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Sample records for self-optimization community stability

  1. Optimism and self-esteem are related to sleep. Results from a large community-based sample.

    Science.gov (United States)

    Lemola, Sakari; Räikkönen, Katri; Gomez, Veronica; Allemand, Mathias

    2013-12-01

    There is evidence that positive personality characteristics, such as optimism and self-esteem, are important for health. Less is known about possible determinants of positive personality characteristics. To test the relationship of optimism and self-esteem with insomnia symptoms and sleep duration. Sleep parameters, optimism, and self-esteem were assessed by self-report in a community-based sample of 1,805 adults aged between 30 and 84 years in the USA. Moderation of the relation between sleep and positive characteristics by gender and age as well as potential confounding of the association by depressive disorder was tested. Individuals with insomnia symptoms scored lower on optimism and self-esteem largely independent of age and sex, controlling for symptoms of depression and sleep duration. Short sleep duration (self-esteem when compared to individuals sleeping 7-8 h, controlling depressive symptoms. Long sleep duration (>9 h) was also related to low optimism and self-esteem independent of age and sex. Good and sufficient sleep is associated with positive personality characteristics. This relationship is independent of the association between poor sleep and depression.

  2. Frequency, stability and differentiation of self-reported school fear and truancy in a community sample

    OpenAIRE

    Steinhausen, Hans-Christoph; Müller, Nora; Metzke, Christa Winkler

    2008-01-01

    Abstract Background Surprisingly little is known about the frequency, stability, and correlates of school fear and truancy based on self-reported data of adolescents. Methods Self-reported school fear and truancy were studied in a total of N = 834 subjects of the community-based Zurich Adolescent Psychology and Psychopathology Study (ZAPPS) at two times with an average age of thirteen and sixteen years. Group definitions were based on two behavioural items of the Youth Self-Report (YSR). Comp...

  3. Frequency, stability and differentiation of self-reported school fear and truancy in a community sample

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    Metzke Christa

    2008-07-01

    Full Text Available Abstract Background Surprisingly little is known about the frequency, stability, and correlates of school fear and truancy based on self-reported data of adolescents. Methods Self-reported school fear and truancy were studied in a total of N = 834 subjects of the community-based Zurich Adolescent Psychology and Psychopathology Study (ZAPPS at two times with an average age of thirteen and sixteen years. Group definitions were based on two behavioural items of the Youth Self-Report (YSR. Comparisons included a control group without indicators of school fear or truancy. The three groups were compared across questionnaires measuring emotional and behavioural problems, life-events, self-related cognitions, perceived parental behaviour, and perceived school environment. Results The frequency of self-reported school fear decreased over time (6.9 vs. 3.6% whereas there was an increase in truancy (5.0 vs. 18.4%. Subjects with school fear displayed a pattern of associated internalizing problems and truants were characterized by associated delinquent behaviour. Among other associated psychosocial features, the distress coming from the perceived school environment in students with school fear is most noteworthy. Conclusion These findings from a community study show that school fear and truancy are frequent and display different developmental trajectories. Furthermore, previous results are corroborated which are based on smaller and selected clinical samples indicating that the two groups display distinct types of school-related behaviour.

  4. Evaluation of primary stability of self-tapping and non-self-tapping dental implants. A 12-week clinical study.

    Science.gov (United States)

    Marković, Aleksa; Calvo-Guirado, José Luís; Lazić, Zoran; Gómez-Moreno, Gerardo; Ćalasan, Dejan; Guardia, Javier; Čolic, Snježana; Aguilar-Salvatierra, Antonio; Gačić, Bojan; Delgado-Ruiz, Rafael; Janjić, Bojan; Mišić, Tijana

    2013-06-01

    The aim of this study was to investigate the relationship between surgical techniques and implant macro-design (self-tapping/non-self-tapping) for the optimization of implant stability in the low-density bone present in the posterior maxilla using resonance frequency analysis (RFA). A total of 102 implants were studied. Fifty-six self-tapping BlueSkyBredent® (Bredent GmbH&Co.Kg®, Senden, Germany) and 56 non-self-tapping Standard Plus Straumann® (Institut Straumann AG®, Waldenburg, Switzerland) were placed in the posterior segment of the maxilla. Implants of both types were placed in sites prepared with either lateral bone-condensing or with bone-drilling techniques. Implant stability measurements were performed using RFA immediately after implant placement and weekly during a 12-week follow-up period. Both types of implants placed after bone condensing achieved significantly higher stability immediately after surgery, as well as during the entire 12-week observation period compared with those placed following bone drilling. After bone condensation, there were no significant differences in primary stability or in implant stability after the first week between both implant types. From 2 to 12 postoperative weeks, significantly higher stability was shown by self-tapping implants. After bone drilling, self-tapping implants achieved significantly higher stability than non-self-tapping implants during the entire follow-up period. The outcomes of the present study indicate that bone drilling is not an effective technique for improving implant stability and, following this technique, the use of self-tapping implants is highly recommended. Implant stability optimization in the soft bone can be achieved by lateral bone-condensing technique, regardless of implant macro-design. © 2011 Wiley Periodicals, Inc.

  5. The Self-esteem Stability Scale (SESS) for Cross-Sectional Direct Assessment of Self-esteem Stability

    OpenAIRE

    Tobias Altmann; Marcus Roth

    2018-01-01

    Self-esteem stability describes fluctuations in the level of self-esteem experienced by individuals over a brief period of time. In recent decades, self-esteem stability has repeatedly been shown to be an important variable affecting psychological functioning. However, measures of self-esteem stability are few and lacking in validity. In this paper, we present the Self-Esteem Stability Scale (SESS), a unidimensional and very brief scale to directly assess self-esteem stability. In four studie...

  6. The Self-esteem Stability Scale (SESS) for Cross-Sectional Direct Assessment of Self-esteem Stability.

    Science.gov (United States)

    Altmann, Tobias; Roth, Marcus

    2018-01-01

    Self-esteem stability describes fluctuations in the level of self-esteem experienced by individuals over a brief period of time. In recent decades, self-esteem stability has repeatedly been shown to be an important variable affecting psychological functioning. However, measures of self-esteem stability are few and lacking in validity. In this paper, we present the Self-Esteem Stability Scale (SESS), a unidimensional and very brief scale to directly assess self-esteem stability. In four studies (total N = 826), we describe the development of the SESS and present evidence for its validity with respect to individual outcomes (life satisfaction, neuroticism, and vulnerable narcissism) and dyadic outcomes (relationship satisfaction in self- and partner ratings) through direct comparisons with existing measures. The new SESS proved to be a stronger predictor than the existing scales and had incremental validity over and above self-esteem level. The results also showed that all cross-sectional measures of self-esteem stability were only moderately associated with variability in self-esteem levels assessed longitudinally with multiple administrations of the Rosenberg Self-Esteem Scale. We discuss this validity issue, arguing that direct and indirect assessment approaches measure relevant, yet different aspects of self-esteem stability.

  7. The Self-esteem Stability Scale (SESS) for Cross-Sectional Direct Assessment of Self-esteem Stability

    Science.gov (United States)

    Altmann, Tobias; Roth, Marcus

    2018-01-01

    Self-esteem stability describes fluctuations in the level of self-esteem experienced by individuals over a brief period of time. In recent decades, self-esteem stability has repeatedly been shown to be an important variable affecting psychological functioning. However, measures of self-esteem stability are few and lacking in validity. In this paper, we present the Self-Esteem Stability Scale (SESS), a unidimensional and very brief scale to directly assess self-esteem stability. In four studies (total N = 826), we describe the development of the SESS and present evidence for its validity with respect to individual outcomes (life satisfaction, neuroticism, and vulnerable narcissism) and dyadic outcomes (relationship satisfaction in self- and partner ratings) through direct comparisons with existing measures. The new SESS proved to be a stronger predictor than the existing scales and had incremental validity over and above self-esteem level. The results also showed that all cross-sectional measures of self-esteem stability were only moderately associated with variability in self-esteem levels assessed longitudinally with multiple administrations of the Rosenberg Self-Esteem Scale. We discuss this validity issue, arguing that direct and indirect assessment approaches measure relevant, yet different aspects of self-esteem stability. PMID:29487551

  8. The Self-esteem Stability Scale (SESS for Cross-Sectional Direct Assessment of Self-esteem Stability

    Directory of Open Access Journals (Sweden)

    Tobias Altmann

    2018-02-01

    Full Text Available Self-esteem stability describes fluctuations in the level of self-esteem experienced by individuals over a brief period of time. In recent decades, self-esteem stability has repeatedly been shown to be an important variable affecting psychological functioning. However, measures of self-esteem stability are few and lacking in validity. In this paper, we present the Self-Esteem Stability Scale (SESS, a unidimensional and very brief scale to directly assess self-esteem stability. In four studies (total N = 826, we describe the development of the SESS and present evidence for its validity with respect to individual outcomes (life satisfaction, neuroticism, and vulnerable narcissism and dyadic outcomes (relationship satisfaction in self- and partner ratings through direct comparisons with existing measures. The new SESS proved to be a stronger predictor than the existing scales and had incremental validity over and above self-esteem level. The results also showed that all cross-sectional measures of self-esteem stability were only moderately associated with variability in self-esteem levels assessed longitudinally with multiple administrations of the Rosenberg Self-Esteem Scale. We discuss this validity issue, arguing that direct and indirect assessment approaches measure relevant, yet different aspects of self-esteem stability.

  9. Design and optimization of self-nanoemulsifying formulations for lipophilic drugs

    International Nuclear Information System (INIS)

    Zhao, Tianjing; Maniglio, Devid; Motta, Antonella; Migliaresi, Claudio; Chen, Jie; Chen, Bin

    2015-01-01

    The purpose of the current study was to develop and optimize novel self-nanoemulsifying drug delivery systems (SNEDDS) with a high proportion of essential oil as carriers for lipophilic drugs. Solubility and droplet size as a function of the composition were investigated, and a ternary phase diagram was constructed in order to identify the self-emulsification regions. The optimized SNEDDS formulation consisted of lemon essential oil (oil), Cremophor RH40 (surfactant) and Transcutol HP (co-surfactant) in the ratio 50:30:20 (v/v). Ibuprofen was chosen as the model drug. The droplet size, ζ-potential and stability of the drug-loaded optimized formulations were determined. The stability of SNEDDS was proved after triple freezing/thawing cycles and storage at 4 °C and 25 °C for 3 months. In vitro drug release studies of optimized SNEDDS revealed a significant increase of the drug release and release rate in comparison to the Ibuprofen suspension (80% versus approximately 40% in 2 h). The results indicated that these SNEDDS formulations could be used to improve the bioavailability of lipophilic drugs. (paper)

  10. SPECIES DIVERSITY AND STABILITY OF BIRD COMMUNITIES

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    Matsyura M.V.

    2011-12-01

    Full Text Available When comparing the suggested stability indicators, we obtained statistically significant correlations for indicators of annual stability of species and total number and standard deviation of the logarithm of the number. Annual Stability Index can be applied with a high degree of reliability as a characteristic of the averaged structure of the community and its pyramid of abundances. The results of correlation analysis confirm our assumptions about the correlation between stability over the years and indices of species diversity and relative uniformity.The final task of the study was to create a mathematical model of stability, where the independent variables are the indices of species diversity. The calculation of these indices allows forecasting birds’ community stability. According to the result of multiple regression for the indicators of diversity and stability of the breeding birds’ community highest correlation coefficients were obtained fro Shannon index and Simpson's dominance Index.Community stability could be determined by its overall species diversity. When considering the stability of community its diversity should be considered as a combination of uniformity of their total number and number of species. The most suitable predictors for the community stability were the nonparametric index of dominance and information-statistical indices, since they considered simultaneously evenness and richness. The community stability is subject of the complexity of its internal communications pattern.

  11. OPTIMAL CONTROL FOR ELECTRIC VEHICLE STABILIZATION

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    MARIAN GAICEANU

    2016-01-01

    Full Text Available This main objective of the paper is to stabilize an electric vehicle in optimal manner to a step lane change maneuver. To define the mathematical model of the vehicle, the rigid body moving on a plane is taken into account. An optimal lane keeping controller delivers the adequate angles in order to stabilize the vehicle’s trajectory in an optimal way. Two degree of freedom linear bicycle model is adopted as vehicle model, consisting of lateral and yaw motion equations. The proposed control maintains the lateral stability by taking the feedback information from the vehicle transducers. In this way only the lateral vehicle’s dynamics are enough to considerate. Based on the obtained linear mathematical model the quadratic optimal control is designed in order to maintain the lateral stability of the electric vehicle. The numerical simulation results demonstrate the feasibility of the proposed solution.

  12. Optimization of a pressure control valve for high power automatic transmission considering stability

    Science.gov (United States)

    Jian, Hongchao; Wei, Wei; Li, Hongcai; Yan, Qingdong

    2018-02-01

    The pilot-operated electrohydraulic clutch-actuator system is widely utilized by high power automatic transmission because of the demand of large flowrate and the excellent pressure regulating capability. However, a self-excited vibration induced by the inherent non-linear characteristics of valve spool motion coupled with the fluid dynamics can be generated during the working state of hydraulic systems due to inappropriate system parameters, which causes sustaining instability in the system and leads to unexpected performance deterioration and hardware damage. To ensure a stable and fast response performance of the clutch actuator system, an optimal design method for the pressure control valve considering stability is proposed in this paper. A non-linear dynamic model of the clutch actuator system is established based on the motion of the valve spool and coupling fluid dynamics in the system. The stability boundary in the parameter space is obtained by numerical stability analysis. Sensitivity of the stability boundary and output pressure response time corresponding to the valve parameters are identified using design of experiment (DOE) approach. The pressure control valve is optimized using particle swarm optimization (PSO) algorithm with the stability boundary as constraint. The simulation and experimental results reveal that the optimization method proposed in this paper helps in improving the response characteristics while ensuring the stability of the clutch actuator system during the entire gear shift process.

  13. Optimal community structure for social contagions

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    Su, Zhen; Wang, Wei; Li, Lixiang; Stanley, H. Eugene; Braunstein, Lidia A.

    2018-05-01

    Community structure is an important factor in the behavior of real-world networks because it strongly affects the stability and thus the phase transition order of the spreading dynamics. We here propose a reversible social contagion model of community networks that includes the factor of social reinforcement. In our model an individual adopts a social contagion when the number of received units of information exceeds its adoption threshold. We use mean-field approximation to describe our proposed model, and the results agree with numerical simulations. The numerical simulations and theoretical analyses both indicate that there is a first-order phase transition in the spreading dynamics, and that a hysteresis loop emerges in the system when there is a variety of initially adopted seeds. We find an optimal community structure that maximizes spreading dynamics. We also find a rich phase diagram with a triple point that separates the no-diffusion phase from the two diffusion phases.

  14. Dependability of self-optimizing mechatronic systems

    CERN Document Server

    Rammig, Franz; Schäfer, Wilhelm; Sextro, Walter

    2014-01-01

    Intelligent technical systems, which combine mechanical, electrical and software engineering with control engineering and advanced mathematics, go far beyond the state of the art in mechatronics and open up fascinating perspectives. Among these systems are so-called self-optimizing systems, which are able to adapt their behavior autonomously and flexibly to changing operating conditions. Self-optimizing systems create high value for example in terms of energy and resource efficiency as well as reliability. The Collaborative Research Center 614 "Self-optimizing Concepts and Structures in Mechanical Engineering" pursued the long-term aim to open up the active paradigm of self-optimization for mechanical engineering and to enable others to develop self-optimizing systems. This book is directed to researchers and practitioners alike. It provides a design methodology for the development of self-optimizing systems consisting of a reference process, methods, and tools. The reference process is divided into two phase...

  15. Sheltering the self from the storm: self-construal abstractness and the stability of self-esteem.

    Science.gov (United States)

    Updegraff, John A; Emanuel, Amber S; Suh, Eunkook M; Gallagher, Kristel M

    2010-01-01

    Self-construal abstractness (SCA) refers to the degree to which people construe important bases of self-esteem in a broad, flexible, and abstract rather than a concrete and specific manner. This article hypothesized that SCA would be a unique predictor of self-esteem stability, capturing the degree to which people's most important bases of self-worth are resistant to disconfirmation. Two studies using a daily diary methodology examined relationships between SCA, daily self-esteem, and daily emotions and/or events. In Study 1, individual differences in SCA emerged as the most consistent and unique predictor of self-esteem stability. Furthermore, SCA contributed to self-esteem stability by buffering the influence of daily negative emotions on self-esteem. Study 2 manipulated SCA via a daily self-construal task and found an abstract versus concrete self-focus to buffer the influence of daily negative events on self-esteem. Implications of these findings for the study of the self and well-being are discussed.

  16. Byzantine-fault tolerant self-stabilizing protocol for distributed clock synchronization systems

    Science.gov (United States)

    Malekpour, Mahyar R. (Inventor)

    2010-01-01

    A rapid Byzantine self-stabilizing clock synchronization protocol that self-stabilizes from any state, tolerates bursts of transient failures, and deterministically converges within a linear convergence time with respect to the self-stabilization period. Upon self-stabilization, all good clocks proceed synchronously. The Byzantine self-stabilizing clock synchronization protocol does not rely on any assumptions about the initial state of the clocks. Furthermore, there is neither a central clock nor an externally generated pulse system. The protocol converges deterministically, is scalable, and self-stabilizes in a short amount of time. The convergence time is linear with respect to the self-stabilization period.

  17. Measuring self-esteem in context: the importance of stability of self-esteem in psychological functioning.

    Science.gov (United States)

    Kernis, Michael H

    2005-12-01

    In this article, I report on a research program that has focused on the joint roles of stability and level of self-esteem in various aspects of psychological functioning. Stability of self-esteem refers to the magnitude of short-term fluctuations that people experience in their current, contextually based feelings of self-worth. In contrast, level of self-esteem refers to representations of people's general, or typical, feelings of self-worth. A considerable amount of research reveals that self-esteem stability has predictive value beyond the predictive value of self-esteem level. Moreover, considering self-esteem stability provides one way to distinguish fragile from secure forms of high self-esteem. Results from a number of studies are presented and theoretical implications are discussed.

  18. Self-regulating and self-evolving particle swarm optimizer

    Science.gov (United States)

    Wang, Hui-Min; Qiao, Zhao-Wei; Xia, Chang-Liang; Li, Liang-Yu

    2015-01-01

    In this article, a novel self-regulating and self-evolving particle swarm optimizer (SSPSO) is proposed. Learning from the idea of direction reversal, self-regulating behaviour is a modified position update rule for particles, according to which the algorithm improves the best position to accelerate convergence in situations where the traditional update rule does not work. Borrowing the idea of mutation from evolutionary computation, self-evolving behaviour acts on the current best particle in the swarm to prevent the algorithm from prematurely converging. The performance of SSPSO and four other improved particle swarm optimizers is numerically evaluated by unimodal, multimodal and rotated multimodal benchmark functions. The effectiveness of SSPSO in solving real-world problems is shown by the magnetic optimization of a Halbach-based permanent magnet machine. The results show that SSPSO has good convergence performance and high reliability, and is well matched to actual problems.

  19. Self-esteem stability in relation to narcissism and psychological well-being

    Directory of Open Access Journals (Sweden)

    Saša Zorjan

    2013-06-01

    Full Text Available The concept of self-esteem stability has an important role in the understanding of interpersonal and psychological functioning of individuals. The purpose of this study was to examine the relationship between self-esteem stability, narcissism and psychological well-being. A total of 178 participants (77% female participated in this study. The average age of the participants was 20, with the ages ranging from 18 to 26 years. The participants completed the following scales and questionnaires: Narcissistic Personality Inventory (NPI, Psychological Well-being Scales (PWBS, Instability of Selfesteem scale (ISES and Rosenberg Self-esteem scale (RSES. The Rosenberg Self-esteem scale was used to measure both self-esteem level and self-esteem stability, which was defined as dispersion of self-esteem level in time. For the purpose of obtaining data on self-esteem stability, the participants were required complete the Rosenberg self-esteem scale for a sequence of 14 days, other measures were completed during the first day of participation in the study. The main effects for self-esteem level emerged for narcissism and psychological well-being, in both cases higher levels of self-esteem was associated to higher levels of narcissism and psychological well-being. Self-esteem stability additionally explained a significant proportion of variability in narcissism and psychological well-being. Self-esteem stability was negatively associated with higher levels of narcissism and positively associated with higher levels of psychological well-being, above and beyond the effect of self-esteem level. When comparing two different measures of self-esteem stability, the results revealed that people with higher level of narcissism tend to overestimate their self-esteem stability. The results were consistent with our hypotheses. The importance of considering both level and stability of self-esteem, limitations of the present study and possibilities for further research are

  20. Self-Configuration and Self-Optimization Process in Heterogeneous Wireless Networks

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    Eduardo Camponogara

    2010-12-01

    Full Text Available Self-organization in Wireless Mesh Networks (WMN is an emergent research area, which is becoming important due to the increasing number of nodes in a network. Consequently, the manual configuration of nodes is either impossible or highly costly. So it is desirable for the nodes to be able to configure themselves. In this paper, we propose an alternative architecture for self-organization of WMN based on Optimized Link State Routing Protocol (OLSR and the ad hoc on demand distance vector (AODV routing protocols as well as using the technology of software agents. We argue that the proposed self-optimization and self-configuration modules increase the throughput of network, reduces delay transmission and network load, decreases the traffic of HELLO messages according to network’s scalability. By simulation analysis, we conclude that the self-optimization and self-configuration mechanisms can significantly improve the performance of OLSR and AODV protocols in comparison to the baseline protocols analyzed.

  1. Self-Configuration and Self-Optimization Process in Heterogeneous Wireless Networks

    Science.gov (United States)

    Guardalben, Lucas; Villalba, Luis Javier García; Buiati, Fábio; Sobral, João Bosco Mangueira; Camponogara, Eduardo

    2011-01-01

    Self-organization in Wireless Mesh Networks (WMN) is an emergent research area, which is becoming important due to the increasing number of nodes in a network. Consequently, the manual configuration of nodes is either impossible or highly costly. So it is desirable for the nodes to be able to configure themselves. In this paper, we propose an alternative architecture for self-organization of WMN based on Optimized Link State Routing Protocol (OLSR) and the ad hoc on demand distance vector (AODV) routing protocols as well as using the technology of software agents. We argue that the proposed self-optimization and self-configuration modules increase the throughput of network, reduces delay transmission and network load, decreases the traffic of HELLO messages according to network’s scalability. By simulation analysis, we conclude that the self-optimization and self-configuration mechanisms can significantly improve the performance of OLSR and AODV protocols in comparison to the baseline protocols analyzed. PMID:22346584

  2. Michelson mode selector for spectral range stabilization in a self-sweeping fiber laser.

    Science.gov (United States)

    Tkachenko, A Yu; Vladimirskaya, A D; Lobach, I A; Kablukov, S I

    2018-04-01

    We report on spectral range stabilization in a self-sweeping laser by adding a narrowband fiber Bragg grating (FBG) to the output mirror in the Michelson configuration. The effects of FBG reflectivity and optical path difference in the Michelson interferometer on the laser spectral dynamics are investigated. Optimization of the interferometer allows us to demonstrate broadband (over 16 nm) self-sweeping operation and reduction of the start and stop wavelength fluctuations by two orders and one order of magnitude (∼100 and 15 times) for start and stop bounds, respectively (down to several picometers). The proposed approaches significantly improve quality of the spectral dynamics and facilitate application of the self-sweeping lasers.

  3. Optimal control theory applied to fusion plasma thermal stabilization

    International Nuclear Information System (INIS)

    Sager, G.; Miley, G.; Maya, I.

    1985-01-01

    Many authors have investigated stability characteristics and performance of various burn control schemes. The work presented here represents the first application of optimal control theory to the problem of fusion plasma thermal stabilization. The objectives of this initial investigation were to develop analysis methods, demonstrate tractability, and present some preliminary results of optimal control theory in burn control research

  4. Strong stabilization servo controller with optimization of performance criteria.

    Science.gov (United States)

    Sarjaš, Andrej; Svečko, Rajko; Chowdhury, Amor

    2011-07-01

    Synthesis of a simple robust controller with a pole placement technique and a H(∞) metrics is the method used for control of a servo mechanism with BLDC and BDC electric motors. The method includes solving a polynomial equation on the basis of the chosen characteristic polynomial using the Manabe standard polynomial form and parametric solutions. Parametric solutions are introduced directly into the structure of the servo controller. On the basis of the chosen parametric solutions the robustness of a closed-loop system is assessed through uncertainty models and assessment of the norm ‖•‖(∞). The design procedure and the optimization are performed with a genetic algorithm differential evolution - DE. The DE optimization method determines a suboptimal solution throughout the optimization on the basis of a spectrally square polynomial and Šiljak's absolute stability test. The stability of the designed controller during the optimization is being checked with Lipatov's stability condition. Both utilized approaches: Šiljak's test and Lipatov's condition, check the robustness and stability characteristics on the basis of the polynomial's coefficients, and are very convenient for automated design of closed-loop control and for application in optimization algorithms such as DE. Copyright © 2011 ISA. Published by Elsevier Ltd. All rights reserved.

  5. PSYCHOLOGICAL APPROACHES TO STUDY OF OPTIMAL MANAGEMENT ACTIVITIES IN LEADERS OF ETHNIC COMMUNITY ORGANIZATIONS

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    N T Kolesnik

    2015-12-01

    Full Text Available The article describes the main psychological approaches, and in particular, the system-synergetic approach to the study of the management activities of the leaders of ethnic community organizations. It also discusses the concept and essence of social self-organization of the ethnic group. It presents the methodological framework of the synergetic approach to the consideration of the study of complex self-organizing systems. The analysis of conditions of effectiveness of the process of self-organization of ethnic public associations is given. The basic principles of modern psychology of labor, which form the basis for the research of the optimal management activity of the leaders of ethnic community organizations, are highlighted. The presented theoretical analysis led to the conclusion that the integral research of the management activities of the heads of ethnic community organizations may be based on the psychological system-synergetic approach, from the point of which the management activities could be presented as a psychologically complex and open system.

  6. Self-esteem and optimism in rural youth: gender differences.

    Science.gov (United States)

    Puskar, Kathryn R; Bernardo, Lisa Marie; Ren, Dianxu; Haley, Tammy M; Tark, Kirsti Hetager; Switala, Joann; Siemon, Linda

    2010-01-01

    To identify and describe gender-related differences in the self-esteem and optimism levels of rural adolescents. Self-esteem and optimism have been broadly examined and are associated with health-practices, social interaction, attachment, resiliency, and personal identity. Information describing the relationship of self-esteem and optimism as it relates to gender is limited. Using a cross-sectional survey design, students (N = 193) from three high-schools in rural Pennsylvania, USA completed the Rosenberg Self-Esteem Scale and the Optimism Scale-Life Orientation Test-Revised as part of a National Institute of Health, National Institute of Nursing Research funded study. Both instruments' mean scores were in the range of average for this population, with females scoring lower than males in both self-esteem (p self-esteem and optimism. Attention to self-esteem and optimism in female youth is recommended.

  7. Generating functions and stability study of multivariate self-excited epidemic processes

    Science.gov (United States)

    Saichev, A. I.; Sornette, D.

    2011-09-01

    We present a stability study of the class of multivariate self-excited Hawkes point processes, that can model natural and social systems, including earthquakes, epileptic seizures and the dynamics of neuron assemblies, bursts of exchanges in social communities, interactions between Internet bloggers, bank network fragility and cascading of failures, national sovereign default contagion, and so on. We present the general theory of multivariate generating functions to derive the number of events over all generations of various types that are triggered by a mother event of a given type. We obtain the stability domains of various systems, as a function of the topological structure of the mutual excitations across different event types. We find that mutual triggering tends to provide a significant extension of the stability (or subcritical) domain compared with the case where event types are decoupled, that is, when an event of a given type can only trigger events of the same type.

  8. A self-adaptive thermal switch array for rapid temperature stabilization under various thermal power inputs

    International Nuclear Information System (INIS)

    Geng, Xiaobao; Patel, Pragnesh; Narain, Amitabh; Meng, Dennis Desheng

    2011-01-01

    A self-adaptive thermal switch array (TSA) based on actuation by low-melting-point alloy droplets is reported to stabilize the temperature of a heat-generating microelectromechanical system (MEMS) device at a predetermined range (i.e. the optimal working temperature of the device) with neither a control circuit nor electrical power consumption. When the temperature is below this range, the TSA stays off and works as a thermal insulator. Therefore, the MEMS device can quickly heat itself up to its optimal working temperature during startup. Once this temperature is reached, TSA is automatically turned on to increase the thermal conductance, working as an effective thermal spreader. As a result, the MEMS device tends to stay at its optimal working temperature without complex thermal management components and the associated parasitic power loss. A prototype TSA was fabricated and characterized to prove the concept. The stabilization temperatures under various power inputs have been studied both experimentally and theoretically. Under the increment of power input from 3.8 to 5.8 W, the temperature of the device increased only by 2.5 °C due to the stabilization effect of TSA

  9. Assessing control of postural stability in community-living older adults using performance-based limits of stability

    Directory of Open Access Journals (Sweden)

    Boissy Patrick

    2008-03-01

    Full Text Available Abstract Background Balance disability measurements routinely used to identify fall risks in frail populations have limited value in the early detection of postural stability deficits in community-living older adults. The objectives of the study were to 1 measure performance-based limits of stability (LOS in community-living older adults and compare them to theoretical LOS computed from data proposed by the Balance Master® system, 2 explore the feasibility of a new measurement approach based on the assessment of postural stability during weight-shifting tasks at performance-based LOS, 3 quantify intra-session performance variability during multiple trials using the performance-based LOS paradigm. Methods Twenty-four healthy community-living older adults (10 men, 14 women aged between 62 to 85 (mean age ± sd, 71.5 ± 6 yrs participated in the study. Subjects' performance-based LOS were established by asking them to transfer their body weight as far as possible in three directions (forward, right and left without changing their base of support. LOS were computed as the maximal excursion of the COP in each direction among three trials. Participants then performed two experimental tasks that consisted in controlling, with the assistance of visual feedback, their centre of pressure (COP within two predefined targets set at 100% of their performance-based LOS. For each tasks 8 trials were performed. Ground reaction forces and torques during performance-based LOS evaluation and experimental tasks were recorded with a force plate. Sway area and medio-lateral mean COP displacement speed variables were extracted from force plate recordings. Results Significant differences between theoretical LOS computed from maximum leaning angles derived from anthropometric characteristics and performance-based LOS were observed. Results showed that a motor learning effect was present as the participants optimized their weight-shifting strategy through the first three

  10. Confinement of a self-stabilized tokamak under average magnetic well conditions

    International Nuclear Information System (INIS)

    Demchenko, V.V.; Fu, G.Y.; Van Dam, J.W.

    1987-05-01

    It is well known that the average favorable magnetic curvature of a tokamak is stabilizing with respect to pressure-driven magnetohydrodynamic instabilities at low beta and that self-stabilization occurs at finite beta in the so-called second stability regime. Here we self-consistently investigate how these two effects, viz., the mean magnetic well and the self-stabilization, influence the energy confinement time in a tokamak, using the ballooning mode transport model

  11. Optimized formulation of solid self-microemulsifying sirolimus delivery systems

    Directory of Open Access Journals (Sweden)

    Cho W

    2013-04-01

    Full Text Available Wonkyung Cho,1,2 Min-Soo Kim,3 Jeong-Soo Kim,2 Junsung Park,1,2 Hee Jun Park,1,2 Kwang-Ho Cha,1,2 Jeong-Sook Park,2 Sung-Joo Hwang1,4 1Yonsei Institute of Pharmaceutical Sciences, Yonsei University, Incheon, Republic of Korea; 2College of Pharmacy, Chungnam National University, Daejeon, Republic of Korea; 3Department of Pharmaceutical Engineering, Inje University, Gimhae, Republic of Korea; 4College of Pharmacy, Yonsei University, Incheon, Republic of Korea Background: The aim of this study was to develop an optimized solid self-microemulsifying drug delivery system (SMEDDS formulation for sirolimus to enhance its solubility, stability, and bioavailability. Methods: Excipients used for enhancing the solubility and stability of sirolimus were screened. A phase-separation test, visual observation for emulsifying efficiency, and droplet size analysis were performed. Ternary phase diagrams were constructed to optimize the liquid SMEDDS formulation. The selected liquid SMEDDS formulations were prepared into solid form. The dissolution profiles and pharmacokinetic profiles in rats were analyzed. Results: In the results of the oil and cosolvent screening studies, Capryol™ Propylene glycol monocaprylate (PGMC and glycofurol exhibited the highest solubility of all oils and cosolvents, respectively. In the surfactant screening test, D-α-tocopheryl polyethylene glycol 1000 succinate (vitamin E TPGS was determined to be the most effective stabilizer of sirolimus in pH 1.2 simulated gastric fluids. The optimal formulation determined by the construction of ternary phase diagrams was the T32 (Capryol™ PGMC:glycofurol:vitamin E TPGS = 30:30:40 weight ratio formulation with a mean droplet size of 108.2 ± 11.4 nm. The solid SMEDDS formulations were prepared with Sucroester 15 and mannitol. The droplet size of the reconstituted solid SMEDDS showed no significant difference compared with the liquid SMEDDS. In the dissolution study, the release amounts of

  12. Genetic influences on level and stability of self-esteem

    OpenAIRE

    Neiss, Michelle; Sedikides, Constantine; Stevenson, Jim

    2006-01-01

    We attempted to clarify the relation between self-esteem level (high vs. low) and perceived self-esteem stability (within-person variability) by using a behavioral genetics approach. We tested whether the same or independent genetic and environmental influences impact on level and stability. Adolescent twin siblings (n = 183 pairs) completed level and stability scales at two time points. Heritability for both was substantial. The remaining variance in each was attributable to non-shared envir...

  13. Self-Optimization of LTE Networks Utilizing Celnet Xplorer

    CERN Document Server

    Buvaneswari, A; Polakos, Paul; Buvaneswari, Arumugam

    2010-01-01

    In order to meet demanding performance objectives in Long Term Evolution (LTE) networks, it is mandatory to implement highly efficient, autonomic self-optimization and configuration processes. Self-optimization processes have already been studied in second generation (2G) and third generation (3G) networks, typically with the objective of improving radio coverage and channel capacity. The 3rd Generation Partnership Project (3GPP) standard for LTE self-organization of networks (SON) provides guidelines on self-configuration of physical cell ID and neighbor relation function and self-optimization for mobility robustness, load balancing, and inter-cell interference reduction. While these are very important from an optimization perspective of local phenomenon (i.e., the eNodeB's interaction with its neighbors), it is also essential to architect control algorithms to optimize the network as a whole. In this paper, we propose a Celnet Xplorer-based SON architecture that allows detailed analysis of network performan...

  14. Soil communities promote temporal stability and species asynchrony in experimental grassland communities

    NARCIS (Netherlands)

    Pellkofer, Sarah; Van Der Heijden, Marcel G A; Schmid, Bernhard; Wagg, Cameron

    2016-01-01

    Background Over the past two decades many studies have demonstrated that plant species diversity promotes primary productivity and stability in grassland ecosystems. Additionally, soil community characteristics have also been shown to influence the productivity and composition of plant communities,

  15. A no-go theorem for a two-dimensional self-correcting quantum memory based on stabilizer codes

    International Nuclear Information System (INIS)

    Bravyi, Sergey; Terhal, Barbara

    2009-01-01

    We study properties of stabilizer codes that permit a local description on a regular D-dimensional lattice. Specifically, we assume that the stabilizer group of a code (the gauge group for subsystem codes) can be generated by local Pauli operators such that the support of any generator is bounded by a hypercube of size O(1). Our first result concerns the optimal scaling of the distance d with the linear size of the lattice L. We prove an upper bound d=O(L D-1 ) which is tight for D=1, 2. This bound applies to both subspace and subsystem stabilizer codes. Secondly, we analyze the suitability of stabilizer codes for building a self-correcting quantum memory. Any stabilizer code with geometrically local generators can be naturally transformed to a local Hamiltonian penalizing states that violate the stabilizer condition. A degenerate ground state of this Hamiltonian corresponds to the logical subspace of the code. We prove that for D=1, 2, different logical states can be mapped into each other by a sequence of single-qubit Pauli errors such that the energy of all intermediate states is upper bounded by a constant independent of the lattice size L. The same result holds if there are unused logical qubits that are treated as 'gauge qubits'. It demonstrates that a self-correcting quantum memory cannot be built using stabilizer codes in dimensions D=1, 2. This result is in sharp contrast with the existence of a classical self-correcting memory in the form of a two-dimensional (2D) ferromagnet. Our results leave open the possibility for a self-correcting quantum memory based on 2D subsystem codes or on 3D subspace or subsystem codes.

  16. Fluctuating interaction network and time-varying stability of a natural fish community

    Science.gov (United States)

    Ushio, Masayuki; Hsieh, Chih-Hao; Masuda, Reiji; Deyle, Ethan R.; Ye, Hao; Chang, Chun-Wei; Sugihara, George; Kondoh, Michio

    2018-02-01

    Ecological theory suggests that large-scale patterns such as community stability can be influenced by changes in interspecific interactions that arise from the behavioural and/or physiological responses of individual species varying over time. Although this theory has experimental support, evidence from natural ecosystems is lacking owing to the challenges of tracking rapid changes in interspecific interactions (known to occur on timescales much shorter than a generation time) and then identifying the effect of such changes on large-scale community dynamics. Here, using tools for analysing nonlinear time series and a 12-year-long dataset of fortnightly collected observations on a natural marine fish community in Maizuru Bay, Japan, we show that short-term changes in interaction networks influence overall community dynamics. Among the 15 dominant species, we identify 14 interspecific interactions to construct a dynamic interaction network. We show that the strengths, and even types, of interactions change with time; we also develop a time-varying stability measure based on local Lyapunov stability for attractor dynamics in non-equilibrium nonlinear systems. We use this dynamic stability measure to examine the link between the time-varying interaction network and community stability. We find seasonal patterns in dynamic stability for this fish community that broadly support expectations of current ecological theory. Specifically, the dominance of weak interactions and higher species diversity during summer months are associated with higher dynamic stability and smaller population fluctuations. We suggest that interspecific interactions, community network structure and community stability are dynamic properties, and that linking fluctuating interaction networks to community-level dynamic properties is key to understanding the maintenance of ecological communities in nature.

  17. Self-stability analysis of MHTGRs: A shifted-ectropy based approach

    International Nuclear Information System (INIS)

    Dong Zhe

    2012-01-01

    Highlights: ► In this paper, self-stability of the MHTGR is analyzed from a physical viewpoint. ► A shifted-ectropy method for self-stability analysis of general thermodynamic systems is established. ► Then it is proved theoretically that the equilibriums of the MHTGR are globally asymptotically stable. ► Numerical verification results are consistent with the theoretical result. - Abstract: Because of the strong inherent safety, the modular high temperature gas-cooled nuclear reactor (MHTGR) has been seen as the chosen technology for the next generation of nuclear power plants (NPPs). Self-stability of a nuclear reactor, which is the ability that the reactor state can converge to an equilibrium point without control input, has great meaning in designing control and operation strategies for the NPPs based on MHTGR technology. In this paper, self-stability of the MHTGR is analyzed from a physical viewpoint. A shifted-ectropy method for analyzing the stability of the equilibriums of general thermodynamic systems is firstly established. Based upon this approach, it is proved theoretically that the equilibriums of the MHTGR dynamics are globally asymptotically stable. Numerical simulation results, which illustrate the MHTGR self-stability feature directly, are consistent with the theoretical result.

  18. Self-stabilized pinch (SSP) concept

    International Nuclear Information System (INIS)

    Sugisaki, Kiwamu; Hirano, Keiichi.

    1985-01-01

    Self-Stabilized pinch (SSP) consept is revealed. SSP providcs many attractive features for application to a fusion reactor. Design studies for high temperature plasma production are carried out. Use of adiabatic compression leads to a remarkable reduction of required power source. (author)

  19. Stabilized quasi-Newton optimization of noisy potential energy surfaces

    Energy Technology Data Exchange (ETDEWEB)

    Schaefer, Bastian; Goedecker, Stefan, E-mail: stefan.goedecker@unibas.ch [Department of Physics, University of Basel, Klingelbergstrasse 82, CH-4056 Basel (Switzerland); Alireza Ghasemi, S. [Institute for Advanced Studies in Basic Sciences, P.O. Box 45195-1159, IR-Zanjan (Iran, Islamic Republic of); Roy, Shantanu [Computational and Systems Biology, Biozentrum, University of Basel, CH-4056 Basel (Switzerland)

    2015-01-21

    Optimizations of atomic positions belong to the most commonly performed tasks in electronic structure calculations. Many simulations like global minimum searches or characterizations of chemical reactions require performing hundreds or thousands of minimizations or saddle computations. To automatize these tasks, optimization algorithms must not only be efficient but also very reliable. Unfortunately, computational noise in forces and energies is inherent to electronic structure codes. This computational noise poses a severe problem to the stability of efficient optimization methods like the limited-memory Broyden–Fletcher–Goldfarb–Shanno algorithm. We here present a technique that allows obtaining significant curvature information of noisy potential energy surfaces. We use this technique to construct both, a stabilized quasi-Newton minimization method and a stabilized quasi-Newton saddle finding approach. We demonstrate with the help of benchmarks that both the minimizer and the saddle finding approach are superior to comparable existing methods.

  20. Stabilized quasi-Newton optimization of noisy potential energy surfaces

    International Nuclear Information System (INIS)

    Schaefer, Bastian; Goedecker, Stefan; Alireza Ghasemi, S.; Roy, Shantanu

    2015-01-01

    Optimizations of atomic positions belong to the most commonly performed tasks in electronic structure calculations. Many simulations like global minimum searches or characterizations of chemical reactions require performing hundreds or thousands of minimizations or saddle computations. To automatize these tasks, optimization algorithms must not only be efficient but also very reliable. Unfortunately, computational noise in forces and energies is inherent to electronic structure codes. This computational noise poses a severe problem to the stability of efficient optimization methods like the limited-memory Broyden–Fletcher–Goldfarb–Shanno algorithm. We here present a technique that allows obtaining significant curvature information of noisy potential energy surfaces. We use this technique to construct both, a stabilized quasi-Newton minimization method and a stabilized quasi-Newton saddle finding approach. We demonstrate with the help of benchmarks that both the minimizer and the saddle finding approach are superior to comparable existing methods

  1. Optimal boundary control and boundary stabilization of hyperbolic systems

    CERN Document Server

    Gugat, Martin

    2015-01-01

    This brief considers recent results on optimal control and stabilization of systems governed by hyperbolic partial differential equations, specifically those in which the control action takes place at the boundary.  The wave equation is used as a typical example of a linear system, through which the author explores initial boundary value problems, concepts of exact controllability, optimal exact control, and boundary stabilization.  Nonlinear systems are also covered, with the Korteweg-de Vries and Burgers Equations serving as standard examples.  To keep the presentation as accessible as possible, the author uses the case of a system with a state that is defined on a finite space interval, so that there are only two boundary points where the system can be controlled.  Graduate and post-graduate students as well as researchers in the field will find this to be an accessible introduction to problems of optimal control and stabilization.

  2. classical optimization of bagasse ash content in cement-stabilized

    African Journals Online (AJOL)

    Optimization of construction materials with laboratory data is a very possible way of minimizing waste of resources (materials and cost). There had been several successful attempts of optimization of construction materials. However, optimization in soil stabilization for road-work has been very rare because of its complexities ...

  3. Production of Low Cost Carbon-Fiber through Energy Optimization of Stabilization Process

    Directory of Open Access Journals (Sweden)

    Gelayol Golkarnarenji

    2018-03-01

    Full Text Available To produce high quality and low cost carbon fiber-based composites, the optimization of the production process of carbon fiber and its properties is one of the main keys. The stabilization process is the most important step in carbon fiber production that consumes a large amount of energy and its optimization can reduce the cost to a large extent. In this study, two intelligent optimization techniques, namely Support Vector Regression (SVR and Artificial Neural Network (ANN, were studied and compared, with a limited dataset obtained to predict physical property (density of oxidative stabilized PAN fiber (OPF in the second zone of a stabilization oven within a carbon fiber production line. The results were then used to optimize the energy consumption in the process. The case study can be beneficial to chemical industries involving carbon fiber manufacturing, for assessing and optimizing different stabilization process conditions at large.

  4. Optimizing social participation in community-dwelling older adults through the use of behavioral coping strategies.

    Science.gov (United States)

    Provencher, Véronique; Desrosiers, Johanne; Demers, Louise; Carmichael, Pierre-Hugues

    2016-01-01

    This study aimed to (1) determine the categories of behavioral coping strategies most strongly correlated with optimal seniors' social participation in different activity and role domains and (2) identify the demographic, health and environmental factors associated with the use of these coping strategies optimizing social participation. The sample consisted of 350 randomly recruited community-dwelling older adults (≥65 years). Coping strategies and social participation were measured, respectively, using the Inventory of Coping Strategies Used by the Elderly and Assessment of Life Habits questionnaires. Information about demographic, health and environmental factors was also collected during the interview. Regression analyses showed a strong relationship between the use of cooking- and transportation-related coping strategies and optimal participation in the domains of nutrition and community life, respectively. Older age and living alone were associated with increased use of cooking-related strategies, while good self-rated health and not living in a seniors' residence were correlated with greater use of transportation-related strategies. Our study helped to identify useful behavioral coping strategies that should be incorporated in disability prevention programs designed to promote community-dwelling seniors' social participation. However, the appropriateness of these strategies depends on whether they are used in relevant contexts and tailored to specific needs. Our results support the relevance of including behavioral coping strategies related to cooking and transportation in disability prevention programs designed to promote community-dwelling seniors' social participation in the domains of nutrition and community life, respectively. Older age and living alone were associated with increased use of cooking-related strategies, while good self-rated health and not living in a seniors' residence were correlated with greater use of transportation

  5. An Optimal Power Flow (OPF) Method with Improved Power System Stability

    DEFF Research Database (Denmark)

    Su, Chi; Chen, Zhe

    2010-01-01

    This paper proposes an optimal power flow (OPF) method taking into account small signal stability as additional constraints. Particle swarm optimization (PSO) algorithm is adopted to realize the OPF process. The method is programmed in MATLAB and implemented to a nine-bus test power system which...... has large-scale wind power integration. The results show the ability of the proposed method to find optimal (or near-optimal) operating points in different cases. Based on these results, the analysis of the impacts of wind power integration on the system small signal stability has been conducted....

  6. Building Action for Stability in Communities (BASIC) : Training for ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    The BASIC approach combines demographic, health and environmental management tools to increase community stability and wellbeing. Following the training, the participants will undertake community population appraisals, environmental planning and health service delivery planning in their own communities. Two pilot ...

  7. Game Theoretical Analysis on Cooperation Stability and Incentive Effectiveness in Community Networks.

    Science.gov (United States)

    Song, Kaida; Wang, Rui; Liu, Yi; Qian, Depei; Zhang, Han; Cai, Jihong

    2015-01-01

    Community networks, the distinguishing feature of which is membership admittance, appear on P2P networks, social networks, and conventional Web networks. Joining the network costs money, time or network bandwidth, but the individuals get access to special resources owned by the community in return. The prosperity and stability of the community are determined by both the policy of admittance and the attraction of the privileges gained by joining. However, some misbehaving users can get the dedicated resources with some illicit and low-cost approaches, which introduce instability into the community, a phenomenon that will destroy the membership policy. In this paper, we analyze on the stability using game theory on such a phenomenon. We propose a game-theoretical model of stability analysis in community networks and provide conditions for a stable community. We then extend the model to analyze the effectiveness of different incentive policies, which could be used when the community cannot maintain its members in certain situations. Then we verify those models through a simulation. Finally, we discuss several ways to promote community network's stability by adjusting the network's properties and give some proposal on the designs of these types of networks from the points of game theory and stability.

  8. Game Theoretical Analysis on Cooperation Stability and Incentive Effectiveness in Community Networks.

    Directory of Open Access Journals (Sweden)

    Kaida Song

    Full Text Available Community networks, the distinguishing feature of which is membership admittance, appear on P2P networks, social networks, and conventional Web networks. Joining the network costs money, time or network bandwidth, but the individuals get access to special resources owned by the community in return. The prosperity and stability of the community are determined by both the policy of admittance and the attraction of the privileges gained by joining. However, some misbehaving users can get the dedicated resources with some illicit and low-cost approaches, which introduce instability into the community, a phenomenon that will destroy the membership policy. In this paper, we analyze on the stability using game theory on such a phenomenon. We propose a game-theoretical model of stability analysis in community networks and provide conditions for a stable community. We then extend the model to analyze the effectiveness of different incentive policies, which could be used when the community cannot maintain its members in certain situations. Then we verify those models through a simulation. Finally, we discuss several ways to promote community network's stability by adjusting the network's properties and give some proposal on the designs of these types of networks from the points of game theory and stability.

  9. Optimizing delivery of recovery-oriented online self-management strategies for bipolar disorder: a review.

    Science.gov (United States)

    Leitan, Nuwan D; Michalak, Erin E; Berk, Lesley; Berk, Michael; Murray, Greg

    2015-03-01

    Self-management is emerging as a viable alternative to difficult-to-access psychosocial treatments for bipolar disorder (BD), and has particular relevance to recovery-related goals around empowerment and personal meaning. This review examines data and theory on BD self-management from a recovery-oriented perspective, with a particular focus on optimizing low-intensity delivery of self-management tools via the web. A critical evaluation of various literatures was undertaken. Literatures on recovery, online platforms, and self-management in mental health and BD are reviewed. The literature suggests that the self-management approach aligns with the recovery framework. However, studies have identified a number of potential barriers to the utilization of self-management programs for BD and it has been suggested that utilizing an online environment may be an effective way to surmount many of these barriers. Online self-management programs for BD are rapidly developing, and in parallel the recovery perspective is becoming the dominant paradigm for mental health services worldwide, so research is urgently required to assess the efficacy and safety of optimization methods such as professional and/or peer support, tailoring and the development of 'online communities'. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  10. Optimization of planar self-collimating photonic crystals.

    Science.gov (United States)

    Rumpf, Raymond C; Pazos, Javier J

    2013-07-01

    Self-collimation in photonic crystals has received a lot of attention in the literature, partly due to recent interest in silicon photonics, yet no performance metrics have been proposed. This paper proposes a figure of merit (FOM) for self-collimation and outlines a methodical approach for calculating it. Performance metrics include bandwidth, angular acceptance, strength, and an overall FOM. Two key contributions of this work include the performance metrics and identifying that the optimum frequency for self-collimation is not at the inflection point. The FOM is used to optimize a planar photonic crystal composed of a square array of cylinders. Conclusions are drawn about how the refractive indices and fill fraction of the lattice impact each of the performance metrics. The optimization is demonstrated by simulating two spatially variant self-collimating photonic crystals, where one has a high FOM and the other has a low FOM. This work gives optical designers tremendous insight into how to design and optimize robust self-collimating photonic crystals, which promises many applications in silicon photonics and integrated optics.

  11. Propositional Optimal Trajectory Programming for Improving Stability ...

    African Journals Online (AJOL)

    Propositional Optimal Trajectory Programming for Improving Stability of Hermite Definite Control System. ... PROMOTING ACCESS TO AFRICAN RESEARCH. AFRICAN JOURNALS ONLINE (AJOL) ... Knowledge of systems operation subjected to heat diffusion constraints is required of systems analysts. In an instance that ...

  12. Dispositional optimism, self-framing and medical decision-making.

    Science.gov (United States)

    Zhao, Xu; Huang, Chunlei; Li, Xuesong; Zhao, Xin; Peng, Jiaxi

    2015-03-01

    Self-framing is an important but underinvestigated area in risk communication and behavioural decision-making, especially in medical settings. The present study aimed to investigate the relationship among dispositional optimism, self-frame and decision-making. Participants (N = 500) responded to the Life Orientation Test-Revised and self-framing test of medical decision-making problem. The participants whose scores were higher than the middle value were regarded as highly optimistic individuals. The rest were regarded as low optimistic individuals. The results showed that compared to the high dispositional optimism group, participants from the low dispositional optimism group showed a greater tendency to use negative vocabulary to construct their self-frame, and tended to choose the radiation therapy with high treatment survival rate, but low 5-year survival rate. Based on the current findings, it can be concluded that self-framing effect still exists in medical situation and individual differences in dispositional optimism can influence the processing of information in a framed decision task, as well as risky decision-making. © 2014 International Union of Psychological Science.

  13. Interdependent Self-Construal, Self-Efficacy, and Community Involvement as Predictors of Perceived Knowledge Gain Among MMORPG Players.

    Science.gov (United States)

    Hopp, Toby; Barker, Valerie; Schmitz Weiss, Amy

    2015-08-01

    This study explored the relationship between interdependent self-construal, video game self-efficacy, massively multiplayer online role-playing game (MMORPG) community involvement, and self-reported learning outcomes. The results suggested that self-efficacy and interdependent self-construal were positive and significant predictors of MMORPG community involvement. For its part, MMORPG community involvement was a positive predictor of self-reported learning in both focused and incidental forms. Supplementary analyses suggested that self-efficacy was a comparatively more robust predictor of MMORPG community involvement when compared to self-construal. Moreover, the present data suggest that community involvement significantly facilitated indirect relationships between self-construal, game-relevant self-efficacy, and both focused and incidental learning.

  14. Pyrosequencing Based Microbial Community Analysis of Stabilized Mine Soils

    Science.gov (United States)

    Park, J. E.; Lee, B. T.; Son, A.

    2015-12-01

    Heavy metals leached from exhausted mines have been causing severe environmental problems in nearby soils and groundwater. Environmental mitigation was performed based on the heavy metal stabilization using Calcite and steel slag in Korea. Since the soil stabilization only temporarily immobilizes the contaminants to soil matrix, the potential risk of re-leaching heavy metal still exists. Therefore the follow-up management of stabilized soils and the corresponding evaluation methods are required to avoid the consequent contamination from the stabilized soils. In this study, microbial community analysis using pyrosequencing was performed for assessing the potential leaching of the stabilized soils. As a result of rarefaction curve and Chao1 and Shannon indices, the stabilized soil has shown lower richness and diversity as compared to non-contaminated negative control. At the phyla level, as the degree of contamination increases, most of phyla decreased with only exception of increased proteobacteria. Among proteobacteria, gamma-proteobacteria increased against the heavy metal contamination. At the species level, Methylobacter tundripaludum of gamma-proteobacteria showed the highest relative portion of microbial community, indicating that methanotrophs may play an important role in either solubilization or immobilization of heavy metals in stabilized soils.

  15. Optimal energy management strategy for self-reconfigurable batteries

    International Nuclear Information System (INIS)

    Bouchhima, Nejmeddine; Schnierle, Marc; Schulte, Sascha; Birke, Kai Peter

    2017-01-01

    This paper proposes a novel energy management strategy for multi-cell high voltage batteries where the current through each cell can be controlled, called self-reconfigurable batteries. An optimized control strategy further enhances the energy efficiency gained by the hardware architecture of those batteries. Currently, achieving cell equalization by using the active balancing circuits is considered as the best way to optimize the energy efficiency of the battery pack. This study demonstrates that optimizing the energy efficiency of self-reconfigurable batteries is no more strongly correlated to the cell balancing. According to the features of this novel battery architecture, the energy management strategy is formulated as nonlinear dynamic optimization problem. To solve this optimal control, an optimization algorithm that generates the optimal discharge policy for a given driving cycle is developed based on dynamic programming and code vectorization. The simulation results show that the designed energy management strategy maximizes the system efficiency across the battery lifetime over conventional approaches. Furthermore, the present energy management strategy can be implemented online due to the reduced complexity of the optimization algorithm. - Highlights: • The energy efficiency of self-reconfigurable batteries is maximized. • The energy management strategy for the battery is formulated as optimal control problem. • Developing an optimization algorithm using dynamic programming techniques and code vectorization. • Simulation studies are conducted to validate the proposed optimal strategy.

  16. Order-2 Stability Analysis of Particle Swarm Optimization.

    Science.gov (United States)

    Liu, Qunfeng

    2015-01-01

    Several stability analyses and stable regions of particle swarm optimization (PSO) have been proposed before. The assumption of stagnation and different definitions of stability are adopted in these analyses. In this paper, the order-2 stability of PSO is analyzed based on a weak stagnation assumption. A new definition of stability is proposed and an order-2 stable region is obtained. Several existing stable analyses for canonical PSO are compared, especially their definitions of stability and the corresponding stable regions. It is shown that the classical stagnation assumption is too strict and not necessary. Moreover, among all these definitions of stability, it is shown that our definition requires the weakest conditions, and additional conditions bring no benefit. Finally, numerical experiments are reported to show that the obtained stable region is meaningful. A new parameter combination of PSO is also shown to be good, even better than some known best parameter combinations.

  17. Individual differences and self-regulatory fatigue: optimism, conscientiousness, and self-consciousness

    OpenAIRE

    Nes, Lise Solberg; Carlson, Charles R.; Crofford, Leslie J.; de Leeuw, Reny; Segerstrom, Suzanne C.

    2011-01-01

    Ability to self-regulate varies and self-regulatory strength is a limited source that can be depleted or fatigued. Research on the impact of individual differences on self-regulatory capacity is still scarce, and this study aimed to examine whether personality factors such as dispositional optimism, conscientiousness, and self-consciousness can impact or buffer self-regulatory fatigue. Participants were patients diagnosed with chronic multi-symptom illnesses (N = 50), or pain free matched con...

  18. LMI optimization approach to stabilization of time-delay chaotic systems

    International Nuclear Information System (INIS)

    Park, Ju H.; Kwon, O.M.

    2005-01-01

    Based on the Lyapunov stability theory and linear matrix inequality (LMI) technique, this paper proposes a novel control method for stabilization of a class of time-delay chaotic systems. A stabilization criterion is derived in terms of LMIs which can be easily solved by efficient convex optimization algorithms. A numerical example is included to show the advantage of the result derived

  19. Effects of Ecohydraulic Bank Stabilization Structures on Bank Stability and Macroinvertebrate Community in Surabaya River

    Directory of Open Access Journals (Sweden)

    Daru Setyo Rini

    2018-01-01

    Full Text Available There were 18 accelerated erosion sites identified along 7 km of Surabaya River Fishery Sanctuary Area. A model of ecohydraulic bank stabilization was applied to reduce bank erosion in Surabaya River at Gresik Regency Indonesia. The model is combination of reprofiled and revegetated bank with rock toe reinforcement and  addition of log groynes. Various native plant species were planted and naturally grown to establish multi-strata littoral vegetation structure. This study assessed effects of ecohydraulic bank stabilization on bank morphology, near bank velocity and littoral macroinvertebrate community during September 2014 to August 2016. The study found that rock toe enforcement, log groynes and reprofiled bank slope could stabilized the eroded bank, and littoral vegetation formation reduced near bank velocity at restored sites. There were 31 families of macroinvertebrate found in Surabaya River with high abundance of moderately pollution sensitive taxa Atyidae and pollution tolerant taxa Corixidae, Chironomidae and Tubificidae. The taxa richness, diversity index and abundance of sensitive and moderately sensitive macroinvertebrate group were increased after application of ecohydraulic bank stabilization at restored area. The results shown that ecohydraulic bank stabilization structure provides multi-benefits in improving bank stabilization against erosion and providing new micro-habitats for biotic community. Keywords:  ecohydraulic bank stabilization, macroinvertebrates, riparian restoration

  20. Community Stabilization and Violence Reduction: Lessons from Darfur

    Directory of Open Access Journals (Sweden)

    Zurab Elzarov

    2015-02-01

    Full Text Available Ravaged by years of conflict and environmental decline, Darfur’s economy has been unable to create sufficient opportunities for youth, creating a link between social instability and high concentration of youth without productive employment. In 2011, the United Nations-African Union Mission in Darfur (UNAMID designed a community stabilization and violence reduction programme to bridge a critical gap between the increasing ‘youth bulge’ and the government's capacity to deliver youth empowerment and job creation solutions to youth in Darfur, leading to militarization of youth. The programme offers vocational skills training and temporary employment of youth through implementation of community-based labour intensive projects (CLIPs. Youth are targeted in particular, since they are an essential part of the solution to resolving the conflict in Darfur. Youth tend to be directly involved in hostilities and are seen to be most likely to return to the battlefield. At the same time, youth are often the community members most open to engaging in post-conflict recovery and peacebuilding activities. Since the conception of the programme in 2011, a total of 58 projects were implemented in 45 communities, and directly targeted over 9,000 youth. In a situation where the peace agreement is non-inclusive and the level of violence against unarmed civilians is high, CLIPs have played an important role in community stabilization and violence reduction in Darfur, building trust, contributing to a secure environment and helping build the foundation for longer term peace and development. As recognition of its contribution to peace and stability in Darfur, in October 2014, UNAMID’s CLIPs programme received the UN 21 Award for Outstanding Vision.

  1. Robust design of decentralized power system stabilizers using meta-heuristic optimization techniques for multimachine systems

    Directory of Open Access Journals (Sweden)

    Jeevanandham Arumugam

    2009-01-01

    Full Text Available In this paper a classical lead-lag power system stabilizer is used for demonstration. The stabilizer parameters are selected in such a manner to damp the rotor oscillations. The problem of selecting the stabilizer parameters is converted to a simple optimization problem with an eigen value based objective function and it is proposed to employ simulated annealing and particle swarm optimization for solving the optimization problem. The objective function allows the selection of the stabilizer parameters to optimally place the closed-loop eigen values in the left hand side of the complex s-plane. The single machine connected to infinite bus system and 10-machine 39-bus system are considered for this study. The effectiveness of the stabilizer tuned using the best technique, in enhancing the stability of power system. Stability is confirmed through eigen value analysis and simulation results and suitable heuristic technique will be selected for the best performance of the system.

  2. Stability and change in forest-based communities: a selected bibliography.

    Science.gov (United States)

    Catherine Woods Richardson

    1996-01-01

    This bibliography lists literature dealing with the concept of community stability, the condition of forest-based communities, and the relations between forest management and local community conditions. Most citations are from the 1970s to the mid 1990s, though some particularly pertinent earlier works also appear. The emphasis is on forest-based communities in the...

  3. SYNTHESIS AND CHARACTERIZATION OF NEW STABILIZERS WITH OPTIMAL MOLECULAR WEIGHT

    Institute of Scientific and Technical Information of China (English)

    Jiang-qing Pan

    2001-01-01

    Over 2 × l08 tons of polymers are produced every year, and a large portion of polymers faces the degradation problem. There are many effective methods to protect polymers against degradation and the addition of stabilizers to polymer remains the most convenient and effective way of enhancing polymer life and performance. In this article, a series of effective stabilizers with optimal molecular weight (MW), including common, monomeric and polymeric stabilizers (antioxidant and light stabilizer) were synthesized using isocyanation, controlled isocyanation, hydrosilylation, epoxide addition, macroreaction of stabilizing functional compounds and polymerization of monomeric stabilizers. The sructure and performance of these new stabilizers were characterized by using IR, NMR, MS, UV-spectra, XPS and elemental analysis. The current development of stabilizer synthesis was also reviewed.``

  4. Optimal Parameter Selection of Power System Stabilizer using Genetic Algorithm

    Energy Technology Data Exchange (ETDEWEB)

    Chung, Hyeng Hwan; Chung, Dong Il; Chung, Mun Kyu [Dong-AUniversity (Korea); Wang, Yong Peel [Canterbury Univeristy (New Zealand)

    1999-06-01

    In this paper, it is suggested that the selection method of optimal parameter of power system stabilizer (PSS) with robustness in low frequency oscillation for power system using real variable elitism genetic algorithm (RVEGA). The optimal parameters were selected in the case of power system stabilizer with one lead compensator, and two lead compensator. Also, the frequency responses characteristics of PSS, the system eigenvalues criterion and the dynamic characteristics were considered in the normal load and the heavy load, which proved usefulness of RVEGA compare with Yu's compensator design theory. (author). 20 refs., 15 figs., 8 tabs.

  5. The long-term stability of self-esteem: its time-dependent decay and nonzero asymptote.

    Science.gov (United States)

    Kuster, Farah; Orth, Ulrich

    2013-05-01

    How stable are individual differences in self-esteem? We examined the time-dependent decay of rank-order stability of self-esteem and tested whether stability asymptotically approaches zero or a nonzero value across long test-retest intervals. Analyses were based on 6 assessments across a 29-year period of a sample of 3,180 individuals aged 14 to 102 years. The results indicated that, as test-retest intervals increased, stability exponentially decayed and asymptotically approached a nonzero value (estimated as .43). The exponential decay function explained a large proportion of variance in observed stability coefficients, provided a better fit than alternative functions, and held across gender and for all age groups from adolescence to old age. Moreover, structural equation modeling of the individual-level data suggested that a perfectly stable trait component underlies stability of self-esteem. The findings suggest that the stability of self-esteem is relatively large, even across very long periods, and that self-esteem is a trait-like characteristic.

  6. Dynamic stability of self-similar solutions for a plasma pinch

    International Nuclear Information System (INIS)

    Ma, Sifeng.

    1988-01-01

    Linear Magnetohydrodynamic (MHD) stability theory is applied to a class of self-similar solutions which describe implosion, expansion and oscillation of an infinitely conducting plasma column. The equations of perturbation are derived in the Lagrangian coordinate system. Numerical procedures via the finite-element method are formulated, and general aspects of dynamic stability are discussed, The dynamic stability of the column when it is oscillatory is studied in detail using the Floquet theory, and the characteristic exponent is calculated numerically. A-pinch configuration is examined. It is found that self-similar oscillations in general destabilize the continua in the MHD spectrum, and parametric instability results

  7. Assessing control of postural stability in community-living older adults using performance-based limits of stability

    DEFF Research Database (Denmark)

    Jbabdi, Myriam; Boissy, Patrice; Hamel, Mathieu

    2008-01-01

    BACKGROUND: Balance disability measurements routinely used to identify fall risks in frail populations have limited value in the early detection of postural stability deficits in community-living older adults. The objectives of the study were to 1) measure performance-based limits of stability (LOS......-session performance variability during multiple trials using the performance-based LOS paradigm. METHODS: Twenty-four healthy community-living older adults (10 men, 14 women) aged between 62 to 85 (mean age +/- sd, 71.5 +/- 6 yrs) participated in the study. Subjects' performance-based LOS were established by asking...

  8. Primary Stability of Self-Drilling and Self-Tapping Mini-Implant in Tibia of Diabetes-Induced Rabbits

    Directory of Open Access Journals (Sweden)

    Jea-Beom Park

    2014-01-01

    Full Text Available Objective. This study aimed to evaluate effects of type 1 diabetes mellitus and mini-implant placement method on the primary stability of mini-implants by comparing mechanical stability and microstructural/histological differences. Methods. After 4 weeks of diabetic induction, 48 mini-implants (24 self-tapping and 24 self-drilling implants were placed on the tibia of 6 diabetic and 6 normal rabbits. After 4 weeks, the rabbits were sacrificed. Insertion torque, removal torque, insertion energy, and removal energy were measured with a surgical engine on 8 rabbits. Remaining 4 rabbits were analyzed by microcomputed tomography (micro-CT and bone histomorphometry. Results. Total insertion energy was higher in self-drilling groups than self-tapping groups in both control and diabetic groups. Diabetic groups had more trabecular separation in bone marrow than the control groups in both SD and ST groups. Micro-CT analysis showed deterioration of bone quality in tibia especially in bone marrow of diabetic rabbits. However, there was no statistically significant correlation between self-drilling and self-tapping group for the remaining measurements in both control and diabetic groups. Conclusions. Type 1 diabetes mellitus and placement method of mini-implant did not affect primary stability of mini-implants.

  9. Conceptual Design Optimization of an Augmented Stability Aircraft Incorporating Dynamic Response Performance Constraints

    Science.gov (United States)

    Welstead, Jason

    2014-01-01

    This research focused on incorporating stability and control into a multidisciplinary de- sign optimization on a Boeing 737-class advanced concept called the D8.2b. A new method of evaluating the aircraft handling performance using quantitative evaluation of the sys- tem to disturbances, including perturbations, continuous turbulence, and discrete gusts, is presented. A multidisciplinary design optimization was performed using the D8.2b transport air- craft concept. The con guration was optimized for minimum fuel burn using a design range of 3,000 nautical miles. Optimization cases were run using xed tail volume coecients, static trim constraints, and static trim and dynamic response constraints. A Cessna 182T model was used to test the various dynamic analysis components, ensuring the analysis was behaving as expected. Results of the optimizations show that including stability and con- trol in the design process drastically alters the optimal design, indicating that stability and control should be included in conceptual design to avoid system level penalties later in the design process.

  10. PI Stabilization for Congestion Control of AQM Routers with Tuning Parameter Optimization

    Directory of Open Access Journals (Sweden)

    S. Chebli

    2016-09-01

    Full Text Available In this paper, we consider the problem of stabilizing network using a new proportional- integral (PI based congestion controller in active queue management (AQM router; with appropriate model approximation in the first order delay systems, we seek a stability region of the controller by using the Hermite- Biehler theorem, which isapplicable to quasipolynomials. A Genetic Algorithm technique is employed to derive optimal or near optimal PI controller parameters.

  11. Optimized Extreme Learning Machine for Power System Transient Stability Prediction Using Synchrophasors

    Directory of Open Access Journals (Sweden)

    Yanjun Zhang

    2015-01-01

    Full Text Available A new optimized extreme learning machine- (ELM- based method for power system transient stability prediction (TSP using synchrophasors is presented in this paper. First, the input features symbolizing the transient stability of power systems are extracted from synchronized measurements. Then, an ELM classifier is employed to build the TSP model. And finally, the optimal parameters of the model are optimized by using the improved particle swarm optimization (IPSO algorithm. The novelty of the proposal is in the fact that it improves the prediction performance of the ELM-based TSP model by using IPSO to optimize the parameters of the model with synchrophasors. And finally, based on the test results on both IEEE 39-bus system and a large-scale real power system, the correctness and validity of the presented approach are verified.

  12. Place, health, and community attachment: Is community capacity associated with self-rated health at the individual level?

    Science.gov (United States)

    Lovell, Sarah A; Gray, Andrew R; Boucher, Sara E

    2017-12-01

    Community-level interventions dominate contemporary public health responses to health inequalities as a lack of political will has discouraged action at a structural level. Health promoters commonly leverage community capacity to achieve programme goals, yet the health implications of low community capacity are unknown. In this study, we analyse perceptions of community capacity at the individual-level to explore how place-based understandings of identity and connectedness are associated with self-rated health. We examine associations between individual community capacity, self-rated health and income using a cross-sectional survey that was disseminated to 303 residents of four small (populations 1500-2000) New Zealand towns. Evidence indicating a relationship between individual community capacity and self-reported health was unconvincing once the effects of income were incorporated. That is, people who rated their community's capacity higher did not have better self-rated health. Much stronger evidence supported the relationship between income and both higher individual community capacity and higher self-rated health. We conclude that individual community capacity may mediate the positive association between income and health, however, overall we find no evidence suggesting that intervening to enhance individual community capacity is likely to improve health outcomes.

  13. Self-esteem stability and depressive symptoms in acute stroke rehabilitation: methodological and conceptual expansion.

    Science.gov (United States)

    Vickery, Chad D; Evans, Clea C; Sepehri, Arash; Jabeen, Linsa N; Gayden, Monee

    2009-08-01

    Explore the relationship of self-esteem level, self-esteem stability, and other moderating variables with depressive symptoms in acute stroke rehabilitation. One hundred twenty participants completed measures of state self-esteem, perceived recovery, hospitalization-based hassles, impairment-related distress, and tendency to overgeneralize negative self-connotations of bad events. Self-report of depressive symptoms was collected at admission and on discharge. Four regression analyses explored the relationship of self-esteem level and stability and each of 4 moderating variables (perceived recovery, hassles, impairment-related distress, and overgeneralization) with depressive symptoms at discharge. Analyses indicated significant 3-way interactions in the 4 regression models. In general, individuals with unstable high self-esteem endorsed greater depressive symptoms under conditions of vulnerability (e.g., lower perceived recovery) than did individuals with stable high self-esteem. Under conditions of vulnerability, participants with stable low self-esteem indicated the highest levels of depressive symptoms. Self-esteem level and stability interact with psychological, environmental, and stroke-specific variables to predict depressive symptoms at discharge from stroke rehabilitation. This suggests the viability of self-esteem stability in exploring depressive symptoms in this setting and the complexity of emotional adjustment early after stroke. (c) 2009 APA

  14. Self-optimizing robust nonlinear model predictive control

    NARCIS (Netherlands)

    Lazar, M.; Heemels, W.P.M.H.; Jokic, A.; Thoma, M.; Allgöwer, F.; Morari, M.

    2009-01-01

    This paper presents a novel method for designing robust MPC schemes that are self-optimizing in terms of disturbance attenuation. The method employs convex control Lyapunov functions and disturbance bounds to optimize robustness of the closed-loop system on-line, at each sampling instant - a unique

  15. Optimization of VCSELs for Self-Mixing Sensing

    DEFF Research Database (Denmark)

    Larsson, David; Yvind, Kresten; Chung, Il-Sug

    2010-01-01

    We have simulated the variations in optical output power from a vertical-cavity surface-emitting laser (VCSEL) subject to self-mixing feedback, which is very important for applications in sensing. In order to maximize the self-mixing signal for a given feedback we have optimized the epitaxial...

  16. Robust Optimization-Based Generation Self-Scheduling under Uncertain Price

    Directory of Open Access Journals (Sweden)

    Xiao Luo

    2011-01-01

    Full Text Available This paper considers generation self-scheduling in electricity markets under uncertain price. Based on the robust optimization (denoted as RO methodology, a new self-scheduling model, which has a complicated max-min optimization structure, is set up. By using optimal dual theory, the proposed model is reformulated to an ordinary quadratic and quadratic cone programming problems in the cases of box and ellipsoidal uncertainty, respectively. IEEE 30-bus system is used to test the new model. Some comparisons with other methods are done, and the sensitivity with respect to the uncertain set is analyzed. Comparing with the existed uncertain self-scheduling approaches, the new method has twofold characteristics. First, it does not need a prediction of distribution of random variables and just requires an estimated value and the uncertain set of power price. Second, the counterpart of RO corresponding to the self-scheduling is a simple quadratic or quadratic cone programming. This indicates that the reformulated problem can be solved by many ordinary optimization algorithms.

  17. Conceptualizing and measuring illness self-concept: a comparison with self-esteem and optimism in predicting fibromyalgia adjustment.

    Science.gov (United States)

    Morea, Jessica M; Friend, Ronald; Bennett, Robert M

    2008-12-01

    Illness self-concept (ISC), or the extent to which individuals are consumed by their illness, was theoretically described and evaluated with the Illness Self-Concept Scale (ISCS), a new 23-item scale, to predict adjustment in fibromyalgia. To establish convergent and discriminant validity, illness self-concept was compared to self-esteem and optimism in predicting health status, illness intrusiveness, depression, and life satisfaction. The ISCS demonstrated good reliability (alpha = .94; test-retest r = .80) and was a strong predictor of outcomes, even after controlling for optimism or self-esteem. The ISCS predicted unique variance in health-related outcomes; optimism and self-esteem did not, providing construct validation. Illness self-concept may play a significant role in coping with fibromyalgia and may prove useful in the evaluation of other chronic illnesses. (c) 2008 Wiley Periodicals, Inc.

  18. Optimization on Fc for Improvement of Stability and Aggregation Resistance.

    Science.gov (United States)

    Chen, Xiaobo; Zeng, Fang; Huang, Tao; Cheng, Liang; Liu, Huan; Gong, Rui

    2016-01-01

    Fc-based therapeutics including therapeutic full-size monoclonal antibodies (mAbs) and Fcfusion proteins represent fastest-growing market in biopharmaceutical industrial. However, one major challenge during development of Fc-based therapeutics is how to maintain their efficacy in clinic use. Many factors may lead to failure in final marketing. For example, the stability and aggregation resistance might not be high enough for bearing the disadvantages during fermentation, purification, formulation, storage, shipment and other steps in manufacture and sale. Low stability and high aggregation tendency lead to decreased bioactivity and increased risk of immunogenicity resulting in serious side effect. Because Fc is one of the major parts in monoclonal antibodies and Fc-fusion proteins, engineering of Fc to increase its stability and reduce or eliminate aggregation due to incorrect association are of great importance and could further extend the potential of Fc-based therapeutics. Lots of studies focus on Fc optimization for better physical and chemical characteristics and function by structured-based computer-aid rational design, high-throughput screening expression system selection and other methods. The identification of optimized Fc mutants increases the clinic potential of currently existed therapeutics mAbs and Fc-fusion proteins, and accelerates the development of new Fc-based therapeutics. Here we provide an overview of the related field, and discuss recent advances and future directions in optimization of Fc-based therapeutics with modified stability and aggregation resistance. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

  19. Place, health, and community attachment: Is community capacity associated with self-rated health at the individual level?

    Directory of Open Access Journals (Sweden)

    Sarah A. Lovell

    2017-12-01

    Full Text Available Community-level interventions dominate contemporary public health responses to health inequalities as a lack of political will has discouraged action at a structural level. Health promoters commonly leverage community capacity to achieve programme goals, yet the health implications of low community capacity are unknown. In this study, we analyse perceptions of community capacity at the individual-level to explore how place-based understandings of identity and connectedness are associated with self-rated health. We examine associations between individual community capacity, self-rated health and income using a cross-sectional survey that was disseminated to 303 residents of four small (populations 1500–2000 New Zealand towns. Evidence indicating a relationship between individual community capacity and self-reported health was unconvincing once the effects of income were incorporated. That is, people who rated their community's capacity higher did not have better self-rated health. Much stronger evidence supported the relationship between income and both higher individual community capacity and higher self-rated health. We conclude that individual community capacity may mediate the positive association between income and health, however, overall we find no evidence suggesting that intervening to enhance individual community capacity is likely to improve health outcomes.

  20. Achieving Optimal Self-Adaptivity for Dynamic Tuning of Organic Semiconductors through Resonance Engineering.

    Science.gov (United States)

    Tao, Ye; Xu, Lijia; Zhang, Zhen; Chen, Runfeng; Li, Huanhuan; Xu, Hui; Zheng, Chao; Huang, Wei

    2016-08-03

    Current static-state explorations of organic semiconductors for optimal material properties and device performance are hindered by limited insights into the dynamically changed molecular states and charge transport and energy transfer processes upon device operation. Here, we propose a simple yet successful strategy, resonance variation-based dynamic adaptation (RVDA), to realize optimized self-adaptive properties in donor-resonance-acceptor molecules by engineering the resonance variation for dynamic tuning of organic semiconductors. Organic light-emitting diodes hosted by these RVDA materials exhibit remarkably high performance, with external quantum efficiencies up to 21.7% and favorable device stability. Our approach, which supports simultaneous realization of dynamically adapted and selectively enhanced properties via resonance engineering, illustrates a feasible design map for the preparation of smart organic semiconductors capable of dynamic structure and property modulations, promoting the studies of organic electronics from static to dynamic.

  1. Purpose-driven public sector reform: the need for within-government capacity build for the management of slope stability in communities in the Caribbean.

    Science.gov (United States)

    Anderson, Malcolm; Holcombe, Liz

    2006-01-01

    This article stresses the importance of within-government capacity build as the optimal approach to minimizing landslide risk to the most vulnerable communities in the developing world. Landslide risk is an integrated issue that demands strong managerial leadership and multidisciplinary inclusion to develop structures that deliver sustainable improvements in the reduction of risk. The tension between projects demanding international technical and financial intervention and those capable of "within-country" solutions are examined. More particularly, the challenges of developing a management methodology capable of energizing inter-ministry collaboration to achieve community-level action is examined in the context of a recently established program of slope stability management in St. Lucia. The program, Management of Slope Stability in Communities (MoSSaiC), is shown to have successfully fostered not only extensive technical collaboration within government but also to have energized local communities in the shared mission of capacity build through their direct involvement in the management process.

  2. Natural shorelines promote the stability of fish communities in an urbanized coastal system.

    Directory of Open Access Journals (Sweden)

    Steven B Scyphers

    Full Text Available Habitat loss and fragmentation are leading causes of species extinctions in terrestrial, aquatic and marine systems. Along coastlines, natural habitats support high biodiversity and valuable ecosystem services but are often replaced with engineered structures for coastal protection or erosion control. We coupled high-resolution shoreline condition data with an eleven-year time series of fish community structure to examine how coastal protection structures impact community stability. Our analyses revealed that the most stable fish communities were nearest natural shorelines. Structurally complex engineered shorelines appeared to promote greater stability than simpler alternatives as communities nearest vertical walls, which are among the most prevalent structures, were most dissimilar from natural shorelines and had the lowest stability. We conclude that conserving and restoring natural habitats is essential for promoting ecological stability. However, in scenarios when natural habitats are not viable, engineered landscapes designed to mimic the complexity of natural habitats may provide similar ecological functions.

  3. [The optimization of a surgical intervention to stabilize progressive myopia].

    Science.gov (United States)

    Gonchar, P A; Dushin, N V; Beliaev, V S; Kravchinina, V V; Barashkov, V I; Frolov, M A

    1999-01-01

    Results of 236 sclera-fortifying surgeries are followed up for more than 25 years. Progressive myopia stabilized in 95.8% cases after bandaging scleroplasty and in 87.03% cases after chondroplasty. Clinical refraction and posteroanterior axis of the eye did not increase after surgery; visual functions stabilized, and brightness sensitivity threshold was lowered. The technique of operation and clinical course of the postoperative period are described. Based on analysis of the clinical material, the authors propose the optimal approach to scleroplastic operations aimed at stabilization of progressive myopia.

  4. Structural Design Optimization of a Tiltrotor Aircraft Composite Wing to Enhance Whirl Flutter Stability

    DEFF Research Database (Denmark)

    Kim, Taeseong; Kim, Jaehoon; Shin, Sang Joon

    2013-01-01

    In order to enhance the aeroelastic stability of a tiltrotor aircraft, a structural optimization framework is developed by applying a multi-level optimization approach. Each optimization level is designed to achieve a different purpose; therefore, relevant optimization schemes are selected for each...... level. Enhancement of the aeroelastic stability is selected as an objective in the upper-level optimization. This is achieved by seeking the optimal structural properties of a composite wing, including its mass, vertical, chordwise, and torsional stiffness. In the upper-level optimization, the response...... surface method (RSM), is selected. On the other hand, lower-level optimization seeks to determine the local detailed cross-sectional parameters, such as the ply orientation angles and ply thickness, which are relevant to the wing structural properties obtained at the upper-level. To avoid manufacturing...

  5. Self-esteem stability in relation to narcissism and psychological well-being

    OpenAIRE

    Saša Zorjan; Katja Košir

    2013-01-01

    The concept of self-esteem stability has an important role in the understanding of interpersonal and psychological functioning of individuals. The purpose of this study was to examine the relationship between self-esteem stability, narcissism and psychological well-being. A total of 178 participants (77% female) participated in this study. The average age of the participants was 20, with the ages ranging from 18 to 26 years. The participants completed the following scales and questionnaires: ...

  6. Family factors of self-esteem stability in adolescents

    Directory of Open Access Journals (Sweden)

    Todorović Jelisaveta A.

    2005-01-01

    Full Text Available The aim of investigations was to examine what upbringing styles and socio-economic parameters correlate with adolescents’ unstable self-esteem. Self-esteem is an evaluative measure of self-concept whose stability in time reflects personality’s autonomy and integrity. Using the sample of 280 secondary school students, the SSES scale was administered twice, at a 30-day interval, the EMBU scale of upbringing styles, a questionnaire with general data on respondents and socioeconomic parameters. It proved that upbringing style and parental tenderness (of both father and mother correlate with unstable self-esteem in adolescents. Significant correlation between upbringing styles and unstable self-esteem was also found in inconsistency, low control and protection on the part of father. Stable self-esteem is significantly negatively correlated with inconsistency of mother. Of diverse socioeconomic parameters, educational level of father and his profession are of critical importance for stable self-esteem. Upbringing styles produce greater influence on self-esteem level than socio-economic parameters do.

  7. Why 'Optimal' Payment for Healthcare Providers Can Never be Optimal Under Community Rating.

    Science.gov (United States)

    Zweifel, Peter; Frech, H E

    2016-02-01

    This article extends the existing literature on optimal provider payment by accounting for consumer heterogeneity in preferences for health insurance and healthcare. This heterogeneity breaks down the separation of the relationship between providers and the health insurer and the relationship between consumers and the insurer. Both experimental and market evidence for a high degree of heterogeneity are presented. Given heterogeneity, a uniform policy fails to effectively control moral hazard, while incentives for risk selection created by community rating cannot be neutralized through risk adjustment. Consumer heterogeneity spills over into relationships with providers, such that a uniform contract with providers also cannot be optimal. The decisive condition for ensuring optimality of provider payment is to replace community rating (which violates the principle of marginal cost pricing) with risk rating of contributions combined with subsidization targeted at high risks with low incomes.

  8. Stabilization of Hypersonic Boundary Layers by Linear and Nonlinear Optimal Perturbations

    Science.gov (United States)

    Paredes, Pedro; Choudhari, Meelan M.; Li, Fei

    2017-01-01

    The effect of stationary, finite-amplitude, linear and nonlinear optimal perturbations on the modal disturbance growth in a Mach 6 axisymmetric flow over a 7 deg. half-angle cone with 0:126 mm nose radius and 0:305 m length is investigated. The freestream parameters (M = 6, Re(exp 1) = 18 x 10(exp. 6) /m) are selected to match the flow conditions of a previous experiment in the VKI H3 hypersonic tunnel. Plane-marching parabolized stability equations are used in conjunction with a partial-differential equation based planar eigenvalue analysis to characterize the boundary layer instability in the presence of azimuthally periodic streaks. The streaks are observed to stabilize nominally planar Mack mode instabilities, although oblique Mack mode and first-mode disturbances are destabilized. Experimentally measured transition onset in the absence of any streaks correlates with an amplification factor of N = 6 for the planar Mack modes. For high enough streak amplitudes, the transition threshold of N = 6 is not reached by the Mack mode instabilities within the length of the cone; however, subharmonic first-mode instabilities, which are destabilized by the presence of the streaks, do reach N = 6 near the end of the cone. The highest stabilization is observed at streak amplitudes of approximately 20 percent of the freestream velocity. Because the use of initial disturbance profiles based on linear optimal growth theory may yield suboptimal control in the context of nonlinear streaks, the computational predictions are extended to nonlinear optimal growth theory. Results show that by using nonlinearly optimal perturbation leads to slightly enhanced stabilization of plane Mack mode disturbances as well as reduced destabilization of subharmonic first-mode disturbances.

  9. Comparative evaluation of insertion torque and mechanical stability for self-tapping and self-drilling orthodontic miniscrews - an in vitro study.

    Science.gov (United States)

    Tepedino, Michele; Masedu, Francesco; Chimenti, Claudio

    2017-05-30

    The aim of the present study was to evaluate the relationship between insertion torque and stability of miniscrews in terms of resistance against dislocation, then comparing a self-tapping screw with a self-drilling one. Insertion torque was measured during placement of 30 self-drilling and 31 self-tapping stainless steel miniscrews (Leone SpA, Sesto Fiorentino, Italy) in synthetic bone blocks. Then, an increasing pulling force was applied at an angle of 90° and 45°, and the displacement of the miniscrews was recorded. The statistical analysis showed a statistically significant difference between the mean Maximum Insertion Torque (MIT) observed in the two groups and showed that force angulation and MIT have a statistically significant effect on miniscrews stability. For both the miniscrews, an angle of 90° between miniscrew and loading force is preferable in terms of stability. The tested self-drilling orthodontic miniscrews showed higher MIT and greater resistance against dislocation than the self-tapping ones.

  10. Stability-index based method for optimal Var planning in distribution feeders

    International Nuclear Information System (INIS)

    Hamouda, Abdellatif; Zehar, Khaled

    2011-01-01

    Research highlights: → Optimal Var planning is modelled using heuristic methods. → Capacitor sizes and location are determined by a two stage method. → Capacitor locations are determined using nodes stability-indices. → Their sizes are calculated subject to a new constraint on the branches reactive currents. → The solution is fast and leads to better results without over compensation. -- Abstract: The problem of the reactive energy optimal planning can be solved in a fast and efficient way using heuristic techniques. The latter reduce the number of the control variables to be determined and lead to a near global optimal solution. The capacitor appropriate locations are firstly determined by decisive indices then, their optimal sizes are calculated. In this paper a stability-index based method is presented. The nodes stability-indices are calculated for identifying the most sensitive nodes to be candidate for receiving near optimal standard capacitors that, reduce the feeder power losses, improve the voltage profile and maximise the economic saving (objective function). In this multi-objective optimisation problem, the commonly used voltage constraint is substituted by a new constraint on the branch reactive currents. This new constraint, allows overcoming the over compensation phenomenon by setting positive branch reactive currents. The solution is further improved by regulating the source node voltage. The proposed approach has been tested on several feeder examples and its effectiveness has been demonstrated through comparative studies. The obtained results have shown that the proposed approach leads to a promising and feasible solution.

  11. Stability-index based method for optimal Var planning in distribution feeders

    Energy Technology Data Exchange (ETDEWEB)

    Hamouda, Abdellatif, E-mail: a_hamouda1@yahoo.f [QUERE Laboratory, Optics and Mechanics Institut, University Ferhat Abbas, Setif 19000 (Algeria); Zehar, Khaled [QUERE Laboratory, Department of Electrical and Electronics Engineering, University of Bahrain, Isa Town (Bahrain)

    2011-05-15

    Research highlights: {yields} Optimal Var planning is modelled using heuristic methods. {yields} Capacitor sizes and location are determined by a two stage method. {yields} Capacitor locations are determined using nodes stability-indices. {yields} Their sizes are calculated subject to a new constraint on the branches reactive currents. {yields} The solution is fast and leads to better results without over compensation. -- Abstract: The problem of the reactive energy optimal planning can be solved in a fast and efficient way using heuristic techniques. The latter reduce the number of the control variables to be determined and lead to a near global optimal solution. The capacitor appropriate locations are firstly determined by decisive indices then, their optimal sizes are calculated. In this paper a stability-index based method is presented. The nodes stability-indices are calculated for identifying the most sensitive nodes to be candidate for receiving near optimal standard capacitors that, reduce the feeder power losses, improve the voltage profile and maximise the economic saving (objective function). In this multi-objective optimisation problem, the commonly used voltage constraint is substituted by a new constraint on the branch reactive currents. This new constraint, allows overcoming the over compensation phenomenon by setting positive branch reactive currents. The solution is further improved by regulating the source node voltage. The proposed approach has been tested on several feeder examples and its effectiveness has been demonstrated through comparative studies. The obtained results have shown that the proposed approach leads to a promising and feasible solution.

  12. Computing Fault-Containment Times of Self-Stabilizing Algorithms Using Lumped Markov Chains

    Directory of Open Access Journals (Sweden)

    Volker Turau

    2018-05-01

    Full Text Available The analysis of self-stabilizing algorithms is often limited to the worst case stabilization time starting from an arbitrary state, i.e., a state resulting from a sequence of faults. Considering the fact that these algorithms are intended to provide fault tolerance in the long run, this is not the most relevant metric. A common situation is that a running system is an a legitimate state when hit by a single fault. This event has a much higher probability than multiple concurrent faults. Therefore, the worst case time to recover from a single fault is more relevant than the recovery time from a large number of faults. This paper presents techniques to derive upper bounds for the mean time to recover from a single fault for self-stabilizing algorithms based on Markov chains in combination with lumping. To illustrate the applicability of the techniques they are applied to a new self-stabilizing coloring algorithm.

  13. Nonsuicidal Self-Harm among Community Adolescents: Understanding the "Whats" and "Whys" of Self-Harm

    Science.gov (United States)

    Laye-Gindhu, Aviva; Schonert-Reichl, Kimberly A.

    2005-01-01

    This study examines self-harm in a community sample of adolescents. More specifically, the study identifies the prevalence and types of self-harm, elucidates the nature and underlying function of self-harm, and evaluates the relation of psychological adjustment, sociodemographic, and health-risk variables to self-harm. Self-report questionnaires…

  14. Self-Esteem and Feelings of Community Connectedness of At-Risk Adolescents Attending Community-Based Afterschool Programs

    Directory of Open Access Journals (Sweden)

    Tina Loughlin

    2013-03-01

    Full Text Available This research investigated the relationship between adolescent afterschool program attendance, self-esteem and feelings of community connectedness. Thirty-nine of the 61 at-risk adolescents enrolled in two federally funded, community based afterschool programs participated in the study. Participants completed a 10-item self-esteem questionnaire and a 5-item section of the Youth Involved in Community Issues Survey (YICI to measure perceptions of community connectedness. Attendance records were also collected from the sites. Data were analyzed using Pearson Correlations. Results indicated that there was not a significant relationship between the total variables. The individual item analysis, however, did find a significant relationship between adolescent community connectedness and self esteem items. Findings suggest that there is a relationship to be explored and strengthened through means of community outreach for adolescents. Conclusions from this study have important implications for youth practice. Specifically, program leaders need to help adolescents get involved in the community as contributing members.

  15. Phytoplankton Biogeography and Community Stability in the Ocean

    Science.gov (United States)

    Cermeño, Pedro; de Vargas, Colomban; Abrantes, Fátima; Falkowski, Paul G.

    2010-01-01

    Background Despite enormous environmental variability linked to glacial/interglacial climates of the Pleistocene, we have recently shown that marine diatom communities evolved slowly through gradual changes over the past 1.5 million years. Identifying the causes of this ecological stability is key for understanding the mechanisms that control the tempo and mode of community evolution. Methodology/Principal Findings If community assembly were controlled by local environmental selection rather than dispersal, environmental perturbations would change community composition, yet, this could revert once environmental conditions returned to previous-like states. We analyzed phytoplankton community composition across >104 km latitudinal transects in the Atlantic Ocean and show that local environmental selection of broadly dispersed species primarily controls community structure. Consistent with these results, three independent fossil records of marine diatoms over the past 250,000 years show cycles of community departure and recovery tightly synchronized with the temporal variations in Earth's climate. Conclusions/Significance Changes in habitat conditions dramatically alter community structure, yet, we conclude that the high dispersal of marine planktonic microbes erases the legacy of past environmental conditions, thereby decreasing the tempo of community evolution. PMID:20368810

  16. Optimizing Tube Precurvature to Enhance Elastic Stability of Concentric Tube Robots.

    Science.gov (United States)

    Ha, Junhyoung; Park, Frank C; Dupont, Pierre E

    2017-02-01

    Robotic instruments based on concentric tube technology are well suited to minimally invasive surgery since they are slender, can navigate inside small cavities and can reach around sensitive tissues by taking on shapes of varying curvature. Elastic instabilities can arise, however, when rotating one precurved tube inside another. In contrast to prior work that considered only tubes of piecewise constant precurvature, we allow precurvature to vary along the tube's arc length. Stability conditions for a planar tube pair are derived and used to formulate an optimal design problem. An analytic formulation of the optimal precurvature function is derived that achieves a desired tip orientation range while maximizing stability and respecting bending strain limits. This formulation also includes straight transmission segments at the proximal ends of the tubes. The result, confirmed by both numerical and physical experiment, enables designs with enhanced stability in comparison to designs of constant precurvature.

  17. Self-esteem level and stability, admission functional status, and depressive symptoms in acute inpatient stroke rehabilitation.

    Science.gov (United States)

    Vickery, Chad D; Sepehri, Arash; Evans, Clea C; Jabeen, Linsa N

    2009-11-01

    Explore the relationship of self-esteem level, self-esteem stability, and admission functional status on discharge depressive symptoms in acute stroke rehabilitation. One hundred twenty stroke survivors serially completed a measure of state self-esteem during inpatient rehabilitation and completed a measure of depressive symptoms at discharge. Functional status was rated at admission using the Functional Independence Measure (FIM). Regressions explored main effects and interactions of self-esteem level and stability and admission FIM self-care, mobility, and cognitive functioning on discharge depressive symptoms. After controlling for potential moderating variables, self-esteem level interacted with FIM self-care and cognitive functioning to predict discharge depressive symptoms, such that survivors with lower self-rated self-esteem and poorer functional status indicated higher levels of depressive symptoms. Self-esteem stability interacted with FIM mobility functioning, such that self-esteem instability in the presence of lower mobility functioning at admission was related to higher depressive symptoms at discharge. These results suggest that self-esteem variables may moderate the relationship between functional status and depressive symptoms. Self-esteem level and stability may differentially moderate functional domains, although this conclusion requires further empirical support.

  18. Formulation, optimization, and evaluation of self-emulsifying drug delivery systems of nevirapine.

    Science.gov (United States)

    Chintalapudi, Ramprasad; Murthy, T E G K; Lakshmi, K Rajya; Manohar, G Ganesh

    2015-01-01

    The aim of the present study was to formulate and optimize the self-emulsifying drug delivery systems (SEDDS) of nevirapine (NVP) by use of 2(2) factorial designs to enhance the oral absorption of NVP by improving its solubility, dissolution rate, and diffusion profile. SEDDS are the isotropic mixtures of oil, surfactant, co-surfactant and drug that form oil in water microemulsion when introduced into the aqueous phase under gentle agitation. Solubility of NVP in different oils, surfactants, and co-surfactants was determined for the screening of excipients. Pseudo-ternary phase diagrams were constructed by the aqueous titration method, and formulations were developed based on the optimum excipient combinations with the help of data obtained through the maximum micro emulsion region containing combinations of oil, surfactant, and co-surfactant. The formulations of SEDDS were optimized by 2(2) factorial designs. The optimum formulation of SEDDS contains 32.5% oleic acid, 44.16% tween 20, and 11.9% polyethylene glycol 600 as oil, surfactant, and co-surfactant respectively. The SEDDS was evaluated for the following drug content, self-emulsification time, rheological properties, zeta potential, in vitro diffusion studies, thermodynamic stability studies, and in vitro dissolution studies. An increase in dissolution was achieved by SEDDS compared to pure form of NVP. Overall, this study suggests that the dissolution and oral bioavailability of NVP could be improved by SEDDS technology.

  19. Optimal design of RTCs in digital circuit fault self-repair based on global signal optimization

    Institute of Scientific and Technical Information of China (English)

    Zhang Junbin; Cai Jinyan; Meng Yafeng

    2016-01-01

    Since digital circuits have been widely and thoroughly applied in various fields, electronic systems are increasingly more complicated and require greater reliability. Faults may occur in elec-tronic systems in complicated environments. If immediate field repairs are not made on the faults, elec-tronic systems will not run normally, and this will lead to serious losses. The traditional method for improving system reliability based on redundant fault-tolerant technique has been unable to meet the requirements. Therefore, on the basis of (evolvable hardware)-based and (reparation balance technology)-based electronic circuit fault self-repair strategy proposed in our preliminary work, the optimal design of rectification circuits (RTCs) in electronic circuit fault self-repair based on global sig-nal optimization is deeply researched in this paper. First of all, the basic theory of RTC optimal design based on global signal optimization is proposed. Secondly, relevant considerations and suitable ranges are analyzed. Then, the basic flow of RTC optimal design is researched. Eventually, a typical circuit is selected for simulation verification, and detailed simulated analysis is made on five circumstances that occur during RTC evolution. The simulation results prove that compared with the conventional design method based RTC, the global signal optimization design method based RTC is lower in hardware cost, faster in circuit evolution, higher in convergent precision, and higher in circuit evolution success rate. Therefore, the global signal optimization based RTC optimal design method applied in the elec-tronic circuit fault self-repair technology is proven to be feasible, effective, and advantageous.

  20. Communities, self-causation and the natural lottery.

    Science.gov (United States)

    Loewy, E H

    1988-01-01

    This paper examines the various notions of community, and of the 'natural lottery' as well as investigating the role that 'self-causation' plays in communal obligations. In examining community, two opposing views are juxtaposed: (1) the view that community consists merely of persons united by duties of refraining from harm one to another, resulting in autonomy based justice which makes freedom an absolute condition of mortality; and (2) a broader view which sees the concept of community as entailing obligations of beneficence, resulting in beneficence based justice and which, therefore, sees freedom as a value to be cautiously traded with other values. In examining the 'natural lottery' in the light of community, the various consequences of viewing the lottery in various ways and the impact that our view of community has on these consequences, is explored. A third option, the option that the 'natural lottery' as the cause of illness and health is a shaky concept, is offered. Self-causation of illness and its linkage to concepts of community and of the 'natural lottery' is then briefly examined. It is concluded that (1) community implies a social contract which, in order to be conceived in the first place, necessitates more than a minimalist ethic: to come about, a degree of beneficence inspiring trust is presupposed; (2) conceiving community narrowly is neither what we ordinarily do when we think of the term nor, for that matter, workable in our world.(ABSTRACT TRUNCATED AT 250 WORDS)

  1. Optimal Sliding Mode Controllers for Attitude Stabilization of Flexible Spacecraft

    Directory of Open Access Journals (Sweden)

    Chutiphon Pukdeboon

    2011-01-01

    Full Text Available The robust optimal attitude control problem for a flexible spacecraft is considered. Two optimal sliding mode control laws that ensure the exponential convergence of the attitude control system are developed. Integral sliding mode control (ISMC is applied to combine the first-order sliding mode with optimal control and is used to control quaternion-based spacecraft attitude manoeuvres with external disturbances and an uncertainty inertia matrix. For the optimal control part the state-dependent Riccati equation (SDRE and optimal Lyapunov techniques are employed to solve the infinite-time nonlinear optimal control problem. The second method of Lyapunov is used to guarantee the stability of the attitude control system under the action of the proposed control laws. An example of multiaxial attitude manoeuvres is presented and simulation results are included to verify the usefulness of the developed controllers.

  2. Analysis of stability to cheaters in models of antibiotic degrading microbial communities.

    Science.gov (United States)

    Szilágyi, András; Boza, Gergely; Scheuring, István

    2017-06-21

    Antibiotic resistance carried out by antibiotic degradation has been suggested recently as a new mechanism to maintain coexistence of microbial species competing on a single limiting resource, even in well-mixed homogeneous environments. Species diversity and community stability, however, critically depend on resistance against social cheaters, mutants that do not invest in production, but still enjoy the benefits provided by others. Here we investigate how different mutant cheaters affect the stability of antibiotic producing and degrading microbial communities. We consider two cheater types, production and degradation cheaters. We generalize the mixed inhibition-zone and chemostat models introduced previously [Kelsic, E. D., Zhao, J., Vetsigian, K., Kishony, R., 2015. Counteraction of an tibiotic production and degradation stabilizes microbial communities. Nature521, 516-519.] to study the population dynamics of microbial communities in well-mixed environment, and analyze the invasion of different cheaters in these models. We show that production cheaters, mutants that cease producing antibiotics, always destroy coexistence whenever there is a cost of producing these antibiotics. Degradation cheaters, mutants that loose their function of producing extracellular antibiotic degrading molecules, induce community collapse only if the cost of producing the degradation factors is above a critical level. Our analytical studies, supported by numerical simulations, highlight the sensitivity of antibiotic producing and degrading communities to loss-of-function mutants. Copyright © 2017 Elsevier Ltd. All rights reserved.

  3. Design of Simulation Product for Stability of Electric Power System Using Power System Stabilizer and Optimal Control

    Science.gov (United States)

    Junaidi, Agus; Hamid, K. Abdul

    2018-03-01

    This paper will discuss the use of optimal control and Power System Stabilizer (PSS) in improving the oscillation of electric power system. Oscillations in the electric power system can occur due to the sudden release of the load (Switcing-Off). The oscillation of an unstable system for a long time causes the equipment to work in an interruption. To overcome this problem, a control device is required that can work effectively in repairing the oscillation. The power system is modeled from the Single Machine Infinite Bus Model (SMIB). The state space equation is used to mathematically model SMIB. SMIB system which is a plant will be formed togetherness state variables (State-Space), using riccati equation then determined the optimal gain as controller plant. Plant is also controlled by Power Stabilizer System using phase compensation method. Using Matlab Software based simulation will be observed response of rotor speed change and rotor angle change for each of the two controlling methods. Simulation results using the Simulink-MATLAB 6.1 software will compare the analysis of the plant state in Open loop state and use the controller. The simulation response shows that the optimal control and PSS can improve the stability of the power system in terms of acceleration to achieve settling-time and Over Shoot improvement. From the results of both methods are able to improve system performance.

  4. Stability of Parental Nurturance as a Salient Predictor of Self-Esteem.

    Science.gov (United States)

    Buri, John R.

    In the recent past there has been a growing interest in the investigation of the self. A primary area of investigation has revolved around the question of the stability of the self-concept. This study investigated parental nurturance as a stable predictor of self-esteem across adolescent and young adult age groups. Subjects (N=784) were students…

  5. Does functional redundancy stabilize fish communities?

    DEFF Research Database (Denmark)

    Rice, Jake; Daan, Niels; Gislason, Henrik

    2013-01-01

    in abundance or biomass could be accounted for by the Law of Large Numbers, providing no evidence that specific ecological processes or co-adaptations are necessary to produce this effect. This implies that successful conservation policies to maintain the resilience of a marine fish community could be based......Functional redundancy of species sharing a feeding strategy and/or maximum size has been hypothesized to contribute to increased resilience of marine fish communities (the “portfolio effect”). A consistent time-series of survey data of fish in the North Sea was used to examine if trophic functional...... groups or maximum length of species (Lmax) groups with larger numbers of species had lower coefficients of variation in abundance and biomass over time than did groupings with fewer species. Results supported this hypothesis. However, the stabilizing effect of numbers of species in a group on variation...

  6. Optimal Strong-Stability-Preserving Runge–Kutta Time Discretizations for Discontinuous Galerkin Methods

    KAUST Repository

    Kubatko, Ethan J.; Yeager, Benjamin A.; Ketcheson, David I.

    2013-01-01

    Discontinuous Galerkin (DG) spatial discretizations are often used in a method-of-lines approach with explicit strong-stability-preserving (SSP) Runge–Kutta (RK) time steppers for the numerical solution of hyperbolic conservation laws. The time steps that are employed in this type of approach must satisfy Courant–Friedrichs–Lewy stability constraints that are dependent on both the region of absolute stability and the SSP coefficient of the RK method. While existing SSPRK methods have been optimized with respect to the latter, it is in fact the former that gives rise to stricter constraints on the time step in the case of RKDG stability. Therefore, in this work, we present the development of new “DG-optimized” SSPRK methods with stability regions that have been specifically designed to maximize the stable time step size for RKDG methods of a given order in one space dimension. These new methods represent the best available RKDG methods in terms of computational efficiency, with significant improvements over methods using existing SSPRK time steppers that have been optimized with respect to SSP coefficients. Second-, third-, and fourth-order methods with up to eight stages are presented, and their stability properties are verified through application to numerical test cases.

  7. Optimal Strong-Stability-Preserving Runge–Kutta Time Discretizations for Discontinuous Galerkin Methods

    KAUST Repository

    Kubatko, Ethan J.

    2013-10-29

    Discontinuous Galerkin (DG) spatial discretizations are often used in a method-of-lines approach with explicit strong-stability-preserving (SSP) Runge–Kutta (RK) time steppers for the numerical solution of hyperbolic conservation laws. The time steps that are employed in this type of approach must satisfy Courant–Friedrichs–Lewy stability constraints that are dependent on both the region of absolute stability and the SSP coefficient of the RK method. While existing SSPRK methods have been optimized with respect to the latter, it is in fact the former that gives rise to stricter constraints on the time step in the case of RKDG stability. Therefore, in this work, we present the development of new “DG-optimized” SSPRK methods with stability regions that have been specifically designed to maximize the stable time step size for RKDG methods of a given order in one space dimension. These new methods represent the best available RKDG methods in terms of computational efficiency, with significant improvements over methods using existing SSPRK time steppers that have been optimized with respect to SSP coefficients. Second-, third-, and fourth-order methods with up to eight stages are presented, and their stability properties are verified through application to numerical test cases.

  8. Self-Stabilization of Wait-Free Shared Memory Objects

    NARCIS (Netherlands)

    Hoepman, J.H.; Papatriantafilou, Marina; Tsigas, Philippas

    2002-01-01

    This paper proposes a general definition of self-stabilizing wait-free shared memory objects. The definition ensures that, even in the face of processor failures, every execution after a transient memory failure is linearizable except for an a priori bounded number of actions. Shared registers have

  9. Power System Stabilizer Design Based on a Particle Swarm Optimization Multiobjective Function Implemented Under Graphical Interface

    Directory of Open Access Journals (Sweden)

    Ghouraf Djamel Eddine

    2016-05-01

    Full Text Available Power system stability considered a necessary condition for normal functioning of an electrical network. The role of regulation and control systems is to ensure that stability by determining the essential elements that influence it. This paper proposes a Particle Swarm Optimization (PSO based multiobjective function to tuning optimal parameters of Power System Stabilizer (PSS; this later is used as auxiliary to generator excitation system in order to damp electro mechanicals oscillations of the rotor and consequently improve Power system stability. The computer simulation results obtained by developed graphical user interface (GUI have proved the efficiency of PSS optimized by a Particle Swarm Optimization, in comparison with a conventional PSS, showing stable   system   responses   almost   insensitive   to   large parameter variations.Our present study was performed using a GUI realized under MATLAB in our work.

  10. Marine protected areas increase temporal stability of community structure, but not density or diversity, of tropical seagrass fish communities.

    Directory of Open Access Journals (Sweden)

    Elisa Alonso Aller

    Full Text Available Marine protected areas (MPAs have been shown to increase long-term temporal stability of fish communities and enhance ecosystem resilience to anthropogenic disturbance. Yet, the potential ability of MPAs to buffer effects of environmental variability at shorter time scales remains widely unknown. In the tropics, the yearly monsoon cycle is a major natural force affecting marine organisms in tropical regions, and its timing and severity are predicted to change over the coming century, with potentially severe effects on marine organisms, ecosystems and ecosystem services. Here, we assessed the ability of MPAs to buffer effects of monsoon seasonality on seagrass-associated fish communities, using a field survey in two MPAs (no-take zones and two unprotected (open-access sites around Zanzibar (Tanzania. We assessed the temporal stability of fish density and community structure within and outside MPAs during three monsoon seasons in 2014-2015, and investigated several possible mechanisms that could regulate temporal stability. Our results show that MPAs did not affect fish density and diversity, but that juvenile fish densities were temporally more stable within MPAs. Second, fish community structure was more stable within MPAs for juvenile and adult fish, but not for subadult fish or the total fish community. Third, the observed effects may be due to a combination of direct and indirect (seagrass-mediated effects of seasonality and, potentially, fluctuating fishing pressure outside MPAs. In summary, these MPAs may not have the ability to enhance fish density and diversity and to buffer effects of monsoon seasonality on the whole fish community. However, they may increase the temporal stability of certain groups, such as juvenile fish. Consequently, our results question whether MPAs play a general role in the maintenance of biodiversity and ecosystem functioning under changing environmental conditions in tropical seagrass fish communities.

  11. Self-esteem and optimism in men and women infected with HIV.

    Science.gov (United States)

    Anderson, E H

    2000-01-01

    Self-esteem and optimism have been associated with appraisal and outcomes in a variety of situations. The degree to which the contribution of self-esteem and optimism to outcomes over time is accounted for by the differences in threat (primary) or resource (secondary) appraisal has not been established in persons with human immunodeficiency virus (HIV). To examine the longitudinal relationship of personality (self-esteem and optimism) on primary and secondary appraisal and outcomes of well-being, mood, CD4+ T-lymphocyte count, and selected activities. Men (n = 56) and women (n = 42) infected with HIV completed eight self-report measures twice over 18 months. Hierarchical Multiple Regressions were used to examine the relationship of personality variables on appraisals and outcomes. The mediating effects of primary and secondary appraisals were explored. Self-esteem uniquely accounted for 6% of the variance in primary appraisal and 5% in secondary appraisal. Optimism accounted for 8% of the unique variance in secondary appraisal. Primary and secondary appraisal mediated differently between personality and outcome variables. A strong predictor of well-being, mood disturbance, and activity disruption at Time 2 was participants' initial level of these variables. Socioeconomic status was a strong predictor of mood. Self-esteem and optimism are important but different resources for adapting to HIV disease. Strategies for reducing threats and increasing resources associated with HIV may improve an individual's mood and sense of well-being.

  12. The contribution of particle swarm optimization to three-dimensional slope stability analysis.

    Science.gov (United States)

    Kalatehjari, Roohollah; Rashid, Ahmad Safuan A; Ali, Nazri; Hajihassani, Mohsen

    2014-01-01

    Over the last few years, particle swarm optimization (PSO) has been extensively applied in various geotechnical engineering including slope stability analysis. However, this contribution was limited to two-dimensional (2D) slope stability analysis. This paper applied PSO in three-dimensional (3D) slope stability problem to determine the critical slip surface (CSS) of soil slopes. A detailed description of adopted PSO was presented to provide a good basis for more contribution of this technique to the field of 3D slope stability problems. A general rotating ellipsoid shape was introduced as the specific particle for 3D slope stability analysis. A detailed sensitivity analysis was designed and performed to find the optimum values of parameters of PSO. Example problems were used to evaluate the applicability of PSO in determining the CSS of 3D slopes. The first example presented a comparison between the results of PSO and PLAXI-3D finite element software and the second example compared the ability of PSO to determine the CSS of 3D slopes with other optimization methods from the literature. The results demonstrated the efficiency and effectiveness of PSO in determining the CSS of 3D soil slopes.

  13. The Contribution of Particle Swarm Optimization to Three-Dimensional Slope Stability Analysis

    Science.gov (United States)

    A Rashid, Ahmad Safuan; Ali, Nazri

    2014-01-01

    Over the last few years, particle swarm optimization (PSO) has been extensively applied in various geotechnical engineering including slope stability analysis. However, this contribution was limited to two-dimensional (2D) slope stability analysis. This paper applied PSO in three-dimensional (3D) slope stability problem to determine the critical slip surface (CSS) of soil slopes. A detailed description of adopted PSO was presented to provide a good basis for more contribution of this technique to the field of 3D slope stability problems. A general rotating ellipsoid shape was introduced as the specific particle for 3D slope stability analysis. A detailed sensitivity analysis was designed and performed to find the optimum values of parameters of PSO. Example problems were used to evaluate the applicability of PSO in determining the CSS of 3D slopes. The first example presented a comparison between the results of PSO and PLAXI-3D finite element software and the second example compared the ability of PSO to determine the CSS of 3D slopes with other optimization methods from the literature. The results demonstrated the efficiency and effectiveness of PSO in determining the CSS of 3D soil slopes. PMID:24991652

  14. The Contribution of Particle Swarm Optimization to Three-Dimensional Slope Stability Analysis

    Directory of Open Access Journals (Sweden)

    Roohollah Kalatehjari

    2014-01-01

    Full Text Available Over the last few years, particle swarm optimization (PSO has been extensively applied in various geotechnical engineering including slope stability analysis. However, this contribution was limited to two-dimensional (2D slope stability analysis. This paper applied PSO in three-dimensional (3D slope stability problem to determine the critical slip surface (CSS of soil slopes. A detailed description of adopted PSO was presented to provide a good basis for more contribution of this technique to the field of 3D slope stability problems. A general rotating ellipsoid shape was introduced as the specific particle for 3D slope stability analysis. A detailed sensitivity analysis was designed and performed to find the optimum values of parameters of PSO. Example problems were used to evaluate the applicability of PSO in determining the CSS of 3D slopes. The first example presented a comparison between the results of PSO and PLAXI-3D finite element software and the second example compared the ability of PSO to determine the CSS of 3D slopes with other optimization methods from the literature. The results demonstrated the efficiency and effectiveness of PSO in determining the CSS of 3D soil slopes.

  15. Self-Perceived Stability and Change in Children's Competence

    Science.gov (United States)

    Vandenplas-Holper, Christiane; Roskam, Isabelle; Fontaine, Anne-Marie

    2010-01-01

    Using Harter's ("Child Dev" 53(1):87-97, 1982) perceived competence scale, this study integrates several paradigms related to the issues of self-perceived competence, stability or change and attributional theory. It examines how 268 Belgian and Portuguese fifth graders consider their scholastic, social and physical competence at present…

  16. Self-consistent adjoint analysis for topology optimization of electromagnetic waves

    Science.gov (United States)

    Deng, Yongbo; Korvink, Jan G.

    2018-05-01

    In topology optimization of electromagnetic waves, the Gâteaux differentiability of the conjugate operator to the complex field variable results in the complexity of the adjoint sensitivity, which evolves the original real-valued design variable to be complex during the iterative solution procedure. Therefore, the self-inconsistency of the adjoint sensitivity is presented. To enforce the self-consistency, the real part operator has been used to extract the real part of the sensitivity to keep the real-value property of the design variable. However, this enforced self-consistency can cause the problem that the derived structural topology has unreasonable dependence on the phase of the incident wave. To solve this problem, this article focuses on the self-consistent adjoint analysis of the topology optimization problems for electromagnetic waves. This self-consistent adjoint analysis is implemented by splitting the complex variables of the wave equations into the corresponding real parts and imaginary parts, sequentially substituting the split complex variables into the wave equations with deriving the coupled equations equivalent to the original wave equations, where the infinite free space is truncated by the perfectly matched layers. Then, the topology optimization problems of electromagnetic waves are transformed into the forms defined on real functional spaces instead of complex functional spaces; the adjoint analysis of the topology optimization problems is implemented on real functional spaces with removing the variational of the conjugate operator; the self-consistent adjoint sensitivity is derived, and the phase-dependence problem is avoided for the derived structural topology. Several numerical examples are implemented to demonstrate the robustness of the derived self-consistent adjoint analysis.

  17. Self-organizing dynamic stability of far-from-equilibrium biological systems

    Science.gov (United States)

    Ivanitskii, G. R.

    2017-10-01

    One indication of the stability of a living system is the variation of the system’s characteristic time scales. Underlying the stability mechanism are the structural hierarchy and self-organization of systems, factors that give rise to a positive (accelerating) feedback and a negative (braking) feedback. Information processing in the brain cortex plays a special role in highly organized living organisms.

  18. Predictors of Early Community Involvement: Advancing the Self and Caring for Others.

    Science.gov (United States)

    Lawford, Heather L; Ramey, Heather L

    2017-03-01

    Recent research on community involvement points to the importance of both agentic (advancing the self) and communal motives (serving others) as key predictors, though few studies have examined both simultaneously. At the same time, research has identified generativity, defined as concern for future generations as a legacy of the self, as particularly relevant for community involvement. Moreover, generativity involves both agentic and communal motives, meaning that advancing personal goals and caring for others are integrated in this construct. Therefore, the purpose of this study was to examine how individual differences in attributes pertaining to self and to others-specifically, self-esteem, initiative, and empathy-related to both generativity and community involvement. A sample of adolescents (N = 160; 64% female, M age  = 17) and a sample of young adults (N = 237; 84% female, M age  = 20) completed a survey including measures of community involvement and generativity. Generative concern fully mediated the associations between individual differences (self-esteem, initiative, and empathy) and community involvement, suggesting that the early generativity has a role in fostering capacities and contribution in youth. These developmental indicators pertaining to self and others link to actions that benefit the community through a desire to benefit future generations. © Society for Community Research and Action 2017.

  19. Primary stability and self-tapping blades: biomechanical assessment of dental implants in medium-density bone.

    Science.gov (United States)

    Kim, Yung-Soo; Lim, Young-Jun

    2011-10-01

    The aim of this biomechanical study was to assess the influence of self-tapping blades in terms of primary implant stability between implants with self-tapping blades and implants without self-tapping blades using five different analytic methods, especially in medium-density bone. Two different types of dental implants (4 × 10 mm) were tested: self-tapping and non-self-tapping. The fixture design including thread profiles was exactly the same between the two groups; the only difference was the presence of cutting blades on one half of the apical portion of the implant body. Solid rigid polyurethane blocks with corresponding densities were selected to simulate medium-density bone. Five mechanical assessments (insertion torque, resonance frequency analysis [RFA], reverse torque, pull-out and push in test) were performed for primary stability. Implants without self-tapping blades showed significantly higher values (P0.05). The outcomes of the present study indicate that the implant body design without self-tapping blades has a good primary stability compared with that with self-tapping blades in medium-density bone. Considering the RFA, a distinct layer of cortical bone on marginal bone will yield implant stability quotient values similar to those in medium-bone density when implants have the same diameter. © 2011 John Wiley & Sons A/S.

  20. Optimal exploitation of spatially distributed trophic resources and population stability

    Science.gov (United States)

    Basset, A.; Fedele, M.; DeAngelis, D.L.

    2002-01-01

    The relationships between optimal foraging of individuals and population stability are addressed by testing, with a spatially explicit model, the effect of patch departure behaviour on individual energetics and population stability. A factorial experimental design was used to analyse the relevance of the behavioural factor in relation to three factors that are known to affect individual energetics; i.e. resource growth rate (RGR), assimilation efficiency (AE), and body size of individuals. The factorial combination of these factors produced 432 cases, and 1000 replicate simulations were run for each case. Net energy intake rates of the modelled consumers increased with increasing RGR, consumer AE, and consumer body size, as expected. Moreover, through their patch departure behaviour, by selecting the resource level at which they departed from the patch, individuals managed to substantially increase their net energy intake rates. Population stability was also affected by the behavioural factors and by the other factors, but with highly non-linear responses. Whenever resources were limiting for the consumers because of low RGR, large individual body size or low AE, population density at the equilibrium was directly related to the patch departure behaviour; on the other hand, optimal patch departure behaviour, which maximised the net energy intake at the individual level, had a negative influence on population stability whenever resource availability was high for the consumers. The consumer growth rate (r) and numerical dynamics, as well as the spatial and temporal fluctuations of resource density, which were the proximate causes of population stability or instability, were affected by the behavioural factor as strongly or even more strongly than by the others factors considered here. Therefore, patch departure behaviour can act as a feedback control of individual energetics, allowing consumers to optimise a potential trade-off between short-term individual fitness

  1. Preparation and thermal stability of nickel nanowires via self ...

    Indian Academy of Sciences (India)

    Administrator

    Nickel nanowires; magnetic field; self-assembly; thermal stability. 1. Introduction ... vapour-phase techniques mainly include methods such as chemical ... 2.1 Materials and methods .... sum up, the colour change of NiO may be caused by the.

  2. Requirements for Self-Stabilization of Distributed Advanced Battle Managers

    National Research Council Canada - National Science Library

    Auguston, Mikhail; Cook, Thomas S; Michael, James B; Shing, Man-Tak; Tummala, Harsha; Wijesekera, Duminda; Xie, Geoffrey G

    2006-01-01

    .... We then describe a sub-area of self-stabilization known as the leader election problem, pointing out the issues tied to the re-establishment of an ABM command and control structure in the event of system faults...

  3. Robust Video Stabilization Using Particle Keypoint Update and l1-Optimized Camera Path

    Directory of Open Access Journals (Sweden)

    Semi Jeon

    2017-02-01

    Full Text Available Acquisition of stabilized video is an important issue for various type of digital cameras. This paper presents an adaptive camera path estimation method using robust feature detection to remove shaky artifacts in a video. The proposed algorithm consists of three steps: (i robust feature detection using particle keypoints between adjacent frames; (ii camera path estimation and smoothing; and (iii rendering to reconstruct a stabilized video. As a result, the proposed algorithm can estimate the optimal homography by redefining important feature points in the flat region using particle keypoints. In addition, stabilized frames with less holes can be generated from the optimal, adaptive camera path that minimizes a temporal total variation (TV. The proposed video stabilization method is suitable for enhancing the visual quality for various portable cameras and can be applied to robot vision, driving assistant systems, and visual surveillance systems.

  4. Optimization Analysis Model of Self-Anchored Suspension Bridge

    Directory of Open Access Journals (Sweden)

    Pengzhen Lu

    2014-01-01

    Full Text Available The hangers of self-anchored suspension bridge need to be tensioned suitably during construction. In view of this point, a simplified optimization calculation method of cable force for self-anchored suspension bridge has been developed based on optimization theories, such as minimum bending energy method, and internal force balanced method, influence matrix method. Meanwhile, combined with the weak coherence of main cable and the adjacently interaction of hanger forces, a simplified analysis method is developed using MATLAB, which is then compared with the optimization method that consider the main cable's geometric nonlinearity with software ANSYS in an actual example bridge calculation. This contrast proves the weak coherence of main cable displacement and the limitation of the adjacent cable force influence. Furthermore, a tension program that is of great reference value has been developed; some important conclusions, advices, and attention points have been summarized.

  5. Model Checking A Self-Stabilizing Synchronization Protocol for Arbitrary Digraphs

    Science.gov (United States)

    Malekpour, Mahyar R.

    2012-01-01

    This report presents the mechanical verification of a self-stabilizing distributed clock synchronization protocol for arbitrary digraphs in the absence of faults. This protocol does not rely on assumptions about the initial state of the system, other than the presence of at least one node, and no central clock or a centrally generated signal, pulse, or message is used. The system under study is an arbitrary, non-partitioned digraph ranging from fully connected to 1-connected networks of nodes while allowing for differences in the network elements. Nodes are anonymous, i.e., they do not have unique identities. There is no theoretical limit on the maximum number of participating nodes. The only constraint on the behavior of the node is that the interactions with other nodes are restricted to defined links and interfaces. This protocol deterministically converges within a time bound that is a linear function of the self-stabilization period. A bounded model of the protocol is verified using the Symbolic Model Verifier (SMV) for a subset of digraphs. Modeling challenges of the protocol and the system are addressed. The model checking effort is focused on verifying correctness of the bounded model of the protocol as well as confirmation of claims of determinism and linear convergence with respect to the self-stabilization period.

  6. Requirements for Self-Stabilization of Distributed Advanced Battle Managers

    National Research Council Canada - National Science Library

    Auguston, Mikhail; Cook, Thomas S; Michael, James B; Shing, Man-Tak; Tummala, Harsha; Wijesekera, Duminda; Xie, Geoffrey G

    2006-01-01

    In this report, we formalize the self-stabilization problem as it pertains to the C2BMC, in addition to highlighting some of key features of the C2BMC that distinguish it from general-purpose distributed systems...

  7. Unrealistic Optimism: Self-Enhancement or Person Positivity?

    Science.gov (United States)

    Regan, Pamela C.; And Others

    1995-01-01

    Two studies examined whether people are unrealistically optimistic only for their own futures or for the future of any individual. Results suggested that unrealistic optimism is a form of self-enhancement rather than person positivity bias. (JBJ)

  8. Liquid Self-Balancing Device Effects on Flexible Rotor Stability

    Directory of Open Access Journals (Sweden)

    Leonardo Urbiola-Soto

    2013-01-01

    Full Text Available Nearly a century ago, the liquid self-balancing device was first introduced by M. LeBlanc for passive balancing of turbine rotors. Although of common use in many types or rotating machines nowadays, little information is available on the unbalance response and stability characteristics of this device. Experimental fluid flow visualization evidences that radial and traverse circulatory waves arise due to the interaction of the fluid backward rotation and the baffle boards within the self-balancer annular cavity. The otherwise destabilizing force induced by trapped fluids in hollow rotors, becomes a stabilizing mechanism when the cavity is equipped with adequate baffle boards. Further experiments using Particle Image Velocimetry (PIV enable to assess the active fluid mass fraction to be one-third of the total fluid mass. An analytical model is introduced to study the effects of the active fluid mass fraction on a flexible rotor supported by flexible supports excited by bwo different destabilizing mechanisms; rotor internal friction damping and aerodynamic cross-coupling. It is found that the fluid radial and traverse forces contribute to the balancing action and to improve the rotor stability, respectively.

  9. Self-focusing, self modulation and stability properties of laser beam propagating in plasma: A variational approach

    International Nuclear Information System (INIS)

    Kaur, Ravinder; Gill, Tarsem Singh; Mahajan, Ranju

    2010-01-01

    Laboratory as well as Particle in cell (PIC) simulation experiments reveal the strong flow of energetic electrons co-moving with laser beam in laser plasma interaction. Equation governing the evolution of complex envelope in slowly varying envelope approximation is nonlinear parabolic equation. A Lagrangian for the problem is set up and assuming a trial Gaussian profile, we solve the reduced Lagrangian problem for beam width and curvature. Besides self-focusing and self-modulation of laser beam, we observe that stability properties of such plasma system are studied about equilibrium values using this variational approach. We obtained an eigen value equation, which is cubic in nature and investigated the criterion for stability using Hurwitz conditions for laser beam plasma system.

  10. Design optimization and analysis of selected thermal devices using self-adaptive Jaya algorithm

    International Nuclear Information System (INIS)

    Rao, R.V.; More, K.C.

    2017-01-01

    Highlights: • Self-adaptive Jaya algorithm is proposed for optimal design of thermal devices. • Optimization of heat pipe, cooling tower, heat sink and thermo-acoustic prime mover is presented. • Results of the proposed algorithm are better than the other optimization techniques. • The proposed algorithm may be conveniently used for the optimization of other devices. - Abstract: The present study explores the use of an improved Jaya algorithm called self-adaptive Jaya algorithm for optimal design of selected thermal devices viz; heat pipe, cooling tower, honeycomb heat sink and thermo-acoustic prime mover. Four different optimization case studies of the selected thermal devices are presented. The researchers had attempted the same design problems in the past using niched pareto genetic algorithm (NPGA), response surface method (RSM), leap-frog optimization program with constraints (LFOPC) algorithm, teaching-learning based optimization (TLBO) algorithm, grenade explosion method (GEM) and multi-objective genetic algorithm (MOGA). The results achieved by using self-adaptive Jaya algorithm are compared with those achieved by using the NPGA, RSM, LFOPC, TLBO, GEM and MOGA algorithms. The self-adaptive Jaya algorithm is proved superior as compared to the other optimization methods in terms of the results, computational effort and function evalutions.

  11. Optimal Subinterval Selection Approach for Power System Transient Stability Simulation

    Directory of Open Access Journals (Sweden)

    Soobae Kim

    2015-10-01

    Full Text Available Power system transient stability analysis requires an appropriate integration time step to avoid numerical instability as well as to reduce computational demands. For fast system dynamics, which vary more rapidly than what the time step covers, a fraction of the time step, called a subinterval, is used. However, the optimal value of this subinterval is not easily determined because the analysis of the system dynamics might be required. This selection is usually made from engineering experiences, and perhaps trial and error. This paper proposes an optimal subinterval selection approach for power system transient stability analysis, which is based on modal analysis using a single machine infinite bus (SMIB system. Fast system dynamics are identified with the modal analysis and the SMIB system is used focusing on fast local modes. An appropriate subinterval time step from the proposed approach can reduce computational burden and achieve accurate simulation responses as well. The performance of the proposed method is demonstrated with the GSO 37-bus system.

  12. Stability of self-gravitating homogeneous spheroid with azimuthal magnetic field. I

    International Nuclear Information System (INIS)

    Antonov, V.A.; Zheleznyak, O.A.

    1988-01-01

    The influence of a frozen magnetic field on the stability of a self-gravitating homogeneous spheroid with respect to a deformation that transforms it into a triaxial ellipsoid is investigated. It is shown that an azimuthal magnetic field is a stabilizing factor, allowing the spheroid to be stable at e > e/sub cr/ = 0.95285

  13. Stabilizing photoassociated Cs2 molecules by optimal control

    International Nuclear Information System (INIS)

    Zhang Wei; Xie Ting; Huang Yin; Wang Gao-Ren; Cong Shu-Lin

    2013-01-01

    We demonstrate theoretically that photoassociated molecules can be stabilized to deeply bound states. This process is achieved by transferring the population from the outer well to the inner well using the optimal control theory, the Cs 2 molecule is taken as an example. Numerical calculations show that weakly bound molecules formed in the outer well by a pump pulse can be compressed to the inner well via a vibrational level of the ground electronic state as an intermediary by an additionally optimized laser pulse. The positively chirped pulse can enhance the population of the target state. With a transform-limited dump pulse, nearly all the photoassociated molecules in the inner well of the excited electronic state can be transferred to the deeply vibrational level of the ground electronic state. (atomic and molecular physics)

  14. Stabilizing photoassociated Cs2 molecules by optimal control

    Science.gov (United States)

    Zhang, Wei; Xie, Ting; Huang, Yin; Wang, Gao-Ren; Cong, Shu-Lin

    2013-01-01

    We demonstrate theoretically that photoassociated molecules can be stabilized to deeply bound states. This process is achieved by transferring the population from the outer well to the inner well using the optimal control theory, the Cs2 molecule is taken as an example. Numerical calculations show that weakly bound molecules formed in the outer well by a pump pulse can be compressed to the inner well via a vibrational level of the ground electronic state as an intermediary by an additionally optimized laser pulse. The positively chirped pulse can enhance the population of the target state. With a transform-limited dump pulse, nearly all the photoassociated molecules in the inner well of the excited electronic state can be transferred to the deeply vibrational level of the ground electronic state.

  15. Enhancing Economic Stability Utilizing the High Technologies in Community Colleges: A Case Study.

    Science.gov (United States)

    Mehnert, Barbara H.; Kurki, Allan W.

    Strategies to enhance the economic stability of community colleges through high technology approaches are discussed in this paper. First, general economic problems facing higher education are identified, and the ways in which they influence community colleges are described. Next, 10 strategies to aid in the economic recovery of community colleges…

  16. A chaos wolf optimization algorithm with self-adaptive variable step-size

    Science.gov (United States)

    Zhu, Yong; Jiang, Wanlu; Kong, Xiangdong; Quan, Lingxiao; Zhang, Yongshun

    2017-10-01

    To explore the problem of parameter optimization for complex nonlinear function, a chaos wolf optimization algorithm (CWOA) with self-adaptive variable step-size was proposed. The algorithm was based on the swarm intelligence of wolf pack, which fully simulated the predation behavior and prey distribution way of wolves. It possessed three intelligent behaviors such as migration, summons and siege. And the competition rule as "winner-take-all" and the update mechanism as "survival of the fittest" were also the characteristics of the algorithm. Moreover, it combined the strategies of self-adaptive variable step-size search and chaos optimization. The CWOA was utilized in parameter optimization of twelve typical and complex nonlinear functions. And the obtained results were compared with many existing algorithms, including the classical genetic algorithm, the particle swarm optimization algorithm and the leader wolf pack search algorithm. The investigation results indicate that CWOA possess preferable optimization ability. There are advantages in optimization accuracy and convergence rate. Furthermore, it demonstrates high robustness and global searching ability.

  17. Unfinished dreams: community healing and the reality of aboriginal self-government

    National Research Council Canada - National Science Library

    Warry, Wayne

    1998-01-01

    ... of community development and cultural revitalization that are essential precursors to self-government. Warry's notion of 'community healing' involves efforts to rebuild the human foundations for self-governing Aboriginal societies. The book analyses key areas such as health care and the judicial and political systems where Aboriginal peoples ...

  18. Wellness and illness self-management skills in community corrections.

    Science.gov (United States)

    Kelly, Patricia J; Ramaswamy, Megha; Chen, Hsiang-Feng; Denny, Donald

    2015-02-01

    Community corrections provide a readjustment venue for re-entry between incarceration and home for inmates in the US corrections system. Our goal was to determine how self-management skills, an important predictor of re-entry success, varied by demographic and risk factors. In this cross-sectional study, we analyzed responses of 675 clients from 57 community corrections programs run by the regional division of the Federal Bureau of Prisons. A self-administered survey collected data on self-management skills, demographics, and risk factors; significant associations were applied in four regression models: the overall self-management score and three self-management subscales: coping skills, goals, and drug use. Over one-quarter (27.2%/146) of participants had a mental health history. White race, no mental health history and high school education were associated with better overall self-management scores; mental health history and drug use in the past year were associated with lower coping scores; female gender and high school education were associated with better self-management goals; female gender was associated with better self-management drug use scores. Self-management programs may need to be individualized for different groups of clients. Lower scores for those with less education suggest an area for targeted, nurse-led interventions.

  19. Stability Analysis and Optimal Control Strategy for Prevention of Pine Wilt Disease

    Directory of Open Access Journals (Sweden)

    Kwang Sung Lee

    2014-01-01

    Full Text Available We propose a mathematical model of pine wilt disease (PWD which is caused by pine sawyer beetles carrying the pinewood nematode (PWN. We calculate the basic reproduction number R0 and investigate the stability of a disease-free and endemic equilibrium in a given mathematical model. We show that the stability of the equilibrium in the proposed model can be controlled through the basic reproduction number R0. We then discuss effective optimal control strategies for the proposed PWD mathematical model. We demonstrate the existence of a control problem, and then we apply both analytical and numerical techniques to demonstrate effective control methods to prevent the transmission of the PWD. In order to do this, we apply two control strategies: tree-injection of nematicide and the eradication of adult beetles through aerial pesticide spraying. Optimal prevention strategies can be determined by solving the corresponding optimality system. Numerical simulations of the optimal control problem using a set of reasonable parameter values suggest that reducing the number of pine sawyer beetles is more effective than the tree-injection strategy for controlling the spread of PWD.

  20. Optimal tariff design under consumer self-selection

    Energy Technology Data Exchange (ETDEWEB)

    Raesaenen, M.; Ruusunen, J.; Haemaelaeinen, R.

    1995-12-31

    This report considers the design of electricity tariffs which guides an individual consumer to select the tariff designed for his consumption pattern. In the model the utility maximizes the weighted sum of individual consumers` benefits of electricity consumption subject to the utility`s revenue requirement constraints. The consumers` free choice of tariffs is ensured with the so-called self-selection constraints. The relationship between the consumers` optimal choice of tariffs and the weights in the aggregated consumers` benefit function is analyzed. If such weights exist, they will guarantee both the consumers` optimal choice of tariffs and the efficient consumption patterns. Also the welfare effects are analyzed by using demand parameters estimated from a Finnish dynamic pricing experiment. The results indicate that it is possible to design an efficient tariff menu with the welfare losses caused by the self-selection constraints being small compared with the costs created when some consumers choose tariffs other than assigned for them. (author)

  1. Discharge optimization and the control of edge stability

    International Nuclear Information System (INIS)

    Nave, M.F.F.; Lomas, P.J.; Huysmans, G.T.A.

    1999-01-01

    Discharge optimization for improving MHD stability of both core and edge was essential for the achievement of record fusion power discharges, in the ELM-free hot ion H mode regime, in the recent JET DT operation. The techniques used to increase edge stability are described. In particular the successful technique of current rampdown used to suppress the outer mode is reported. The increased stability of the outer mode by decreasing the edge current density confirms its identification as an n = 1 external kink. Decreasing the plasma current, however, decreases the ELM-free period, which is consistent with stability calculations that show an earlier onset of the ballooning limit. In order to increase external kink stability without causing a deterioration in the ELM-free period, a compromise was achieved by using plasma current rampdown, while working at the highest plasma current values possible. Results from a plasma current scan show that at the time of occurrence of the first giant ELM, the plasma stored energy, as well as the pressure measured at the top of the edge pedestal increase linearly with plasma current, for a given plasma configuration and power. This is consistent with models of the edge transport barrier, where the transport barrier width is proportional to the ion (or fast ion) poloidal Larmor radius. The MHD observations in DT and deuterium only discharges were found to be similar. Thus the experience gained on the control of MHD modes in deuterium plasmas could be fully exploited in the DT campaign. (author)

  2. Optimizing real power loss and voltage stability limit of a large transmission network using firefly algorithm

    Directory of Open Access Journals (Sweden)

    P. Balachennaiah

    2016-06-01

    Full Text Available This paper proposes a Firefly algorithm based technique to optimize the control variables for simultaneous optimization of real power loss and voltage stability limit of the transmission system. Mathematically, this issue can be formulated as nonlinear equality and inequality constrained optimization problem with an objective function integrating both real power loss and voltage stability limit. Transformers taps, unified power flow controller and its parameters have been included as control variables in the problem formulation. The effectiveness of the proposed algorithm has been tested on New England 39-bus system. Simulation results obtained with the proposed algorithm are compared with the real coded genetic algorithm for single objective of real power loss minimization and multi-objective of real power loss minimization and voltage stability limit maximization. Also, a classical optimization method known as interior point successive linear programming technique is considered here to compare the results of firefly algorithm for single objective of real power loss minimization. Simulation results confirm the potentiality of the proposed algorithm in solving optimization problems.

  3. Weighted Evolving Networks with Self-organized Communities

    International Nuclear Information System (INIS)

    Xie Zhou; Wang Xiaofan; Li Xiang

    2008-01-01

    In order to describe the self-organization of communities in the evolution of weighted networks, we propose a new evolving model for weighted community-structured networks with the preferential mechanisms functioned in different levels according to community sizes and node strengths, respectively. Theoretical analyses and numerical simulations show that our model captures power-law distributions of community sizes, node strengths, and link weights, with tunable exponents of ν ≥ 1, γ > 2, and α > 2, respectively, sharing large clustering coefficients and scaling clustering spectra, and covering the range from disassortative networks to assortative networks. Finally, we apply our new model to the scientific co-authorship networks with both their weighted and unweighted datasets to verify its effectiveness

  4. Mean-variance portfolio analysis data for optimizing community-based photovoltaic investment

    Directory of Open Access Journals (Sweden)

    Mahmoud Shakouri

    2016-03-01

    Full Text Available The amount of electricity generated by Photovoltaic (PV systems is affected by factors such as shading, building orientation and roof slope. To increase electricity generation and reduce volatility in generation of PV systems, a portfolio of PV systems can be made which takes advantages of the potential synergy among neighboring buildings. This paper contains data supporting the research article entitled: PACPIM: new decision-support model of optimized portfolio analysis for community-based photovoltaic investment [1]. We present a set of data relating to physical properties of 24 houses in Oregon, USA, along with simulated hourly electricity data for the installed PV systems. The developed Matlab code to construct optimized portfolios is also provided in Supplementary materials. The application of these files can be generalized to variety of communities interested in investing on PV systems. Keywords: Community solar, Photovoltaic system, Portfolio theory, Energy optimization, Electricity volatility

  5. Small Signal Stability Improvement of Power Systems Using Optimal Load Responses in Competitive Electricity Markets

    DEFF Research Database (Denmark)

    Hu, Weihao; Su, Chi; Chen, Zhe

    2011-01-01

    Since the hourly spot market price is available one day ahead in Denmark, the price could be transferred to the consumers and they may shift some of their loads from high price periods to the low price periods in order to save their energy costs. The optimal load response to an electricity price...... price is proposed. A 17-bus power system with high wind power penetrations, which resembles the Eastern Danish power system, is chosen as the study case. Simulation results show that the optimal load response to electricity prices is an effective measure to improve the small signal stability of power...... for demand side management generates different load profiles and may provide an opportunity to improve the small signal stability of power systems with high wind power penetrations. In this paper, the idea of power system small signal stability improvement by using optimal load response to the electricity...

  6. Optimal Robust Self-Testing by Binary Nonlocal XOR Games

    OpenAIRE

    Miller, Carl A.; Shi, Yaoyun

    2013-01-01

    Self-testing a quantum apparatus means verifying the existence of a certain quantum state as well as the effect of the associated measuring devices based only on the statistics of the measurement outcomes. Robust (i.e., error-tolerant) self-testing quantum apparatuses are critical building blocks for quantum cryptographic protocols that rely on imperfect or untrusted devices. We devise a general scheme for proving optimal robust self-testing properties for tests based on nonlocal binary XOR g...

  7. A chaos wolf optimization algorithm with self-adaptive variable step-size

    Directory of Open Access Journals (Sweden)

    Yong Zhu

    2017-10-01

    Full Text Available To explore the problem of parameter optimization for complex nonlinear function, a chaos wolf optimization algorithm (CWOA with self-adaptive variable step-size was proposed. The algorithm was based on the swarm intelligence of wolf pack, which fully simulated the predation behavior and prey distribution way of wolves. It possessed three intelligent behaviors such as migration, summons and siege. And the competition rule as “winner-take-all” and the update mechanism as “survival of the fittest” were also the characteristics of the algorithm. Moreover, it combined the strategies of self-adaptive variable step-size search and chaos optimization. The CWOA was utilized in parameter optimization of twelve typical and complex nonlinear functions. And the obtained results were compared with many existing algorithms, including the classical genetic algorithm, the particle swarm optimization algorithm and the leader wolf pack search algorithm. The investigation results indicate that CWOA possess preferable optimization ability. There are advantages in optimization accuracy and convergence rate. Furthermore, it demonstrates high robustness and global searching ability.

  8. Stability Constrained Efficiency Optimization for Droop Controlled DC-DC Conversion System

    DEFF Research Database (Denmark)

    Meng, Lexuan; Dragicevic, Tomislav; Guerrero, Josep M.

    2013-01-01

    implementing tertiary regulation. Moreover, system dynamic is affected when shifting VRs. Therefore, the stability is considered in optimization by constraining the eigenvalues arising from dynamic state space model of the system. Genetic algorithm is used in searching for global efficiency optimum while....... As the efficiency of each converter changes with output power, virtual resistances (VRs) are set as decision variables for adjusting power sharing proportion among converters. It is noteworthy that apart from restoring the voltage deviation, secondary control plays an important role to stabilize dc bus voltage when...

  9. Optimism, community attachment and serostatus disclosure among HIV-positive men who have sex with men.

    Science.gov (United States)

    Murphy, Patrick J; Hevey, David; O'Dea, Siobhán; Ní Rathaille, Neans; Mulcahy, Fiona

    2015-01-01

    This study investigated the relationship between HIV health optimism (HHO) (the belief that health will remain good after HIV infection due to treatment efficacy), HIV-positive community attachment (HCA), gay community attachment (GCA) and serostatus disclosure to casual sex partners by HIV-positive men who have sex with men (MSM). Cross-sectional questionnaire data were gathered from 97 HIV-positive MSM attending an HIV treatment clinic in Dublin, Ireland. Based on self-reported disclosure to casual partners, participants were classified according to their pattern of disclosure (consistent, inconsistent or non-disclosers). Multinomial logistic regression was used to assess HHO, HCA and GCA as predictors of participants' pattern of disclosure. Classification as a non-discloser (compared to a consistent discloser) was associated with higher HHO, less HCA and greater GCA. Classification as an inconsistent discloser (compared to a consistent discloser) was associated with higher GCA. The study provided novel quantitative evidence for associations between the constructs of interest. The results suggest that (1) HHO is associated with reduced disclosure, suggesting optimism may preclude individuals reaping the benefits of serostatus disclosure and (2) HCA and GCA represent competing attachments with conflicting effects on disclosure behaviour. Limitations and areas for future research are discussed.

  10. An Optimal Commitment Model of Exchange Rate Stabilization

    OpenAIRE

    Kyung-Soo Kim

    2006-01-01

    Recently East Asian countries that have amassed large US dollar reserves face a growing threat of big losses from a sudden decline in the dollar. This threat evokes an issue of the optimal commitment of exchange rate stabilization once raised by Isard (1995) who interpreted the cost of breaking the parity as the capital gain awarded to speculators, in the event the domestic currency is devalued. The only difference in this paper is revaluation. This paper models the central bank��s optima...

  11. A new optimized self-firing mos-thyristor device

    Energy Technology Data Exchange (ETDEWEB)

    Breil, M.; Sanchez, J.L.; Austin, P.; Laur, J.P.

    1998-12-01

    In this paper, a new integrated self-firing and controlled turn-off MOS-thyristor structure is investigated. An analytical model describing the turn-off operation and parasitic latch-up has been developed, allowing to highlight and optimize the physical and geometrical parameters acting upon main electrical characteristics. The analytical model is validated by 2D simulations using PISCES. The technological fabrication process is optimized by 2D simulations using SUPREM IV. Electrical characterization results of fabricated test structures are presented. (authors) 6 refs.

  12. Optimization and stability of the contrast transfer function in aberration-corrected electron microscopy

    International Nuclear Information System (INIS)

    Tromp, R.M.; Schramm, S.M.

    2013-01-01

    The Contrast Transfer Function (CTF) describes the manner in which the electron microscope modifies the object exit wave function as a result of objective lens aberrations. For optimum resolution in C 3 -corrected microscopes it is well established that a small negative value of C 3 , offset by positive values of C 5 and defocus C 1 results in the most optimal instrument resolution, and optimization of the CTF has been the subject of several studies. Here we describe a simple design procedure for the CTF that results in a most even transfer of information below the resolution limit. We address not only the resolution of the instrument, but also the stability of the CTF in the presence of small disturbances in C 1 and C 3 . We show that resolution can be traded for stability in a rational and transparent fashion. These topics are discussed quantitatively for both weak-phase and strong-phase (or amplitude) objects. The results apply equally to instruments at high electron energy (TEM) and at very low electron energy (LEEM), as the basic optical properties of the imaging lenses are essentially identical. - Highlights: ► An optimized Contrast Transfer Function for aberration corrected electron microscopes is proposed. ► Based on the properties of the CTF near optimum settings, we address its stability. ► Over some range of parameters resolution can be traded for stability. ► These issues are addressed for weak-phase objects, as well as strong-phase and amplitude object. ► We compare our results with CTF settings previously proposed

  13. A Self-Stabilizing Hybrid-Fault Tolerant Synchronization Protocol

    Science.gov (United States)

    Malekpour, Mahyar R.

    2014-01-01

    In this report we present a strategy for solving the Byzantine general problem for self-stabilizing a fully connected network from an arbitrary state and in the presence of any number of faults with various severities including any number of arbitrary (Byzantine) faulty nodes. Our solution applies to realizable systems, while allowing for differences in the network elements, provided that the number of arbitrary faults is not more than a third of the network size. The only constraint on the behavior of a node is that the interactions with other nodes are restricted to defined links and interfaces. Our solution does not rely on assumptions about the initial state of the system and no central clock nor centrally generated signal, pulse, or message is used. Nodes are anonymous, i.e., they do not have unique identities. We also present a mechanical verification of a proposed protocol. A bounded model of the protocol is verified using the Symbolic Model Verifier (SMV). The model checking effort is focused on verifying correctness of the bounded model of the protocol as well as confirming claims of determinism and linear convergence with respect to the self-stabilization period. We believe that our proposed solution solves the general case of the clock synchronization problem.

  14. Stress, Self-Esteem, Hope, Optimism, and Well-Being in Urban, Ethnic Minority Adolescents

    Science.gov (United States)

    Vacek, Kimberly R.; Coyle, Laura D.; Vera, Elizabeth M.

    2010-01-01

    This study examined hope, optimism, self-esteem, social support, stress, and indices of subjective well-being (SWB) in 137 low-income, urban, ethnic minority adolescents. Hope, optimism, and self-esteem were significant predictors of SWB indices, but stress predicted only 1 SWB index: negative affect. No moderators of stress and negative affect…

  15. Specificity of the Best Possible Self intervention for increasing optimism: Comparison with a gratitude intervention

    OpenAIRE

    Peters, Madelon L; Meevissen, Yvo M. C; Hanssen, Marjolein M

    2013-01-01

    The present study compared the effects of a one week best possible self intervention and a one week gratitude intervention on life satisfaction and optimism. We hypothesized that both interventions would lead to similar increases in life satisfaction, but that only the best possible self intervention would increase optimism. The results partly confirmed the hypotheses: only the best possible self intervention led to increased optimism immediately after the intervention period, which further i...

  16. A heuristic approach to optimization of structural topology including self-weight

    Science.gov (United States)

    Tajs-Zielińska, Katarzyna; Bochenek, Bogdan

    2018-01-01

    Topology optimization of structures under a design-dependent self-weight load is investigated in this paper. The problem deserves attention because of its significant importance in the engineering practice, especially nowadays as topology optimization is more often applied when designing large engineering structures, for example, bridges or carrying systems of tall buildings. It is worth noting that well-known approaches of topology optimization which have been successfully applied to structures under fixed loads cannot be directly adapted to the case of design-dependent loads, so that topology generation can be a challenge also for numerical algorithms. The paper presents the application of a simple but efficient non-gradient method to topology optimization of elastic structures under self-weight loading. The algorithm is based on the Cellular Automata concept, the application of which can produce effective solutions with low computational cost.

  17. Prevalence, Incidence and stability of premenstrual dysphoric disorder in the community

    NARCIS (Netherlands)

    Wittchen, H.U.; Becker, E.S.; Lieb, R.; Krause, P.

    2002-01-01

    Background. Despite an abundance of clinical research on premenstrual and menstrual symptoms. few epidemiological data provide estimates of the prevalence, incidence, co-morbidity, stability and correlates of premenstrual dysphoric disorder (PMDD) in the community. Aims. To describe the prevalence,

  18. Collaboration Strategies in Nontraditional Community-Based Participatory Research Partnerships: Lessons From an Academic–Community Partnership With Autistic Self-Advocates

    Science.gov (United States)

    Nicolaidis, Christina; Raymaker, Dora; McDonald, Katherine; Dern, Sebastian; Ashkenazy, Elesia; Boisclair, Cody; Robertson, Scott; Baggs, Amanda

    2012-01-01

    Background Most community-based participatory research (CBPR) projects involve local communities defined by race, ethnicity, geography, or occupation. Autistic self-advocates, a geographically dispersed community defined by disability, experience issues in research similar to those expressed by more traditional minorities. Objectives We sought to build an academic–community partnership that uses CBPR to improve the lives of people on the autistic spectrum. Methods The Academic Autistic Spectrum Partnership in Research and Education (AASPIRE) includes representatives from academic, self-advocate, family, and professional communities. We are currently conducting several studies about the health care experiences and well-being of autistic adults. Lessons Learned We have learned a number of strategies that integrate technology and process to successfully equalize power and accommodate diverse communication and collaboration needs. Conclusions CBPR can be conducted successfully with autistic self-advocates. Our strategies may be useful to other CBPR partnerships, especially ones that cannot meet in person or that include people with diverse communication needs. PMID:21623016

  19. 5G heterogeneous networks self-organizing and optimization

    CERN Document Server

    Rong, Bo; Kadoch, Michel; Sun, Songlin; Li, Wenjing

    2016-01-01

    This SpringerBrief provides state-of-the-art technical reviews on self-organizing and optimization in 5G systems. It covers the latest research results from physical-layer channel modeling to software defined network (SDN) architecture. This book focuses on the cutting-edge wireless technologies such as heterogeneous networks (HetNets), self-organizing network (SON), smart low power node (LPN), 3D-MIMO, and more. It will help researchers from both the academic and industrial worlds to better understand the technical momentum of 5G key technologies.

  20. Trait diversity promotes stability of community dynamics

    DEFF Research Database (Denmark)

    Zhang, Lai; Thygesen, Uffe Høgsbro; Knudsen, Kim

    2013-01-01

    body size. The dynamic properties of the models are described by a stability analysis of equilibrium solutions and by the non-equilibrium dynamics. We find that the introduction of trait diversity expands the set of parameters for which the equilibrium is stable and, if the community is unstable, makes....... The analysis is performed by comparing the properties of two size spectrum models. The first model considers all individuals as belonging to the same “average” species, i.e., without a description of diversity. The second model introduces diversity by further considering individuals by a trait, here asymptotic...

  1. Exploring Critical Factors of Self Concept among High Income Community College Graduates

    Science.gov (United States)

    Rasul, Mohamad Sattar; Nor, Ahmad Rosli Mohd; Amat, Salleh; Rauf, Rose Amnah Abdul

    2015-01-01

    This study was undertaken to explore the critical factors influencing the self-concept of community college graduates in the development of their careers. Individuals with a positive self-concept are often associated with a good career choices and a well-panned career development path. Hence community college students should be girded with a…

  2. Optimal design and tuning of novel fractional order PID power system stabilizer using a new metaheuristic Bat algorithm

    Directory of Open Access Journals (Sweden)

    Lakhdar Chaib

    2017-06-01

    Full Text Available This paper proposes a novel robust power system stabilizer (PSS, based on hybridization of fractional order PID controller (PIλDμ and PSS for optimal stabilizer (FOPID-PSS for the first time, using a new metaheuristic optimization Bat algorithm (BA inspired by the echolocation behavior to improve power system stability. The problem of FOPID-PSS design is transformed as an optimization problem based on performance indices (PI, including Integral Absolute Error (IAE, Integral Squared Error (ISE, Integral of the Time-Weighted Absolute Error (ITAE and Integral of Time multiplied by the Squared Error (ITSE, where, BA is employed to obtain the optimal stabilizer parameters. In order to examine the robustness of FOPID-PSS, it has been tested on a Single Machine Infinite Bus (SMIB power system under different disturbances and operating conditions. The performance of the system with FOPID-PSS controller is compared with a PID-PSS and PSS. Further, the simulation results obtained with the proposed BA based FOPID-PSS are compared with those obtained with FireFly algorithm (FFA based FOPID-PSS. Simulation results show the effectiveness of BA for FOPID-PSS design, and superior robust performance for enhancement power system stability compared to other with different cases.

  3. Optimal explicit strong stability preserving Runge–Kutta methods with high linear order and optimal nonlinear order

    KAUST Repository

    Gottlieb, Sigal

    2015-04-10

    High order spatial discretizations with monotonicity properties are often desirable for the solution of hyperbolic PDEs. These methods can advantageously be coupled with high order strong stability preserving time discretizations. The search for high order strong stability time-stepping methods with large allowable strong stability coefficient has been an active area of research over the last two decades. This research has shown that explicit SSP Runge-Kutta methods exist only up to fourth order. However, if we restrict ourselves to solving only linear autonomous problems, the order conditions simplify and this order barrier is lifted: explicit SSP Runge-Kutta methods of any linear order exist. These methods reduce to second order when applied to nonlinear problems. In the current work we aim to find explicit SSP Runge-Kutta methods with large allowable time-step, that feature high linear order and simultaneously have the optimal fourth order nonlinear order. These methods have strong stability coefficients that approach those of the linear methods as the number of stages and the linear order is increased. This work shows that when a high linear order method is desired, it may still be worthwhile to use methods with higher nonlinear order.

  4. Conformational stability and self-association equilibrium in biologics.

    Science.gov (United States)

    Clarkson, Benjamin R; Schön, Arne; Freire, Ernesto

    2016-02-01

    Biologics exist in equilibrium between native, partially denatured, and denatured conformational states. The population of any of these states is dictated by their Gibbs energy and can be altered by changes in physical and solution conditions. Some conformations have a tendency to self-associate and aggregate, an undesirable phenomenon in protein therapeutics. Conformational equilibrium and self-association are linked thermodynamic functions. Given that any associative reaction is concentration dependent, conformational stability studies performed at different protein concentrations can provide early clues to future aggregation problems. This analysis can be applied to the selection of protein variants or the identification of better formulation solutions. In this review, we discuss three different aggregation situations and their manifestation in the observed conformational equilibrium of a protein. Copyright © 2015 Elsevier Ltd. All rights reserved.

  5. Meaning-making intervention during breast or colorectal cancer treatment improves self-esteem, optimism, and self-efficacy.

    Science.gov (United States)

    Lee, Virginia; Robin Cohen, S; Edgar, Linda; Laizner, Andrea M; Gagnon, Anita J

    2006-06-01

    Existential issues often accompany a diagnosis of cancer and remain one aspect of psychosocial oncology care for which there is a need for focused, empirically tested interventions. This study examined the efficacy of a novel psychological intervention specifically designed to address existential issues through the use of meaning-making coping strategies on psychological adjustment to cancer. Eighty-two breast or colorectal cancer patients were randomly chosen to receive routine care (control group) or up to four sessions that explored the meaning of the emotional responses and cognitive appraisals of each individual's cancer experience within the context of past life events and future goals (experimental group). This paper reports the results from 74 patients who completed and returned pre- and post-test measures for self-esteem, optimism, and self-efficacy. After controlling for baseline scores, the experimental group participants demonstrated significantly higher levels of self-esteem, optimism, and self-efficacy compared to the control group. The results are discussed in light of the theoretical and clinical implications of meaning-making coping in the context of stress and illness.

  6. Networked Timetable Stability Improvement Based on a Bilevel Optimization Programming Model

    Directory of Open Access Journals (Sweden)

    Xuelei Meng

    2014-01-01

    Full Text Available Train timetable stability is the possibility to recover the status of the trains to serve as arranged according to the original timetable when the trains are disturbed. To improve the train timetable stability from the network perspective, the bilevel programming model is constructed, in which the upper level programming is to optimize the timetable stability on the network level and the lower is to improve the timetable stability on the dispatching railway segments. Timetable stability on the network level is defined with the variances of the utilization coefficients of the section capacity and station capacity. Weights of stations and sections are decided by the capacity index number and the degrees. The lower level programming focuses on the buffer time distribution plan of the trains operating on the sections and stations, taking the operating rules of the trains as constraints. A novel particle swarm algorithm is proposed and designed for the bilevel programming model. The computing case proves the feasibility of the model and the efficiency of the algorithm. The method outlined in this paper can be embedded in the networked train operation dispatching system.

  7. Does stability in local community composition depend on temporal variation in rates of dispersal and connectivity?

    Science.gov (United States)

    Valanko, Sebastian; Norkko, Joanna; Norkko, Alf

    2015-04-01

    In ecology understanding variation in connectivity is central for how biodiversity is maintained. Field studies on dispersal and temporal dynamics in community regulating processes are, however, rare. We test the short-term temporal stability in community composition in a soft-sediment benthic community by determining among-sampling interval similarity in community composition. We relate stability to in situ measures of connectivity (wind, wave, current energy) and rates of dispersal (quantified in different trap types). Waves were an important predictor of when local community taxa are most likely to disperse in different trap-types, suggesting that wave energy is important for connectivity in a region. Community composition at the site was variable and changed stochastically over time. We found changes in community composition (occurrence, abundance, dominance) to be greater at times when connectivity and rates of dispersal were low. In response to periods of lower connectedness dominant taxa in the local community only exhibited change in their relative abundance. In contrast, locally less abundant taxa varied in both their presence, as well as in relative abundance. Constancy in connectivity and rates of dispersal promotes community stability and persistence, suggesting that local community composition will be impacted by changes in the spatial extent over which immigration and emigration operates in the region. Few empirical studies have actually measured dispersal directly in a multi-species context to demonstrate the role it plays in maintaining local community structure. Even though our study does not evaluate coexistence over demographic time scales, it importantly demonstrates that dispersal is not only important in initial recruitment or following a disturbance, but also key in maintaining local community composition.

  8. Integrated optimization on aerodynamics-structure coupling and flight stability of a large airplane in preliminary design

    Directory of Open Access Journals (Sweden)

    Xiaozhe WANG

    2018-06-01

    Full Text Available The preliminary phase is significant during the whole design process of a large airplane because of its enormous potential in enhancing the overall performance. However, classical sequential designs can hardly adapt to modern airplanes, due to their repeated iterations, long periods, and massive computational burdens. Multidisciplinary analysis and optimization demonstrates the capability to tackle such complex design issues. In this paper, an integrated optimization method for the preliminary design of a large airplane is proposed, accounting for aerodynamics, structure, and stability. Aeroelastic responses are computed by a rapid three-dimensional flight load analysis method combining the high-order panel method and the structural elasticity correction. The flow field is determined by the viscous/inviscid iteration method, and the cruise stability is evaluated by the linear small-disturbance theory. Parametric optimization is carried out using genetic algorithm to seek the minimal weight of a simplified plate-beam wing structure in the cruise trim condition subject to aeroelastic, aerodynamic, and stability constraints, and the optimal wing geometry shape, front/rear spar positions, and structural sizes are obtained simultaneously. To reduce the computational burden of the static aeroelasticity analysis in the optimization process, the Kriging method is employed to predict aerodynamic influence coefficient matrices of different aerodynamic shapes. The multidisciplinary analyses guarantee computational accuracy and efficiency, and the integrated optimization considers the coupling effect sufficiently between different disciplines to improve the overall performance, avoiding the limitations of sequential approaches utilized currently. Keywords: Aeroelasticity, Integrated optimization, Multidisciplinary analysis, Large airplane, Preliminary design

  9. Discrete particle swarm optimization for identifying community structures in signed social networks.

    Science.gov (United States)

    Cai, Qing; Gong, Maoguo; Shen, Bo; Ma, Lijia; Jiao, Licheng

    2014-10-01

    Modern science of networks has facilitated us with enormous convenience to the understanding of complex systems. Community structure is believed to be one of the notable features of complex networks representing real complicated systems. Very often, uncovering community structures in networks can be regarded as an optimization problem, thus, many evolutionary algorithms based approaches have been put forward. Particle swarm optimization (PSO) is an artificial intelligent algorithm originated from social behavior such as birds flocking and fish schooling. PSO has been proved to be an effective optimization technique. However, PSO was originally designed for continuous optimization which confounds its applications to discrete contexts. In this paper, a novel discrete PSO algorithm is suggested for identifying community structures in signed networks. In the suggested method, particles' status has been redesigned in discrete form so as to make PSO proper for discrete scenarios, and particles' updating rules have been reformulated by making use of the topology of the signed network. Extensive experiments compared with three state-of-the-art approaches on both synthetic and real-world signed networks demonstrate that the proposed method is effective and promising. Copyright © 2014 Elsevier Ltd. All rights reserved.

  10. Extension and customization of self-stability control in compliant legged systems

    International Nuclear Information System (INIS)

    Ernst, M; Blickhan, R; Geyer, H

    2012-01-01

    Several recent studies on the control of legged locomotion in animal and robot running focus on the influence of different leg parameters on gait stability. In a preceding investigation self-stability controls showing deadbeat behavior could be obtained by studying the dynamics of the system in dependence of the leg orientation carefully adjusted during the flight phase. Such controls allow to accommodate disturbances of the ground level without having to detect them. Here we further this method in two ways. Besides the leg orientation, we allow changes in leg stiffness during flight and show that this extension substantially improves the rejection of ground disturbances. In a human like example the tolerance of random variation in ground level over many steps increased from 3.5% to 35% of leg length. In single steps changes of about 70% leg length (either up or down) could be negotiated. The variable leg stiffness not only allows to start with flat leg orientations maximizing step tolerances but also increase the control subspace. This allows to customize self-stability controls and to consider physical and technical limitations found in animals and robots. (paper)

  11. IDP STABILIZATION ASSISTANCE: ROUTES TO OPTIMIZATION IN UKRAINE

    Directory of Open Access Journals (Sweden)

    Yuliia Zavadovska

    2016-11-01

    Full Text Available The purpose of the paper is to advise to optimization improvement pathways in IDP stabilization system in Ukraine that currently lacks real-time global-scale coordination, resulting in less efficient peaceful change. It is argued that with funding uncertainty, the system halts at middle level, aiming at sustainability. The article states that to improve, it needs to maintain high motivation and marketability of its professionals through skills and professional certification. Future grassroots projects should focus on mind changes. Methodology. A desk and in-depth study has been carried out of several national IDP stabilization programs dealing with the government that ensure infrastructural support to communities hosting IDPs. It has been studied how the programs “mindchange” their stakeholders (2014-2016 data via regional NGOs and supports grassroots, using a real-time communication platform with features of cloud, internet banking, social network and dedicated server. Improving change generation tools, it leverages transformation with small, but not too small, resources to catalyze change. Results of the research showed that the bargain between external priorities and grassroots interests should favor program interest with “soft” projects, and listen to grassroots with “hard” projects. However, funding for non-state actors could have a 4–level structure, including: national projects for regional change strategies; regional NGO support funds; simple grassroots grants; and individual innovation prizes. Practical implications. Regional NGOs can improve beneficiary satisfaction and widen participation by supporting informal civic movements. For slowlyfunded programs, a pre-funding risk assessment report could be useful to assess change that is happening before the funding starts. Additionally, internships as a mind changing tool in IDP perception should focus on young professionals and high-ranked MPs, the latter to be engaged in

  12. Evaluating the Stability of Feature Selectors that Optimize Feature Subset Cardinality

    Czech Academy of Sciences Publication Activity Database

    Somol, Petr; Novovičová, Jana

    2008-01-01

    Roč. 2008, č. 5342 (2008), s. 956-966 ISSN 0302-9743. [Joint IAPR International Workshops SSPR 2008 and SPR 2008. Orlando , 04.12.2008-06.12.2008] R&D Projects: GA AV ČR 1ET400750407; GA MŠk 1M0572; GA ČR GA102/07/1594 Grant - others:GA MŠk(CZ) 2C06019 Institutional research plan: CEZ:AV0Z10750506 Keywords : Feature selection * stability * relative weighted consistency measure * sequential search * floating search Subject RIV: IN - Informatics, Computer Science http://library.utia.cas.cz/separaty/2008/RO/somol-evaluating the stability of feature selectors that optimize feature subset cardinality.pdf

  13. The Self-Concept of Students in Remediation in a Rural Community College in Mississippi

    Science.gov (United States)

    Wicks, Corky Fitzgerald

    2017-01-01

    Identifying students who may require additional assistance and coaching based on their self-concept score will also allow community colleges to provide additional support services for those students. If there is a difference in self-concept among students in a Mississippi community college, leaders might be able to use self-concept as a way of…

  14. Multi-machine power system stabilizers design using chaotic optimization algorithm

    Energy Technology Data Exchange (ETDEWEB)

    Shayeghi, H., E-mail: hshayeghi@gmail.co [Technical Engineering Department, University of Mohaghegh Ardabili, Ardabil (Iran, Islamic Republic of); Shayanfar, H.A. [Center of Excellence for Power System Automation and Operation, Electrical Engineering Department, Iran University of Science and Technology, Tehran (Iran, Islamic Republic of); Jalilzadeh, S.; Safari, A. [Technical Engineering Department, Zanjan University, Zanjan (Iran, Islamic Republic of)

    2010-07-15

    In this paper, a multiobjective design of the multi-machine power system stabilizers (PSSs) using chaotic optimization algorithm (COA) is proposed. Chaotic optimization algorithms, which have the features of easy implementation, short execution time and robust mechanisms of escaping from the local optimum, is a promising tool for the engineering applications. The PSSs parameters tuning problem is converted to an optimization problem which is solved by a chaotic optimization algorithm based on Lozi map. Since chaotic mapping enjoys certainty, ergodicity and the stochastic property, the proposed chaotic optimization problem introduces chaos mapping using Lozi map chaotic sequences which increases its convergence rate and resulting precision. Two different objective functions are proposed in this study for the PSSs design problem. The first objective function is the eigenvalues based comprising the damping factor, and the damping ratio of the lightly damped electro-mechanical modes, while the second is the time domain-based multi-objective function. The robustness of the proposed COA-based PSSs (COAPSS) is verified on a multi-machine power system under different operating conditions and disturbances. The results of the proposed COAPSS are demonstrated through eigenvalue analysis, nonlinear time-domain simulation and some performance indices. In addition, the potential and superiority of the proposed method over the classical approach and genetic algorithm is demonstrated.

  15. Reactive power dispatch considering voltage stability with seeker optimization algorithm

    Energy Technology Data Exchange (ETDEWEB)

    Dai, Chaohua; Chen, Weirong; Zhang, Xuexia [The School of Electrical Engineering, Southwest Jiaotong University, Chengdu 610031 (China); Zhu, Yunfang [Department of Computer and Communication Engineering, E' mei Campus, Southwest Jiaotong University, E' mei 614202 (China)

    2009-10-15

    Optimal reactive power dispatch (ORPD) has a growing impact on secure and economical operation of power systems. This issue is well known as a non-linear, multi-modal and multi-objective optimization problem where global optimization techniques are required in order to avoid local minima. In the last decades, computation intelligence-based techniques such as genetic algorithms (GAs), differential evolution (DE) algorithms and particle swarm optimization (PSO) algorithms, etc., have often been used for this aim. In this work, a seeker optimization algorithm (SOA) based method is proposed for ORPD considering static voltage stability and voltage deviation. The SOA is based on the concept of simulating the act of human searching where search direction is based on the empirical gradient by evaluating the response to the position changes and step length is based on uncertainty reasoning by using a simple Fuzzy rule. The algorithm's performance is studied with comparisons of two versions of GAs, three versions of DE algorithms and four versions of PSO algorithms on the IEEE 57 and 118-bus power systems. The simulation results show that the proposed approach performed better than the other listed algorithms and can be efficiently used for the ORPD problem. (author)

  16. Tinkering and Technical Self-Efficacy of Engineering Students at the Community College

    Science.gov (United States)

    Baker, Dale R.; Wood, Lorelei; Corkins, James; Krause, Stephen

    2015-01-01

    Self-efficacy in engineering is important because individuals with low self-efficacy have lower levels of achievement and persistence in engineering majors. To examine self-efficacy among community college engineering students, an instrument to specifically measure two important aspects of engineering, tinkering and technical self-efficacy, was…

  17. Root Growth Optimizer with Self-Similar Propagation

    Directory of Open Access Journals (Sweden)

    Xiaoxian He

    2015-01-01

    Full Text Available Most nature-inspired algorithms simulate intelligent behaviors of animals and insects that can move spontaneously and independently. The survival wisdom of plants, as another species of biology, has been neglected to some extent even though they have evolved for a longer period of time. This paper presents a new plant-inspired algorithm which is called root growth optimizer (RGO. RGO simulates the iterative growth behaviors of plant roots to optimize continuous space search. In growing process, main roots and lateral roots, classified by fitness values, implement different strategies. Main roots carry out exploitation tasks by self-similar propagation in relatively nutrient-rich areas, while lateral roots explore other places to seek for better chance. Inhibition mechanism of plant hormones is applied to main roots in case of explosive propagation in some local optimal areas. Once resources in a location are exhausted, roots would shrink away from infertile conditions to preserve their activity. In order to validate optimization effect of the algorithm, twelve benchmark functions, including eight classic functions and four CEC2005 test functions, are tested in the experiments. We compared RGO with other existing evolutionary algorithms including artificial bee colony, particle swarm optimizer, and differential evolution algorithm. The experimental results show that RGO outperforms other algorithms on most benchmark functions.

  18. Artificial neural network with self-organizing mapping for reactor stability monitoring

    International Nuclear Information System (INIS)

    Okumura, Motofumi; Tsuji, Masashi; Shimazu, Yoichiro

    2009-01-01

    In boiling water reactor (BWR) stability monitoring, damping ratio has been used as a stability index. A method for estimating the damping ratio by applying Principal Component Analysis (PCA) to neutron detector signals measured with local power range monitors (LPRMs) had been developed; in this method, measured fluctuating signal is decomposed into some independent components and the signal components directly related to stability are extracted among them to determine the damping ratio. For online monitoring, it is necessary to select stability related signal components efficiently. The self-organizing map (SOM) is one of the artificial neural networks (ANNs) and has the characteristics such that online learning is possible without supervised learning within a relatively short time. In the present study, the SOM was applied to extract the relevant signal components more quickly and more accurately, and the availability was confirmed through the feasibility study. For realizing online stability monitoring only with ANNs, another type of ANN that performs online processing of PCA was combined with SOM. And stability monitoring performance was investigated. (author)

  19. How plants connect pollination and herbivory networks and their contribution to community stability.

    Science.gov (United States)

    Sauve, Alix M C; Thébault, Elisa; Pocock, Michael J O; Fontaine, Colin

    2016-04-01

    Pollination and herbivory networks have mainly been studied separately, highlighting their distinct structural characteristics and the related processes and dynamics. However, most plants interact with both pollinators and herbivores, and there is evidence that both types of interaction affect each other. Here we investigated the way plants connect these mutualistic and antagonistic networks together, and the consequences for community stability. Using an empirical data set, we show that the way plants connect pollination and herbivory networks is not random and promotes community stability. Analyses of the structure of binary and quantitative networks show different results: the plants' generalism with regard to pollinators is positively correlated to their generalism with regard to herbivores when considering binary interactions, but not when considering quantitative interactions. We also show that plants that share the same pollinators do not share the same herbivores. However, the way plants connect pollination and herbivory networks promotes stability for both binary and quantitative networks. Our results highlight the relevance of considering the diversity of interaction types in ecological communities, and stress the need to better quantify the costs and benefits of interactions, as well as to develop new metrics characterizing the way different interaction types are combined within ecological networks.

  20. The Effects of Pilates Training on Balance Control and Self-Reported Health Status in Community-Dwelling Older Adults: A Randomized Controlled Trial.

    Science.gov (United States)

    Gabizon, Hadas; Press, Yan; Volkov, Ilia; Melzer, Itshak

    2016-07-01

    To evaluate the effect of a group-based Pilates training program on balance control and health status in healthy older adults. A single-blind, randomized, controlled trial. General community. A total of 88 community-dwelling older adults (age 71.15 ± 4.30 years), without evidence of functional balance impairment, were recruited and allocated at random to a Pilates intervention group (n = 44) or a control group (n = 44). The Pilates intervention group received 36 training sessions over three months (3 sessions a week), while the control group did not receive any intervention. Standing upright postural stability, performance-based measures of balance, and self-reported health status was assessed in both groups at baseline and at the end of the intervention period. Compared with the control group, the Pilates intervention did not improve postural stability, baseline functional measures of balance, or health status. The results suggest that because Pilates training is not task specific, it does not improve balance control or balance function in independent older adults.

  1. Artificial neural network with self-organizing mapping for reactor stability monitoring

    International Nuclear Information System (INIS)

    Okumura, Motofumi; Tsuji, Masashi; Shimazu, Yoichiro; Narabayashi, Tadashi

    2008-01-01

    In BWR stability monitoring damping ratio has been used as a stability index. A method for estimating the damping ratio by applying Principal Component Analysis (PCA) to neutron detector signals measured with local power range monitors (LPRMs) had been developed; In this method, measured fluctuating signal is decomposed into some independent components and the signal component directly related to stability is extracted among them to determine the damping ratio. For online monitoring, it is necessary to select stability related signal component efficiently. The self-organizing map (SOM) is one of the artificial neural networks and has the characteristics such that online learning is possible without supervised learning within a relatively short time. In the present study, the SOM was applied to extract the relevant signal component more quickly and more accurately, and the availability was confirmed through the feasibility study. (author)

  2. Optimism, self-efficiency and self-concept: Why some students expect greater academic success than others?

    Directory of Open Access Journals (Sweden)

    Sabina Bele

    2009-07-01

    Full Text Available The purpose of our research was to examine the relation between academic success and constructs: optimism, self-efficiency, and self-concept. We also wanted to examine how this relation reflects in previous and future marks of fourth-grade highschool students. We predicted that students with higher academic success in specific fields will also have higher specific self-concept, which reflects characteristic competence. We also predicted that more optimistic, more self-efficient students and students with higher self-concept will set up higher future goals, because they see desired goals as attainable and are persistent in reaching their goals. One-hundred students filled in the Self-Description Questionnire III (SDQIII, the Life Orientation Test-Revised (LOT-R, the Generalized Self-Efficacy Scale (GSE, and stated marks of their previous grade, present marks (Slovenian language, mathematics, and foreign language and anticipated marks at graduation. The results confirmed our expectations: Students with higher marks on different subjects in previous grade also had higher specific self-concept, and more optimistic and self-efficient students with higher self-concept set up higher future goals.

  3. Optimizing Classroom Instruction through Self-Paced Learning Prototype

    Science.gov (United States)

    Bautista, Romiro G.

    2015-01-01

    This study investigated the learning impact of self-paced learning prototype in optimizing classroom instruction towards students' learning in Chemistry. Two sections of 64 Laboratory High School students in Chemistry were used as subjects of the study. The Quasi-Experimental and Correlation Research Design was used in the study: a pre-test was…

  4. Effects of Self-esteem, Optimism, and Perceived Control on Depressive Symptoms in Stroke Survivor-Spouse Dyads.

    Science.gov (United States)

    Chung, Misook L; Bakas, Tamilyn; Plue, Laura D; Williams, Linda S

    2016-01-01

    Depressive symptoms are common in stroke survivors and their family caregivers. Given the interdependent relationship between the members of dyads in poststroke management, improving depressive symptoms in dyads may depend on their partner's characteristics. Self-esteem, optimism, and perceived control, all known to be associated with depressive symptoms in an individual, may also contribute to their partner's depressive symptoms. The purpose of this study is to examine actor and partner effects of self-esteem, optimism, and perceived control on depression in stroke survivors and their spousal caregivers. A total of 112 ischemic stroke survivors (78% white, 34% women; mean age, 62.5 ± 12.3 years) and their spouses (mean age, 60.6 ± 12.9 years) completed surveys in which depressive symptoms, self-esteem, optimism, and perceived control were assessed using the Patient Health Questionnaire, the Rosenberg Self-esteem Scale, the Revised Life Orientation Test, and the Sense of Control Scale. Multilevel modeling, actor-partner interdependence model regression was used to determine influences on depressive symptoms within the dyad. Individuals with lower self-esteem, optimism, and perceived control had higher levels of depressive symptoms. Stroke survivors whose spouses had lower levels of self-esteem (B = -0.338, P self-esteem (B = -0.047, P = .036) also had higher levels of depressive symptoms. We found significant partner effects of self-esteem on depression for both members and partner effect of optimism on patient's depressive symptoms. These findings suggest that further research is needed to determine if dyadic interventions may help to improve self-esteem, optimism, and depressive symptoms in both patients and their caregivers.

  5. Robust optimal self tuning regulator of nuclear reactors

    International Nuclear Information System (INIS)

    Nouri Khajavi, M.; Menhaj, M.B.; Ghofrani, M.B.

    2000-01-01

    Nuclear power reactors are, in nature nonlinear and time varying. These characteristics must be considered, if large power variations occur in their working regime. In this paper a robust optimal self-tuning regulator for regulating the power of a nuclear reactor has been designed and simulated. The proposed controller is capable of regulating power levels in a wide power range (10% to 100% power levels). The controller achieves a fast and good transient response. The simulation results show that the proposed controller outperforms the fixed optimal control recently cited in the literature for nuclear power plants

  6. Information spread in networks: Games, optimal control, and stabilization

    Science.gov (United States)

    Khanafer, Ali

    This thesis focuses on designing efficient mechanisms for controlling information spread in networks. We consider two models for information spread. The first one is the well-known distributed averaging dynamics. The second model is a nonlinear one that describes virus spread in computer and biological networks. We seek to design optimal, robust, and stabilizing controllers under practical constraints. For distributed averaging networks, we study the interaction between a network designer and an adversary. We consider two types of attacks on the network. In Attack-I, the adversary strategically disconnects a set of links to prevent the nodes from reaching consensus. Meanwhile, the network designer assists the nodes in reaching consensus by changing the weights of a limited number of links in the network. We formulate two problems to describe this competition where the order in which the players act is reversed in the two problems. Although the canonical equations provided by the Pontryagin's Maximum Principle (MP) seem to be intractable, we provide an alternative characterization for the optimal strategies that makes connection to potential theory. Further, we provide a sufficient condition for the existence of a saddle-point equilibrium (SPE) for the underlying zero-sum game. In Attack-II, the designer and the adversary are both capable of altering the measurements of all nodes in the network by injecting global signals. We impose two constraints on both players: a power constraint and an energy constraint. We assume that the available energy to each player is not sufficient to operate at maximum power throughout the horizon of the game. We show the existence of an SPE and derive the optimal strategies in closed form for this attack scenario. As an alternative to the "network designer vs. adversary" framework, we investigate the possibility of stabilizing unknown network diffusion processes using a distributed mechanism, where the uncertainty is due to an attack

  7. Optimal Allocation of Wind Turbines by Considering Transmission Security Constraints and Power System Stability

    Directory of Open Access Journals (Sweden)

    Rodrigo Palma-Behnke

    2013-01-01

    Full Text Available A novel optimization methodology consisting of finding the near optimal location of wind turbines (WTs on a planned transmission network in a secure and cost-effective way is presented on this paper. While minimizing the investment costs of WTs, the algorithm allocates the turbines so that a desired wind power energy-penetration level is reached. The optimization considers both transmission security and power system stability constraints. The results of the optimization provide regulators with a support instrument to give proper signals to WT investors, in order to achieve secure and cost effective wind power network integration. The proposal is especially aimed at countries in the initial stage of wind power development, where the WT network integration process can still be influenced by policy-makers. The proposed methodology is validated with a real power system. Obtained results are compared with those generated from a business-as-usual (BAU scenario, in which the WT network allocation is made according to existing WT projects. The proposed WT network allocation scheme not only reduces the total investment costs associated with a determined wind power energy target, but also improves power system stability.

  8. Emotional Responsiveness and Emotional Stability in Three Religious Communities of India.

    Science.gov (United States)

    Prakash, Jai; Shukla, Anand Prakash

    The present study investigated personality dispositions such as emotional responsiveness and emotional stability in religious communities of India. The religious ideology and particular system of religious practices of each individual may influence his personality structure. A review of the literature shows that studies available in this area have…

  9. Relationships between Academic Stress, Social Support, Optimism-Pessimism and Self-Esteem in College Students

    Science.gov (United States)

    Fernández-González, L.; González-Hernández, A.; Trianes-Torres, M. V.

    2015-01-01

    Introduction: This research aims to analyse how optimism, self-esteem and social support help to predict academic stress. Method: The sample consisted of 123 students aged 20 to 31 years old, from the 3rd Year in the Psychology Degree. Students completed the Rosenberg Self-esteem Scale, the Life Orientation Optimism Questionnaire (LOT-R), the…

  10. Optimal self-esteem is contingent: Intrinsic versus extrinsic and upward versus downward contingencies

    NARCIS (Netherlands)

    Vonk, R.; Smit, H.M.M.

    2012-01-01

    We argue that noncontingent, unconditional self-esteem is not optimal but defensive. We introduce the concept of intrinsic contingency, where self-esteem is affected by whether one's actions are self-congruent and conducive to personal growth. Whereas external contingencies, especially social and

  11. COMPLEXITY OF ECOLOGICAL SYSTEMS (THE CASE OF MARINE CILIATE COMMUNITY

    Directory of Open Access Journals (Sweden)

    I.V. Burkovsky

    2016-03-01

    Full Text Available The paper analyzes the seasonal and long-term dynamics of marine interstitial ciliates communities as a result of the processes of system self-organization (of increasing complexity in constantly fluctuating environment. The traits of simple structure of ciliate community include substantial variability in the composition (even in case of stable environment and the lack of sustainable combinations of species. The mechanism of the current state maintenance is the lack of energy supply in certain periods or in specific loci of space, as well as large amplitude and unpredictable fluctuations of environmental factors. An indication of the community’s complexity is availability of stable combinations of species in time and space. The mechanisms of formation of stable species combinations are a constant flow of external energy, optimal values and stability of environmental factors (including repeatability of seasonal cycles and the use of space resources by species according the principle of complementarity of ecological niches.

  12. Biodiversity links above and below the marine sediment-water interface that may influence community stability

    NARCIS (Netherlands)

    Austen, M.C.; Lambshead, P.J.D.; Hutchings, P.; Boucher, G.; Snelgrove, P.V.R.; Heip, C.H.R.; King, G.; Koike, I.; Smith, C.

    2002-01-01

    Linkages across the sediment-water interface (SWI) between biodiversity and community stability appear to exist but are very poorly studied. Processes by which changes in biodiversity could affect stability on the other side of the SWI include carbon transfer during feeding, decomposition of organic

  13. Improved helicopter aeromechanical stability analysis using segmented constrained layer damping and hybrid optimization

    Science.gov (United States)

    Liu, Qiang; Chattopadhyay, Aditi

    2000-06-01

    Aeromechanical stability plays a critical role in helicopter design and lead-lag damping is crucial to this design. In this paper, the use of segmented constrained damping layer (SCL) treatment and composite tailoring is investigated for improved rotor aeromechanical stability using formal optimization technique. The principal load-carrying member in the rotor blade is represented by a composite box beam, of arbitrary thickness, with surface bonded SCLs. A comprehensive theory is used to model the smart box beam. A ground resonance analysis model and an air resonance analysis model are implemented in the rotor blade built around the composite box beam with SCLs. The Pitt-Peters dynamic inflow model is used in air resonance analysis under hover condition. A hybrid optimization technique is used to investigate the optimum design of the composite box beam with surface bonded SCLs for improved damping characteristics. Parameters such as stacking sequence of the composite laminates and placement of SCLs are used as design variables. Detailed numerical studies are presented for aeromechanical stability analysis. It is shown that optimum blade design yields significant increase in rotor lead-lag regressive modal damping compared to the initial system.

  14. Improving hypertension self-management with community health coaches.

    Science.gov (United States)

    Dye, Cheryl J; Williams, Joel E; Evatt, Janet Hoffman

    2015-03-01

    Approximately two thirds of those older than 60 years have a hypertension diagnosis. The aim of our program, Health Coaches for Hypertension Control, is to improve hypertension self-management among rural residents older than 60 years through education and support offered by trained community volunteers called Health Coaches. Participants received baseline and follow-up health risk appraisals with blood work, educational materials, and items such as blood pressure monitors and pedometers. Data were collected at baseline, 8 weeks, and 16 weeks on 146 participants who demonstrated statistically significant increases in hypertension-related knowledge from baseline to 8 weeks that persisted at 16 weeks, as well as significant improvements in stage of readiness to change behaviors and in actual behaviors. Furthermore, clinically significant decreases in all outcome measures were observed, with statistically significant changes in systolic blood pressure (-5.781 mmHg; p = .001), weight (-2.475 lb; p definition of controlled hypertension at baseline, the proportion of participants meeting this definition at 16 weeks postintervention increased to 51.0%. This article describes a university-community-hospital system model that effectively promotes hypertension self-management in a rural Appalachian community. © 2014 Society for Public Health Education.

  15. Primary stability of a hybrid self-tapping implant compared to a cylindrical non-self-tapping implant with respect to drilling protocols in an ex vivo model.

    Science.gov (United States)

    Toyoshima, Takeshi; Wagner, Wilfried; Klein, Marcus Oliver; Stender, Elmar; Wieland, Marco; Al-Nawas, Bilal

    2011-03-01

    Modifications of implant design have been intending to improve primary stability. However, little is known about investigation of a hybrid self-tapping implant on primary stability. The aims of this study were to evaluate the primary stability of two hybrid self-tapping implants compared to one cylindrical non-self-tapping implant, and to elucidate the relevance of drilling protocols on primary stability in an ex vivo model. Two types of hybrid self-tapping implants (Straumann® Bone Level implant [BL], Straumann® Tapered Effect implant [TE]) and one type of cylindrical non-self-tapping implant (Straumann® Standard Plus implant [SP]) were investigated in the study. In porcine iliac cancellous bones, 10 implants each were inserted either using standard drilling or under-dimensioned drilling protocol. The evaluation of implant-bone interface stability was carried out by records of maximum insertion torque, the Periotest® (Siemens, Bensheim, Germany), the resonance frequency analysis (RFA), and the push-out test. In each drilling group, the maximum insertion torque values of BL and TE were significantly higher than SP (p=.014 and p=.047, respectively). In each group, the Periotest values of TE were significantly lower than SP (p=.036 and p=.033, respectively). The Periotest values of BL and TE were significantly lower in the group of under-dimensioned drilling than standard drilling (p=.002 and p=.02, respectively). In the RFA, no statistical significances were found in implants between two groups and between implants in each group. In each group, the push-out values of BL and TE were significantly higher than SP (p=.006 and p=.049, respectively). Hybrid self-tapping implants could achieve a high primary stability which predicts them for use in low-density bone. However, there is still a debate to clarify the influence of under-dimensioned drilling on primary stability. © 2009, Copyright the Authors. Journal Compilation © 2011, Wiley Periodicals, Inc.

  16. Optimal Design of a Hydrogen Community by Genetic Algorithms

    International Nuclear Information System (INIS)

    Rodolfo Dufo Lopez; Jose Luis Bernal Agustin; Luis Correas Uson; Ismael Aso Aguarta

    2006-01-01

    A study was conducted for the implementation of two Hydrogen Communities, following the recommendations of the HY-COM initiative of the European Commission. The proposed communities find their place in the municipality of Sabinanigo (Aragon, Spain). Two cases are analyzed, one off-grid village house near Sabinanigo, and a house situated in the town proper. The study was carried out with the HOGA program, Hybrid Optimization by Genetic Algorithms. A description is provided for the algorithms. The off-grid study deals with a hybrid pv-wind system with hydrogen storage for AC supply to an isolated house. The urban study is related to hydrogen production by means of hybrid renewable sources available locally (photovoltaic, wind and hydro). These complement the existing industrial electrolysis processes, in order to cater for the energy requirements of a small fleet of municipal hydrogen-powered vehicles. HOGA was used to optimize both hybrid systems. Dimensioning and deployment estimations are also provided. (authors)

  17. Optimal Design of a Hydrogen Community by Genetic Algorithms

    International Nuclear Information System (INIS)

    Rodolfo Dufo Lopeza; Jose Luis Bernal Agustin; Luis Correas Uson; Ismael Aso Aguarta

    2006-01-01

    A study was conducted for the implementation of two Hydrogen Communities, following the recommendations of the HY-COM initiative of the European Commission. The proposed communities find their place in the municipality of Sabinanigo (Aragon, Spain). Two cases are analyzed, one off-grid village house near Sabinanigo, and a house situated in the town proper. The study was carried out with the HOGA program, Hybrid Optimization by Genetic Algorithms. A description is provided for the algorithms. The off-grid study deals with a hybrid PV-wind system with hydrogen storage for AC supply to an isolated house. The urban study is related to hydrogen production by means of hybrid renewable sources available locally (photovoltaic, wind and hydro). These complement the existing industrial electrolysis processes, in order to cater for the energy requirements of a small fleet of municipal hydrogen-powered vehicles. HOGA was used to optimize both hybrid systems. Dimensioning and deployment estimations are also provided. (authors)

  18. Stability and responsiveness in a self-organized living architecture.

    Directory of Open Access Journals (Sweden)

    Simon Garnier

    Full Text Available Robustness and adaptability are central to the functioning of biological systems, from gene networks to animal societies. Yet the mechanisms by which living organisms achieve both stability to perturbations and sensitivity to input are poorly understood. Here, we present an integrated study of a living architecture in which army ants interconnect their bodies to span gaps. We demonstrate that these self-assembled bridges are a highly effective means of maintaining traffic flow over unpredictable terrain. The individual-level rules responsible depend only on locally-estimated traffic intensity and the number of neighbours to which ants are attached within the structure. We employ a parameterized computational model to reveal that bridges are tuned to be maximally stable in the face of regular, periodic fluctuations in traffic. However analysis of the model also suggests that interactions among ants give rise to feedback processes that result in bridges being highly responsive to sudden interruptions in traffic. Subsequent field experiments confirm this prediction and thus the dual nature of stability and flexibility in living bridges. Our study demonstrates the importance of robust and adaptive modular architecture to efficient traffic organisation and reveals general principles regarding the regulation of form in biological self-assemblies.

  19. MHC I stabilizing potential of computer-designed octapeptides.

    Science.gov (United States)

    Wisniewska, Joanna M; Jäger, Natalie; Freier, Anja; Losch, Florian O; Wiesmüller, Karl-Heinz; Walden, Peter; Wrede, Paul; Schneider, Gisbert; Hiss, Jan A

    2010-01-01

    Experimental results are presented for 180 in silico designed octapeptide sequences and their stabilizing effects on the major histocompatibility class I molecule H-2K(b). Peptide sequence design was accomplished by a combination of an ant colony optimization algorithm with artificial neural network classifiers. Experimental tests yielded nine H-2K(b) stabilizing and 171 nonstabilizing peptides. 28 among the nonstabilizing octapeptides contain canonical motif residues known to be favorable for MHC I stabilization. For characterization of the area covered by stabilizing and non-stabilizing octapeptides in sequence space, we visualized the distribution of 100,603 octapeptides using a self-organizing map. The experimental results present evidence that the canonical sequence motives of the SYFPEITHI database on their own are insufficient for predicting MHC I protein stabilization.

  20. MHC I Stabilizing Potential of Computer-Designed Octapeptides

    Directory of Open Access Journals (Sweden)

    Joanna M. Wisniewska

    2010-01-01

    Full Text Available Experimental results are presented for 180 in silico designed octapeptide sequences and their stabilizing effects on the major histocompatibility class I molecule H-2Kb. Peptide sequence design was accomplished by a combination of an ant colony optimization algorithm with artificial neural network classifiers. Experimental tests yielded nine H-2Kb stabilizing and 171 nonstabilizing peptides. 28 among the nonstabilizing octapeptides contain canonical motif residues known to be favorable for MHC I stabilization. For characterization of the area covered by stabilizing and non-stabilizing octapeptides in sequence space, we visualized the distribution of 100,603 octapeptides using a self-organizing map. The experimental results present evidence that the canonical sequence motives of the SYFPEITHI database on their own are insufficient for predicting MHC I protein stabilization.

  1. In-Well Sediment Incubators to Evaluate Microbial Community Stability and Dynamics following Bioimmobilization of Uranium

    International Nuclear Information System (INIS)

    Baldwin, Brett R.; Peacock, Aaron D.; Gan, M.; Resch, Charles T.; Arntzen, Evan V.; Smithgall, A.N.; Pfiffner, S.; Freifeld, Barry M.; White, D.C.; Long, Philip E.

    2009-01-01

    An in-situ incubation device (ISI) was developed in order to investigate the stability and dynamics of sediment associated microbial communities to prevailing subsurface oxidizing or reducing conditions. Here we describe the use of these devices at the Old Rifle Uranium Mill Tailings Remedial Action (UMTRA) site. During the 7 month deployment oxidized Rifle aquifer background sediments (RABS) were deployed in previously biostimulated wells under iron reducing conditions, cell densities of known iron reducing bacteria including Geobacteraceae increased significantly showing the microbial community response to local subsurface conditions. PLFA profiles of RABS following in situ deployment were strikingly similar to those of adjacent sediment cores suggesting ISI results could be extrapolated to the native material of the test plots. Results for ISI deployed reduced sediments showed only slight changes in community composition and pointed toward the ability of the ISIs to monitor microbial community stability and response to subsurface conditions.

  2. A Self-Stabilizing Hybrid Fault-Tolerant Synchronization Protocol

    Science.gov (United States)

    Malekpour, Mahyar R.

    2015-01-01

    This paper presents a strategy for solving the Byzantine general problem for self-stabilizing a fully connected network from an arbitrary state and in the presence of any number of faults with various severities including any number of arbitrary (Byzantine) faulty nodes. The strategy consists of two parts: first, converting Byzantine faults into symmetric faults, and second, using a proven symmetric-fault tolerant algorithm to solve the general case of the problem. A protocol (algorithm) is also present that tolerates symmetric faults, provided that there are more good nodes than faulty ones. The solution applies to realizable systems, while allowing for differences in the network elements, provided that the number of arbitrary faults is not more than a third of the network size. The only constraint on the behavior of a node is that the interactions with other nodes are restricted to defined links and interfaces. The solution does not rely on assumptions about the initial state of the system and no central clock nor centrally generated signal, pulse, or message is used. Nodes are anonymous, i.e., they do not have unique identities. A mechanical verification of a proposed protocol is also present. A bounded model of the protocol is verified using the Symbolic Model Verifier (SMV). The model checking effort is focused on verifying correctness of the bounded model of the protocol as well as confirming claims of determinism and linear convergence with respect to the self-stabilization period.

  3. Measuring and Examining General Self-Efficacy among Community College Students: A Structural Equation Modeling Approach

    Science.gov (United States)

    Chen, Yu; Starobin, Soko S.

    2018-01-01

    This study examined a psychosocial mechanism of how general self-efficacy interacts with other key factors and influences degree aspiration for students enrolled in an urban diverse community college. Using general self-efficacy scales, the authors hypothesized the General Self-efficacy model for Community College students (the GSE-CC model). A…

  4. Optimal Sizing of Energy Storage for Community Microgrids Considering Building Thermal Dynamics

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Guodong [ORNL; Li, Zhi [ORNL; Starke, Michael R. [ORNL; Ollis, Ben [ORNL; Tomsovic, Kevin [University of Tennessee, Knoxville (UTK)

    2017-07-01

    This paper proposes an optimization model for the optimal sizing of energy storage in community microgrids considering the building thermal dynamics and customer comfort preference. The proposed model minimizes the annualized cost of the community microgrid, including energy storage investment, purchased energy cost, demand charge, energy storage degradation cost, voluntary load shedding cost and the cost associated with customer discomfort due to room temperature deviation. The decision variables are the power and energy capacity of invested energy storage. In particular, we assume the heating, ventilation and air-conditioning (HVAC) systems can be scheduled intelligently by the microgrid central controller while maintaining the indoor temperature in the comfort range set by customers. For this purpose, the detailed thermal dynamic characteristics of buildings have been integrated into the optimization model. Numerical simulation shows significant cost reduction by the proposed model. The impacts of various costs on the optimal solution are investigated by sensitivity analysis.

  5. Community-based peer-led diabetes self-management: a randomized trial.

    Science.gov (United States)

    Lorig, Kate; Ritter, Philip L; Villa, Frank J; Armas, Jean

    2009-01-01

    The purpose of this study is to determine the effectiveness of a community-based diabetes self-management program comparing treatment participants to a randomized usual-care control group at 6 months. A total of 345 adults with type 2 diabetes but no criteria for high A1C were randomized to a usual-care control group or 6-week community-based, peer-led diabetes self-management program (DSMP). Randomized participants were compared at 6 months. The DSMP intervention participants were followed for an additional 6 months (12 months total). A1C and body mass index were measured at baseline, 6 months, and 12 months. All other data were collected by self-administered questionnaires. At 6 months, DSMP participants did not demonstrate improvements in A1C as compared with controls. Baseline A1C was much lower than in similar trials. Participants did have significant improvements in depression, symptoms of hypoglycemia, communication with physicians, healthy eating, and reading food labels (P < .01). They also had significant improvements in patient activation and self-efficacy. At 12 months, DSMP intervention participants continued to demonstrate improvements in depression, communication with physicians, healthy eating, patient activation, and self-efficacy (P < .01). There were no significant changes in utilization measures. These findings suggest that people with diabetes without elevated A1C can benefit from a community-based, peer-led diabetes program. Given the large number of people with diabetes and lack of low-cost diabetes education, the DSMP deserves consideration for implementation.

  6. Dyad conversations about self-stigma in two Scottish communities.

    Science.gov (United States)

    Mackay, Rob; Bradstreet, Simon; McArthur, Andy; Dunion, Linda

    2015-06-01

    This study explored self-stigma in 2 Scottish communities and strategies for challenging stigma and discrimination. A mixed-methods approach was used encompassing a survey including the Internalized Stigma of Mental Illness Inventory (ISMI) and facilitated dyad conversations with people with lived experience of mental illness. Self-reported experience of self-stigma across 2 communities was most closely associated with the ISMI Alienation cluster, accompanied by a high level of agreement with the Stigma Resistance cluster. Some 44% agreed that stereotypes about people with mental health problems applied to them, and almost 2/3 felt that having a mental health problem had spoiled their lives. Many participants reported reduced confidence, loss of hope, a sense of failure, and protecting oneself through social withdrawal. The findings also offer hope through narratives from people who have "pushed back" and are striving to reduce their own self-stigma by engaging with others and managing their own recovery journey. The journey through self-stigma and beyond has to be informed by what we know works with recovery from a mental health problem. At a policy and practice level, we recommend emphasis on 4 priorities: (a) refocusing antistigma and discrimination efforts more on the experiences of people who report stigma, (b) rights-based approaches, (c) identity-based work, and (d) information sharing and educational strategies. (c) 2015 APA, all rights reserved).

  7. Stabilization of microgrid with intermittent renewable energy sources by SMES with optimal coil size

    International Nuclear Information System (INIS)

    Saejia, M.; Ngamroo, I.

    2011-01-01

    A controller design of a superconducting magnetic energy storage unit is proposed. The structure of a power controller is the practical proportional-integral (PI). The PI parameters and coil size are tuned by a particle swarm optimization. The proposed method is able to effectively alleviate power fluctuations. It is well known that the superconducting coil is the vital part of a superconducting magnetic energy storage (SMES) unit. This paper deals with the power controller design of a SMES unit with an optimal coil size for stabilization of an isolated microgrid. The study microgrid consists of renewable energy sources with intermittent power outputs i.e., wind and photovoltaic. Since power generations from such renewable sources are unpredictable and variable, these result in power fluctuations in a microgrid. To stabilize power fluctuations, a SMES unit with a fast control of active and reactive power can be applied. The structure of a power controller is the practical proportional-integral (PI). Based on the minimization of the variance of power fluctuations from renewable sources as well as the initial stored energy of SMES, the optimal PI parameters and coil size are automatically and simultaneously tuned by a particle swarm optimization. Simulation studies show that the proposed SMES controller with an optimal coil size is able to effectively alleviate power fluctuations under various power patterns from intermittent renewable sources.

  8. Stabilization of microgrid with intermittent renewable energy sources by SMES with optimal coil size

    Energy Technology Data Exchange (ETDEWEB)

    Saejia, M., E-mail: samongkol@gmail.com [School of Electrical Engineering, Faculty of Engineering, King Mongkut' s Institute of Technology Ladkrabang, Bangkok 10520 (Thailand); Ngamroo, I. [School of Electrical Engineering, Faculty of Engineering, King Mongkut' s Institute of Technology Ladkrabang, Bangkok 10520 (Thailand)

    2011-11-15

    A controller design of a superconducting magnetic energy storage unit is proposed. The structure of a power controller is the practical proportional-integral (PI). The PI parameters and coil size are tuned by a particle swarm optimization. The proposed method is able to effectively alleviate power fluctuations. It is well known that the superconducting coil is the vital part of a superconducting magnetic energy storage (SMES) unit. This paper deals with the power controller design of a SMES unit with an optimal coil size for stabilization of an isolated microgrid. The study microgrid consists of renewable energy sources with intermittent power outputs i.e., wind and photovoltaic. Since power generations from such renewable sources are unpredictable and variable, these result in power fluctuations in a microgrid. To stabilize power fluctuations, a SMES unit with a fast control of active and reactive power can be applied. The structure of a power controller is the practical proportional-integral (PI). Based on the minimization of the variance of power fluctuations from renewable sources as well as the initial stored energy of SMES, the optimal PI parameters and coil size are automatically and simultaneously tuned by a particle swarm optimization. Simulation studies show that the proposed SMES controller with an optimal coil size is able to effectively alleviate power fluctuations under various power patterns from intermittent renewable sources.

  9. Self-help initiatives and rural development in Ibesikpo community of ...

    African Journals Online (AJOL)

    This study investigates the impact of self-help initiatives on rural development in Ibesikpo community of Akwa Ibom State, Nigeria. Self help initiatives were defined in terms of provision of employment, education and health-care. A sample size of 369 rural dwellers was drawn and data were analyzed using simple regression ...

  10. Development of a Self-Stabilizing Robotic Chassis for Industry

    Directory of Open Access Journals (Sweden)

    Ryadchikov Igor

    2017-01-01

    Full Text Available Presented the description of the bipedal robotic chassis with the unique kinematic scheme which has the possibility to locomote in complicated multi-level environment. AnyWalker is equipped with the system of compensation of external impacts with motor-wheels which can self-stabilize the robotic system in 3 dimensions. Presented chassis suggests to have open software and hardware architecture in order to become the universal walking platform for service and industry robots.

  11. Energy Optimization for Distributed Energy Resources Scheduling with Enhancements in Voltage Stability Margin

    DEFF Research Database (Denmark)

    Morais, Hugo; Sousa, Tiago; Perez, Angel

    2016-01-01

    to evaluate the resulting multiobjective optimization problem: the sum-weighted Pareto front and an adapted goal programming methodology. With this new methodology, the system operators can consider both the costs and voltage stability. Priority can be assigned to one objective function according...... to the operating scenario. Additionally, it is possible to evaluate the impact of the distributed generation and the electric vehicles in the management of voltage stability in the future electric networks. One detailed case study considering a distribution network with high penetration of distributed energy...

  12. Personality Stability from Childhood to Midlife: Relating Teachers’ Assessments in Elementary School to Observer- and Self-Ratings 40 Years Later

    Science.gov (United States)

    Edmonds, Grant W.; Goldberg, Lewis R.; Hampson, Sarah E.; Barckley, Maureen

    2013-01-01

    We report on the longitudinal stability of personality traits across an average 40 years in the Hawaii Personality and Health Cohort relating childhood teacher assessments of personality to adult self- and observer- reports. Stabilities based on self-ratings in adulthood were compared to those measured by the Structured Interview for the Five-Factor Model (SIFFM; Trull & Widiger, 1997), and trait ratings completed by interviewers. Although convergence between self-reports and observer-ratings was modest, childhood traits demonstrated similar levels of stability across methods in adulthood. Extraversion and Conscientiousness generally showed higher stabilities, whereas Neuroticism showed none. For Agreeableness and Intellect/Openness, stability was highest when assessed with observer-ratings. These findings are discussed in terms of differences in trait evaluativeness and observability across measurement methods. PMID:24039315

  13. Is type-D personality trait(s or state? An examination of type-D temporal stability in older Israeli adults in the community

    Directory of Open Access Journals (Sweden)

    Ada H. Zohar

    2016-02-01

    Full Text Available Background. Type D personality was suggested as a marker of poorer prognosis for patients of cardiovascular disease. It is defined by having a score of 10 or more on both sub-scales of the DS14 questionnaire, Social Inhibition (SI and Negative Affectivity (NA. As Type D was designed to predict risk, its temporal stability is of prime importance. Methods. Participants in the current study were 285 community volunteers, who completed the DS14, and other personality scales, at a mean interval of six years. Results. The prevalence of Type D did not change. The component traits of Type D showed rank order stability. Type D caseness temporal stability was improved by using the sub-scales product as a criterion. Logistic hierarchical regression predicting Type D classification from Time1 demonstrated that the best predictors were Time1 scores on NA and SI, with the character trait of Cooperation, and the alexithymia score adding some predictive power. Conclusions. The temporal stability of the component traits, and of the prevalence of Type D were excellent. Temporal stability of Type D caseness may be improved by using a product threshold, rather than the current rule. Research is required in order to formulate the optimal timing for Type D measurement for predictive purposes.

  14. Aminolysis of polyethylene terephthalate surface along with in situ synthesis and stabilizing ZnO nanoparticles using triethanolamine optimized with response surface methodology

    Energy Technology Data Exchange (ETDEWEB)

    Poortavasoly, Hajar; Montazer, Majid, E-mail: tex5mm@aut.ac.ir; Harifi, Tina

    2016-01-01

    This research concerned the simultaneous polyester surface modification and synthesis of zinc oxide nano-reactors to develop durable photo-bio-active fabric with variable hydrophobicity/hydrophilicity under sunlight. For this purpose, triethanolamine (TEA) was applied as a stabilizer and pH adjusting chemical for the aminolysis of polyester surface and enhancing the surface reactivity along with synthesis and deposition of ZnO nanoparticles on the fabric. Therefore, TEA played a crucial role in providing the alkaline condition for the preparation of zinc oxide nanoparticles and acting as stabilizer controlling the size of the prepared nanoparticles. The stain–photodegradability regarded as self-cleaning efficiency, wettability and weight change under the process was optimized based on zinc acetate and TEA concentrations, using central composite design (CCD). Findings also suggested the potential of the prepared fabric in inhibiting Staphylococcus aureus and Escherichia coli bacteria growth with greater than 99.99% antibacterial efficiency. Besides, the proposed treatment had no detrimental effect on tensile strength and hand feeling of the polyester fabric. - Highlights: • Durable photo-bio-active polyester with variable hydrophobicity/hydrophilicity • Simultaneous polyester surface aminolysis and ZnO ball-like nanoparticle production • Multi-role of TEA for polyester aminolysis and nanoparticle formation • Optimization of photoactivity and wettability by central composite design.

  15. First principles molecular dynamics without self-consistent field optimization

    International Nuclear Information System (INIS)

    Souvatzis, Petros; Niklasson, Anders M. N.

    2014-01-01

    We present a first principles molecular dynamics approach that is based on time-reversible extended Lagrangian Born-Oppenheimer molecular dynamics [A. M. N. Niklasson, Phys. Rev. Lett. 100, 123004 (2008)] in the limit of vanishing self-consistent field optimization. The optimization-free dynamics keeps the computational cost to a minimum and typically provides molecular trajectories that closely follow the exact Born-Oppenheimer potential energy surface. Only one single diagonalization and Hamiltonian (or Fockian) construction are required in each integration time step. The proposed dynamics is derived for a general free-energy potential surface valid at finite electronic temperatures within hybrid density functional theory. Even in the event of irregular functional behavior that may cause a dynamical instability, the optimization-free limit represents a natural starting guess for force calculations that may require a more elaborate iterative electronic ground state optimization. Our optimization-free dynamics thus represents a flexible theoretical framework for a broad and general class of ab initio molecular dynamics simulations

  16. Phytoplankton Diversity Effects on Community Biomass and Stability along Nutrient Gradients in a Eutrophic Lake

    Directory of Open Access Journals (Sweden)

    Wang Tian

    2017-01-01

    Full Text Available The relationship between biodiversity and ecosystem functioning is a central issue in ecology, but how this relationship is affected by nutrient stress is still unknown. In this study, we analyzed the phytoplankton diversity effects on community biomass and stability along nutrient gradients in an artificial eutrophic lake. Four nutrient gradients, varying from slightly eutrophic to highly eutrophic states, were designed by adjusting the amount of polluted water that flowed into the lake. Mean phytoplankton biomass, species richness, and Shannon diversity index all showed significant differences among the four nutrient gradients. Phytoplankton community biomass was correlated with diversity (both species richness and Shannon diversity index, varying from positive to negative along the nutrient gradients. The influence of phytoplankton species richness on resource use efficiency (RUE also changed from positive to negative along the nutrient gradients. However, the influence of phytoplankton Shannon diversity on RUE was not significant. Both phytoplankton species richness and Shannon diversity had a negative influence on community turnover (measured as community dissimilarity, i.e., a positive diversity–stability relationship. Furthermore, phytoplankton spatial stability decreased along the nutrient gradients in the lake. With increasing nutrient concentrations, the variability (standard deviation of phytoplankton community biomass increased more rapidly than the average total biomass. Results in this study will be helpful in understanding the phytoplankton diversity effects on ecosystem functioning and how these effects are influenced by nutrient conditions in aquatic ecosystems.

  17. Cyclic public goods games: Compensated coexistence among mutual cheaters stabilized by optimized penalty taxation

    Science.gov (United States)

    Griffin, Christopher; Belmonte, Andrew

    2017-05-01

    We study the problem of stabilized coexistence in a three-species public goods game in which each species simultaneously contributes to one public good while freeloading off another public good ("cheating"). The proportional population growth is governed by an appropriately modified replicator equation, depending on the returns from the public goods and the cost. We show that the replicator dynamic has at most one interior unstable fixed point and that the population becomes dominated by a single species. We then show that by applying an externally imposed penalty, or "tax" on success can stabilize the interior fixed point, allowing for the symbiotic coexistence of all species. We show that the interior fixed point is the point of globally minimal total population growth in both the taxed and untaxed cases. We then formulate an optimal taxation problem and show that it admits a quasilinearization, resulting in novel necessary conditions for the optimal control. In particular, the optimal control problem governing the tax rate must solve a certain second-order ordinary differential equation.

  18. Optimality and stability of symmetric evolutionary games with applications in genetic selection.

    Science.gov (United States)

    Huang, Yuanyuan; Hao, Yiping; Wang, Min; Zhou, Wen; Wu, Zhijun

    2015-06-01

    Symmetric evolutionary games, i.e., evolutionary games with symmetric fitness matrices, have important applications in population genetics, where they can be used to model for example the selection and evolution of the genotypes of a given population. In this paper, we review the theory for obtaining optimal and stable strategies for symmetric evolutionary games, and provide some new proofs and computational methods. In particular, we review the relationship between the symmetric evolutionary game and the generalized knapsack problem, and discuss the first and second order necessary and sufficient conditions that can be derived from this relationship for testing the optimality and stability of the strategies. Some of the conditions are given in different forms from those in previous work and can be verified more efficiently. We also derive more efficient computational methods for the evaluation of the conditions than conventional approaches. We demonstrate how these conditions can be applied to justifying the strategies and their stabilities for a special class of genetic selection games including some in the study of genetic disorders.

  19. Theoretical approach in optimization of stability of the multicomponent solid waste form

    International Nuclear Information System (INIS)

    Raicevic, S.; Plecas, I.; Mandic, M.

    1998-01-01

    Chemical precipitation of radionuclides and their immobilization into the solid matrix represents an important approach in the radioactive wastewater treatment. Unfortunately, because of the complexity of the system, optimization of this process in terms of its efficacy and safety represents a serious practical problem, even in treatment of the monocomponent nuclear waste. This situation is additionally complicated in the case of the polycomponent nuclear waste because of the synergic effects of interactions between the radioactive components and the solid matrix. Recently, we have proposed a general theoretical approach for optimization of the process of precipitation and immobilization of metal impurities by the solid matrix. One of the main advantages of this approach represents the possibility of treatment of the multicomponent liquid waste, immobilized by the solid matrix. This approach was used here for investigation of the stability of the system hydroxyapatite (HAP) - Pb/Cd, which was selected as a model multicomponent waste system. In this analysis, we have used a structurally dependent term of the cohesive energy as a stability criterion. (author)

  20. Exploring the Therapeutic Affordances of Self-Harm Online Support Communities: An Online Survey of Members

    Science.gov (United States)

    Bullock, Emma

    2017-01-01

    Background A growing number of online communities have been established to support those who self-harm. However, little is known about the therapeutic affordances arising from engagement with these communities and resulting outcomes. Objective The aim of this study was to explore the presence of therapeutic affordances as reported by members of self-harm online support communities. Methods In total, 94 respondents (aged 13-63 years, mean=23.5 years; 94% female) completed an online survey exploring their experiences of engaging with a self-harm online support community. Respondents varied in terms of how long they had been accessing an online community, with 22% (21/94) accessing less than 1 year, 39% (37/94) 1 to 2 years, 14% (13/94) 2 to 3 years, and 24.5% (23/94) more than 3 years. Responses were analyzed using deductive thematic analysis. Results The results of our analysis describe each of the five therapeutic affordances that were present in the data, namely (1) connection, the ability to make contact with others who self-harm for the purposes of mutual support and in so doing reduce feelings of loneliness and isolation; (2) adaptation, that is, how use of online support varies in relation to the personal circumstances of the individual user; (3) exploration, that is, the ability to learn about self-harm and learn about strategies to reduce or stop self-harming behavior; (4) narration, that is, the ability to share experiences, as well as read about the experiences of others; and (5) self-presentation, that is, how and what users present about themselves to others in the online community. Conclusions Our findings suggest that engagement with self-harm online support communities may confer a range of therapeutic benefits for some users, which may serve to minimize the psychosocial burden of self-harm and promote positive coping strategies. In addition, the online nature of the support available may be helpful to those who are unable to access face

  1. Self-Driven Service Learning: Community-Student-Faculty Collaboratives Outside of the Classroom

    Directory of Open Access Journals (Sweden)

    Veronica A. Segarra

    2015-08-01

    Full Text Available Service learning is a community engagement pedagogy often used in the context of the undergraduate classroom to synergize course-learning objectives with community needs.  We find that an effective way to catalyze student engagement in service learning is for student participation to occur outside the context of a graded course, driven by students’ own interests and initiative.  In this paper, we describe the creation and implementation of a self-driven service learning program and discuss its benefits from the community, student, and faculty points of view.  This experience allows students to explore careers in the sciences as well as identify skill strengths and weaknesses in an environment where mentoring is available but where student initiative and self-motivation are the driving forces behind the project’s success.  Self-driven service learning introduces young scientists to the idea that their careers serve a larger community that benefits not only from their discoveries but also from effective communication about how these discoveries are relevant to everyday life.

  2. "Psychological Boarding" and Community-Based Behavioral Health Crisis Stabilization.

    Science.gov (United States)

    Mukherjee, Dhrubodhi; Saxon, Verletta

    2018-01-27

    This exploratory paper presents a case study where a community based mental health organization forging a partnership with a local hospital system to establish a crisis stabilization unit (CSU) to address behavioral health emergency care. The study takes a mixed methods case study approach to address two research questions; (a) did this approach reduce the overall length of stay in the hospital emergency departments? (b) What challenges did the taskforce face in implementing this CSU model? The paper shares recommendation from the findings.

  3. Optimization of self-microemulsifying drug delivery systems (SMEDDS) using a D-optimal design and the desirability function

    DEFF Research Database (Denmark)

    Holm, R.; Jensen, I.H.M.; Sonnergaard, Jørn

    2006-01-01

    with the hard gelatin capsule. Three formulation variables, PEG200, a surfactant mixture, and an oil mixture, were included in the experimental design. The results of the mathematical analysis of the data demonstrated significant interactions among the formulation variables, and the desirability function......D-optimal design and the desirability function were applied to optimize a self-microemulsifying drug delivery system (SMEDDS). The optimized key parameters were the following: 1) particle size of the dispersed emulsion, 2) solubility of the drug in the vehicle, and 3) the vehicle compatibility...

  4. Self-sampling for human papillomavirus in a community setting: feasibility in Hispanic women.

    Science.gov (United States)

    De Alba, Israel; Anton-Culver, Hoda; Hubbell, F Allan; Ziogas, Argyrios; Hess, James R; Bracho, America; Arias, Caleb; Manetta, Alberto

    2008-08-01

    The aim of the study was (a) to assess sensitivity and specificity of self-sampling in a community setting for identifying high-risk human papillomavirus (HPV) infection and abnormal Papanicolaou (Pap) smears and (b) to assess satisfaction with this collection method among Hispanic women. Lay health workers distributed self-collection kits to Hispanic women in the community. Participants collected an unsupervised vaginal sample at home or in the place and time of their preference. A total of 1,213 Hispanics were included and provided a self-sample for HPV testing and were invited for a Pap smear; 662 (55%) of them had a Pap smear and the first 386 of these also had a physician-collected sample for HPV retesting. Using physician collection as the gold standard, unsupervised self-collection had a sensitivity of 90% and specificity of 88% for identifying high-risk HPV. Compared with physician sampling, self-sampling in a community setting had comparable sensitivity for identifying a low-grade lesions or greater in the Pap smear (50% versus 55%; P = 0.45) but lower specificity (94% versus 79%). Overall experience with self-sampling was reported as excellent or very good by 64% and only 2.6% reported a poor or fair experience. Unsupervised self-collection of vaginal samples for HPV testing in a community setting has a high sensitivity for identifying high-risk HPV and a high satisfaction among Hispanics. This approach may benefit populations with limited access to health care or with cultural barriers to cervical cancer screening.

  5. Stabilized transistor transformer for self-moving Sirena-1 X-ray flaw detector

    International Nuclear Information System (INIS)

    Krasil'nikov, S.B.; Kristalinskij, A.L.; Lozovoj, L.N.; Markov, S.N.; Sindalovskij, E.I.

    1986-01-01

    Electric circuit of stabilized transistor transformer for self-moving ''Sirena'' type X-ray flaw detector is described. Specifications of the transformer and results of the experimental studies, which can be used when tuning and adjusting the transformer under industrial conditions

  6. Stability of Ecological Communities and the Architecture of Mutualistic and Trophic Networks

    NARCIS (Netherlands)

    Thebault, E.M.C.; Fontaine, C.

    2010-01-01

    Research on the relationship between the architecture of ecological networks and community stability has mainly focused on one type of interaction at a time, making difficult any comparison between different network types. We used a theoretical approach to show that the network architecture favoring

  7. Pharmaceutical optimization of lipid-based dosage forms for the improvement of taste-masking, chemical stability and solubilizing capacity of phenobarbital.

    Science.gov (United States)

    Monteagudo, Ezequiel; Langenheim, Mariana; Salerno, Claudia; Buontempo, Fabián; Bregni, Carlos; Carlucci, Adriana

    2014-06-01

    Microemulsions (MEs) and self-emulsifying drug delivery systems (SEEDS) containing phenobarbital (Phe) were developed to improve its chemical stability, solubilizing capacity and taste-masking in oral liquid dosage forms. Cremophor® RH40 and Labrasol® were used as surfactants for the screening of ME regions, Capmul® MCM L, Captex® 355, Imwitor® 408, Myglyol® 840 and Isopropyl myristate were the oil phases assayed; Transcutol® P, Polyethylene-glycol 400, glycerol, Propylene-glycol and ethanol the cosurfactants. Phe stability assay was carried out (20:4:20:56% and 20:4:35:41% (w/w); surfactant:oily phase:cosurfactant:water) for both surfactants; only one containing ethanol showed significant dismissing in its drug content. Solubility capacity for these selected formulations were also evaluated, an amount between 17 and 58 mg/mL of Phe could be loaded. At last, an optimized ME formulation with Cremophor® RH40 20%, Capmul® MCM L 4%, PEG 400 35% and sucralose 2% (w/w) was chosen in order to optimize taste-masking using an electronic tongue. Strawberry along with banana and tutti-frutti flavors plus mint flavor proved to be the best ones. Labrasol-based pre-concentrates were tested for (micro)emulsifying properties; all of them resulted to behave as SEDDS. In summary, a rationale experimental design conducted to an optimized ME for Phe oral pediatric administration which was able to load 5-fold times the currently used dose (4 mg/mL), with no sign of physical or chemical instability and with improved taste; SEDDS for capsule filling were also obtained. The biopharmaceutical advantages described for these dosage forms encourage furthering in vivo evaluation.

  8. Plant stimulation of soil microbial community succession: how sequential expression mediates soil carbon stabilization and turnover

    Energy Technology Data Exchange (ETDEWEB)

    Firestone, Mary [Univ. of California, Berkeley, CA (United States)

    2015-03-31

    It is now understood that most plant C is utilized or transformed by soil microorganisms en route to stabilization. Hence the composition of microbial communities that mediate decomposition and transformation of root C is critical, as are the metabolic capabilities of these communities. The change in composition and function of the C-transforming microbial communities over time in effect defines the biological component of soil C stabilization. Our research was designed to test 2 general hypotheses; the first two hypotheses are discussed first; H1: Root-exudate interactions with soil microbial populations results in the expression of enzymatic capacities for macromolecular, complex carbon decomposition; and H2: Microbial communities surrounding roots undergo taxonomic succession linked to functional gene activities as roots grow, mature, and decompose in soil. Over the term of the project we made significant progress in 1) quantifying the temporal pattern of root interactions with the soil decomposing community and 2) characterizing the role of root exudates in mediating these interactions.

  9. Self-adaptive multimethod optimization applied to a tailored heating forging process

    Science.gov (United States)

    Baldan, M.; Steinberg, T.; Baake, E.

    2018-05-01

    The presented paper describes an innovative self-adaptive multi-objective optimization code. Investigation goals concern proving the superiority of this code compared to NGSA-II and applying it to an inductor’s design case study addressed to a “tailored” heating forging application. The choice of the frequency and the heating time are followed by the determination of the turns number and their positions. Finally, a straightforward optimization is performed in order to minimize energy consumption using “optimal control”.

  10. Development of a community's self-efficacy scale for preventing social isolation among community-dwelling older people (Mimamori Scale).

    Science.gov (United States)

    Tadaka, Etsuko; Kono, Ayumi; Ito, Eriko; Kanaya, Yukiko; Dai, Yuka; Imamatsu, Yuki; Itoi, Waka

    2016-11-28

    Among older people in developed countries, social isolation leading to solitary death has become a public health issue of vital importance. Such isolation could be prevented by monitoring at-risk individuals at the neighborhood level and by implementing supportive networks at the community level. However, a means of measuring community confidence in these measures has not been established. This study is aimed at developing the Community's Self-Efficacy Scale (CSES; Mimamori scale in Japanese) for community members preventing social isolation among older people. The CSES is a self-administered questionnaire developed on the basis of Bandura's self-efficacy theory. The survey was given to a general population (GEN) sample (n = 6,000) and community volunteer (CVOL) sample (n = 1,297). Construct validity was determined using confirmatory factor analysis. Internal consistency was calculated using Cronbach's alpha. The Generative Concern Scale (GCS-R) and Brief Sense of Community Scale (BSCS) were also administered to assess criterion-related validity of the CSES. In total, 3,484 and 859 valid responses were received in the GEN and CVOL groups, respectively. The confirmatory factor analysis identified eight items from two domains-community network and neighborhood watch-with goodness of fit index = 0.984, adjusted goodness of fit index = 0.970, comparative fit index = 0.988, and root mean square error of approximation = 0.047. Cronbach's alpha for the entire CSES was 0.87 and for the subscales was 0.80 and higher. The score of the entire CSES was positively correlated with the GCS-R in both the GEN (r = 0.80, p social isolation among older people. The scale is potentially useful for promoting health policies, practices, and interventions within communities. This may help prevent social isolation among older people and contribute to overall well-being in aging societies in Japan and abroad.

  11. Quality of Irrigation Water Affects Soil Functionality and Bacterial Community Stability in Response to Heat Disturbance.

    Science.gov (United States)

    Frenk, Sammy; Hadar, Yitzhak; Minz, Dror

    2018-02-15

    Anthropogenic activities alter the structure and function of a bacterial community. Furthermore, bacterial communities structured by the conditions the anthropogenic activities present may consequently reduce their stability in response to an unpredicted acute disturbance. The present mesocosm-scale study exposed soil bacterial communities to different irrigation water types, including freshwater, fertilized freshwater, treated wastewater, and artificial wastewater, and evaluated their response to a disturbance caused by heat. These effectors may be considered deterministic and stochastic forces common in agricultural operations of arid and semiarid regions. Bacterial communities under conditions of high mineral and organic carbon availability (artificial wastewater) differed from the native bacterial community and showed a proteobacterial dominance. These bacterial communities had a lower resistance to the heat treatment disturbance than soils under conditions of low resource availability (high-quality treated wastewater or freshwater). The latter soil bacterial communities showed a higher abundance of operational taxonomic units (OTUs) classified as Bacilli These results were elucidated by soil under conditions of high resource availability, which lost higher degrees of functional potential and had a greater bacterial community composition change. However, the functional resilience, after the disturbance ended, was higher under a condition of high resource availability despite the bacterial community composition shift and the decrease in species richness. The functional resilience was directly connected to the high growth rates of certain Bacteroidetes and proteobacterial groups. A high stability was found in samples that supported the coexistence of both resistant OTUs and fast-growing OTUs. IMPORTANCE This report presents the results of a study employing a hypothesis-based experimental approach to reveal the forces involved in determining the stability of a

  12. Impacts of stress, self-efficacy, and optimism on suicide ideation among rehabilitation patients with acute pesticide poisoning.

    Science.gov (United States)

    Feng, Jun; Li, Shusheng; Chen, Huawen

    2015-01-01

    The high incidence of pesticide ingestion as a means to commit suicide is a critical public health problem. An important predictor of suicidal behavior is suicide ideation, which is related to stress. However, studies on how to defend against stress-induced suicidal thoughts are limited. This study explores the impact of stress on suicidal ideation by investigating the mediating effect of self-efficacy and dispositional optimism. Direct and indirect (via self-efficacy and dispositional optimism) effects of stress on suicidal ideation were investigated among 296 patients with acute pesticide poisoning from four general hospitals. For this purpose, structural equation modeling (SEM) and bootstrap method were used. Results obtained using SEM and bootstrap method show that stress has a direct effect on suicide ideation. Furthermore, self-efficacy and dispositional optimism partially weakened the relationship between stress and suicidal ideation. The final model shows a significant relationship between stress and suicidal ideation through self-efficacy or dispositional optimism. The findings extended prior studies and provide enlightenment on how self-efficacy and optimism prevents stress-induced suicidal thoughts.

  13. Self-Organizing Networks (SON) Self-Planning, Self-Optimization and Self-Healing for GSM, UMTS and LTE

    CERN Document Server

    Ramiro, Juan

    2011-01-01

    With the current explosion in network traffic, and mounting pressure on operators' business case, Self-Organizing Networks (SON) play a crucial role. They are conceived to minimize human intervention in engineering processes and at the same time improve system performance to maximize Return-on-Investment (ROI) and secure customer loyalty. Written by leading experts in the planning and optimization of Multi-Technology and Multi-Vendor wireless networks, this book describes the architecture of Multi-Technology SON for GSM, UMTS and LTE, along with the enabling technologies for SON planning, opti

  14. Feasibility of self-correcting quantum memory and thermal stability of topological order

    International Nuclear Information System (INIS)

    Yoshida, Beni

    2011-01-01

    Recently, it has become apparent that the thermal stability of topologically ordered systems at finite temperature, as discussed in condensed matter physics, can be studied by addressing the feasibility of self-correcting quantum memory, as discussed in quantum information science. Here, with this correspondence in mind, we propose a model of quantum codes that may cover a large class of physically realizable quantum memory. The model is supported by a certain class of gapped spin Hamiltonians, called stabilizer Hamiltonians, with translation symmetries and a small number of ground states that does not grow with the system size. We show that the model does not work as self-correcting quantum memory due to a certain topological constraint on geometric shapes of its logical operators. This quantum coding theoretical result implies that systems covered or approximated by the model cannot have thermally stable topological order, meaning that systems cannot be stable against both thermal fluctuations and local perturbations simultaneously in two and three spatial dimensions. - Highlights: → We define a class of physically realizable quantum codes. → We determine their coding and physical properties completely. → We establish the connection between topological order and self-correcting memory. → We find they do not work as self-correcting quantum memory. → We find they do not have thermally stable topological order.

  15. Persistence at an Urban Community College: The Implications of Self-Efficacy and Motivation

    Science.gov (United States)

    Liao, Hsiang-Ann; Edlin, Margot; Ferdenzi, Anita Cuttita

    2014-01-01

    This study examined how self-efficacy and motivation affected student persistence at an urban community college. Self-efficacy was studied at two dimensions: self-regulated learning efficacy and self-efficacy for academic achievement. Motivation was also investigated at two levels: intrinsic motivation and extrinsic motivation. Results show that…

  16. Optimality and self-organization in river deltas

    Science.gov (United States)

    Tejedor, A.; Longjas, A.; Edmonds, D. A.; Zaliapin, I. V.; Georgiou, T. T.; Rinaldo, A.; Foufoula-Georgiou, E.

    2017-12-01

    Deltas are nourished by channel networks, whose connectivity constrains, if not drives, the evolution, functionality and resilience of these systems. Understanding the coevolution of deltaic channels and their flux organization is crucial for guiding maintenance strategies of these highly stressed systems from a range of anthropogenic activities. However, in contrast to tributary channel networks, to date, no theory has been proposed to explain how deltas self-organize to distribute water and sediment to the delta top and the shoreline. Here, we hypothesize the existence of an optimality principle underlying the self-organized partition of fluxes in delta channel networks. Specifically, we hypothesize that deltas distribute water and sediment fluxes on a given delta topology such as to maximize the diversity of flux delivery to the shoreline. By introducing the concept of nonlocal Entropy Rate (nER) and analyzing ten field deltas in diverse environments, we present evidence that supports our hypothesis, suggesting that delta networks achieve dynamically accessible maxima of their nER. Furthermore, by analyzing six simulated deltas using the Delf3D model and following their topologic and flux re-organization before and after major avulsions, we further study the evolution of nER and confirm our hypothesis. We discuss how optimal flux distributions in terms of nER, when interpreted in terms of resilience, are configurations that reflect an increased ability to withstand perturbations.

  17. Axial ratio dependence of the stability of self-interstitials in HCP structures

    International Nuclear Information System (INIS)

    Peng, Qing; Ji, Wei; Huang, Hanchen; De, Suvranu

    2013-01-01

    We investigate the effect of the axial ratio (c/a) on the stability of self-interstitial atoms (SIAs) in hexagonal close-packed crystal structures, using hcp-zirconium as a prototype, through density functional theory based ab initio calculations. The axial ratio is found to dominate the relative stability of SIAs over volumetric strains. We observe that below the ideal value of 1.633, the basal octahedral configuration is the most stable. Above the ideal value, the off-plane SIAs are more stable than in-plane ones

  18. The role of self-efficacy, self-esteem and optimism for using routine health check-ups in a population-based sample. A longitudinal perspective.

    Science.gov (United States)

    Hajek, André; Hans-Helmut-König

    2017-12-01

    While several cross-sectional studies have shown that self-efficacy, self-esteem and optimism are associated with the use of routine health check-ups, little is known about this relationship based on longitudinal studies. Consequently, the purpose of this study was to examine whether these factors are associated with routine health check-ups longitudinally. Data were retrieved from a population-based longitudinal study of individuals (≥40years of age) residing in private households in Germany (two waves: 2008 and 2011). Widely established scales were used to quantify self-efficacy, self-esteem, and optimism. Respondents reported whether they used a health check-up in the last two years. Conditional fixed-effects logistic regressions were used (n=1504), adjusting for socio-demographic, lifestyle and health-related variables. After adjusting for various potential confounders, regression analysis revealed that the use of routine health check-ups increased with self-efficacy [OR: 1.71 (95%-CI: 1.14-2.55)], self-esteem [OR: 1.78 (1.16-2.73)], and optimism [OR: 1.37 (1.01-1.86)]. Furthermore, the use of routine health check-ups increased with changes from employment to retirement [OR: 2.60 (1.34-5.03)], whereas it was not associated with changes in age, marital status, smoking status, the number of physical illnesses, self-rated health and body-mass index. The current study stresses the importance of an association between screening behavior and self-efficacy, self-esteem and optimism longitudinally. Interventions aiming at modifying these psychological factors might help to increase the use of routine health check-ups. Copyright © 2017 Elsevier Inc. All rights reserved.

  19. A Self-Stabilizing Synchronization Protocol for Arbitrary Digraphs

    Science.gov (United States)

    Malekpour, Mahyar R.

    2011-01-01

    This paper presents a self-stabilizing distributed clock synchronization protocol in the absence of faults in the system. It is focused on the distributed clock synchronization of an arbitrary, non-partitioned digraph ranging from fully connected to 1-connected networks of nodes while allowing for differences in the network elements. This protocol does not rely on assumptions about the initial state of the system, other than the presence of at least one node, and no central clock or a centrally generated signal, pulse, or message is used. Nodes are anonymous, i.e., they do not have unique identities. There is no theoretical limit on the maximum number of participating nodes. The only constraint on the behavior of the node is that the interactions with other nodes are restricted to defined links and interfaces. This protocol deterministically converges within a time bound that is a linear function of the self-stabilization period. We present an outline of a deductive proof of the correctness of the protocol. A bounded model of the protocol was mechanically verified for a variety of topologies. Results of the mechanical proof of the correctness of the protocol are provided. The model checking results have verified the correctness of the protocol as they apply to the networks with unidirectional and bidirectional links. In addition, the results confirm the claims of determinism and linear convergence. As a result, we conjecture that the protocol solves the general case of this problem. We also present several variations of the protocol and discuss that this synchronization protocol is indeed an emergent system.

  20. Model Checking a Self-Stabilizing Distributed Clock Synchronization Protocol for Arbitrary Digraphs

    Science.gov (United States)

    Malekpour, Mahyar R.

    2011-01-01

    This report presents the mechanical verification of a self-stabilizing distributed clock synchronization protocol for arbitrary digraphs in the absence of faults. This protocol does not rely on assumptions about the initial state of the system, other than the presence of at least one node, and no central clock or a centrally generated signal, pulse, or message is used. The system under study is an arbitrary, non-partitioned digraph ranging from fully connected to 1-connected networks of nodes while allowing for differences in the network elements. Nodes are anonymous, i.e., they do not have unique identities. There is no theoretical limit on the maximum number of participating nodes. The only constraint on the behavior of the node is that the interactions with other nodes are restricted to defined links and interfaces. This protocol deterministically converges within a time bound that is a linear function of the self-stabilization period.

  1. Formative Self-Assessment College Classes Improves Self-Regulation and Retention in First/Second Year Community College Students

    Science.gov (United States)

    Mahlberg, Jamie

    2015-01-01

    This research examined the influence formative self-assessment had on first/second year community college student self-regulatory practices. Previous research has shown that the ability to regulate one's learning activities can improve performance in college classes, and it has long been known that the use of formative assessment improves…

  2. Relationships among optimism, well-being, self-transcendence, coping, and social support in women during treatment for breast cancer.

    Science.gov (United States)

    Matthews, Ellyn E; Cook, Paul F

    2009-07-01

    The impact of diagnosis and treatment for breast cancer, stressors that affect emotional well-being, is influenced by several psychosocial factors and the relationships among them. The purpose of this study was to investigate the relationship between optimism and emotional well-being (EWB) and the individual and combined mediation of this relationship by perceived social support (SS), problem focused coping (PFC), and self-transcendence in women with breast cancer during radiation therapy. Ninety-three women receiving radiation treatment for breast cancer completed questionnaires that measured EWB, optimism, SS, PFC, and self-transcendence. Correlational and multiple regression analysis revealed that optimism was positively related to EWB. Of the three mediators, self-transcendence alone was found to partially mediate the relationship between optimism and EWB. The relationship between optimism and PFC was not significant. Optimism was related to SS, but its indirect effect on EWB through SS did not reach significance. During breast cancer treatment, the positive effects of optimism on EWB are partially mediated by a woman's level of self-transcendence. Brief screening of women's optimism may help identify women at risk for psychological distress. Early detection and interventions to promote psychological adjustment throughout the cancer trajectory (e.g. enhancing self-transcendence) should receive attention in future research. (c) 2008 John Wiley & Sons, Ltd.

  3. Self-care practices of Malaysian adults with diabetes and sub-optimal glycaemic control.

    Science.gov (United States)

    Tan, Ming Yeong; Magarey, Judy

    2008-08-01

    To investigate the self-care practices of Malaysian adults with diabetes and sub-optimal glycaemic control. Using a one-to-one interviewing approach, data were collected from 126 diabetic adults from four settings. A 75-item questionnaire was used to assess diabetes-related knowledge and self-care practices regarding, diet, medication, physical activity and self-monitoring of blood glucose (SMBG). Most subjects had received advice on the importance of self-care in the management of their diabetes and recognised its importance. Sixty-seven subjects (53%) scored below 50% in their diabetes-related knowledge. Subjects who consumed more meals per day (80%), or who did not include their regular sweetened food intakes in their daily meal plan (80%), or who were inactive in daily life (54%), had higher mean fasting blood glucose levels (p=0.04). Subjects with medication non-adherence (46%) also tended to have higher fasting blood glucose levels. Only 15% of the subjects practiced SMBG. Predictors of knowledge deficit and poor self-care were low level of education (p = <0.01), older subjects (p=0.04) and Type 2 diabetes subjects on oral anti-hyperglycaemic medication (p = <0.01). There were diabetes-related knowledge deficits and inadequate self-care practices among the majority of diabetic patients with sub-optimal glycaemic control. This study should contribute to the development of effective education strategies to promote health for adults with sub-optimal diabetes control.

  4. LISA Pathfinder E2E performance simulation: optical and self-gravity stability analysis

    Science.gov (United States)

    Brandt, N.; Fichter, W.; Kersten, M.; Lucarelli, S.; Montemurro, F.

    2005-05-01

    End-to-end (E2E) modelling and simulation, i.e. verifying the science performance of LISA Pathfinder (spacecraft and payload), is mandatory in order to minimize mission risks. In this paper, focus is on two particular applications of the E2E performance simulator currently being developed at EADS Astrium GmbH: the opto-dynamical stability and the self-gravity disturbance stability analysis. The E2E models applied here comprise the opto-dynamical modelling of the optical metrology systems (OMS) laser interferometry, the thermo-elastic distortion modelling of the OMS optical elements and the self-gravity disturbance model accounting for structural distortions. Preliminary analysis results are presented in detail, identifying shortcomings of the current LISA technology package (LTP) mounting baseline. As a consequence, the design is now being revised.

  5. LISA Pathfinder E2E performance simulation: optical and self-gravity stability analysis

    International Nuclear Information System (INIS)

    Brandt, N; Fichter, W; Kersten, M; Lucarelli, S; Montemurro, F

    2005-01-01

    End-to-end (E2E) modelling and simulation, i.e. verifying the science performance of LISA Pathfinder (spacecraft and payload), is mandatory in order to minimize mission risks. In this paper, focus is on two particular applications of the E2E performance simulator currently being developed at EADS Astrium GmbH: the opto-dynamical stability and the self-gravity disturbance stability analysis. The E2E models applied here comprise the opto-dynamical modelling of the optical metrology systems (OMS) laser interferometry, the thermo-elastic distortion modelling of the OMS optical elements and the self-gravity disturbance model accounting for structural distortions. Preliminary analysis results are presented in detail, identifying shortcomings of the current LISA technology package (LTP) mounting baseline. As a consequence, the design is now being revised

  6. Expression, stabilization and purification of membrane proteins via diverse protein synthesis systems and detergents involving cell-free associated with self-assembly peptide surfactants.

    Science.gov (United States)

    Zheng, Xuan; Dong, Shuangshuang; Zheng, Jie; Li, Duanhua; Li, Feng; Luo, Zhongli

    2014-01-01

    G-protein coupled receptors (GPCRs) are involved in regulating most of physiological actions and metabolism in the bodies, which have become most frequently addressed therapeutic targets for various disorders and diseases. Purified GPCR-based drug discoveries have become routine that approaches to structural study, novel biophysical and biochemical function analyses. However, several bottlenecks that GPCR-directed drugs need to conquer the problems including overexpression, solubilization, and purification as well as stabilization. The breakthroughs are to obtain efficient protein yield and stabilize their functional conformation which are both urgently requiring of effective protein synthesis system methods and optimal surfactants. Cell-free protein synthesis system is superior to the high yields and post-translation modifications, and early signs of self-assembly peptide detergents also emerged to superiority in purification of membrane proteins. We herein focus several predominant protein synthesis systems and surfactants involving the novel peptide detergents, and uncover the advantages of cell-free protein synthesis system with self-assembling peptide detergents in purification of functional GPCRs. This review is useful to further study in membrane proteins as well as the new drug exploration. Copyright © 2014 Elsevier Inc. All rights reserved.

  7. Political stability in conditions of overtaking modernisation: challenges and reference points

    Directory of Open Access Journals (Sweden)

    M. K. Mantashyan

    2017-07-01

    To sum up, compensatory mechanisms of the political stability in conditions of the ongoing modernization should accelerate the development of civil society within the absence of a stable and adaptive political community. Challenges to political stability should be compensated by creativity and optimality of the authorities’ activities. Prospects for further consideration of problems, being raised in this paper, are as following: to determine the socio-cultural constraints of the institutional adaptability of the political system.

  8. Machine assisted reaction optimization: A self-optimizing reactor system for continuous-flow photochemical reactions

    KAUST Repository

    Poscharny, K.; Fabry, D.C.; Heddrich, S.; Sugiono, E.; Liauw, M.A.; Rueping, Magnus

    2018-01-01

    A methodology for the synthesis of oxetanes from benzophenone and furan derivatives is presented. UV-light irradiation in batch and flow systems allowed the [2 + 2] cycloaddition reaction to proceed and a broad range of oxetanes could be synthesized in manual and automated fashion. The identification of high-yielding reaction parameters was achieved through a new self-optimizing photoreactor system.

  9. Machine assisted reaction optimization: A self-optimizing reactor system for continuous-flow photochemical reactions

    KAUST Repository

    Poscharny, K.

    2018-04-07

    A methodology for the synthesis of oxetanes from benzophenone and furan derivatives is presented. UV-light irradiation in batch and flow systems allowed the [2 + 2] cycloaddition reaction to proceed and a broad range of oxetanes could be synthesized in manual and automated fashion. The identification of high-yielding reaction parameters was achieved through a new self-optimizing photoreactor system.

  10. Exploring the Therapeutic Affordances of Self-Harm Online Support Communities: An Online Survey of Members.

    Science.gov (United States)

    Coulson, Neil S; Bullock, Emma; Rodham, Karen

    2017-10-13

    A growing number of online communities have been established to support those who self-harm. However, little is known about the therapeutic affordances arising from engagement with these communities and resulting outcomes. The aim of this study was to explore the presence of therapeutic affordances as reported by members of self-harm online support communities. In total, 94 respondents (aged 13-63 years, mean=23.5 years; 94% female) completed an online survey exploring their experiences of engaging with a self-harm online support community. Respondents varied in terms of how long they had been accessing an online community, with 22% (21/94) accessing less than 1 year, 39% (37/94) 1 to 2 years, 14% (13/94) 2 to 3 years, and 24.5% (23/94) more than 3 years. Responses were analyzed using deductive thematic analysis. The results of our analysis describe each of the five therapeutic affordances that were present in the data, namely (1) connection, the ability to make contact with others who self-harm for the purposes of mutual support and in so doing reduce feelings of loneliness and isolation; (2) adaptation, that is, how use of online support varies in relation to the personal circumstances of the individual user; (3) exploration, that is, the ability to learn about self-harm and learn about strategies to reduce or stop self-harming behavior; (4) narration, that is, the ability to share experiences, as well as read about the experiences of others; and (5) self-presentation, that is, how and what users present about themselves to others in the online community. Our findings suggest that engagement with self-harm online support communities may confer a range of therapeutic benefits for some users, which may serve to minimize the psychosocial burden of self-harm and promote positive coping strategies. In addition, the online nature of the support available may be helpful to those who are unable to access face-to-face support. ©Neil S Coulson, Emma Bullock, Karen Rodham

  11. Mean-variance portfolio analysis data for optimizing community-based photovoltaic investment.

    Science.gov (United States)

    Shakouri, Mahmoud; Lee, Hyun Woo

    2016-03-01

    The amount of electricity generated by Photovoltaic (PV) systems is affected by factors such as shading, building orientation and roof slope. To increase electricity generation and reduce volatility in generation of PV systems, a portfolio of PV systems can be made which takes advantages of the potential synergy among neighboring buildings. This paper contains data supporting the research article entitled: PACPIM: new decision-support model of optimized portfolio analysis for community-based photovoltaic investment [1]. We present a set of data relating to physical properties of 24 houses in Oregon, USA, along with simulated hourly electricity data for the installed PV systems. The developed Matlab code to construct optimized portfolios is also provided in . The application of these files can be generalized to variety of communities interested in investing on PV systems.

  12. Evaluating Stability and Comparing Output of Feature Selectors that Optimize Feature Subset Cardinality

    Czech Academy of Sciences Publication Activity Database

    Somol, Petr; Novovičová, Jana

    2010-01-01

    Roč. 32, č. 11 (2010), s. 1921-1939 ISSN 0162-8828 R&D Projects: GA MŠk 1M0572; GA ČR GA102/08/0593; GA ČR GA102/07/1594 Grant - others:GA MŠk(CZ) 2C06019 Institutional research plan: CEZ:AV0Z10750506 Keywords : feature selection * feature stability * stability measures * similarity measures * sequential search * individual ranking * feature subset-size optimization * high dimensionality * small sample size Subject RIV: BD - Theory of Information Impact factor: 5.027, year: 2010 http://library.utia.cas.cz/separaty/2010/RO/somol-0348726.pdf

  13. Perceptions of community, social capital, and how they affect self-reported health: a multilevel analysis.

    Science.gov (United States)

    Dziadkowiec, O; Meissen, G J; Merkle, E C

    2017-11-01

    The link between social capital and self-reported health has been widely explored. On the other hand, we know less about the relationship between social capital, community socioeconomic characteristics, and non-social capital-related individual differences, and about their impact on self-reported health in community settings. Cross-sectional study design with a proportional sample of 7965 individuals from 20 US communities were analyzed using multilevel linear regression models, where individuals were nested within communities. The response rates ranged from 13.5% to 25.4%. Findings suggest that perceptions of the community and individual level socioeconomic characteristics were stronger predictors of self-reported health than were social capital or community socioeconomic characteristics. Policy initiatives aimed at increasing social capital should first assess community member's perceptions of their communities to uncover potential assets to help increase social capital. Copyright © 2017 The Royal Society for Public Health. Published by Elsevier Ltd. All rights reserved.

  14. Application of simplex-centroid mixture design to optimize stabilizer combinations for ice cream manufacture.

    Science.gov (United States)

    BahramParvar, Maryam; Tehrani, Mostafa Mazaheri; Razavi, Seyed M A; Koocheki, Arash

    2015-03-01

    This study aimed to obtain the optimum formulation for stabilizers in ice cream that could contest with blends presented nowadays. Thus, different mixtures of three stabilizers, i.e. basil seed gum, carboxymethyl cellulose, and guar gum, at two concentrations (0.15 % & 0.35 %) were studied using mixture design methodology. The influence of these mixtures on some properties of ice cream and the regression models for them were also determined. Generally, high ratios of basil seed gum in mixture developed the apparent viscosity of ice cream mixes and decreased the melting rate. Increasing proportion of this stabilizer as well as guar gum in the mixtures at concentration of 0.15 % enhanced the overrun of samples. Based on the optimization criteria, the most excellent combination was 84.43 % basil seed gum and 15.57 % guar gum at concentration of 0.15 %. This research proved the capability of basil seed gum as a novel stabilizer in ice cream stabilization.

  15. Design and experimental investigation of a decentralized GA-optimized neuro-fuzzy power system stabilizer

    Energy Technology Data Exchange (ETDEWEB)

    Talaat, Hossam E.A.; Abdennour, Adel; Al-Sulaiman, Abdulaziz A. [Electrical Engineering Department, College of Engineering, King Saud University, P.O. Box 800, Riyadh 11421 (Saudi Arabia)

    2010-09-15

    The aim of this research is the design and implementation of a decentralized power system stabilizer (PSS) capable of performing well for a wide range of variations in system parameters and/or loading conditions. The framework of the design is based on Fuzzy Logic Control (FLC). In particular, the neuro-fuzzy control rules are derived from training three classical PSSs; each is tuned using GA so as to perform optimally at one operating point. The effectiveness and robustness of the designed stabilizer, after implementing it to the laboratory model, is investigated. The results of real-time implementation prove that the proposed PSS offers a superior performance in comparison with the conventional stabilizer. (author)

  16. Self-Referential Processing in Adolescents: Stability of Behavioral and Event-Related Potential Markers

    Science.gov (United States)

    Auerbach, Randy P.; Bondy, Erin; Stanton, Colin H.; Webb, Christian A.; Shankman, Stewart A.; Pizzagalli, Diego A.

    2016-01-01

    The self-referential encoding task (SRET)—an implicit measure of self-schema—has been used widely to probe cognitive biases associated with depression, including among adolescents. However, research testing the stability of behavioral and electrocortical effects is sparse. Therefore, the current study sought to evaluate the stability of behavioral markers and event-related potentials (ERP) elicited from the SRET over time in healthy, female adolescents (n = 31). At baseline, participants were administered a diagnostic interview and a self-report measure of depression severity. In addition, they completed the SRET while 128-channel event-related potential (ERP) data were recorded to examine early (P1) and late (late positive potential [LPP]) ERPs. Three months later, participants were re-administered the depression self-report measure and the SRET in conjunction with ERPs. Results revealed that healthy adolescents endorsed, recalled, and recognized more positive and fewer negative words at each assessment, and these effects were stable over time (rs = 0.44–0.83). Similarly, they reported a faster reaction time when endorsing self-relevant positive words, as opposed to negative words, at both the initial and follow-up assessment (r = 0.82). Second, ERP responses, specifically potentiated P1 and late LPP positivity to positive versus negative words, were consistent over time (rs = 0.56–0.83), and the internal reliability of ERPs were robust at each time point (rs = 0.52–0.80). As a whole, these medium-to-large effects suggest that the SRET is a reliable behavioral and neural probe of self-referential processing. PMID:27302282

  17. Think Positively and Feel Positively: Optimism and Life Satisfaction in Late Life

    Science.gov (United States)

    Leung, Beeto Wai-Chung; Moneta, Giovanni B.; Mcbride-Chang, Catherine

    2005-01-01

    This study developed a dispositional path model of life satisfaction for community dwelling Chinese elderly living in Hong Kong. A sample of 117 elderly completed scales measuring life satisfaction, optimism, self-esteem, relationship harmony, self-construals, and perceived/expected health and financial status. Modeling revealed that life…

  18. Development of emotional stability scale

    Directory of Open Access Journals (Sweden)

    M Chaturvedi

    2010-01-01

    Full Text Available Background: Emotional stability remains the central theme in personality studies. The concept of stable emotional behavior at any level is that which reflects the fruits of normal emotional development. The study aims at development of an emotional stability scale. Materials and Methods: Based on available literature the components of emotional stability were identified and 250 items were developed, covering each component. Two-stage elimination of items was carried out, i.e. through judges′ opinions and item analysis. Results: Fifty items with highest ′t′ values covering 5 dimensions of emotional stability viz pessimism vs. optimism, anxiety vs. calm, aggression vs. tolerance., dependence vs. autonomy., apathy vs. empathy were retained in the final scale. Reliability as checked by Cronbach′s alpha was .81 and by split half method it was .79. Content validity and construct validity were checked. Norms are given in the form of cumulative percentages. Conclusion: Based on the psychometric principles a 50 item, self-administered 5 point Lickert type rating scale was developed for measurement of emotional stability.

  19. Stability of Self-Reported Arousal to Sexual Fantasies Involving Children in a Clinical Sample of Pedophiles and Hebephiles.

    Science.gov (United States)

    Grundmann, Dorit; Krupp, Jurian; Scherner, Gerold; Amelung, Till; Beier, Klaus M

    2016-07-01

    In forensic research, there is a controversial discussion concerning the changeability or stability of pedophilia. Seto (2012) conceptualized pedophilia as a sexual age orientation characterized by an early onset, correlations with sexual and romantic behavior, and stability over time. However, empirical data are sparse and are mostly based on samples of detected offenders. The present study examined self-reported arousal to sexual fantasies involving children in a clinical sample of pedo-/hebephiles. In Study 1, retrospective self-reports on the age of onset and duration of sexual interest in minors were examined. In Study 2, the stability and variability of self-reported arousal to sexual fantasies involving children were evaluated prospectively. Non-prosecuted self-identifying pedo-/hebephilic men seeking professional help were recruited within the Berlin Prevention Project Dunkelfeld. Between 2005 and 2013, 494 participants completed the intake assessment. Self-reported data were collected via questionnaire focusing on sexual arousal to fantasies during masturbation involving prepubescent and/or early pubescent minors. Subsequent assessments of sexual arousal were obtained for 121 of the participants. The average time between the first and last assessment was approximately 29 months. Spearman's correlation coefficients examined the between-group rank-order and Wilcoxon signed-rank tests examined the within-individual mean-level stability. The majority of subjects reported an early onset of their pedo-/hebephilic sexual arousal. The rank-order stability was medium to high. Over the investigated period, the majority of subjects showed no or only minimal decrease or increase of self-reported sexual arousal. These results suggested that sexual arousal to fantasies involving prepubescent and/or early pubescent children is stable. Furthermore, the results support the conceptualization of pedo-/hebephilia as a sexual age orientation in men.

  20. Affective profiles in Italian high school students: life satisfaction, psychological well-being, self-esteem, and optimism.

    Science.gov (United States)

    Di Fabio, Annamaria; Bucci, Ornella

    2015-01-01

    The affective profiles model distinguishes between individuals who are self-fulfilling (high positive affect, low negative affect), high affective (high positive affect, high negative affect), low affective (low positive affect, low negative affect), and self-destructive (low positive affect, high negative affect). The literature shows that the affective profiles model has been used with Swedish people in particular in order to determine differences among profiles in relation to life satisfaction, psychological well-being, self-esteem, and optimism. The present research investigated these differences in Italian high school students. Two studies were conducted: the first with 156 Italian high school students and the second with 148 Italian high school students. The first study analyzed differences among affective profiles with regard to life satisfaction and psychological well-being while the second study analyzed differences among affective profiles with regard to self-esteem and optimism. In the first study, the Positive and Negative Affect Schedule (PANAS), the Satisfaction with Life Scale, and the Meaningful Life Measure were administered to the participants. In the second study, the PANAS, the Self-Esteem Scale, the Life Orientation Test-revised were administered to the participants. The results of the first study showed that, with respect to the other profiles, the self-fulfilling participants had greater life satisfaction and psychological well-being. The results of the second study showed that, with respect to the other profiles, the self-fulfilling participants had higher self-esteem and optimism. These results revealed differences among affective profiles regarding life satisfaction, psychological well-being, self-esteem, and optimism in the Italian context as well thereby offering new possibilities for cross-cultural research and for enhancing self-fulfilling profiles.

  1. The environmental self-management in the university community

    Directory of Open Access Journals (Sweden)

    Rogelio García-Tejera

    2016-09-01

    Full Text Available The System of Education Cuban power to the school like center promoter of the development, their social projection includes the satisfaction of the educational necessities of the community. The community environmental education for the sustainable development is inserted in the educational administration of the school like cultural center. To consider the university space as a community, he/she gives the possibility to carry out actions of self-management with the objective of improving the atmosphere in the university community, when the experiences that characterize to the cultural practices of the university students taking advantage. For the non formal road, it is contributed to the environmental formation, when stimulating the responsibility for the planning and execution of the methods that characterize the administration of their atmosphere, to make emphasis in the critic to the not wanted behaviors, to promote the voluntary commitment of the active participation of each one of their members and to achieve the work of the juvenile organizations.

  2. Self-reported sexual assault in convicted sex offenders and community men.

    Science.gov (United States)

    Widman, Laura; Olson, Michael A; Bolen, Rebecca M

    2013-05-01

    Although self-reported sexual assault perpetrated by men against women has been well documented among college men, less is known about self-reported perpetration among convicted sex offenders and community men. This study provides unique descriptive and comparative information on sexual assaults in these understudied populations. Participants were 40 convicted sex offenders and 49 demographically comparable community men who completed the Sexual Experiences Survey (SES; Abbey, Parkhill, & Koss, 2005; Koss, Gidycz, & Wisniewski, 1987) and other surveys to capture the promiscuous sex and hostile masculinity pathways posited by the confluence model (Malamuth, 2003). We found notably few differences between sex offenders and community men in the rate and severity of sexual assault perpetration and the tactics used to obtain unwanted sexual contact. Specifically, 68% of sex offenders and 59% of community men acknowledged they had perpetrated sexual assault. Both groups used guilt and anger as the most frequent tactics to obtain unwanted sexual activity from their female victims. Consistent with the confluence model, an impersonal orientation toward sexual relationships was associated with sexual assault for both sex offenders and community men. Future directions for research on sexual assault perpetration and violence prevention efforts are discussed in light of these findings.

  3. Bacterial Quorum Sensing Stabilizes Cooperation by Optimizing Growth Strategies.

    Science.gov (United States)

    Bruger, Eric L; Waters, Christopher M

    2016-11-15

    Communication has been suggested as a mechanism to stabilize cooperation. In bacteria, chemical communication, termed quorum sensing (QS), has been hypothesized to fill this role, and extracellular public goods are often induced by QS at high cell densities. Here we show, with the bacterium Vibrio harveyi, that QS provides strong resistance against invasion of a QS defector strain by maximizing the cellular growth rate at low cell densities while achieving maximum productivity through protease upregulation at high cell densities. In contrast, QS mutants that act as defectors or unconditional cooperators maximize either the growth rate or the growth yield, respectively, and thus are less fit than the wild-type QS strain. Our findings provide experimental evidence that regulation mediated by microbial communication can optimize growth strategies and stabilize cooperative phenotypes by preventing defector invasion, even under well-mixed conditions. This effect is due to a combination of responsiveness to environmental conditions provided by QS, lowering of competitive costs when QS is not induced, and pleiotropic constraints imposed on defectors that do not perform QS. Cooperation is a fundamental problem for evolutionary biology to explain. Conditional participation through phenotypic plasticity driven by communication is a potential solution to this dilemma. Thus, among bacteria, QS has been proposed to be a proximate stabilizing mechanism for cooperative behaviors. Here, we empirically demonstrate that QS in V. harveyi prevents cheating and subsequent invasion by nonproducing defectors by maximizing the growth rate at low cell densities and the growth yield at high cell densities, whereas an unconditional cooperator is rapidly driven to extinction by defectors. Our findings provide experimental evidence that QS regulation prevents the invasion of cooperative populations by QS defectors even under unstructured conditions, and they strongly support the role of

  4. Self-optimizing approach for automated laser resonator alignment

    Science.gov (United States)

    Brecher, C.; Schmitt, R.; Loosen, P.; Guerrero, V.; Pyschny, N.; Pavim, A.; Gatej, A.

    2012-02-01

    Nowadays, the assembly of laser systems is dominated by manual operations, involving elaborate alignment by means of adjustable mountings. From a competition perspective, the most challenging problem in laser source manufacturing is price pressure, a result of cost competition exerted mainly from Asia. From an economical point of view, an automated assembly of laser systems defines a better approach to produce more reliable units at lower cost. However, the step from today's manual solutions towards an automated assembly requires parallel developments regarding product design, automation equipment and assembly processes. This paper introduces briefly the idea of self-optimizing technical systems as a new approach towards highly flexible automation. Technically, the work focuses on the precision assembly of laser resonators, which is one of the final and most crucial assembly steps in terms of beam quality and laser power. The paper presents a new design approach for miniaturized laser systems and new automation concepts for a robot-based precision assembly, as well as passive and active alignment methods, which are based on a self-optimizing approach. Very promising results have already been achieved, considerably reducing the duration and complexity of the laser resonator assembly. These results as well as future development perspectives are discussed.

  5. A Study of the Lateral Stability of Self-Propelled Fruit Harvesters

    Directory of Open Access Journals (Sweden)

    Maurizio Cutini

    2017-11-01

    Full Text Available Self-propelled fruit harvesters (SPFHs are agricultural machines designed to facilitate fruit picking and other tasks requiring operators to stay close to the foliage or to the upper part of the canopy. They generally consist of a chassis with a variable height working platform that can be equipped with lateral extending platforms. The positioning of additional masses (operators, fruit bins and the maximum height of the platform (up to three meters above the ground strongly affect machine stability. Since there are no specific studies on the lateral stability of SPFHs, this study aimed to develop a specific test procedure to fill this gap. A survey of the Italian market found 20 firms manufacturing 110 different models of vehicles. Observation and monitoring of SPFHs under real operational conditions revealed the variables mostly likely to affect lateral stability: the position and mass of the operators and the fruit bin on the platform. Two SPFHs were tested in the laboratory to determine their centre of gravity and lateral stability in four different settings reproducing operational conditions. The test setting was found to affect the stability angle. Lastly, the study identified two specific settings reproducing real operational conditions most likely to affect the lateral stability of SPFHs: these should be used as standard, reproducible settings to enable a comparison of results.

  6. Stability and change of personality traits, self-esteem, and well-being: Introducing the meta-analytic stability and change model of retest correlations.

    Science.gov (United States)

    Anusic, Ivana; Schimmack, Ulrich

    2016-05-01

    The stability of individual differences is a fundamental issue in personality psychology. Although accumulating evidence suggests that many psychological attributes are both stable and change over time, existing research rarely takes advantage of theoretical models that capture both stability and change. In this article, we present the Meta-Analytic Stability and Change model (MASC), a novel meta-analytic model for synthesizing data from longitudinal studies. MASC is based on trait-state models that can separate influences of stable and changing factors from unreliable variance (Kenny & Zautra, 1995). We used MASC to evaluate the extent to which personality traits, life satisfaction, affect, and self-esteem are influenced by these different factors. The results showed that the majority of reliable variance in personality traits is attributable to stable influences (83%). Changing factors had a greater influence on reliable variance in life satisfaction, self-esteem, and affect than in personality (42%-56% vs. 17%). In addition, changing influences on well-being were more stable than changing influences on personality traits, suggesting that different changing factors contribute to personality and well-being. Measures of affect were less reliable than measures of the other 3 constructs, reflecting influences of transient factors, such as mood on affective judgments. After accounting for differences in reliability, stability of affect did not differ from other well-being variables. Consistent with previous research, we found that stability of individual differences increases with age. (PsycINFO Database Record (c) 2016 APA, all rights reserved).

  7. Towards a Knowledge Building Community: From Guided to Self-Organized Inquiry

    Directory of Open Access Journals (Sweden)

    Stefano Cacciamani

    2010-11-01

    Full Text Available Over four academic years a design experiment was conducted involving four online university courses with the goal of shifting from Guided to Self-Organized Inquiry to foster Knowledge Building communities in the classroom. Quantitative analyses focused on notes contributed to collective knowledge spaces, as well as reading and building-on notes of others. All team members, including teachers, contributed at high levels. Students tended to produce more notes in the guided-inquiry approach but read more and demonstrated more even distribution of work as part of self-organized inquiry. Qualitative data focused on strategies students reported as new to their school experience. Strategies fell into three categories common to both guided and self-organizing inquiry: elaborating course content for depth of understanding, collaboration in an online environment, and metacognition, with greater reflection on idea development. Distinctive aspects of self-organized inquiry, according to student reports, included going beyond given information, linking new understandings and personal experiences, attention to the collective works of the community, and learning from instructor’s strategies.

  8. The effectiveness of beauty care on self-rated health among community-dwelling older people.

    Science.gov (United States)

    Kawai, Hisashi; Inomata, Takashi; Otsuka, Rika; Sugiyama, Yoichi; Hirano, Hirohiko; Obuchi, Shuichi

    2016-01-01

    The maintenance and improvement of self-rated health is important for prolonging healthy life expectancy in a well-aged society. In the present study, we examined the effectiveness of beauty care on self-rated health among community-dwelling older people through a quasi- randomized controlled trial by propensity score matching (PSM). One hundred twelve community-dwelling older people who were recruited from the local community, participated in a beauty care program that consisted of two training sessions per month for 3 months and daily enforcement of facial skin care (intervention group). Seven hundred fifty-nine participants who received a comprehensive geriatric assessment were treated as a control group. Sex, age, BMI, lifestyle habits, hand grip strength, walking speed, skeletal muscle mass, bone density, medical history and life function (Kihon Checklist) were matched by the PSM method. We compared the subjects' self-rated health, depressive mood status (self-rating depression scale: SDS), and the frequency of going outdoors in the intervention and control groups before and after intervention. The improvements of SDS were significantly greater in the intervention group than in the control group. The self-rated health and the frequency of going outdoors were maintained in the intervention group but were significantly decreased in the control group. We conclude that beauty care is effective for maintaining and improving the self-rated health and depression status of community-dwelling older people and that it may help prolong healthy life expectancy.

  9. Optimization of scintillator loading with the tellurium-130 isotope for long-term stability

    Science.gov (United States)

    Duhamel, Lauren; Song, Xiaoya; Goutnik, Michael; Kaptanoglu, Tanner; Klein, Joshua; SNO+ Collaboration

    2017-09-01

    Tellurium-130 was selected as the isotope for the SNO + neutrinoless double beta decay search, as 130Te decays to 130Xe via double beta decay. Linear alkyl benzene(LAB) is the liquid scintillator for the SNO + experiment. To load tellurium into scintillator, it is combined with 1,2-butanediol to form an organometallic complex, commonly called tellurium butanediol (TeBD). This study focuses on maximizing the percentage of tellurium loaded into scintillator and evaluates the complex's long-term stability. Studies on the effect of nucleation due to imperfections in the detector's surface and external particulates were employed by filtration and induced nucleation. The impact of water on the stability of TeBD complex was evaluated by liquid-nitrogen sparging, variability in pH and induced humidity. Alternative loading methods were evaluated, including the addition of stability-inducing organic compounds. Samples of tellurium-loaded scintillator were synthesized, treated, and consistently monitored in a controlled environment. It was found that the hydronium ions cause precipitation in the loaded scintillator, demonstrating that water has a detrimental effect on long-term stability. Optimization of loaded scintillator stability can contribute to the SNO + double beta decay search.

  10. Stability measures in arid ecosystems

    Science.gov (United States)

    Nosshi, M. I.; Brunsell, N. A.; Koerner, S.

    2015-12-01

    Stability, the capacity of ecosystems to persist in the face of change, has proven its relevance as a fundamental component of ecological theory. Here, we would like to explore meaningful and quantifiable metrics to define stability, with a focus on highly variable arid and semi-arid savanna ecosystems. Recognizing the importance of a characteristic timescale to any definition of stability, our metrics will be focused scales from annual to multi-annual, capturing different aspects of stability. Our three measures of stability, in increasing order of temporal scale, are: (1) Ecosystem resistance, quantified as the degree to which the system maintains its mean state in response to a perturbation (drought), based on inter-annual variability in Normalized Difference Vegetation Index (NDVI). (2) An optimization approach, relevant to arid systems with pulse dynamics, that models vegetation structure and function based on a trade off between the ability to respond to resource availability and avoid stress. (3) Community resilience, measured as species turnover rate (β diversity). Understanding the nature of stability in structurally-diverse arid ecosystems, which are highly variable, yields theoretical insight which has practical implications.

  11. Methods of solving of the optimal stabilization problem for stationary smooth control systems. Part I

    Directory of Open Access Journals (Sweden)

    G. Kondrat'ev

    1999-10-01

    Full Text Available In this article some ideas of Hamilton mechanics and differential-algebraic Geometry are used to exact definition of the potential function (Bellman-Lyapunov function in the optimal stabilization problem of smooth finite-dimensional systems.

  12. Dynamics in microbial communities: Unraveling mechanisms to identify principles

    Energy Technology Data Exchange (ETDEWEB)

    Konopka, Allan; Lindemann, Stephen R.; Fredrickson, Jim K.

    2015-07-01

    Diversity begets higher order properties such as functional stability and robustness in microbial communities, but principles that inform conceptual (and eventually predictive) models of community dynamics are lacking. Recent work has shown that selection as well as dispersal and drift shape communities, but the mechanistic bases for assembly of communities and the forces that maintain their function in the face of environmental perturbation are not well understood. Conceptually, some interactions among community members could generate endogenous dynamics in composition, even in the absence of environmental changes. These endogenous dynamics are further perturbed by exogenous forcing factors to produce a richer network of community interactions, and it is this “system” that is the basis for higher order community properties. Elucidation of principles that follow from this conceptual model requires identifying the mechanisms that (a) optimize diversity within a community and (b) impart community stability. The network of interactions between organisms can be an important element by providing a buffer against disturbance beyond the effect of functional redundancy, as alternative pathways with different combinations of microbes can be recruited to fulfill specific functions.

  13. Financial stability, wealth effects and optimal macroeconomic policy combination in the United Kingdom: A new-Keynesian dynamic stochastic general equilibrium framework

    Directory of Open Access Journals (Sweden)

    Muhammad Ali Nasir

    2016-12-01

    Full Text Available This study derives an optimal macroeconomic policy combination for financial sector stability in the United Kingdom by employing a New Keynesian Dynamic Stochastic General Equilibrium (NK-DSGE framework. The empirical results obtained show that disciplined fiscal and accommodative monetary policies stance is optimal for financial sector stability. Furthermore, fiscal indiscipline countered by contractionary monetary stance adversely affects financial sector stability. Financial markets, e.g. stocks and Gilts show a short-term asymmetric response to macroeconomic policy interaction and to each other. The asymmetry is a reflection of portfolio adjustment. However in the long-run, the responses to suggested optimal policy combination had homogenous effects and there was evidence of co-movement in the stock and Gilt markets.

  14. Analysis and Optimization of Entry Stability in Underground Longwall Mining

    Directory of Open Access Journals (Sweden)

    Yubing Gao

    2017-11-01

    Full Text Available For sustainable utilization of limited coal resources, it is important to increase the coal recovery rate and reduce mine accidents, especially those occurring in the entry (gateroad. Entry stabilities are vital for ventilation, transportation and other essential services in underground coal mining. In the present study, a finite difference model was built to investigate stress evolutions around the entry, and true triaxial tests were carried out at the laboratory to explore entry wall stabilities under different mining conditions. The modeling and experimental results indicated that a wide coal pillar was favorable for entry stabilities, but oversize pillars caused a serious waste of coal resources. As the width of the entry wall decreased, the integrated vertical stress, induced by two adjacent mining panels, coupled with each other and experienced an increase on the entry wall, which inevitably weakened the stability of the entry. Therefore, mining with coal pillars always involves a tradeoff between economy and safety. To address this problem, an innovative non-pillar mining technique by optimizing the entry surrounding structures was proposed. Numerical simulation showed that the deformation of the entry roof decreased by approximately 66% after adopting the new approach, compared with that using the conventional mining method. Field monitoring indicated that the stress condition of the entry was significantly improved and the average roof pressure decreased by appropriately 60.33% after adopting the new technique. This work provides an economical and effective approach to achieve sustainable exploitation of underground coal resources.

  15. Affective profiles in Italian high school students: life satisfaction, psychological well-being, self-esteem, and optimism

    Directory of Open Access Journals (Sweden)

    Annamaria eDi Fabio

    2015-09-01

    Full Text Available The affective profiles model distinguishes between individuals who are self-fulfilling (high positive affect, low negative affect, high affective (high positive affect, high negative affect, low affective (low positive affect, low negative affect, and self-destructive (low positive affect, high negative affect. The literature shows that the affective profiles model has been used with Swedish people in particular in order to determine differences among profiles in relation to life satisfaction, psychological well-being, self-esteem, and optimism. The present research investigated these differences in Italian high school students. Two studies were conducted: the first with 156 Italian high school students and the second with 148 Italian high school students. The first study analyzed differences among affective profiles with regard to life satisfaction and psychological well-being while the second study analyzed differences among affective profiles with regard to self-esteem and optimism. In the first study, the Positive and Negative Affect Schedule (PANAS, the Satisfaction With Life Scale (SWLS, and the Meaningful Life Measure (MLM were administered to the participants. In the second study, the Positive and Negative Affect Schedule (PANAS, the Self-Esteem Scale (SES, the Life Orientation Test - revised (LOT-r were administered to the participants. The results of the first study showed that, with respect to the other profiles, the self-fulfilling participants had greater life satisfaction and psychological well-being. The results of the second study showed that, with respect to the other profiles, the self-fulfilling participants had higher self-esteem and optimism. These results revealed differences among affective profiles regarding life satisfaction, psychological well-being, self-esteem, and optimism in the Italian context as well thereby offering new possibilities for cross-cultural research and for enhancing self-fulfilling profiles.

  16. Long-Term Condition Self-Management Support in Online Communities: A Meta-Synthesis of Qualitative Papers

    Science.gov (United States)

    Vassilev, Ivaylo; Kennedy, Anne; Rogers, Anne

    2016-01-01

    Background Recent years have seen an exponential increase in people with long-term conditions using the Internet for information and support. Prior research has examined support for long-term condition self-management through the provision of illness, everyday, and emotional work in the context of traditional offline communities. However, less is known about how communities hosted in digital spaces contribute through the creation of social ties and the mobilization of an online illness “workforce.” Objective The aim was to understand the negotiation of long-term condition illness work in patient online communities and how such work may assist the self-management of long-term conditions in daily life. Methods A systematic search of qualitative papers was undertaken using various online databases for articles published since 2004. A total of 21 papers met the inclusion criteria of using qualitative methods and examined the use of peer-led online communities for those with a long-term condition. A qualitative meta-synthesis was undertaken and the review followed a line of argument synthesis. Results The main themes identified in relation to the negotiation of self-management support were (1) redressing offline experiential information and knowledge deficits, (2) the influence of modeling and learning behaviors from others on self-management, (3) engagement that validates illness and negates offline frustrations, (4) tie formation and community building, (5) narrative expression and cathartic release, and (6) dissociative anonymity and invisibility. These translated into a line of argument synthesis in which four network mechanisms for self-management support in patient online communities were identified. These were (1) collective knowledge and identification through lived experience; (2) support, information, and engagement through readily accessible gifting relationships; (3) sociability that extends beyond illness; and (4) online disinhibition as a facilitator

  17. Self-regulated learning and science achievement in a community college

    Science.gov (United States)

    Maslin, (Louisa) Lin-Yi L.

    Self-regulated learning involves students' use of strategies and skills to adapt and adjust towards achievement in school. This research investigates the extent to which self-regulated learning is employed by community college students, and also the correlates of self-regulated learning: Is it used more by students in advanced science classes or in some disciplines? Is there a difference in the use of it by students who complete a science course and those who do not? How does it relate to GPA and basic skills assessments and science achievement? Does it predict science achievement along with GPA and assessment scores? Community college students (N = 547) taking a science course responded to the Motivated Strategies for Learning Questionnaire (MSLQ). The scales measured three groups of variables: (1) cognitive strategies (rehearsal, elaboration, organization, and critical thinking); (2) metacognitive self-regulation strategies (planning, monitoring, and self-regulation); and (3) resource management strategies (time and study environment, effort regulation, peer learning, and help-seeking). Students' course scores, college GPA, and basic skills assessment scores were obtained from faculty and college records. Students who completed a science course were found to have higher measures on cumulative college GPAs and assessment scores, but not on self-regulated learning. Self-regulated learning was found not to be used differently between students in the advanced and beginning science groups, or between students in different disciplines. The exceptions were that the advanced group scored higher in critical thinking but lower in effort regulation than the beginning group. Course achievement was found to be mostly unrelated to self-regulated learning, except for several significant but very weak and negative relationships in elaboration, self-regulation, help-seeking, and effort regulation. Cumulative GPA emerged as the only significant predictor of science achievement

  18. Self-medication in Central Saudi Arabia. Community pharmacy consumers' perspectives.

    Science.gov (United States)

    Aljadhey, Hisham; Assiri, Ghada A; Mahmoud, Mansour A; Al-Aqeel, Sinaa; Murray, Michael

    2015-03-01

    To determine the prevalence of self-medication and assess the knowledge, attitudes, and perception of consumers toward self-medication. This cross-sectional survey was conducted over 4 weeks in May 2011 in Riyadh city, Kingdom of Saudi Arabia. Community pharmacies within 5 areas of the city (North, South, West, East, and Middle) were randomly selected for the study. All consumers were approached to participate in the study, with the exception of those buying cosmetic and medicinal equipments. A validated self-administered questionnaire was used to collect the data. A total of 538 out of 707 consumers attending community pharmacies in Riyadh city, agreed to participate in the study. Most responders were male (73%), 23-33 years old (35%), and college graduates (42%). A total of 285 medications were bought without a prescription. Of these, 149 (49%) medications should be dispensed by prescription only, and 155 (51%) were over the counter medications. The most common prescription medications dispensed without prescriptions were antibiotics (22%) and analgesics/antipyretics (19%). The most common reasons for buying medications without a prescription were that the symptoms were too minor to visit a doctor (54%), time saving (40%), and minor illnesses for which the participants knew the required treatment (40%). Overall, most participants had poor knowledge, and negative perceptions regarding self-medication. More than 68% of participants did not know whether the medicine they bought is a prescription-only or over the counter medication. Irresponsible self-medication is common in Saudi Arabia. Future studies should focus on improving the consumers' awareness of self-medication and the proper use of medications.

  19. Game theory and extremal optimization for community detection in complex dynamic networks.

    Science.gov (United States)

    Lung, Rodica Ioana; Chira, Camelia; Andreica, Anca

    2014-01-01

    The detection of evolving communities in dynamic complex networks is a challenging problem that recently received attention from the research community. Dynamics clearly add another complexity dimension to the difficult task of community detection. Methods should be able to detect changes in the network structure and produce a set of community structures corresponding to different timestamps and reflecting the evolution in time of network data. We propose a novel approach based on game theory elements and extremal optimization to address dynamic communities detection. Thus, the problem is formulated as a mathematical game in which nodes take the role of players that seek to choose a community that maximizes their profit viewed as a fitness function. Numerical results obtained for both synthetic and real-world networks illustrate the competitive performance of this game theoretical approach.

  20. The community feeling versus anxiety, self-esteem and well-being – introductory research

    Directory of Open Access Journals (Sweden)

    Kałużna-Wielobób Alina

    2017-06-01

    Full Text Available In accordance with the concept of A. Adler (1933/1986 - the community feeling is an individual characteristic which is relatively stable throughout life. It refers to an inner relationship of one person with other people: a feeling of unity with others or separation from others. People with high community feeling are motivated in their actions by striving towards the common good, whereas people with low community feeling intend to exhibit their superiority over others in their actions, which would allow them to compensate for their inner feeling of inferiority. On the basis of the Adler concept the following hypotheses were formulated: There is a negative connection between the community feeling and anxiety. The community feeling is positively connected with self-esteem and psychological well-being. A slight increase in the community feeling can be observed with age. The community feeling increases in the age of middle adulthood. 585 people between 20 to 65 years of age were examined. Methods: Community Feeling Questionnaire, State-Trait Anxiety Inventory, Rosenberg Self-Esteem Scale, Ryff Scales of Psychological Well-Being. The hypotheses assumed were verified.

  1. A self-setting particle-stabilized porous ceramic panel prepared from commercial cement and loaded with carbon for potential radar'absorbing applications

    Directory of Open Access Journals (Sweden)

    Jang-Hoon Ha

    2018-03-01

    Full Text Available Porous ceramic materials are in a current research focus because of their outstanding thermal stability, chemical stability and lightweight. Recent research has widened the range of applications to radar absorption to utilize the advantages of porous ceramic materials. There has been long-standing interest in the development of lightweight radar-absorbing materials for military applications such as camouflaging ground-based facilities against airborne radar detection. Therefore, in this study, a novel lightweight radar-absorbing material for X-band frequencies was developed using a self-setting particle-stabilized porous ceramic panel composited with carbon. The panel was prepared using a commercial calcium aluminate cement (as a self-setting matrix, zeolite 13X particles with propyl gallate (as a particle-stabilized pore former and carbon (as a radar-absorbing material. The panel contained macropores approximately 200 to 400 µm in size formed by zeolite 13X particles that are irreversibly adsorbed at liquid-gas interfaces. The self-setting particle-stabilized porous ceramic panels were characterized by scanning electron microscopy, mercury porosimetry, physisorption analysis, capillary flow porosimetry and network analysis. When 0.2 wt.% carbon was added to a self-setting particle-stabilized porous ceramic panel to fabricate a composite 7 mm thick, the maximum reflection loss was −11.16 dB at 12.4 GHz. The effects of the amount of added carbon and the thickness variation of a self-setting particle-stabilized porous ceramic panel on the radar-absorbing properties remain important issues for further research.

  2. Effect of self-rated health on cognitive performance in community dwelling elderly

    NARCIS (Netherlands)

    Jelicic, M; Kempen, GIJM

    1999-01-01

    The objective of this study was to examine the effect of self-reported health on. cognitive function in community dwelling elderly (N = 4,528). Research participants were divided into four groups with regard to self-rated health. Statistically controlling for the effects of depression, age, and

  3. An Improved Particle Swarm Optimization Algorithm and Its Application in the Community Division

    Directory of Open Access Journals (Sweden)

    Jiang Hao

    2016-01-01

    Full Text Available With the deepening of the research on complex networks, the method of detecting and classifying social network is springing up. In this essay, the basic particle swarm algorithm is improved based on the GN algorithm. Modularity is taken as a measure of community division [1]. In view of the dynamic network community division, scrolling calculation method is put forward. Experiments show that using the improved particle swarm optimization algorithm can improve the accuracy of the community division and can also get higher value of the modularity in the dynamic community

  4. Cyber-Porn Dependence: Voices of Distress in an Italian Internet Self-Help Community

    Science.gov (United States)

    Cavaglion, Gabriel

    2009-01-01

    This study analyzes narratives of cyber-porn users and defines major patterns of distress as self-reported by contributors to a self-help group in the Internet. It applies narrative analysis methodology to 2000 messages sent by 302 members of an Italian self-help Internet community for cyber-porn dependents ("noallapornodipendenza").…

  5. Curcumin-loaded self-nanomicellizing solid dispersion system: part I: development, optimization, characterization, and oral bioavailability.

    Science.gov (United States)

    Parikh, Ankit; Kathawala, Krishna; Song, Yunmei; Zhou, Xin-Fu; Garg, Sanjay

    2018-05-29

    Curcumin (CUR) is considered as one of the most bioactive molecules ever discovered from nature due to its proven anti-inflammatory and antioxidant in both preclinical and clinical studies. Despite its proven safety and efficacy, the clinical translation of CUR into a useful therapeutic agent is still limited due to its poor oral bioavailability. To overcome its limitation and enhance oral bioavailability by improving its aqueous solubility, stability, and intestinal permeability, a novel CUR formulation (NCF) was developed using the self-nanomicellizing solid dispersion strategy. From the initial screening of polymers for their potential to improve the solubility and stability, Soluplus (SOL) was selected. The optimized NCF demonstrated over 20,000-fold improvement in aqueous solubility as a result of amorphization, hydrogen bonding interaction, and micellization determined using differential scanning calorimetry, X-ray diffraction, scanning electron microscopy, Fourier transform infrared spectroscopy, nuclear magnetic resonance, dynamic light scattering, and transmission electron microscopy. Moreover, the greater stabilizing effect in alkaline pH and light was observed. Furthermore, significant enhancement of dissolution and permeability of CUR across everted sacs of rat small intestine were noticed. Pharmacokinetic studies demonstrated that the oral bioavailability of CUR was increased 117 and 17-fold in case of NCF and physical mixture of CUR and SOL compared to CUR suspension. These results suggest NCF identified as a promising new approach for repositioning of CUR for pharmaceutical application by enhancing the oral bioavailability of CUR. The findings herein stimulate further in vivo evaluations and clinical tests of NCF.

  6. Stabilization of electron beam spot size by self bias potential

    International Nuclear Information System (INIS)

    Kwan, T.J.T.; Moir, D.C.; Snell, C.M.; Kang, M.

    1998-01-01

    In high resolution flash x-ray imaging technology the electric field developed between the electron beam and the converter target is large enough to draw ions from the target surface. The ions provide fractional neutralization and cause the electron beam to focus radially inward, and the focal point subsequently moves upstream due to the expansion of the ion column. A self-bias target concept is proposed and verified via computer simulation that the electron charge deposited on the target can generate an electric potential, which can effectively limit the ion motion and thereby stabilize the growth of the spot size. A target chamber using the self bias target concept was designed and tested in the Integrated Test Stand (ITS). The authors have obtained good agreement between computer simulation and experiment

  7. Enhanced Nanotribology and Optimal Self-lubrication in Novel Polymer-Metal Composites

    Science.gov (United States)

    Seam, Alisha; Brostow, Witold; Olea-Mejia, Oscar

    2006-10-01

    Cheaper to produce, light-weight polymeric materials with improved micro and nano-scale tribological characteristics ar gradually replacing the heavier metals in gears, cams, ball-bearings, chains, and other critical machine components which operate under high stress, experience substantial sliding friction and wear, and require external lubrication regimes. Application of such high-performance synthetic materials in a whole range of machinery, manufacturing, aerospace and transportation industries would produce far reaching economic, energy conservation and environmental benefits. This paper devises and investigates a novel and previously untested method of developing self-lubricating and wear-resistant polymer based materials (PBMs) by blending a polymer with small proportions of a metallic additive. Tribological experiments establish that as increasing proportions of the metallic additive Iron (Fe) are added to the polymeric base polyethylene (PE), the friction and wear of the resulting composite (PE-Fe) experiences significant decline until an optimal value of 3 to 5 % Iron and then stabilize. Theoretical analysis reveals this phenomenon to likely be a result of the nano-structural formation of a lubricating oxide layer on surface of the polymer-metal composite. Furthermore, the oxide layer prevented significant degradation of the viscoelastic scratch-recovery of the base polymer, even with 10 percent metal additive (Fe) in the composite samples.

  8. Freedom, invisibility, and community: a qualitative study of self-identification with asexuality.

    Science.gov (United States)

    MacNeela, Pádraig; Murphy, Aisling

    2015-04-01

    A significant body of research is now emerging on the subjective meaning of asexuality. This study explored how self-identification as asexual is managed, both as a threat to the self-concept and a source of personal meaning. A total of 66 self-identified asexuals were recruited from an asexuality internet community and responded to open-ended questions on an online survey. Of these, 31 participants identified as female, 15 as male, 18 gave a different label such as genderqueer or androgynous, and two did not provide information on gender. A thematic analysis of the transcripts resulted in three themes. Socially, asexuality attracted denial and resistance due to incompatibility with heteronormative societal expectations. Despite the threat to self-integrity arising from asexuality being socially rejected, it was typically assimilated as a valued and meaningful orientation on an intra-personal level, aided by information and support from the online community. A second level of threat to self arose whereby other self-identifications, especially gender, had to be reconciled with a non-sexual persona. The accommodation made to other elements of the self was reflected in complex sub-identities. The findings were interpreted using identity process theory to understand how threats arising from self-identifying as asexual are managed. Although asexuality emerges as an orientation to sexuality that can be reconciled with the self, its invisibility or outright rejection in society constitute an on-going challenge.

  9. The Evolving Contingency Contracting Market: Private Sector Self regulation and United States Government Monitoring of Procurement of Stability Operations Services

    Science.gov (United States)

    2016-01-01

    statements of work would be useful in ensuring ethical govern- ment procurement practices. Conclusions The United States conducts diplomatic, defense...THE EVOLVING CONTINGENCY CONTRACTING MARKET: PRIVATE SECTOR SELF-REGULATION AND UNITED STATES GOVERNMENT MONITORING OF PROCUREMENT OF STABILITY...MARKET: PRIVATE SECTOR SELF-REGULATION AND UNITED STATES GOVERNMENT MONITORING OF PROCUREMENT OF STABILITY OPERATIONS SERVICES Whitney Grespin January

  10. Barriers to Quality Care for Dying Patients in Rural Communities

    Science.gov (United States)

    Van Vorst, Rebecca F.; Crane, Lori A.; Barton, Phoebe Lindsey; Kutner, Jean S.; Kallail, K. James; Westfall, John M.

    2006-01-01

    Context: Barriers to providing optimal palliative care in rural communities are not well understood. Purpose: To identify health care personnel's perceptions of the care provided to dying patients in rural Kansas and Colorado and to identify barriers to providing optimal care. Methods: An anonymous self-administered survey was sent to health care…

  11. Self-medication with antibiotics in the Republic of Srpska community pharmacies: pharmacy staff behavior.

    Science.gov (United States)

    Marković-Peković, Vanda; Grubiša, Nataša

    2012-10-01

    Self-medication with antibiotics adds to the global risk of increased spread of bacterial resistance. Attitudes and behavior of health professionals also may reinforce self-medication with antibiotics. The aim of this study was to determine whether self-medication with antibiotics is possible in our community pharmacies and to what extent, and to evaluate the behavior and service of pharmacy health professionals regarding non-prescription antibiotic dispensation. An observational, cross-section study was conducted, and pseudo-patient methodology was used to establish the kind of professional service provided in case of patient's explicit demand to buy an antibiotic for treatment of self-diagnosed upper respiratory tract infection. Of the total 318 community pharmacies, 131 (41%) were visited and included in the study. Non-prescription antibiotics were dispensed in 76 (58%) pharmacies. Counseling and symptomatic therapy was offered in 88 (67%) pharmacies. In 25% of pharmacies, no symptomatic therapy was offered; instead, only an antibiotic was sold. Amoxicillin was sold in 85% of cases and, mostly, the one of 1.30 Euro per pack. Both oral and written use instructions were given in 78% cases, whereas none was given in 3% of cases. Self-medication with antibiotics occurs in our community pharmacies, despite being illegal. Pharmacy staff behavior can be a factor that puts patients at risk for self-medication with antibiotics. Community pharmacies are failing their tasks in enhancing rational use of antibiotics. Such a practice may be a consequence of weak enforcement and control over the legislation and professional standards. Copyright © 2012 John Wiley & Sons, Ltd.

  12. Dc microgrid stabilization through fuzzy control of interleaved, heterogeneous storage elements

    Science.gov (United States)

    Smith, Robert David

    As microgrid power systems gain prevalence and renewable energy comprises greater and greater portions of distributed generation, energy storage becomes important to offset the higher variance of renewable energy sources and maximize their usefulness. One of the emerging techniques is to utilize a combination of lead-acid batteries and ultracapacitors to provide both short and long-term stabilization to microgrid systems. The different energy and power characteristics of batteries and ultracapacitors imply that they ought to be utilized in different ways. Traditional linear controls can use these energy storage systems to stabilize a power grid, but cannot effect more complex interactions. This research explores a fuzzy logic approach to microgrid stabilization. The ability of a fuzzy logic controller to regulate a dc bus in the presence of source and load fluctuations, in a manner comparable to traditional linear control systems, is explored and demonstrated. Furthermore, the expanded capabilities (such as storage balancing, self-protection, and battery optimization) of a fuzzy logic system over a traditional linear control system are shown. System simulation results are presented and validated through hardware-based experiments. These experiments confirm the capabilities of the fuzzy logic control system to regulate bus voltage, balance storage elements, optimize battery usage, and effect self-protection.

  13. Water-in-Oil Microemulsions for Protein Delivery: Loading Optimization and Stability.

    Science.gov (United States)

    Perinelli, Diego R; Cespi, Marco; Pucciarelli, Stefania; Vincenzetti, Silvia; Casettari, Luca; Lam, Jenny K W; Logrippo, Serena; Canala, Elisa; Soliman, Mahmoud E; Bonacucina, Giulia; Palmieri, Giovanni F

    2017-01-01

    Microemulsions are attractive delivery systems for therapeutic proteins and peptides due to their ability to enhance bioavailability. Although different proteins and peptides have been successfully delivered through such ternary systems, no information can be found about protein loading and the formulation stability when such microemulsions are prepared with pharmaceuticallyapproved oils and surfactants. The aim of this work was to optimise a ternary system consisting of water/ ethyl oleate/Span® 80-Tween® 80 and to determine its protein loading capacity and stability, using bovine serum albumin (BSA) as a model of biomolecule. The optimization was carried out using a Central Composite Design and all the prepared formulations were characterised through dynamic light scattering, rheology, optical and polarized microscopy. Subsequently, the maximum loading capacity was determined and the stability of the final microemulsion with the highest content of protein was followed over six months. To investigate the structural features of the protein, BSA was recovered from the microemulsion and analysed through fluorescence spectroscopy. After incorporation of the protein in the microemulsion, a decrease of its aqueous solubility was observed. However, the formulation remained stable over six months and the native-like state of the recovered protein was demonstrated by fluorescence spectroscopy Conclusion: This study demonstrated the feasibility of preparing microemulsions with the highest content of protein and their long-term stability. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

  14. Stability of concentration-related self-interstitial atoms in fusion material tungsten

    Science.gov (United States)

    Hong, Zhang; Shu-Long, Wen; Min, Pan; Zheng, Huang; Yong, Zhao; Xiang, Liu; Ji-Ming, Chen

    2016-05-01

    Based on the density functional theory, we calculated the structures of the two main possible self-interstitial atoms (SIAs) as well as the migration energy of tungsten (W) atoms. It was found that the difference of the and formation energies is 0.05-0.3 eV. Further analysis indicated that the stability of SIAs is closely related to the concentration of the defect. When the concentration of the point defect is high, SIAs are more likely to exist, SIAs are the opposite. In addition, the vacancy migration probability and self-recovery zones for these SIAs were researched by making a detailed comparison. The calculation provided a new viewpoint about the stability of point defects for self-interstitial configurations and would benefit the understanding of the control mechanism of defect behavior for this novel fusion material. Project supported by the Fundamental Research Funds for the Central Universities of Ministry of Education of China (Grant Nos. A0920502051411-5 and 2682014ZT30), the Program of International Science and Technology Cooperation, China (Grant No. 2013DFA51050), the National Magnetic Confinement Fusion Science Program, China (Grant Nos. 2011GB112001 and 2013GB110001), the National High Technology Research and Development Program of China (Grant No. 2014AA032701), the National Natural Science Foundation of China (Grant No. 11405138), the Southwestern Institute of Physics Funds, China, the Western Superconducting Technologies Company Limited, China, the Qingmiao Plan of Southwest Jiaotong University, China (Grant No. A0920502051517-6), and the China Postdoctoral Science Foundation (Grant No. 2014M560813).

  15. Level and Stability of Self-Esteem as Predictors of Children's Intrinsic Motivation and Reasons for Anger.

    Science.gov (United States)

    Waschull, Stefanie B.; Kernis, Michael H.

    1996-01-01

    Examines the extent to which level and stability of fifth-grade children's self-esteem predicted achievement motivation and reasons for anger. Findings indicate that the more unstable the children's self-esteem, the lower their scores on measures of curiosity/interest and preference for challenge, and the greater the likelihood that they would…

  16. Increasing Student Achievement and Improving Self-Esteem through a Community Building Intervention

    Science.gov (United States)

    Lupo, Concetta M.

    2012-01-01

    This study focused on improving students' self-esteem through community building at an elementary school in a low socioeconomic community where over 55% of the students live below the poverty line. Orefield and Yun state in their 1999 article, "Resegregation of America's schools," "school level poverty is related to many…

  17. Hybrid Particle Swarm Optimization based Day-Ahead Self-Scheduling for Thermal Generator in Competitive Electricity Market

    DEFF Research Database (Denmark)

    Pindoriya, Naran M.; Singh, S.N.; Østergaard, Jacob

    2009-01-01

    in day-ahead energy market subject to operational constraints and 2) at the same time, to minimize the risk due to uncertainty in price forecast. Therefore, it is a conflicting bi-objective optimization problem which has both binary and continuous optimization variables considered as constrained mixed......This paper presents a hybrid particle swarm optimization algorithm (HPSO) to solve the day-ahead self-scheduling for thermal power producer in competitive electricity market. The objective functions considered to model the self-scheduling problem are 1) to maximize the profit from selling energy...... integer nonlinear programming. To demonstrate the effectiveness of the proposed method for self-scheduling in a day-ahead energy market, the locational margin price (LMP) forecast uncertainty in PJM electricity market is considered. An adaptive wavelet neural network (AWNN) is used to forecast the day...

  18. Transition to motherhood and the self: measurement, stability, and change.

    Science.gov (United States)

    Ruble, D N; Brooks-Gunn, J; Fleming, A S; Fitzmaurice, G; Stangor, C; Deutsch, F

    1990-03-01

    Different ways of conceptualizing and measuring change in attitudes during transition to motherhood are examined. A series of analyses was performed on data from a cross-sectional sample (N = 667) and a smaller longitudinal sample (n = 48) to demonstrate sound psychometric properties for 2 new scales and to show construct comparability across different phases of childbearing. For Childbearing Attitudes Questionnaire, results demonstrated equality of covariance for 16 scales and comparability of structure and meaning of 4 higher order factors--identification with motherhood, social orientation, self-confidence, and negative aspects of giving birth. For Mothering Self-Definition Questionnaire, results demonstrated equality of covariance of 5 scales and comparability of structure and meaning of a single higher order factor, interpreted as reflecting positive feelings about one's mothering characteristics. Analyses of correlations and mean differences identified areas of change and stability.

  19. Felt stigma and self-esteem among psychiatric hospital outdoor and community camp attending patients

    Directory of Open Access Journals (Sweden)

    Shantna Kumari

    2014-01-01

    Full Text Available Background: Self-stigma of people with mental illness is a major obstacle to recovery, limiting opportunities and undermining self-esteem. Aim: The aim of this study is to compare felt stigma and self-esteem in psychiatric patients receiving treatment from hospital outdoor clinic or from Community Outreach Program (COP. Materials and Methods: This cross-sectional study was conducted on psychiatric patients who were on outpatient treatment for at least 6 months, but had never been hospitalized. The study sample included 130 patients receiving outdoor treatment from a Psychiatric Hospital and a matched group of 140 patients receiving treatment from COP of the same hospital. Demographic and clinical details of the patients were recorded on a specially designed proforma. Modified felt stigma scale and Rosenberg self-esteem scale were used to assess stigma and self-esteem, respectively. Results: On the modified felt stigma scale, the mean (±standard deviation [SD] score of psychiatric hospital outpatients (31.89 ± 6.51 was significantly higher than the scores of patients attending COP (29.20 ± 6.80. On Rosenberg self-esteem scale, mean (±SD scores of patients with psychosis (17.98 ± 1.69 was significantly lower compared to scores of patients with epilepsy (21.83 ± 1.60. There was no significant correlation between stigma and self-esteem. Conclusion: As psychiatric hospital outpatients have significantly more self-stigma when compared to patients attending community outreach camps, the availability of more community outreach camps along with educating people about psychiatric illnesses may help in lowering stigma of psychiatric disorders.

  20. Inclusion of College Community in the Self: A Longitudinal Study of the Role of Self-Expansion in Students' Satisfaction

    Science.gov (United States)

    Branand, Brittany; Mashek, Debra; Wray-Lake, Laura; Coffey, John K.

    2015-01-01

    Consistent with predictions derived from the self-expansion model, this 3-year longitudinal study found that participation in more college groups during sophomore year predicted increases in inclusion of the college community in the self at the end of junior year, which further predicted increases in satisfaction with the college experience at the…

  1. Relationships between depressive symptoms and perceived social support, self-esteem, & optimism in a sample of rural adolescents.

    Science.gov (United States)

    Weber, Scott; Puskar, Kathryn Rose; Ren, Dianxu

    2010-09-01

    Stress, developmental changes and social adjustment problems can be significant in rural teens. Screening for psychosocial problems by teachers and other school personnel is infrequent but can be a useful health promotion strategy. We used a cross-sectional survey descriptive design to examine the inter-relationships between depressive symptoms and perceived social support, self-esteem, and optimism in a sample of rural school-based adolescents. Depressive symptoms were negatively correlated with peer social support, family social support, self-esteem, and optimism. Findings underscore the importance for teachers and other school staff to provide health education. Results can be used as the basis for education to improve optimism, self-esteem, social supports and, thus, depression symptoms of teens.

  2. Increasing Student Metacognition and Learning through Classroom-Based Learning Communities and Self-Assessment

    Directory of Open Access Journals (Sweden)

    Amy Siegesmund

    2016-05-01

    Full Text Available Student overconfidence challenges success in introductory biology. This study examined the impact of classroom learning communities and self-assessment on student metacognition and subsequent impact on student epistemological beliefs, behaviors, and learning. Students wrote weekly self-assessments reflecting on the process of learning and received individual feedback. Students completed a learning strategies inventory focused on metacognition and study behaviors at the beginning and end of the semester and a Student Assessment of their Learning Gains (SALG at the end of the semester. Results indicated significant changes in both metacognition and study behaviors over the course of the semester, with a positive impact on learning as determined by broad and singular measures. Self-assessments and SALG data demonstrated a change in student beliefs and behaviors. Taken together, these findings argue that classroom learning communities and self-assessment can increase student metacognition and change student epistemological beliefs and behaviors.

  3. Optimization of ultrasound-assisted extraction of pectinase enzyme from guava (Psidium guajava) peel: Enzyme recovery, specific activity, temperature, and storage stability.

    Science.gov (United States)

    Amid, Mehrnoush; Murshid, Fara Syazana; Manap, Mohd Yazid; Islam Sarker, Zaidul

    2016-01-01

    This study aimed to investigate the effects of the ultrasound-assisted extraction conditions on the yield, specific activity, temperature, and storage stability of the pectinase enzyme from guava peel. The ultrasound variables studied were sonication time (10-30 min), ultrasound temperature (30-50 °C), pH (2.0-8.0), and solvent-to-sample ratio (2:1 mL/g to 6:1 mL/g). The main goal was to optimize the ultrasound-assisted extraction conditions to maximize the recovery of pectinase from guava peel with the most desirable enzyme-specific activity and stability. Under the optimum conditions, a high yield (96.2%), good specific activity (18.2 U/mg), temperature stability (88.3%), and storage stability (90.3%) of the extracted enzyme were achieved. The optimal conditions were 20 min sonication time, 40 °C temperature, at pH 5.0, using a 4:1 mL/g solvent-to-sample ratio. The study demonstrated that optimization of ultrasound-assisted process conditions for the enzyme extraction could improve the enzymatic characteristics and yield of the enzyme.

  4. Community nurses and self-management of blood glucose.

    Science.gov (United States)

    Abbott, S; Burns, J; Gleadell, A; Gunnell, C

    2007-01-01

    Self-monitoring of blood glucose (SMBG) is commonly recommended to patients with diabetes, although the rationale for this is unclear. This small research project was designed to explore the reasons why nurses working in the community recommend SMBG. Seven interviews were carried out with community nurses caring primarily for housebound patients. Those interviewed believed that a sound evidence-base supported the recommendation that patients test their blood, but not urine, for glucose levels. Though nurses believed in the importance of patient choice and empowerment, the scope for these was limited among housebound patients. There was no evidence that patients understood how to respond to test results, or that comprehensive care planning was normal practice. Although small, this study suggests that nurses working in community settings may need to update their knowledge. It also suggests that a national debate is necessary to disseminate better the evidence about SMBG, and its implications for nursing practice.

  5. Measuring the emulsification dynamics and stability of self-emulsifying drug delivery systems.

    Science.gov (United States)

    Vasconcelos, Teófilo; Marques, Sara; Sarmento, Bruno

    2018-02-01

    Self-emulsifying drug delivery systems (SEDDS) are one of the most promising technologies in the drug delivery field, particularly for addressing solubility and bioavailability issues of drugs. The development of these drug carriers excessively relies in visual observations and indirect determinations. The present manuscript intended to describe a method able to measure the emulsification of SEDDS, both micro and nano-emulsions, able to measure the droplet size and to evaluate the physical stability of these formulations. Additionally, a new process to evaluate the physical stability of SEDDS after emulsification was also proposed, based on a cycle of mechanical stress followed by a resting period. The use of a multiparameter continuous evaluation during the emulsification process and stability was of upmost value to understand SEDDS emulsification process. Based on this method, SEDDS were classified as fast and slow emulsifiers. Moreover, emulsification process and stabilization of emulsion was subject of several considerations regarding the composition of SEDDS as major factor that affects stability to physical stress and the use of multicomponent with different properties to develop a stable and robust SEDDS formulation. Drug loading level is herein suggested to impact droplets size of SEDDS after dispersion and SEDDS stability to stress conditions. The proposed protocol allows an online measurement of SEDDS droplet size during emulsification and a rationale selection of excipients based on its emulsification and stabilization performance. Copyright © 2017. Published by Elsevier B.V.

  6. Tuning PID attitude stabilization of a quadrotor using particle swarm optimization (experimental

    Directory of Open Access Journals (Sweden)

    Khodja Mohammed Abdallah

    2017-01-01

    Full Text Available Proportional, Integral and Derivative (PID controllers are the most popular type of controller used in industrial applications because of their notable simplicity and effective implementation. However, manual tuning of these controllers is tedious and often leads to poor performance. The conventional Ziegler-Nichols (Z-N method of PID tuning was done experimentally enables easy identification stable PID parameters in a short time, but is accompanied by overshoot, high steady-state error, and large rise time. Therefore, in this study, the modern heuristics approach of Particle Swarm Optimization (PSO was employed to enhance the capabilities of the conventional Z-N technique. PSO with the constriction coefficient method experimentally demonstrated the ability to efficiently and effectively identify optimal PID controller parameters for attitude stabilization of a quadrotor.

  7. The relationships among work stress, strain and self-reported errors in UK community pharmacy.

    Science.gov (United States)

    Johnson, S J; O'Connor, E M; Jacobs, S; Hassell, K; Ashcroft, D M

    2014-01-01

    Changes in the UK community pharmacy profession including new contractual frameworks, expansion of services, and increasing levels of workload have prompted concerns about rising levels of workplace stress and overload. This has implications for pharmacist health and well-being and the occurrence of errors that pose a risk to patient safety. Despite these concerns being voiced in the profession, few studies have explored work stress in the community pharmacy context. To investigate work-related stress among UK community pharmacists and to explore its relationships with pharmacists' psychological and physical well-being, and the occurrence of self-reported dispensing errors and detection of prescribing errors. A cross-sectional postal survey of a random sample of practicing community pharmacists (n = 903) used ASSET (A Shortened Stress Evaluation Tool) and questions relating to self-reported involvement in errors. Stress data were compared to general working population norms, and regressed on well-being and self-reported errors. Analysis of the data revealed that pharmacists reported significantly higher levels of workplace stressors than the general working population, with concerns about work-life balance, the nature of the job, and work relationships being the most influential on health and well-being. Despite this, pharmacists were not found to report worse health than the general working population. Self-reported error involvement was linked to both high dispensing volume and being troubled by perceived overload (dispensing errors), and resources and communication (detection of prescribing errors). This study contributes to the literature by benchmarking community pharmacists' health and well-being, and investigating sources of stress using a quantitative approach. A further important contribution to the literature is the identification of a quantitative link between high workload and self-reported dispensing errors. Copyright © 2014 Elsevier Inc. All rights

  8. Patients' views and experiences of technology based self-management tools for the treatment of hypertension in the community: A qualitative study.

    Science.gov (United States)

    Glynn, Liam; Casey, Monica; Walsh, Jane; Hayes, Patrick S; Harte, Richard P; Heaney, David

    2015-09-09

    Patients with hypertension in the community frequently fail to meet treatment goals. The optimal way to organize and deliver care to hypertensive patients has not been clearly identified. The powerful on-board computing capacity of mobile devices, along with the unique relationship individuals have with newer technologies, suggests that they have the potential to influence behaviour. However, little is known regarding the views and experiences of patients using such technology to self-manage their hypertension and associated lifestyle behaviours. The aim of this study was to explore patients' views and experiences of using technology based self-management tools for the treatment of hypertension in the community. This focus group study was conducted with known hypertensive patients over 45 years of age who were recruited in a community setting in Ireland. Taped and transcribed semi-structured interviews with a purposeful sample involving 50 participants in six focus groups were used. Framework analysis was utilized to analyse the data. Four key inter-related themes emerged from the analysis: individualisation; trust; motivation; and communication. The globalisation of newer technologies has triggered many substantial and widespread behaviour changes within society, yet users are unique in their use and interactions with such technologies. Trust is an ever present issue in terms of its potential impact on engagement with healthcare providers and motivation around self-management. The potential ability of technology to influence motivation through carefully selected and tailored messaging and to facilitate a personalised flow of communication between patient and healthcare provider was highlighted. Newer technologies such as mobile devices and the internet have been embraced across the globe despite technological challenges and concerns regarding privacy and security. In the design and development of technology based self-management tools for the treatment of

  9. COMMUNITY DETERMINANTS OF IMMIGRANT SELF-EMPLOYMENT: HUMAN CAPITAL SPILLOVERS AND ETHNIC ENCLAVES

    OpenAIRE

    Liliana Sousa

    2013-01-01

    I find evidence that human capital spillovers have positive effects on the proclivity of low human capital immigrants to self-employ. Human capital spillovers within an ethnic community can increase the self-employment propensity of its members by decreasing the costs associated with starting and running a business (especially, transaction costs and information costs). Immigrants who do not speak English and those with little formal education are more likely to be self-employed if they reside...

  10. The self-concept and conjugal loss: evidence for structural change.

    Science.gov (United States)

    Montpetit, Mignon A; Bergeman, C S; Bisconti, Toni L

    2010-08-01

    The self-concept is often considered to be a personal resource that individuals may use to cope with life stressors, but little is known about how this entity might itself change in response to profound stress. The present study examines structural change in self-concept following conjugal loss in later life. Analyses were conducted on data collected from 57 widows every 4 months over the first 2 years post-loss. The first objective was to explore the adequacy of an operational definition of the self-concept as a latent construct lying at the confluence of self-esteem, perceived environmental mastery, and optimism. Because confirmatory factor analysis (CFA) supported this theoretically based conceptualization, the second objective of the study was to model stability and change in the structure of the self-concept over the 2-year study period. Results suggested that there is both stability and change in the self-system during the adjustment to major life stress.

  11. Optimal combustor dimensions for the catalytic combustion of methane-air mixtures in micro-channels

    International Nuclear Information System (INIS)

    Chen, Junjie; Song, Wenya; Xu, Deguang

    2017-01-01

    Highlights: • The effect of combustor dimensions on the combustion stability was elucidated. • Wall thermal properties are important for optimizing combustor dimensions. • The optimal wall thickness increases with flow velocity. • The optimal combustor length depends on the wall thermal conductivity. • Stability diagrams were constructed and design recommendations were made. - Abstract: This paper addresses the question of choosing appropriate combustor dimensions for the self-sustained catalytic combustion in parallel plate micro-channels. The combustion characteristics and stability of methane-air mixtures over platinum in catalytic micro-combustors were studied, using a two-dimensional computational fluid dynamics (CFD) model with detailed chemistry and transport. The effects of gap size, wall thickness, and combustor length on the combustion stability and combustor performance were explored to provide guidelines for optimal design of combustor dimensions. Combustion stability diagrams were constructed, and design recommendations were made. The effect of wall thermal conductivity on the mechanisms of extinction and blowout, and its implications on optimal combustor geometry were studied. It was shown that combustor dimensions are vital in determining the combustion stability of the system. The choice of appropriate combustor dimensions is crucial in achieving stable combustion, due to a rather narrow operating space determined by stability, material, and conversion constraints. The optimal gap size depends on whether the flow velocity or flow rate is kept constant. For most practical wall materials in the range of metals to highly conductive ceramics, larger combustors are more stable at a fixed flow velocity, whereas smaller combustors are recommended for a fixed flow rate at the expense of hot spots. The optimal wall thickness increases with flow velocity. Higher flow velocities can be sustained in combustors with low-conductivity materials using

  12. Sound speeds, cracking and the stability of self-gravitating anisotropic compact objects

    International Nuclear Information System (INIS)

    Abreu, H; Hernandez, H; Nunez, L A

    2007-01-01

    Using the concept of cracking we explore the influence that density fluctuations and local anisotropy have on the stability of local and non-local anisotropic matter configurations in general relativity. This concept, conceived to describe the behavior of a fluid distribution just after its departure from equilibrium, provides an alternative approach to consider the stability of self-gravitating compact objects. We show that potentially unstable regions within a configuration can be identified as a function of the difference of propagations of sound along tangential and radial directions. In fact, it is found that these regions could occur when, at a particular point within the distribution, the tangential speed of sound is greater than the radial one

  13. Permanence of Two Self-Managed Treatments of Overweight in University and Community Populations

    Science.gov (United States)

    And Others; Hall, Robert G.

    1974-01-01

    Males and females from community and university samples were assigned to two self-management treatments, nonspecific, or no-treatment controls. At six month follow-up, differences were not significant. Results are discussed in terms of conceptualizations of self-management and the utility of treatments employed. (Author)

  14. Self-Efficacy and Nutrition Education: A Study of the Effect of an Intervention with Faith Community Nurses.

    Science.gov (United States)

    Gotwals, Beth

    2018-02-01

    The faith community provides an important access point for practice focused on population health at a time when health issues such as obesity and overweight are affecting large number of Americans. The purpose of this study was to examine faith community nurses' self-efficacy perceptions following a nutrition educational intervention. A convenience sample of 92 faith community nurses were randomly assigned to experimental and control groups. The t-distribution analysis revealed significant differences between the nutrition knowledge self-efficacy (p = .016) and nutrition counseling self-efficacy (p = .010) post-test scores for the experimental and control groups. This type of educational intervention provides a model to be used with faith community nurses as they integrate faith and health in this setting.

  15. A Dynamic Combinatorial Approach for Identifying Side Groups that Stabilize DNA-Templated Supramolecular Self-Assemblies

    Directory of Open Access Journals (Sweden)

    Delphine Paolantoni

    2015-02-01

    Full Text Available DNA-templated self-assembly is an emerging strategy for generating functional supramolecular systems, which requires the identification of potent multi-point binding ligands. In this line, we recently showed that bis-functionalized guanidinium compounds can interact with ssDNA and generate a supramolecular complex through the recognition of the phosphodiester backbone of DNA. In order to probe the importance of secondary interactions and to identify side groups that stabilize these DNA-templated self-assemblies, we report herein the implementation of a dynamic combinatorial approach. We used an in situ fragment assembly process based on reductive amination and tested various side groups, including amino acids. The results reveal that aromatic and cationic side groups participate in secondary supramolecular interactions that stabilize the complexes formed with ssDNA.

  16. Can we measure daily tobacco consumption in remote indigenous communities? Comparing self-reported tobacco consumption with community-level estimates in an Arnhem Land study.

    Science.gov (United States)

    Clough, Alan R; MacLaren, David J; Robertson, Jan A; Ivers, Rowena G; Conigrave, Katherine M

    2011-03-01

    In remote Indigenous Australian communities measuring individual tobacco use can be confounded by cultural expectations, including sharing. We compared self-reported tobacco consumption with community-level estimates in Arnhem Land (Northern Territory). In a cross-sectional survey in three communities (population 2319 Indigenous residents, aged ≥16 years), 400 Indigenous residents were interviewed (206 men, 194 women). Eight community stores provided information about tobacco sold during the survey. To gauge the impact of 255 non-Indigenous residents on tobacco turnover, 10 were interviewed (five men, five women). Breath carbon monoxide levels confirmed self-reported smoking. Self-reported number of cigarettes smoked per day was compared with daily tobacco consumption per user estimated using amounts of tobacco sold during 12 months before the survey (2007-2008). 'Lighter smokers' (Indigenous study participants, 305 (76%) used tobacco; four chewed tobacco. Of 301 Indigenous smokers, 177 (58%) provided self-reported consumption information; a median of 11-11.5 cigarettes per day in men and 5.5-10 cigarettes per day in women. Men were three times (odds ratio=2.9) more likely to be 'heavier smokers'. Store turnover data indicated that Indigenous tobacco users consumed the equivalent of 9.2-13.1 cigarettes per day; very similar to self-reported levels. Sixty per cent (=6/10) of non-Indigenous residents interviewed were smokers, but with little impact on tobacco turnover overall (2-6%). Smoking levels reported by Indigenous Australians in this study, when sharing tobacco was considered, closely reflected quantities of tobacco sold in community stores. © 2010 Australasian Professional Society on Alcohol and other Drugs.

  17. Optimization algorithms intended for self-tuning feedwater heater model

    International Nuclear Information System (INIS)

    Czop, P; Barszcz, T; Bednarz, J

    2013-01-01

    This work presents a self-tuning feedwater heater model. This work continues the work on first-principle gray-box methodology applied to diagnostics and condition assessment of power plant components. The objective of this work is to review and benchmark the optimization algorithms regarding the time required to achieve the best model fit to operational power plant data. The paper recommends the most effective algorithm to be used in the model adjustment process.

  18. [Effects of community health promotion project for garlic cultivating farmers based on self-efficacy theory and community capacity building framework].

    Science.gov (United States)

    Kim, Hyang-Sook; Gu, Mee Ock

    2011-02-01

    This study was conducted to test the effects of a community health promotion project for farmers cultivating garlic. Bandura's self-efficacy theory (1986) and Chaskin's community capacity framework (2001) were used as the theoretical framework. A nonequivalent control group pretest-posttest design was used. Study participants were 72 garlic farmers (intervention: 36, control: 36). The community health promotion project consisted of health promotion program and community capacity building strategies and was provided for 12 weeks (8 during farming off-season and 4 during farming season). Data were collected between February 23 and May 31, 2009 and were analyzed using chi-square test, Fisher's exact test, t-test, and repeated measure ANOVA using SPSS/WIN 12.0. For the experimental group, significant improvement was found for self-efficacy, farming related health behavior, physical fitness (muscle strength, muscle endurance, upper body flexibility, lower body flexibility, cardiovascular endurance, balance, agility), farmer's syndrome, and health related quality of life as compared to the control group. The findings of the study indicate that the community health promotion project for garlic farmers is effective and can be recommended as a nursing intervention for health promotion of garlic cultivating farmers.

  19. Effectiveness of Training Self-encauragement on the Resiliency and Optimism the Mothers of Children with Mental Retardation

    Directory of Open Access Journals (Sweden)

    A Afkhami Aqda

    2016-07-01

    Full Text Available Introduction: a retarded child is considered as a perishing pressure on the parents, hence, teaching these mothers is very important. One of the useful tasks to do for this, is teaching self-encouragement. The aim of the present study was to investigate the effectiveness of self-encouragement on resilience and optimism of mothers with mental retardation. Methods: The method was semi-experimental, pretest-posttest with a control group. The sample group included 24 mothers from Yazd city in 1393-94 with mentally retarded children volunteering (non-randomly for the study and finally divided into control and experimental groups (fifteen people each. The resilience and optimism of the participants were assessed using CD-RISK Connor-Davidson’s resilience questionnaire and life orientation test LOT, respectively LOT and the experiment group was instructed the self-encouragement program for 1 sessions. Results: Covariance analysis MANCOVA, ANCOVA in SPSS (ver. 22 of the data showed that the educational sessions had significant effect on resilience and optimism of the experimental group (p<0/05. Conclusion: Accordingly, it can be concluded that teaching self-encouragement can lead to more resilience and optimism.

  20. A Genetic Algorithms-based Approach for Optimized Self-protection in a Pervasive Service Middleware

    DEFF Research Database (Denmark)

    Zhang, Weishan; Ingstrup, Mads; Hansen, Klaus Marius

    2009-01-01

    With increasingly complex and heterogeneous systems in pervasive service computing, it becomes more and more important to provide self-protected services to end users. In order to achieve self-protection, the corresponding security should be provided in an optimized manner considering...... the constraints of heterogeneous devices and networks. In this paper, we present a Genetic Algorithms-based approach for obtaining optimized security configurations at run time, supported by a set of security OWL ontologies and an event-driven framework. This approach has been realized as a prototype for self-protection...... in the Hydra middleware, and is integrated with a framework for enforcing the computed solution at run time using security obligations. The experiments with the prototype on configuring security strategies for a pervasive service middleware show that this approach has acceptable performance, and could be used...

  1. Sub-Riemannian geometry and optimal transport

    CERN Document Server

    Rifford, Ludovic

    2014-01-01

    The book provides an introduction to sub-Riemannian geometry and optimal transport and presents some of the recent progress in these two fields. The text is completely self-contained: the linear discussion, containing all the proofs of the stated results, leads the reader step by step from the notion of distribution at the very beginning to the existence of optimal transport maps for Lipschitz sub-Riemannian structure. The combination of geometry presented from an analytic point of view and of optimal transport, makes the book interesting for a very large community. This set of notes grew from a series of lectures given by the author during a CIMPA school in Beirut, Lebanon.

  2. Integrative and Deep Learning through a Learning Community: A Process View of Self

    Science.gov (United States)

    Mahoney, Sandra; Schamber, Jon

    2011-01-01

    This study investigated deep learning produced in a community of general education courses. Student speeches on liberal education were analyzed for discovering a grounded theory of ideas about self. The study found that learning communities cultivate deep, integrative learning that makes the value of a liberal education relevant to students.…

  3. Stabilization of business cycles of finance agents using nonlinear optimal control

    Science.gov (United States)

    Rigatos, G.; Siano, P.; Ghosh, T.; Sarno, D.

    2017-11-01

    Stabilization of the business cycles of interconnected finance agents is performed with the use of a new nonlinear optimal control method. First, the dynamics of the interacting finance agents and of the associated business cycles is described by a modeled of coupled nonlinear oscillators. Next, this dynamic model undergoes approximate linearization round a temporary operating point which is defined by the present value of the system's state vector and the last value of the control inputs vector that was exerted on it. The linearization procedure is based on Taylor series expansion of the dynamic model and on the computation of Jacobian matrices. The modelling error, which is due to the truncation of higher-order terms in the Taylor series expansion is considered as a disturbance which is compensated by the robustness of the control loop. Next, for the linearized model of the interacting finance agents, an H-infinity feedback controller is designed. The computation of the feedback control gain requires the solution of an algebraic Riccati equation at each iteration of the control algorithm. Through Lyapunov stability analysis it is proven that the control scheme satisfies an H-infinity tracking performance criterion, which signifies elevated robustness against modelling uncertainty and external perturbations. Moreover, under moderate conditions the global asymptotic stability features of the control loop are proven.

  4. Self-consistent approach for neutral community models with speciation

    Science.gov (United States)

    Haegeman, Bart; Etienne, Rampal S.

    2010-03-01

    Hubbell’s neutral model provides a rich theoretical framework to study ecological communities. By incorporating both ecological and evolutionary time scales, it allows us to investigate how communities are shaped by speciation processes. The speciation model in the basic neutral model is particularly simple, describing speciation as a point-mutation event in a birth of a single individual. The stationary species abundance distribution of the basic model, which can be solved exactly, fits empirical data of distributions of species’ abundances surprisingly well. More realistic speciation models have been proposed such as the random-fission model in which new species appear by splitting up existing species. However, no analytical solution is available for these models, impeding quantitative comparison with data. Here, we present a self-consistent approximation method for neutral community models with various speciation modes, including random fission. We derive explicit formulas for the stationary species abundance distribution, which agree very well with simulations. We expect that our approximation method will be useful to study other speciation processes in neutral community models as well.

  5. Motivation and Self-Regulation in Community College Transfer Students at a Four-Year Online University

    Science.gov (United States)

    List, Alexandra; Nadasen, Denise

    2017-01-01

    Motivation and self-regulation were examined in a sample of community college transfer students enrolled in a 4-year, online university. The relation between motivation and self-regulation and students' performance was examined, as was the association between these learner characteristics (i.e., motivation and self-regulation) and sociodemographic…

  6. The relationships between sense of belonging to the gay community, body image dissatisfaction, and self-esteem among Australian gay men.

    Science.gov (United States)

    Kousari-Rad, Pantea; McLaren, Suzanne

    2013-01-01

    Body image dissatisfaction has been linked to belonging to the gay community and poor self-esteem among gay men. This study was designed to explore the applicability of a moderation model and a mediation model in explaining the relations between sense of belonging to the gay community, body image dissatisfaction and self-esteem among 90 self-identified Australian gay men. Participants completed the psychological subscale of the Sense of Belonging Instrument, the Body Satisfaction Scale, and the Rosenberg Self-Esteem Scale. Results supported the moderation model; the relation between body image dissatisfaction and self-esteem was found to be statistically significant only at average and high levels of belonging to the gay community. The mediation model was also supported; body image dissatisfaction partially mediated the sense of belonging-self-esteem relation. Educating gay men and health professionals about the possible negative outcomes of "belonging" to an appearance-oriented community is important.

  7. Shape optimization of self-avoiding curves

    Science.gov (United States)

    Walker, Shawn W.

    2016-04-01

    This paper presents a softened notion of proximity (or self-avoidance) for curves. We then derive a sensitivity result, based on shape differential calculus, for the proximity. This is combined with a gradient-based optimization approach to compute three-dimensional, parameterized curves that minimize the sum of an elastic (bending) energy and a proximity energy that maintains self-avoidance by a penalization technique. Minimizers are computed by a sequential-quadratic-programming (SQP) method where the bending energy and proximity energy are approximated by a finite element method. We then apply this method to two problems. First, we simulate adsorbed polymer strands that are constrained to be bound to a surface and be (locally) inextensible. This is a basic model of semi-flexible polymers adsorbed onto a surface (a current topic in material science). Several examples of minimizing curve shapes on a variety of surfaces are shown. An advantage of the method is that it can be much faster than using molecular dynamics for simulating polymer strands on surfaces. Second, we apply our proximity penalization to the computation of ideal knots. We present a heuristic scheme, utilizing the SQP method above, for minimizing rope-length and apply it in the case of the trefoil knot. Applications of this method could be for generating good initial guesses to a more accurate (but expensive) knot-tightening algorithm.

  8. Prevalence of drug-related problems in self-medication in Danish community pharmacies

    Directory of Open Access Journals (Sweden)

    Bente Frøkjær

    2012-01-01

    Full Text Available Background: Drug-related problems are known to be a major problem associated with pharmacotherapy. A broad range of studies, mainly in the area of prescription-only medicines, supports this fact. Only a few studies have evaluated drug-related problems with over-the-counter medicine and the role of community pharmacies in this. Purpose: To quantify drug-related problems in self-medication (use of over-the-counter medicine identified by community pharmacies in Denmark and to document the interventions by pharmacy staff in relation to the identified drug-related problems. Method: A descriptive study mapping drug-related problems in self-medication registered at the counter at a selected number of Danish community pharmacies. Results: Data for 3,868 consecutive customers with requests for over-the-counter (OTC medicines were registered at 39 community pharmacies. The pharmacies registered a total number of 4,324 OTC medicines requests, illustrating that a customer requested 1.1 OTC medicines on average. Drug-related problems (DRPs were identified for 813 customers, equivalent to DRPs for 21.0 % of all customers, presenting symptoms or requesting OTC medicines, and for 20 % of all over-the-counter medicines requests. 1,239 DRPs were registered, corresponding to an average of 1.5 DRPs per customer requesting OTC medicines. Community pharmacies estimated that they solved or partly solved 76.2 % of the detected DRPs; 73 % were solved without involving a general practitioner. Conclusions: DRPs were identified for 21.0 % of the pharmacy customers presenting a symptom or asking for an OTC medicine. The community pharmacy counselled the customers with DRPs more thoroughly than other customers by giving 2.4 pieces of professional advice, compared to an average of 2.1 to customers in general. It is not possible to determine the magnitude of the safety risk involved. Based on the most frequent categories of DRPs, there were risks of insufficient effect

  9. Prevalence of drug-related problems in self-medication in Danish community pharmacies

    Directory of Open Access Journals (Sweden)

    Charlotte Rossing

    2012-01-01

    Full Text Available Background: Drug-related problems are known to be a major problem associated with pharmacotherapy. A broad range of studies, mainly in the area of prescription-only medicines, supports this fact. Only a few studies have evaluated drug-related problems with over-the-counter medicine and the role of community pharmacies in this.Purpose: To quantify drug-related problems in self-medication (use of over-the-counter medicine identified by community pharmacies in Denmark and to document the interventions by pharmacy staff in relation to the identified drug-related problems.Method: A descriptive study mapping drug-related problems in self-medication registered at the counter at a selected number of Danish community pharmacies.Results: Data for 3,868 consecutive customers with requests for over-the-counter (OTC medicines were registered at 39 community pharmacies. The pharmacies registered a total number of 4,324 OTC medicines requests, illustrating that a customer requested 1.1 OTC medicines on average. Drug-related problems (DRPs were identified for 813 customers, equivalent to DRPs for 21.0 % of all customers, presenting symptoms or requesting OTC medicines, and for 20 % of all over-the-counter medicines requests. 1,239 DRPs were registered, corresponding to an average of 1.5 DRPs per customer requesting OTC medicines.Community pharmacies estimated that they solved or partly solved 76.2 % of the detected DRPs; 73 % were solved without involving a general practitioner.Conclusions: DRPs were identified for 21.0 % of the pharmacy customers presenting a symptom or asking for an OTC medicine. The community pharmacy counselled the customers with DRPs more thoroughly than other customers by giving 2.4 pieces of professional advice, compared to an average of 2.1 to customers in general. It is not possible to determine the magnitude of the safety risk involved. Based on the most frequent categories of DRPs, there were risks of insufficient effect, unintended

  10. Enhancing Self-Efficacy in Elementary Science Teaching With Professional Learning Communities

    Science.gov (United States)

    Mintzes, Joel J.; Marcum, Bev; Messerschmidt-Yates, Christl; Mark, Andrew

    2013-11-01

    Emerging from Bandura's Social Learning Theory, this study of in-service elementary school teachers examined the effects of sustained Professional Learning Communities (PLCs) on self-efficacy in science teaching. Based on mixed research methods, and a non-equivalent control group experimental design, the investigation explored changes in personal self-efficacy and outcome expectancy among teachers engaged in PLCs that featured Demonstration Laboratories, Lesson Study, and annual Summer Institutes. Significant changes favoring the experimental group were found on all quantitative measures of self-efficacy. Structured clinical interviews revealed that observed changes were largely attributable to a wide range of direct (mastery) and vicarious experiences, as well as emotional reinforcement and social persuasion.

  11. Optimization of self-consumption and techno-economic analysis of PV-battery systems in commercial applications

    International Nuclear Information System (INIS)

    Merei, Ghada; Moshövel, Janina; Magnor, Dirk; Sauer, Dirk Uwe

    2016-01-01

    Highlights: • Optimization of self-consumption and the degree of self-sufficiency in commercial applications. • Technical and economic analyses for a PV-battery system. • Sensitivity analysis considering different sizes and prices of PV and battery systems. • Investigation of batteries to increase self-consumption today is not economic in the considered applications. - Abstract: Increasing costs of electricity supply from the local grid, the decreasing photovoltaic (PV) technology costs and the decreasing PV feed-in-tariff according to the current German Renewable Energy Sources Act (EEG) will in the future raise the monetary incentives to increase the self-consumption of PV energy. This is of great interest in commercial buildings as there mostly is sufficient place to install high capacities of photovoltaic panels on their own roofs. Furthermore, the electricity purchase price from the local grid for commercial consumers nowadays is about 20 €ct/kW h, which is higher than the cost of generation of electricity from solar panels (about 8–12 €ct/kW h). Additionally, the load profiles in commercial applications have a high correlation with the generated solar energy. Hence, there is a great opportunity for economic savings. This paper presents optimization results with respect to self-consumption and degree of self-sufficiency for a supermarket in Aachen, Germany. The optimization is achieved using real measurement data of load profile and solar radiation. Besides, techno-economic analyses and sensitivity analyses have been carried out to demonstrate the influence of different PV system sizes, PV system costs and interest rates. Moreover, to raise self-consumption different battery sizes with different battery system costs have been investigated and analysed for 2015 and 2025 scenarios as well. The results show that the installation of a PV system can reduce the electricity costs through self-consumption of self-generated PV energy. Also, applying

  12. Self-regulated Learning in a Hybrid Science Course at a Community College

    Science.gov (United States)

    Manuelito, Shannon Joy

    Community college students are attracted to courses with alternative delivery formats such as hybrid courses because the more flexible delivery associated with such courses provides convenience for busy students. In a hybrid course, face-to-face, structured seat time is exchanged for online components. In such courses, students take more responsibility for their learning because they assume additional responsibility for learning more of the course material on their own. Thus, self-regulated learning (SRL) behaviors have the potential to be useful for students to successfully navigate hybrid courses because the online components require exercise of more personal control over the autonomous learning situations inherent in hybrid courses. Self-regulated learning theory includes three components: metacognition, motivation, and behavioral actions. In the current study, this theoretical framework is used to examine how inducing self-regulated learning activities among students taking a hybrid course influence performance in a community college science course. The intervention for this action research study consisted of a suite of activities that engage students in self-regulated learning behaviors to foster student performance. The specific SRL activities included predicting grades, reflections on coursework and study efforts in course preparation logs, explanation of SRL procedures in response to a vignette, photo ethnography work on their personal use of SRL approaches, and a personalized study plan. A mixed method approach was employed to gather evidence for the study. Results indicate that community college students use a variety of self-regulated learning strategies to support their learning of course material. Further, engaging community college students in learning reflection activities appears to afford some students with opportunities to refine their SRL skills and influence their learning. The discussion focuses on integrating the quantitative and qualitative

  13. An architect’s investigation into the self-reliance of a Sub-Saharan African community

    NARCIS (Netherlands)

    Michiel Smits

    2014-01-01

    This study investigates how externally initiated development projects and the role of the architect may influence the self-reliance of a local community. The development aid for rural communities aims to improve the living quality, but often does not persist in the long run.

  14. Influence of Precollege Experience on Self-Concept among Community College Students in Science, Mathematics, and Engineering

    Science.gov (United States)

    Starobin, Soko S.; Laanan, Frankie Santos

    Female and minority students have historically been underrepresented in the field of science, mathematics, and engineering at colleges and universities. Although a plethora of research has focused on students enrolled in 4-year colleges or universities, limited research addresses the factors that influence gender differences in community college students in science, mathematics, and engineering. Using a target population of 1,599 aspirants in science, mathematics, and engineering majors in public community colleges, this study investigates the determinants of self-concept by examining a hypothetical structural model. The findings suggest that background characteristics, high school academic performance, and attitude toward science have unique contributions to the development of self-concept among female community college students. The results add to the literature by providing new theoretical constructs and the variables that predict students' self-concept.

  15. L2-stability of the Vlasov-Maxwell-Boltzmann system near global Maxwellians

    International Nuclear Information System (INIS)

    Ha, Seung-Yeal; Xiao, Qinghua; Xiong, Linjie; Zhao, Huijiang

    2013-01-01

    We present a L 2 -stability theory of the Vlasov-Maxwell-Boltzmann system for the two-species collisional plasma. We show that in a perturbative regime of a global Maxwellian, the L 2 -distance between two strong solutions can be controlled by that between initial data in a Lipschitz manner. Our stability result extends earlier results [Ha, S.-Y. and Xiao, Q.-H., “A revisiting to the L 2 -stability theory of the Boltzmann equation near global Maxwellians,” (submitted) and Ha, S.-Y., Yang, X.-F., and Yun, S.-B., “L 2 stability theory of the Boltzmann equation near a global Maxwellian,” Arch. Ration. Mech. Anal. 197, 657–688 (2010)] on the L 2 -stability of the Boltzmann equation to the Boltzmann equation coupled with self-consistent external forces. As a direct application of our stability result, we show that classical solutions in Duan et al. [“Optimal large-time behavior of the Vlasov-Maxwell-Boltzmann system in the whole space,” Commun. Pure Appl. Math. 24, 1497–1546 (2011)] and Guo [“The Vlasov-Maxwell-Boltzmann system near Maxwellians,” Invent. Math. 153(3), 593–630 (2003)] satisfy a uniform L 2 -stability estimate. This is the first result on the L 2 -stability of the Boltzmann equation coupled with self-consistent field equations in three dimensions

  16. Self-adaptive global best harmony search algorithm applied to reactor core fuel management optimization

    International Nuclear Information System (INIS)

    Poursalehi, N.; Zolfaghari, A.; Minuchehr, A.; Valavi, K.

    2013-01-01

    Highlights: • SGHS enhanced the convergence rate of LPO using some improvements in comparison to basic HS and GHS. • SGHS optimization algorithm obtained averagely better fitness relative to basic HS and GHS algorithms. • Upshot of the SGHS implementation in the LPO reveals its flexibility, efficiency and reliability. - Abstract: The aim of this work is to apply the new developed optimization algorithm, Self-adaptive Global best Harmony Search (SGHS), for PWRs fuel management optimization. SGHS algorithm has some modifications in comparison with basic Harmony Search (HS) and Global-best Harmony Search (GHS) algorithms such as dynamically change of parameters. For the demonstration of SGHS ability to find an optimal configuration of fuel assemblies, basic Harmony Search (HS) and Global-best Harmony Search (GHS) algorithms also have been developed and investigated. For this purpose, Self-adaptive Global best Harmony Search Nodal Expansion package (SGHSNE) has been developed implementing HS, GHS and SGHS optimization algorithms for the fuel management operation of nuclear reactor cores. This package uses developed average current nodal expansion code which solves the multi group diffusion equation by employment of first and second orders of Nodal Expansion Method (NEM) for two dimensional, hexagonal and rectangular geometries, respectively, by one node per a FA. Loading pattern optimization was performed using SGHSNE package for some test cases to present the SGHS algorithm capability in converging to near optimal loading pattern. Results indicate that the convergence rate and reliability of the SGHS method are quite promising and practically, SGHS improves the quality of loading pattern optimization results relative to HS and GHS algorithms. As a result, it has the potential to be used in the other nuclear engineering optimization problems

  17. Optimal Stabilization of Social Welfare under Small Variation of Operating Condition with Bifurcation Analysis

    Science.gov (United States)

    Chanda, Sandip; De, Abhinandan

    2016-12-01

    A social welfare optimization technique has been proposed in this paper with a developed state space based model and bifurcation analysis to offer substantial stability margin even in most inadvertent states of power system networks. The restoration of the power market dynamic price equilibrium has been negotiated in this paper, by forming Jacobian of the sensitivity matrix to regulate the state variables for the standardization of the quality of solution in worst possible contingencies of the network and even with co-option of intermittent renewable energy sources. The model has been tested in IEEE 30 bus system and illustrious particle swarm optimization has assisted the fusion of the proposed model and methodology.

  18. Stability Development of Immediately Loaded Hybrid Self-Tapping Implants Inserted in the Posterior Maxilla: 1-Year Results of a Randomized Controlled Trial.

    Science.gov (United States)

    Todorovic, Vladimir S; Vasovic, Miroslav; Beetge, Mia-Michaela; van Zyl, Andre W; Kokovic, Vladimir

    2017-02-01

    The objective of the present study was to elucidate stability development of immediately loaded hybrid self-tapping implants inserted in the posterior maxilla. Forty-eight hybrid self-tapping implants with a chemically modified surface (∅4.1; length: 8 mm) were inserted bilaterally in the maxillary first and second premolar and first molar sites of 8 patients. In each patient, both sides of the maxilla were assigned randomly to either immediate (IL) or early (EL) loading group. Implant stability was evaluated by means of resonance frequency analysis immediately after implant placement and after 1, 2, 3, 4, 5, 6, 12, 26, and 52 weeks. High values of primary stability were found in both groups (71.91 ± 6.52 implant stability quotient [ISQ] in IL group; 73.87 ± 6.5 ISQ in EL group), with significant differences between the groups at the different time points. Initial decrease in stability was observed between the first and fifth weeks in the IL group and between the first and third weeks for the EL group. In the IL group 1 implant was removed after 3 weeks due to lack of stability. Early results of this study showed the ability of hybrid self-tapping dental implants with a chemically modified surface to achieve sufficient primary stability and to maintain high values of secondary implant stability in bone type 3 and 4, even when loaded immediately. Minimal alterations in stability were observed for both investigated groups, but the EL group showed faster recovery after an initial drop in stability.

  19. A tighter bound for the self-stabilization time in Hermanʼs algorithm

    DEFF Research Database (Denmark)

    Feng, Yuan; Zhang, Lijun

    2013-01-01

    We study the expected self-stabilization time of Hermanʼs algorithm. For N processors the lower bound is 427N2 (0.148N2), and an upper bound of 0.64N2 is presented in Kiefer et al. (2011) [4]. In this paper we give a tighter upper bound 0.521N2. © 2013 Published by Elsevier B.V....

  20. Optimal Growth in Hypersonic Boundary Layers

    Science.gov (United States)

    Paredes, Pedro; Choudhari, Meelan M.; Li, Fei; Chang, Chau-Lyan

    2016-01-01

    The linear form of the parabolized linear stability equations is used in a variational approach to extend the previous body of results for the optimal, nonmodal disturbance growth in boundary-layer flows. This paper investigates the optimal growth characteristics in the hypersonic Mach number regime without any high-enthalpy effects. The influence of wall cooling is studied, with particular emphasis on the role of the initial disturbance location and the value of the spanwise wave number that leads to the maximum energy growth up to a specified location. Unlike previous predictions that used a basic state obtained from a self-similar solution to the boundary-layer equations, mean flow solutions based on the full Navier-Stokes equations are used in select cases to help account for the viscous- inviscid interaction near the leading edge of the plate and for the weak shock wave emanating from that region. Using the full Navier-Stokes mean flow is shown to result in further reduction with Mach number in the magnitude of optimal growth relative to the predictions based on the self-similar approximation to the base flow.

  1. Nitrogen availability alters macrofungal basidiomycete Blackwell Publishing, Ltd. community structure in optimally fertilized loblolly pine forests

    Science.gov (United States)

    Ivan P. Edwards; Jennifer L. Cripliver; Andrew R. Gillespie; Kurt H. Johnsen; M. Scholler; Ronald F. Turco

    2004-01-01

    We investigated the effect of an optimal nutrition strategy designed to maximize loblolly pine (Pinus taeda) growth on the rank abundance structure and diversity of associated basidiomycete communities.We conducted both small- and large-scale below-ground surveys 10 years after the initiation of optimal...

  2. Optimal design of power system stabilizer for power systems including doubly fed induction generator wind turbines

    International Nuclear Information System (INIS)

    Derafshian, Mehdi; Amjady, Nima

    2015-01-01

    This paper presents an evolutionary algorithm-based approach for optimal design of power system stabilizer (PSS) for multi-machine power systems that include doubly fed induction generator wind turbines. The proposed evolutionary algorithm is an improved particle swarm optimization named chaotic particle swarm optimization with passive congregation (CPSO-PC) applied for finding the optimal settings of PSS parameters. Two different eigenvalue-based objectives are combined as the objective function for the optimization problem of tuning PSS parameters. The first objective function comprises the damping factor of lightly damped electro-mechanical modes and the second one includes the damping ratio of these modes. The effectiveness of the proposed method to design PSS for the power systems including DFIG (Doubly Fed Induction Generator) is extensively demonstrated through eigenvalue analysis and time-domain simulations and also by comparing its simulation results with the results of other heuristic optimization approaches. - Highlights: • A new optimization model for design of PSS in power systems including DFIG is proposed. • A detailed and realistic modeling of DFIG is presented. • A new evolutionary algorithm is suggested for solving the optimization problem of designing PSS

  3. Study and Optimization of Self-Assembled Polymeric Multilayer Structures with Neutral Red for pH Sensing Applications

    Directory of Open Access Journals (Sweden)

    Javier Goicoechea

    2008-01-01

    Full Text Available The characterization of nanostructured thin films is critical in the design and fabrication of optical sensors. Particularly, this work is a detailed study of the properties of layer-by-layer electrostatic self-assembled multilayer (LbL structures fabricated using poly(allylamine hydrochloride (PAH and Neutral Red (NR as cations, and poly(acrylic acid (PAA as polyanion. These LbL films, due to the colorimetric properties of the NR, are suitable for sensor applications such as pH sensing in the physiological range. In the (PAH+NR/PAA LbL structure, it has been observed a very important influence of the pH of the solutions in the properties of the resultant films. Different techniques such as spectroscopy and atomic force microscopy (AFM are combined to characterize the films, and the results are analyzed showing coherence with previous works. The LbL structure is finally optimized and dramatically improved nanostructured films were fabricated, showing good sensing properties, short response times, and good stability.

  4. Compositional Stability of the Bacterial Community in a Climate-Sensitive Sub-Arctic Peatland.

    Science.gov (United States)

    Weedon, James T; Kowalchuk, George A; Aerts, Rien; Freriks, Stef; Röling, Wilfred F M; van Bodegom, Peter M

    2017-01-01

    The climate sensitivity of microbe-mediated soil processes such as carbon and nitrogen cycling offers an interesting case for evaluating the corresponding sensitivity of microbial community composition to environmental change. Better understanding of the degree of linkage between functional and compositional stability would contribute to ongoing efforts to build mechanistic models aiming at predicting rates of microbe-mediated processes. We used an amplicon sequencing approach to test if previously observed large effects of experimental soil warming on C and N cycle fluxes (50-100% increases) in a sub-arctic Sphagnum peatland were reflected in changes in the composition of the soil bacterial community. We found that treatments that previously induced changes to fluxes did not associate with changes in the phylogenetic composition of the soil bacterial community. For both DNA- and RNA-based analyses, variation in bacterial communities could be explained by the hierarchy: spatial variation (12-15% of variance explained) > temporal variation (7-11%) > climate treatment (4-9%). We conclude that the bacterial community in this environment is stable under changing conditions, despite the previously observed sensitivity of process rates-evidence that microbe-mediated soil processes can alter without concomitant changes in bacterial communities. We propose that progress in linking soil microbial communities to ecosystem processes can be advanced by further investigating the relative importance of community composition effects versus physico-chemical factors in controlling biogeochemical process rates in different contexts.

  5. Integrating plant-microbe interactions to understand soil C stabilization with the MIcrobial-MIneral Carbon Stabilization model (MIMICS)

    Science.gov (United States)

    Grandy, Stuart; Wieder, Will; Kallenbach, Cynthia; Tiemann, Lisa

    2014-05-01

    that current ideas about plant-microbe-SOM relationships are unraveling. If so, our reconsideration of the mechanisms stabilizing SOM will also challenge long-held views about how to optimize plant community management to increase SOM.

  6. Optimism and spontaneous self-affirmation are associated with lower likelihood of cognitive impairment and greater positive affect among cancer survivors

    Science.gov (United States)

    Taber, Jennifer M.; Klein, William M. P.; Ferrer, Rebecca A.; Kent, Erin E.; Harris, Peter R.

    2016-01-01

    Background Optimism and self-affirmation promote adaptive coping, goal achievement, and better health. Purpose To examine the associations of optimism and spontaneous self-affirmation (SSA) with physical, mental, and cognitive health and information seeking among cancer survivors. Methods Cancer survivors (n=326) completed the Health Information National Trends Survey 2013, a national survey of U.S. adults. Participants reported optimism, SSA, cognitive and physical impairment, affect, health status, and information seeking. Results Participants higher in optimism reported better health on nearly all indices examined, even when controlling for SSA. Participants higher in SSA reported lower likelihood of cognitive impairment, greater happiness and hopefulness, and greater likelihood of cancer information seeking. SSA remained significantly associated with greater hopefulness and cancer information seeking when controlling for optimism. Conclusions Optimism and SSA may be associated with beneficial health-related outcomes among cancer survivors. Given the demonstrated malleability of self-affirmation, these findings represent important avenues for future research. PMID:26497697

  7. Optimism and Spontaneous Self-affirmation are Associated with Lower Likelihood of Cognitive Impairment and Greater Positive Affect among Cancer Survivors.

    Science.gov (United States)

    Taber, Jennifer M; Klein, William M P; Ferrer, Rebecca A; Kent, Erin E; Harris, Peter R

    2016-04-01

    Optimism and self-affirmation promote adaptive coping, goal achievement, and better health. The aim of this study is to examine the associations of optimism and spontaneous self-affirmation (SSA) with physical, mental, and cognitive health and information seeking among cancer survivors. Cancer survivors (n = 326) completed the Health Information National Trends Survey 2013, a national survey of US adults. Participants reported optimism, SSA, cognitive and physical impairment, affect, health status, and information seeking. Participants higher in optimism reported better health on nearly all indices examined, even when controlling for SSA. Participants higher in SSA reported lower likelihood of cognitive impairment, greater happiness and hopefulness, and greater likelihood of cancer information seeking. SSA remained significantly associated with greater hopefulness and cancer information seeking when controlling for optimism. Optimism and SSA may be associated with beneficial health-related outcomes among cancer survivors. Given the demonstrated malleability of self-affirmation, these findings represent important avenues for future research.

  8. Looking Similar Promotes Group Stability in a Game-Based Virtual Community.

    Science.gov (United States)

    Lortie, Catherine L; Guitton, Matthieu J

    2012-08-01

    Online support groups are popular Web-based resources that provide tailored information and peer support through virtual communities and fulfill the users' needs for empowerment and belonging. However, the therapeutic potential of online support groups is at present limited by the lack of systematic research on the cognitive mechanisms underlying social group cohesion in virtual communities. We might increase the benefits of participation in online support groups if we gain more insight into the factors that promote long-term commitment to peer support. One approach to foster the therapeutic potential of online support groups could be to increase social selection based on visual similarity. We performed a case study using the popular virtual setting of "World of Warcraft" (Blizzard Entertainment, Irvine, CA). We monitored the social dynamics of a virtual community composed of avatars whose appearance was identical during a period of 3 months, biweekly, for a total of 24 measures. We observed that this homogeneous community displayed a very high level of group stability over time in terms of the total number of members, the number of members that stayed the same, and the number of arrivals and departures, despite the fact that belonging to a heterogeneous group typically favors the success of the group with respect to game progression. Our results confirm that appearance can trigger social selection in online virtual communities. Displaying a similar appearance could be one way to strengthen social bonds among peers who share various health and well-being issues. Thus, the therapeutic potential of online support groups could be promoted through visual cohesion.

  9. A systematic review of the efficacy of self-management programs for increasing physical activity in community-dwelling adults with acquired brain injury (ABI).

    Science.gov (United States)

    Jones, Taryn M; Dean, Catherine M; Hush, Julia M; Dear, Blake F; Titov, Nickolai

    2015-04-19

    Individuals living with acquired brain injury, typically caused by stroke or trauma, are far less likely to achieve recommended levels of physical activity for optimal health and well-being. With a growing number of people living with chronic disease and disability globally, self-management programs are seen as integral to the management of these conditions and the prevention of secondary health conditions. However, to date, there has been no systematic review of the literature examining the efficacy of self-management programs specifically on physical activity in individuals with acquired brain injury, whether delivered face-to-face or remotely. Therefore, the purpose of this review is to evaluate the efficacy of self-management programs in increasing physical activity levels in adults living in the community following acquired brain injury. The efficacy of remote versus face-to-face delivery was also examined. A systematic review of the literature was conducted. Electronic databases were searched. Two independent reviewers screened all studies for eligibility, assessed risk of bias, and extracted relevant data. Five studies met the inclusion criteria for this review. Studies were widely heterogeneous with respect to program content and delivery characteristics and outcomes, although all programs utilized behavioral change principles. Four of the five studies examined interventions in which physical activity was a component of a multifaceted intervention, where the depth to which physical activity specific content was covered, and the extent to which skills were taught and practiced, could not be clearly established. Three studies showed favorable physical activity outcomes following self-management interventions for stroke; however, risk of bias was high, and overall efficacy remains unclear. Although not used in isolation from face-to-face delivery, remote delivery via telephone was the predominant form of delivery in two studies with support for its inclusion

  10. Time and temperature dependent analytical stability of dry-collected Evalyn HPV self-sampling brush for cervical cancer screening

    DEFF Research Database (Denmark)

    Ejegod, Ditte Møller; Pedersen, Helle; Alzua, Garazi Peña

    2018-01-01

    As a new initiative, HPV self-sampling to non-attenders using the dry Evalyn self-sampling brush is offered in the Capital Region of Denmark. The use of a dry brush is largely uncharted territory in terms of analytical stability. In this study we aim to provide evidence on the analytical quality...

  11. Could a brief assessment of negative emotions and self-esteem identify adolescents at current and future risk of self-harm in the community? A prospective cohort analysis.

    Science.gov (United States)

    Phillips, Rhiannon; Spears, Melissa R; Montgomery, Alan A; Millings, Abigail; Sayal, Kapil; Stallard, Paul

    2013-06-22

    Self-harm is common in adolescents, but it is often unreported and undetected. Available screening tools typically ask directly about self-harm and suicidal ideation. Although in an ideal world, direct enquiry and open discussion around self-harm would be advocated, non-psychiatric professionals in community settings are often reluctant to ask about this directly and disclosure can be met with feeling of intense anxiety. Training non-specialist staff to directly ask about self-harm has limited effects suggesting that alternative approaches are required. This study investigated whether a targeted analysis of negative emotions and self-esteem could identify young adolescents at risk of self-harm in community settings. Data were collected as part of a clinical trial from young people in school years 8-11 (aged 12-16) at eight UK secondary schools (N = 4503 at baseline, N = 3263 in prospective analysis). The Short Mood and Feelings Questionnaire, Revised Child Anxiety and Depression Scale, Rosenberg Self-Esteem Scale, personal failure (Children's Automatic Thoughts Scale), and two items on self-harm were completed at baseline, 6 and 12 months. Following a process of Principal Components Analysis, item reduction, and logistic regression analysis, three internally reliable factors were identified from the original measures that were independently associated with current and future self-harm; personal failure (3 items), physical symptoms of depression/anxiety (6 items), positive self-esteem (5 items). The summed score of these 14 items had good accuracy in identifying current self-harm (AUC 0.87 girls, 0.81 boys) and at six months for girls (0.81), and fair accuracy at six months for boys (AUC 0.74) and 12 months for girls (AUC 0.77). A brief and targeted assessment of negative emotions and self-esteem, focusing on factors that are strongly associated with current and future self-harm, could potentially be used to help identify adolescents who are at risk in

  12. PoPMuSiC 2.1: a web server for the estimation of protein stability changes upon mutation and sequence optimality

    Directory of Open Access Journals (Sweden)

    Rooman Marianne

    2011-05-01

    Full Text Available Abstract Background The rational design of modified proteins with controlled stability is of extreme importance in a whole range of applications, notably in the biotechnological and environmental areas, where proteins are used for their catalytic or other functional activities. Future breakthroughs in medical research may also be expected from an improved understanding of the effect of naturally occurring disease-causing mutations on the molecular level. Results PoPMuSiC-2.1 is a web server that predicts the thermodynamic stability changes caused by single site mutations in proteins, using a linear combination of statistical potentials whose coefficients depend on the solvent accessibility of the mutated residue. PoPMuSiC presents good prediction performances (correlation coefficient of 0.8 between predicted and measured stability changes, in cross validation, after exclusion of 10% outliers. It is moreover very fast, allowing the prediction of the stability changes resulting from all possible mutations in a medium size protein in less than a minute. This unique functionality is user-friendly implemented in PoPMuSiC and is particularly easy to exploit. Another new functionality of our server concerns the estimation of the optimality of each amino acid in the sequence, with respect to the stability of the structure. It may be used to detect structural weaknesses, i.e. clusters of non-optimal residues, which represent particularly interesting sites for introducing targeted mutations. This sequence optimality data is also expected to have significant implications in the prediction and the analysis of particular structural or functional protein regions. To illustrate the interest of this new functionality, we apply it to a dataset of known catalytic sites, and show that a much larger than average concentration of structural weaknesses is detected, quantifying how these sites have been optimized for function rather than stability. Conclusion The

  13. Self-organization and stability of magnetosome chains—A simulation study

    Science.gov (United States)

    Faivre, Damien; Klumpp, Stefan

    2018-01-01

    Magnetotactic bacteria orient in magnetic fields with the help of their magnetosome chain, a linear structure of membrane enclosed magnetic nanoparticles (magnetosomes) anchored to a cytoskeletal filament. Here, we use simulations to study the assembly and the stability of magnetosome chains. We introduce a computational model describing the attachment of the magnetosomes to the filament and their magnetic interactions. We show that the filamentous backbone is crucial for the robust assembly of the magnetic particles into a linear chain, which in turn is key for the functionality of the chain in cellular orientation and magnetically directed swimming. In addition, we simulate the response to an external magnetic field that is rotated away from the axis of the filament, an experimental method used to probe the mechanical stability of the chain. The competition between alignment along the filament and alignment with the external fields leads to the rupture of a chain if the applied field exceeeds a threshold value. These observations are in agreement with previous experiments at the population level. Beyond that, our simulations provide a detailed picture of chain rupture at the single cell level, which is found to happen through two abrupt events, which both depend on the field strength and orientation. The re-formation of the chain structure after such rupture is found to be strongly sped up in the presence of a magnetic field parallel to the filament, an observation that may also be of interest for the design of self-healing materials. Our simulations underline the dynamic nature of the magnetosome chain. More generally, they show the rich complexity of self-assembly in systems with competing driving forces for alignment. PMID:29315342

  14. Effects of tooth root contact on the stability of orthodontic anchor screws in the maxilla: Comparison between self-drilling and self-tapping methods.

    Science.gov (United States)

    Iwai, Hiroaki; Motoyoshi, Mitsuru; Uchida, Yasuki; Matsuoka, Miho; Shimizu, Noriyoshi

    2015-04-01

    We evaluated the effects of screw placement angle on the frequency of root contact and the effects of root contact on screw stability, comparing self-drilling and self-tapping methods. In total, 80 patients with 142 screws (diameter, 1.6 mm; length, 8.0 mm) were included. Cone-beam computed tomography images were taken. Cortical bone thickness, interroot distance, shortest distance between the screw and adjacent tooth root, and screw placement angle were measured. The success rates of the screws were 91.5% for the self-drilling method and 94.4% for the self-tapping method (P >0.05). The self-drilling screws tended to contact the distal tooth roots in the right maxilla. In the self-drilling method, the failure rate was significantly higher in the root contact group than in the no-contact group (P tapping methods in the maxilla. Avoidance of tooth root contact may improve the success rate more in the self-drilling method than in the self-tapping method. Copyright © 2015 American Association of Orthodontists. Published by Elsevier Inc. All rights reserved.

  15. Equilibrium properties of simple metal thin films in the self-compressed stabilized jellium model.

    Science.gov (United States)

    Mahmoodi, T; Payami, M

    2009-07-01

    In this work, we have applied the self-compressed stabilized jellium model to predict the equilibrium properties of isolated thin Al, Na and Cs slabs. To make a direct correspondence to atomic slabs, we have considered only those L values that correspond to n-layered atomic slabs with 2≤n≤20, for surface indices (100), (110), and (111). The calculations are based on the density functional theory and self-consistent solution of the Kohn-Sham equations in the local density approximation. Our results show that firstly, the quantum size effects are significant for slabs with sizes smaller than or near to the Fermi wavelength of the valence electrons λ(F), and secondly, some slabs expand while others contract with respect to the bulk spacings. Based on the results, we propose a criterion for realization of significant quantum size effects that lead to expansion of some thin slabs. For more justification of the criterion, we have tested it on Li slabs for 2≤n≤6. We have compared our Al results with those obtained from using all-electron or pseudo-potential first-principles calculations. This comparison shows excellent agreements for Al(100) work functions, and qualitatively good agreements for the other work functions and surface energies. These agreements justify the way we have used the self-compressed stabilized jellium model for the correct description of the properties of simple metal slab systems. On the other hand, our results for the work functions and surface energies of large- n slabs are in good agreement with those obtained from applying the stabilized jellium model for semi-infinite systems. In addition, we have performed the slab calculations in the presence of surface corrugation for selected Al slabs and have shown that the results are worsened.

  16. Optimizing classroom instruction through self-paced learning prototype

    Directory of Open Access Journals (Sweden)

    Romiro Gordo Bautista

    2015-09-01

    Full Text Available This study investigated the learning impact of self-paced learning prototype in optimizing classroom instruction towards students’ learning in Chemistry. Two sections of 64 Laboratory High School students in Chemistry were used as subjects of the study. The Quasi-Experimental and Correlation Research Design was used in the study: a pre-test was conducted, scored and analyzed which served as the basis in determining the initial learning schema of the respondents. A questionnaire was adopted to find the learning motivation of the students in science. Using Pearson-r correlation, it was found out that there is a highly significant relationship between their internal drive and their academic performance. Moreover, a post-test was conducted after self-paced learning prototype was used in the development of select topics in their curricular plot. It was found out that the students who experienced the self-paced learning prototype performed better in their academic performance as evidenced by the difference of their mean post-test results. ANCOVA results on the post-test mean scores of the respondents were utilized in establishing the causal-effect of the learning prototype to the academic performance of the students in Chemistry. A highly significant effect on their academic performance (R-square value of 70.7% and significant interaction of the models to the experimental grouping and mental abilities of the respondents are concluded in the study.

  17. Validating the Factor Structure of the Self-Report Psychopathy Scale in a Community Sample

    Science.gov (United States)

    Mahmut, Mehmet K.; Menictas, Con; Stevenson, Richard J.; Homewood, Judi

    2011-01-01

    Currently, there is no standard self-report measure of psychopathy in community-dwelling samples that parallels the most commonly used measure of psychopathy in forensic and clinical samples, the Psychopathy Checklist. A promising instrument is the Self-Report Psychopathy scale (SRP), which was derived from the original version the Psychopathy…

  18. Sensitivity of system stability to model structure

    Science.gov (United States)

    Hosack, G.R.; Li, H.W.; Rossignol, P.A.

    2009-01-01

    A community is stable, and resilient, if the levels of all community variables can return to the original steady state following a perturbation. The stability properties of a community depend on its structure, which is the network of direct effects (interactions) among the variables within the community. These direct effects form feedback cycles (loops) that determine community stability. Although feedback cycles have an intuitive interpretation, identifying how they form the feedback properties of a particular community can be intractable. Furthermore, determining the role that any specific direct effect plays in the stability of a system is even more daunting. Such information, however, would identify important direct effects for targeted experimental and management manipulation even in complex communities for which quantitative information is lacking. We therefore provide a method that determines the sensitivity of community stability to model structure, and identifies the relative role of particular direct effects, indirect effects, and feedback cycles in determining stability. Structural sensitivities summarize the degree to which each direct effect contributes to stabilizing feedback or destabilizing feedback or both. Structural sensitivities prove useful in identifying ecologically important feedback cycles within the community structure and for detecting direct effects that have strong, or weak, influences on community stability. The approach may guide the development of management intervention and research design. We demonstrate its value with two theoretical models and two empirical examples of different levels of complexity. ?? 2009 Elsevier B.V. All rights reserved.

  19. Are the Economically Optimal Harvesting Strategies of Uneven-Aged Pinus nigra Stands Always Sustainable and Stabilizing?

    Directory of Open Access Journals (Sweden)

    Carmen Fullana-Belda

    2013-10-01

    Full Text Available Traditional uneven-aged forest management seeks a balance between equilibrium stand structure and economic profitability, which often leads to harvesting strategies concentrated in the larger diameter classes. The sustainability (i.e., population persistence over time and influence of such economically optimal strategies on the equilibrium position of a stand (given by the stable diameter distribution have not been sufficiently investigated in prior forest literature. This article therefore proposes a discrete optimal control model to analyze the sustainability and stability of the economically optimal harvesting strategies of uneven-aged Pinus nigra stands. For this model, we rely on an objective function that integrates financial data of harvesting operations with a projection matrix model that can describe the population dynamics. The model solution reveals the optimal management schedules for a wide variety of scenarios. To measure the distance between the stable diameter distribution and the economically optimal harvesting strategy distribution, the model uses Keyfitz’s delta, which returns high values for all the scenarios and, thus, suggests that those economically optimal harvesting strategies have an unstabilizing influence on the equilibrium positions. Moreover, the economically optimal harvesting strategies were unsustainable for all the scenarios.

  20. Modeling the self-affine structure and optimization conditions of city systems using the idea from fractals

    International Nuclear Information System (INIS)

    Chen Yanguang; Lin Jingyi

    2009-01-01

    This paper demonstrates self-affine fractal structure of city systems by means of theoretical and empirical analyses. A Cobb-Douglas-type function (C-D function) of city systems is derived from a general urban response equation, and the partial scaling exponent of the C-D function proved to be the fractal dimension reflecting the self-affine features of city systems. As a case, the self-affine fractal model is applied to the city of Zhengzhou, China, and the result is satisfying. A fractal parameter equation indicative of structural optimization conditions is then obtained from the C-D function. The equation suggests that priority should be given to the development of the urban element with a lower fractal dimension, or a higher partial scaling exponent, for utility maximization. Moreover, the fractal dimensions of different urban elements tend to become equivalent to each other in the long term. Accordingly, it is self-similar fractals rather than self-affine fractals that represent the optimal structure of city systems under ideal conditions.

  1. Activity and stability of a complex bacterial soil community under simulated Martian conditions

    Science.gov (United States)

    Hansen, Aviaja Anna; Merrison, Jonathan; Nørnberg, Per; Aagaard Lomstein, Bente; Finster, Kai

    2005-04-01

    A simulation experiment with a complex bacterial soil community in a Mars simulation chamber was performed to determine the effect of Martian conditions on community activity, stability and survival. At three different depths in the soil core short-term effects of Martian conditions with and without ultraviolet (UV) exposure corresponding to 8 Martian Sol were compared. Community metabolic activities and functional diversity, measured as glucose respiration and versatility in substrate utilization, respectively, decreased after UV exposure, whereas they remained unaffected by Martian conditions without UV exposure. In contrast, the numbers of culturable bacteria and the genetic diversity were unaffected by the simulated Martian conditions both with and without UV exposure. The genetic diversity of the soil community and of the colonies grown on agar plates were evaluated by denaturant gradient gel electrophoresis (DGGE) on DNA extracts. Desiccation of the soil prior to experimentation affected the functional diversity by decreasing the versatility in substrate utilization. The natural dominance of endospores and Gram-positive bacteria in the investigated Mars-analogue soil may explain the limited effect of the Mars incubations on the survival and community structure. Our results suggest that UV radiation and desiccation are major selecting factors on bacterial functional diversity in terrestrial bacterial communities incubated under simulated Martian conditions. Furthermore, these results suggest that forward contamination of Mars is a matter of great concern in future space missions.

  2. A Self-Adaptive Fuzzy c-Means Algorithm for Determining the Optimal Number of Clusters

    Science.gov (United States)

    Wang, Zhihao; Yi, Jing

    2016-01-01

    For the shortcoming of fuzzy c-means algorithm (FCM) needing to know the number of clusters in advance, this paper proposed a new self-adaptive method to determine the optimal number of clusters. Firstly, a density-based algorithm was put forward. The algorithm, according to the characteristics of the dataset, automatically determined the possible maximum number of clusters instead of using the empirical rule n and obtained the optimal initial cluster centroids, improving the limitation of FCM that randomly selected cluster centroids lead the convergence result to the local minimum. Secondly, this paper, by introducing a penalty function, proposed a new fuzzy clustering validity index based on fuzzy compactness and separation, which ensured that when the number of clusters verged on that of objects in the dataset, the value of clustering validity index did not monotonically decrease and was close to zero, so that the optimal number of clusters lost robustness and decision function. Then, based on these studies, a self-adaptive FCM algorithm was put forward to estimate the optimal number of clusters by the iterative trial-and-error process. At last, experiments were done on the UCI, KDD Cup 1999, and synthetic datasets, which showed that the method not only effectively determined the optimal number of clusters, but also reduced the iteration of FCM with the stable clustering result. PMID:28042291

  3. Enhancing Self-Efficacy in Elementary Science Teaching with Professional Learning Communities

    Science.gov (United States)

    Mintzes, Joel J.; Marcum, Bev; Messerschmidt-Yates, Christl; Mark, Andrew

    2013-01-01

    Emerging from Bandura's Social Learning Theory, this study of in-service elementary school teachers examined the effects of sustained Professional Learning Communities (PLCs) on self-efficacy in science teaching. Based on mixed research methods, and a non-equivalent control group experimental design, the investigation explored changes in…

  4. Optimization, ex vivo permeation, and stability study of lipid nanocarrier loaded gelatin capsules for treatment of intermittent claudication

    Directory of Open Access Journals (Sweden)

    Sallam MA

    2015-07-01

    Full Text Available Marwa Ahmed Sallam,1 María Teresa Marín Boscá21Department of Industrial Pharmacy, Faculty of Pharmacy, Alexandria University, Alexandria, Egypt; 2Department of Pharmacy and Pharmaceutical Technology, Faculty of Pharmacy, Granada University, Granada, Spain Abstract: In this study, an optimized nanodispersible oral dosage form (containing a lactate ester was developed for cilostazol (CZL. CZL is a phosphodiesterase inhibitor used for intermittent claudication. We aimed to improve the dissolution rate and absorption of CZL giving it a better chance of oral bioavailability, and to evaluate its stability on storage. Suitable compositions of nanoemulsion preconcentrate formulations were screened via solubility and compatibility tests. Response surface methodology and a desirability approach were applied to optimize preconcentrates containing minimum amount of surfactant mixture, maximum amount of lipid, and possessing the smallest globule size, with the highest emulsification and dissolution rates and minimum risk of drug precipitation. As part of the optimization process, the main effect, interaction effects and quadratic effects of amounts of lipid, and surfactant/co-surfactant ratio on % transmittance, globule size, emulsification time, drug precipitation, and drug release were investigated. The optimized formulation consisting of 28.9% butyl lactate, 28.9% Capryol®, 27.82% Solubilisant Gamma® 2429, and 14.18% Transcutol® possessing a globule size of 60 nm was mixed with Aerosil® 200. This gave uniform free flowing granules, which were characterized for surface and powder properties. The self-nanoemulsifying granules (SNEGs filled into hard gelatin capsules showed two- and threefold increase in CZL released compared with conventional tablet and pure drug, respectively. The amount of drug permeated using non-everted sac technique from the SNEGs was twofold higher than that permeated from the tablet suspension. The shelf life was 526 days at

  5. Improved Balance Confidence and Stability for Elderly After 6 Weeks of a Multimodal Self-Administered Balance-Enhancing Exercise Program

    Science.gov (United States)

    Hafström, Anna; Malmström, Eva-Maj; Terdèn, Josefine; Fransson, Per-Anders; Magnusson, Måns

    2016-01-01

    Objective: To develop and assess the efficacy of a multimodal balance-enhancing exercise program (BEEP) designed to be regularly self-administered by community-dwelling elderly. The program aims to promote sensory reweighting, facilitate motor control, improve gaze stabilization, and stimulate continuous improvement by being constantly challenging. Method: Forty participants aged 60 to 80 years performed 6 weeks of BEEP training, on average for 16 min four times weekly, in a randomized one-arm crossover design. Results: One-leg standing time improved 32% with eyes open (EO), 206% with eyes closed (EC) on solid surface, and 54% EO on compliant surface (p balance improvements when perturbed on solid and compliant surfaces with EO and EC (p ≤ .033). Walking, step stool, and Timed Up and Go speeds increased (p ≤ .001), as did scores in Berg Balance and balance confidence scales (p ≤ .018). Discussion: Multimodal balance exercises offer an efficient, cost-effective way to improve balance control and confidence in elderly. PMID:28138495

  6. Economic Optimization Analysis of Chengdu Electric Community Bus Operation

    Science.gov (United States)

    Yidong, Wang; Yun, Cai; Zhengping, Tan; Xiong, Wan

    2018-03-01

    In recent years, the government has strongly supported and promoted electric vehicles and has given priority to demonstration and popularization in the field of public transport. The economy of public transport operations has drawn increasing attention. In this paper, Chengdu wireless charging pure electric community bus is used as the research object, the battery, air conditioning, driver’s driving behavior and other economic influence factors were analyzed, and optimizing the operation plan through case data analysis, through the reasonable battery matching and mode of operation to help businesses effectively save operating costs and enhance economic efficiency.

  7. Optimizing P3HT/PCBM/MWCNT films for increased stability in polymer bulk heterojunction solar cells

    International Nuclear Information System (INIS)

    Singh, Vinamrita; Arora, Swati; Arora, Manoj; Sharma, Vishal; Tandon, R.P.

    2014-01-01

    The effect of multi-walled carbon nanotubes on the properties of P3HT:PCBM based solar cells has been studied. The concentration of MWCNT was optimized at 0.2% and the concentration of P3HT:PCBM was increased from 20mg/ml to 30mg/ml to obtain highest efficiency. An increase in charge carrier mobility was also observed, which is attributed to high charge transport properties of MWCNT. The active layer was optically stable with respect to absorption, whereas the emission spectra revealed an increase in charge recombination with time. The solar cells doped with MWCNT exhibited increased stability as compared to undoped cells. - Highlights: • MWCNT doped P3HT:PCBM based solar cells are optimized for increased efficiency. • Degradation studies showed that MWCNT stabilizes the cell performance. • Mobility and basic device characteristics decreased with time. • Photoluminescence studies with time showed an increase in charge recombination. • Degradation for devices kept in air is faster as compared to the samples in vacuum

  8. Optimizing P3HT/PCBM/MWCNT films for increased stability in polymer bulk heterojunction solar cells

    Energy Technology Data Exchange (ETDEWEB)

    Singh, Vinamrita [Department of Physics and Astrophysics, University of Delhi, Delhi 110007 (India); Arora, Swati, E-mail: drswatia@yahoo.com [Department of Physics, Zakir Husain Delhi College, University of Delhi, Delhi 110002 (India); Arora, Manoj [Department of Physics, Ramjas College, University of Delhi, Delhi 110007 (India); Sharma, Vishal; Tandon, R.P. [Department of Physics and Astrophysics, University of Delhi, Delhi 110007 (India)

    2014-08-22

    The effect of multi-walled carbon nanotubes on the properties of P3HT:PCBM based solar cells has been studied. The concentration of MWCNT was optimized at 0.2% and the concentration of P3HT:PCBM was increased from 20mg/ml to 30mg/ml to obtain highest efficiency. An increase in charge carrier mobility was also observed, which is attributed to high charge transport properties of MWCNT. The active layer was optically stable with respect to absorption, whereas the emission spectra revealed an increase in charge recombination with time. The solar cells doped with MWCNT exhibited increased stability as compared to undoped cells. - Highlights: • MWCNT doped P3HT:PCBM based solar cells are optimized for increased efficiency. • Degradation studies showed that MWCNT stabilizes the cell performance. • Mobility and basic device characteristics decreased with time. • Photoluminescence studies with time showed an increase in charge recombination. • Degradation for devices kept in air is faster as compared to the samples in vacuum.

  9. A Universal Approach to Optimize the Folding and Stability of Prefusion-Closed HIV-1 Envelope Trimers

    Directory of Open Access Journals (Sweden)

    Lucy Rutten

    2018-04-01

    Full Text Available Summary: The heavily glycosylated native-like envelope (Env trimer of HIV-1 is expected to have low immunogenicity, whereas misfolded forms are often highly immunogenic. High-quality correctly folded Envs may therefore be critical for developing a vaccine that induces broadly neutralizing antibodies. Moreover, the high variability of Env may require immunizations with multiple Envs. Here, we report a universal strategy that provides for correctly folded Env trimers of high quality and yield through a repair-and-stabilize approach. In the repair stage, we utilized a consensus strategy that substituted rare strain-specific residues with more prevalent ones. The stabilization stage involved structure-based design and experimental assessment confirmed by crystallographic feedback. Regions important for the refolding of Env were targeted for stabilization. Notably, the α9-helix and an intersubunit β sheet proved to be critical for trimer stability. Our approach provides a means to produce prefusion-closed Env trimers from diverse HIV-1 strains, a substantial advance for vaccine development. : Rutten et al. describe a universal repair and stabilize approach that corrects rare mutations and stabilizes refolding regions to obtain high-quality HIV Envs with high yields. The crystal structure shows how the optimization of the trimer interface between α9, α6, and the intersubunit β-sheet stabilizes the membrane-proximal base. Keywords: envelope protein, chronic, ConC_base, HIV, SOSIP, stabilization, transmitted/founder, vaccine, X-ray structure, hybrid sheet

  10. Supporting self-management by Community Matrons through a group intervention; an action research study.

    Science.gov (United States)

    Barkham, Abigail M; Ersser, Steven J

    2017-07-01

    The aim of this study was to examine the feasibility and impact of a group intervention by Community Matrons to support those living with multiple long-terms conditions. Little evidence exists as to how the role of the Community Matron (CM) should be delivered to effectively enhance disease self-management and levels of self-efficacy for the service users. This qualitative participatory action research study explored the use of group work as a method of intervention by CMs. A purposive sample of 29 participants was recruited. Each patient group had 8-10 participants, led by a CM working in both the researcher and practitioner role, operating over 12-month period. Data were collected by participant observation, researcher reflexive account and interviews. Grounded theory method was used to systematically analyse the data. Three main data categories emerged: (i) comparison by patients that leads to re-motivation of the self; (ii) learning, leading to enhanced self-management techniques, through storytelling and understanding of each other's experiences; and (iii) ownership that resulted in the self-awareness, cognisance and insight into the role of the support group they were based in and how it benefited them. The core category of 'Taking back the self - understanding the whole,' conveyed the impact that this care delivery method had upon readjusting the balance of power between health professional and service users and its consequence in refreshing and improving their self-management and the patients' self-efficacy. It was concluded that CM intervention using a model of group learning can lead to more effective and efficient support, through improving self-efficacy and patients' related self-management ability. © 2017 John Wiley & Sons Ltd.

  11. Community Interactive Processes and Rural Adolescents’ Educational Achievement: Investigating the Mediating Effects of Delinquency and Self-Esteem

    Directory of Open Access Journals (Sweden)

    Omolola A. Adedokun

    2008-09-01

    Full Text Available The study reported in this paper examines the effects of community interactive processes on rural adolescents’ educational achievement. Specifically, the paper explored the direct effects of community interactive processes on rural adolescents’ educational achievement and the indirect effects via self-esteem and delinquency. The method of structural equation modeling was used to analyze data from a nationally representative panel study of rural adolescent boys and girls in 10th grade through 12th grade. The results make a compelling case that communities are conduits for boosting self-esteem, facilitating normative behaviors and academic performance in rural adolescents.

  12. Genetic and environmental etiology of stability and changes in self-esteem linked to personality: A Japanese twin study

    OpenAIRE

    Shikishima, Chizuru; Hiraishi, Kai; Takahashi, Yusuke; Yamagata, Shinji; Yamaguchi, Susumu; Ando, Juko

    2018-01-01

    This study used a behavioral genetic approach to examine the genetic and environmental etiology of stability and changes in self-esteem in relation to personality. Multiple genetic analyses were conducted on a longitudinal dataset of self-esteem and Big Five personality scores among young adult Japanese twins over the course of a decade. There were 1221 individuals for whom data were available on both self-esteem and the Big Five personality test at Time 1 and 365 at Time 2. The mean interval...

  13. Global stability, periodic solutions, and optimal control in a nonlinear differential delay model

    Directory of Open Access Journals (Sweden)

    Anatoli F. Ivanov

    2010-09-01

    Full Text Available A nonlinear differential equation with delay serving as a mathematical model of several applied problems is considered. Sufficient conditions for the global asymptotic stability and for the existence of periodic solutions are given. Two particular applications are treated in detail. The first one is a blood cell production model by Mackey, for which new periodicity criteria are derived. The second application is a modified economic model with delay due to Ramsey. An optimization problem for a maximal consumption is stated and solved for the latter.

  14. COMMUNITY BASED HOME ENERGY MANAGEMENT SYSTEM

    Directory of Open Access Journals (Sweden)

    Muhammad Adnan Aziz

    2017-05-01

    Full Text Available In a Smart Grid (SG scenario, domestic consumers can gain cost reduction benefit by scheduling their Appliance Activation Time (AAT towards the slots of low charge. Minimization in cost is essential in Home Energy Management Systems (HEMS to induce consumers acceptance for power scheduling to accommodate for a Demand Response (DR at peak hours. Despite the fact that many algorithms address the power scheduling for HEMS, community based optimization has not been the focus. This paper presents an algorithm that targets the minimization of energy costs of whole community while keeping a low Peak to Average Ratio (PAR and smooth Power Usage Pattern (PUP. Objective of cost reduction is accomplished by finding most favorable AAT by Particle Swarm Optimization (PSO in conjunction with Inclined Block Rate (IBR approach and Circular Price Shift (CPS. Simulated numerical results demonstrate the effectiveness of CPS to assist the merger of PSO & IBR to enhance the reduction/stability of PAR and cost reduction.

  15. Optimal Controller Design of a Wind Turbine with Doubly Fed Induction Generator for Small Signal Stability Enhancement

    DEFF Research Database (Denmark)

    Yang, Lihui; Yang, Guangya; Xu, Zhao

    2010-01-01

    Multi-objective optimal controller design of a doubly fed induction generator (DFIG) wind turbine system using Differential Evolution (DE) is presented in this chapter. A detailed mathematical model of DFIG wind turbine with a close loop vector control system is developed. Based on this, objective...... functions, addressing the steady state stability and dynamic performance at different operating conditions are implemented to optimize the controller parameters of both the rotor and grid side converters. A superior ε-constraint method and method of adaptive penalties are applied to handle the multi...

  16. Community based physiotherapeutic exercise in COPD self-management: a randomised controlled trial.

    NARCIS (Netherlands)

    Effing, T.; Zielhuis, G.A.; Kerstjens, H.; Valk, P. van der; Palen, J.A.M. van der

    2011-01-01

    Little is known about effects of community-based physiotherapeutic exercise programmes incorporated in COPD self-management programmes. In a randomised trial, the effect of such a programme (COPE-active) on exercise capacity and various secondary outcomes including daily activity as a marker of

  17. Community based psysiotherapeutic exercise in COPD self-management: A randomised controlled trial

    NARCIS (Netherlands)

    Effing, T.W.; Zielhuis, Gerhard; Kerstjens, Huib; van der Valk, Paul; van der Palen, Jacobus Adrianus Maria

    2011-01-01

    Little is known about effects of community-based physiotherapeutic exercise programmes incorporated in COPD self-management programmes. In a randomised trial, the effect of such a programme (COPE-active) on exercise capacity and various secondary outcomes including daily activity as a marker of

  18. Quality of life and self-esteem among the elderly in the community.

    Science.gov (United States)

    Tavares, Darlene Mara Dos Santos; Matias, Thaís Gabriela Cruz; Ferreira, Pollyana Cristina Dos Santos; Pegorari, Maycon Sousa; Nascimento, Janaina Santos; Paiva, Mariana Mapelli de

    2016-11-01

    This study sought to investigate the association between the scores for quality of life (QoL) and self-esteem among the elderly in an urban community. A cross-sectional, quantitative and analytical household survey was conducted with 1,691 elderly persons resident in an urban area in a county in Minas Gerais state. The World Health Organization Quality of Life BREF (WHOQOL-BREF), the World Health Organization Quality of Life OLD (WHOQOL-OLD) questionnaires and the Rosenberg Self-Esteem Scale were used in this study. A descriptive statistical analysis and a linear regression model (p self-esteem scores showed an average of 9.36 ± 4.09. Associations were evident for the lower scores of quality of life in all the WHOQOL-BREF domains and WHOQOL-OLD aspects (except death and dying) with lower levels of self-esteem (p self-esteem, thus providing information for the development of health strategies.

  19. HIV self-testing values and preferences among sex workers, fishermen, and mainland community members in Rakai, Uganda: A qualitative study.

    Directory of Open Access Journals (Sweden)

    Virginia M Burke

    Full Text Available HIV self-testing may encourage greater uptake of testing, particularly among key populations and other high-risk groups, but local community perceptions will influence test uptake and use. We conducted 33 in-depth interviews and 6 focus group discussions with healthcare providers and community members in high-risk fishing communities (including sex workers and fishermen and lower-risk mainland communities in rural Uganda to evaluate values and preferences around HIV self-testing. While most participants were unfamiliar with HIV self-testing, they cited a range of potential benefits, including privacy, convenience, and ability to test before sex. Concerns focused on the absence of a health professional, risks of careless kit disposal and limited linkage to care. Participants also discussed issues of kit distribution strategies and cost, among others. Ultimately, most participants concluded that benefits outweighed risks. Our findings suggest a potential role for HIV self-testing across populations in these settings, particularly among these key populations. Program implementers will need to consider how to balance HIV self-testing accessibility with necessary professional support.

  20. Effect of Graphene-EC on Ag NW-Based Transparent Film Heaters: Optimizing the Stability and Heat Dispersion of Films.

    Science.gov (United States)

    Cao, Minghui; Wang, Minqiang; Li, Le; Qiu, Hengwei; Yang, Zhi

    2018-01-10

    To optimize the performance of silver nanowire (Ag NW) film heaters and explore the effect of graphene on a film, we introduced poly(3,4-ethylenedioxythiophene):poly(4-styrenesulfonate) (PEDOT:PSS) and graphene modified with ethyl cellulose (graphene-EC) into the film. The high-quality and well-dispersed graphene-EC was synthesized from graphene obtained by electrochemical exfoliation as a precursor. The transparent film heaters were fabricated via spin-coating. With the assistance of graphene-EC, the stability of film heaters was greatly improved, and the conductivity was optimized by adjusting the Ag NW concentration. The film heaters exhibited a fast and accurate response to voltage, accompanied by excellent environmental endurance, and there was no significant performance degradation after being operated for a long period of time. These results indicate that graphene-EC plays a crucial role in optimizing film stability and heat dispersion in the film. The Ag NW/PEDOT:PSS-doped graphene-EC film heaters show a great potential in low-cost indium-tin-oxide-free flexible transparent electrodes, heating systems, and transparent film heaters.

  1. Optimal Design of Rectification Circuit in Electronic Circuit Fault Self-repair Based on EHW and RBT

    Institute of Scientific and Technical Information of China (English)

    ZHANG Junbin; CAI Jinyan; MENG Yafeng

    2018-01-01

    Reliability of traditional electronic circuit is improved mainly by redundant fault-tolerant technol-ogy with large hardware resource consumption and limited fault self-repair capability. In complicated environment, electronic circuit faults appear easily. If on-site immedi-ate repair is not implemented, normal running of elec-tronic system will be directly affected. In order to solve these problems, Evolvable hardware (EHW) technology is widely used. The conventional EHW has some bottlenecks. The optimal design of Rectification circuit (RTC) is fur-ther researched on the basis of the previously proposed fault self-repair based on EHW and Reparation balance technology (RBT). Fault sets are selected by fault danger degree and fault coverage rate. The optimal designed RTC can completely repair faults in the fault set. Simulation re-sults prove that it has higher self-repair capability and less hardware resource.

  2. Deliberate Self-Harm within an International Community Sample of Young People: Comparative Findings from the Child & Adolescent Self-Harm in Europe (CASE) Study

    Science.gov (United States)

    Madge, Nicola; Hewitt, Anthea; Hawton, Keith; de Wilde, Erik Jan; Corcoran, Paul; Fekete, Sandor; van Heeringen, Kees; De Leo, Diego; Ystgaard, Mette

    2008-01-01

    Background: Deliberate self-harm among young people is an important focus of policy and practice internationally. Nonetheless, there is little reliable comparative international information on its extent or characteristics. We have conducted a seven-country comparative community study of deliberate self-harm among young people. Method: Over 30,000…

  3. A novel self-organizing E-Learner community model with award and exchange mechanisms.

    Science.gov (United States)

    Yang, Fan; Shen, Rui-min; Han, Peng

    2004-11-01

    How to share experience and resources among learners is becoming one of the hottest topics in the field of E-Learning collaborative techniques. An intuitive way to achieve this objective is to group learners which can help each other into the same community and help them learn collaboratively. In this paper, we proposed a novel community self-organization model based on multi-agent mechanism, which can automatically group learners with similar preferences and capabilities. In particular, we proposed award and exchange schemas with evaluation and preference track records to raise the performance of this algorithm. The description of learner capability, the matchmaking process, the definition of evaluation and preference track records, the rules of award and exchange schemas and the self-organization algorithm are all discussed in this paper. Meanwhile, a prototype has been built to verify the validity and efficiency of the algorithm. Experiments based on real learner data showed that this mechanism can organize learner communities properly and efficiently; and that it has sustainable improved efficiency and scalability.

  4. Pre-genomic, genomic and post-genomic study of microbial communities involved in bioenergy.

    Science.gov (United States)

    Rittmann, Bruce E; Krajmalnik-Brown, Rosa; Halden, Rolf U

    2008-08-01

    Microorganisms can produce renewable energy in large quantities and without damaging the environment or disrupting food supply. The microbial communities must be robust and self-stabilizing, and their essential syntrophies must be managed. Pre-genomic, genomic and post-genomic tools can provide crucial information about the structure and function of these microbial communities. Applying these tools will help accelerate the rate at which microbial bioenergy processes move from intriguing science to real-world practice.

  5. Barriers and facilitators to diabetes self-management: perspectives of older community dwellers and health professionals in China.

    Science.gov (United States)

    Shen, Huixia; Edwards, Helen; Courtney, Mary; McDowell, Jan; Wei, Juan

    2013-12-01

    Little is known about self-management among people with Type 2 diabetes living in mainland China. Understanding the experiences of this target population is needed to provide socioculturally relevant education to effectively promote self-management. The aim of this study was to explore perceived barriers and facilitators to diabetes self-management for both older community dwellers and health professionals in China. Four focus groups, two for older people with diabetes and two for health professionals, were conducted. All participants were purposively sampled from two communities in Shanghai, China. Six barriers were identified: overdependence on but dislike of western medicine, family role expectations, cuisine culture, lack of trustworthy information sources, deficits in communication between clients and health professionals, and restriction of reimbursement regulations. Facilitators included family and peer support, good relationships with health professionals, simple and practical instruction and a favourable community environment. The findings provide valuable information for diabetes self-management intervention development in China, and have implications for programmes tailored to populations in similar sociocultural circumstances. © 2013 Wiley Publishing Asia Pty Ltd.

  6. A Community-based Healthy Living Promotion Program Improved Self-esteem Among Minority Children.

    Science.gov (United States)

    Wong, William W; Ortiz, Christina L; Stuff, Janice E; Mikhail, Carmen; Lathan, Debra; Moore, Louis A; Alejandro, Mercedes E; Butte, Nancy F; Smith, Elliot O'Brian

    2016-07-01

    Improving self-esteem, dietary habits, and physical activity is essential for long-term success in childhood obesity prevention. The aim is to evaluate the effects of a healthy living promotion program, Healthy Kids-Houston, on BMI, dietary habits, self-esteem, and physical activity among minority children. The after-school program was implemented at community centers in low-income neighborhoods with close proximity to public schools. The program consisted of 3 6-week sessions. Each week, children attended 2 2-hour sessions. Each 2-hour session in the intervention included 90 minutes of structured physical activities and 30 minutes of nutrition and healthy habit lessons. The control group received typical enrichment programs. Outcomes were measured before the intervention and at the end of each 6-week session. We enrolled 877 children (age 10.2 ± 0.1 years (mean ± SE); body mass index z score: 1.49 ± 0.1; 52.0% boys; 72.6% Hispanic) in the program with 524 children received the intervention at 14 community centers and 353 children served as control at 10 community centers. The intervention led to no improvements in BMI z score (P = 0.78) and dietary habits (P = 0.46). Significant improvements (P ≤ 0.02) were detected in the amount of exercise that a child perceived to be required to offset a large meal and in several key self-esteem scores. No improvements were detected in physical activities (P ≥ 0.21). The improvement in some key self-esteem scores and nutrition knowledge may act as a mediator to motivate these children to adopt a healthier lifestyle in the future.

  7. Development and optimization of a self-microemulsifying drug delivery system for atorvastatin calcium by using D-optimal mixture design.

    Science.gov (United States)

    Yeom, Dong Woo; Song, Ye Seul; Kim, Sung Rae; Lee, Sang Gon; Kang, Min Hyung; Lee, Sangkil; Choi, Young Wook

    2015-01-01

    In this study, we developed and optimized a self-microemulsifying drug delivery system (SMEDDS) formulation for improving the dissolution and oral absorption of atorvastatin calcium (ATV), a poorly water-soluble drug. Solubility and emulsification tests were performed to select a suitable combination of oil, surfactant, and cosurfactant. A D-optimal mixture design was used to optimize the concentration of components used in the SMEDDS formulation for achieving excellent physicochemical characteristics, such as small droplet size and high dissolution. The optimized ATV-loaded SMEDDS formulation containing 7.16% Capmul MCM (oil), 48.25% Tween 20 (surfactant), and 44.59% Tetraglycol (cosurfactant) significantly enhanced the dissolution rate of ATV in different types of medium, including simulated intestinal fluid, simulated gastric fluid, and distilled water, compared with ATV suspension. Good agreement was observed between predicted and experimental values for mean droplet size and percentage of the drug released in 15 minutes. Further, pharmacokinetic studies in rats showed that the optimized SMEDDS formulation considerably enhanced the oral absorption of ATV, with 3.4-fold and 4.3-fold increases in the area under the concentration-time curve and time taken to reach peak plasma concentration, respectively, when compared with the ATV suspension. Thus, we successfully developed an optimized ATV-loaded SMEDDS formulation by using the D-optimal mixture design, that could potentially be used for improving the oral absorption of poorly water-soluble drugs.

  8. Integrated Traction Control Strategy for Distributed Drive Electric Vehicles with Improvement of Economy and Longitudinal Driving Stability

    Directory of Open Access Journals (Sweden)

    Xudong Zhang

    2017-01-01

    Full Text Available This paper presents an integrated traction control strategy (ITCS for distributed drive electric vehicles. The purpose of the proposed strategy is to improve vehicle economy and longitudinal driving stability. On high adhesion roads, economy optimization algorithm is applied to maximize motors efficiency by means of the optimized torque distribution. On low adhesion roads, a sliding mode control (SMC algorithm is implemented to guarantee the wheel slip ratio around the optimal slip ratio point to make full use of road adhesion capacity. In order to avoid the disturbance on slip ratio calculation due to the low vehicle speed, wheel rotational speed is taken as the control variable. Since the optimal slip ratio varies according to different road conditions, Bayesian hypothesis selection is utilized to estimate the road friction coefficient. Additionally, the ITCS is designed for combining the vehicle economy and stability control through three traction allocation cases: economy-based traction allocation, pedal self-correcting traction allocation and inter-axles traction allocation. Finally, simulations are conducted in CarSim and Matlab/Simulink environment. The results show that the proposed strategy effectively reduces vehicle energy consumption, suppresses wheels-skid and enhances the vehicle longitudinal stability and dynamic performance.

  9. The effect of metacognitive self on confirmation bias revealed in relation to community and competence

    Directory of Open Access Journals (Sweden)

    Brycz Hanna

    2014-09-01

    Full Text Available The main goal of our study was to investigate the role of insight into one’s own biases (metacognitive self in the process of hypothesis validation in accordance to the two fundamental social perception domains (community and competence on the example of confirmation bias. The study was conducted on a group of 593 participants with the use of a confirmation bias procedure, a free recall procedure and the Metacognitive Self scale. We manipulated with the domain and the value of information given to the respondents. We suspected that individuals with a high metacognitive self, in opposition to low metacognitive self ones, would not process the given information according to the two fundamental social perception domains. The results verified the existence of an interaction effect of the metacognitive self (MCS and the domain of the information given about a perceived person on the susceptibility to follow the confirmation bias. Contrary to the low metacognitive self individuals, who show a higher tendency for the confirmation bias within the competence than the community domain, persons with a high insight into their own biases express the same level of confirmation bias in no respect to the domain of the information. The value of the information has no significant influence.

  10. Self-pinched lithium beam transport experiments on SABRE

    International Nuclear Information System (INIS)

    Hanson, D.L.; Olson, C.L.; Poukey, J.W.; Shokir, I.; Cuneo, M.E.; Menge, P.R.; Johnston, R.R.; Welch, D.R.

    1996-01-01

    Self-pinched transport of ion beams has many advantages for ion-driven ICF applications involving high yield and energy production. The authors are currently preparing for a self-pinched lithium beam transport experiment on the SABRE accelerator. There are three transport elements that must eventually be demonstrated: (1) efficient lithium beam generation and ballistic transport to a focus at the self-pinched transport channel entrance; (2) self-pinched transport in the channel, requiring optimized injection conditions and gas breakdown; and (3) self-pinched transport of the equilibrated beam from the channel into free space, with associated aiming and stability considerations. In the present experiment, a hollow annular lithium beam from an applied-B extraction ion diode will be focused to small radius (r ≤ 2 cm) in a 60 cm long ballistic focus section containing argon gas at a pressure of a few Torr. The self-pinched transport channel will contain a low pressure background gas of 10--40 mTorr argon to allow sufficient net current to confine the beam for long distance transport. IPROP simulations are in progress to optimize the design of the ballistic and self-pinched transport sections. Progress on preparation of this lithium self-pinched transport experiment, including a discussion of transport system design, important gas breakdown issues, and diagnostics, will be presented

  11. Self-stabilized discharge filament in plane-parallel barrier discharge configuration: formation, breakdown mechanism, and memory effects

    Science.gov (United States)

    Tschiersch, R.; Nemschokmichal, S.; Bogaczyk, M.; Meichsner, J.

    2017-10-01

    Single self-stabilized discharge filaments were investigated in the plane-parallel electrode configuration. The barrier discharge was operated inside a gap of 3 mm shielded by glass plates to both electrodes, using helium-nitrogen mixtures and a square-wave feeding voltage at a frequency of 2 kHz. The combined application of electrical measurements, ICCD camera imaging, optical emission spectroscopy and surface charge diagnostics via the electro-optic Pockels effect allowed the correlation of the discharge development in the volume and on the dielectric surfaces. The formation criteria and existence regimes were found by systematic variation of the nitrogen admixture to helium, the total pressure and the feeding voltage amplitude. Single self-stabilized discharge filaments can be operated over a wide parameter range, foremost, by significant reduction of the voltage amplitude after the operation in the microdischarge regime. Here, the outstanding importance of the surface charge memory effect on the long-term stability was pointed out by the recalculated spatio-temporally resolved gap voltage. The optical emission revealed discharge characteristics that are partially reminiscent of both the glow-like barrier discharge and the microdischarge regime, such as a Townsend pre-phase, a fast cathode-directed ionization front during the breakdown and radially propagating surface discharges during the afterglow.

  12. Parallel Optimization of Polynomials for Large-scale Problems in Stability and Control

    Science.gov (United States)

    Kamyar, Reza

    In this thesis, we focus on some of the NP-hard problems in control theory. Thanks to the converse Lyapunov theory, these problems can often be modeled as optimization over polynomials. To avoid the problem of intractability, we establish a trade off between accuracy and complexity. In particular, we develop a sequence of tractable optimization problems --- in the form of Linear Programs (LPs) and/or Semi-Definite Programs (SDPs) --- whose solutions converge to the exact solution of the NP-hard problem. However, the computational and memory complexity of these LPs and SDPs grow exponentially with the progress of the sequence - meaning that improving the accuracy of the solutions requires solving SDPs with tens of thousands of decision variables and constraints. Setting up and solving such problems is a significant challenge. The existing optimization algorithms and software are only designed to use desktop computers or small cluster computers --- machines which do not have sufficient memory for solving such large SDPs. Moreover, the speed-up of these algorithms does not scale beyond dozens of processors. This in fact is the reason we seek parallel algorithms for setting-up and solving large SDPs on large cluster- and/or super-computers. We propose parallel algorithms for stability analysis of two classes of systems: 1) Linear systems with a large number of uncertain parameters; 2) Nonlinear systems defined by polynomial vector fields. First, we develop a distributed parallel algorithm which applies Polya's and/or Handelman's theorems to some variants of parameter-dependent Lyapunov inequalities with parameters defined over the standard simplex. The result is a sequence of SDPs which possess a block-diagonal structure. We then develop a parallel SDP solver which exploits this structure in order to map the computation, memory and communication to a distributed parallel environment. Numerical tests on a supercomputer demonstrate the ability of the algorithm to

  13. Japanese Culture and the Philosophy of Self-Advocacy: The Importance of Interdependence in Community Living

    Science.gov (United States)

    Tsuda, Eiji

    2006-01-01

    In Japan, there is a growing network of self-advocacy groups. Some groups are involved in campaigning. Other groups are involved in social events and education. The age of de-institutionalization is gradually arriving and community living for people with learning difficulties is becoming an urgent political issue. Self-advocacy groups can help…

  14. Autonomous informational stability in connective tissues.

    Science.gov (United States)

    Brand, R A

    1992-02-01

    No coherent theories currently explain connective tissue stability (i.e. 'memory') as well as spatial and temporal adaptability in the face of continual flux of its constituents. Furthermore, explanations of stability based exclusively upon DNA raise certain inherent problems, particularly with the spatial concordance of somatic tissues. As an alternative explanation, it is hypothesized that while connective tissue cells produce extracellular protein precursors through DNA-dependent processes, the assembly, location, orientation and configuration of the extracellular macromolecules as well as their degree of cell attachment depend primarily upon local micro-environmental conditions and/or self-organization rather than strictly cellular processes. The resulting extracellular matrix (ECM) serves as a time- and spatially-variable filter about each cell to afford a relatively consistent micro-environment for all similar cells, regardless of the more variable macro-environment. By insuring a consistent set of signals to the cell, the filter provides a non-genetic memory complementary to genetic memory. The half-lives of constituent molecules define the duration of the filter, allowing the filter to adapt to new environmental demands, yet to maintain a consistent milieu for the cell. The cell/matrix construct permits local, self-optimizing, non-deterministic tissue autonomy obviating the need to postulate certain intricate mechanisms coordinating spatial morphology and temporal behavior.

  15. Self-assembling peptides form nanodiscs that stabilize membrane proteins

    DEFF Research Database (Denmark)

    Midtgaard, Søren Roi; Pedersen, Martin Cramer; Kirkensgaard, Jacob Judas Kain

    2014-01-01

    -ray scattering (SAXS) and small-angle neutron scattering (SANS) supported by coarse-grained molecular dynamics simulations. The detailed structure of the discs was determined in unprecedented detail and it was found that they adopt a discoidal structure very similar to the ApoA1 based nanodiscs. We furthermore...... show that, like the ApoA1 and derived nanodiscs, these peptide discs can accommodate and stabilize a membrane protein. Finally, we exploit their dynamic properties and show that the 18A discs may be used for transferring membrane proteins and associated phospholipids directly and gently......New methods to handle membrane bound proteins, e.g. G-protein coupled receptors (GPCRs), are highly desirable. Recently, apoliprotein A1 (ApoA1) based lipoprotein particles have emerged as a new platform for studying membrane proteins, and it has been shown that they can self...

  16. Multi-Layer Self-Nanoemulsifying Pellets: an Innovative Drug Delivery System for the Poorly Water-Soluble Drug Cinnarizine.

    Science.gov (United States)

    Shahba, Ahmad Abdul-Wahhab; Ahmed, Abid Riaz; Alanazi, Fars Kaed; Mohsin, Kazi; Abdel-Rahman, Sayed Ibrahim

    2018-04-25

    Beside their solubility limitations, some poorly water-soluble drugs undergo extensive degradation in aqueous and/or lipid-based formulations. Multi-layer self-nanoemulsifying pellets (ML-SNEP) introduce an innovative delivery system based on isolating the drug from the self-nanoemulsifying layer to enhance drug aqueous solubility and minimize degradation. In the current study, various batches of cinnarizine (CN) ML-SNEP were prepared using fluid bed coating and involved a drug-free self-nanoemulsifying layer, protective layer, drug layer, moisture-sealing layer, and/or an anti-adherent layer. Each layer was optimized based on coating outcomes such as coating recovery and mono-pellets%. The optimized ML-SNEP were characterized using scanning electron microscopy (SEM), differential scanning calorimetry (DSC), X-ray diffraction (XRD), in vitro dissolution, and stability studies. The optimized ML-SNEP were free-flowing, well separated with high coating recovery. SEM showed multiple well-defined coating layers. The acidic polyvinylpyrrolidone:CN (4:1) solution presented excellent drug-layering outcomes. DSC and XRD confirmed CN transformation into amorphous state within the drug layer. The isolation between CN and self-nanoemulsifying layer did not adversely affect drug dissolution. CN was able to spontaneously migrate into the micelles arising from the drug-free self-nanoemulsifying layer. ML-SNEP showed superior dissolution compared to Stugeron® tablets at pH 1.2 and 6.8. Particularly, on shifting to pH 6.8, ML-SNEP maintained > 84% CN in solution while Stugeron® tablets showed significant CN precipitation leaving only 7% CN in solution. Furthermore, ML-SNEP (comprising Kollicoat® Smartseal 30D) showed robust stability and maintained > 97% intact CN within the accelerated storage conditions. Accordingly, ML-SNEP offer a novel delivery system that combines both enhanced solubilization and stabilization of unstable poorly soluble drugs.

  17. Dynamic stability of nano-fibers self-assembled from short amphiphilic A6D peptides.

    Science.gov (United States)

    Nikoofard, Narges; Maghsoodi, Fahimeh

    2018-04-07

    Self-assembly of A 6 D amphiphilic peptides in explicit water is studied by using coarse-grained molecular dynamics simulations. It is observed that the self-assembly of randomly distributed A 6 D peptides leads to the formation of a network of nano-fibers. Two other simulations with cylindrical nano-fibers as the initial configuration show the dynamic stability of the self-assembled nano-fibers. As a striking feature, notable fluctuations occur along the axes of the nano-fibers. Depending on the number of peptides per unit length of the nano-fiber, flat-shaped bulges or spiral shapes along the nano-fiber axis are observed at the fluctuations. Analysis of the particle distribution around the nano-fiber indicates that the hydrophobic core and the hydrophilic shell of the nano-structure are preserved in both simulations. The size of the deformations and their correlation times are different in the two simulations. This study gives new insights into the dynamics of the self-assembled nano-structures of short amphiphilic peptides.

  18. Dynamic stability of nano-fibers self-assembled from short amphiphilic A6D peptides

    Science.gov (United States)

    Nikoofard, Narges; Maghsoodi, Fahimeh

    2018-04-01

    Self-assembly of A6D amphiphilic peptides in explicit water is studied by using coarse-grained molecular dynamics simulations. It is observed that the self-assembly of randomly distributed A6D peptides leads to the formation of a network of nano-fibers. Two other simulations with cylindrical nano-fibers as the initial configuration show the dynamic stability of the self-assembled nano-fibers. As a striking feature, notable fluctuations occur along the axes of the nano-fibers. Depending on the number of peptides per unit length of the nano-fiber, flat-shaped bulges or spiral shapes along the nano-fiber axis are observed at the fluctuations. Analysis of the particle distribution around the nano-fiber indicates that the hydrophobic core and the hydrophilic shell of the nano-structure are preserved in both simulations. The size of the deformations and their correlation times are different in the two simulations. This study gives new insights into the dynamics of the self-assembled nano-structures of short amphiphilic peptides.

  19. Computational optimization techniques applied to microgrids planning

    DEFF Research Database (Denmark)

    Gamarra, Carlos; Guerrero, Josep M.

    2015-01-01

    Microgrids are expected to become part of the next electric power system evolution, not only in rural and remote areas but also in urban communities. Since microgrids are expected to coexist with traditional power grids (such as district heating does with traditional heating systems......), their planning process must be addressed to economic feasibility, as a long-term stability guarantee. Planning a microgrid is a complex process due to existing alternatives, goals, constraints and uncertainties. Usually planning goals conflict each other and, as a consequence, different optimization problems...... appear along the planning process. In this context, technical literature about optimization techniques applied to microgrid planning have been reviewed and the guidelines for innovative planning methodologies focused on economic feasibility can be defined. Finally, some trending techniques and new...

  20. Multi-objective optimization of p-xylene oxidation process using an improved self-adaptive differential evolution algorithm

    Institute of Scientific and Technical Information of China (English)

    Lili Tao; Bin Xu; Zhihua Hu; Weimin Zhong

    2017-01-01

    The rise in the use of global polyester fiber contributed to strong demand of the Terephthalic acid (TPA). The liquid-phase catalytic oxidation of p-xylene (PX) to TPA is regarded as a critical and efficient chemical process in industry [1]. PX oxidation reaction involves many complex side reactions, among which acetic acid combustion and PX combustion are the most important. As the target product of this oxidation process, the quality and yield of TPA are of great concern. However, the improvement of the qualified product yield can bring about the high energy consumption, which means that the economic objectives of this process cannot be achieved simulta-neously because the two objectives are in conflict with each other. In this paper, an improved self-adaptive multi-objective differential evolution algorithm was proposed to handle the multi-objective optimization prob-lems. The immune concept is introduced to the self-adaptive multi-objective differential evolution algorithm (SADE) to strengthen the local search ability and optimization accuracy. The proposed algorithm is successfully tested on several benchmark test problems, and the performance measures such as convergence and divergence metrics are calculated. Subsequently, the multi-objective optimization of an industrial PX oxidation process is carried out using the proposed immune self-adaptive multi-objective differential evolution algorithm (ISADE). Optimization results indicate that application of ISADE can greatly improve the yield of TPA with low combustion loss without degenerating TA quality.

  1. Energy self-sufficient sewage wastewater treatment plants: is optimized anaerobic sludge digestion the key?

    Science.gov (United States)

    Jenicek, P; Kutil, J; Benes, O; Todt, V; Zabranska, J; Dohanyos, M

    2013-01-01

    The anaerobic digestion of primary and waste activated sludge generates biogas that can be converted into energy to power the operation of a sewage wastewater treatment plant (WWTP). But can the biogas generated by anaerobic sludge digestion ever completely satisfy the electricity requirements of a WWTP with 'standard' energy consumption (i.e. industrial pollution not treated, no external organic substrate added)? With this question in mind, we optimized biogas production at Prague's Central Wastewater Treatment Plant in the following ways: enhanced primary sludge separation; thickened waste activated sludge; implemented a lysate centrifuge; increased operational temperature; improved digester mixing. With these optimizations, biogas production increased significantly to 12.5 m(3) per population equivalent per year. In turn, this led to an equally significant increase in specific energy production from approximately 15 to 23.5 kWh per population equivalent per year. We compared these full-scale results with those obtained from WWTPs that are already energy self-sufficient, but have exceptionally low energy consumption. Both our results and our analysis suggest that, with the correct optimization of anaerobic digestion technology, even WWTPs with 'standard' energy consumption can either attain or come close to attaining energy self-sufficiency.

  2. The effect of perceived organisational support on burnout among community health nurses in China: the mediating role of professional self-concept.

    Science.gov (United States)

    Cao, Xiaoyi; Chen, Lin; Tian, Lang; Diao, Yongshu

    2016-01-01

    To examine the mediating effect of professional self-concept on the association between perceived organisational support and burnout among community health nurses in Chengdu, China. Burnout is a common phenomenon among nurses and previous studies have focused on work environmental factors contributing to burnout. Limited studies have examined the effects of perceived organisational support and professional self-concept on burnout among community health nurses. This was a cross-sectional study with 551 community health nurses in Chengdu, China, which included a two-stage sampling method. Structural equation modelling was used to examine the relationships among perceived organisational support, professional self-concept and burnout. The final sample included 456 nurses (82.7%). Perceived organisational support was a significant positive direct predictor for professional self-concept and a significant negative direct predictor for burnout. Professional self-concept was a significant negative direct contributor to burnout. Professional self-concept had a mediating effect on the relationship between perceived organisational support and burnout. Perceived organisational support may result in reduced burnout by facilitating the development of positive professional self-concept. Strategies such as establishing a supportive work environment and professional competence training may be effective methods for burnout prevention and management among community health nurses. © 2015 John Wiley & Sons Ltd.

  3. Relationship between Optimism, Religiosity and Self-Esteem with Marital Satisfaction and Life Satisfaction

    Science.gov (United States)

    Homaei, Rezvan; Bozorgi, Zahra Dasht; Ghahfarokhi, Maryam Sadat Mirbabaei; Hosseinpour, Shima

    2016-01-01

    The purpose of the current study is to investigate the relationship between Optimism, Religiosity and Self-esteem with Marital Satisfaction and Life Satisfaction in married university students. The research method was a descriptive study kind of correlation. The sample group included 200 married students that were selected using a simple random…

  4. Mineral and organic growing media have distinct community structure, stability and functionality in soilless culture systems.

    Science.gov (United States)

    Grunert, Oliver; Hernandez-Sanabria, Emma; Vilchez-Vargas, Ramiro; Jauregui, Ruy; Pieper, Dietmar H; Perneel, Maaike; Van Labeke, Marie-Christine; Reheul, Dirk; Boon, Nico

    2016-01-05

    The choice of soilless growing medium for plant nutrition, growth and support is crucial for improving the eco-sustainability of the production in horticultural systems. As our current understanding of the functional microbial communities inhabiting this ecosystem is still limited, we examined the microbial community development of the two most important growing media (organic and mineral) used in open soilless horticultural systems. We aimed to identify factors that influence community composition over time, and to compare the distribution of individual taxa across growing media, and their potential functionality. High throughput sequencing analysis revealed a distinctive and stable microbial community in the organic growing medium. Humidity, pH, nitrate-N, ammonium-N and conductivity were uncovered as the main factors associated with the resident bacterial communities. Ammonium-N was correlated with Rhizobiaceae abundance, while potential competitive interactions among both Methylophilaceae and Actinobacteridae with Rhizobiaceae were suggested. Our results revealed that soilless growing media are unique niches for diverse bacterial communities with temporal functional stability, which may possibly impact the resistance to external forces. These differences in communities can be used to develop strategies to move towards a sustainable horticulture with increased productivity and quality.

  5. Promotion of oral health by community nurses.

    Science.gov (United States)

    Garry, Brendan; Boran, Sue

    2017-10-02

    To explore the enablers and barriers perceived by community nurses in the promotion of oral health in an adult community trust directorate. Oral health care promotion in community care settings is being neglected. England and Wales have witnessed marked improvements in periodontal disease; however, no improvements have been seen in older people. A qualitative methodology was employed, where eight nurses from Band 5 to 7 were interviewed using a semi-structured approach. The data was analysed thematically. Data analysis was organised into four themes: professional self-concept and the development of knowledge, skills and attitudes necessary in the promotion of oral health; the impact an organisation has on the promotion of oral health and an exploration of the enablers and barriers identified by the community nurses while delivering care; the relationships between the nurse and patient and the potential impact on oral health promotion; the concept of self-regard in relation to the promotion of oral health and its overall impact. A commitment to improving oral health and requests for additional educational input were apparent. Organisational enablers and barriers were identified, alongside the crucial role a positive self-regard for oral health care may play in the promotion of oral health. Nurses need relevant education, organisational support, adequate resources and support from a multidisciplinary team to deliver optimal oral health promotion.

  6. Persistence and stability of fish community structure in a southwest New York stream

    Science.gov (United States)

    Hansen, Michael J.; Ramm, Carl W.

    1994-01-01

    We used multivariate and nonparametric statistics to examine persistence and stability of fish species in the upper 43 km of French Creek, New York. Species occurred in upstream and downstream groups in 1937 that persisted in 1979. However, the downstream group expanded its range in the drainage from 1937 to 1979 at the expense of the upstream group. A dam prevented further upstream expansion of the downstream group. Ranks of species abundances were stable, as tests of group similarity were significant. The abundances and distributions of benthic species were stable across seven sampling dates in 1980 despite several floods and repeated removals by sampling that could have altered community structure. We conclude that the fish community in French Creek persisted and was stable over the 42-yr interval, 1937-1979, and that abundances of benthic species were stable in summer 1980.

  7. Falls self-efficacy and falls incidence in community-dwelling older people: the mediating role of coping.

    Science.gov (United States)

    Loft, Christine C; Jones, Fergal W; Kneebone, Ian I

    2017-11-08

    A cognitive behavioral model predicts that coping responses mediate the relationship between falls related psychological concerns and falls incidence, in community-dwelling older people. If empirical support could be found for this pathway then interventions could be developed to reduce falls risk by targeting coping strategies. Therefore, this study aimed to begin the process of testing whether coping responses mediate the association between falls self-efficacy (a principal element of falls related psychological concerns) and falls incidence, in community-dwelling older people. In a cross-sectional design, 160 community-dwelling older people (31 male, 129 female; mean age 83.47 years) completed the Falls Efficacy Scale-International, the Revised-Ways of Coping Questionnaire, the Turning to Religion subscale of the COPE, and a falls questionnaire. Data were analyzed via mediation analysis using a bootstrapping approach. Lower falls self-efficacy was associated with higher falls incidence, and more self-controlling coping was found to be a partial mediator of this association, with a confidence interval for the indirect effect of (0.003, 0.021) and an effect size of κ 2 = 0.035. The association was not mediated by the other measured coping responses; namely, turning to religion, distancing, seeking social support, accepting responsibility, escape-avoidance, planful problem-solving, and positive reappraisal. Self-controlling coping may mediate the association between falls self-efficacy and falling. If longitudinal studies confirm this finding then coping could be targeted in interventions to reduce falls.

  8. On the optimization of a steady-state bootstrap-reactor

    International Nuclear Information System (INIS)

    Polevoy, A.R.; Martynov, A.A.; Medvedev, S.Yu.

    1993-01-01

    A commercial fusion tokamak-reactor may be economically acceptable only for low recirculating power fraction r 0 ≡ P CD /P α BS ≡I BS /I > 0.9 to sustain the steady-state operation mode for high plasma densities > 1.5 10 20 m -3 , fulfilled the divertor conditions. This paper presents the approximate expressions for the optimal set of reactor parameters for r BS /I∼1, based on the self-consistent plasma simulations by 1.5D ASTRA code. The linear MHD stability analysis for ideal n=1 kink and ballooning modes has been carried out to determine the conditions of stabilization for bootstrap steady state tokamak reactor BSSTR configurations. (author) 10 refs., 1 tab

  9. The social educator as manager of self- managed communities towards a didactics of group work

    Directory of Open Access Journals (Sweden)

    Carlos G. Juliao Vargas

    2005-02-01

    Full Text Available This paper seeks to reflect upon the function of social educators as promoters of self-managing communities as well as to outline the didactic contribution which group work techniques provide for this task. Therefore, the competencies that a social educator should have been addressed from a trace concept of “community” and its relationship whit social education as a non formal process; principally insisting on its role as “leader” of the self-management community processes: how far Leadership should go and where it should stop. It can be concluded that the social educator is required to work among groups of human beings with the main purpose of arousing the collective processes of teaching and learning of knowledge, attitudes and strategies. These strategies lead communities to manage the environment in which they live in an autonomous way so that decent living conditions are guaranteed for everyone. 

  10. Determination of optimal self-drive tourism route using the orienteering problem method

    Science.gov (United States)

    Hashim, Zakiah; Ismail, Wan Rosmanira; Ahmad, Norfaieqah

    2013-04-01

    This paper was conducted to determine the optimal travel routes for self-drive tourism based on the allocation of time and expense by maximizing the amount of attraction scores assigned to each city involved. Self-drive tourism represents a type of tourism where tourists hire or travel by their own vehicle. It only involves a tourist destination which can be linked with a network of roads. Normally, the traveling salesman problem (TSP) and multiple traveling salesman problems (MTSP) method were used in the minimization problem such as determination the shortest time or distance traveled. This paper involved an alternative approach for maximization method which is maximize the attraction scores and tested on tourism data for ten cities in Kedah. A set of priority scores are used to set the attraction score at each city. The classical approach of the orienteering problem was used to determine the optimal travel route. This approach is extended to the team orienteering problem and the two methods were compared. These two models have been solved by using LINGO12.0 software. The results indicate that the model involving the team orienteering problem provides a more appropriate solution compared to the orienteering problem model.

  11. Freeze drying optimization of polymeric nanoparticles for ocular flurbiprofen delivery: effect of protectant agents and critical process parameters on long-term stability.

    Science.gov (United States)

    Ramos Yacasi, Gladys Rosario; Calpena Campmany, Ana Cristina; Egea Gras, María Antonia; Espina García, Marta; García López, María Luisa

    2017-04-01

    The stabilization of flurbiprofen loaded poly-ɛ-caprolactone nanoparticles (FB-PɛCL-NPs) for ocular delivery under accurate freeze-drying (FD) process provides the basis for a large-scale production and its commercial development. Optimization of the FD to improve long-term stability of ocular administration's FB-PɛCL-NPs. FB-PɛCL-NPs were prepared by solvent displacement method with poloxamer 188 (P188) as stabilizer. Freezing and primary drying (PD) were studied and optimized through freeze-thawing test and FD microscopy. Design of experiments was used to accurate secondary drying (SD) conditions and components concentration. Formulations were selected according to desired physicochemical properties. Furthermore, differential scanning calorimetry (DSC) and X-ray diffraction (XRD) were used to study interactions components. Optimized FB-PɛCL-NPs, stabilized with 3.5% (w/w) P188 and protected with 8% (w/w) poly(ethylene glycol), was submitted to precooling at +10 °C for 1 h, freezing at -50 °C for 4 h, PD at +5 °C and 0.140 mbar for 24 h and a SD at +45 °C during 10 h. These conditions showed 188.4 ± 1.3 nm, 0.087 ± 0.014, 85.5 ± 1.4%, 0.61 ± 0.12%, -16.4 ± 0.1 mV and 325 ± 7 mOsm/kg of average size, polydispersity index, entrapment efficiency, residual moisture, surface charge and osmolality, respectively. It performed a long-term stability >12 months. DSC and XRD spectra confirmed adequate chemical interaction between formulation components and showed a semi-crystalline state after FD. An optimal freeze dried ocular formulation was achieved. Evidently, the successful design of this promising colloidal system resulted from rational cooperation between a good formulation and the right conditions in the FD process.

  12. Design and optimization of a self-developing single axis tracking PV array

    International Nuclear Information System (INIS)

    Colozza, A.J.

    1992-01-01

    This paper reports on a study performed in order to design a tracking PV array and optimize the design for maximum specific power. The design considerations were minimal deployment time, high reliability and small stowage volume. The array design was self-deployable, from a compact stowage configuration, using a passive pressurized gas deployment mechanism. The array structural components consist of a combination of beams, columns and cables used to deploy and orient a flexible PV blanket. Each structural component of the design was analyzed to determine the size necessary to withstand the various forces it would be subjected to. An optimization was performed to determine the array dimensions and blanket geometry which produce the maximum specific power

  13. Contribution of social relationships to self-rated health among Japanese community-dwelling elderly.

    Science.gov (United States)

    Kawasaki, Ryoko; Nakao, Rieko; Ohnishi, Mayumi

    2018-05-01

    Objective: Participation in social activities is associated with physical and psychological health in the community-dwelling elderly population. We examined the two factors of social relations and community health resources, associated with higher self-rated health levels in the community-dwelling elderly. Methods: A total of 145 community-dwelling elderly people ≥ 65 years old from two neighborhood associations in Nagasaki City were recruited for this study, representing 85% of the officially registered ≥ 65-year-old population in the target area. Face-to-face interviews using a structured questionnaire were conducted by trained interviewers in August 2009, with questions related to sociodemographic characteristics, social relationships, and self-rated health (SRH). Community health resources (type and walking distance from home) were evaluated by one of the authors as a community assessment. Results: Seventy-eight community-dwelling elderly people (25 men and 53 women) participated in the study. Elderly people who reported going out every day were more likely to show higher SRH scores (excellent/good) than those going out less often (OR: 3.7; 95% confidence interval [CI]: 1.0, 14.2; P = 0.056). The numbers of interactions with friends in higher and lower SRH groups were 6.5 ± 8.4 (mean ± standard deviation) and 2.4 ± 1.1 ( P = 0.01, Mann-Whitney U test), respectively. The numbers of relatives talking on the phone in higher and lower SRH groups were 2.9 ± 1.3 and 2.2 ± 1.2 ( P = 0.031, Mann-Whitney U test), respectively. Meeting scores with friends in higher and lower SRH groups were 7.8 ± 5.8 and 4.5 ± 3.6 ( P = 0.068), respectively. The scores of community health resources among higher and lower SRH groups were 21.2 ± 1.5 and 20.9 ± 1.4 ( P = 0.547), respectively. The scores of community association/activities in higher and lower SRH groups were 3.9 ± 1.0 and 3.6 ± 0.9 ( P = 0.227), respectively. Conclusion: This study indicated the importance

  14. On the stability of the CO adsorption-induced and self-organized CuPt surface alloy

    DEFF Research Database (Denmark)

    Andersson, Klas Jerker; Chorkendorff, Ib

    2010-01-01

    The stability of the recently discovered CO-induced and self-organized CuPt surface alloy was explored at near ambient pressures of O-2 (200 mbar) at room temperature, in a CO + H-2 mix (P-tot = 220 mbar, 4% CO) from room temperature to 573 K, as well as in a CO + H2O mix (P-tot = 17 mbar, 50% CO...

  15. PID self tuning control based on Mamdani fuzzy logic control for quadrotor stabilization

    Energy Technology Data Exchange (ETDEWEB)

    Priyambodo, Tri Kuntoro, E-mail: mastri@ugm.ac.id; Putra, Agfianto Eko [Aerospace and Aeronautics Electronics Research Group, Universitas Gadjah Mada, Yogyakarta (Indonesia); Department of Computer Science and Electronics, Universitas Gadjah Mada, Yogyakarta (Indonesia); Dharmawan, Andi, E-mail: andi-dharmawan@ugm.ac.id [Department of Computer Science and Electronics, Universitas Gadjah Mada, Yogyakarta (Indonesia)

    2016-02-01

    Quadrotor as one type of UAV have the ability to perform Vertical Take Off and Landing (VTOL). It allows the Quadrotor to be stationary hovering in the air. PID (Proportional Integral Derivative) control system is one of the control methods that are commonly used. It is usually used to optimize the Quadrotor stabilization at least based on the three Eulerian angles (roll, pitch, and yaw) as input parameters for the control system. The three constants of PID can be obtained in various methods. The simplest method is tuning manually. This method has several weaknesses. For example if the three constants are not exact, the resulting response will deviate from the desired result. By combining the methods of PID with fuzzy logic systems where human expertise is implemented into the machine language is expected to further optimize the control system.

  16. A longitudinal study of the effects of premarital communication, relationship stability, and self-esteem on sexual satisfaction in the first year of marriage.

    Science.gov (United States)

    Larson, J H; Anderson, S M; Holman, T B; Niemann, B K

    1998-01-01

    This study examined select premarital factors from the ecosystemic perspective hypothesized to influence marital sexual satisfaction in the first year of marriage. A sample of 70 couples was administered by the Preparation of Marriage Questionnaire (PREP-M) a few months prior to marriage to measure premarital levels of empathy, self-disclosure, open communication, relationship stability, and self-esteem. At 1 year of marriage, their sexual satisfaction was assessed using the Index of Sexual Satisfaction (ISS). Using multiple regression analyses it was found that the best premarital predictors of husband's marital sexual satisfaction were wives' self-esteem, wives' open communication, and wives' relationship stability. The best predictors for wives' marital sexual satisfaction were wives' self-esteem, wives' open communication, and husbands' empathic communication. Conclusions and implications for premarital counselling and family life education are discussed.

  17. Propagation stability of self-reconstructing Bessel beams enables contrast-enhanced imaging in thick media.

    Science.gov (United States)

    Fahrbach, Florian O; Rohrbach, Alexander

    2012-01-17

    Laser beams that can self-reconstruct their initial beam profile even in the presence of massive phase perturbations are able to propagate deeper into inhomogeneous media. This ability has crucial advantages for light sheet-based microscopy in thick media, such as cell clusters, embryos, skin or brain tissue or plants, as well as scattering synthetic materials. A ring system around the central intensity maximum of a Bessel beam enables its self-reconstruction, but at the same time illuminates out-of-focus regions and deteriorates image contrast. Here we present a detection method that minimizes the negative effect of the ring system. The beam's propagation stability along one straight line enables the use of a confocal line principle, resulting in a significant increase in image contrast. The axial resolution could be improved by nearly 100% relative to the standard light-sheet techniques using scanned Gaussian beams, while demonstrating self-reconstruction also for high propagation depths.

  18. Improved Balance Confidence and Stability for Elderly After 6 Weeks of a Multimodal Self-Administered Balance-Enhancing Exercise Program

    Directory of Open Access Journals (Sweden)

    Anna Hafström MD, PhD

    2016-04-01

    Full Text Available Objective: To develop and assess the efficacy of a multimodal balance-enhancing exercise program (BEEP designed to be regularly self-administered by community-dwelling elderly. The program aims to promote sensory reweighting, facilitate motor control, improve gaze stabilization, and stimulate continuous improvement by being constantly challenging. Method: Forty participants aged 60 to 80 years performed 6 weeks of BEEP training, on average for 16 min four times weekly, in a randomized one-arm crossover design. Results: One-leg standing time improved 32% with eyes open (EO, 206% with eyes closed (EC on solid surface, and 54% EO on compliant surface ( p < .001. Posturography confirmed balance improvements when perturbed on solid and compliant surfaces with EO and EC ( p  ≤ .033. Walking, step stool, and Timed Up and Go speeds increased ( p  ≤ .001, as did scores in Berg Balance and balance confidence scales ( p  ≤ .018. Discussion: Multimodal balance exercises offer an efficient, cost-effective way to improve balance control and confidence in elderly.

  19. Tuning the Wettability of Halloysite Clay Nanotubes by Surface Carbonization for Optimal Emulsion Stabilization.

    Science.gov (United States)

    Owoseni, Olasehinde; Zhang, Yueheng; Su, Yang; He, Jibao; McPherson, Gary L; Bose, Arijit; John, Vijay T

    2015-12-29

    The carbonization of hydrophilic particle surfaces provides an effective route for tuning particle wettability in the preparation of particle-stabilized emulsions. The wettability of naturally occurring halloysite clay nanotubes (HNT) is successfully tuned by the selective carbonization of the negatively charged external HNT surface. The positively charge chitosan biopolymer binds to the negatively charged external HNT surface by electrostatic attraction and hydrogen bonding, yielding carbonized halloysite nanotubes (CHNT) on pyrolysis in an inert atmosphere. Relative to the native HNT, the oil emulsification ability of the CHNT at intermediate levels of carbonization is significantly enhanced due to the thermodynamically more favorable attachment of the particles at the oil-water interface. Cryogenic scanning electron microscopy (cryo-SEM) imaging reveals that networks of CHNT attach to the oil-water interface with the particles in a side-on orientation. The concepts advanced here can be extended to other inorganic solids and carbon sources for the optimal design of particle-stabilized emulsions.

  20. A proposal for self-correcting stabilizer quantum memories in 3 dimensions (or slightly less)

    Science.gov (United States)

    Brell, Courtney G.

    2016-01-01

    We propose a family of local CSS stabilizer codes as possible candidates for self-correcting quantum memories in 3D. The construction is inspired by the classical Ising model on a Sierpinski carpet fractal, which acts as a classical self-correcting memory. Our models are naturally defined on fractal subsets of a 4D hypercubic lattice with Hausdorff dimension less than 3. Though this does not imply that these models can be realized with local interactions in {{{R}}}3, we also discuss this possibility. The X and Z sectors of the code are dual to one another, and we show that there exists a finite temperature phase transition associated with each of these sectors, providing evidence that the system may robustly store quantum information at finite temperature.

  1. Pareto-Optimization of HTS CICC for High-Current Applications in Self-Field

    Directory of Open Access Journals (Sweden)

    Giordano Tomassetti

    2018-01-01

    Full Text Available The ENEA superconductivity laboratory developed a novel design for Cable-in-Conduit Conductors (CICCs comprised of stacks of 2nd-generation REBCO coated conductors. In its original version, the cable was made up of 150 HTS tapes distributed in five slots, twisted along an aluminum core. In this work, taking advantage of a 2D finite element model, able to estimate the cable’s current distribution in the cross-section, a multiobjective optimization procedure was implemented. The aim of optimization was to simultaneously maximize both engineering current density and total current flowing inside the tapes when operating in self-field, by varying the cross-section layout. Since the optimization process involved both integer and real geometrical variables, the choice of an evolutionary search algorithm was strictly necessary. The use of an evolutionary algorithm in the frame of a multiple objective optimization made it an obliged choice to numerically approach the problem using a nonstandard fast-converging optimization algorithm. By means of this algorithm, the Pareto frontiers for the different configurations were calculated, providing a powerful tool for the designer to achieve the desired preliminary operating conditions in terms of engineering current density and/or total current, depending on the specific application field, that is, power transmission cable and bus bar systems.

  2. A theoretical framework for a virtual diabetes self-management community intervention.

    Science.gov (United States)

    Vorderstrasse, Allison; Shaw, Ryan J; Blascovich, Jim; Johnson, Constance M

    2014-10-01

    Due to its high prevalence, chronic nature, potential complications, and self-management challenges for patients, diabetes presents significant health education and support issues. We developed and pilot-tested a virtual community for adults with type 2 diabetes to promote self-management education and provide social support. Although digital-based programs such as virtual environments can address significant barriers to reaching patients (i.e., child care, transportation, location), they must be strongly grounded in a theoretical basis to be well-developed and effective. In this article, we discuss how we synthesized behavioral and virtual environment theoretical frameworks to guide the development of SLIDES (Second Life Impacts Diabetes Education and Support). © The Author(s) 2014.

  3. Harmony as Ideology: Questioning the Diversity-Stability Hypothesis.

    Science.gov (United States)

    Nikisianis, Nikos; Stamou, Georgios P

    2016-03-01

    The representation of a complex but stable, self-regulated and, finally, harmonious nature penetrates the whole history of Ecology, thus contradicting the core of the Darwinian evolution. Originated in the pre-Darwinian Natural History, this representation defined theoretically the various schools of early ecology and, in the context of the cybernetic synthesis of the 1950s, it assumed a typical mathematical form on account of α positive correlation between species diversity and community stability. After 1960, these two aforementioned concepts and their positive correlation were proposed as environmental management tools, in the face of the ecological crisis arising at the time. In the early 1970s, and particularly after May's evolutionary arguments, the consensus around this positive correlation collapsed for a while, only to be promptly restored for the purpose of attaching an ecological value on biodiversity. In this paper, we explore the history of the diversity-stability hypothesis and we review the successive terms that have been used to express community stability. We argue that this hypothesis has been motivated by the nodal ideological presuppositions of order and harmony and that the scientific developments in this field largely correspond to external social pressures. We conclude that the conflict about the diversity-stability relationship is in fact an ideological debate, referring mostly to the way we see nature and society rather than to an autonomous scientific question. From this point of view, we may understand why Ecology's concepts and perceptions may decline and return again and again, forming a pluralistic scientific history.

  4. Optimization of drug loading to improve physical stability of paclitaxel-loaded long-circulating liposomes.

    Science.gov (United States)

    Kannan, Vinayagam; Balabathula, Pavan; Divi, Murali K; Thoma, Laura A; Wood, George C

    2015-01-01

    The effect of formulation and process parameters on drug loading and physical stability of paclitaxel-loaded long-circulating liposomes was evaluated. The liposomes were prepared by hydration-extrusion method. The formulation parameters such as total lipid content, cholesterol content, saturated-unsaturated lipid ratio, drug-lipid ratio and process parameters such as extrusion pressure and number of extrusion cycles were studied and their impact on drug loading and physical stability was evaluated. A proportionate increase in drug loading was observed with increase in the total phospholipid content. Cholesterol content and saturated lipid content in the bilayer showed a negative influence on drug loading. The short-term stability evaluation of liposomes prepared with different drug-lipid ratios demonstrated that 1:60 as the optimum drug-lipid ratio to achieve a loading of 1-1.3 mg/mL without the risk of physical instability. The vesicle size decreased with an increase in the extrusion pressure and number of extrusion cycles, but no significant trends were observed for drug loading with changes in process pressure or number of cycles. The optimization of formulation and process parameters led to a physically stable formulation of paclitaxel-loaded long-circulating liposomes that maintain size, charge and integrity during storage.

  5. The Evolution of Community Self-Organization in Interaction With Government Institutions: Cross-Case Insights From Three Countries

    NARCIS (Netherlands)

    J. Edelenbos (Jurian); I.F. van Meerkerk (Ingmar); Schenk, T. (Todd)

    2018-01-01

    textabstractThis article deals with the evolution of community self-organization in public administration. Within the literature of interactive governance, increasing attention is being paid to how communities take initiative in dealing with societal issues. However, we know little about the factors

  6. Individual differences in reactivity to daily events: examining the roles of stability and level of self-esteem.

    Science.gov (United States)

    Greenier, K D; Kernis, M H; McNamara, C W; Waschull, S B; Berry, A J; Herlocker, C E; Abend, T A

    1999-02-01

    Unstable self-esteem is thought to reflect fragile and vulnerable feelings of self-worth that are affected by specific positive and negative events. Direct evidence for this contention is lacking, however. To redress this situation, we examined the extent to which level and stability of self-esteem predicted the impact that everyday positive and negative events had on individuals' feelings about themselves. Participants recorded the most positive and most negative event that occurred each day Monday through Thursday for a period of 2 weeks. They then indicated the extent to which each event made them feel better or worse about themselves. As anticipated, negative and positive events had a greater impact on the self-feelings of individuals with unstable as opposed to stable self-esteem (although the effect for positive events was marginal). Additional findings indicated that event qualities (i.e., self-esteem relevance and concerns about social acceptance/rejection) could account for the unstable self-esteem/greater reactivity link for negative events, but not for positive events. Negative, but not positive, events had a greater impact on the self-feelings of individuals with low as compared to high levels of self-esteem. Theoretical implications are discussed.

  7. Longitudinal Examination of Optimism, Personal Self-Efficacy and Student Well-Being: A Path Analysis

    Science.gov (United States)

    Phan, Huy P.

    2016-01-01

    The present longitudinal study, based on existing theoretical tenets, explored a conceptual model that depicted four major orientations: optimism, self-efficacy, and academic well-being. An important question for consideration, in this case, involved the testing of different untested trajectories that could explain and predict individuals'…

  8. SECOND-ORDER VARIATIONAL ANALYSIS IN CONIC PROGRAMMING WITH APPLICATIONS TO OPTIMALITY AND STABILITY

    Czech Academy of Sciences Publication Activity Database

    Mordukhovich, B. S.; Outrata, Jiří; Ramírez, H. C.

    2015-01-01

    Roč. 25, č. 1 (2015), s. 76-101 ISSN 1052-6234 R&D Projects: GA ČR(CZ) GAP201/12/0671 Grant - others:Australian Research Council(AU) DP-110102011; USA National Science Foundation(US) DMS-1007132; Australian Reseach Council(AU) DP-12092508; Portuguese Foundation of Science and Technologies(PT) MAT/11109; FONDECYT Project(CL) 1110888; Universidad de Chile(CL) BASAL Project Centro de Modelamiento Matematico Institutional support: RVO:67985556 Keywords : variational analysis * second-order theory * conic programming * generalized differentiation * optimality conditions * isolated calmness * tilt stability Subject RIV: BA - General Mathematics Impact factor: 2.659, year: 2015 http://library.utia.cas.cz/separaty/2015/MTR/outrata-0439413.pdf

  9. Tensegrity structures form, stability, and symmetry

    CERN Document Server

    Zhang, Jing Yao

    2015-01-01

    To facilitate a deeper understanding of tensegrity structures, this book focuses on their two key design problems: self-equilibrium analysis and stability investigation. In particular, high symmetry properties of the structures are extensively utilized. Conditions for self-equilibrium as well as super-stability of tensegrity structures are presented in detail. An analytical method and an efficient numerical method are given for self-equilibrium analysis of tensegrity structures: the analytical method deals with symmetric structures and the numerical method guarantees super-stability. Utilizing group representation theory, the text further provides analytical super-stability conditions for the structures that are of dihedral as well as tetrahedral symmetry. This book not only serves as a reference for engineers and scientists but is also a useful source for upper-level undergraduate and graduate students. Keeping this objective in mind, the presentation of the book is self-contained and detailed, with an abund...

  10. An Investigation of the Construct Validity of the Personality Trait of Self-Directed Learning

    Science.gov (United States)

    Lounsbury, John W.; Levy, Levy J.; Park, Soo-Hee; Gibson, Lucy W.; Smith, Ryan

    2009-01-01

    Based on samples of 398 middle school students, 568 high school students, and 1159 college students, self-directed learning was found to be related to cumulative grade-point-average at all levels as well as to Big Five personality traits (Openness, Conscientiousness, Emotional Stability, and Extraversion), narrow personality traits (Optimism,…

  11. From ring-in-ring to sphere-in-sphere: self-assembly of discrete 2D and 3D architectures with increasing stability.

    Science.gov (United States)

    Sun, Bin; Wang, Ming; Lou, Zhichao; Huang, Mingjun; Xu, Chenglong; Li, Xiaohong; Chen, Li-Jun; Yu, Yihua; Davis, Grant L; Xu, Bingqian; Yang, Hai-Bo; Li, Xiaopeng

    2015-02-04

    Directed by increasing the density of coordination sites (DOCS) to increase the stability of assemblies, discrete 2D ring-in-rings and 3D sphere-in-sphere were designed and self-assembled by one tetratopic pyridyl-based ligand with 180° diplatinum(II) acceptors and naked Pd(II), respectively. The high DOCS resulted by multitopic ligand provided more geometric constraints to form discrete structures with high stability. Compared to reported supramolecular hexagons and polyhedra by ditotpic ligands, the self-assembly of such giant architectures using multitopic ligands with all rigid backbone emphasized the structural integrity with precise preorganization of entire architecture, and required elaborate synthetic operations for ligand preparation. In-depth structural characterization was conducted to support desired structures, including multinuclear NMR ((1)H, (31)P, and (13)C) analysis, 2D NMR spectroscopy (COSY and NOESY), diffusion-ordered NMR spectroscopy (DOSY), multidimensional mass spectrometry, TEM and AFM. Furthermore, a quantitative definition of DOCS was proposed to compare 2D and 3D structures and correlate the DOCS and stability of assemblies in a quantitative manner. Finally, ring-in-rings in DMSO or DMF could undergo hierarchical self-assembly into the ordered nanostructures and generated translucent supramolecular metallogels.

  12. Self-Regulatory Strategies in Daily Life: Selection, Optimization, and Compensation and Everyday Memory Problems

    Science.gov (United States)

    Robinson, Stephanie A.; Rickenbach, Elizabeth H.; Lachman, Margie E.

    2016-01-01

    The effective use of self-regulatory strategies, such as selection, optimization, and compensation (SOC) requires resources. However, it is theorized that SOC use is most advantageous for those experiencing losses and diminishing resources. The present study explored this seeming paradox within the context of limitations or constraints due to…

  13. An optimization of robust SMES with specified structure H∞ controller for power system stabilization considering superconducting magnetic coil size

    International Nuclear Information System (INIS)

    Ngamroo, Issarachai

    2011-01-01

    Even the superconducting magnetic energy storage (SMES) is the smart stabilizing device in electric power systems, the installation cost of SMES is very high. Especially, the superconducting magnetic coil size which is the critical part of SMES, must be well designed. On the contrary, various system operating conditions result in system uncertainties. The power controller of SMES designed without taking such uncertainties into account, may fail to stabilize the system. By considering both coil size and system uncertainties, this paper copes with the optimization of robust SMES controller. No need of exact mathematic equations, the normalized coprime factorization is applied to model system uncertainties. Based on the normalized integral square error index of inter-area rotor angle difference and specified structured H ∞ loop shaping optimization, the robust SMES controller with the smallest coil size, can be achieved by the genetic algorithm. The robustness of the proposed SMES with the smallest coil size can be confirmed by simulation study.

  14. Effect of professional self-concept on burnout among community health nurses in Chengdu, China: the mediator role of organisational commitment.

    Science.gov (United States)

    Cao, Xiaoyi; Chen, Lin; Tian, Lang; Diao, Yongshu; Hu, Xiuying

    2015-10-01

    To examine the associations among professional self-concept, organisational commitment and burnout, and to analyse the mediating role of organisational commitment on the relationship between professional self-concept and burnout among community health nurses in Chengdu, China. Previous studies have focused on work environmental variables that contributed to burnout in nurses. However, no study has explored the mediating effect of organisational commitment on the correlation between professional self-concept and burnout in community health nurses. A cross-sectional descriptive study. This study was conducted at 36 community health centres in Chengdu, China with 485 nurses sampled using a two-stage sampling method. The measures used in our study included Nurses' Self-concept Questionnaire, Organisational Commitment Scale and Maslach Burnout Inventory. The results of structural equation model techniques indicated that, in the direct approach, positive professional self-concept resulted in increased organisational commitment and reduced burnout. Higher organisational commitment resulted in less burnout. In the indirect approach, organisational commitment performed as a partial mediator on the correlation between professional self-concept and burnout. Positive perception of professional self-concept can result in reduced burnout via enhancing organisational commitment. It is crucial for nursing administrators to develop effective intervention strategies such as skills escalator training and assertive training, and establishing a supportive working environment to enhance nurses' professional self-concept and organisational commitment, and decrease burnout. © 2015 John Wiley & Sons Ltd.

  15. Modelling and Optimal Control of Typhoid Fever Disease with Cost-Effective Strategies.

    Science.gov (United States)

    Tilahun, Getachew Teshome; Makinde, Oluwole Daniel; Malonza, David

    2017-01-01

    We propose and analyze a compartmental nonlinear deterministic mathematical model for the typhoid fever outbreak and optimal control strategies in a community with varying population. The model is studied qualitatively using stability theory of differential equations and the basic reproductive number that represents the epidemic indicator is obtained from the largest eigenvalue of the next-generation matrix. Both local and global asymptotic stability conditions for disease-free and endemic equilibria are determined. The model exhibits a forward transcritical bifurcation and the sensitivity analysis is performed. The optimal control problem is designed by applying Pontryagin maximum principle with three control strategies, namely, the prevention strategy through sanitation, proper hygiene, and vaccination; the treatment strategy through application of appropriate medicine; and the screening of the carriers. The cost functional accounts for the cost involved in prevention, screening, and treatment together with the total number of the infected persons averted. Numerical results for the typhoid outbreak dynamics and its optimal control revealed that a combination of prevention and treatment is the best cost-effective strategy to eradicate the disease.

  16. Do ecohydrology and community dynamics feed back to banded-ecosystem structure and productivity?

    Science.gov (United States)

    Callegaro, Chiara; Ursino, Nadia

    2016-04-01

    Mixed communities including grass, shrubs and trees are often reported to populate self-organized vegetation patterns. Patterns of survey data suggest that species diversity and complementarity strengthen the dynamics of banded environments. Resource scarcity and local facilitation trigger self organization, whereas coexistence of multiple species in vegetated self-organizing patches, implying competition for water and nutrients and favorable reproduction sites, is made possible by differing adaptation strategies. Mixed community spatial self-organization has so far received relatively little attention, compared with local net facilitation of isolated species. We assumed that soil moisture availability is a proxy for the environmental niche of plant species according to Ursino and Callegaro (2016). Our modelling effort was focused on niche differentiation of coexisting species within a tiger bush type ecosystem. By minimal numerical modelling and stability analysis we try to answer a few open scientific questions: Is there an adaptation strategy that increases biodiversity and ecosystem functioning? Does specific adaptation to environmental niches influence the structure of self-organizing vegetation pattern? What specific niche distribution along the environmental gradient gives the highest global productivity?

  17. Spirituality and optimism: a holistic approach to component-based, self-management treatment for HIV.

    Science.gov (United States)

    Brown, Jordan; Hanson, Jan E; Schmotzer, Brian; Webel, Allison R

    2014-10-01

    For people living with HIV (PLWH), spirituality and optimism have a positive influence on their health, can slow HIV disease progression, and can improve quality of life. Our aim was to describe longitudinal changes in spirituality and optimism after participation in the SystemCHANGE™-HIV intervention. Upon completion of the intervention, participants experienced an 11.5 point increase in overall spiritual well-being (p = 0.036), a 6.3 point increase in religious well-being (p = 0.030), a 4.8 point increase in existential well-being (p = 0.125), and a 0.8 point increase in total optimism (p = 0.268) relative to controls. Our data suggest a group-based self-management intervention increases spiritual well-being in PLWH.

  18. Multi-objective optimization problems concepts and self-adaptive parameters with mathematical and engineering applications

    CERN Document Server

    Lobato, Fran Sérgio

    2017-01-01

    This book is aimed at undergraduate and graduate students in applied mathematics or computer science, as a tool for solving real-world design problems. The present work covers fundamentals in multi-objective optimization and applications in mathematical and engineering system design using a new optimization strategy, namely the Self-Adaptive Multi-objective Optimization Differential Evolution (SA-MODE) algorithm. This strategy is proposed in order to reduce the number of evaluations of the objective function through dynamic update of canonical Differential Evolution parameters (population size, crossover probability and perturbation rate). The methodology is applied to solve mathematical functions considering test cases from the literature and various engineering systems design, such as cantilevered beam design, biochemical reactor, crystallization process, machine tool spindle design, rotary dryer design, among others.

  19. Self-stabilizing Synchronization in Mobile Sensor Networks with Covering

    Science.gov (United States)

    Beauquier, Joffroy; Burman, Janna

    Synchronization is widely considered as an important service in distributed systems which may simplify protocol design. Phase clock is a general synchronization tool that provides a form of a logical time. This paper presents a self-stabilizing (a tolerating state-corrupting transient faults) phase clock algorithm suited to the model of population protocols with covering. This model has been proposed recently for sensor networks with a very large, possibly unknown number of anonymous mobile agents having small memory. Agents interact in pairs in an asynchronous way subject to the constraints expressed in terms of the cover times of agents. The cover time expresses the "frequency" of an agent to communicate with all the others and abstracts agent's communication characteristics (e.g. moving speed/patterns, transmitting/receiving capabilities). We show that a phase clock is impossible in the model with only constant-state agents. Hence, we assume an existence of resource-unlimited agent - the base station.

  20. Factors influencing the current practice of self-medication consultations in Eastern Indonesian community pharmacies: a qualitative study.

    Science.gov (United States)

    Brata, Cecilia; Fisher, Colleen; Marjadi, Brahmaputra; Schneider, Carl R; Clifford, Rhonda M

    2016-05-13

    Research has shown that the current practice of pharmacy staff when providing self-medication consultations in Indonesia is suboptimal. To improve the performance of pharmacy staff when providing self-medication consultations in community pharmacies, the factors that influence current practice need to be understood. The aim of this study is to identify the factors that influence current practice of pharmacy staff when handling self-medication consultations in Eastern Indonesian community pharmacies. Fifteen in-depth interviews were conducted with pharmacists, pharmacy technicians, pharmacy owners, and counter attendants. Thematic analysis was used to generate findings. The current practice of pharmacy staff when handling self-medication consultations is directly influenced by the professionalism of pharmacy staff and patient responses to the consultations. These factors are in turn affected by the organisational context of the pharmacy and the external pharmacy environment. The organisational context of the pharmacy includes staffing, staff affordability, and the availability of time and facilities in which to provide consultations. The external pharmacy environment includes the number of trained pharmacy staff in the research setting, the relevance of pharmacy education to the needs of pharmacy practice, the support offered by the Indonesian Pharmacists Association, a competitive business environment, and the policy environment. Complex and inter-related factors influence the current practice of pharmacy staff when providing self-medication consultations in community pharmacies in this research setting. Multiple strategies will be required to improve consultation practices.

  1. The Relationship between Elementary Teachers' Perceived Self-Efficacy and Principals' Facilitation of Professional Learning Communities

    Science.gov (United States)

    Mathews, Tracy A.

    2017-01-01

    This quantitative correlation survey study investigated the relationship between teachers' perceptions of the effectiveness of school principals as instructional leaders in professional learning communities (PLCs) and self-efficacy beliefs of teachers. Social Cognitive Theory, self-efficacy concept, and Adult Learning Theory were at the core of…

  2. Elder women's perceptions around optimal perinatal health: a constructivist grounded-theory study with an Indigenous community in southern Ontario.

    Science.gov (United States)

    Kandasamy, Sujane; Vanstone, Meredith; Oremus, Mark; Hill, Trista; Wahi, Gita; Wilson, Julie; Davis, A Darlene; Jacobs, Ruby; Anglin, Rebecca; Anand, Sonia Savitri

    2017-05-18

    Women play important roles in translating health knowledge, particularly around pregnancy and birth, in Indigenous societies. We investigated elder Indigenous women's perceptions around optimal perinatal health. Using a methodological framework that integrated a constructivist grounded-theory approach with an Indigenous epistemology, we conducted and analyzed in-depth interviews and focus groups with women from the Six Nations community in southern Ontario who self-identified as grandmothers. Our purposive sampling strategy was guided by a Six Nations advisory group and included researcher participation in a variety of local gatherings as well as personalized invitations to specific women, either face-to-face or via telephone. Three focus groups and 7 individual interviews were conducted with 18 grandmothers. The participants' experiences converged on 3 primary beliefs: pregnancy is a natural phase, pregnancy is a sacred period for the woman and the unborn child, and the requirements of immunity, security (trust), comfort, social development and parental responsibility are necessary for optimal postnatal health. Participants also identified 6 communal responsibilities necessary for families to raise healthy children: access to healthy and safe food, assurance of strong social support networks for mothers, access to resources for postnatal support, increased opportunities for children to participate in physical activity, more teachings around the impact of maternal behaviours during pregnancy and more teachings around spirituality/positive thinking. We also worked with the Six Nations community on several integrated knowledge-translation elements, including collaboration with an Indigenous artist to develop a digital story (short film). Elder women are a trusted and knowledgeable group who are able to understand and incorporate multiple sources of knowledge and deliver it in culturally meaningful ways. Thus, tailoring public health programming to include elder women

  3. Self-consistent study of nuclei far from stability with the energy density method

    CERN Document Server

    Tondeur, F

    1981-01-01

    The self-consistent energy density method has been shown to give good results with a small number of parameters for the calculation of nuclear masses, radii, deformations, neutron skins, shell and sub- shell effects. It is here used to study the properties of nuclei far from stability, like densities, shell structure, even-odd mass differences, single-particle potentials and nuclear deformations. A few possible consequences of the results for astrophysical problems are briefly considered. The predictions of the model in the super- heavy region are summarised. (34 refs).

  4. Quality assessment of patients’ self-monitoring of blood glucose in community pharmacies

    Directory of Open Access Journals (Sweden)

    Kjome RL

    2010-03-01

    Full Text Available Objective: To evaluate diabetes patients’ self-monitoring of blood glucose using a community pharmacy-based quality assurance procedure, to investigate whether the procedure improved the quality of the patient performance of self monitoring of blood glucose, and to examine the opinions of the patients taking part in the study. Methods: The results of patient blood glucose measurements were compared to the results obtained with HemoCue Glucose 201+ by pharmacy employees in 16 Norwegian community pharmacies. Patient performance was monitored using an eight item checklist. Patients whose blood glucose measurements differed from pharmacy measurements by more than 20% were instructed in the correct use of their glucometer. The patients then re-measured their blood glucose. If the results were still outside the set limits, the control procedure was repeated with a new lot of glucometer strips, and then with a new glucometer. The patients returned for a follow-up visit after three months. Results: During the first visit, 5% of the 338 patients had measurements that deviated from pharmacy blood glucose values by more than 20% and user errors were observed for 50% of the patients. At the second visit, there was no significant change in the analytical quality of patient measurements, but the percentage of patients who made user errors had decreased to 29% (p < 0.001. Eighty-five percent of the patients reported that they used their blood glucose results to adjust medication, exercise or meals. Fifty-one percent of the patients reported a greater trust in their measurements after the second visit. Eighty percent of patients wished to have their measurements assessed yearly. Of these patients, 83% preferred to have the assessment done at the community pharmacy. Conclusion: A community pharmacy-based quality assessment procedure of patients’ self monitoring of blood glucose significantly reduced the number of user errors. The analytical quality of the

  5. Analyzing Reflections in Service Learning to Promote Personal Growth and Community Self-Efficacy

    Science.gov (United States)

    Sanders, Martha J.; Van Oss, Tracy; McGeary, Signian

    2016-01-01

    The use of structured reflections for promoting personal understanding and community self-efficacy was examined in 65 occupational therapy college students in a service learning course. Students in the experimental group wrote structured reflections throughout the semester while students in the control groups used non-structured reflections.…

  6. Community Program Improves Quality of Life and Self-Management in Older Adults with Diabetes Mellitus and Comorbidity.

    Science.gov (United States)

    Markle-Reid, Maureen; Ploeg, Jenny; Fraser, Kimberly D; Fisher, Kathryn A; Bartholomew, Amy; Griffith, Lauren E; Miklavcic, John; Gafni, Amiram; Thabane, Lehana; Upshur, Ross

    2018-02-01

    To compare the effect of a 6-month community-based intervention with that of usual care on quality of life, depressive symptoms, anxiety, self-efficacy, self-management, and healthcare costs in older adults with type 2 diabetes mellitus (T2DM) and 2 or more comorbidities. Multisite, single-blind, parallel, pragmatic, randomized controlled trial. Four communities in Ontario, Canada. Community-dwelling older adults (≥65) with T2DM and 2 or more comorbidities randomized into intervention (n = 80) and control (n = 79) groups (N = 159). Client-driven, customized self-management program with up to 3 in-home visits from a registered nurse or registered dietitian, a monthly group wellness program, monthly provider team case conferences, and care coordination and system navigation. Quality-of-life measures included the Physical Component Summary (PCS, primary outcome) and Mental Component Summary (MCS, secondary outcome) scores of the Medical Outcomes Study 12-item Short-Form Health Survey (SF-12). Other secondary outcome measures were the Generalized Anxiety Disorder Scale, Center for Epidemiologic Studies Depression Scale (CES-D-10), Summary of Diabetes Self-Care Activities (SDSCA), Self-Efficacy for Managing Chronic Disease, and healthcare costs. Morbidity burden was high (average of eight comorbidities). Intention-to-treat analyses using analysis of covariance showed a group difference favoring the intervention for the MCS (mean difference = 2.68, 95% confidence interval (CI) = 0.28-5.09, P = .03), SDSCA (mean difference = 3.79, 95% CI = 1.02-6.56, P = .01), and CES-D-10 (mean difference = -1.45, 95% CI = -0.13 to -2.76, P = .03). No group differences were seen in PCS score, anxiety, self-efficacy, or total healthcare costs. Participation in a 6-month community-based intervention improved quality of life and self-management and reduced depressive symptoms in older adults with T2DM and comorbidity without increasing total healthcare costs.

  7. Making it local: Beacon Communities use health information technology to optimize care management.

    Science.gov (United States)

    Allen, Amy; Des Jardins, Terrisca R; Heider, Arvela; Kanger, Chatrian R; Lobach, David F; McWilliams, Lee; Polello, Jennifer M; Rein, Alison L; Schachter, Abigail A; Singh, Ranjit; Sorondo, Barbara; Tulikangas, Megan C; Turske, Scott A

    2014-06-01

    Care management aims to provide cost-effective, coordinated, non-duplicative care to improve care quality, population health, and reduce costs. The 17 communities receiving funding from the Office of the National Coordinator for Health Information Technology through the Beacon Community Cooperative Agreement Program are leaders in building and strengthening their health information technology (health IT) infrastructure to provide more effective and efficient care management. This article profiles 6 Beacon Communities' health IT-enabled care management programs, highlighting the influence of local context on program strategy and design, and describing challenges, lessons learned, and policy implications for care delivery and payment reform. The unique needs (eg, disease burden, demographics), community partnerships, and existing resources and infrastructure all exerted significant influence on the overall priorities and design of each community's care management program. Though each Beacon Community needed to engage in a similar set of care management tasks--including patient identification, stratification, and prioritization; intervention; patient engagement; and evaluation--the contextual factors helped shape the specific strategies and tools used to carry out these tasks and achieve their objectives. Although providers across the country are striving to deliver standardized, high-quality care, the diverse contexts in which this care is delivered significantly influence the priorities, strategies, and design of community-based care management interventions. Gaps and challenges in implementing effective community-based care management programs include: optimizing allocation of care management services; lack of available technology tailored to care management needs; lack of standards and interoperability; integrating care management into care settings; evaluating impact; and funding and sustainability.

  8. A generic methodology for the optimisation of sewer systems using stochastic programming and self-optimizing control

    DEFF Research Database (Denmark)

    Maurico-Iglesias, Miguel; Castro, Ignacio Montero; Mollerup, Ane Loft

    2015-01-01

    . Such controller is aimed at keeping the system close to the optimal performance, thanks to an optimal selection of controlled variables. The definition of an optimal performance was carried out by a two-stage optimisation (stochastic and deterministic) to take into account both the overflow during the current......The design of sewer system control is a complex task given the large size of the sewer networks, the transient dynamics of the water flow and the stochastic nature of rainfall. This contribution presents a generic methodology for the design of a self-optimising controller in sewer systems...

  9. Depressive Symptoms and Deliberate Self-Harm in a Community Sample of Adolescents: A Prospective Study

    Directory of Open Access Journals (Sweden)

    Lars-Gunnar Lundh

    2011-01-01

    Full Text Available The associations between depressive symptoms and deliberate self-harm were studied by means of a 2-wave longitudinal design in a community sample of 1052 young adolescents, with longitudinal data for 83.6% of the sample. Evidence was found for a bidirectional relationship in girls, with depressive symptoms being a risk factor for increased self-harm one year later and self-harm a risk factor for increased depressive symptoms. Cluster analysis of profiles of depressive symptoms led to the identification of two clusters with clear depressive profiles (one severe, the other mild/moderate which were both characterized by an overrepresentation of girls and elevated levels of self-harm. Clusters with more circumscribed problems were also identified; of these, significantly increased levels of self-harm were found in a cluster characterized by negative self-image and in a cluster characterized by dysphoric relations to parents. It is suggested that self-harm serves more to regulate negative self-related feelings than sadness.

  10. Scale up, optimization and stability analysis of Curcumin C3 complex-loaded nanoparticles for cancer therapy

    Science.gov (United States)

    2012-01-01

    Background Nanoparticle based delivery of anticancer drugs have been widely investigated. However, a very important process for Research & Development in any pharmaceutical industry is scaling nanoparticle formulation techniques so as to produce large batches for preclinical and clinical trials. This process is not only critical but also difficult as it involves various formulation parameters to be modulated all in the same process. Methods In our present study, we formulated curcumin loaded poly (lactic acid-co-glycolic acid) nanoparticles (PLGA-CURC). This improved the bioavailability of curcumin, a potent natural anticancer drug, making it suitable for cancer therapy. Post formulation, we optimized our process by Reponse Surface Methodology (RSM) using Central Composite Design (CCD) and scaled up the formulation process in four stages with final scale-up process yielding 5 g of curcumin loaded nanoparticles within the laboratory setup. The nanoparticles formed after scale-up process were characterized for particle size, drug loading and encapsulation efficiency, surface morphology, in vitro release kinetics and pharmacokinetics. Stability analysis and gamma sterilization were also carried out. Results Results revealed that that process scale-up is being mastered for elaboration to 5 g level. The mean nanoparticle size of the scaled up batch was found to be 158.5 ± 9.8 nm and the drug loading was determined to be 10.32 ± 1.4%. The in vitro release study illustrated a slow sustained release corresponding to 75% drug over a period of 10 days. The pharmacokinetic profile of PLGA-CURC in rats following i.v. administration showed two compartmental model with the area under the curve (AUC0-∞) being 6.139 mg/L h. Gamma sterilization showed no significant change in the particle size or drug loading of the nanoparticles. Stability analysis revealed long term physiochemical stability of the PLGA-CURC formulation. Conclusions A successful effort towards

  11. Understanding the environmental issues in diabetes self-management education research: a reexamination of 8 studies in community-based settings.

    Science.gov (United States)

    Jack, Leonard; Liburd, Leandris; Spencer, Tirzah; Airhihenbuwa, Collins O

    2004-06-01

    Eight studies included in a recent systematic review of the efficacy of diabetes self-management education were qualitatively reexamined to determine the presence of theoretical frameworks, methods used to ensure cultural appropriateness, and the quality of the instrument. Theoretical frameworks that help to explain complex pathways that produce health outcomes were lacking; culture indices were not incorporated into diabetes self-management education; and the instruments used to measure outcomes were inadequate. We provide recommendations to improve research on diabetes self-management education in community settings through use of a contextual framework that encourages targeting multiple levels of influence--individual, family, organizational, community, and policy.

  12. Self-Stabilizing Measurement of Phase

    Science.gov (United States)

    Vinjanampathy, Sai

    2014-05-01

    Measuring phase accurately constitutes one of the most important task in precision measurement science. Such measurements can be deployed to measure everything from fundamental constants to measuring detuning and tunneling rates of atoms more precisely. Quantum mechanics enhances the ultimate bounds on the precision of such measurements possible, and exploit coherence and entanglement to reduce the phase uncertainty. In this work, we will describe a method to stabilize a decohering two-level atom and use the stabilizing measurements to learn the unknown phase acquired by the atom. Such measurements will employ a Bayesian learner to do active feedback control on the atom. We will discuss some ultimate bounds employed in precision metrology and an experimental proposal for the implementation of this scheme. Financial support from Ministry of Education, Singapore.

  13. Single-mode Brillouin fiber laser passively stabilized at resonance frequency with self-injection locked pump laser

    International Nuclear Information System (INIS)

    Spirin, V V; Lopez-Mercado, C A; Megret, P; Fotiadi, A A

    2012-01-01

    We demonstrate a single-mode Brillouin fiber ring laser, which is passively stabilized at pump resonance frequency by using self-injection locking of semiconductor pump laser. Resonance condition for Stokes radiation is achieved by length fitting of Brillouin laser cavity. The laser generate single-frequency Stokes wave with linewidth less than 0.5 kHz using approximately 17-m length cavity

  14. Solvability, regularity, and optimal control of boundary value problems for pdes in honour of Prof. Gianni Gilardi

    CERN Document Server

    Favini, Angelo; Rocca, Elisabetta; Schimperna, Giulio; Sprekels, Jürgen

    2017-01-01

    This volume gathers contributions in the field of partial differential equations, with a focus on mathematical models in phase transitions, complex fluids and thermomechanics. These contributions are dedicated to Professor Gianni Gilardi on the occasion of his 70th birthday. It particularly develops the following thematic areas: nonlinear dynamic and stationary equations; well-posedness of initial and boundary value problems for systems of PDEs; regularity properties for the solutions; optimal control problems and optimality conditions; feedback stabilization and stability results. Most of the articles are presented in a self-contained manner, and describe new achievements and/or the state of the art in their line of research, providing interested readers with an overview of recent advances and future research directions in PDEs.

  15. Attenuated psychosis and basic self-disturbance as risk factors for depression and suicidal ideation/behaviour in community-dwelling adolescents

    DEFF Research Database (Denmark)

    Koren, Dan; Rothschild-Yakar, Lily; Lacoua, Liza

    2017-01-01

    ), an established marker for CHR, and suicidality/self-harm in this population. The goal of this pilot study was to assess the association between SD, depression and suicidal ideation and behaviour among non-help-seeking adolescents from the community. METHOD: A total of 100 community-dwelling adolescents (age...... to derive a binary diagnosis of unipolar depression, as well as to measure suicidal ideation and behaviour and self-harm. RESULTS: In a multiple regression analysis, SD accounted for variance in depressive symptoms and suicidality/self-harm over and above that accounted for by APS. Moreover, SD accounted...... for variance in suicidality/self-harm over and above that accounted for by depression symptoms. CONCLUSIONS: These pilot results suggest that SD might be a unique dimension of vulnerability to depression and suicidality/self-harm in adolescence. Also, they encourage assessment of SD as part of a suicide risk...

  16. Emergency Department Utilization and Self-Reported Symptoms in Community-Dwelling Older Adults

    Science.gov (United States)

    Sawyer, Patricia; Kennedy, Richard; Williams, Courtney; Brown, Cynthia J.

    2016-01-01

    Background The rise in emergency department (ED) utilization among older adults is a nursing concern, because emergency nurses are uniquely positioned to positively impact the care of older adults. Symptoms have been associated with ED utilization, however, it remains unclear if symptoms are the primary reason for ED utilization. Purpose Describe the self-reported symptoms of community-dwelling older adults prior to accessing the emergency department. Examine the differences in self-reported symptoms among those who utilized the emergency department, and those who did not. Procedures A prospective longitudinal design was used. The sample included 403 community-dwelling older adults 75 years and older. Baseline in-home interviews were conducted followed by monthly telephone interviews over 15 months. Main Findings Commonly reported symptoms at baseline included pain, feeling tired, and having shortness of breath. In univariate analysis, pain, shortness of breath, fair/poor well-being, and feeling tired were significantly correlated with ED utilization. In multivariable models, problems with balance, and fair/poor well-being were significantly associated with ED utilization. Conclusions Several symptoms were common among this cohort of older adults. However, there were no significant differences in the types of symptoms reported by older adults who utilized the emergency department compared to those who did not use the emergency department. Based on these findings, symptoms among community-dwelling older adults may not be the primary reason for ED utilization. PMID:28131350

  17. Optimal stabilization of Boolean networks through collective influence

    Science.gov (United States)

    Wang, Jiannan; Pei, Sen; Wei, Wei; Feng, Xiangnan; Zheng, Zhiming

    2018-03-01

    Boolean networks have attracted much attention due to their wide applications in describing dynamics of biological systems. During past decades, much effort has been invested in unveiling how network structure and update rules affect the stability of Boolean networks. In this paper, we aim to identify and control a minimal set of influential nodes that is capable of stabilizing an unstable Boolean network. For locally treelike Boolean networks with biased truth tables, we propose a greedy algorithm to identify influential nodes in Boolean networks by minimizing the largest eigenvalue of a modified nonbacktracking matrix. We test the performance of the proposed collective influence algorithm on four different networks. Results show that the collective influence algorithm can stabilize each network with a smaller set of nodes compared with other heuristic algorithms. Our work provides a new insight into the mechanism that determines the stability of Boolean networks, which may find applications in identifying virulence genes that lead to serious diseases.

  18. Variability after 15 Years of Vegetation Recovery in Natural Secondary Forest with Timber Harvesting at Different Intensities in Southeastern China: Community Diversity and Stability

    Directory of Open Access Journals (Sweden)

    Zhilong Wu

    2018-01-01

    Full Text Available The mixed Cunninghamia lanceolata (Lamb. Hook., Pinus massoniana Lamb., and hardwood forest in southeastern China is a major assemblage in natural secondary forests, and of national and international importance in terms of both timber and ecosystem services. However, over-harvesting has threatened its long-term sustainability, and there is a knowledge gap relating to the effect of harvesting on the ecosystem. After conifer species were selected for harvesting, the mixed Chinese fir, pine, and hardwood forest was changed into mixed evergreen broadleaf forest. In this context, we observed the restoration dynamics of plant communities over a period of 15 years (1996 to 2011 with different levels of harvesting intensity, including selective harvesting at low (13.0% removal of growing stock volume, medium (29.1%, high (45.8%, and extra-high (67.1% intensities, as well as clear-cut harvesting (100.0%, with non-harvesting as the control, based on permanent sample plots established in a randomized block design in these forests in southeastern China. The impact on the richness, diversity, and evenness of plant species derived from descriptive statistical analyses was shown to initially increase, and then decrease, with an increase in harvesting intensity. The most critical impacts were on the richness, diversity, and evenness of shrub and herb species. Richness, diversity, and evenness of plant species recovered and increased under selective harvesting at low and medium intensities, while these parameters had not recovered and significantly decreased under selective harvesting at high and extra-high intensities, as well as with clear-cut harvesting. The impact on the plant community stability was derived from the stability test method of the improved Godron M. The plant community stability was closest to the point of stability (20/80 under selective harvesting at medium intensity, followed by selective harvesting at low intensity. The plant community

  19. Self-organization towards optimally interdependent networks by means of coevolution

    International Nuclear Information System (INIS)

    Wang, Zhen; Szolnoki, Attila; Perc, Matjaž

    2014-01-01

    Coevolution between strategy and network structure is established as a means to arrive at the optimal conditions needed to resolve social dilemmas. Yet recent research has highlighted that the interdependence between networks may be just as important as the structure of an individual network. We therefore introduce the coevolution of strategy and network interdependence to see whether this can give rise to elevated levels of cooperation in the prisoner's dilemma game. We show that the interdependence between networks self-organizes so as to yield optimal conditions for the evolution of cooperation. Even under extremely adverse conditions, cooperators can prevail where on isolated networks they would perish. This is due to the spontaneous emergence of a two-class society, with only the upper class being allowed to control and take advantage of the interdependence. Spatial patterns reveal that cooperators, once arriving at the upper class, are much more competent than defectors in sustaining compact clusters of followers. Indeed, the asymmetric exploitation of interdependence confers to them a strong evolutionary advantage that may resolve even the toughest of social dilemmas. (paper)

  20. Early Prevention of Instability-Use of Self Propagating Graph for the Fast Search for Optimal Grid Nodes to Apply Countermeasures

    DEFF Research Database (Denmark)

    Dmitrova, Evgenia; Jóhannsson, Hjörtur; Nielsen, Arne Hejde

    2013-01-01

    This paper presents a method for a fast determination of the grid nodes where countermeasures, in the form of changes in nodal admittance, would provide greatest impact on the stability margin for a specific generator that is facing the risk of instability. The sensitivity of the stability criter...... of the developed approach for the fast identification of the optimal nodes for countermeasure application....

  1. The mediating role of self-stigma and unmet needs on the recovery of people with schizophrenia living in the community.

    Science.gov (United States)

    Chan, Kevin K S; Mak, Winnie W S

    2014-11-01

    For people with schizophrenia living in the community and receiving outpatient care, the issues of stigma and discrimination and dearth of recovery-oriented services remain barriers to recovery and community integration. The experience of self-stigma and unmet recovery needs can occur regardless of symptom status or disease process, reducing life satisfaction and disrupting overall well-being. The present study examined the mediating role of self-stigma and unmet needs in the relationship between psychiatric symptom severity and subjective quality of life. Structural equation modeling and mediation analyses were conducted based on a community sample of 400 mental health consumers with schizophrenia spectrum disorders in Hong Kong. The model of self-stigma and unmet needs as mediators between symptom severity and subjective quality of life had good fit to the data (GFI = .93, CFI = .93, NNFI = .92, RMSEA = .06, χ(2)/df ratio = 2.62). A higher level of symptom severity was significantly associated with increased self-stigma (R (2) = .24) and a greater number of unmet needs (R (2) = .53). Self-stigma and unmet needs were in turn negatively related to subjective quality of life (R (2) = .45). It is essential that service providers and administrators make greater efforts to eliminate or reduce self-stigma and unmet recovery needs, which are associated with the betterment of the overall quality of life and long-term recovery. Both incorporating empowerment and advocacy-based interventions into recovery-oriented services and providing community-based, person-centered services to people based on personally defined needs are important directions for future recovery-oriented efforts.

  2. Identifying Two Groups of Entitled Individuals: Cluster Analysis Reveals Emotional Stability and Self-Esteem Distinction.

    Science.gov (United States)

    Crowe, Michael L; LoPilato, Alexander C; Campbell, W Keith; Miller, Joshua D

    2016-12-01

    The present study hypothesized that there exist two distinct groups of entitled individuals: grandiose-entitled, and vulnerable-entitled. Self-report scores of entitlement were collected for 916 individuals using an online platform. Model-based cluster analyses were conducted on the individuals with scores one standard deviation above mean (n = 159) using the five-factor model dimensions as clustering variables. The results support the existence of two groups of entitled individuals categorized as emotionally stable and emotionally vulnerable. The emotionally stable cluster reported emotional stability, high self-esteem, more positive affect, and antisocial behavior. The emotionally vulnerable cluster reported low self-esteem and high levels of neuroticism, disinhibition, conventionality, psychopathy, negative affect, childhood abuse, intrusive parenting, and attachment difficulties. Compared to the control group, both clusters reported being more antagonistic, extraverted, Machiavellian, and narcissistic. These results suggest important differences are missed when simply examining the linear relationships between entitlement and various aspects of its nomological network.

  3. Optimization of Photovoltaic Self-consumption using Domestic Hot Water Systems

    Directory of Open Access Journals (Sweden)

    Ângelo Casaleiro

    2018-06-01

    Full Text Available Electrified domestic hot water systems, being deferrable loads, are an important demand side management tool and thus have the potential to enhance photovoltaic self-consumption. This study addresses the energy and economic performance of photovoltaic self-consumption by using a typical Portuguese dwelling. Five system configurations were simulated: a gas boiler (with/without battery and an electric boiler (without demand management and with genetic and heuristic optimization. A sensitivity analysis on photovoltaic capacity shows the optimum photovoltaic sizing to be in the range 1.0 to 2.5 kWp. The gas boiler scenario and the heuristic scenario present the best levelized cost of energy, respectively, for the lower and higher photovoltaic capacities. The use of a battery shows the highest levelized cost of energy and the heuristic scenario shows the highest solar fraction (56.9%. Results also highlight the great potential on increasing photovoltaic size when coupled with electrified domestic hot water systems, to accommodate higher solar fractions and achieve lower costs, through energy management.

  4. One-step polypyrrole coating of self-assembled silver nanoprisms for enhanced stability and Raman scattering

    Science.gov (United States)

    Jeong, Dong-Won; Jeong, Sugyeong; Jang, Du-Jeon

    2017-07-01

    Self-assemblies of silver nanoprisms (AgPRs) having enhanced structural stability and optical properties have been facilely coated with polypyrrole (PPy) via the in situ polymerization of pyrrole monomers that also act as an assembling agent. The assemblies of AgPRs, whose edge lengths and thicknesses are typically 78 and 4 nm, respectively, have been surrounded by a PPy coating of 6 nm. AgPRs are assembled in a side-to-side orientation, and the degree of assembly has been controlled by varying the concentration of trisodium citrate dihydrate, which attaches selectively to the {111} facets of AgPRs. The morphology deformation time of PPy-coated AgPRs in 0.6 mM H2O2(aq) is seven times longer than that of PPy-free AgPRs, suggesting that PPy coating prevents the sharp tips of AgPRs from being truncated by oxidizing agents. The SERS effect of highly self-assembled and PPy-coated AgPRs becomes as high as 6.3 due to numerous hot spots generated between nanoprisms. Overall, our fabricated AgPRs assemblies with PPy coating have not only improved structural stability but also enhanced optical properties, extending the practical use of noble-metal nanoprisms for various optical applications.

  5. Protein stability: a crystallographer’s perspective

    International Nuclear Information System (INIS)

    Deller, Marc C.; Kong, Leopold; Rupp, Bernhard

    2016-01-01

    An understanding of protein stability is essential for optimizing the expression, purification and crystallization of proteins. In this review, discussion will focus on factors affecting protein stability on a somewhat practical level, particularly from the view of a protein crystallographer. Protein stability is a topic of major interest for the biotechnology, pharmaceutical and food industries, in addition to being a daily consideration for academic researchers studying proteins. An understanding of protein stability is essential for optimizing the expression, purification, formulation, storage and structural studies of proteins. In this review, discussion will focus on factors affecting protein stability, on a somewhat practical level, particularly from the view of a protein crystallographer. The differences between protein conformational stability and protein compositional stability will be discussed, along with a brief introduction to key methods useful for analyzing protein stability. Finally, tactics for addressing protein-stability issues during protein expression, purification and crystallization will be discussed

  6. Protein stability: a crystallographer’s perspective

    Energy Technology Data Exchange (ETDEWEB)

    Deller, Marc C., E-mail: mdeller@stanford.edu [Stanford University, Shriram Center, 443 Via Ortega, Room 097, MC5082, Stanford, CA 94305-4125 (United States); Kong, Leopold [National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK), National Institutes of Health (NIH), Building 8, Room 1A03, 8 Center Drive, Bethesda, MD 20814 (United States); Rupp, Bernhard [k.-k. Hofkristallamt, 91 Audrey Place, Vista, CA 92084 (United States); Medical University of Innsbruck, Schöpfstrasse 41, A-6020 Innsbruck (Austria)

    2016-01-26

    An understanding of protein stability is essential for optimizing the expression, purification and crystallization of proteins. In this review, discussion will focus on factors affecting protein stability on a somewhat practical level, particularly from the view of a protein crystallographer. Protein stability is a topic of major interest for the biotechnology, pharmaceutical and food industries, in addition to being a daily consideration for academic researchers studying proteins. An understanding of protein stability is essential for optimizing the expression, purification, formulation, storage and structural studies of proteins. In this review, discussion will focus on factors affecting protein stability, on a somewhat practical level, particularly from the view of a protein crystallographer. The differences between protein conformational stability and protein compositional stability will be discussed, along with a brief introduction to key methods useful for analyzing protein stability. Finally, tactics for addressing protein-stability issues during protein expression, purification and crystallization will be discussed.

  7. Self-Empowerment of Immigrant Latina Survivors of Domestic Violence: A Promotora Model of Community Leadership.

    Science.gov (United States)

    Serrata, Josephine V; Hernandez-Martinez, Martha; Macias, R Lillianne

    2016-03-01

    This article presents the results of a self-empowerment leadership intervention program for Latina immigrant survivors of domestic violence in Atlanta, Georgia. It builds on the literature base of the Promotora model, a public health model using peer information sharing as a tool for health promotion. This study used an embedded mixed-methods design with quantitative and qualitative components to evaluate the impact of a peer community leadership program called Líderes Results of single-subject analyses show that the participants experienced change in three components of self-empowerment: intrapersonal, interactional, and behavioral. The qualitative findings revealed that they overcame fear and gained knowledge as well as a sense that they could promote change in their community. These findings add support to a growing literature base that demonstrates how peer model programs can not only positively influence the well-being of the communities they serve but also have transformative effects on peer leaders themselves. Study findings can also inform future efforts to empower survivors through promotora approaches specifically in the context of domestic violence prevention. © 2016. All rights reserved.

  8. Theorizing the lesbian hashtag: Identity, community, and the technological imperative to name the sexual self.

    Science.gov (United States)

    Herrera, Andrea P

    2017-11-27

    This analysis integrates poststructuralist and symbolic interactionist approaches to the self by incorporating the insights of science and technology studies regarding categorization processes. While the advent of the Internet has freed many individuals from geographical constraints on community formation, the architectures of online platforms produce a technological imperative to name aspects of the self with words. Using sexual identity hashtags on Instagram (e.g., #lesbian) thus performs paradoxical functions: the hashtag both enables the construction of a sexual identity within an affirming community and also reinforces the power relations that compel individuals to name and account for their sexual selves. By illustrating one way sexual identities function in the online lives of young women, this research complicates other scholars' findings that the salience of sexual identity categories is decreasing.

  9. An Investigation of Participation in Weekly Music Workshops and Its Relationship to Academic Self-Concept and Self-Esteem of Middle School Students in Low-Income Communities

    Science.gov (United States)

    Shin, Jihae

    2011-01-01

    The purpose of this study was to examine how I Am A Dreamer Musician Program (IDMP) affected academic self-concept and self-esteem of middle school students in low-income communities. During the seven weeks of the weekly music workshops, students participated in different musical activities including playing percussion instruments, singing,…

  10. The Association of Age, Sense of Control, Optimism, and Self-Esteem with Emotional Distress

    Science.gov (United States)

    Jiménez, M. Guadalupe; Montorio, Ignacio; Izal, María

    2017-01-01

    The aim of this study was to test a model of emotional distress, which incorporates the potential mediator role of positive resources (sense of control, self-esteem, and optimism) in the association of age with emotional distress. The study used a cross-sectional design with intentional sampling and the voluntary participation of 325 adults…

  11. Optimization of an Autonomous Car Controller Using a Self-Adaptive Evolutionary Strategy

    Directory of Open Access Journals (Sweden)

    Tae Seong Kim

    2012-09-01

    Full Text Available Autonomous cars control the steering wheel, acceleration and the brake pedal, the gears and the clutch using sensory information from multiple sources. Like a human driver, it understands the current situation on the roads from the live streaming of sensory values. The decision-making module often suffers from the limited range of sensors and complexity due to the large number of sensors and actuators. Because it is tedious and difficult to design the controller manually from trial-and-error, it is desirable to use intelligent optimization algorithms. In this work, we propose optimizing the parameters of an autonomous car controller using self-adaptive evolutionary strategies (SAESs which co-evolve solutions and mutation steps for each parameter. We also describe how the most generalized parameter set can be retrieved from the process of optimization. Open-source car racing simulation software (TORCS is used to test the goodness of the proposed methods on 6 different tracks. Experimental results show that the SAES is competitive with the manual design of authors and a simple ES.

  12. The Impact of Community Service Involvement on Three Measures of Undergraduate Self-Concept.

    Science.gov (United States)

    Berger, Joseph B.; Milem, Jeff F.

    2002-01-01

    The central purpose of this study is to increase our understanding of how community service involvement affects the development of undergraduate self-concept. The findings from this study suggest that the quality of service involvement is more important than the amount of service performed by students. (Contains 23 references and 2 tables.)…

  13. Community

    Science.gov (United States)

    stability Science & Innovation Collaboration Careers Community Environment Science & Innovation Recruitment Events Community Commitment Giving Campaigns, Drives Economic Development Employee Funded neighbor pledge: contribute to quality of life in Northern New Mexico through economic development

  14. Changes in vegetation and biological soil crust communities on sand dunes stabilizing after a century of grazing on San Miguel Island, Channel Island National Park, California

    Science.gov (United States)

    Zellman, Kristine L.

    2014-01-01

    San Miguel Island is the westernmost of the California Channel Islands and one of the windiest areas on the west coast of North America. The majority of the island is covered by coastal sand dunes, which were stripped of vegetation and subsequently mobilized due to droughts and sheep ranching during the late 19th century and early 20th century. Since the removal of grazing animals, vegetation and biological soil crusts have once again stabilized many of the island's dunes. In this study, historical aerial photographs and field surveys were used to develop a chronosequence of the pattern of change in vegetation communities and biological soil crust levels of development (LOD) along a gradient of dune stabilization. Historical aerial photographs from 1929, 1954, 1977, and 2009 were georeferenced and used to delineate changes in vegetation canopy cover and active (unvegetated) dune extent among 5 historical periods (pre-1929, 1929–1954, 1954–1977, 1977–2009, and 2009–2011). During fieldwork, vegetation and biological soil crust communities were mapped along transects distributed throughout San Miguel Island's central dune field on land forms that had stabilized during the 5 time periods of interest. Analyses in a geographic information system (GIS) quantified the pattern of changes that vegetation and biological soil crust communities have exhibited on the San Miguel Island dunes over the past 80 years. Results revealed that a continuing increase in total vegetation cover and a complex pattern of change in vegetation communities have taken place on the San Miguel Island dunes since the removal of grazing animals. The highly specialized native vascular vegetation (sea rocket, dunedelion, beach-bur, and locoweed) are the pioneer stabilizers of the dunes. This pioneer community is replaced in later stages by communities that are dominated by native shrubs (coastal goldenbush, silver lupine, coyote-brush, and giant coreopsis), with apparently overlapping or

  15. An Improved Method for Reconfiguring and Optimizing Electrical Active Distribution Network Using Evolutionary Particle Swarm Optimization

    Directory of Open Access Journals (Sweden)

    Nur Faziera Napis

    2018-05-01

    Full Text Available The presence of optimized distributed generation (DG with suitable distribution network reconfiguration (DNR in the electrical distribution network has an advantage for voltage support, power losses reduction, deferment of new transmission line and distribution structure and system stability improvement. However, installation of a DG unit at non-optimal size with non-optimal DNR may lead to higher power losses, power quality problem, voltage instability and incremental of operational cost. Thus, an appropriate DG and DNR planning are essential and are considered as an objective of this research. An effective heuristic optimization technique named as improved evolutionary particle swarm optimization (IEPSO is proposed in this research. The objective function is formulated to minimize the total power losses (TPL and to improve the voltage stability index (VSI. The voltage stability index is determined for three load demand levels namely light load, nominal load, and heavy load with proper optimal DNR and DG sizing. The performance of the proposed technique is compared with other optimization techniques, namely particle swarm optimization (PSO and iteration particle swarm optimization (IPSO. Four case studies on IEEE 33-bus and IEEE 69-bus distribution systems have been conducted to validate the effectiveness of the proposed IEPSO. The optimization results show that, the best achievement is done by IEPSO technique with power losses reduction up to 79.26%, and 58.41% improvement in the voltage stability index. Moreover, IEPSO has the fastest computational time for all load conditions as compared to other algorithms.

  16. Cardiac Coherence, Self-Regulation, Autonomic Stability and Psychosocial Well-being

    Directory of Open Access Journals (Sweden)

    Rollin eMcCraty

    2014-09-01

    Full Text Available The ability to alter one’s emotional responses is central to overall well-being and to effectively meeting the demands of life. One of the chief symptoms of events such as trauma, that overwhelm our capacities to successfully handle and adapt to them, is a shift in our internal baseline reference such that there ensues a repetitive activation of the traumatic event. This can result in high vigilance and over-sensitivity to environmental signals which are reflected in inappropriate emotional responses and autonomic nervous system dynamics. In this article we discuss the perspective that one’s ability to self-regulate the quality of feeling and emotion of one’s moment-to-moment experience is intimately tied to our physiology, and the reciprocal interactions among physiological, cognitive and emotional systems. These interactions form the basis of information processing networks in which communication between systems occurs through the generation and transmission of rhythms and patterns of activity. Our discussion emphasizes the communication pathways between the heart and brain, as well as how these are related to cognitive and emotional function and self-regulatory capacity. We discuss the hypothesis that self-induced positive emotions increase the coherence in bodily processes, which is reflected in the pattern of the heart’s rhythm. This shift in the heart rhythm in turn plays an important role in facilitating higher cognitive functions, creating emotional stability and facilitating states of calm. Over time, this establishes a new inner-baseline reference, a type of implicit memory that organizes perception, feelings and behavior. Without establishing a new baseline reference, people are at risk of getting stuck in familiar, yet unhealthy emotional and behavioral patterns and living their lives through the automatic filters of past familiar or traumatic experience.

  17. Association of depression and pain interference with disease-management self-efficacy in community-dwelling individuals with spinal cord injury.

    Science.gov (United States)

    Pang, Marco Y C; Eng, Janice J; Lin, Kwan-Hwa; Tang, Pei-Fang; Hung, Chihya; Wang, Yen-Ho

    2009-11-01

    To determine factors influencing disease-management self-efficacy in individuals with spinal cord injury. A cross-sectional study. Forty-nine community-dwelling individuals with chronic spinal cord injury (mean age 44 years) participated in the study. Each subject was evaluated for disease-management self-efficacy (Self-efficacy for Managing Chronic Disease), depression (10-item Center for Epidemiologic Studies Depression Scale), pain interference (Pain Interference Scale), and availability of support (Interpersonal Support Evaluation List short form). Multiple regression analysis was performed to determine the relative contributions of these factors to disease-management self-efficacy. The mean disease-management self-efficacy score was 6.5 out of 10 (standard deviation 1.6). Bivariate correlation analysis showed that higher self-efficacy was significantly correlated with longer time since injury (r = 0.367, p = 0.010), better social support (r = 0.434, p = 0.002), lower pain interference (r = -0.589, p management self-efficacy (F 4,44=10.249, R2=0.482, pmanagement self-efficacy is suboptimal in many community-living people with spinal cord injury. This research suggests that rehabilitation of patients with spinal cord injury should include self-efficacy-enhancing strategies. Alleviation of depressive symptoms and pain self-management may be important for improving disease-management self-efficacy in this population, but this requires further study.

  18. [A study of factors influenced by self-efficacy for exercise among community-dwelling elderly men in urban areas].

    Science.gov (United States)

    Takai, Itsushi

    2012-01-01

    It is important to promote self-efficacy for exercise for developing exercise habit. The purpose of this study was to investigate factors influenced by self-efficacy for exercise among community-dwelling elderly men in urban areas. The subjects were 69 elderly men (mean age of 74.2±2.0 SD) who had given approval for participation in the study. We examined the following factors: family situation, history of falls, frequency of going out, stage model of a change, self-efficacy for exercise, fall efficacy scale (FES), geriatric depression scale (GDS), subjective health, functional ability and motor function (5 m walking time, chair stand test-5times). Analysis of variance was used to assess a stage model of a change differences in self-efficacy for exercise and other measures. Correlation analysis and multiple regression analysis were performed to determine the relationships between self-efficacy for exercise and other measures. We found that self-efficacy of exercise, FES, GDS (pSelf-efficacy for exercise was found to correlate with psychological factors and functional ability (|r|=0.47-0.67). Multiple regression analysis revealed that the independent factors related to self-efficacy for exercise were FES and GDS. FES and GDS were found to be significant and independent predictors of self-efficacy for exercise in community-dwelling elderly men in urban areas. We should consider not only the approach based on behavioral science but also mental support for depression and fear of falling to promote exercise self-efficacy.

  19. Condom use peer norms and self-efficacy as mediators between community engagement and condom use among Chinese men who have sex with men

    Directory of Open Access Journals (Sweden)

    Haochu Li

    2017-08-01

    Full Text Available Abstract Background Community engagement strategies are often integrated in public health interventions designed to promote condom use among men who have sex with men (MSM, a key population for HIV prevention. However, the ways in which condom use peer norms and self-efficacy play a role in the association between community engagement and condom use is unclear. This study examines the potential mediating roles of peer norms and self-efficacy in this association. Methods A nationwide cross-sectional online survey was conducted among Chinese MSM in 2015. Recruitment criteria included being born biologically male, being older than 16 years, having had anal sex with a man at least once during their lifetime, and having had condomless anal or vaginal sex in the past three months. Mplus 6.11 was used to conduct confirmatory factor analysis and path modeling analysis to examine the structural relationships between HIV/sexual health community engagement (e.g., joining social media and community events related to HIV and sexual health services, condom use peer norms, condom use self-efficacy, and frequency of condom use. Results The study found that HIV/sexual health community engagement, condom use peer norms, condom use self-efficacy, and frequency of condom use were mutually correlated. A good data model was achieved with fit index: CFI = 0.988, TLI = 0.987, RMSEA = 0.032, 90% CI (0.028, 0.036. HIV/sexual health community engagement was associated with frequency of condom use, which was directly mediated by condom use peer norms and indirectly through self-efficacy. Conclusion The study suggests that condom use peer norms and self-efficacy may be mediators in the pathway between community engagement and condom use, and suggests the importance of peer-based interventions to improve condom use.

  20. Condom use peer norms and self-efficacy as mediators between community engagement and condom use among Chinese men who have sex with men.

    Science.gov (United States)

    Li, Haochu; Xue, Li; Tucker, Joseph D; Wei, Chongyi; Durvasula, Maya; Hu, Wenqi; Kang, Dianming; Liao, Meizhen; Tang, Weiming; Ma, Wei

    2017-08-07

    Community engagement strategies are often integrated in public health interventions designed to promote condom use among men who have sex with men (MSM), a key population for HIV prevention. However, the ways in which condom use peer norms and self-efficacy play a role in the association between community engagement and condom use is unclear. This study examines the potential mediating roles of peer norms and self-efficacy in this association. A nationwide cross-sectional online survey was conducted among Chinese MSM in 2015. Recruitment criteria included being born biologically male, being older than 16 years, having had anal sex with a man at least once during their lifetime, and having had condomless anal or vaginal sex in the past three months. Mplus 6.11 was used to conduct confirmatory factor analysis and path modeling analysis to examine the structural relationships between HIV/sexual health community engagement (e.g., joining social media and community events related to HIV and sexual health services), condom use peer norms, condom use self-efficacy, and frequency of condom use. The study found that HIV/sexual health community engagement, condom use peer norms, condom use self-efficacy, and frequency of condom use were mutually correlated. A good data model was achieved with fit index: CFI = 0.988, TLI = 0.987, RMSEA = 0.032, 90% CI (0.028, 0.036). HIV/sexual health community engagement was associated with frequency of condom use, which was directly mediated by condom use peer norms and indirectly through self-efficacy. The study suggests that condom use peer norms and self-efficacy may be mediators in the pathway between community engagement and condom use, and suggests the importance of peer-based interventions to improve condom use.

  1. Econometric analysis to evaluate the effect of community-based health insurance on reducing informal self-care in Burkina Faso.

    Science.gov (United States)

    Robyn, Paul Jacob; Hill, Allan; Liu, Yuanli; Souares, Aurélia; Savadogo, Germain; Sié, Ali; Sauerborn, Rainer

    2012-03-01

    This study examines the role of community-based health insurance (CBHI) in influencing health-seeking behaviour in Burkina Faso, West Africa. Community-based health insurance was introduced in Nouna district, Burkina Faso, in 2004 with the goal to improve access to contracted providers based at primary- and secondary-level facilities. The paper specifically examines the effect of CBHI enrolment on reducing the prevalence of seeking modern and traditional methods of self-treatment as the first choice in care among the insured population. Three stages of analysis were adopted to measure this effect. First, propensity score matching was used to minimize the observed baseline differences between the insured and uninsured populations. Second, through matching the average treatment effect on the treated, the effect of insurance enrolment on health-seeking behaviour was estimated. Finally, multinomial logistic regression was applied to model demand for available health care options, including no treatment, traditional self-treatment, modern self-treatment, traditional healers and facility-based care. For the first choice in care sought, there was no significant difference in the prevalence of self-treatment among the insured and uninsured populations, reaching over 55% for each group. When comparing the alternative option of no treatment, CBHI played no significant role in reducing the demand for self-care (either traditional or modern) or utilization of traditional healers, while it did significantly increase consumption of facility-based care. The average treatment effect on the treated was insignificant for traditional self-care, modern self-care and traditional healer, but was significant with a positive effect for use of facility care. While CBHI does have a positive impact on facility care utilization, its effect on reducing the prevalence of self-care is limited. The policy recommendations for improving the CBHI scheme's responsiveness to population health care

  2. Stability assessment and operating parameter optimization on experimental results in very small plasma focus, using sensitivity analysis

    Science.gov (United States)

    Jafari, Hossein; Habibi, Morteza

    2018-04-01

    Regarding the importance of stability in small-scale plasma focus devices for producing the repeatable and strength pinching, a sensitivity analysis approach has been used for applicability in design parameters optimization of an actually very low energy device (84 nF, 48 nH, 8-9.5 kV, ∼2.7-3.7 J). To optimize the devices functional specification, four different coaxial electrode configurations have been studied, scanning an argon gas pressure range from 0.6 to 1.5 mbar via the charging voltage variation study from 8.3 to 9.3 kV. The strength and efficient pinching was observed for the tapered anode configuration, over an expanded operating pressure range of 0.6 to 1.5 mbar. The analysis results showed that the most sensitive of the pinch voltage was associated with 0.88 ± 0.8mbar argon gas pressure and 8.3-8.5 kV charging voltage, respectively, as the optimum operating parameters. From the viewpoint of stability assessment of the device, it was observed that the least variation in stable operation of the device was for a charging voltage range of 8.3 to 8.7 kV in an operating pressure range from 0.6 to 1.1 mbar.

  3. Supporting self management of type 2 diabetes: is there a role for the community pharmacist?

    Directory of Open Access Journals (Sweden)

    Dhippayom T

    2015-07-01

    Full Text Available Teerapon Dhippayom,1 Ines Krass21Pharmaceutical Care Research Unit, Department of Pharmacy Practice, Faculty of Pharmaceutical Sciences, Naresuan University, Phitsanulok, Thailand; 2Faculty of Pharmacy, The University of Sydney, Camperdown, NSW, AustraliaBackground: Evidence supports the efficacy of pharmacy services in type 2 diabetes (T2D. However, little is known about consumer perspectives on the role of community pharmacists in diabetes care. The objectives of this study were to identify potential unmet needs and explore preferences for pharmacist-delivered support for T2D.Methods: A qualitative study using focus groups was conducted in Sydney, Australia. Patients with T2D who were members of the Australian Diabetes Council in Sydney, Australia, were recruited through a survey on medication use in T2D. Five focus groups with a total of 32 consumers with T2D were recorded, transcribed, and thematically analyzed.Results: The key themes were 1 the experiences of diabetes services received, 2 the potential to deliver self-management services, and 3 the suggested role of pharmacist in supporting diabetes management. Gaps in understanding and some degree of nonadherence to self-management signaled a potential for self-management support delivered by pharmacists. However, consumers still perceive that the main role of pharmacists in diabetes care centers on drug management services, with some enhancements to support adherence and continuity of supply. Barriers to diabetes care services included time constraints and a perceived lack of interest by pharmacists.Conclusion: Given the unmet needs in diabetes self-management, opportunities exist for pharmacists to be involved in diabetes care. The challenge is for pharmacists to upgrade their diabetes knowledge and skills, organize their workflow, and become proactive in delivering diabetes care support.Keywords: diabetes care, community pharmacy, community pharmacist, self-management, preference

  4. Improving the quality of learning in science through optimization of lesson study for learning community

    Science.gov (United States)

    Setyaningsih, S.

    2018-03-01

    Lesson Study for Learning Community is one of lecturer profession building system through collaborative and continuous learning study based on the principles of openness, collegiality, and mutual learning to build learning community in order to form professional learning community. To achieve the above, we need a strategy and learning method with specific subscription technique. This paper provides a description of how the quality of learning in the field of science can be improved by implementing strategies and methods accordingly, namely by applying lesson study for learning community optimally. Initially this research was focused on the study of instructional techniques. Learning method used is learning model Contextual teaching and Learning (CTL) and model of Problem Based Learning (PBL). The results showed that there was a significant increase in competence, attitudes, and psychomotor in the four study programs that were modelled. Therefore, it can be concluded that the implementation of learning strategies in Lesson study for Learning Community is needed to be used to improve the competence, attitude and psychomotor of science students.

  5. Nanocarrier with self-antioxidative property for stabilizing and delivering ascorbyl palmitate into skin.

    Science.gov (United States)

    Janesirisakule, Sirinapa; Sinthusake, Tarit; Wanichwecharungruang, Supason

    2013-08-01

    The concept of a nanocarrier with a self-antioxidative property to deliver and stabilize a labile drug while at the same time providing a free radical scavenging activity is demonstrated. Curcumin was grafted onto a poly(vinyl alcohol) [PV(OH)] chain, and the nanocarriers fabricated from the obtained curcumin-grafted PV(OH) polymer [CUR-PV(OH)] showed a good free radical scavenging activity. Ascorbyl palmitate (AP) could be effectively loaded into the CUR-PV(OH) at 29% by weight. The CUR-PV(OH)-encapsulated AP was 77% more stable than the free (unencapsulated) AP, and 47% more stable than AP encapsulated in the control nanocarrier with no antioxidative property [cinnamoyl-grafted PV(OH); CIN-PV(OH)]. Although coencapsulation of curcumin and AP into CIN-PV(OH) showed some improvement on the AP stability, AP was more stable when encapsulated in CUR-PV(OH). Compared with the free AP, encapsulated AP within the CUR-PV(OH) nanocarriers showed not only a better penetration into pig skin dermis via hair follicle pathway followed by the release and diffusion of the AP, but also a greater AP stability after skin application. Although a proof of principle is shown for CUR-PV(OH) and AP, it is likely that other carriers of the same principal could be designed and applied to different oxidation-sensitive drugs. Copyright © 2013 Wiley Periodicals, Inc.

  6. Self-Stigma and Quality of Life among People with Mental Illness Who Receive Compulsory Community Treatment Services

    Science.gov (United States)

    Livingston, James

    2012-01-01

    The present study was designed to examine the relationship between self-stigma and quality of life over a one year time period for 71 people with mental illness who were receiving compulsory community mental health treatment. It was hypothesized that, over time, self-stigma would have the direct effect of eroding quality of life among people with…

  7. A new self-firing MOS-thyristor device: optimization of the turn-off performance and experimental results

    Energy Technology Data Exchange (ETDEWEB)

    Breil, M.; Sanchez, J.L.; Austin, P.; Laur, J.P.

    1998-12-01

    In this paper, a new integrated self-firing and controlled turn-off MOS-thyristor structure is investigated. An analytical model describing the turn-off operation and parasitic latch-up has been developed, allowing to highlight and optimize the physical and geometrical parameters acting upon main electrical characteristics. The analytical model is validated by 2D simulations using PISCES. The technological fabrication process is optimized by 2D simulations using SUPREM IV. Electrical characterization results of fabricated test structures are presented. (authors) 6 refs.

  8. Stabilized soliton self-frequency shift and 0.1- PHz sideband generation in a photonic-crystal fiber with an air-hole-modified core.

    Science.gov (United States)

    Liu, Bo-Wen; Hu, Ming-Lie; Fang, Xiao-Hui; Li, Yan-Feng; Chai, Lu; Wang, Ching-Yue; Tong, Weijun; Luo, Jie; Voronin, Aleksandr A; Zheltikov, Aleksei M

    2008-09-15

    Fiber dispersion and nonlinearity management strategy based on a modification of a photonic-crystal fiber (PCF) core with an air hole is shown to facilitate optimization of PCF components for a stable soliton frequency shift and subpetahertz sideband generation through four-wave mixing. Spectral recoil of an optical soliton by a red-shifted dispersive wave, generated through a soliton instability induced by high-order fiber dispersion, is shown to stabilize the soliton self-frequency shift in a highly nonlinear PCF with an air-hole-modified core relative to pump power variations. A fiber with a 2.3-microm-diameter core modified with a 0.9-microm-diameter air hole is used to demonstrate a robust soliton self-frequency shift of unamplified 50-fs Ti: sapphire laser pulses to a central wavelength of about 960 nm, which remains insensitive to variations in the pump pulse energy within the range from 60 to at least 100 pJ. In this regime of frequency shifting, intense high- and low-frequency branches of dispersive wave radiation are simultaneously observed in the spectrum of PCF output. An air-hole-modified-core PCF with appropriate dispersion and nonlinearity parameters is shown to provide efficient four-wave mixing, giving rise to Stokes and anti-Stokes sidebands whose frequency shift relative to the pump wavelength falls within the subpetahertz range, thus offering an attractive source for nonlinear Raman microspectroscopy.

  9. Control mechanisms for battery energy storage system performing primary frequency regulation and self-consumption optimization

    NARCIS (Netherlands)

    Pliatskas Stylianidis, A.

    2016-01-01

    This report contains the design of a model for the integration of a battery energy system in a household level and its use for primary frequency regulation and self-consumption optimization. The main goal of this project was to investigate what are the possible applications and the most suitable for

  10. Community-based asthma care: trial of a "credit card" asthma self-management plan.

    Science.gov (United States)

    D'Souza, W; Crane, J; Burgess, C; Te Karu, H; Fox, C; Harper, M; Robson, B; Howden-Chapman, P; Crossland, L; Woodman, K

    1994-07-01

    Although asthma self-management plans are widely recommended as essential in the long-term treatment of adult asthma, there have been few studies examining their use. Our objective was to assess the effect of a "credit card" adult asthma self-management plan in a community experiencing major health problems from asthma, by means of a before and after intervention trial of the efficacy of the "credit card" plan, when introduced through community-based asthma clinics. The participants were 69 Maori people with asthma. The "credit card" plan consisted of written guidelines for the self-management of asthma, based on self-assessment of asthma severity, printed on a plastic card. On one side, management guidelines were based on the interpretation of peak expiratory flow rate (PEFR) recordings, whilst the reverse side was based on symptoms. The outcome measures used were before and after comparison of markers of asthma morbidity and requirement for acute medical treatment; and a structured questionnaire assessing the acceptability and use of the credit card plan. Following the introduction of the plan, the mean PEFR increased from 347 to 389 l.min-1, the percentage of nights woken fell from 30.4 to 16.9%, and the number of days "out of action" fell from 3.8 to 1.7%. The requirements for acute medical treatment also fell during the intervention period. Most participants commented favourably on the content and usefulness of the plan. In the situation of worsening asthma, 28% of subjects found the peak flow side of the card most helpful, 7% the symptoms side, and 48% found both sides equally helpful.(ABSTRACT TRUNCATED AT 250 WORDS)

  11. Does community capacity influence self-rated health? Multilevel contextual effects in Seoul, Korea.

    Science.gov (United States)

    Jung, Minsoo; Viswanath, K

    2013-01-01

    This study examined the relationship between community-level contextual effects and self-rated health (SRH) based on the perspective of community capacity rather than social capital. Community capacity for mobilization is broad cooperation for networking among indigenous social agents and grassroots organizations that may serve as potential resources. The idea of community capacity is rooted in the philosophy that a community not only faces problems but also possesses the necessary resources to solve its problems. We used nationally representative data from South Korea, 2010, drawing on 14,228 residents in 404 communities. Community capacity was measured at two levels: an individual-level indicator of community satisfaction, and community-level indicators of participation rate in community organizations, number of community-based organizations (CBOs), and number of volunteer work camps (VWCs). The outcome variable was SRH, which was categorized into two groups: the low-SRH and high-SRH groups. Confounders included gender, age, and income at the individual level, and aggregate length of residency, financial independence ratio, and aggregate income at the community level. We estimated the effects of community capacity on SRH using hierarchical generalized linear models. The likelihood of belonging to the group having low-SRH is significantly high among those respondents living in places with lower community capacity at the community level, that report lower community satisfaction, and that have lower income at the individual level. After controlling for socio-economic confounders, the odds ratios were attenuated but remained significant in the final model, which included the gender-specific model. This study revealed that SRH is related to the level of community capacity for mobilization. It is probably because CBOs and VWCs not only provide necessary information and complementary services but also play an active role in identifying and resolving health problems

  12. Self-perceived health status and sleep quality of older adults living in community after elastic band exercises.

    Science.gov (United States)

    Chan, Shu-Ya; Chen, Kuei-Min

    2017-07-01

    To test the effectiveness of a six-month senior elastic band exercise programme on the self-perceived health status and sleep quality of older adults living in community settings. Health issues common among older adults living in community settings include poor physical and mental health conditions and sleep quality. Engagement in appropriate exercise programmes facilitates alleviating these health issues among older adults. A quasi-experimental design was applied. A convenience sample of older adults was drawn from six senior-citizen activity centres in southern Taiwan. Participants were assigned to either an experimental group (three centres, n = 97) or a control group (three centres, n = 102) based on the senior-citizen activity centres they attended. The participants in the experimental group carried out the Senior Elastic Band exercise programme for six months (three times per week and 40 minutes per session) in addition to their daily activities. The participants in the control group maintained their daily activities. The participants' self-perceived health status and sleep quality were examined at the baseline, three-month interval and six-month interval. In total, 169 participants completed the six-month study: 84 constituted the experimental group and 85 constituted the control group. At the three-month interval, the participants in the experimental group had greater improvements in self-perceived physical health, overall sleep quality, sleep latency and sleep duration compared with those in the control group; these significant changes continued throughout the six-month study. The Senior Elastic Band exercise programme showed promising effects in improving the self-perceived physical health and sleep quality of older adults living in community settings. Healthcare professionals can incorporate the Senior Elastic Band exercise programme as one of the health promotion activities for older adults living in community settings. © 2016 John Wiley & Sons

  13. Validity and reliability of self-reported diabetes in the Atherosclerosis Risk in Communities Study.

    Science.gov (United States)

    Schneider, Andrea L C; Pankow, James S; Heiss, Gerardo; Selvin, Elizabeth

    2012-10-15

    The objective of this study was to assess the validity of prevalent and incident self-reported diabetes compared with multiple reference definitions and to assess the reliability (repeatability) of a self-reported diagnosis of diabetes. Data from 10,321 participants in the Atherosclerosis Risk in Communities (ARIC) Study who attended visit 4 (1996-1998) were analyzed. Prevalent self-reported diabetes was compared with reference definitions defined by fasting glucose and medication use obtained at visit 4. Incident self-reported diabetes was assessed during annual follow-up telephone calls and was compared with reference definitions defined by fasting glucose, hemoglobin A1c, and medication use obtained during an in-person visit attended by a subsample of participants (n = 1,738) in 2004-2005. The sensitivity of prevalent self-reported diabetes ranged from 58.5% to 70.8%, and specificity ranged from 95.6% to 96.8%, depending on the reference definition. Similarly, the sensitivity of incident self-reported diabetes ranged from 55.9% to 80.4%, and specificity ranged from 84.5% to 90.6%. Percent positive agreement of self-reported diabetes during 9 years of repeat assessments ranged from 92.7% to 95.4%. Both prevalent self-reported diabetes and incident self-reported diabetes were 84%-97% specific and 55%-80% sensitive as compared with reference definitions using glucose and medication criteria. Self-reported diabetes was >92% reliable over time.

  14. Associations between self-reported and objective physical environmental factors and use of a community rail-trail.

    Science.gov (United States)

    Troped, P J; Saunders, R P; Pate, R R; Reininger, B; Ureda, J R; Thompson, S J

    2001-02-01

    To effectively promote physical activIty, researchers and policy makers have advocated for greater use of environmental approaches, such as the construction of community paths and trails. However, research on the use of these facilities is limited. In this cross-sectional community study, we examined associations between self-reported and objective physical environmental variables and use of the Minuteman Bikeway (Arlington, MA) in a random sample of 413 adults. Sociodemographic and perceived environmental variables were measured with a mail survey during September 1998. Geographic information system (GIS) data were used to geocode survey respondents' homes and create three objective environmental variables: distance to the Bikeway, steep hill barrier, and a busy street barrier. In logistic models, age and female gender showed statistically significant inverse associations with Bikeway use over the previous 4-week period. Increases in self-reported (OR = 0.65) and GIS distance (OR = 0.57) were associated with decreased likelihood of Bikeway use. Absence of self-reported busy street (OR = 2.01) and GIS steep hill barriers (OR = 1.84) were associated with Bikeway use. Environmental barriers such as travel distance and hilly terrain should be considered when planning community trails. A better understanding of such factors may lead to more effective promotion of trail use. Copyright 2001 American Health Foundation and Academic Press.

  15. A Community Health Worker Intervention for Diabetes Self-Management Among the Tz'utujil Maya of Guatemala.

    Science.gov (United States)

    Micikas, Mary; Foster, Jennifer; Weis, Allison; Lopez-Salm, Alyse; Lungelow, Danielle; Mendez, Pedro; Micikas, Ashley

    2015-07-01

    Despite the high prevalence of diabetes in rural Guatemala, there is little education in diabetes self-management, particularly among the indigenous population. To address this need, a culturally relevant education intervention for diabetic patients was developed and implemented in two rural communities in Guatemala. An evaluative research project was designed to investigate if the structured, community-led diabetes self-management intervention improved selected health outcomes for participants. A one-group, pretest-posttest design was used to evaluate the effectiveness of the educational intervention by comparing measures of health, knowledge, and behavior in patients pre- and postintervention. A survey instrument assessed health beliefs and practices and hemoglobin A1c (HgA1c) measured blood glucose levels at baseline and 4 months post initiation of intervention (n = 52). There was a significant decrease (1.2%) in the main outcome measure, mean HgA1c from baseline (10.1%) and follow-up (8.9%; p = .001). Other survey findings were not statistically significant. This study illustrates that a culturally specific, diabetes self-management program led by community health workers may reduce HgA1c levels in rural populations of Guatemala. However, as a random sample was not feasible for this study, this finding should be interpreted with caution. Limitations unique to the setting and patient population are discussed in this article. © 2014 Society for Public Health Education.

  16. Protection enhances community and habitat stability: evidence from a mediterranean marine protected area.

    Science.gov (United States)

    Fraschetti, Simonetta; Guarnieri, Giuseppe; Bevilacqua, Stanislao; Terlizzi, Antonio; Boero, Ferdinando

    2013-01-01

    Rare evidences support that Marine Protected Areas (MPAs) enhance the stability of marine habitats and assemblages. Based on nine years of observation (2001-2009) inside and outside a well managed MPA, we assessed the potential of conservation and management actions to modify patterns of spatial and/or temporal variability of Posidonia oceanica meadows, the lower midlittoral and the shallow infralittoral rock assemblages. Significant differences in both temporal variations and spatial patterns were observed between protected and unprotected locations. A lower temporal variability in the protected vs. unprotected assemblages was found in the shallow infralittoral, demonstrating that, at least at local scale, protection can enhance community stability. Macrobenthos with long-lived and relatively slow-growing invertebrates and structurally complex algal forms were homogeneously distributed in space and went through little fluctuations in time. In contrast, a mosaic of disturbed patches featured unprotected locations, with small-scale shifts from macroalgal stands to barrens, and harsh temporal variations between the two states. Opposite patterns of spatial and temporal variability were found for the midlittoral assemblages. Despite an overall clear pattern of seagrass regression through time, protected meadows showed a significantly higher shoot density than unprotected ones, suggesting a higher resistance to local human activities. Our results support the assumption that the exclusion/management of human activities within MPAs enhance the stability of the structural components of protected marine systems, reverting or arresting threat-induced trajectories of change.

  17. Therapeutic Community Effectiveness on Self-Esteem and Relapse Rate among Drug Users

    Directory of Open Access Journals (Sweden)

    Mosayyeb Yarmohammadi-Vasel

    2012-04-01

    Full Text Available Objective: In recent years, the Therapeutic Community(TC has become a widespread treatment alternative for drug addicts. TC have been widely studied with emphasis on thair effectiveness. The aims of the present study was to examined effectiveness of TC on self esteem and decrease of relapse. Materials & Methods: Research Statistics universe constitutes of all the substance abusers who have come to the TC centers of Tehran and Mashad. samples is chosen as stratified sampling of the cities of Tehran & Mashad. This study conducted among 165 substance abuser, examined their drug use 2 years. The study utilized a quasi-experimental design with one group, clients were tested at 3 points in time pretest (at admission time, posttest (3-6 months after treatment and 1-year Follo-up (1-year after treatment using the self esteem questionnaire. Results: The findings show that (a about half (50% the clients were clean at follow-up (b significant linear increases on self esteem After 3 to 6 months of treatment(P<0.05. Conclusion: This study provides evidence that TC could effective approach to increases on self esteem and decrease of relapse.

  18. Community energy self-reliance

    Science.gov (United States)

    1980-07-01

    Goals of a workshop/conference on community renewable energy systems are: (1) to encourage decentralization in attacking energy problems, (2) to show how renewable energy can meet community goals, (3) to present examples of successful projects, (4) to discuss the planning and management of renewable energy systems, (5) to identify sources of financial support, (6) to share legal strategies, and (7) to examine utility roles.

  19. Preparation of Salicylic Acid Loaded Nanostructured Lipid Carriers Using Box-Behnken Design: Optimization, Characterization and Physicochemical Stability.

    Science.gov (United States)

    Pantub, Ketrawee; Wongtrakul, Paveena; Janwitayanuchit, Wicharn

    2017-01-01

    Nanostructured lipid carriers loaded salicylic acid (NLCs-SA) were developed and optimized by using the design of experiment (DOE). Box-Behnken experimental design of 3-factor, 3-level was applied for optimization of nanostructured lipid carriers prepared by emulsification method. The independent variables were total lipid concentration (X 1 ), stearic acid to Lexol ® GT-865 ratio (X 2 ) and Tween ® 80 concentration (X 3 ) while the particle size was a dependent variable (Y). Box-Behnken design could create 15 runs by setting response optimizer as minimum particle size. The optimized formulation consists of 10% of total lipid, a mixture of stearic acid and capric/caprylic triglyceride at a 4:1 ratio, and 25% of Tween ® 80 which the formulation was applied in order to prepare in both loaded and unloaded salicylic acid. After preparation for 24 hours, the particle size of loaded and unloaded salicylic acid was 189.62±1.82 nm and 369.00±3.37 nm, respectively. Response surface analysis revealed that the amount of total lipid is a main factor which could affect the particle size of lipid carriers. In addition, the stability studies showed a significant change in particle size by time. Compared to unloaded nanoparticles, the addition of salicylic acid into the particles resulted in physically stable dispersion. After 30 days, sedimentation of unloaded lipid carriers was clearly observed. Absolute values of zeta potential of both systems were in the range of 3 to 18 mV since non-ionic surfactant, Tween ® 80, providing steric barrier was used. Differential thermograms indicated a shift of endothermic peak from 55°C for α-crystal form in freshly prepared samples to 60°C for β´-crystal form in storage samples. It was found that the presence of capric/caprylic triglyceride oil could enhance encapsulation efficiency up to 80% and facilitate stability of the particles.

  20. Enhancing Self Presentation through Drama at a Community College: Rehearsing for the Job Interview

    Science.gov (United States)

    Socas, John

    2014-01-01

    In these times of economic uncertainty, successful performance at job interviews has become increasingly important in order to obtain employment. This study examines the experiences of students at an urban community college in an intervention where drama embodied with reflection is used to enhance professionally relevant self-presentation skills.…