations. All the defense TRU waste is destined for disposal in WIPP near Carlsbad NM. To ship TRU waste there, sites must first certify that the waste meets WIPP waste acceptance criteria. The waste must be characterized, and if not acceptable, subjected to additional processing, including repackaging. Most sites plan to use existing fixed facilities or open new ones between FY1997-2006 to perform these functions; small-quantity sites lack this capability. An alternative to fixed facilities is the use of mobile systems mounted in trailers or skids, and transported to sites. Mobile systems will be used for all characterization and certification at small sites; large sites can also use them. The Carlsbad Area Office plans to pursue a strategy of privatization of mobile system services, since this offers a number of advantages. To indicate the possible magnitude of the costs of deploying mobile systems, preliminary estimates of equipment, maintenance, and operating costs over a 10-year period were prepared and options for purchase, lease, and privatization through fixed-price contracts considered

  4. Strength capability while kneeling.

    Science.gov (United States)

    Haslegrave, C M; Tracy, M F; Corlett, E N

    1997-12-01

    Work sometimes has to be carried out kneeling, particularly where jobs are performed in confined spaces as is common for miners, aircraft baggage handlers and maintenance workers. In order to assess the risks in performing forceful tasks under such conditions, data is needed on strength capabilities of kneeling subjects. A study was undertaken to measure isometric strength in single-handed exertions for male subjects and to investigate the effects on this of task layout factors (direction of force exertion, reach distance, height of the workpiece and orientation relative to the subject's sagittal plane). The data has been tabulated to show the degree to which strength may be reduced in different situations and analysis of the task factors showed their influence to be complex with direction of exertion and reach distance having the greatest effect. The results also suggest that exertions are weaker when subjects are kneeling on two knees than when kneeling on one knee, although this needs to be confirmed by direct experimental comparison.

  5. Decrease of GSK3β phosphorylation in the rat nucleus accumbens core enhances cocaine-induced hyper-locomotor activity.

    Science.gov (United States)

    Kim, Wha Y; Jang, Ju K; Lee, Jung W; Jang, Hyunduk; Kim, Jeong-Hoon

    2013-06-01

    Glycogen synthase kinase 3β (GSK3β), which is abundantly present in the brain, is known to contribute to psychomotor stimulant-induced locomotor behaviors. However, most studies have been focused in showing that GSK3β is able to attenuate psychomotor stimulants-induced hyperactivity by increasing its phosphorylation levels in the nucleus accumbens (NAcc). So, here we examined in the opposite direction about the effects of decreased phosphorylation of GSK3β in the NAcc core on both basal and cocaine-induced locomotor activity by a bilateral microinjection into this site of an artificially synthesized peptide, S9 (0.5 or 5.0 μg/μL), which contains sequences around N-terminal serine 9 residue of GSK3β. We found that decreased levels of GSK3β phosphorylation in the NAcc core enhance cocaine-induced hyper-locomotor activity, while leaving basal locomotor activity unchanged. This is the first demonstration, to our knowledge, that the selective decrease of GSK3β phosphorylation levels in the NAcc core may contribute positively to cocaine-induced locomotor activity, while this is not sufficient for the generation of locomotor behavior by itself without cocaine. Taken together, these findings importantly suggest that GSK3β may need other molecular targets which are co-activated (or deactivated) by psychomotor stimulants like cocaine to contribute to generation of locomotor behaviors. © 2013 International Society for Neurochemistry.

  6. The Effects of Sex-Ratio and Density on Locomotor Activity in the House Fly, Musca domestica

    Science.gov (United States)

    Bahrndorff, Simon; Kjærsgaard, Anders; Pertoldi, Cino; Loeschcke, Volker; Schou, Toke M.; Skovgård, Henrik; Hald, Birthe

    2012-01-01

    Although locomotor activity is involved in almost all behavioral traits, there is a lack of knowledge on what factors affect it. This study examined the effects of sex—ratio and density on the circadian rhythm of locomotor activity of adult Musca domestica L. (Diptera: Muscidae) using an infra—red light system. Sex—ratio significantly affected locomotor activity, increasing with the percentage of males in the vials. In accordance with other studies, males were more active than females, but the circadian rhythm of the two sexes was not constant over time and changed during the light period. There was also an effect of density on locomotor activity, where males at intermediate densities showed higher activity. Further, the predictability of the locomotor activity, estimated as the degree of autocorrelation of the activity data, increased with the number of males present in the vials both with and without the presence of females. Overall, this study demonstrates that locomotor activity in M. domestica is affected by sex—ratio and density. Furthermore, the predictability of locomotor activity is affected by both sex—ratio, density, and circadian rhythm. These results add to our understanding of the behavioral interactions between houseflies and highlight the importance of these factors when designing behavioral experiments using M. domestica.

  7. Swing Boat: Inducing and Recording Locomotor Activity in a Drosophila melanogaster Model of Alzheimer’s Disease

    Directory of Open Access Journals (Sweden)

    Johannes Berlandi

    2017-08-01

    Full Text Available Recent studies indicate that physical activity can slow down progression of neurodegeneration in humans. To date, automated ways to induce activity have been predominantly described in rodent models. To study the impact of activity on behavior and survival in adult Drosophila melanogaster, we aimed to develop a rotating tube device “swing boat” which is capable of monitoring activity and sleep patterns as well as survival rates of flies. For the purpose of a first application, we tested our device on a transgenic fly model of Alzheimer’s disease (AD. Activity of flies was recorded in a climate chamber using the Drosophila Activity Monitoring (DAM System connected to data acquisition software. Locomotor activity was induced by a rotating tube device “swing boat” by repetitively tilting the tubes for 30 min per day. A non-exercising group of flies was used as control and activity and sleep patterns were obtained. The GAL4-/UAS system was used to drive pan-neuronal expression of human Aβ42 in flies. Immunohistochemical stainings for Aβ42 were performed on paraffin sections of adult fly brains. Daily rotation of the fly tubes evoked a pronounced peak of activity during the 30 min exercise period. Pan-neuronal expression of human Aβ42 in flies caused abnormalities in locomotor activity, reduction of life span and elevated sleep fragmentation in comparison to wild type flies. Furthermore, the formation of amyloid accumulations was observed in the adult fly brain. Gently induced activity over 12 days did not evoke prominent effects in wild type flies but resulted in prolongation of median survival time by 7 days (32.6% in Aβ42-expressing flies. Additionally, restoration of abnormally decreased night time sleep (10% and reduced sleep fragmentation (28% were observed compared to non-exercising Aβ42-expressing flies. On a structural level no prominent effects regarding prevalence of amyloid aggregations and Aβ42 RNA expression were

  8. Advanced Techniques for Assessment of Postural and Locomotor Ataxia, Spatial Orientation, and Gaze Stability

    Science.gov (United States)

    Wall, Conrad., III

    1999-01-01

    In addition to adapting to microgravity, major neurovestibular problems of space flight include postflight difficulties with standing, walking, turning corners, and other activities that require stable upright posture and gaze stability. These difficulties inhibit astronauts' ability to stand or escape from their vehicle during emergencies. The long-ter7n goal of the NSBRI is the development of countermeasures to ameliorate the effects of long duration space flight. These countermeasures must be tested with valid and reliable tools. This project aims to develop quantitative, parametric approaches for assessing gaze stability and spatial orientation during normal gait and when gait is perturbed. Two of this year's most important findings concern head fixation distance and ideal trajectory analysis. During a normal cycle of walking the head moves up and down linearly. A simultaneous angular pitching motion of the head keeps it aligned toward an imaginary point in space at a distance of about one meter in front of a subject and along the line of march. This distance is called the head fixation distance. Head fixation distance provides the fundamental framework necessary for understanding the functional significance of the vestibular reflexes that couple head motion to eye motion. This framework facilitates the intelligent design of counter-measures for the effects of exposure to microgravity upon the vestibular ocular reflexes. Ideal trajectory analysis is a simple candidate countermeasure based upon quantifying body sway during repeated up and down stair stepping. It provides one number that estimates the body sway deviation from an ideal sinusoidal body sway trajectory normalized on the subject's height. This concept has been developed with NSBRI funding in less than one year. These findings are explained in more detail below. Compared to assessments of the vestibuo-ocular reflex, analysis of vestibular effects on locomotor function is relatively less well developed

  9. Sandia Laboratories technical capabilities. Auxiliary capabilities: environmental health information science

    International Nuclear Information System (INIS)

    1975-09-01

    Sandia Laboratories is an engineering laboratory in which research, development, testing, and evaluation capabilities are integrated by program management for the generation of advanced designs. In fulfilling its primary responsibility to ERDA, Sandia Laboratories has acquired extensive research and development capabilities. The purpose of this series of documents is to catalog the many technical capabilities of the Laboratories. After the listing of capabilities, supporting information is provided in the form of highlights, which show applications. This document deals with auxiliary capabilities, in particular, environmental health and information science. (11 figures, 1 table) (RWR)

  10. Sandia Laboratories technical capabilities: testing

    International Nuclear Information System (INIS)

    Lundergan, C.D.

    1975-12-01

    The testing capabilities at Sandia Laboratories are characterized. Selected applications of these capabilities are presented to illustrate the extent to which they can be applied in research and development programs

  11. Sandia Laboratories technical capabilities: electronics

    International Nuclear Information System (INIS)

    Lundergan, C.D.

    1975-12-01

    This report characterizes the electronics capabilities at Sandia Laboratories. Selected applications of these capabilities are presented to illustrate the extent to which they can be applied in research and development programs

  12. Cosmopolitan capabilities in the HE classroom

    Directory of Open Access Journals (Sweden)

    Veronica Crosbie

    2014-04-01

    Full Text Available This study, concerning the development of cosmopolitan citizenship, draws on theories of human development and capabilities (Sen 1999; Nussbaum 2000 from a social justice perspective, where individual wellbeing is articulated as having the freedom to live a life of one’s choosing. In the context of an English to Speakers of Other Languages (ESOL classroom this involves paying attention to pedagogical strategies, power dynamics and curriculum content as a means of developing valued beings and doings (or capabilities and functionings as they are described in the literature. Sample activities are presented and evaluated to see to what extent they achieve the desired end. These include critical pedagogical interventions, students’ artefacts and extracts from focus group interviews, class reports and reflective journals.  Results from the textual data offer research evidence of successful curriculum change, demonstrating that the learning that takes place there can make a difference: in terms of the learners’ identity development, capability enhancement and cosmopolitan citizenship.

  13. Stakeholder Alignment and Changing Geospatial Information Capabilities

    Science.gov (United States)

    Winter, S.; Cutcher-Gershenfeld, J.; King, J. L.

    2015-12-01

    Changing geospatial information capabilities can have major economic and social effects on activities such as drought monitoring, weather forecasts, agricultural productivity projections, water and air quality assessments, the effects of forestry practices and so on. Whose interests are served by such changes? Two common mistakes are assuming stability in the community of stakeholders and consistency in stakeholder behavior. Stakeholder communities can reconfigure dramatically as some leave the discussion, others enter, and circumstances shift — all resulting in dynamic points of alignment and misalignment . New stakeholders can bring new interests, and existing stakeholders can change their positions. Stakeholders and their interests need to be be considered as geospatial information capabilities change, but this is easier said than done. New ways of thinking about stakeholder alignment in light of changes in capability are presented.

  14. Structural Capability of an Organization toward Innovation Capability

    DEFF Research Database (Denmark)

    Nielsen, Susanne Balslev; Momeni, Mostafa

    2016-01-01

    The scholars in the field of strategic management have developed two major approaches for attainment of competitive advantage: an approach based on environmental opportunities, and another one based on internal capabilities of an organization. Some investigations in the last two decades have...... indicated that the advantages relying on the internal capabilities of organizations may determine the competitive position of organizations better than environmental opportunities do. Characteristics of firms shows that one of the most internal capabilities that lead the organizations to the strongest...... competitive advantage in the organizations is the innovation capability. The innovation capability is associated with other organizational capabilities, and many organizations have focused on the need to identify innovation capabilities.This research focuses on recognition of the structural aspect...

  15. The Capability to Hold Property

    NARCIS (Netherlands)

    Claassen, Rutger

    2015-01-01

    This paper discusses the question of whether a capability theory of justice (such as that of Martha Nussbaum) should accept a basic “capability to hold property.” Answering this question is vital for bridging the gap between abstract capability theories of justice and their institutional

  16. Movement augmentation to evaluate human control of locomotor stability.

    Science.gov (United States)

    Brown, Geoffrey; Wu, Mengnan Mary; Huang, Felix C; Gordon, Keith E

    2017-07-01

    Controlling center of mass (COM) position and velocity within a dynamic base of support is essential for gait stability. This skill is often compromised following neurologic injury, creating a need to develop effective interventions to enhance gait stability. A movement augmentation paradigm applied to walking could potentially be used to improve control of COM dynamics. We have developed a cable robot system, the Agility Trainer, to apply continuous frontal-plane forces to the pelvis during treadmill walking. This cable robot system uses a set of series elastic actuators powered by linear motors to create bilateral forces. Here we use the Agility Trainer to create a negative viscosity force field proportional to the subject's lateral velocity. Two healthy young subjects performed two 10-minute walking trials, Baseline and Negative Viscosity. During the first minute of walking in the Negative Viscosity field, participants' lateral COM motion became less controlled when compared to the rhythmic sinusoidal motion observed during Baseline walking. By the 10th minute of walking in the Negative Viscosity field the participants had adapted their gait patterns, decreasing their variation in peak lateral COM speed each stride. These results demonstrate that it is feasible to use the Agility Trainer to apply a movement augmentation paradigm to human walking.

  17. Capability-based computer systems

    CERN Document Server

    Levy, Henry M

    2014-01-01

    Capability-Based Computer Systems focuses on computer programs and their capabilities. The text first elaborates capability- and object-based system concepts, including capability-based systems, object-based approach, and summary. The book then describes early descriptor architectures and explains the Burroughs B5000, Rice University Computer, and Basic Language Machine. The text also focuses on early capability architectures. Dennis and Van Horn's Supervisor; CAL-TSS System; MIT PDP-1 Timesharing System; and Chicago Magic Number Machine are discussed. The book then describes Plessey System 25

  18. Locomotor training with body weight support in SCI : EMG improvement is more optimally expressed at a low testing speed

    NARCIS (Netherlands)

    Meyns, P.; Van de Crommert, H. W. A. A.; Rijken, H.; van Kuppevelt, D. H. J. M.; Duysens, J.

    2014-01-01

    Study design: Case series. Objectives: To determine the optimal testing speed at which the recovery of the EMG (electromyographic) activity should be assessed during and after body weight supported (BWS) locomotor training. Setting: Tertiary hospital, Sint Maartenskliniek, Nijmegen, The Netherlands.

  19. The thermal dependency of locomotor performance evolves rapidly within an invasive species.

    Science.gov (United States)

    Kosmala, Georgia K; Brown, Gregory P; Christian, Keith A; Hudson, Cameron M; Shine, Richard

    2018-05-01

    Biological invasions can stimulate rapid shifts in organismal performance, via both plasticity and adaptation. We can distinguish between these two proximate mechanisms by rearing offspring from populations under identical conditions and measuring their locomotor abilities in standardized trials. We collected adult cane toads ( Rhinella marina ) from invasive populations that inhabit regions of Australia with different climatic conditions. We bred those toads and raised their offspring under common-garden conditions before testing their locomotor performance. At high (but not low) temperatures, offspring of individuals from a hotter location (northwestern Australia) outperformed offspring of conspecifics from a cooler location (northeastern Australia). This disparity indicates that, within less than 100 years, thermal performance in cane toads has adapted to the novel abiotic challenges that cane toads have encountered during their invasion of tropical Australia.

  20. Organization of left-right coordination in the mammalian locomotor network

    DEFF Research Database (Denmark)

    Butt, S. J B; Lebret, James M.; Kiehn, Ole

    2002-01-01

    in the spinal cords of a number of aquatic vertebrates including the Xenopus tadpole and the lamprey. However, their function in left-right coordination of limb movements in mammals is poorly understood. In this review we describe the present understanding of commissural pathways in the functioning of spinal......Neuronal circuits involved in left-right coordination are a fundamental feature of rhythmic locomotor movements. These circuits necessarily include commissural interneurons (CINs) that have axons crossing the midline of the spinal cord. The properties of CINs have been described in some detail....... Spinal CINs play an important role in the generation of locomotor output. Increased knowledge as to their function in producing locomotion is likely to provide valuable insights into the spinal networks required for postural control and walking....

  1. Phenotypic characterization of speed-associated gait changes in mice reveals modular organization of locomotor networks

    DEFF Research Database (Denmark)

    Bellardita, Carmelo; Kiehn, Ole

    2015-01-01

    behavioral outcomes expressed at different speeds of locomotion. Here, we use detailed kinematic analyses to search for signatures of a modular organization of locomotor circuits in intact and genetically modified mice moving at different speeds of locomotion. We show that wild-type mice display three...... distinct gaits: two alternating, walk and trot, and one synchronous, bound. Each gait is expressed in distinct ranges of speed with phenotypic inter-limb and intra-limb coordination. A fourth gait, gallop, closely resembled bound in most of the locomotor parameters but expressed diverse inter......-limb coordination. Genetic ablation of commissural V0V neurons completely removed the expression of one alternating gait, trot, but left intact walk, gallop, and bound. Ablation of commissural V0V and V0D neurons led to a loss of walk, trot, and gallop, leaving bound as the default gait. Our study provides...

  2. Impact of Personnel Capabilities on Organizational Innovation Capability

    DEFF Research Database (Denmark)

    Nielsen, Susanne Balslev; Momeni, Mostafa

    2016-01-01

    in this rapidly changing world. This research focuses on definition of the personnel aspect of innovation capability, and proposes a conceptual model based on the scientific articles of academic literature on organisations innovation capability. This paper includes an expert based validation in three rounds...... of the Delphi method. And for the purpose of a better appreciation of the relationship dominating the factors of the model, it has distributed the questionnaire to Iranian companies in the Food industry. This research proposed a direct relationship between Innovation Capability and the Personnel Capability...

  3. Shared human-chimpanzee pattern of perinatal femoral shaft morphology and its implications for the evolution of hominin locomotor adaptations.

    Directory of Open Access Journals (Sweden)

    Naoki Morimoto

    Full Text Available Acquisition of bipedality is a hallmark of human evolution. How bipedality evolved from great ape-like locomotor behaviors, however, is still highly debated. This is mainly because it is difficult to infer locomotor function, and even more so locomotor kinematics, from fossil hominin long bones. Structure-function relationships are complex, as long bone morphology reflects phyletic history, developmental programs, and loading history during an individual's lifetime. Here we discriminate between these factors by investigating the morphology of long bones in fetal and neonate great apes and humans, before the onset of locomotion.Comparative morphometric analysis of the femoral diaphysis indicates that its morphology reflects phyletic relationships between hominoid taxa to a greater extent than taxon-specific locomotor adaptations. Diaphyseal morphology in humans and chimpanzees exhibits several shared-derived features, despite substantial differences in locomotor adaptations. Orangutan and gorilla morphologies are largely similar, and likely represent the primitive hominoid state.These findings are compatible with two possible evolutionary scenarios. Diaphyseal morphology may reflect retained adaptive traits of ancestral taxa, hence human-chimpanzee shared-derived features may be indicative of the locomotor behavior of our last common ancestor. Alternatively, diaphyseal morphology might reflect evolution by genetic drift (neutral evolution rather than selection, and might thus be more informative about phyletic relationships between taxa than about locomotor adaptations. Both scenarios are consistent with the hypothesis that knuckle-walking in chimpanzees and gorillas resulted from convergent evolution, and that the evolution of human bipedality is unrelated to extant great ape locomotor specializations.

  4. Feedback and feedforward locomotor adaptations to ankle-foot load in people with incomplete spinal cord injury.

    Science.gov (United States)

    Gordon, Keith E; Wu, Ming; Kahn, Jennifer H; Schmit, Brian D

    2010-09-01

    Humans with spinal cord injury (SCI) modulate locomotor output in response to limb load. Understanding the neural control mechanisms responsible for locomotor adaptation could provide a framework for selecting effective interventions. We quantified feedback and feedforward locomotor adaptations to limb load modulations in people with incomplete SCI. While subjects airstepped (stepping performed with kinematic assistance and 100% bodyweight support), a powered-orthosis created a dorisflexor torque during the "stance phase" of select steps producing highly controlled ankle-load perturbations. When given repetitive, stance phase ankle-load, the increase in hip extension work, 0.27 J/kg above baseline (no ankle-load airstepping), was greater than the response to ankle-load applied during a single step, 0.14 J/kg (P = 0.029). This finding suggests that, at the hip, subjects produced both feedforward and feedback locomotor modulations. We estimate that, at the hip, the locomotor response to repetitive ankle-load was modulated almost equally by ongoing feedback and feedforward adaptations. The majority of subjects also showed after-effects in hip kinetic patterns that lasted 3 min in response to repetitive loading, providing additional evidence of feedforward locomotor adaptations. The magnitude of the after-effect was proportional to the response to repetitive ankle-foot load (R(2) = 0.92). In contrast, increases in soleus EMG amplitude were not different during repetitive and single-step ankle-load exposure, suggesting that ankle locomotor modulations were predominately feedback-based. Although subjects made both feedback and feedforward locomotor adaptations to changes in ankle-load, between-subject variations suggest that walking function may be related to the ability to make feedforward adaptations.

  5. Dissociation of corticotropin-releasing factor receptor subtype involvement in sensitivity to locomotor effects of methamphetamine and cocaine.

    Science.gov (United States)

    Giardino, William J; Mark, Gregory P; Stenzel-Poore, Mary P; Ryabinin, Andrey E

    2012-02-01

    Enhanced sensitivity to the euphoric and locomotor-activating effects of psychostimulants may influence an individual's predisposition to drug abuse and addiction. While drug-induced behaviors are mediated by the actions of several neurotransmitter systems, past research revealed that the corticotropin-releasing factor (CRF) system is important in driving the acute locomotor response to psychostimulants. We previously reported that genetic deletion of the CRF type-2 receptor (CRF-R2), but not the CRF type-1 receptor (CRF-R1) dampened the acute locomotor stimulant response to methamphetamine (1 mg/kg). These results contrasted with previous studies implicating CRF-R1 in the locomotor effects of psychostimulants. Since the majority of previous studies focused on cocaine, rather than methamphetamine, we set out to test the hypothesis that these drugs differentially engage CRF-R1 and CRF-R2. We expanded our earlier findings by first replicating our previous experiments at a higher dose of methamphetamine (2 mg/kg), and by assessing the effects of the CRF-R1-selective antagonist CP-376,395 (10 mg/kg) on methamphetamine-induced locomotor activity. Next, we used both genetic and pharmacological tools to examine the specific components of the CRF system underlying the acute locomotor response to cocaine (5-10 mg/kg). While genetic deletion of CRF-R2 dampened the locomotor response to methamphetamine (but not cocaine), genetic deletion and pharmacological blockade of CRF-R1 dampened the locomotor response to cocaine (but not methamphetamine). These findings highlight the differential involvement of CRF receptors in acute sensitivity to two different stimulant drugs of abuse, providing an intriguing basis for the development of more targeted therapeutics for psychostimulant addiction.

  6. Development of sensory system s related with postural - locomotor function in toddler ́s age, possibilities of assessmen

    OpenAIRE

    Blažková, Markéta

    2014-01-01

    Bachelor's thesis "Development of sensory systems related with postural-locomotor function in toddler's age, possibilities of assessment" summarizes function of visual, vestibular and somatosensory system and maturation of these systems in toddler's age. Next part describes the development of postural- locomotor function related to maturation of sensory systems. The last part of the work deals with the issue of assessment in toddler's age. Three toddlers are described in the practical part of...

  7. Increased amphetamine-induced locomotor activity, sensitization, and accumbal dopamine release in M5 muscarinic receptor knockout mice

    DEFF Research Database (Denmark)

    Schmidt, Lene S; Miller, Anthony D; Lester, Deranda B

    2010-01-01

    showed that M(5) receptor knockout (M (5) (-/-) ) mice are less sensitive to the reinforcing properties of addictive drugs. MATERIALS AND METHODS: Here, we investigate the role of M(5) receptors in the effects of amphetamine and cocaine on locomotor activity, locomotor sensitization, and dopamine release......-induced hyperactivity and dopamine release as well as amphetamine sensitization are enhanced in mice lacking the M(5) receptor. These results support the concept that the M(5) receptor modulates effects of addictive drugs....

  8. The number of postsynaptic currents necessary to produce locomotor- related cyclic information in neurons in the neonatal rat spinal cord

    DEFF Research Database (Denmark)

    Raastad, Morten; Johnson, Bruce R.; Kiehn, Ole

    1996-01-01

    To understand better how synaptic signaling contributes to network activity, we analyzed the potential contribution of putative unitary postsynaptic currents (PSCs) to locomotor-related information received by spinal interneurons in neonatal rats. The average cyclic modulation of the whole-cell c......-5) of the synapses contributing to the cyclic information need to be active simultaneously. This suggests that individual presynaptic cells in a central locomotor network can have a powerful influence on other neurons....

  9. Classification of rhythmic locomotor patterns in electromyographic signals using fuzzy sets

    Directory of Open Access Journals (Sweden)

    Thrasher Timothy A

    2011-12-01

    Full Text Available Abstract Background Locomotor control is accomplished by a complex integration of neural mechanisms including a central pattern generator, spinal reflexes and supraspinal control centres. Patterns of muscle activation during walking exhibit an underlying structure in which groups of muscles seem to activate in united bursts. Presented here is a statistical approach for analyzing Surface Electromyography (SEMG data with the goal of classifying rhythmic "burst" patterns that are consistent with a central pattern generator model of locomotor control. Methods A fuzzy model of rhythmic locomotor patterns was optimized and evaluated using SEMG data from a convenience sample of four able-bodied individuals. As well, two subjects with pathological gait participated: one with Parkinson's Disease, and one with incomplete spinal cord injury. Subjects walked overground and on a treadmill while SEMG was recorded from major muscles of the lower extremities. The model was fit to half of the recorded data using non-linear optimization and validated against the other half of the data. The coefficient of determination, R2, was used to interpret the model's goodness of fit. Results Using four fuzzy burst patterns, the model was able to explain approximately 70-83% of the variance in muscle activation during treadmill gait and 74% during overground gait. When five burst functions were used, one function was found to be redundant. The model explained 81-83% of the variance in the Parkinsonian gait, and only 46-59% of the variance in spinal cord injured gait. Conclusions The analytical approach proposed in this article is a novel way to interpret multichannel SEMG signals by reducing the data into basic rhythmic patterns. This can help us better understand the role of rhythmic patterns in locomotor control.

  10. Effects of cocaine on norepinephrine stimulated phosphoinositide hydrolysis and locomotor activity in rat

    International Nuclear Information System (INIS)

    Mosaddeghi, M.

    1989-01-01

    The function of α 1 -adrenoceptors was determined by stimulating cortical tissue slices, which were pre-labeled with [ 3 H]inositol, with norepinephrine (NE) in the presence of 8 mM LiCl. Results of in vitro studies showed that cocaine 10 μM potentiated maximal NE-stimulated PI hydrolysis by 30%. In addition, the EC 50 was decreased from 3.93 ± 0.42 to 1.91 ± 0.31 μM NE. Concentrations of 0.1-100 μM and 0.1-10 μM cocaine enhanced PI hydrolysis stimulated by 0.3 and 3 μM NE, respectively. The concentration-effect curves for NE-stimulated PI hydrolysis were shifted to the right 100-fold in the presence of 0.1 μM prazosin. Cocaine (10 μM) did not potentiate NE-stimulated PI hydrolysis in the presence of 0.1 μM prazosin. [ 3 H]Prazosin saturation and NE [ 3 H]prazosin competition binding studies using crude membrane preparations showed that 10 μM cocaine did not alter binding parameters B max , K d , Hill slope, and IC 50 . Together, these results implied that cocaine in vitro potentiated NE-stimulated PI hydrolysis by blocking NE reuptake. For in vivo studies, the locomotor activity was determined after an acute or chronic injections of either cocaine or saline. Cocaine or saline-treated rats were killed after measurement of the locomotor activity, and NE-stimulated PI hydrolysis was measured. Acute administration of cocaine 3.2-42 mg/kg (i.p.) produced an inverted U shaped dose-response curve on locomotor activity. The peak increase in locomotor activity was at 32 mg/kg cocaine. A dose of 42 mg/kg cocaine produced a significant depression of maximal NE-stimulated PI hydrolysis

  11. Effect of temporal organization of the visuo-locomotor coupling on the predictive steering

    Directory of Open Access Journals (Sweden)

    Yves Philippe Rybarczyk

    2012-07-01

    Full Text Available Studies on the direction of a driver’s gaze while taking a bend show that the individual looks towards the tangent-point of the inside curve. Mathematically, the direction of this point in relation to the car enables the driver to predict the curvature of the road. In the same way, when a person walking in the street makes a turn at the corner, his/her gaze anticipates the rotation of the body. A current explanation for the visuo-motor anticipation over the locomotion would be that the brain, involved in a steering behaviour, executes an internal model of the trajectory that anticipates the path completion, and not the contrary. This paper proposes to test this hypothesis by studying the effect of an artificial manipulation of the visuo-locomotor coupling on the trajectory prediction. In this experiment, subjects remotely control a mobile robot with a pan-tilt camera. This experimental paradigm is chosen to easily and precisely manipulate the temporal organization of the visuo-locomotor coupling. Results show that only the visuo-locomotor coupling organized from the visual sensor to the locomotor organs enables i a significant smoothness of the trajectory and ii a velocity-curvature relationship that follows the 2/3 Power Law. These findings are consistent with the theory of an anticipatory construction of an internal model of the trajectory. This mental representation used by the brain as a forward prediction of the path formation seems conditioned by the motor program. The overall results are discussed in terms of the sensorimotor scheme bases of the predictive coding.

  12. Speed-Dependent Modulation of the Locomotor Behavior in Adult Mice Reveals Attractor and Transitional Gaits.

    Science.gov (United States)

    Lemieux, Maxime; Josset, Nicolas; Roussel, Marie; Couraud, Sébastien; Bretzner, Frédéric

    2016-01-01

    Locomotion results from an interplay between biomechanical constraints of the muscles attached to the skeleton and the neuronal circuits controlling and coordinating muscle activities. Quadrupeds exhibit a wide range of locomotor gaits. Given our advances in the genetic identification of spinal and supraspinal circuits important to locomotion in the mouse, it is now important to get a better understanding of the full repertoire of gaits in the freely walking mouse. To assess this range, young adult C57BL/6J mice were trained to walk and run on a treadmill at different locomotor speeds. Instead of using the classical paradigm defining gaits according to their footfall pattern, we combined the inter-limb coupling and the duty cycle of the stance phase, thus identifying several types of gaits: lateral walk, trot, out-of-phase walk, rotary gallop, transverse gallop, hop, half-bound, and full-bound. Out-of-phase walk, trot, and full-bound were robust and appeared to function as attractor gaits (i.e., a state to which the network flows and stabilizes) at low, intermediate, and high speeds respectively. In contrast, lateral walk, hop, transverse gallop, rotary gallop, and half-bound were more transient and therefore considered transitional gaits (i.e., a labile state of the network from which it flows to the attractor state). Surprisingly, lateral walk was less frequently observed. Using graph analysis, we demonstrated that transitions between gaits were predictable, not random. In summary, the wild-type mouse exhibits a wider repertoire of locomotor gaits than expected. Future locomotor studies should benefit from this paradigm in assessing transgenic mice or wild-type mice with neurotraumatic injury or neurodegenerative disease affecting gait.

  13. A cable-driven locomotor training system for restoration of gait in human SCI.

    Science.gov (United States)

    Wu, Ming; Hornby, T George; Landry, Jill M; Roth, Heidi; Schmit, Brian D

    2011-02-01

    A novel cable-driven robotic locomotor training system was developed to provide compliant assistance/resistance forces to the legs during treadmill training in patients with incomplete spinal cord injury (SCI). Eleven subjects with incomplete SCI were recruited to participate in two experiments to test the feasibility of the robotic gait training system. Specifically, 10 subjects participated in one experimental session to test the characteristics of the robotic gait training system and one subject participated in repeated testing sessions over 8 weeks with the robotic device to test improvements in locomotor function. Limb kinematics were recorded in one experiment to evaluate the system characteristics of the cable-driven locomotor trainer and the overground gait speed and 6 min walking distance were evaluated at pre, 4 and 8 weeks post treadmill training of a single subject as well. The results indicated that the cable driven robotic gait training system improved the kinematic performance of the leg during treadmill walking and had no significant impact on the variability of lower leg trajectory, suggesting a high backdrivability of the cable system. In addition, results from a patient with incomplete SCI indicated that prolonged robotic gait training using the cable robot improved overground gait speed. Results from this study suggested that a cable driven robotic gait training system is effective in improving leg kinematic performance, yet allows variability of gait kinematics. Thus, it seems feasible to improve the locomotor function in human SCI using this cable driven robotic system, warranting testing with a larger group of patients. Copyright © 2010 Elsevier B.V. All rights reserved.

  14. Early-life risperidone enhances locomotor responses to amphetamine during adulthood.

    Science.gov (United States)

    Lee Stubbeman, Bobbie; Brown, Clifford J; Yates, Justin R; Bardgett, Mark E

    2017-10-05

    Antipsychotic drug prescriptions for pediatric populations have increased over the past 20 years, particularly the use of atypical antipsychotic drugs such as risperidone. Most antipsychotic drugs target forebrain dopamine systems, and early-life antipsychotic drug exposure could conceivably reset forebrain neurotransmitter function in a permanent manner that persists into adulthood. This study determined whether chronic risperidone administration during development modified locomotor responses to the dopamine/norepinephrine agonist, D-amphetamine, in adult rats. Thirty-five male Long-Evans rats received an injection of one of four doses of risperidone (vehicle, .3, 1.0, 3.0mg/kg) each day from postnatal day 14 through 42. Locomotor activity was measured for 1h on postnatal days 46 and 47, and then for 24h once a week over the next two weeks. Beginning on postnatal day 75, rats received one of four doses of amphetamine (saline, .3, 1.0, 3.0mg/kg) once a week for four weeks. Locomotor activity was measured for 27h after amphetamine injection. Rats administered risperidone early in life demonstrated increased activity during the 1 and 24h test sessions conducted prior to postnatal day 75. Taking into account baseline group differences, these same rats exhibited significantly more locomotor activity in response to the moderate dose of amphetamine relative to controls. These results suggest that early-life treatment with atypical antipsychotic drugs, like risperidone, permanently alters forebrain catecholamine function and increases sensitivity to drugs that target such function. Copyright © 2017 Elsevier B.V. All rights reserved.

  15. Dentate gyrus neurogenesis ablation via cranial irradiation enhances morphine self-administration and locomotor sensitization.

    Science.gov (United States)

    Bulin, Sarah E; Mendoza, Matthew L; Richardson, Devon R; Song, Kwang H; Solberg, Timothy D; Yun, Sanghee; Eisch, Amelia J

    2018-03-01

    Adult dentate gyrus (DG) neurogenesis is important for hippocampal-dependent learning and memory, but the role of new neurons in addiction-relevant learning and memory is unclear. To test the hypothesis that neurogenesis is involved in the vulnerability to morphine addiction, we ablated adult DG neurogenesis and examined morphine self-administration (MSA) and locomotor sensitization. Male Sprague-Dawley rats underwent hippocampal-focused, image-guided X-ray irradiation (IRR) to eliminate new DG neurons or sham treatment (Sham). Six weeks later, rats underwent either MSA (Sham = 16, IRR = 15) or locomotor sensitization (Sham = 12, IRR = 12). Over 21 days of MSA, IRR rats self-administered ~70 percent more morphine than Sham rats. After 28 days of withdrawal, IRR rats pressed the active lever 40 percent more than Sham during extinction. This was not a general enhancement of learning or locomotion, as IRR and Sham groups had similar operant learning and inactive lever presses. For locomotor sensitization, both IRR and Sham rats sensitized, but IRR rats sensitized faster and to a greater extent. Furthermore, dose-response revealed that IRR rats were more sensitive at a lower dose. Importantly, these increases in locomotor activity were not apparent after acute morphine administration and were not a byproduct of irradiation or post-irradiation recovery time. Therefore, these data, along with other previously published data, indicate that reduced hippocampal neurogenesis confers vulnerability for multiple classes of drugs. Thus, therapeutics to specifically increase or stabilize hippocampal neurogenesis could aid in preventing initial addiction as well as future relapse. © 2017 Society for the Study of Addiction.

  16. Comparative potentialities of X-ray and remote thermographic diagnosis of locomotor system diseases and injuries

    International Nuclear Information System (INIS)

    Rozenfel'd, L.G.; Ternovoj, N.K.; Samokhin, A.V.; Likhosherst, E.K.

    1988-01-01

    The advisability of applying remote infrared tomography to diagnoze locomotor system diseases and injuries is substantiated. 764 patients with different bone and tissue system diseases and injuries are examined. Thermosemiotics in the case of deforming arthrosis of knee and hip joints, inflammatory diseases of joints of various ethiologies, acute chronic osteomyelitis and its exacerbation, is described. The place of remote infrared thermography in the complecx diagnostic examination of a given contingent of patients, is determined. 6 refs.; 4 figs

  17. NO INFLUENCE OF HYPOXIA ON COORDINATION BETWEEN RESPIRATORY AND LOCOMOTOR RHYTHMS DURING ROWING AT MODERATE INTENSITY

    Directory of Open Access Journals (Sweden)

    Nicolas Fabre

    2007-12-01

    Full Text Available Besides neuro-mechanical constraints, chemical or metabolic stimuli have also been proposed to interfere with the coordination between respiratory and locomotor rhythms. In the light of the conflicting data observed in the literature, this study aimed to assess whether acute hypoxia modifies the degree of coordination between respiratory and locomotor rhythms during rowing exercises in order to investigate competitive interactions between neuro-mechanical (movement and chemical (hypoxia respiratory drives. Nine male healthy subjects performed one submaximal 6-min rowing exercise on a rowing ergometer in both normoxia (altitude: 304 m and acute hypoxia (altitude: 2877 m. The exercise intensity was about 40 % and 35 % (for normoxia and hypoxia conditions, respectively of the individual maximal power output measured during an incremental rowing test to volitional exhaustion carried out in normoxia. Metabolic rate and minute ventilation were continuously collected throughout exercise. Locomotor movement and breathing rhythms were continuously recorded and synchronized cycle-by-cycle. The degree of coordination was expressed as a percentage of breaths starting during the same phase of the locomotor cycle. For a same and a constant metabolic rate, acute hypoxia did not influence significantly the degree of coordination (mean ± SEM, normoxia: 20.0 ± 6.2 %, hypoxia: 21.3 ± 11.1 %, p > 0.05 while ventilation and breathing frequency were significantly greater in hypoxia. Our results may suggest that during rowing exercise at a moderate metabolic load, neuro-mechanical locomotion-linked respiratory stimuli appear "stronger" than peripheral chemoreceptors- linked respiratory stimuli induced by hypoxia, in the context of our study

  18. An Intensive Locomotor Training Paradigm Improves Neuropathic Pain following Spinal Cord Compression Injury in Rats.

    Science.gov (United States)

    Dugan, Elizabeth A; Sagen, Jacqueline

    2015-05-01

    Spinal cord injury (SCI) is often associated with both locomotor deficits and sensory dysfunction, including debilitating neuropathic pain. Unfortunately, current conventional pharmacological, physiological, or psychological treatments provide only marginal relief for more than two-thirds of patients, highlighting the need for improved treatment options. Locomotor training is often prescribed as an adjunct therapy for peripheral neuropathic pain but is rarely used to treat central neuropathic pain. The goal of this study was to evaluate the potential anti-nociceptive benefits of intensive locomotor training (ILT) on neuropathic pain consequent to traumatic SCI. Using a rodent SCI model for central neuropathic pain, ILT was initiated either 5 d after injury prior to development of neuropathic pain symptoms (the "prevention" group) or delayed until pain symptoms fully developed (∼3 weeks post-injury, the "reversal" group). The training protocol consisted of 5 d/week of a ramping protocol that started with 11 m/min for 5 min and increased in speed (+1 m/min/week) and time (1-4 minutes/week) to a maximum of two 20-min sessions/d at 15 m/min by the fourth week of training. ILT prevented and reversed the development of heat hyperalgesia and cold allodynia, as well as reversed developed tactile allodynia, suggesting analgesic benefits not seen with moderate levels of locomotor training. Further, the analgesic benefits of ILT persisted for several weeks once training had been stopped. The unique ability of an ILT protocol to produce robust and sustained anti-nociceptive effects, as assessed by three distinct outcome measures for below-level SCI neuropathic pain, suggests that this adjunct therapeutic approach has great promise in a comprehensive treatment strategy for SCI pain.

  19. Behavioral and Locomotor Measurements Using an Open Field Activity Monitoring System for Skeletal Muscle Diseases

    OpenAIRE

    Tatem, Kathleen S.; Quinn, James L.; Phadke, Aditi; Yu, Qing; Gordish-Dressman, Heather; Nagaraju, Kanneboyina

    2014-01-01

    The open field activity monitoring system comprehensively assesses locomotor and behavioral activity levels of mice. It is a useful tool for assessing locomotive impairment in animal models of neuromuscular disease and efficacy of therapeutic drugs that may improve locomotion and/or muscle function. The open field activity measurement provides a different measure than muscle strength, which is commonly assessed by grip strength measurements. It can also show how drugs may affect other body sy...

  20. Distributed plasticity of locomotor pattern generators in spinal cord injured patients.

    Science.gov (United States)

    Grasso, Renato; Ivanenko, Yuri P; Zago, Myrka; Molinari, Marco; Scivoletto, Giorgio; Castellano, Vincenzo; Macellari, Velio; Lacquaniti, Francesco

    2004-05-01

    Recent progress with spinal cord injured (SCI) patients indicates that with training they can recover some locomotor ability. Here we addressed the question of whether locomotor responses developed with training depend on re-activation of the normal motor patterns or whether they depend on learning new motor patterns. To this end we recorded detailed kinematic and EMG data in SCI patients trained to step on a treadmill with body-weight support (BWST), and in healthy subjects. We found that all patients could be trained to step with BWST in the laboratory conditions, but they used new coordinative strategies. Patients with more severe lesions used their arms and body to assist the leg movements via the biomechanical coupling of limb and body segments. In all patients, the phase-relationship of the angular motion of the different lower limb segments was very different from the control, as was the pattern of activity of most recorded muscles. Surprisingly, however, the new motor strategies were quite effective in generating foot motion that closely matched the normal in the laboratory conditions. With training, foot motion recovered the shape, the step-by-step reproducibility, and the two-thirds power relationship between curvature and velocity that characterize normal gait. We mapped the recorded patterns of muscle activity onto the approximate rostrocaudal location of motor neuron pools in the human spinal cord. The reconstructed spatiotemporal maps of motor neuron activity in SCI patients were quite different from those of healthy subjects. At the end of training, the locomotor network reorganized at both supralesional and sublesional levels, from the cervical to the sacral cord segments. We conclude that locomotor responses in SCI patients may not be subserved by changes localized to limited regions of the spinal cord, but may depend on a plastic redistribution of activity across most of the rostrocaudal extent of the spinal cord. Distributed plasticity underlies

  1. The H2O2 scavenger ebselen decreases ethanol-induced locomotor stimulation in mice.

    Science.gov (United States)

    Ledesma, Juan Carlos; Font, Laura; Aragon, Carlos M G

    2012-07-01

    In the brain, the enzyme catalase by reacting with H(2)O(2) forms Compound I (catalase-H(2)O(2) system), which is the main system of central ethanol metabolism to acetaldehyde. Previous research has demonstrated that acetaldehyde derived from central-ethanol metabolism mediates some of the psychopharmacological effects produced by ethanol. Manipulations that modulate central catalase activity or sequester acetaldehyde after ethanol administration modify the stimulant effects induced by ethanol in mice. However, the role of H(2)O(2) in the behavioral effects caused by ethanol has not been clearly addressed. The present study investigated the effects of ebselen, an H(2)O(2) scavenger, on ethanol-induced locomotion. Swiss RjOrl mice were pre-treated with ebselen (0-50mg/kg) intraperitoneally (IP) prior to administration of ethanol (0-3.75g/kg; IP). In another experiment, animals were pre-treated with ebselen (0 or 25mg/kg; IP) before caffeine (15mg/kg; IP), amphetamine (2mg/kg; IP) or cocaine (10mg/kg; IP) administration. Following these treatments, animals were placed in an open field to measure their locomotor activity. Additionally, we evaluated the effect of ebselen on the H(2)O(2)-mediated inactivation of brain catalase activity by 3-amino-1,2,4-triazole (AT). Ebselen selectively prevented ethanol-induced locomotor stimulation without altering the baseline activity or the locomotor stimulating effects caused by caffeine, amphetamine and cocaine. Ebselen reduced the ability of AT to inhibit brain catalase activity. Taken together, these data suggest that a decline in H(2)O(2) levels might result in a reduction of the ethanol locomotor-stimulating effects, indicating a possible role for H(2)O(2) in some of the psychopharmacological effects produced by ethanol. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

  2. Voluntary locomotor activity mitigates oxidative damage associated with isolation stress in the prairie vole (Microtus ochrogaster).

    Science.gov (United States)

    Fletcher, Kelsey L; Whitley, Brittany N; Treidel, Lisa A; Thompson, David; Williams, Annie; Noguera, Jose C; Stevenson, Jennie R; Haussmann, Mark F

    2015-07-01

    Organismal performance directly depends on an individual's ability to cope with a wide array of physiological challenges. For social animals, social isolation is a stressor that has been shown to increase oxidative stress. Another physiological challenge, routine locomotor activity, has been found to decrease oxidative stress levels. Because we currently do not have a good understanding of how diverse physiological systems like stress and locomotion interact to affect oxidative balance, we studied this interaction in the prairie vole (Microtus ochrogaster). Voles were either pair housed or isolated and within the isolation group, voles either had access to a moving wheel or a stationary wheel. We found that chronic periodic isolation caused increased levels of oxidative stress. However, within the vole group that was able to run voluntarily, longer durations of locomotor activity were associated with less oxidative stress. Our work suggests that individuals who demonstrate increased locomotor activity may be better able to cope with the social stressor of isolation. © 2015 The Author(s) Published by the Royal Society. All rights reserved.

  3. Anxiolytics may promote locomotor function recovery in spinal cord injury patients

    Directory of Open Access Journals (Sweden)

    Pierre A Guertin

    2008-09-01

    Full Text Available Pierre A GuertinNeuroscience Unit, Laval University Medical Center (CHUL, Quebec City, CanadaAbstract: Recent findings in animal models of paraplegia suggest that specific nonbenzodiazepine anxiolytics may temporarily restore locomotor functions after spinal cord injury (SCI. Experiments using in vitro models have revealed, indeed, that selective serotonin receptor (5-HTR ligands such as 5-HTR1A agonists, known as relatively safe anxiolytics, can acutely elicit episodes of rhythmic neuronal activity refered to as fictive locomotion in isolated spinal cord preparations. Along the same line, in vivo studies have recently shown that this subclass of anxiolytics can induce, shortly after systemic administration (eg, orally or subcutaneously, some locomotor-like hindlimb movements during 45–60 minutes in completely spinal cord-transected (Tx rodents. Using ‘knock-out’ mice (eg, 5-HTR7-/- and selective antagonists, it has been clearly established that both 5-HTR1A and 5-HTR7 were critically involved in mediating the pro-locomotor effects induced by 8-OH-DPAT (typically referred to as a 5-HTR1A agonist in Tx animals. Taken together, these in vitro and in vivo data strongly support the idea that 5-HTR1A agonists may eventually become constitutive elements of a novel first-in-class combinatorial treatment aimed at periodically inducing short episodes of treadmill stepping in SCI patients.Keywords: 5-HT agonists, anxiolytics, locomotion, SCI

  4. Motor hypertonia and lack of locomotor coordination in mutant mice lacking DSCAM.

    Science.gov (United States)

    Lemieux, Maxime; Laflamme, Olivier D; Thiry, Louise; Boulanger-Piette, Antoine; Frenette, Jérôme; Bretzner, Frédéric

    2016-03-01

    Down syndrome cell adherence molecule (DSCAM) contributes to the normal establishment and maintenance of neural circuits. Whereas there is abundant literature regarding the role of DSCAM in the neural patterning of the mammalian retina, less is known about motor circuits. Recently, DSCAM mutation has been shown to impair bilateral motor coordination during respiration, thus causing death at birth. DSCAM mutants that survive through adulthood display a lack of locomotor endurance and coordination in the rotarod test, thus suggesting that the DSCAM mutation impairs motor control. We investigated the motor and locomotor functions of DSCAM(2J) mutant mice through a combination of anatomical, kinematic, force, and electromyographic recordings. With respect to wild-type mice, DSCAM(2J) mice displayed a longer swing phase with a limb hyperflexion at the expense of a shorter stance phase during locomotion. Furthermore, electromyographic activity in the flexor and extensor muscles was increased and coactivated over 20% of the step cycle over a wide range of walking speeds. In contrast to wild-type mice, which used lateral walk and trot at walking speed, DSCAM(2J) mice used preferentially less coordinated gaits, such as out-of-phase walk and pace. The neuromuscular junction and the contractile properties of muscles, as well as their muscle spindles, were normal, and no signs of motor rigidity or spasticity were observed during passive limb movements. Our study demonstrates that the DSCAM mutation induces dystonic hypertonia and a disruption of locomotor gaits. Copyright © 2016 the American Physiological Society.

  5. Improved gait after repetitive locomotor training in children with cerebral palsy.

    Science.gov (United States)

    Smania, Nicola; Bonetti, Paola; Gandolfi, Marialuisa; Cosentino, Alessandro; Waldner, Andreas; Hesse, Stefan; Werner, Cordula; Bisoffi, Giulia; Geroin, Christian; Munari, Daniele

    2011-02-01

    The aim of this study was to evaluate the effectiveness of repetitive locomotor training with an electromechanical gait trainer in children with cerebral palsy. In this randomized controlled trial, 18 ambulatory children with diplegic or tetraplegic cerebral palsy were randomly assigned to an experimental group or a control group. The experimental group received 30 mins of repetitive locomotor training with an applied technology (Gait Trainer GT I) plus 10 mins of passive joint mobilization and stretching exercises. The control group received 40 mins of conventional physiotherapy. Each subject underwent a total of 10 treatment sessions over a 2-wk period. Performance on the 10-m walk test, 6-min walk test, WeeFIM scale, and gait analysis was evaluated by a blinded rater before and after treatment and at 1-mo follow-up. The experimental group showed significant posttreatment improvement on the 10-m walk test, 6-min walk test, hip kinematics, gait speed, and step length, all of which were maintained at the 1-mo follow-up assessment. No significant changes in performance parameters were observed in the control group. Repetitive locomotor training with an electromechanical gait trainer may improve gait velocity, endurance, spatiotemporal, and kinematic gait parameters in patients with cerebral palsy.

  6. Dose and time relationships of the radioprotector WR-2721 on locomotor activity in mice

    International Nuclear Information System (INIS)

    Landauer, M.R.; Davis, H.D.; Dominitz, J.A.; Weiss, J.F.

    1987-01-01

    The effects of the radioprotector S-2-(3-aminopropylamino)ethylphosphorothioic acid (WR-2721) on locomotor activity were evaluated in CD2F1 male mice. Separate groups of animals (N = 10/group) received an IP injection of vehicle, 25, 50, 100, 200, or 400 mg/kg of WR-2721 immediately before testing. Horizontal and vertical activity were measured using a Digiscan automated animal activity monitor. The latency to onset and duration of action of each dose of the radioprotector were recorded. For both behavioral measures, a significant reduction was observed in activity at doses of 200 and 400 mg/kg. A dose of 200 mg/kg had a 12- to 14-min latency to onset and significantly reduced behavioral activity for 3 hr. Mice injected with 400 mg/kg exhibited locomotor deficits within 8-10 min and were affected for up to 9 hr. The ED50 for horizontal and vertical activities at 1 hr postinjection were determined to be 271 and 105 mg/kg, respectively. The results demonstrate that significant reductions in locomotor activity are exhibited at doses of 200 mg/kg or more and that vertical activity was more sensitive to the disruptive effects of WR-2721 than was horizontal activity

  7. Cognitive Performance and Locomotor Adaptation in Persons With Anterior Cruciate Ligament Reconstruction.

    Science.gov (United States)

    Stone, Amanda E; Roper, Jaimie A; Herman, Daniel C; Hass, Chris J

    2018-05-01

    Persons with anterior cruciate ligament reconstruction (ACLR) show deficits in gait and neuromuscular control following rehabilitation. This altered behavior extends to locomotor adaptation and learning, however the contributing factors to this observed behavior have yet to be investigated. The purpose of this study was to assess differences in locomotor adaptation and learning between ACLR and controls, and identify underlying contributors to motor adaptation in these individuals. Twenty ACLR individuals and 20 healthy controls (CON) agreed to participate in this study. Participants performed four cognitive and dexterity tasks (local version of Trail Making Test, reaction time test, electronic pursuit rotor test, and the Purdue pegboard). Three-dimensional kinematics were also collected while participants walked on a split-belt treadmill. ACLR individuals completed the local versions of Trails A and Trails B significantly faster than CON. During split-belt walking, ACLR individuals demonstrated smaller step length asymmetry during EARLY and LATE adaptation, smaller double support asymmetry during MID adaptation, and larger stance time asymmetry during DE-ADAPT compared with CON. ACLR individuals performed better during tasks that required visual attention and task switching and were less perturbed during split-belt walking compared to controls. Persons with ACLR may use different strategies than controls, cognitive or otherwise, to adapt locomotor patterns.

  8. The locomotor activity of soccer players based on playing positions during the 2010 World Cup.

    Science.gov (United States)

    Soroka, Andrzej

    2018-06-01

    The aim of this study was to define the locomotor activity of footballer players during the 2010 World Cup and to assess what differences existed among different playing positions. Research was conducted using research material collected from the Castrol Performance Index, a kinematic game analysis system that records player movements during a game by use of semi-automatic cameras. A total of 599 players who participated in the championships were analyzed. The results were evaluated using one-way analysis of variance (ANOVA) and a post-hoc test that calculated the Honestly Significant Difference (HSD) in order to determine which mean values significantly differed among the player positions. It was found that midfielders covered on average the largest distance during a match (10,777.6 m, Plocomotor activity at high and sprint intensities (2936.8 m and 108.4 m, respectively). Additionally, midfielders also spent the largest amount of time at performing at a high intensity (10.6%). Strikers also featured high levels of the above parameters; the total length of distance covered with high intensities was found to be on average 2586.7 m, the distance covered at sprint intensity was 105 m. The footballers, playing at the championship level feature excellent locomotor preparation. This fact is undoubtedly supported by the aerobic training of high intensity. Such training allows footballers to extend the distance they cover during the match, increase the intensity of locomotor activities and sprint speed distance.

  9. Effects of opioid drugs on dopamine mediated locomotor activity in rats

    Energy Technology Data Exchange (ETDEWEB)

    Leathern, L L

    1986-01-01

    Opioid drugs influence various behavioural parameters including locomotor activity in experimental animals. The interaction between the opioid and dopaminergic systems is one possible explanation for the effect of opioid drugs on locomotor activity. In this study behavioural and biochemical assays were done to investigate the interaction between the opioid and dopaminergic systems. Behavioural studies were done by measurement of locomotor activity (LA) of rats after acute or chronic pretreatment with opioid andor dopaminergic drugs. Biochemical studies were in the form of radioligand binding assays, the effect on the number (Bmax) and affinity (K/sub D/) of receptors was measured after chronic pretreatment with opioid andor dopaminergic drugs. The opioid drugs used are morphine, nalbuphine and naloxone. Dopaminergic drugs used included: agonists-apomorphine and piribedil; antagonists-pimozide, haloperidol, chlorpromazine. In the acute situation increased LA was obtained with morphine and the DA agonists. A correlation between the behavioural and biochemical assays was found. Chronic pretreatment with morphine enhanced apomorphine induced LA, this supersensitivity was also measured as an increased receptor density (Bmax) of D2 receptors in the striatum. Chronic morphine pretreatment caused a decrease in morphine induced LA, while this subsensitivity was not apparent in the ligand binding assays - where no change in receptor number was observed. Chronic naloxone pretreatment enhanced morphine induced LA, as well as increased the Bmax of opioid receptors in the whole brain. It is concluded that an interaction between the opioid and dopaminergic systems does exist, and may account for the mechanism of action of the opioids.

  10. The influence of an innovative locomotor strategy on the phenotypic diversification of triggerfish (family: Balistidae).

    Science.gov (United States)

    Dornburg, Alex; Sidlauskas, Brian; Santini, Francesco; Sorenson, Laurie; Near, Thomas J; Alfaro, Michael E

    2011-07-01

    Innovations in locomotor morphology have been invoked as important drivers of vertebrate diversification, although the influence of novel locomotion strategies on marine fish diversification remains largely unexplored. Using triggerfish as a case study, we determine whether the evolution of the distinctive synchronization of enlarged dorsal and anal fins that triggerfish use to swim may have catalyzed the ecological diversification of the group. By adopting a comparative phylogenetic approach to quantify median fin and body shape integration and to assess the tempo of functional and morphological evolution in locomotor traits, we find that: (1) functional and morphological components of the locomotive system exhibit a strong signal of correlated evolution; (2) triggerfish partitioned locomotor morphological and functional spaces early in their history; and (3) there is no strong evidence that a pulse of lineage diversification accompanied the major episode of phenotypic diversification. Together these findings suggest that the acquisition of a distinctive mode of locomotion drove an early radiation of shape and function in triggerfish, but not an early radiation of species. © 2011 The Author(s). Evolution© 2011 The Society for the Study of Evolution.

  11. Effects of lipopolysaccharide and interleukin-6 on cataleptic immobility and locomotor activity in mice.

    Science.gov (United States)

    Bazovkina, Daria V; Tibeikina, Marina A; Kulikov, Alexander V; Popova, Nina K

    2011-01-10

    Catalepsy (animal hypnosis, tonic immobility) is a type of passive defensive behavior. Its exaggerated form is a syndrome of some psychopathological disorders. Numerous neurotransmitters have impact on the regulation of catalepsy. In this paper we demonstrated the involvement of interleukin-6 (IL-6) in the mechanism of cataleptic immobility. Effects of exogenous IL-6 treatment (7.5 and 10μg/kg, i.p) or stimulation of endogenous IL-6 secretion with lipopolysaccharide (LPS) administration (50, 100 and 200μg/kg, i.p.) on catalepsy and locomotor activity were studied in adult C57BL/6 male mice. IL-6 induced catalepsy in 70% (7.5μg/kg) or 72.7% (10μg/kg) of animals with no effect on locomotor activity. LPS administration reduced distance travelled and number of rears in the open field at any dose used, however, only high doses (100 or 200μg/kg) of the toxin induced catalepsy in 50% of mice. This result indicates that IL-6 is involved in the regulation of catalepsy, this effect is specific and does not arise from inhibition of locomotor activity. The study provides a new evidence on participation of IL-6 in mechanisms of abnormal behavior. Copyright © 2010 Elsevier Ireland Ltd. All rights reserved.

  12. A disparity between locomotor economy and territory-holding ability in male house mice.

    Science.gov (United States)

    Morris, Jeremy S; Ruff, James S; Potts, Wayne K; Carrier, David R

    2017-07-15

    Both economical locomotion and physical fighting are important performance traits to many species because of their direct influence on components of Darwinian fitness. Locomotion represents a substantial portion of the total daily energy budget of many animals. Fighting performance often determines individual reproductive fitness through the means of resource control, social dominance and access to mates. However, phenotypic traits that improve either locomotor economy or fighting ability may diminish performance in the other. Here, we tested for a predicted disparity between locomotor economy and competitive ability in wild-derived house mice ( Mus musculus ). We used 8 week social competition trials in semi-natural enclosures to directly measure male competitive ability through territorial control and female occupancy within territories. We also measured oxygen consumption during locomotion for each mouse using running trials in an enclosed treadmill and open-flow respirometry. Our results show that territory-holding males have higher absolute and mass-specific oxygen consumption when running (i.e. reduced locomotor economy) compared with males that do not control territories. This relationship was present both before and after 8 week competition trials in semi-natural enclosures. This disparity between physical competitive ability and economical locomotion may impose viability costs on males in species for which competition over mates is common and may constrain the evolution of behavioral and phenotypic diversity, particularly in natural settings with environmental and resource variability. © 2017. Published by The Company of Biologists Ltd.

  13. Catalase inhibition in the Arcuate nucleus blocks ethanol effects on the locomotor activity of rats.

    Science.gov (United States)

    Sanchis-Segura, Carles; Correa, Mercé; Miquel, Marta; Aragon, Carlos M G

    2005-03-07

    Previous studies have demonstrated that there is a bidirectional modulation of ethanol-induced locomotion produced by drugs that regulate brain catalase activity. In the present study we have assessed the effect in rats of intraperitoneal, intraventricular or intracraneal administration of the catalase inhibitor sodium azide in the locomotor changes observed after ethanol (1 g/kg) administration. Our results show that sodium azide prevents the effects of ethanol in rats locomotion not only when sodium azide was systemically administered but also when it was intraventricularly injected, then confirming that the interaction between catalase and ethanol takes place in Central Nervous System (CNS). Even more interestingly, the same results were observed when sodium azide administration was restricted to the hypothalamic Arcuate nucleus (ARC), a brain region which has one of the highest levels of expression of catalase. Therefore, the results of the present study not only confirm a role for brain catalase in the mediation of ethanol-induced locomotor changes in rodents but also point to the ARC as a major neuroanatomical location for this interaction. These results are in agreement with our reports showing that ethanol-induced locomotor changes are clearly dependent of the ARC integrity and, especially of the POMc-synthesising neurons of this nucleus. According to these data we propose a model in which ethanol oxidation via catalase could produce acetaldehyde into the ARC and to promote a release of beta-endorphins that would activate opioid receptors to produce locomotion and other ethanol-induced neurobehavioural changes.

  14. [Disorders of locomotor system and effectiveness of physiotherapy in coal miners].

    Science.gov (United States)

    Bilski, Bartosz; Bednarek, Agata

    2003-01-01

    The aim of the survey was to analyze the efficacy of physiotherapy applied in coal miners as well as to assess their locomotor system load and the effects of working conditions in mines. The questionnaire survey covered a group of 51 miners, aged 28-76 years (mean, 54 years), undergoing physiotherapeutic procedures in the mine out-patient clinic during the first quarter of 2003. The survey revealed that lumbosacral disorders were the most frequent locomotor system complaints reported by miners, especially those who work in a bending down position. According to the clinical data, spondylosis and allied disorders were the main reasons for pain in this part of the body. Having analyzed the relationship between age and occurrence of back pains, the majority of complaints were found in the 46-55 age group (two complaints per one respondent). The analysis of the association between back pains and duration of employment revealed that the complaints for the locomotor system occurred already after a five-year employment. The survey showed that the application of physiotherapeutic procedures diminished the back pain in the study group by 2.83 on average on the 0-10 scale. It was also found that magnetotherapy proved to be the most effective method in treating the spinal degenerative changes.

  15. Influence of temperature on daily locomotor activity in the crab Uca pugilator.

    Directory of Open Access Journals (Sweden)

    Audrey M Mat

    Full Text Available Animals living in the intertidal zone are exposed to prominent temperature changes. To cope with the energetic demands of environmental thermal challenges, ectotherms rely mainly on behavioral responses, which may change depending on the time of the day and seasonally. Here, we analyze how temperature shapes crabs' behavior at 2 different times of the year and show that a transition from constant cold (13.5°C to constant warm (17.5°C water temperature leads to increased locomotor activity levels throughout the day in fiddler crabs (Uca pugilator collected during the summer. In contrast, the same transition in environmental temperature leads to a decrease in the amplitude of the daily locomotor activity rhythm in crabs collected during the winter. In other words, colder temperatures during the cold season favor a more prominent diurnal behavior. We interpret this winter-summer difference in the response of daily locomotor activity to temperature changes within the framework of the circadian thermoenergetics hypothesis, which predicts that a less favorable energetic balance would promote a more diurnal activity pattern. During the winter, when the energetic balance is likely less favorable, crabs would save energy by being more active during the expected high-temperature phase of the day-light phase-and less during the expected low-temperature phase of the day-dark phase. Our results suggest that endogenous rhythms in intertidal ectotherms generate adaptive behavioral programs to cope with thermoregulatory demands of the intertidal habitat.

  16. Locomotor Anatomy and Behavior of Patas Monkeys (Erythrocebus patas with Comparison to Vervet Monkeys (Cercopithecus aethiops

    Directory of Open Access Journals (Sweden)

    Adrienne L. Zihlman

    2013-01-01

    Full Text Available Patas monkeys (Erythrocebus patas living in African savanna woodlands and grassland habitats have a locomotor system that allows them to run fast, presumably to avoid predators. Long fore- and hindlimbs, long foot bones, short toes, and a digitigrade foot posture were proposed as anatomical correlates with speed. In addition to skeletal proportions, soft tissue and whole body proportions are important components of the locomotor system. To further distinguish patas anatomy from other Old World monkeys, a comparative study based on dissection of skin, muscle, and bone from complete individuals of patas and vervet monkeys (Cercopithecus aethiops was undertaken. Analysis reveals that small adjustments in patas skeletal proportions, relative mass of limbs and tail, and specific muscle groups promote efficient sagittal limb motion. The ability to run fast is based on a locomotor system adapted for long distance walking. The patas’ larger home range and longer daily range than those of vervets give them access to highly dispersed, nutritious foods, water, and sleeping trees. Furthermore, patas monkeys have physiological adaptations that enable them to tolerate and dissipate heat. These features all contribute to the distinct adaptation that is the patas monkeys’ basis for survival in grassland and savanna woodland areas.

  17. Mephedrone interactions with cocaine: prior exposure to the 'bath salt' constituent enhances cocaine-induced locomotor activation in rats.

    Science.gov (United States)

    Gregg, Ryan A; Tallarida, Christopher S; Reitz, Allen B; Rawls, Scott M

    2013-12-01

    Concurrent use of mephedrone (4-methylmethcathinone; MEPH) and established drugs of abuse is now commonplace, but knowledge about interactions between these drugs is sparse. The present study was designed to test the hypothesis that prior MEPH exposure enhances the locomotor-stimulant effects of cocaine and methamphetamine (METH). For cocaine experiments, rats pretreated with saline, cocaine (15 mg/kg), or MEPH (15 mg/kg) for 5 days were injected with cocaine after 10 days of drug absence. For METH experiments, rats pretreated with saline, METH (2 mg/kg), or MEPH (15 mg/kg) were injected with METH after 10 days of drug absence. Cocaine challenge produced greater locomotor activity after pretreatment with cocaine or MEPH than after pretreatment with saline. METH challenge produced greater locomotor activity after METH pretreatment than after saline pretreatment; however, locomotor activity in rats pretreated with MEPH or saline and then challenged with METH was not significantly different. The locomotor response to MEPH (15 mg/kg) was not significantly affected by pretreatment with cocaine (15 mg/kg) or METH (0.5, 2 mg/kg). The present demonstration that cocaine-induced locomotor activation is enhanced by prior MEPH exposure suggests that MEPH cross-sensitizes to cocaine and increases cocaine efficacy. Interestingly, MEPH cross-sensitization was not bidirectional and did not extend to METH, suggesting that the phenomenon is sensitive to specific psychostimulants.

  18. Effect of Environmental Conditions and Toxic Compounds on the Locomotor Activity of Pediculus humanus capitis (Phthiraptera: Pediculidae).

    Science.gov (United States)

    Ortega-Insaurralde, I; Toloza, A C; Gonzalez-Audino, P; Mougabure-Cueto, G A; Alvarez-Costa, A; Roca-Acevedo, G; Picollo, M I

    2015-09-01

    In this work, we evaluated the effect of environmental variables such as temperature, humidity, and light on the locomotor activity of Pediculus humanus capitis. In addition, we used selected conditions of temperature, humidity, and light to study the effects of cypermethrin and N,N-diethyl-3-methylbenzamide (DEET) on the locomotor activity of head lice. Head lice increased their locomotor activity in an arena at 30°C compared with activity at 20°C. When we tested the influence of the humidity level, the locomotor activity of head lice showed no significant differences related to humidity level, both at 30°C and 20°C. Concerning light influence, we observed that the higher the intensity of light, the slower the movement of head lice. We also demonstrated that sublethal doses of toxics may alter locomotor activity in adults of head lice. Sublethal doses of cypermethrin induced hyperactivated responses in adult head lice. Sublethal doses of DEET evocated hypoactivated responses in head lice. The observation of stereotyped behavior in head lice elicited by toxic compounds proved that measuring locomotor activity in an experimental set-up where environmental conditions are controlled would be appropriate to evaluate compounds of biological importance, such as molecules involved in the host-parasite interaction and intraspecific relationships. © The Authors 2015. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  19. People Capability Maturity Model. SM.

    Science.gov (United States)

    1995-09-01

    tailored so it consumes less time and resources than a traditional software process assessment or CMU/SEI-95-MM-02 People Capability Maturity Model...improved reputation or customer loyalty. CMU/SEI-95-MM-02 People Capability Maturity Model ■ L5-17 Coaching Level 5: Optimizing Activity 1...Maturity Model CMU/SEI-95-MM-62 Carnegie-Mellon University Software Engineering Institute DTIC ELECTE OCT 2 7 1995 People Capability Maturity

  20. Mechanisms of Left-Right Coordination in Mammalian Locomotor Pattern Generation Circuits: A Mathematical Modeling View

    Science.gov (United States)

    Talpalar, Adolfo E.; Rybak, Ilya A.

    2015-01-01

    The locomotor gait in limbed animals is defined by the left-right leg coordination and locomotor speed. Coordination between left and right neural activities in the spinal cord controlling left and right legs is provided by commissural interneurons (CINs). Several CIN types have been genetically identified, including the excitatory V3 and excitatory and inhibitory V0 types. Recent studies demonstrated that genetic elimination of all V0 CINs caused switching from a normal left-right alternating activity to a left-right synchronized “hopping” pattern. Furthermore, ablation of only the inhibitory V0 CINs (V0D subtype) resulted in a lack of left-right alternation at low locomotor frequencies and retaining this alternation at high frequencies, whereas selective ablation of the excitatory V0 neurons (V0V subtype) maintained the left–right alternation at low frequencies and switched to a hopping pattern at high frequencies. To analyze these findings, we developed a simplified mathematical model of neural circuits consisting of four pacemaker neurons representing left and right, flexor and extensor rhythm-generating centers interacting via commissural pathways representing V3, V0D, and V0V CINs. The locomotor frequency was controlled by a parameter defining the excitation of neurons and commissural pathways mimicking the effects of N-methyl-D-aspartate on locomotor frequency in isolated rodent spinal cord preparations. The model demonstrated a typical left-right alternating pattern under control conditions, switching to a hopping activity at any frequency after removing both V0 connections, a synchronized pattern at low frequencies with alternation at high frequencies after removing only V0D connections, and an alternating pattern at low frequencies with hopping at high frequencies after removing only V0V connections. We used bifurcation theory and fast-slow decomposition methods to analyze network behavior in the above regimes and transitions between them. The model

  1. Descending propriospinal neurons mediate restoration of locomotor function following spinal cord injury

    Science.gov (United States)

    Benthall, Katelyn N.; Hough, Ryan A.

    2016-01-01

    Following spinal cord injury (SCI) in the lamprey, there is virtually complete recovery of locomotion within a few weeks, but interestingly, axonal regeneration of reticulospinal (RS) neurons is mostly limited to short distances caudal to the injury site. To explain this situation, we hypothesize that descending propriospinal (PS) neurons relay descending drive from RS neurons to indirectly activate spinal central pattern generators (CPGs). In the present study, the contributions of PS neurons to locomotor recovery were tested in the lamprey following SCI. First, long RS neuron projections were interrupted by staggered spinal hemitransections on the right side at 10% body length (BL; normalized from the tip of the oral hood) and on the left side at 30% BL. For acute recovery conditions (≤1 wk) and before axonal regeneration, swimming muscle burst activity was relatively normal, but with some deficits in coordination. Second, lampreys received two spaced complete spinal transections, one at 10% BL and one at 30% BL, to interrupt long-axon RS neuron projections. At short recovery times (3–5 wk), RS and PS neurons will have regenerated their axons for short distances and potentially established a polysynaptic descending command pathway. At these short recovery times, swimming muscle burst activity had only minor coordination deficits. A computer model that incorporated either of the two spinal lesions could mimic many aspects of the experimental data. In conclusion, descending PS neurons are a viable mechanism for indirect activation of spinal locomotor CPGs, although there can be coordination deficits of locomotor activity. NEW & NOTEWORTHY In the lamprey following spinal lesion-mediated interruption of long axonal projections of reticulospinal (RS) neurons, sensory stimulation still elicited relatively normal locomotor muscle burst activity, but with some coordination deficits. Computer models incorporating the spinal lesions could mimic many aspects of the

  2. Conditioned Place Preference to Acetone Inhalation and the Effects on Locomotor Behavior and 18FDG Uptake

    Energy Technology Data Exchange (ETDEWEB)

    Pai, J.C.; Dewey, S.L.; Schiffer, W.; Lee, D.

    2006-01-01

    Acetone is a component in many inhalants that have been widely abused. While other solvents have addictive potential, such as toluene, it is unclear whether acetone alone contains addictive properties. The locomotor, relative glucose metabolism and abusive effects of acetone inhalation were studied in animals using the conditioned place preference (CPP) paradigm and [18F]2-fluorodeoxy-D-glucose (18FDG) imaging. The CPP apparatus contains two distinct conditioning chambers and a middle adaptation chamber, each lined with photocells to monitor locomotor activity. Adolescent Sprague-Dawley rats (n=16; 90-110 g) were paired with acetone in least preferred conditioning chamber, determined on the pretest day. The animals were exposed to a 10,000 ppm dose for an hour, alternating days with air. A CPP test was conducted after the 3rd, 6th and 12th pairing. In these same animals, the relative glucose metabolism effects were determined using positron emission tomography (PET) imaging with 18FDG. Following the 3rd pairing, there was a significant aversion to the acetone paired chamber (190.9 ± 13.7 sec and 241.7 ± 16.9 sec, acetone and air, respectively). After the 6th pairing, there was no significant preference observed with equal time spent in each chamber (222 ± 21 sec and 207 ± 20 sec, acetone and air-paired, respectively). A similar trend was observed after the 12th pairing (213 ± 21 sec and 221 ± 22 sec, acetone and air-paired, respectively). Locomotor analysis indicated a significant decrease (p<0.05) from air pairings to acetone pairings on the first and sixth pairings. The observed locomotor activity was characteristic of central nervous system (CNS) depressants, without showing clear abusive effects in this CPP model. In these studies, acetone vapors were not as reinforcing as other solvents, shown by overall lack of preference for the acetone paired side of the chamber. PET imaging indicated a regionally specific distribution of 18FDG uptake following

  3. Descending propriospinal neurons mediate restoration of locomotor function following spinal cord injury.

    Science.gov (United States)

    Benthall, Katelyn N; Hough, Ryan A; McClellan, Andrew D

    2017-01-01

    Following spinal cord injury (SCI) in the lamprey, there is virtually complete recovery of locomotion within a few weeks, but interestingly, axonal regeneration of reticulospinal (RS) neurons is mostly limited to short distances caudal to the injury site. To explain this situation, we hypothesize that descending propriospinal (PS) neurons relay descending drive from RS neurons to indirectly activate spinal central pattern generators (CPGs). In the present study, the contributions of PS neurons to locomotor recovery were tested in the lamprey following SCI. First, long RS neuron projections were interrupted by staggered spinal hemitransections on the right side at 10% body length (BL; normalized from the tip of the oral hood) and on the left side at 30% BL. For acute recovery conditions (≤1 wk) and before axonal regeneration, swimming muscle burst activity was relatively normal, but with some deficits in coordination. Second, lampreys received two spaced complete spinal transections, one at 10% BL and one at 30% BL, to interrupt long-axon RS neuron projections. At short recovery times (3-5 wk), RS and PS neurons will have regenerated their axons for short distances and potentially established a polysynaptic descending command pathway. At these short recovery times, swimming muscle burst activity had only minor coordination deficits. A computer model that incorporated either of the two spinal lesions could mimic many aspects of the experimental data. In conclusion, descending PS neurons are a viable mechanism for indirect activation of spinal locomotor CPGs, although there can be coordination deficits of locomotor activity. In the lamprey following spinal lesion-mediated interruption of long axonal projections of reticulospinal (RS) neurons, sensory stimulation still elicited relatively normal locomotor muscle burst activity, but with some coordination deficits. Computer models incorporating the spinal lesions could mimic many aspects of the experimental results

  4. Locomotor Dysfunction after Long-duration Space Flight and Development of Countermeasures to Facilitate Faster Recovery

    Science.gov (United States)

    Mulavara, Ajitkumar; Wood, Scott; Cohen, Helen; Bloomberg, Jacob

    2012-07-01

    Exposure to the microgravity conditions of space flight induces adaptive modification in sensorimotor function allowing astronauts to operate in this unique environment. This adaptive state, however, is inappropriate for a 1-g environment. Consequently astronauts must spend time readapting to Earth's gravity following their return to Earth. During this readaptation period, alterations in sensorimotor function cause various disturbances in astronaut gait during postflight walking. They often rely more on vision for postural and gait stability and many report the need for greater cognitive supervision of motor actions that previous to space flight were fully automated. Over the last several years our laboratory has investigated postflight astronaut locomotion with the aim of better understanding how adaptive changes in underlying sensorimotor mechanisms contribute to postflight gait dysfunction. Exposure to the microgravity conditions of space flight induces adaptive modification in the control of vestibularly-mediated reflexive head movement during locomotion after space flight. Furthermore, during motor learning, adaptive transitions are composed of two main mechanisms: strategic and plastic. Strategic mechanisms represent immediate and transitory modifications in control to deal with changes in the prevailing environment that, if prolonged, induce plastic mechanisms designed to automate new behavioral responses. The goal of the present study was to examine the contributions of sensorimotor subsystems such as the vestibular and body load sensing (BLS) somatosensory influences on head movement control during locomotion after long-duration space flight. Further we present data on the two motor learning processes during readaptation of locomotor function after long-duration space flight. Eighteen astronauts performed two tests of locomotion before and after 6 months of space flight: a treadmill walking test to examine vestibular reflexive mechanisms controlling head

  5. Assessment of Postflight Locomotor Performance Utilizing a Test of Functional Mobility: Strategic and Adaptive Responses

    Science.gov (United States)

    Warren, L. E.; Mulavara, A. P.; Peters, B. T.; Cohen, H. S.; Richards, J. T.; Miller, C. A.; Brady, R.; Ruttley, T. M.; Bloomberg, J. J.

    2006-01-01

    Space flight induces adaptive modification in sensorimotor function, allowing crewmembers to operate in the unique microgravity environment. This adaptive state, however, is inappropriate for a terrestrial environment. During a re-adaptation period upon their return to Earth, crewmembers experience alterations in sensorimotor function, causing various disturbances in perception, spatial orientation, posture, gait, and eye-head coordination. Following long duration space flight, sensorimotor dysfunction would prevent or extend the time required to make an emergency egress from the vehicle; compromising crew safety and mission objectives. We are investigating two types of motor learning that may interact with each other and influence a crewmember's ability to re-adapt to Earth's gravity environment. In strategic learning, crewmembers make rapid modifications in their motor control strategy emphasizing error reduction. This type of learning may be critical during the first minutes and hours after landing. In adaptive learning, long-term plastic transformations occur, involving morphological changes and synaptic modification. In recent literature these two behavioral components have been associated with separate brain structures that control the execution of motor strategies: the strategic component was linked to the posterior parietal cortex and the adaptive component was linked to the cerebellum (Pisella, et al. 2004). The goal of this paper was to demonstrate the relative contributions of the strategic and adaptive components to the re-adaptation process in locomotor control after long duration space flight missions on the International Space Station (ISS). The Functional Mobility Test (FMT) was developed to assess crewmember s ability to ambulate postflight from an operational and functional perspective. Sixteen crewmembers were tested preflight (3 sessions) and postflight (days 1, 2, 4, 7, 25) following a long duration space flight (approx 6 months) on the ISS. We

  6. A business analytics capability framework

    Directory of Open Access Journals (Sweden)

    Ranko Cosic

    2015-09-01

    Full Text Available Business analytics (BA capabilities can potentially provide value and lead to better organisational performance. This paper develops a holistic, theoretically-grounded and practically relevant business analytics capability framework (BACF that specifies, defines and ranks the capabilities that constitute an organisational BA initiative. The BACF was developed in two phases. First, an a priori conceptual framework was developed based on the Resource-Based View theory of the firm and a thematic content analysis of the BA literature. Second, the conceptual framework was further developed and refined using a three round Delphi study involving 16 BA experts. Changes from the Delphi study resulted in a refined and confirmed framework including detailed capability definitions, together with a ranking of the capabilities based on importance. The BACF will help academic researchers and industry practitioners to better understand the capabilities that constitute an organisational BA initiative and their relative importance. In future work, the capabilities in the BACF will be operationalised to measure their as-is status, thus enabling organisations to identify key areas of strength and weakness and prioritise future capability improvement efforts.

  7. Identifying 21st Century Capabilities

    Science.gov (United States)

    Stevens, Robert

    2012-01-01

    What are the capabilities necessary to meet 21st century challenges? Much of the literature on 21st century skills focuses on skills necessary to meet those challenges associated with future work in a globalised world. The result is a limited characterisation of those capabilities necessary to address 21st century social, health and particularly…

  8. Developing Collaborative Product Development Capabilities

    DEFF Research Database (Denmark)

    Mahnke, Volker; Tran, Yen

    2012-01-01

    innovation strategies’. Our analyses suggest that developing such collaboration capabilities benefits from the search for complementary practices, the combination of learning styles, and the development of weak and strong ties. Results also underscore the crucial importance of co-evolution of multi......Collaborative product development capabilities support a company’s product innovation activities. In the context of the fast fashion sector, this paper examines the development of the product development capabilities (PDC) that align product development capabilities in a dual innovation context......, one, slow paced, where the firm is well established and the other, fast paced, which represents a new competitive arena in which the company competes. To understand the process associated with collaborative capability development, we studied three Scandinavian fashion companies pursuing ‘dual...

  9. Marketing Capability in Strategy Research

    DEFF Research Database (Denmark)

    Ritter, Thomas; Distel, Andreas Philipp

    Following the call for a demand-side perspective of strategic management (e.g., Priem et al., 2012), a firm’s marketing capability, i.e. its ability to interact with down-stream stakeholders, becomes a pivotal element in explaining a firm’s competitiveness. While marketing capability is recognized...... in the strategic management literature as an important driver of firm performance, our review of 86 articles reveals a lack of a generally accepted definition of marketing capability, a lack of a common conceptualization as well as differences in the measurement of marketing capability. In order to build a common...... ground for advancing marketing capability research and thus supporting the demand-side perspective in strategic management, we develop an integrative framework to explain the differences and propose a research agenda for developing the field....

  10. CRFR1 in the ventromedial caudate putamen modulates acute stress-enhanced expression of cocaine locomotor sensitization.

    Science.gov (United States)

    Liu, Shuli; Wang, Zhiyan; Li, Yijing; Sun, Xiaowei; Ge, Feifei; Yang, Mingda; Wang, Xinjuan; Wang, Na; Wang, Junkai; Cui, Cailian

    2017-07-15

    Repeated exposure to psychostimulants induces a long-lasting enhancement of locomotor activity called behavioral sensitization, which is often reinforced by stress after drug withdrawal. The mechanisms underlying these phenomena remain elusive. Here we explored the effects of acute stress 3 or 14 days after the cessation of chronic cocaine treatment on the expression of locomotor sensitization induced by a cocaine challenge in rats and the key brain region and molecular mechanism underlying the phenomenon. A single session of forced swimming, as an acute stress (administered 2 days after the cessation of cocaine), significantly enhanced the expression of cocaine locomotor sensitization 14 days after the final cocaine injection (challenge at 12 days after acute stress) but not 3 days after the cessation of cocaine (challenge at 1 day after acute stress). The result indicated that acute stress enhanced the expression of cocaine locomotor sensitization after incubation for 12 days rather than 1 day after the last cocaine injection. Moreover, the enhancement in locomotor sensitization was paralleled by a selective increase in the number of the c-Fos + cells, the level of CRFR1 mRNA in the ventromedial caudate putamen (vmCPu). Furthermore, the enhancement was significantly attenuated by CRFR1 antagonist NBI-27914 into the vmCPu, implying that the up-regulation of CRFR1 in the vmCPu seems to be critical in the acute stress-enhanced expression of cocaine locomotor sensitization. The findings demonstrate that the long-term effect of acute stress on the expression of cocaine locomotor sensitization is partially mediated by CRFR1 in the vmCPu. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

  11. Drosophila Clock Is Required in Brain Pacemaker Neurons to Prevent Premature Locomotor Aging Independently of Its Circadian Function.

    Directory of Open Access Journals (Sweden)

    Alexandra Vaccaro

    2017-01-01

    Full Text Available Circadian clocks control many self-sustained rhythms in physiology and behavior with approximately 24-hour periodicity. In many organisms, oxidative stress and aging negatively impact the circadian system and sleep. Conversely, loss of the clock decreases resistance to oxidative stress, and may reduce lifespan and speed up brain aging and neurodegeneration. Here we examined the effects of clock disruptions on locomotor aging and longevity in Drosophila. We found that lifespan was similarly reduced in three arrhythmic mutants (ClkAR, cyc0 and tim0 and in wild-type flies under constant light, which stops the clock. In contrast, ClkAR mutants showed significantly faster age-related locomotor deficits (as monitored by startle-induced climbing than cyc0 and tim0, or than control flies under constant light. Reactive oxygen species accumulated more with age in ClkAR mutant brains, but this did not appear to contribute to the accelerated locomotor decline of the mutant. Clk, but not Cyc, inactivation by RNA interference in the pigment-dispersing factor (PDF-expressing central pacemaker neurons led to similar loss of climbing performance as ClkAR. Conversely, restoring Clk function in these cells was sufficient to rescue the ClkAR locomotor phenotype, independently of behavioral rhythmicity. Accelerated locomotor decline of the ClkAR mutant required expression of the PDF receptor and correlated to an apparent loss of dopaminergic neurons in the posterior protocerebral lateral 1 (PPL1 clusters. This neuronal loss was rescued when the ClkAR mutation was placed in an apoptosis-deficient background. Impairing dopamine synthesis in a single pair of PPL1 neurons that innervate the mushroom bodies accelerated locomotor decline in otherwise wild-type flies. Our results therefore reveal a novel circadian-independent requirement for Clk in brain circadian neurons to maintain a subset of dopaminergic cells and avoid premature locomotor aging in Drosophila.

  12. Capabilities and Incapabilities of the Capabilities Approach to Health Justice.

    Science.gov (United States)

    Selgelid, Michael J

    2016-01-01

    This first part of this article critiques Sridhar Venkatapuram's conception of health as a capability. It argues that Venkatapuram relies on the problematic concept of dignity, implies that those who are unhealthy lack lives worthy of dignity (which seems politically incorrect), sets a low bar for health, appeals to metaphysically problematic thresholds, fails to draw clear connections between appealed-to capabilities and health, and downplays the importance/relevance of health functioning. It concludes by questioning whether justice entitlements should pertain to the capability for health versus health achievements, challenging Venkatapuram's claims about the strength of health entitlements, and demonstrating that the capabilities approach is unnecessary to address social determinants of health. © 2016 John Wiley & Sons Ltd.

  13. Comparison of locomotor behaviour between white-headed langurs Trachypithecus leucocephalus and François’ langurs T. françoisi in Fusui, China

    OpenAIRE

    Jinrong XIONG; Shihua GONG; Chenggang QIU; Zhaoyuan LI

    2009-01-01

    We studied the locomotor behaviour of white-headed langurs Trachypithecus leucocephalus and François’ langurs T.françoisi to test two hypotheses: (1) these monkeys have evolved locomotor ability to support their activities on limestone hills, and (2) François’ langurs have evolved more diverse locomotor skills than white-headed langurs. Data were collected from 1996–1998 and in 2005 in Fusui Nature Reserve, Guangxi, and showed that the two species had similar locomotor types, but François’ l...

  14. Indigenous Technological Innovation : Capability and ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Indigenous Technological Innovation : Capability and Competitiveness in China's ... IDRC and key partners will showcase critical work on adaptation and ... Call for new OWSD Fellowships for Early Career Women Scientists now open.

  15. Earth Science Capability Demonstration Project

    Science.gov (United States)

    Cobleigh, Brent

    2006-01-01

    A viewgraph presentation reviewing the Earth Science Capability Demonstration Project is shown. The contents include: 1) ESCD Project; 2) Available Flight Assets; 3) Ikhana Procurement; 4) GCS Layout; 5) Baseline Predator B Architecture; 6) Ikhana Architecture; 7) UAV Capability Assessment; 8) The Big Picture; 9) NASA/NOAA UAV Demo (5/05 to 9/05); 10) NASA/USFS Western States Fire Mission (8/06); and 11) Suborbital Telepresence.

  16. Poststroke Hemiparesis Impairs the Rate but not Magnitude of Adaptation of Spatial and Temporal Locomotor Features

    Science.gov (United States)

    Savin, Douglas N.; Tseng, Shih-Chiao; Whitall, Jill; Morton, Susanne M.

    2015-01-01

    Background Persons with stroke and hemiparesis walk with a characteristic pattern of spatial and temporal asymmetry that is resistant to most traditional interventions. It was recently shown in nondisabled persons that the degree of walking symmetry can be readily altered via locomotor adaptation. However, it is unclear whether stroke-related brain damage affects the ability to adapt spatial or temporal gait symmetry. Objective Determine whether locomotor adaptation to a novel swing phase perturbation is impaired in persons with chronic stroke and hemiparesis. Methods Participants with ischemic stroke (14) and nondisabled controls (12) walked on a treadmill before, during, and after adaptation to a unilateral perturbing weight that resisted forward leg movement. Leg kinematics were measured bilaterally, including step length and single-limb support (SLS) time symmetry, limb angle center of oscillation, and interlimb phasing, and magnitude of “initial” and “late” locomotor adaptation rates were determined. Results All participants had similar magnitudes of adaptation and similar initial adaptation rates both spatially and temporally. All 14 participants with stroke and baseline asymmetry temporarily walked with improved SLS time symmetry after adaptation. However, late adaptation rates poststroke were decreased (took more strides to achieve adaptation) compared with controls. Conclusions Mild to moderate hemiparesis does not interfere with the initial acquisition of novel symmetrical gait patterns in both the spatial and temporal domains, though it does disrupt the rate at which “late” adaptive changes are produced. Impairment of the late, slow phase of learning may be an important rehabilitation consideration in this patient population. PMID:22367915

  17. Analysis of Indonesian Spice Essential Oil Compounds That Inhibit Locomotor Activity in Mice

    Directory of Open Access Journals (Sweden)

    Anas Subarnas

    2011-04-01

    Full Text Available Some fragrance components of spices used for cooking are known to have an effect on human behavior. The aim of this investigation was to examine the effect of the essential oils of basil (Ocimum formacitratum L. leaves, lemongrass (Cymbopogon citrates L. herbs, ki lemo (Litsea cubeba L. bark, and laja gowah (Alpinia malaccencis Roxb. rhizomes on locomotor activity in mice and identify the active component(s that might be responsible for the activity. The effect of the essential oils was studied by a wheel cage method and the active compounds of the essential oils were identified by GC/MS analysis. The essential oils were administered by inhalation at doses of 0.1, 0.3, and 0.5 mL/cage. The results showed that the four essential oils had inhibitory effects on locomotor activity in mice. Inhalation of the essential oils of basil leaves, lemongrass herbs, ki lemo bark, and laja gowah rhizomes showed the highest inhibitory activity at doses of 0.5 (57.64%, 0.1 (55.72%, 0.5 (60.75%, and 0.1 mL/cage (47.09%, respectively. The major volatile compounds 1,8-cineole, α-terpineol, 4-terpineol, citronelol, citronelal, and methyl cinnamate were identified in blood plasma of mice after inhalation of the four oils. These compounds had a significant inhibitory effect on locomotion after inhalation. The volatile compounds of essential oils identified in the blood plasma may correlate with the locomotor-inhibiting properties of the oil when administered by inhalation.

  18. Developmental Deltamethrin Exposure Causes Persistent Changes in Dopaminergic Gene Expression, Neurochemistry, and Locomotor Activity in Zebrafish.

    Science.gov (United States)

    Kung, Tiffany S; Richardson, Jason R; Cooper, Keith R; White, Lori A

    2015-08-01

    Pyrethroids are commonly used insecticides that are considered to pose little risk to human health. However, there is an increasing concern that children are more susceptible to the adverse effects of pesticides. We used the zebrafish model to test the hypothesis that developmental exposure to low doses of the pyrethroid deltamethrin results in persistent alterations in dopaminergic gene expression, neurochemistry, and locomotor activity. Zebrafish embryos were treated with deltamethrin (0.25-0.50 μg/l), at concentrations below the LOAEL, during the embryonic period [3-72 h postfertilization (hpf)], after which transferred to fresh water until the larval stage (2-weeks postfertilization). Deltamethrin exposure resulted in decreased transcript levels of the D1 dopamine (DA) receptor (drd1) and increased levels of tyrosine hydroxylase at 72 hpf. The reduction in drd1 transcripts persisted to the larval stage and was associated with decreased D2 dopamine receptor transcripts. Larval fish, exposed developmentally to deltamethrin, had increased levels of homovanillic acid, a DA metabolite. Since the DA system is involved in locomotor activity, we measured the swim activity of larval fish following a transition to darkness. Developmental exposure to deltamethrin significantly increased larval swim activity which was attenuated by concomitant knockdown of the DA transporter. Acute exposure to methylphenidate, a DA transporter inhibitor, increased swim activity in control larva, while reducing swim activity in larva developmentally exposed to deltamethrin. Developmental exposure to deltamethrin causes locomotor deficits in larval zebrafish, which is likely mediated by dopaminergic dysfunction. This highlights the need to understand the persistent effects of low-dose neurotoxicant exposure during development. © The Author 2015. Published by Oxford University Press on behalf of the Society of Toxicology. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

  19. Perceptual-motor regulation in locomotor pointing while approaching a curb.

    Science.gov (United States)

    Andel, Steven van; Cole, Michael H; Pepping, Gert-Jan

    2018-02-01

    Locomotor pointing is a task that has been the focus of research in the context of sport (e.g. long jumping and cricket) as well as normal walking. Collectively, these studies have produced a broad understanding of locomotor pointing, but generalizability has been limited to laboratory type tasks and/or tasks with high spatial demands. The current study aimed to generalize previous findings in locomotor pointing to the common daily task of approaching and stepping on to a curb. Sixteen people completed 33 repetitions of a task that required them to walk up to and step onto a curb. Information about their foot placement was collected using a combination of measures derived from a pressure-sensitive walkway and video data. Variables related to perceptual-motor regulation were analyzed on an inter-trial, intra-step and inter-step level. Similar to previous studies, analysis of the foot placements showed that, variability in foot placement decreased as the participants drew closer to the curb. Regulation seemed to be initiated earlier in this study compared to previous studies, as shown by a decreasing variability in foot placement as early as eight steps before reaching the curb. Furthermore, it was shown that when walking up to the curb, most people regulated their walk in a way so as to achieve minimal variability in the foot placement on top of the curb, rather than a placement in front of the curb. Combined, these results showed a strong perceptual-motor coupling in the task of approaching and stepping up a curb, rendering this task a suitable test for perceptual-motor regulation in walking. Copyright © 2017 Elsevier B.V. All rights reserved.

  20. Individual differences in circadian locomotor parameters correlate with anxiety- and depression-like behavior.

    Directory of Open Access Journals (Sweden)

    Jeffrey Anyan

    Full Text Available Disrupted circadian rhythms are a core feature of mood and anxiety disorders. Circadian rhythms are coordinated by a light-entrainable master clock located in the suprachiasmatic nucleus. Animal models of mood and anxiety disorders often exhibit blunted rhythms in locomotor activity and clock gene expression. Interestingly, the changes in circadian rhythms correlate with mood-related behaviours. Although animal models of depression and anxiety exhibit aberrant circadian rhythms in physiology and behavior, it is possible that the methodology being used to induce the behavioral phenotype (e.g., brain lesions, chronic stress, global gene deletion affect behavior independently of circadian system. This study investigates the relationship between individual differences in circadian locomotor parameters and mood-related behaviors in healthy rats. The circadian phenotype of male Lewis rats was characterized by analyzing wheel running behavior under standard 12h:12h LD conditions, constant dark, constant light, and rate of re-entrainment to a phase advance. Rats were then tested on a battery of behavioral tests: activity box, restricted feeding, elevated plus maze, forced swim test, and fear conditioning. Under 12h:12h LD conditions, percent of daily activity in the light phase and variability in activity onset were associated with longer latency to immobility in the forced swim test. Variability in onset also correlated positively with anxiety-like behavior in the elevated plus maze. Rate of re-entrainment correlated positively with measures of anxiety in the activity box and elevated plus maze. Lastly, we found that free running period under constant dark was associated with anxiety-like behaviors in the activity box and elevated plus maze. Our results provide a previously uncharacterized relationship between circadian locomotor parameters and mood-related behaviors in healthy rats and provide a basis for future examination into circadian clock

  1. Limb Bone Structural Proportions and Locomotor Behavior in A.L. 288-1 ("Lucy".

    Directory of Open Access Journals (Sweden)

    Christopher B Ruff

    Full Text Available While there is broad agreement that early hominins practiced some form of terrestrial bipedality, there is also evidence that arboreal behavior remained a part of the locomotor repertoire in some taxa, and that bipedal locomotion may not have been identical to that of modern humans. It has been difficult to evaluate such evidence, however, because of the possibility that early hominins retained primitive traits (such as relatively long upper limbs of little contemporaneous adaptive significance. Here we examine bone structural properties of the femur and humerus in the Australopithecus afarensis A.L. 288-1 ("Lucy", 3.2 Myr that are known to be developmentally plastic, and compare them with other early hominins, modern humans, and modern chimpanzees. Cross-sectional images were obtained from micro-CT scans of the original specimens and used to derive section properties of the diaphyses, as well as superior and inferior cortical thicknesses of the femoral neck. A.L. 288-1 shows femoral/humeral diaphyseal strength proportions that are intermediate between those of modern humans and chimpanzees, indicating more mechanical loading of the forelimb than in modern humans, and by implication, a significant arboreal locomotor component. Several features of the proximal femur in A.L. 288-1 and other australopiths, including relative femoral head size, distribution of cortical bone in the femoral neck, and cross-sectional shape of the proximal shaft, support the inference of a bipedal gait pattern that differed slightly from that of modern humans, involving more lateral deviation of the body center of mass over the support limb, which would have entailed increased cost of terrestrial locomotion. There is also evidence consistent with increased muscular strength among australopiths in both the forelimb and hind limb, possibly reflecting metabolic trade-offs between muscle and brain development during hominin evolution. Together these findings imply

  2. Circadian locomotor rhythms in the cricket, Gryllodes sigillatus. I. Localization of the pacemaker and the photoreceptor.

    Science.gov (United States)

    Abe, Y; Ushirogawa, H; Tomioka, K

    1997-10-01

    Circadian locomotor rhythm and its underlying mechanism were investigated in the cricket, Gryllodes sigillatus. Adult male crickets showed a nocturnal locomotor rhythm peaking early in the dark phase of a light to dark cycle. This rhythm persisted under constant darkness (DD) with a free-running period averaging 23.1 +/- 0.3 hr. Although constant bright light made most animals arrhythmic, about 40% of the animals showed free-running rhythms with a period longer than 24 hr under constant dim light condition. On transfer to DD, all arrhythmic animals restored the locomotor rhythm. Bilateral optic nerve severance resulted in free-running of the rhythm even under light-dark cycles. The free-running period of the optic nerve severed animals was significantly longer than sham operated crickets in DD, suggesting that the compound eye plays some role in determining the free-running period. Removal of bilateral lamina-medulla portion of the optic lobe abolished the rhythm under DD. These results demonstrate that the photoreceptor for entrainment is the compound eye and the optic lobe is indispensable for persistence of the rhythm. However, 75% and 54% of the optic lobeless animals showed aberrant rhythms with a period very close to 24 hr under light and temperature cycles, respectively, suggesting that there are neural and/or humoral mechanisms for the aberrant rhythms outside of the optic lobe. Since ocelli removal did not affect the photoperiodically induced rhythm, it is likely that the photoreception for the rhythm is performed through an extraretinal photoreceptor.

  3. The effects of opioid drugs on dopamine mediated locomotor activity in rats

    International Nuclear Information System (INIS)

    Leathern, L.L.

    1986-12-01

    Opioid drugs influence various behavioural parameters including locomotor activity in experimental animals. The interaction between the opioid and dopaminergic systems is one possible explanation for the effect of opioid drugs on locomotor activity. In this study behavioural and biochemical assays were done to investigate the interaction between the opioid and dopaminergic systems. Behavioural studies were done by measurement of locomotor activity (LA) of rats after acute or chronic pretreatment with opioid and/or dopaminergic drugs. Biochemical studies were in the form of radioligand binding assays, the effect on the number (Bmax) and affinity (K D ) of receptors was measured after chronic pretreatment with opioid and/or dopaminergic drugs. The opioid drugs used are morphine, nalbuphine and naloxone. Dopaminergic drugs used included: agonists-apomorphine and piribedil; antagonists-pimozide, haloperidol, chlorpromazine. In the acute situation increased LA was obtained with morphine and the DA agonists. A correlation between the behavioural and biochemical assays was found. Chronic pretreatment with morphine enhanced apomorphine induced LA, this supersensitivity was also measured as an increased receptor density (Bmax) of D2 receptors in the striatum. Chronic morphine pretreatment caused a decrease in morphine induced LA, while this subsensitivity was not apparent in the ligand binding assays - where no change in receptor number was observed. Chronic naloxone pretreatment enhanced morphine induced LA, as well as increased the Bmax of opioid receptors in the whole brain. It is concluded that an interaction between the opioid and dopaminergic systems does exist, and may account for the mechanism of action of the opioids

  4. Analysis of Indonesian Spice Essential Oil Compounds That Inhibit Locomotor Activity in Mice

    Science.gov (United States)

    Muchtaridi; Diantini, Adjeng; Subarnas, Anas

    2011-01-01

    Some fragrance components of spices used for cooking are known to have an effect on human behavior. The aim of this investigation was to examine the effect of the essential oils of basil (Ocimum formacitratum L.) leaves, lemongrass (Cymbopogon citrates L.) herbs, ki lemo (Litsea cubeba L.) bark, and laja gowah (Alpinia malaccencis Roxb.) rhizomes on locomotor activity in mice and identify the active component(s) that might be responsible for the activity. The effect of the essential oils was studied by a wheel cage method and the active compounds of the essential oils were identified by GC/MS analysis. The essential oils were administered by inhalation at doses of 0.1, 0.3, and 0.5 mL/cage. The results showed that the four essential oils had inhibitory effects on locomotor activity in mice. Inhalation of the essential oils of basil leaves, lemongrass herbs, ki lemo bark, and laja gowah rhizomes showed the highest inhibitory activity at doses of 0.5 (57.64%), 0.1 (55.72%), 0.5 (60.75%), and 0.1 mL/cage (47.09%), respectively. The major volatile compounds 1,8-cineole, α-terpineol, 4-terpineol, citronelol, citronelal, and methyl cinnamate were identified in blood plasma of mice after inhalation of the four oils. These compounds had a significant inhibitory effect on locomotion after inhalation. The volatile compounds of essential oils identified in the blood plasma may correlate with the locomotor-inhibiting properties of the oil when administered by inhalation.

  5. Transgenic APP expression during postnatal development causes persistent locomotor hyperactivity in the adult.

    Science.gov (United States)

    Rodgers, Shaefali P; Born, Heather A; Das, Pritam; Jankowsky, Joanna L

    2012-06-18

    Transgenic mice expressing disease-associated proteins have become standard tools for studying human neurological disorders. Transgenes are often expressed using promoters chosen to drive continuous high-level expression throughout life rather than temporal and spatial fidelity to the endogenous gene. This approach has allowed us to recapitulate diseases of aging within the two-year lifespan of the laboratory mouse, but has the potential for creating aberrant phenotypes by mechanisms unrelated to the human disorder. We show that overexpression of the Alzheimer's-related amyloid precursor protein (APP) during early postnatal development leads to severe locomotor hyperactivity that can be significantly attenuated by delaying transgene onset until adulthood. Our data suggest that exposure to transgenic APP during maturation influences the development of neuronal circuits controlling motor activity. Both when matched for total duration of APP overexpression and when matched for cortical amyloid burden, animals exposed to transgenic APP as juveniles are more active in locomotor assays than animals in which APP overexpression was delayed until adulthood. In contrast to motor activity, the age of APP onset had no effect on thigmotaxis in the open field as a rough measure of anxiety, suggesting that the interaction between APP overexpression and brain development is not unilateral. Our findings indicate that locomotor hyperactivity displayed by the tet-off APP transgenic mice and several other transgenic models of Alzheimer's disease may result from overexpression of mutant APP during postnatal brain development. Our results serve as a reminder of the potential for unexpected interactions between foreign transgenes and brain development to cause long-lasting effects on neuronal function in the adult. The tet-off APP model provides an easy means of avoiding developmental confounds by allowing transgene expression to be delayed until the mice reach adulthood.

  6. Limited interlimb transfer of locomotor adaptations to a velocity-dependent force field during unipedal walking.

    Science.gov (United States)

    Houldin, Adina; Chua, Romeo; Carpenter, Mark G; Lam, Tania

    2012-08-01

    Several studies have demonstrated that motor adaptations to a novel task environment can be transferred between limbs. Such interlimb transfer of motor commands is consistent with the notion of centrally driven strategies that can be generalized across different frames of reference. So far, studies of interlimb transfer of locomotor adaptations have yielded disparate results. Here we sought to determine whether locomotor adaptations in one (trained) leg show transfer to the other (test) leg during a unipedal walking task. We hypothesized that adaptation in the test leg to a velocity-dependent force field previously experienced by the trained leg will be faster, as revealed by faster recovery of kinematic errors and earlier onset of aftereffects. Twenty able-bodied adults walked unipedally in the Lokomat robotic gait orthosis, which applied velocity-dependent resistance to the legs. The amount of resistance was scaled to 10% of each individual's maximum voluntary contraction of the hip flexors. Electromyography and kinematics of the lower limb were recorded. All subjects were right-leg dominant and were tested for transfer of motor adaptations from the right leg to the left leg. Catch trials, consisting of unexpected removal of resistance, were presented after the first step with resistance and after a period of adaptation to test for aftereffects. We found no significant differences in the sizes of the aftereffects between the two legs, except for peak hip flexion during swing, or in the rate at which peak hip flexion adapted during steps against resistance between the two legs. Our results indicate that interlimb transfer of these types of locomotor adaptation is not a robust phenomenon. These findings add to our current understanding of motor adaptations and provide further evidence that generalization of adaptations may be dependent on the movement task.

  7. Local field potentials in the ventral tegmental area during cocaine-induced locomotor activation: Measurements in freely moving rats.

    Science.gov (United States)

    Harris Bozer, Amber L; Li, Ai-Ling; Sibi, Jiny E; Bobzean, Samara A M; Peng, Yuan B; Perrotti, Linda I

    2016-03-01

    The ventral tegmental area (VTA) has been established as a critical nucleus for processing behavioral changes that occur during psychostimulant use. Although it is known that cocaine induced locomotor activity is initiated in the VTA, not much is known about the electrical activity in real time. The use of our custom-designed wireless module for recording local field potential (LFP) activity provides an opportunity to confirm and identify changes in neuronal activity within the VTA of freely moving rats. The purpose of this study was to investigate the changes in VTA LFP activity in real time that underlie cocaine induced changes in locomotor behavior. Recording electrodes were implanted in the VTA of rats. Locomotor behavior and LFP activity were simultaneously recorded at baseline, and after saline and cocaine injections. Results indicate that cocaine treatment caused increases in both locomotor behavior and LFP activity in the VTA. Specifically, LFP activity was highest during the first 30 min following the cocaine injection and was most robust in Delta and Theta frequency bands; indicating the role of low frequency VTA activity in the initiation of acute stimulant-induced locomotor behavior. Our results suggest that LFP recording in freely moving animals can be used in the future to provide valuable information pertaining to drug induced changes in neural activity. Copyright © 2016 Elsevier Inc. All rights reserved.

  8. Integration of Descending Command Systems for the Generation of Context-Specific Locomotor Behaviors

    Directory of Open Access Journals (Sweden)

    Linda H. Kim

    2017-10-01

    Full Text Available Over the past decade there has been a renaissance in our understanding of spinal cord circuits; new technologies are beginning to provide key insights into descending circuits which project onto spinal cord central pattern generators. By integrating work from both the locomotor and animal behavioral fields, we can now examine context-specific control of locomotion, with an emphasis on descending modulation arising from various regions of the brainstem. Here we examine approach and avoidance behaviors and the circuits that lead to the production and arrest of locomotion.

  9. Human spinal locomotor control is based on flexibly organized burst generators.

    Science.gov (United States)

    Danner, Simon M; Hofstoetter, Ursula S; Freundl, Brigitta; Binder, Heinrich; Mayr, Winfried; Rattay, Frank; Minassian, Karen

    2015-03-01

    Constant drive provided to the human lumbar spinal cord by epidural electrical stimulation can cause local neural circuits to generate rhythmic motor outputs to lower limb muscles in people paralysed by spinal cord injury. Epidural spinal cord stimulation thus allows the study of spinal rhythm and pattern generating circuits without their configuration by volitional motor tasks or task-specific peripheral feedback. To reveal spinal locomotor control principles, we studied the repertoire of rhythmic patterns that can be generated by the functionally isolated human lumbar spinal cord, detected as electromyographic activity from the legs, and investigated basic temporal components shared across these patterns. Ten subjects with chronic, motor-complete spinal cord injury were studied. Surface electromyographic responses to lumbar spinal cord stimulation were collected from quadriceps, hamstrings, tibialis anterior, and triceps surae in the supine position. From these data, 10-s segments of rhythmic activity present in the four muscle groups of one limb were extracted. Such samples were found in seven subjects. Physiologically adequate cycle durations and relative extension- and flexion-phase durations similar to those needed for locomotion were generated. The multi-muscle activation patterns exhibited a variety of coactivation, mixed-synergy and locomotor-like configurations. Statistical decomposition of the electromyographic data across subjects, muscles and samples of rhythmic patterns identified three common temporal components, i.e. basic or shared activation patterns. Two of these basic patterns controlled muscles to contract either synchronously or alternatingly during extension- and flexion-like phases. The third basic pattern contributed to the observed muscle activities independently from these extensor- and flexor-related basic patterns. Each bifunctional muscle group was able to express both extensor- and flexor-patterns, with variable ratios across the

  10. [INFLUENCE OF IONIZING RADIATION ON THE LOCOMOTOR ACTIVITY AND BODY WEIGHT OF RATS].

    Science.gov (United States)

    Saimova, A; Chaizhunusоva, N; Kairkhanova, Y; Uzbеkоv, D; Hоshi, М

    2017-02-01

    The aim of our study was to study influence of ionizing radiation on the locomotor activity and body weight of rats, for this animals was irradiated by via inhalation. Beta- emitter 56Mn was obtained by neutron activation of powdered MnО2 by using nuclear reactor IVG.1M (experimental facility «Baikal-1», Kurchatov, Kazakhstan). Exposure of rats to radioactive powder had two way, the first experiment was contained only air filter for animal's breathing and the second with the system of forced ventilation. Also we developed the method for observation of the locomotor activity of rats, based on quantitative data. The experiment was conducted on 8 «Wistar» breed white laboratory rats. Statistical analysis was performed using descriptive statistics and non-parametric test. Based on our data, we can say that our method has the advantage over the others is that there is no need to move about the animal out of the box in the test field. So we reduce animal stress factor, as the transfer of an animal from one to second place creates additional stress for him. The initial activity of the pulverized powder in both experiments were 2,74х108Bq, but in the second experiment when we used the system of forced ventilation, internal radiation doses were 0.041±0.0075 Gy, this didn't have effect on locomotor activity of rats (Z= -0,841, р=0,4). In the first experiment where we used only air filter for animal's breathing internal radiation doses were 0.15±0.025 Gr, that showed a decrease in locomotor activity in rats (Z=-6,653, р=0,001). After exposure to ionizing radiation changes in the mammals' weight were not found. Thus, based on our data we have made conclusion, that even after a single irradiation at low dose 0.15±0.025 Gr changes occur in the nervous system.

  11. A rapid enhancement of locomotor sensitization to amphetamine by estradiol in female rats.

    Science.gov (United States)

    Zovkic, Iva B; McCormick, Cheryl M

    2017-11-14

    Estradiol moderates the effects of drugs of abuse in both humans and rodents. Estradiol's enhancement of behavioral effects resulting from high (>2.5mg/kg) doses of amphetamine is established in rats; there is less evidence for the role of estradiol in locomotor effects elicited by lower doses, which are less aversive, increase incentive motivation, involve different neural mechanisms than higher doses, and often more readily reveal group differences than do higher doses. Further, the extent to which estradiol is required for the induction versus the expression of sensitization is unknown. To establish a protocol, we replicated the effects of estradiol on locomotor sensitization to amphetamine reported in a previous study that involved a high locomotor-activating dose (1.5mg/kg) of amphetamine, but with a lower dose. Ovariectomized female rats received 5μg of estradiol benzoate (EB) or OIL 30min before each of 5 treatments of 1.0mg/kg amphetamine or saline; all received a 0.5mg/kg challenge dose three days later. Compared with results for OIL, EB enhanced the locomotor-activating effects of repeated 1.0mg/kg amphetamine across treatment days. In contrast, on challenge day, there was no difference between EB-saline and EB-amphetamine to the lower dose (i.e., no sensitization). Experiments 2 and 3 involved a shorter induction (2days) and a lengthier withdrawal (9days) before the challenge test for the expression of sensitization to better differentiate the induction phase from the expression phase. In Expt2, EB-, and not OIL-, treated rats showed sensitization to 0.5mg/kg amphetamine; neither group showed sensitization to 1.5mg/kg amphetamine (ceiling effect?). In Expt3, rats were treated with EB either in both the induction and expression phases, in one of the phases only, or in neither phase. There was an effect of hormone treatment on challenge day and not on induction day; rats given EB on Challenge day showed sensitization to 0.5mg/kg amphetamine; OIL rats did

  12. Impairment of the organization of locomotor and exploratory behaviors in bile duct-ligated rats

    DEFF Research Database (Denmark)

    Leke, Renata; de Oliveira, Diogo L; Mussulini, Ben Hur M.

    2012-01-01

    Hepatic encephalopathy (HE) arises from acute or chronic liver diseases and leads to several problems, including motor impairment. Animal models of chronic liver disease have extensively investigated the mechanisms of this disease. Impairment of locomotor activity has been described in different...... female Wistar rats underwent common bile duct ligation (BDL rats) or the manipulation of common bile duct without ligation (control rats). Six weeks after surgery, control and BDL rats underwent open-field, plus-maze and foot-fault behavioral tasks. The BDL rats developed chronic liver failure...

  13. Oxytocin decreases cocaine taking, cocaine seeking, and locomotor activity in female rats

    OpenAIRE

    Leong, Kah-Chung; Zhou, Luyi; Ghee, Shannon M.; See, Ronald E.; Reichel, Carmela M.

    2016-01-01

    Oxytocin has been shown to decrease cocaine taking and seeking in male rats, suggesting potential treatment efficacy for drug addiction. In the present study, we extended these findings to the assessment of cocaine seeking and taking in female rats. Further, we made direct comparisons of oxytocin’s impact on cocaine induced locomotor activity in both males and females. In females, systemic oxytocin (0.3, 1.0, 3.0 mg/kg) attenuated lever pressing for cocaine during self-administration and oxyt...

  14. Clinical efficiency of roentgenopaque study of muscles in patients with disorders of locomotor system

    International Nuclear Information System (INIS)

    D'yachkova, G.V.

    1996-01-01

    Radiopaque studies of soft tissues in patients with disorders and diseases of locomotor system in the case of perosseous osteosynthesis were performed. To correct the diagnosis, control the soft tissue state during treatment, assess its results more than 1000 radiopaque studies of muscles were conducted. Application of the radiopaque studies of femur muscles in patients with extension contractures of knee joint permitted to specify the character of contracture, to determine the character of muscles changes in patients with immobilization and arthrogenetic contractures which depended on disease duration

  15. Locomotor Adaptation Improves Balance Control, Multitasking Ability and Reduces the Metabolic Cost of Postural Instability

    Science.gov (United States)

    Bloomberg, J. J.; Peters, B. T.; Mulavara, A. P.; Brady, R. A.; Batson, C. D.; Miller, C. A.; Ploutz-Snyder, R. J.; Guined, J. R.; Buxton, R. E.; Cohen, H. S.

    2011-01-01

    During exploration-class missions, sensorimotor disturbances may lead to disruption in the ability to ambulate and perform functional tasks during the initial introduction to a novel gravitational environment following a landing on a planetary surface. The overall goal of our current project is to develop a sensorimotor adaptability training program to facilitate rapid adaptation to these environments. We have developed a unique training system comprised of a treadmill placed on a motion-base facing a virtual visual scene. It provides an unstable walking surface combined with incongruent visual flow designed to enhance sensorimotor adaptability. Greater metabolic cost incurred during balance instability means more physical work is required during adaptation to new environments possibly affecting crewmembers? ability to perform mission critical tasks during early surface operations on planetary expeditions. The goal of this study was to characterize adaptation to a discordant sensory challenge across a number of performance modalities including locomotor stability, multi-tasking ability and metabolic cost. METHODS: Subjects (n=15) walked (4.0 km/h) on a treadmill for an 8 -minute baseline walking period followed by 20-minutes of walking (4.0 km/h) with support surface motion (0.3 Hz, sinusoidal lateral motion, peak amplitude 25.4 cm) provided by the treadmill/motion-base system. Stride frequency and auditory reaction time were collected as measures of locomotor stability and multi-tasking ability, respectively. Metabolic data (VO2) were collected via a portable metabolic gas analysis system. RESULTS: At the onset of lateral support surface motion, subj ects walking on our treadmill showed an increase in stride frequency and auditory reaction time indicating initial balance and multi-tasking disturbances. During the 20-minute adaptation period, balance control and multi-tasking performance improved. Similarly, throughout the 20-minute adaptation period, VO2 gradually

  16. Locomotor activity and tissue levels following acute administration of lambda- and gamma-cyhalothrin in rats

    Energy Technology Data Exchange (ETDEWEB)

    Moser, Virginia C., E-mail: Moser.ginger@epa.gov [Toxicity Assessment Division, National Health Effects and Environmental Research Laboratory, Office of Research and Development, US Environmental Protection Agency, Research Triangle Park, NC (United States); Liu, Zhiwei [FMC Corporation, 701 Princeton South Corporate Center, Ewing, NJ (United States); Schlosser, Christopher [Health Effects Division, Office of Pesticide Programs, Office of Chemical Safety and Pollution Prevention, US Environmental Protection Agency, Washington, DC (United States); Spanogle, Terri L.; Chandrasekaran, Appavu [FMC Corporation, 701 Princeton South Corporate Center, Ewing, NJ (United States); McDaniel, Katherine L. [Toxicity Assessment Division, National Health Effects and Environmental Research Laboratory, Office of Research and Development, US Environmental Protection Agency, Research Triangle Park, NC (United States)

    2016-12-15

    Pyrethroids produce neurotoxicity that depends, in part, on the chemical structure. Common behavioral effects include locomotor activity changes and specific toxic syndromes (types I and II). In general these neurobehavioral effects correlate well with peak internal dose metrics. Products of cyhalothrin, a type II pyrethroid, include mixtures of isomers (e.g., λ-cyhalothrin) as well as enriched active isomers (e.g., γ-cyhalothrin). We measured acute changes in locomotor activity in adult male rats and directly correlated these changes to peak brain and plasma concentrations of λ- and γ-cyhalothrin using a within-subject design. One-hour locomotor activity studies were conducted 1.5 h after oral gavage dosing, and immediately thereafter plasma and brains were collected for analyzing tissue levels using LC/MS/MS methods. Both isomers produced dose-related decreases in activity counts, and the effective dose range for γ-cyhalothrin was lower than for λ-cyhalothrin. Doses calculated to decrease activity by 50% were 2-fold lower for the γ-isomer (1.29 mg/kg) compared to λ-cyhalothrin (2.65 mg/kg). Salivation, typical of type II pyrethroids, was also observed at lower doses of γ-cyhalothrin. Administered dose correlated well with brain and plasma concentrations, which furthermore showed good correlations with activity changes. Brain and plasma levels were tightly correlated across doses. While γ-cyhalothrin was 2-fold more potent based on administered dose, the differences based on internal concentrations were less, with γ-cyhalothrin being 1.3- to 1.6-fold more potent than λ-cyhalothrin. These potency differences are consistent with the purity of the λ-isomer (approximately 43%) compared to the enriched isomer γ-cyhalothrin (approximately 98%). Thus, administered dose as well as differences in cyhalothrin isomers is a good predictor of behavioral effects. - Highlights: • Acute changes in locomotor activity were produced by λ- and γ-cyhalothrin. •

  17. Accelerator and Electrodynamics Capability Review

    International Nuclear Information System (INIS)

    Jones, Kevin W.

    2010-01-01

    Los Alamos National Laboratory (LANL) uses capability reviews to assess the science, technology and engineering (STE) quality and institutional integration and to advise Laboratory Management on the current and future health of the STE. Capability reviews address the STE integration that LANL uses to meet mission requirements. The Capability Review Committees serve a dual role of providing assessment of the Laboratory's technical contributions and integration towards its missions and providing advice to Laboratory Management. The assessments and advice are documented in reports prepared by the Capability Review Committees that are delivered to the Director and to the Principal Associate Director for Science, Technology and Engineering (PADSTE). Laboratory Management will use this report for STE assessment and planning. LANL has defined fifteen STE capabilities. Electrodynamics and Accelerators is one of the seven STE capabilities that LANL Management (Director, PADSTE, technical Associate Directors) has identified for review in Fiscal Year (FY) 2010. Accelerators and electrodynamics at LANL comprise a blend of large-scale facilities and innovative small-scale research with a growing focus on national security applications. This review is organized into five topical areas: (1) Free Electron Lasers; (2) Linear Accelerator Science and Technology; (3) Advanced Electromagnetics; (4) Next Generation Accelerator Concepts; and (5) National Security Accelerator Applications. The focus is on innovative technology with an emphasis on applications relevant to Laboratory mission. The role of Laboratory Directed Research and Development (LDRD) in support of accelerators/electrodynamics will be discussed. The review provides an opportunity for interaction with early career staff. Program sponsors and customers will provide their input on the value of the accelerator and electrodynamics capability to the Laboratory mission.

  18. Accelerator and electrodynamics capability review

    Energy Technology Data Exchange (ETDEWEB)

    Jones, Kevin W [Los Alamos National Laboratory

    2010-01-01

    Los Alamos National Laboratory (LANL) uses capability reviews to assess the science, technology and engineering (STE) quality and institutional integration and to advise Laboratory Management on the current and future health of the STE. Capability reviews address the STE integration that LANL uses to meet mission requirements. The Capability Review Committees serve a dual role of providing assessment of the Laboratory's technical contributions and integration towards its missions and providing advice to Laboratory Management. The assessments and advice are documented in reports prepared by the Capability Review Committees that are delivered to the Director and to the Principal Associate Director for Science, Technology and Engineering (PADSTE). Laboratory Management will use this report for STE assessment and planning. LANL has defined fifteen STE capabilities. Electrodynamics and Accelerators is one of the seven STE capabilities that LANL Management (Director, PADSTE, technical Associate Directors) has identified for review in Fiscal Year (FY) 2010. Accelerators and electrodynamics at LANL comprise a blend of large-scale facilities and innovative small-scale research with a growing focus on national security applications. This review is organized into five topical areas: (1) Free Electron Lasers; (2) Linear Accelerator Science and Technology; (3) Advanced Electromagnetics; (4) Next Generation Accelerator Concepts; and (5) National Security Accelerator Applications. The focus is on innovative technology with an emphasis on applications relevant to Laboratory mission. The role of Laboratory Directed Research and Development (LDRD) in support of accelerators/electrodynamics will be discussed. The review provides an opportunity for interaction with early career staff. Program sponsors and customers will provide their input on the value of the accelerator and electrodynamics capability to the Laboratory mission.

  19. The effects of sex-ratio and density on locomotor activity in the house fly, Musca domestica

    DEFF Research Database (Denmark)

    Bahrndorff, Simon; Kjaersgaard, Anders; Pertoldi, Cino

    2012-01-01

    Although locomotor activity is involved in almost all behavioral traits, there is a lack of knowledge on what factors affect it. This study examined the effects of sex-ratio and density on the circadian rhythm of locomotor activity of adult Musca domestica L. (Diptera: Muscidae) using an infra......-red light system. Sex-ratio significantly affected locomotor activity, increasing with the percentage of males in the vials. In accordance with other studies, males were more active than females, but the circadian rhythm of the two sexes was not constant over time and changed during the light period...... of the behavioral interactions between houseflies and highlight the importance of these factors when designing behavioral experiments using M. domestica....

  20. Locomotion dynamics of hunting in wild cheetahs.

    Science.gov (United States)

    Wilson, A M; Lowe, J C; Roskilly, K; Hudson, P E; Golabek, K A; McNutt, J W

    2013-06-13

    Although the cheetah is recognised as the fastest land animal, little is known about other aspects of its notable athleticism, particularly when hunting in the wild. Here we describe and use a new tracking collar of our own design, containing a combination of Global Positioning System (GPS) and inertial measurement units, to capture the locomotor dynamics and outcome of 367 predominantly hunting runs of five wild cheetahs in Botswana. A remarkable top speed of 25.9 m s(-1) (58 m.p.h. or 93 km h(-1)) was recorded, but most cheetah hunts involved only moderate speeds. We recorded some of the highest measured values for lateral and forward acceleration, deceleration and body-mass-specific power for any terrestrial mammal. To our knowledge, this is the first detailed locomotor information on the hunting dynamics of a large cursorial predator in its natural habitat.

  1. Effect of injection of antisense oligodeoxynucleotides of GAD isozymes into rat ventromedial hypothalamus on food intake and locomotor activity.

    Science.gov (United States)

    Bannai, M; Ichikawa, M; Nishihara, M; Takahashi, M

    1998-02-16

    In the ventromedial hypothalamus (VMH), gamma-aminobutyric acid (GABA) plays a role in regulating feeding and running behaviors. The GABA synthetic enzyme, glutamic acid decarboxylase (GAD), consists of two isozymes, GAD65 and GAD67. In the present study, the phosphorothioated antisense oligodeoxynucleotides (ODNs) of each GAD isozyme were injected bilaterally into the VMH of male rats, and food intake, body weight and locomotor activity were monitored. ODNs were incorporated in the water-absorbent polymer (WAP, 0.2 nmol/microliter) so that ODNs were retained at the injection site. Each antisense ODN of GAD65 or GAD67 tended to reduce food intake on day 1 (day of injection=day 0) though not significantly. An injection combining both antisense ODNs significantly decreased food intake only on day 1, but body weight remained significantly lower than the control for 5 days. This suppression of body weight gain could be attributed to a significant increase in locomotor activity between days 3 and 5. Individual treatment with either ODNs did not change locomotor activity. The increase in daily locomotor activity in the group receiving the combined antisense ODNs occurred mainly during the light phase. Neither vehicle (WAP) nor control ODN affected food intake, body weight and locomotor activity. Histological studies indicated that antisense ODN distributed within 800 micron from the edge of the area where WAP was located 24 h after the injection gradually disappeared within days, but still remained within 300 micron m distance even 7 days after the injection. Antisense ODN was effectively incorporated by all the cell types examined, i.e., neurons, astrocytes and microglias. Further, HPLC analysis revealed that antisense ODNs of GAD isozymes, either alone or combined, decreased the content of GABA by 50% in VMH 24 h after the injection. These results indicate that suppression of GABA synthesis by either of the GAD isozymes is synergistically involved in suppressing food

  2. Evidence for a role of orexin/hypocretin system in vestibular lesion-induced locomotor abnormalities in rats

    Directory of Open Access Journals (Sweden)

    Leilei Pan

    2016-07-01

    Full Text Available Vestibular damage can induce locomotor abnormalities in both animals and humans. Rodents with bilateral vestibular loss showed vestibular deficits syndrome such as circling, opisthotonus as well as locomotor and exploratory hyperactivity. Previous studies have investigated the changes in the dopamine system after vestibular loss, but the results are inconsistent and inconclusive. Numerous evidences indicate that the orexin system is implicated in central motor control. We hypothesized that orexin may be potentially involved in vestibular loss-induced motor disorders. In this study, we examined the effects of arsanilate- or 3, 3′-iminodipropionitrile (IDPN-induced vestibular lesion (AVL or IVL on the orexin-A (OXA labeling in rat hypothalamus using immunohistochemistry. The vestibular lesion-induced locomotor abnormalities were recorded and verified using a histamine H4 receptor antagonist JNJ7777120 (20 mg/kg, i.p.. The effects of the orexin receptor type 1 antagonist SB334867 (16 μg, i.c.v. on these behavior responses were also investigated. At 72 h post-AVL and IVL, animals exhibited vestibular deficit syndrome and locomotor hyperactivity in the home cages. These responses were significantly alleviated by JNJ7777120 which also eliminated AVL-induced increases in exploratory behavior in an open field. The numbers of OXA-labeled neurons in the hypothalamus were significantly increased in the AVL animals at 72 h post-AVL and in the IVL animals at 24, 48 and 72 h post-IVL. SB334867 significantly attenuated the vestibular deficit syndrome and locomotor hyperactivity at 72 h post-AVL and IVL. It also decreased exploratory behavior in the AVL animals. These results suggested that the alteration of OXA expression might contribute to locomotor abnormalities after acute vestibular lesion. The orexin receptors might be the potential therapeutic targets for vestibular disorders.

  3. Locomotor Activity and Body Temperature Patterns over a Temperature Gradient in the Highveld Mole-Rat (Cryptomys hottentotus pretoriae).

    Science.gov (United States)

    Haupt, Meghan; Bennett, Nigel C; Oosthuizen, Maria K

    2017-01-01

    African mole-rats are strictly subterranean mammals that live in extensive burrow systems. High humidity levels in the burrows prevent mole-rats from thermoregulating using evaporative cooling. However, the relatively stable environment of the burrows promotes moderate temperatures and small daily temperature fluctuations. Mole-rats therefore display a relatively wide range of thermoregulation abilities. Some species cannot maintain their body temperatures at a constant level, whereas others employ behavioural thermoregulation. Here we test the effect of ambient temperature on locomotor activity and body temperature, and the relationship between the two parameters, in the highveld mole-rat. We exposed mole-rats to a 12L:12D and a DD light cycle at ambient temperatures of 30°C, 25°C and 20°C while locomotor activity and body temperature were measured simultaneously. In addition, we investigated the endogenous rhythms of locomotor activity and body temperature at different ambient temperatures. Mole-rats displayed nocturnal activity at all three ambient temperatures and were most active at 20°C, but least active at 30°C. Body temperature was highest at 30°C and lowest at 20°C, and the daily cycle was highly correlated with locomotor activity. We show that the mole-rats have endogenous rhythms for both locomotor activity and body temperature. However, the endogenous body temperature rhythm appears to be less robust compared to the locomotor activity rhythm. Female mole-rats appear to be more sensitive to temperature changes than males, increased heterothermy is evident at lower ambient temperatures, whilst males show smaller variation in their body temperatures with changing ambient temperatures. Mole-rats may rely more heavily on behavioural thermoregulation as it is more energy efficient in an already challenging environment.

  4. Locomotor Performance During Rehabilitation of People With Lower Limb Amputation and Prosthetic Nonuse 12 Months After Discharge.

    Science.gov (United States)

    Roffman, Caroline E; Buchanan, John; Allison, Garry T

    2016-07-01

    It is recognized that multifactorial assessments are needed to evaluate balance and locomotor function in people with lower limb amputation. There is no consensus on whether a single screening tool could be used to identify future issues with locomotion or prosthetic use. The purpose of this study was to determine whether different tests of locomotor performance during rehabilitation were associated with significantly greater risk of prosthetic abandonment at 12 months postdischarge. This was a retrospective cohort study. Data for descriptive variables and locomotor tests (ie, 10-Meter Walk Test [10MWT], Timed "Up & Go" Test [TUGT], Six-Minute Walk Test [6MWT], and Four Square Step Test [FSST]) were abstracted from the medical records of 201 consecutive participants with lower limb amputation. Participants were interviewed and classified as prosthetic users or nonusers at 12 months postdischarge. The Mann-Whitney U test was used to analyze whether there were differences in locomotor performance. Receiver operating characteristic curves were generated to determine performance thresholds, and relative risk (RR) was calculated for nonuse. At 12 months postdischarge, 18% (n=36) of the participants had become prosthetic nonusers. Performance thresholds, area under the curve (AUC), and RR of nonuse (95% confidence intervals [CI]) were: for the 10MWT, if walking speed was ≤0.44 ms(-1) (AUC=0.743), RR of nonuse=2.76 (95% CI=1.83, 3.79; PLocomotor performance during rehabilitation may predict future risk of prosthetic nonuse. It may be implied that the 10MWT has the greatest clinical utility as a single screening tool for prosthetic nonuse, given the highest proportion of participants were able to perform this test early in rehabilitation. However, as locomotor skills improve, other tests (in particular, the 6MWT) have specific clinical utility. To fully enable implementation of these locomotor criteria for prosthetic nonuse into clinical practice, validation is warranted

  5. Individual differences in object permanence performance at 8 months: locomotor experience and brain electrical activity.

    Science.gov (United States)

    Bell, M A; Fox, N A

    1997-12-01

    This work was designed to investigate individual differences in hands-and-knees crawling and frontal brain electrical activity with respect to object permanence performance in 76 eight-month-old infants. Four groups of infants (one prelocomotor and 3 with varying lengths of hands-and-knees crawling experience) were tested on an object permanence scale in a research design similar to that used by Kermoian and Campos (1988). In addition, baseline EEG was recorded and used as an indicator of brain development, as in the Bell and Fox (1992) longitudinal study. Individual differences in frontal and occipital EEG power and in locomotor experience were associated with performance on the object permanence task. Infants successful at A-not-B exhibited greater frontal EEG power and greater occipital EEG power than unsuccessful infants. In contrast to Kermoian and Campos (1988), who noted that long-term crawling experience was associated with higher performance on an object permanence scale, infants in this study with any amount of hands and knees crawling experience performed at a higher level on the object permanence scale than prelocomotor infants. There was no interaction among brain electrical activity, locomotor experience, and object permanence performance. These data highlight the value of electrophysiological research and the need for a brain-behavior model of object permanence performance that incorporates both electrophysiological and behavioral factors.

  6. Locomotor inhibition in adults horses faced to stressors: a single postpartum experience may be enough!

    Directory of Open Access Journals (Sweden)

    Virginie eDurier

    2012-10-01

    Full Text Available Despite the number of postpartum handling that a newborn experiences, few studies focus on their long-term consequences. In rats, regular long separations from the mother, during the early life, led to modifications of the locomotor activity when the animal is confronted to a stressor. In horses, one component of the behavioural response to stressful situation is active locomotion. We wondered if the routine postpartum handling undergone by foals, would affect their level of reactivity or the way they express their stress, when older. One single prolonged bout of handling just after birth clearly affected later adult expression of stress reactivity. In social separation associated with novelty, handled and unhandled horses produced an equal amount of whinnies, showing a similar vocal response to stress. However, both groups differed in their locomotor response to the situations. Early-handled foals expressed less of the active forms of locomotion than the control group. Our findings highlight the need of further reflections on long-term effects of routine handlings procedures close to birth.

  7. Activation of the GABAB receptor prevents nicotine-induced locomotor stimulation in mice

    Directory of Open Access Journals (Sweden)

    Carla eLobina

    2011-12-01

    Full Text Available Recent studies demonstrated that activation of the GABAB receptor, either by means of orthosteric agonists or positive allosteric modulators (PAMs, inhibited different nicotine-related behaviors, including intravenous self-administration and conditioned place preference, in rodents. The present study investigated whether the anti-nicotine effects of the GABAB receptor agonist, baclofen, and GABAB PAMs, CGP7930 and GS39783, extend to nicotine stimulant effects. To this end, CD1 mice were initially treated with baclofen (0, 1.25, and 2.5 mg/kg, i.p., CGP7930 (0, 25, and 50 mg/kg, i.g., or GS39783 (0, 25, and 50 mg/kg, i.g., then treated with nicotine (0 and 0.05 mg/kg, s.c., and finally exposed to an automated apparatus for recording of locomotor activity. Pretreatment with doses of baclofen, CGP7930, or GS39783 that did not alter locomotor activity when given with nicotine vehicle fully prevented hyperlocomotion induced by 0.05 mg/kg nicotine. These data extend to nicotine stimulant effects the capacity of baclofen and GABAB PAMs to block the reinforcing, motivational, and rewarding properties of nicotine. These data strengthen the hypothesis that activation of the GABAB receptor may represent a potentially useful, anti-smoking therapeutic strategy.

  8. Effects of Lactuca sativa extract on exploratory behavior pattern, locomotor activity and anxiety in mice

    Directory of Open Access Journals (Sweden)

    S.N. Harsha

    2012-05-01

    Full Text Available Objective: To evaluate antianxiety property of Lactuca sativa, an important and commonly used leafy vegetable known for its medicinal properties belongs to Asteraceae family. Methods: Elevated plus maze (EPM, open field test (OFT, rat exposure test, hyponeophagia and marble burying test were performed in mice models to assess the exploratory behaviour and to assess anxiolytic property of hydro-alcohol extract of Lactuca sativa. Diazepam (1 mg/kg body wt. served as the standard anxiolytic agent for all the tests. The dried extract of the plant leaf in doses of 100, 200 and 400 mg/kg body weight was administered orally to mice for duration of 15 or 30 days and evaluated exploratory behaviour, locomotor and anxiolytic activities. Results: Time spent and number of entries into the open arm was measured in EPM followed by total locomotor activity in OFT and latency to enter the food zone in hyponeophagia. Conclusions: The study suggested that hydro-alcohol extract of Lactuca sativa leaves possess potent anxiolytic property.

  9. Sexual differences in post-hatching Saunders's gulls: size, locomotor activity, and foraging skill.

    Science.gov (United States)

    Yoon, Jongmin; Lee, Seung-Hee; Joo, Eun-Jin; Na, Ki-Jeong; Park, Shi-Ryong

    2013-04-01

    Various selection pressures induce the degree and direction of sexual size dimorphism in animals. Selection favors either larger males for contests over mates or resources, or smaller males are favored for maneuverability; whereas larger females are favored for higher fecundity, or smaller females for earlier maturation for reproduction. In the genus of Larus (seagulls), adult males are generally known to be larger in size than adult females. However, the ontogeny of sexual size dimorphism is not well understood, compared to that in adults. The present study investigates the ontogeny of sexual size dimorphism in Saunders's gulls (Larus saundersi) in captivity. We artificially incubated fresh eggs collected in Incheon, South Korea, and measured body size, locomotor activity, and foraging skill in post-hatching chicks in captivity. Our results indicated that the sexual differences in size and locomotor activity occurred with the post-hatching development. Also, larger males exhibited greater foraging skills for food acquisition than smaller females at 200 days of age. Future studies should assess how the adaptive significance of the sexual size dimorphism in juveniles is linked with sexual divergence in survival rates, intrasexual contests, or parental effort in sexes.

  10. Studies of evolutionary temperature adaptation: muscle function and locomotor performance in Antarctic fish.

    Science.gov (United States)

    Franklin, C E

    1998-09-01

    1. Studies of evolutionary temperature adaptation of muscle and locomotor performance in fish are reviewed with a focus on the Antarctic fauna living at subzero temperatures. 2. Only limited data are available to compare the sustained and burst swimming kinematics and performance of Antarctic, temperate and tropical species. Available data indicate that low temperatures limit maximum swimming performance and this is especially evident in fish larvae. 3. In a recent study, muscle performance in the Antarctic rock cod Notothenia coriiceps at 0 degree C was found to be sufficient to produce maximum velocities during burst swimming that were similar to those seen in the sculpin Myoxocephalus scorpius at 10 degrees C, indicating temperature compensation of muscle and locomotor performance in the Antarctic fish. However, at 15 degrees C, sculpin produce maximum swimming velocities greater than N. coriiceps at 0 degree C. 4. It is recommended that strict hypothesis-driven investigations using ecologically relevant measures of performance are undertaken to study temperature adaptation in Antarctic fish. Recent detailed phylogenetic analyses of the Antarctic fish fauna and their temperate relatives will allow a stronger experimental approach by helping to separate what is due to adaptation to the cold and what is due to phylogeny alone.

  11. Low doses of ivermectin cause sensory and locomotor disorders in dung beetles

    Science.gov (United States)

    Verdú, José R.; Cortez, Vieyle; Ortiz, Antonio J.; González-Rodríguez, Estela; Martinez-Pinna, Juan; Lumaret, Jean-Pierre; Lobo, Jorge M.; Numa, Catherine; Sánchez-Piñero, Francisco

    2015-09-01

    Ivermectin is a veterinary pharmaceutical generally used to control the ecto- and endoparasites of livestock, but its use has resulted in adverse effects on coprophilous insects, causing population decline and biodiversity loss. There is currently no information regarding the direct effects of ivermectin on dung beetle physiology and behaviour. Here, based on electroantennography and spontaneous muscle force tests, we show sub-lethal disorders caused by ivermectin in sensory and locomotor systems of Scarabaeus cicatricosus, a key dung beetle species in Mediterranean ecosystems. Our findings show that ivermectin decreases the olfactory and locomotor capacity of dung beetles, preventing them from performing basic biological activities. These effects are observed at concentrations lower than those usually measured in the dung of treated livestock. Taking into account that ivermectin acts on both glutamate-gated and GABA-gated chloride ion channels of nerve and muscle cells, we predict that ivermectin’s effects at the physiological level could influence many members of the dung pat community. The results indicate that the decline of dung beetle populations could be related to the harmful effects of chemical contamination in the dung.

  12. A simple behavioral test for locomotor function after brain injury in mice.

    Science.gov (United States)

    Tabuse, Masanao; Yaguchi, Masae; Ohta, Shigeki; Kawase, Takeshi; Toda, Masahiro

    2010-11-01

    To establish a simple and reliable test for assessing locomotor function in mice with brain injury, we developed a new method, the rotarod slip test, in which the number of slips of the paralytic hind limb from a rotarod is counted. Brain injuries of different severity were created in adult C57BL/6 mice, by inflicting 1-point, 2-point and 4-point cryo-injuries. These mice were subjected to the rotarod slip test, the accelerating rotarod test and the elevated body swing test (EBST). Histological analyses were performed to assess the severity of the brain damage. Significant and consistent correlations between test scores and severity were observed for the rotarod slip test and the EBST. Only the rotarod slip test detected the mild hindlimb paresis in the acute and sub-acute phase after injury. Our results suggest that the rotarod slip test is the most sensitive and reliable method for assessing locomotor function after brain damage in mice. Copyright © 2010 Elsevier Ltd. All rights reserved.

  13. Sherlock Holmes and the Curious Case of the Human Locomotor Central Pattern Generator.

    Science.gov (United States)

    Klarner, Taryn; Zehr, E Paul

    2018-03-14

    Evidence first described in reduced animal models over 100 years ago led to deductions about the control of locomotion through spinal locomotor central pattern generating (CPG) networks. These discoveries in nature were contemporaneous with another form of deductive reasoning found in popular culture-that of Arthur Conan Doyle's detective "Sherlock Holmes". Since the invasive methods used in reduced non-human animal preparations are not amenable to study in humans, we are left instead with deducing from other measures and observations. Using the deductive reasoning approach of Sherlock Holmes as a metaphor for framing research into human CPGs, we speculate and weigh the evidence that should be observable in humans based on knowledge from other species. This review summarizes indirect inference to assess "observable evidence" of pattern generating activity which leads to the logical deduction of CPG contributions to arm and leg activity during locomotion in humans. The question of where a CPG may be housed in the human nervous system remains incompletely resolved at this time. Ongoing understanding, elaboration and application of functioning locomotor CPGs in humans is important for gait rehabilitation strategies in those with neurological injuries.

  14. Circadian locomotor rhythms in the cricket, Gryllodes sigillatus. II. Interactions between bilaterally paired circadian pacemakers.

    Science.gov (United States)

    Ushirogawa, H; Abe, Y; Tomioka, K

    1997-10-01

    The optic lobe is essential for circadian locomotor rhythms in the cricket, Gryllodes sigillatus. We examined potential interactions between the bilaterally paired optic lobes in circadian rhythm generation. When one optic lobe was removed, the free-running period of the locomotor rhythm slightly but significantly lengthened. When exposed to light-dark cycles (LD) with 26 hr period, intact and sham operated animals were clearly entrained to the light cycle, but a large number of animals receiving unilateral optic nerve severance showed rhythm dissociation. In the dissociation, two rhythmic components appeared; one was readily entrained to the given LD and the other free-ran with a period shorter than 24 hr, and activity was expressed only when they were inphase. The period of the free-running component was significantly longer than that of the animals with a single blinded pacemaker kept in LD13:13, suggesting that the pacemaker on the intact side had some influence on the blinded pacemaker even in the dissociated state. The ratio of animals with rhythm dissociation was greater with the lower light intensity of the LD. The results suggest that the bilaterally distributed pacemakers are only weakly coupled to one another but strongly suppress the activity driven by the partner pacemaker during their subjective day. The strong suppression of activity would be advantageous to keep a stable nocturnality for this cricket living indoors.

  15. Open field locomotor activity and anxiety-related behaviors in mucopolysaccharidosis type IIIA mice.

    Science.gov (United States)

    Lau, Adeline A; Crawley, Allison C; Hopwood, John J; Hemsley, Kim M

    2008-08-05

    Mucopolysaccharidosis (MPS) IIIA, or Sanfilippo syndrome, is a lysosomal storage disorder characterized by severe and progressive neuropathology. Following an asymptomatic period, patients may present with sleep disturbances, cognitive decline, aggressive tendencies and hyperactivity. A naturally-occurring mouse model of MPS IIIA also exhibits many of these behavioral features and has been recently back-crossed onto a C57BL/6 genetic background. To more thoroughly characterize the behavioral phenotype of congenic MPS IIIA mice, we assessed exploratory activity and unconditioned anxiety-related behavior in the elevated plus maze (EPM) and open field locomotor activity. Although MPS IIIA male mice were less active in the EPM at 18 and 20 weeks of age, they were more likely to explore the open arms than their normal counter-parts suggesting reduced anxiety. Repeated EPM testing reduced exploration of the open arms in MPS IIIA mice. In the open field test, significant reductions in activity were evident in naïve-tested male MPS IIIA mice from 10 weeks of age. Female normal and MPS IIIA mice displayed similar exploratory activity in the open field test. These differences in anxiety and locomotor activity will allow us to evaluate the efficacy of therapeutic regimes for MPS IIIA as a forerunner to developing safe and effective therapies for Sanfilippo patients.

  16. Spinal cord injury: overview of experimental approaches used to restore locomotor activity.

    Science.gov (United States)

    Fakhoury, Marc

    2015-01-01

    Spinal cord injury affects more than 2.5 million people worldwide and can lead to paraplegia and quadriplegia. Anatomical discontinuity in the spinal cord results in disruption of the impulse conduction that causes temporary or permanent changes in the cord's normal functions. Although axonal regeneration is limited, damage to the spinal cord is often accompanied by spontaneous plasticity and axon regeneration that help improve sensory and motor skills. The recovery process depends mainly on synaptic plasticity in the preexisting circuits and on the formation of new pathways through collateral sprouting into neighboring denervated territories. However, spontaneous recovery after spinal cord injury can go on for several years, and the degree of recovery is very limited. Therefore, the development of new approaches that could accelerate the gain of motor function is of high priority to patients with damaged spinal cord. Although there are no fully restorative treatments for spinal injury, various rehabilitative approaches have been tested in animal models and have reached clinical trials. In this paper, a closer look will be given at the potential therapies that could facilitate axonal regeneration and improve locomotor recovery after injury to the spinal cord. This article highlights the application of several interventions including locomotor training, molecular and cellular treatments, and spinal cord stimulation in the field of rehabilitation research. Studies investigating therapeutic approaches in both animal models and individuals with injured spinal cords will be presented.

  17. Trace Amine-Associated Receptor 1 Modulates the Locomotor and Sensitization Effects of Nicotine

    Science.gov (United States)

    Sukhanov, Ilya; Dorofeikova, Mariia; Dolgorukova, Antonina; Dorotenko, Artem; Gainetdinov, Raul R.

    2018-01-01

    Trace amine-associated receptor 1 (TAAR1) has emerged as a promising target for addiction treatments because it affects dopamine transmission in the mesolimbic pathway. TAAR1 is involved in the effects of addictive drugs, such as amphetamines, cocaine and ethanol, but the impact of TAAR1 on the effects of nicotine, the psychoactive drug responsible for the development and maintenance of tobacco smoking, has not yet been studied. This study was performed to investigate the possible modulatory action of TAAR1 on the effects of nicotine on locomotor behaviors in rats and mice. Pretreatment with the TAAR1 agonist RO5263397 dose-dependently decreased nicotine-induced hyperlocomotion in rats habituated to locomotor boxes, prevented the development of nicotine sensitization and blocked hypermotility in nicotine-sensitized rats at the highest tested dose (10 mg/kg). The lack of TAAR1 failed to affect the effects of nicotine on the locomotion of mutant mice. Based on the results of the present study, TAAR1 activation attenuates the locomotion-stimulating effects of nicotine on rats. These results further support the previously proposed hypothesis that TAAR1 is a promising target for the prevention and treatment of drug addiction. Further studies aimed at analyzing the effects of TAAR1 agonists on animal models of nicotine addiction are warranted. PMID:29681856

  18. Trace Amine-Associated Receptor 1 Modulates the Locomotor and Sensitization Effects of Nicotine

    Directory of Open Access Journals (Sweden)

    Ilya Sukhanov

    2018-04-01

    Full Text Available Trace amine-associated receptor 1 (TAAR1 has emerged as a promising target for addiction treatments because it affects dopamine transmission in the mesolimbic pathway. TAAR1 is involved in the effects of addictive drugs, such as amphetamines, cocaine and ethanol, but the impact of TAAR1 on the effects of nicotine, the psychoactive drug responsible for the development and maintenance of tobacco smoking, has not yet been studied. This study was performed to investigate the possible modulatory action of TAAR1 on the effects of nicotine on locomotor behaviors in rats and mice. Pretreatment with the TAAR1 agonist RO5263397 dose-dependently decreased nicotine-induced hyperlocomotion in rats habituated to locomotor boxes, prevented the development of nicotine sensitization and blocked hypermotility in nicotine-sensitized rats at the highest tested dose (10 mg/kg. The lack of TAAR1 failed to affect the effects of nicotine on the locomotion of mutant mice. Based on the results of the present study, TAAR1 activation attenuates the locomotion-stimulating effects of nicotine on rats. These results further support the previously proposed hypothesis that TAAR1 is a promising target for the prevention and treatment of drug addiction. Further studies aimed at analyzing the effects of TAAR1 agonists on animal models of nicotine addiction are warranted.

  19. Mice Lacking EGR1 Have Impaired Clock Gene (BMAL1) Oscillation, Locomotor Activity, and Body Temperature.

    Science.gov (United States)

    Riedel, Casper Schwartz; Georg, Birgitte; Jørgensen, Henrik L; Hannibal, Jens; Fahrenkrug, Jan

    2018-01-01

    Early growth response transcription factor 1 (EGR1) is expressed in the suprachiasmatic nucleus (SCN) after light stimulation. We used EGR1-deficient mice to address the role of EGR1 in the clock function and light-induced resetting of the clock. The diurnal rhythms of expression of the clock genes BMAL1 and PER1 in the SCN were evaluated by semi-quantitative in situ hybridization. We found no difference in the expression of PER1 mRNA between wildtype and EGR1-deficient mice; however, the daily rhythm of BMAL1 mRNA was completely abolished in the EGR1-deficient mice. In addition, we evaluated the circadian running wheel activity, telemetric locomotor activity, and core body temperature of the mice. Loss of EGR1 neither altered light-induced phase shifts at subjective night nor affected negative masking. Overall, circadian light entrainment was found in EGR1-deficient mice but they displayed a reduced locomotor activity and an altered temperature regulation compared to wild type mice. When placed in running wheels, a subpopulation of EGR1-deficient mice displayed a more disrupted activity rhythm with no measurable endogenous period length (tau). In conclusion, the present study provides the first evidence that the circadian clock in the SCN is disturbed in mice deficient of EGR1.

  20. Regulation by orexin of feeding behaviour and locomotor activity in the goldfish.

    Science.gov (United States)

    Nakamachi, T; Matsuda, K; Maruyama, K; Miura, T; Uchiyama, M; Funahashi, H; Sakurai, T; Shioda, S

    2006-04-01

    Orexin is a hypothalamic neuropeptide that is implicated in the regulation of feeding behaviour and the sleep-wakefulness cycle in mammals. However, in spite of a growing body of knowledge concerning orexin in mammals, the orexin system and its function have not been well studied in lower vertebrates. In the present study, we first examined the effect of feeding status on the orexin-like immunoreactivity (orexin-LI) and the expression of orexin mRNA in the goldfish brain. The number of cells showing orexin-LI in the hypothalamus of goldfish brain showed a significant increase in fasted fish and a significant decrease in glucose-injected fish. The expression level of orexin mRNA in the brains of fasted fish increased compared to that of fed fish. We also examined the effect of an i.c.v. injection of orexin or an anti-orexin serum on food intake and locomotor activity in the goldfish. Administration of orexin by i.c.v. injection induced a significant increase of food intake and locomotor activity, whereas i.p. injection of glucose or i.c.v. injection of anti-orexin serum decreased food consumption. These results indicate that the orexin functions as an orexigenic factor in the goldfish brain.

  1. Muscle fiber type distribution in climbing Hawaiian gobioid fishes: ontogeny and correlations with locomotor performance.

    Science.gov (United States)

    Cediel, Roberto A; Blob, Richard W; Schrank, Gordon D; Plourde, Robert C; Schoenfuss, Heiko L

    2008-01-01

    Three species of Hawaiian amphidromous gobioid fishes are remarkable in their ability to climb waterfalls up to several hundred meters tall. Juvenile Lentipes concolor and Awaous guamensis climb using rapid bursts of axial undulation, whereas juvenile Sicyopterus stimpsoni climb using much slower movements, alternately attaching oral and pelvic sucking disks to the substrate during prolonged bouts of several cycles. Based on these differing climbing styles, we hypothesized that propulsive musculature in juvenile L. concolor and A. guamensis would be dominated by white muscle fibers, whereas S. stimpsoni would exhibit a greater proportion of red muscle fibers than other climbing species. We further predicted that, because adults of these species shift from climbing to burst swimming as their main locomotor behavior, muscle from adult fish of all three species would be dominated by white fibers. To test these hypotheses, we used ATPase assays to evaluate muscle fiber type distribution in Hawaiian climbing gobies for three anatomical regions (midbody, anal, and tail). Axial musculature was dominated by white muscle fibers in juveniles of all three species, but juvenile S. stimpsoni had a significantly greater proportion of red fibers than the other two species. Fiber type proportions of adult fishes did not differ significantly from those of juveniles. Thus, muscle fiber type proportions in juveniles appear to help accommodate differences in locomotor demands among these species, indicating that they overcome the common challenge of waterfall climbing through both diverse behaviors and physiological specializations.

  2. Technological Capability and Firm Performance

    Directory of Open Access Journals (Sweden)

    Fernanda Maciel Reichert

    2014-08-01

    Full Text Available This research aims to investigate the relationship between investments in technological capability and economic performance in Brazilian firms. Based on economic development theory and on developed countries history, it is assumed that this relationship is positive. Through key indicators, 133 Brazilian firms have been analyzed. Given the economic circumstances of an emerging economy, which the majority of businesses are primarily based on low and medium-low-technology industries, it is not possible to affirm the existence of a positive relation between technological capability and firm performance. There are other elements that allow firms to achieve such results. Firms of lower technological intensity industries performed above average in the economic performance indicators, adversely, they invested below average in technological capability. These findings do not diminish the merit of firms’ and country’s success. They in fact confirm a historical tradition of a country that concentrates its efforts on basic industries.

  3. Functional capability of piping systems

    International Nuclear Information System (INIS)

    Terao, D.; Rodabaugh, E.C.

    1992-11-01

    General Design Criterion I of Appendix A to Part 50 of Title 10 of the Code of Federal Regulations requires, in part, that structures, systems, and components important to safety be designed to withstand the effects of earthquakes without a loss of capability to perform their safety function. ne function of a piping system is to convey fluids from one location to another. The functional capability of a piping system might be lost if, for example, the cross-sectional flow area of the pipe were deformed to such an extent that the required flow through the pipe would be restricted. The objective of this report is to examine the present rules in the American Society of Mechanical Engineers Boiler and Pressure Vessel Code, Section III, and potential changes to these rules, to determine if they are adequate for ensuring the functional capability of safety-related piping systems in nuclear power plants

  4. Upgrading of TREAT experimental capabilities

    International Nuclear Information System (INIS)

    Dickerman, C.E.; Rose, D.; Bhattacharyya, S.K.

    1982-01-01

    The TREAT facility at the Argonne National Laboratory site in the Idaho National Engineering Laboratory is being upgraded to provide capabilities for fast-reactor-safety transient experiments not possible at any other experimental facility. Principal TREAT Upgrade (TU) goal is provision for 37-pin size experiments on energetics of core-disruptive accidents (CDA) in fast breeder reactor cores with moderate sodium void coefficients. this goal requires a significant enhancement of the capabilities of the TREAT facility, specifically including reactor control, hardened neutron spectrum incident on the test sample, and enlarged building. The upgraded facility will retain the capability for small-size experiments of the types currently being performed in TREAT. Reactor building and crane upgrading have been completed. TU schedules call for the components of the upgraded reactor system to be finished in 1984, including upgraded TREAT fuel and control system, and expanded coverage by the hodoscope fuel-motion diagnostics system

  5. Ensuring US National Aeronautics Test Capabilities

    Science.gov (United States)

    Marshall, Timothy J.

    2010-01-01

    U.S. leadership in aeronautics depends on ready access to technologically advanced, efficient, and affordable aeronautics test capabilities. These systems include major wind tunnels and propulsion test facilities and flight test capabilities. The federal government owns the majority of the major aeronautics test capabilities in the United States, primarily through the National Aeronautics and Space Administration (NASA) and the Department of Defense (DoD). However, changes in the Aerospace landscape, primarily the decrease in demand for testing over the last 20 years required an overarching strategy for management of these national assets. Therefore, NASA established the Aeronautics Test Program (ATP) as a two-pronged strategic initiative to: (1) retain and invest in NASA aeronautics test capabilities considered strategically important to the agency and the nation, and (2) establish a strong, high level partnership with the DoD. Test facility utilization is a critical factor for ATP because it relies on user occupancy fees to recover a substantial part of the operations costs for its facilities. Decreasing utilization is an indicator of excess capacity and in some cases low-risk redundancy (i.e., several facilities with basically the same capability and overall low utilization). However, low utilization does not necessarily translate to lack of strategic importance. Some facilities with relatively low utilization are nonetheless vitally important because of the unique nature of the capability and the foreseeable aeronautics testing needs. Unfortunately, since its inception, the customer base for ATP has continued to shrink. Utilization of ATP wind tunnels has declined by more than 50% from the FY 2006 levels. This significant decrease in customer usage is attributable to several factors, including the overall decline in new programs and projects in the aerospace sector; the impact of computational fluid dynamics (CFD) on the design, development, and research

  6. Design Management Capability and Product Innovation in SMEs

    OpenAIRE

    Fernández-Mesa, Ana Isabel; ALEGRE VIDAL, JOAQUIN; CHIVA GOMEZ, RICARDO; Gutiérrez Gracia, Antonio

    2013-01-01

    [EN] Purpose The aim of this paper is to present design management as a dynamic capability and to analyze its mediating role between organizational learning capability and product innovation performance in small and medium enterprises (SMEs). Design/methodology/approach Structural equation modeling is used to test the research hypotheses based on data from the Italian and Spanish ceramic tile industries. The data are derived from the responses of 182 companies (50 percent of the targ...

  7. Are Hydrostatic Models Still Capable of Simulating Oceanic Fronts

    Science.gov (United States)

    2016-11-10

    Hydrostatic Models Still Capable of Simulating Oceanic Fronts Yalin Fan Zhitao Yu Ocean Dynamics and Prediction Branch Oceanography Division FengYan Shi...OF PAGES 17. LIMITATION OF ABSTRACT Are Hydrostatic Models Still Capable of Simulating Oceanic Fronts? Yalin Fan, Zhitao Yu, and, Fengyan Shi1 Naval...mixed layer and thermocline simulations as well as large scale circulations. Numerical experiments are conducted using hydrostatic (HY) and

  8. Nanofabrication principles, capabilities and limits

    CERN Document Server

    Cui, Zheng

    2017-01-01

    This second edition of Nanofabrication is one of the most comprehensive introductions on nanofabrication technologies and processes. A practical guide and reference, this book introduces readers to all of the developed technologies that are capable of making structures below 100nm. The principle of each technology is introduced and illustrated with minimum mathematics involved. Also analyzed are the capabilities of each technology in making sub-100nm structures, and the limits of preventing a technology from going further down the dimensional scale. This book provides readers with a toolkit that will help with any of their nanofabrication challenges.

  9. Judgmental Forecasting of Operational Capabilities

    DEFF Research Database (Denmark)

    Hallin, Carina Antonia; Tveterås, Sigbjørn; Andersen, Torben Juul

    This paper explores a new judgmental forecasting indicator, the Employee Sensed Operational Capabilities (ESOC). The purpose of the ESOC is to establish a practical prediction tool that can provide early signals about changes in financial performance by gauging frontline employees’ sensing...... of changes in the firm’s operational capabilities. We present the first stage of the development of ESOC by applying a formative measurement approach to test the index in relation to financial performance and against an organizational commitment scale. We use distributed lag models to test whether the ESOC...

  10. Elevated copper levels during larval development cause altered locomotor behavior in the adult carabid beetle Pterostichus cupreus L. (Coleoptera: Carbidae)

    DEFF Research Database (Denmark)

    Bayley, M; Baatrup, E; Heimbach, U

    1995-01-01

    It is generally believed that copper causes changes in carabid communities indirectly by reducing food availability, because these animals are frequently found to have only slightly elevated metal contents even close to pollution sources. Using computer-centered video tracking, the locomotor......, but not to effect the emergence weights of adults of either sex. This toxic effect on the larvae was preserved through pupation to the surviving adults, which were normal in size and appearance, but displayed a dramatically depressed locomotor behavior. Copper analysis of these adults revealed that copper levels...

  11. Temporal phasing of locomotor activity, heart rate rhythmicity, and core body temperature is disrupted in VIP receptor 2-deficient mice

    DEFF Research Database (Denmark)

    Hannibal, Jens; Hsiung, Hansen M; Fahrenkrug, Jan

    2011-01-01

    these observations with observations made from mice examined by wheel-running activity. The study demonstrates that VPAC2 signaling is necessary for a functional circadian clock driving locomotor activity, core body temperature, and heart rate rhythmicity, since VPAC2-deficient mice lose the rhythms in all three...... to that of wild-type mice. The use of telemetric devices to measure circadian locomotor activity, temperature, and heart rate, together with the classical determination of circadian rhythms of wheel-running activity, raises questions about how representative wheel-running activity may be of other behavioral...

  12. Injury scores and locomotor disorders of Holstein cows in a free-stall facility with different beds

    OpenAIRE

    Cecchin, Daiane; Universidade Federal de Lavras - UFLA Lavras - MG; Campos, Alessandro Torres; Universidade Federal de Lavras - UFLA Lavras - MG; Pires, Maria de Fátima Ávila; Sousa, Francine Aparecida; Universidade Federal de Lavras - UFLA Lavras - MG; Amaral, Pedro Ivo Sodré; Universidade Federal de Lavras - UFLA Lavras - MG; Yanagi Junior, Tadayuki; Universidade Federal de Lavras - UFLA Lavras - MG; Ferreira, Suane Alves; Médica Veterinária – UNIPAC Juiz de Fora, MG.; Souza, Myriam Cristiane Morais; Graduanda em Medicina Veterinária – UNIPAC Juiz de Fora, MG.; Cecchin, Diego; Especialista em Gestão – UPF, Passo Fundo, RS

    2015-01-01

    The aim of the present study was to evaluate hock and knee injuries and locomotor disorders in 36 multiparous Holstein cows confined in a free-stall model system with two types of beds at Embrapa Dairy Cattle in the city of Coronel Pacheco / MG. Rubber composite beds and sand beds were compared and the hock and knee injuries and locomotor disorders were assessed for severity scores. There was no difference between the scores or hock lesions observed at the beginning and end of the trial perio...

  13. Effects of scallop shell extract on scopolamine-induced memory impairment and MK801-induced locomotor activity

    OpenAIRE

    HASEGAWA, Yasushi; INOUE, Tatsuro; KAWAMINAMI, Satoshi; FUJITA, Miho

    2016-01-01

    ObjectiveTo evaluate the neuroprotective effects of the organic components of scallop shells (scallop shell extract) on memory impairment and locomotor activity induced by scopolamine or 5-methyl-10,11-dihydro-5H-dibenzo (a,d) cyclohepten-5,10-imine (MK801).MethodsEffect of the scallop shell extract on memory impairment and locomotor activity was investigated using the Y-maze test, the Morris water maze test, and the open field test.ResultsScallop shell extract significantly reduced scopolami...

  14. Differences in the locomotor-activating effects of indirect serotonin agonists in habituated and non-habituated rats.

    Science.gov (United States)

    Halberstadt, Adam L; Buell, Mahálah R; Price, Diana L; Geyer, Mark A

    2012-07-01

    The indirect serotonin (5-HT) agonist 3,4-methylenedioxymethamphetamine (MDMA) produces a distinct behavioral profile in rats consisting of locomotor hyperactivity, thigmotaxis, and decreased exploration. The indirect 5-HT agonist α-ethyltryptamine (AET) produces a similar behavioral profile. Using the Behavioral Pattern Monitor (BPM), the present investigation examined whether the effects of MDMA and AET are dependent on the novelty of the testing environment. These experiments were conducted in Sprague-Dawley rats housed on a reversed light cycle and tested during the dark phase of the light/dark cycle. We found that racemic MDMA (RS-MDMA; 3 mg/kg, SC) increased locomotor activity in rats tested in novel BPM chambers, but had no effect on locomotor activity in rats habituated to the BPM chambers immediately prior to testing. Likewise, AET (5 mg/kg, SC) increased locomotor activity in non-habituated animals but not in animals habituated to the test chambers. These results were unexpected because previous reports indicate that MDMA has robust locomotor-activating effects in habituated animals. To further examine the influence of habituation on MDMA-induced locomotor activity, we conducted parametric studies with S-(+)-MDMA (the more active enantiomer) in habituated and non-habituated rats housed on a standard or reversed light cycle. Light cycle was included as a variable due to reported differences in sensitivity to serotonergic ligands during the dark and light phases. In confirmation of our initial studies, rats tested during the dark phase and habituated to the BPM did not show an S-(+)-MDMA (3 mg/kg, SC)-induced increase in locomotor activity, whereas non-habituated rats did. By contrast, in rats tested during the light phase, S-(+)-MDMA increased locomotor activity in both non-habituated and habituated rats, although the response in habituated animals was attenuated. The finding that habituation and light cycle interact to influence MDMA- and AET

  15. Effects of Resveratrol on Daily Rhythms of Locomotor Activity and Body Temperature in Young and Aged Grey Mouse Lemurs

    Directory of Open Access Journals (Sweden)

    Fabien Pifferi

    2013-01-01

    Full Text Available In several species, resveratrol, a polyphenolic compound, activates sirtuin proteins implicated in the regulation of energy balance and biological clock processes. To demonstrate the effect of resveratrol on clock function in an aged primate, young and aged mouse lemurs (Microcebus murinus were studied over a 4-week dietary supplementation with resveratrol. Spontaneous locomotor activity and daily variations in body temperature were continuously recorded. Reduction in locomotor activity onset and changes in body temperature rhythm in resveratrol-supplemented aged animals suggest an improved synchronisation on the light-dark cycle. Resveratrol could be a good candidate to restore the circadian rhythms in the elderly.

  16. Methodical aspects of radionuclide study of locomotor system in patients with systemic diseases of connective tissue with single photon emission computed tomography

    International Nuclear Information System (INIS)

    Potsibyina, V.V.; Oderyij, Je.A.

    1998-01-01

    The original technique was used to examine 427 patients aged 18-64 with systemic diseases of locomotor system connective tissue and 65 controls. In addition to clinical studies, radionuclide signs of locomotor system lesions was investigated with NUCLETRON APEX SP-6 CT unit using labeled with Tc-99m and osteotropic radiopharmaceuticals

  17. Building server capabilities in China

    DEFF Research Database (Denmark)

    Adeyemi, Oluseyi; Slepniov, Dmitrij; Wæhrens, Brian Vejrum

    2012-01-01

    The purpose of this paper is to further our understanding of multinational companies building server capabilities in China. The paper is based on the cases of two western companies with operations in China. The findings highlight a number of common patterns in the 1) managerial challenges related...

  18. Microfoundations of Routines and Capabilities

    DEFF Research Database (Denmark)

    Felin, Teppo; Foss, Nicolai Juul; Heimriks, Koen H.

    We discuss the microfoundations of routines and capabilities, including why a microfoundations view is needed and how it may inform work on organizational and competitive heterogeneity. Building on extant research, we identify three primary categories of micro-level components underlying routines...

  19. Microfoundations of Routines and Capabilities

    DEFF Research Database (Denmark)

    Felin, Tippo; Foss, Nicolai Juul; Heimericks, Koen H.

    2012-01-01

    This article introduces the Special Issue and discusses the microfoundations of routines and capabilities, including why a microfoundations view is needed and how it may inform work on organizational and competitive heterogeneity. Building on extant research, we identify three primary categories ...

  20. Capability and Learning to Choose

    Science.gov (United States)

    LeBmann, Ortrud

    2009-01-01

    The Capability Approach (henceforth CA) is in the first place an approach to the evaluation of individual well-being and social welfare. Many disciplines refer to the CA, first and foremost welfare economics, development studies and political philosophy. Educational theory was not among the first disciplines that took notice of the CA, but has a…