WorldWideScience

Sample records for network sensitivity experiments

  1. Parameter Sensitivity Analysis on Deformation of Composite Soil-Nailed Wall Using Artificial Neural Networks and Orthogonal Experiment

    Directory of Open Access Journals (Sweden)

    Jianbin Hao

    2014-01-01

    Full Text Available Based on the back-propagation algorithm of artificial neural networks (ANNs, this paper establishes an intelligent model, which is used to predict the maximum lateral displacement of composite soil-nailed wall. Some parameters, such as soil cohesive strength, soil friction angle, prestress of anchor cable, soil-nail spacing, soil-nail diameter, soil-nail length, and other factors, are considered in the model. Combined with the in situ test data of composite soil-nail wall reinforcement engineering, the network is trained and the errors are analyzed. Thus it is demonstrated that the method is applicable and feasible in predicting lateral displacement of excavation retained by composite soil-nailed wall. Extended calculations are conducted by using the well-trained intelligent forecast model. Through application of orthogonal table test theory, 25 sets of tests are designed to analyze the sensitivity of factors affecting the maximum lateral displacement of composite soil-nailing wall. The results show that the sensitivity of factors affecting the maximum lateral displacement of composite soil nailing wall, in a descending order, are prestress of anchor cable, soil friction angle, soil cohesion strength, soil-nail spacing, soil-nail length, and soil-nail diameter. The results can provide important reference for the same reinforcement engineering.

  2. Sensitive Dependence of Optimal Network Dynamics on Network Structure

    Directory of Open Access Journals (Sweden)

    Takashi Nishikawa

    2017-11-01

    Full Text Available The relation between network structure and dynamics is determinant for the behavior of complex systems in numerous domains. An important long-standing problem concerns the properties of the networks that optimize the dynamics with respect to a given performance measure. Here, we show that such optimization can lead to sensitive dependence of the dynamics on the structure of the network. Specifically, using diffusively coupled systems as examples, we demonstrate that the stability of a dynamical state can exhibit sensitivity to unweighted structural perturbations (i.e., link removals and node additions for undirected optimal networks and to weighted perturbations (i.e., small changes in link weights for directed optimal networks. As mechanisms underlying this sensitivity, we identify discontinuous transitions occurring in the complement of undirected optimal networks and the prevalence of eigenvector degeneracy in directed optimal networks. These findings establish a unified characterization of networks optimized for dynamical stability, which we illustrate using Turing instability in activator-inhibitor systems, synchronization in power-grid networks, network diffusion, and several other network processes. Our results suggest that the network structure of a complex system operating near an optimum can potentially be fine-tuned for a significantly enhanced stability compared to what one might expect from simple extrapolation. On the other hand, they also suggest constraints on how close to the optimum the system can be in practice. Finally, the results have potential implications for biophysical networks, which have evolved under the competing pressures of optimizing fitness while remaining robust against perturbations.

  3. Measuring Road Network Vulnerability with Sensitivity Analysis

    Science.gov (United States)

    Jun-qiang, Leng; Long-hai, Yang; Liu, Wei-yi; Zhao, Lin

    2017-01-01

    This paper focuses on the development of a method for road network vulnerability analysis, from the perspective of capacity degradation, which seeks to identify the critical infrastructures in the road network and the operational performance of the whole traffic system. This research involves defining the traffic utility index and modeling vulnerability of road segment, route, OD (Origin Destination) pair and road network. Meanwhile, sensitivity analysis method is utilized to calculate the change of traffic utility index due to capacity degradation. This method, compared to traditional traffic assignment, can improve calculation efficiency and make the application of vulnerability analysis to large actual road network possible. Finally, all the above models and calculation method is applied to actual road network evaluation to verify its efficiency and utility. This approach can be used as a decision-supporting tool for evaluating the performance of road network and identifying critical infrastructures in transportation planning and management, especially in the resource allocation for mitigation and recovery. PMID:28125706

  4. Father's brain is sensitive to childcare experiences.

    Science.gov (United States)

    Abraham, Eyal; Hendler, Talma; Shapira-Lichter, Irit; Kanat-Maymon, Yaniv; Zagoory-Sharon, Orna; Feldman, Ruth

    2014-07-08

    Although contemporary socio-cultural changes dramatically increased fathers' involvement in childrearing, little is known about the brain basis of human fatherhood, its comparability with the maternal brain, and its sensitivity to caregiving experiences. We measured parental brain response to infant stimuli using functional MRI, oxytocin, and parenting behavior in three groups of parents (n = 89) raising their firstborn infant: heterosexual primary-caregiving mothers (PC-Mothers), heterosexual secondary-caregiving fathers (SC-Fathers), and primary-caregiving homosexual fathers (PC-Fathers) rearing infants without maternal involvement. Results revealed that parenting implemented a global "parental caregiving" neural network, mainly consistent across parents, which integrated functioning of two systems: the emotional processing network including subcortical and paralimbic structures associated with vigilance, salience, reward, and motivation, and mentalizing network involving frontopolar-medial-prefrontal and temporo-parietal circuits implicated in social understanding and cognitive empathy. These networks work in concert to imbue infant care with emotional salience, attune with the infant state, and plan adequate parenting. PC-Mothers showed greater activation in emotion processing structures, correlated with oxytocin and parent-infant synchrony, whereas SC-Fathers displayed greater activation in cortical circuits, associated with oxytocin and parenting. PC-Fathers exhibited high amygdala activation similar to PC-Mothers, alongside high activation of superior temporal sulcus (STS) comparable to SC-Fathers, and functional connectivity between amygdala and STS. Among all fathers, time spent in direct childcare was linked with the degree of amygdala-STS connectivity. Findings underscore the common neural basis of maternal and paternal care, chart brain-hormone-behavior pathways that support parenthood, and specify mechanisms of brain malleability with caregiving

  5. Using Granular-Evidence-Based Adaptive Networks for Sensitivity Analysis

    OpenAIRE

    Vališevskis, A.

    2002-01-01

    This paper considers the possibility of using adaptive networks for sensitivity analysis. Adaptive network that processes fuzzy granules is described. The adaptive network training algorithm can be used for sensitivity analysis of decision making models. Furthermore, a case study concerning sensitivity analysis is described, which shows in what way the adaptive network can be used for sensitivity analysis.

  6. The stability of Boolean network with transmission sensitivity

    Science.gov (United States)

    Wang, Jiannan; Guo, Binghui; Wei, Wei; Mi, Zhilong; Yin, Ziqiao; Zheng, Zhiming

    2017-09-01

    Boolean network has been widely used in modeling biological systems and one of the key problems is its stability in response to small perturbations. Based on the hypothesis that the states of all nodes are homogenously updated, great progress has been made in previous works. In real biological networks, however, the updates of genes typically show much heterogeneity. To address such conditions, we introduce transmission sensitivity into Boolean network model. By the method of semi-annealed approximation, we illustrate that in a homogenous network, the critical condition of stability has no connection with its transmission sensitivity. As for heterogeneous networks, it reveals that correlations between network topology and transmission sensitivity can have profound effects on the its stability. This result shows a new mechanism that affects the stability of Boolean network, which could be used to control the dynamics in real biological systems.

  7. Laboratory Experiments for Network Security Instruction

    Science.gov (United States)

    Brustoloni, Jose Carlos

    2006-01-01

    We describe a sequence of five experiments on network security that cast students successively in the roles of computer user, programmer, and system administrator. Unlike experiments described in several previous papers, these experiments avoid placing students in the role of attacker. Each experiment starts with an in-class demonstration of an…

  8. Thermodynamics-based Metabolite Sensitivity Analysis in metabolic networks.

    Science.gov (United States)

    Kiparissides, A; Hatzimanikatis, V

    2017-01-01

    The increasing availability of large metabolomics datasets enhances the need for computational methodologies that can organize the data in a way that can lead to the inference of meaningful relationships. Knowledge of the metabolic state of a cell and how it responds to various stimuli and extracellular conditions can offer significant insight in the regulatory functions and how to manipulate them. Constraint based methods, such as Flux Balance Analysis (FBA) and Thermodynamics-based flux analysis (TFA), are commonly used to estimate the flow of metabolites through genome-wide metabolic networks, making it possible to identify the ranges of flux values that are consistent with the studied physiological and thermodynamic conditions. However, unless key intracellular fluxes and metabolite concentrations are known, constraint-based models lead to underdetermined problem formulations. This lack of information propagates as uncertainty in the estimation of fluxes and basic reaction properties such as the determination of reaction directionalities. Therefore, knowledge of which metabolites, if measured, would contribute the most to reducing this uncertainty can significantly improve our ability to define the internal state of the cell. In the present work we combine constraint based modeling, Design of Experiments (DoE) and Global Sensitivity Analysis (GSA) into the Thermodynamics-based Metabolite Sensitivity Analysis (TMSA) method. TMSA ranks metabolites comprising a metabolic network based on their ability to constrain the gamut of possible solutions to a limited, thermodynamically consistent set of internal states. TMSA is modular and can be applied to a single reaction, a metabolic pathway or an entire metabolic network. This is, to our knowledge, the first attempt to use metabolic modeling in order to provide a significance ranking of metabolites to guide experimental measurements. Copyright © 2016 International Metabolic Engineering Society. Published by Elsevier

  9. VNEC - A Virtual Network Experiment Controller

    Science.gov (United States)

    Gagnon, François; Dej, Tomas; Esfandiari, Babak

    This paper presents VNEC, a tool to specify and execute network experiments in a virtual environment. The user first formulates the network topology and then provides the tasks that should be performed by the computers together with their execution. Next, VNEC initializes the environment by powering up and configuring the virtual machines to match the desired network topology. Finally, commands are dispatched to the right virtual machines in the specified order. VNEC provides an environment for several types of research experiments such as virus propagation patterns and reactions of different targets against a given attack.

  10. Research on quasi-dynamic calibration model of plastic sensitive element based on neural networks

    Science.gov (United States)

    Wang, Fang; Kong, Deren; Yang, Lixia; Zhang, Zouzou

    2017-08-01

    Quasi-dynamic calibration accuracy of the plastic sensitive element depends on the accuracy of the fitting model between pressure and deformation. By using the excellent nonlinear mapping ability of RBF (Radial Basis Function) neural network, a calibration model is established which use the peak pressure as the input and use the deformation of the plastic sensitive element as the output in this paper. The calibration experiments of a batch of copper cylinders are carried out on the quasi-dynamic pressure calibration device, which pressure range is within the range of 200MPa to 700MPa. The experiment data are acquired according to the standard pressure monitoring system. The network train and study are done to quasi dynamic calibration model based on neural network by using MATLAB neural network toolbox. Taking the testing samples as the research object, the prediction accuracy of neural network model is compared with the exponential fitting model and the second-order polynomial fitting model. The results show that prediction of the neural network model is most close to the testing samples, and the accuracy of prediction model based on neural network is better than 0.5%, respectively one order higher than the second-order polynomial fitting model and two orders higher than the exponential fitting model. The quasi-dynamic calibration model between pressure peak and deformation of plastic sensitive element, which is based on neural network, provides important basis for creating higher accuracy quasi-dynamic calibration table.

  11. Enabling software defined networking experiments in networked critical infrastructures

    Directory of Open Access Journals (Sweden)

    Béla Genge

    2014-05-01

    Full Text Available Nowadays, the fact that Networked Critical Infrastructures (NCI, e.g., power plants, water plants, oil and gas distribution infrastructures, and electricity grids, are targeted by significant cyber threats is well known. Nevertheless, recent research has shown that specific characteristics of NCI can be exploited in the enabling of more efficient mitigation techniques, while novel techniques from the field of IP networks can bring significant advantages. In this paper we explore the interconnection of NCI communication infrastructures with Software Defined Networking (SDN-enabled network topologies. SDN provides the means to create virtual networking services and to implement global networking decisions. It relies on OpenFlow to enable communication with remote devices and has been recently categorized as the “Next Big Technology”, which will revolutionize the way decisions are implemented in switches and routers. Therefore, the paper documents the first steps towards enabling an SDN-NCI and presents the impact of a Denial of Service experiment over traffic resulting from an XBee sensor network which is routed across an emulated SDN network.

  12. NETWORK UNIVERSITIES: INTERNATIONAL EXPERIENCE AND TRENDS

    Directory of Open Access Journals (Sweden)

    Г А Краснова

    2016-12-01

    Full Text Available The article is devoted to networking foreign universities, in particular, it considers the experience of cooperation of Vietnamese and Chinese universities with the leading universities of the world and the implementation of joint educational projects. The article deals with the basic characteristics of university networks that emerged in the last decade in developing countries. The authors analyzed the model, sources of financing, the organization of educational process, teaching of languages and the number of students in the university network, as well as the main mechanisms that allow open network structure of education in different countries of the world. The authors also address the main reasons for encouraging networking of foreign universities.

  13. Distributed control network for optogenetic experiments

    Science.gov (United States)

    Kasprowicz, G.; Juszczyk, B.; Mankiewicz, L.

    2014-11-01

    Nowadays optogenetic experiments are constructed to examine social behavioural relations in groups of animals. A novel concept of implantable device with distributed control network and advanced positioning capabilities is proposed. It is based on wireless energy transfer technology, micro-power radio interface and advanced signal processing.

  14. The Deep Impact Network Experiment Operations Center

    Science.gov (United States)

    Torgerson, J. Leigh; Clare, Loren; Wang, Shin-Ywan

    2009-01-01

    Delay/Disruption Tolerant Networking (DTN) promises solutions in solving space communications challenges arising from disconnections as orbiters lose line-of-sight with landers, long propagation delays over interplanetary links, and other phenomena. DTN has been identified as the basis for the future NASA space communications network backbone, and international standardization is progressing through both the Consultative Committee for Space Data Systems (CCSDS) and the Internet Engineering Task Force (IETF). JPL has developed an implementation of the DTN architecture, called the Interplanetary Overlay Network (ION). ION is specifically implemented for space use, including design for use in a real-time operating system environment and high processing efficiency. In order to raise the Technology Readiness Level of ION, the first deep space flight demonstration of DTN is underway, using the Deep Impact (DI) spacecraft. Called the Deep Impact Network (DINET), operations are planned for Fall 2008. An essential component of the DINET project is the Experiment Operations Center (EOC), which will generate and receive the test communications traffic as well as "out-of-DTN band" command and control of the DTN experiment, store DTN flight test information in a database, provide display systems for monitoring DTN operations status and statistics (e.g., bundle throughput), and support query and analyses of the data collected. This paper describes the DINET EOC and its value in the DTN flight experiment and potential for further DTN testing.

  15. Estimation of parameter sensitivities for stochastic reaction networks

    KAUST Repository

    Gupta, Ankit

    2016-01-07

    Quantification of the effects of parameter uncertainty is an important and challenging problem in Systems Biology. We consider this problem in the context of stochastic models of biochemical reaction networks where the dynamics is described as a continuous-time Markov chain whose states represent the molecular counts of various species. For such models, effects of parameter uncertainty are often quantified by estimating the infinitesimal sensitivities of some observables with respect to model parameters. The aim of this talk is to present a holistic approach towards this problem of estimating parameter sensitivities for stochastic reaction networks. Our approach is based on a generic formula which allows us to construct efficient estimators for parameter sensitivity using simulations of the underlying model. We will discuss how novel simulation techniques, such as tau-leaping approximations, multi-level methods etc. can be easily integrated with our approach and how one can deal with stiff reaction networks where reactions span multiple time-scales. We will demonstrate the efficiency and applicability of our approach using many examples from the biological literature.

  16. An Experience in Dysgraphia: Sensitivity Training for Teachers.

    Science.gov (United States)

    Strudler, Ruth M.

    1995-01-01

    A sensitivity training session to help elementary-grade teachers better understand the experience of students with learning disabilities is suggested, using an altered alphabet in a standard second-grade lesson plan format. (DB)

  17. Belle-II Experiment Network Requirements

    Energy Technology Data Exchange (ETDEWEB)

    Asner, David [Pacific Northwest National Laboratory (PNNL), Richland, WA (United States); Bell, Greg [ESnet; Carlson, Tim [Pacific Northwest National Laboratory (PNNL), Richland, WA (United States); Cowley, David [Pacific Northwest National Laboratory (PNNL), Richland, WA (United States); Dart, Eli [ESnet; Erwin, Brock [Pacific Northwest National Laboratory (PNNL), Richland, WA (United States); Godang, Romulus [Univ. of South Alabama, Mobile, AL (United States); Hara, Takanori [High Energy Accelerator Research Organization (KEK), Tsukuba (Japan); Johnson, Jerry [Pacific Northwest National Laboratory (PNNL), Richland, WA (United States); Johnson, Ron [Univ. of Washington, Seattle, WA (United States); Johnston, Bill [ESnet; Dam, Kerstin Kleese-van [Pacific Northwest National Laboratory (PNNL), Richland, WA (United States); Kaneko, Toshiaki [High Energy Accelerator Research Organization (KEK), Tsukuba (Japan); Kubota, Yoshihiro [NII; Kuhr, Thomas [Karlsruhe Inst. of Technology (KIT) (Germany); McCoy, John [Pacific Northwest National Laboratory (PNNL), Richland, WA (United States); Miyake, Hideki [High Energy Accelerator Research Organization (KEK), Tsukuba (Japan); Monga, Inder [ESnet; Nakamura, Motonori [NII; Piilonen, Leo [Virginia Polytechnic Inst. and State Univ. (Virginia Tech), Blacksburg, VA (United States); Pordes, Ruth [Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States); Ray, Douglas [Pacific Northwest National Laboratory (PNNL), Richland, WA (United States); Russell, Richard [Pacific Northwest National Laboratory (PNNL), Richland, WA (United States); Schram, Malachi [Pacific Northwest National Laboratory (PNNL), Richland, WA (United States); Schroeder, Jim [Pacific Northwest National Laboratory (PNNL), Richland, WA (United States); Sevior, Martin [Univ. of Melbourne (Australia); Singh, Surya [Pacific Northwest National Laboratory (PNNL), Richland, WA (United States); Suzuki, Soh [High Energy Accelerator Research Organization (KEK), Tsukuba (Japan); Sasaki, Takashi [High Energy Accelerator Research Organization (KEK), Tsukuba (Japan); Williams, Jim [Indiana Univ., Bloomington, IN (United States)

    2013-05-28

    The Belle experiment, part of a broad-based search for new physics, is a collaboration of ~400 physicists from 55 institutions across four continents. The Belle detector is located at the KEKB accelerator in Tsukuba, Japan. The Belle detector was operated at the asymmetric electron-positron collider KEKB from 1999-2010. The detector accumulated more than 1 ab-1 of integrated luminosity, corresponding to more than 2 PB of data near 10 GeV center-of-mass energy. Recently, KEK has initiated a $400 million accelerator upgrade to be called SuperKEKB, designed to produce instantaneous and integrated luminosity two orders of magnitude greater than KEKB. The new international collaboration at SuperKEKB is called Belle II. The first data from Belle II/SuperKEKB is expected in 2015. In October 2012, senior members of the Belle-II collaboration gathered at PNNL to discuss the computing and neworking requirements of the Belle-II experiment with ESnet staff and other computing and networking experts. The day-and-a-half-long workshop characterized the instruments and facilities used in the experiment, the process of science for Belle-II, and the computing and networking equipment and configuration requirements to realize the full scientific potential of the collaboration's work.

  18. Sensitivity of surface meteorological analyses to observation networks

    Science.gov (United States)

    Tyndall, Daniel Paul

    A computationally efficient variational analysis system for two-dimensional meteorological fields is developed and described. This analysis approach is most efficient when the number of analysis grid points is much larger than the number of available observations, such as for large domain mesoscale analyses. The analysis system is developed using MATLAB software and can take advantage of multiple processors or processor cores. A version of the analysis system has been exported as a platform independent application (i.e., can be run on Windows, Linux, or Macintosh OS X desktop computers without a MATLAB license) with input/output operations handled by commonly available internet software combined with data archives at the University of Utah. The impact of observation networks on the meteorological analyses is assessed by utilizing a percentile ranking of individual observation sensitivity and impact, which is computed by using the adjoint of the variational surface assimilation system. This methodology is demonstrated using a case study of the analysis from 1400 UTC 27 October 2010 over the entire contiguous United States domain. The sensitivity of this approach to the dependence of the background error covariance on observation density is examined. Observation sensitivity and impact provide insight on the influence of observations from heterogeneous observing networks as well as serve as objective metrics for quality control procedures that may help to identify stations with significant siting, reporting, or representativeness issues.

  19. Learning in innovation networks: Some simulation experiments

    Science.gov (United States)

    Gilbert, Nigel; Ahrweiler, Petra; Pyka, Andreas

    2007-05-01

    According to the organizational learning literature, the greatest competitive advantage a firm has is its ability to learn. In this paper, a framework for modeling learning competence in firms is presented to improve the understanding of managing innovation. Firms with different knowledge stocks attempt to improve their economic performance by engaging in radical or incremental innovation activities and through partnerships and networking with other firms. In trying to vary and/or to stabilize their knowledge stocks by organizational learning, they attempt to adapt to environmental requirements while the market strongly selects on the results. The simulation experiments show the impact of different learning activities, underlining the importance of innovation and learning.

  20. Interoceptive Sensitivity and Self-Reports of Emotional Experience

    OpenAIRE

    Barrett, Lisa Feldman; Quigley, Karen S.; Bliss-Moreau, Eliza; Aronson, Keith R.

    2004-01-01

    People differ in the extent to which they emphasize feelings of activation or deactivation in their verbal reports of experienced emotion, termed arousal focus (AF). Two multimethod studies indicate that AF is linked to heightened interoceptive sensitivity (as measured by performance on a heartbeat detection task). People who were more sensitive to their heartbeats emphasized feelings of activation and deactivation when reporting their experiences of emotion over time more than did those who ...

  1. Social networks in education: an analysis of experience and perspective

    OpenAIRE

    Feschenko, A.

    2012-01-01

    The foreign and domestic experience of social networking and social media in learning process is analyzed. The perspectives of development of e-learning in the context of the educational potential of social networks are considered.

  2. Victimization experiences and the stabilization of victim sensitivity.

    Science.gov (United States)

    Gollwitzer, Mario; Süssenbach, Philipp; Hannuschke, Marianne

    2015-01-01

    People reliably differ in the extent to which they are sensitive to being victimized by others. Importantly, "victim sensitivity" predicts how people behave in social dilemma situations: Victim-sensitive individuals are less likely to trust others and more likely to behave uncooperatively-especially in socially uncertain situations. This pattern can be explained with the sensitivity to mean intentions (SeMI) model, according to which victim sensitivity entails a specific and asymmetric sensitivity to contextual cues that are associated with untrustworthiness. Recent research is largely in line with the model's prediction, but some issues have remained conceptually unresolved so far. For instance, it is unclear why and how victim sensitivity becomes a stable trait and which developmental and cognitive processes are involved in such stabilization. In the present article, we will discuss the psychological processes that contribute to a stabilization of victim sensitivity within persons, both across the life span ("ontogenetic stabilization") and across social situations ("actual-genetic stabilization"). Our theoretical framework starts from the assumption that experiences of being exploited threaten a basic need, the need to trust. This need is so fundamental that experiences that threaten it receive a considerable amount of attention and trigger strong affective reactions. Associative learning processes can then explain (a) how certain contextual cues (e.g., facial expressions) become conditioned stimuli that elicit equally strong responses, (b) why these contextual untrustworthiness cues receive much more attention than, for instance, trustworthiness cues, and (c) how these cues shape spontaneous social expectations (regarding other people's intentions). Finally, avoidance learning can explain why these cognitive processes gradually stabilize and become a trait: the trait which is referred to as victim sensitivity.

  3. Victimization Experiences and the Stabilization of Victim Sensitivity

    Directory of Open Access Journals (Sweden)

    Mario eGollwitzer

    2015-04-01

    Full Text Available People reliably differ in the extent to which they are sensitive to being victimized by others. Importantly, victim sensitivity predicts how people behave in social dilemma situations: Victim-sensitive individuals are less likely to trust others and more likely to behave uncooperatively - especially in socially uncertain situations. This pattern can be explained with the Sensitivity to Mean Intentions (SeMI model, according to which victim sensitivity entails a specific and asymmetric sensitivity to contextual cues that are associated with untrustworthiness. Recent research is largely in line with the model’s prediction, but some issues have remained conceptually unresolved so far. For instance, it is unclear why and how victim sensitivity becomes a stable trait and which developmental and cognitive processes are involved in such stabilization. In the present article, we will discuss the psychological processes that contribute to a stabilization of victim sensitivity within persons, both across the life span (ontogenetic stabilization and across social situations (actual-genetic stabilization. Our theoretical framework starts from the assumption that experiences of being exploited threaten a basic need, the need to trust. This need is so fundamental that experiences that threaten it receive a considerable amount of attention and trigger strong affective reactions. Associative learning processes can then explain (a how certain contextual cues (e.g., facial expressions become conditioned stimuli that elicit equally strong responses, (b why these contextual untrustworthiness cues receive much more attention than, for instance, trustworthiness cues, and (c how these cues shape spontaneous social expectations (regarding other people’s intentions. Finally, avoidance learning can explain why these cognitive processes gradually stabilize and become a trait: the trait which is referred to as victim sensitivity.

  4. Vantage sensitivity: individual differences in response to positive experiences.

    Science.gov (United States)

    Pluess, Michael; Belsky, Jay

    2013-07-01

    The notion that some people are more vulnerable to adversity as a function of inherent risk characteristics is widely embraced in most fields of psychology. This is reflected in the popularity of the diathesis-stress framework, which has received a vast amount of empirical support over the years. Much less effort has been directed toward the investigation of endogenous factors associated with variability in response to positive influences. One reason for the failure to investigate individual differences in response to positive experiences as a function of endogenous factors may be the absence of adequate theoretical frameworks. According to the differential-susceptibility hypothesis, individuals generally vary in their developmental plasticity regardless of whether they are exposed to negative or positive influences--a notion derived from evolutionary reasoning. On the basis of this now well-supported proposition, we advance herein the new concept of vantage sensitivity, reflecting variation in response to exclusively positive experiences as a function of individual endogenous characteristics. After distinguishing vantage sensitivity from theoretically related concepts of differential-susceptibility and resilience, we review some recent empirical evidence for vantage sensitivity featuring behavioral, physiological, and genetic factors as moderators of a wide range of positive experiences ranging from family environment and psychotherapy to educational intervention. Thereafter, we discuss genetic and environmental factors contributing to individual differences in vantage sensitivity, potential mechanisms underlying vantage sensitivity, and practical implications. 2013 APA, all rights reserved

  5. Effects of Port Congestion in the Gate Control List Scheduling of Time Sensitive Networks

    DEFF Research Database (Denmark)

    Kentis, Angelos Mimidis; Berger, Michael Stübert; Soler, José

    Time Sensitive Networking (TSN) can provide deterministic traffic behavior over Ethernet networks, for time sensitive traffic, whilst also bound the delay/jitter. To do so, the IEEE TSN working group introduced a network-wide transmission port scheduling mechanism. The duration of this schedule...

  6. Insulin sensitivity predicts brain network connectivity following a meal.

    Science.gov (United States)

    Ryan, John P; Karim, Helmet T; Aizenstein, Howard J; Helbling, Nicole L; Toledo, Frederico G S

    2018-01-12

    There is converging evidence that insulin plays a role in food-reward signaling in the brain and has effects on enhancing cognition. Little is known about how these effects are altered in individuals with insulin resistance. The present study was designed to identify the relationships between insulin resistance and functional brain connectivity following a meal. Eighteen healthy adults (7 male, 11 female, age: 41-57 years-old) completed a frequently-sampled intravenous glucose tolerance test to quantify insulin resistance. On separate days at least one week apart, a resting state functional magnetic resonance imaging scan was performed: once after a mixed-meal and once after a 12-h fast. Seed-based resting state connectivity of the caudate nucleus and eigenvector centrality were used to identify relationships between insulin resistance and functional brain connectivity. Individuals with greater insulin resistance displayed stronger connectivity within reward networks following a meal suggesting insulin was less able to suppress reward. Insulin resistance was negatively associated with eigenvector centrality in the dorsal anterior cingulate cortex following a meal. These data suggest that individuals with less sensitivity to insulin may fail to shift brain networks away from reward and toward cognitive control following a meal. This altered feedback loop could promote overeating and obesity. Copyright © 2018. Published by Elsevier Inc.

  7. Projected sensitivity of the SuperCDMS SNOLAB experiment

    Energy Technology Data Exchange (ETDEWEB)

    Agnese, R.; Anderson, A. J.; Aramaki, T.; Arnquist, I.; Baker, W.; Barker, D.; Basu Thakur, R.; Bauer, D. A.; Borgland, A.; Bowles, M. A.; Brink, P. L.; Bunker, R.; Cabrera, B.; Caldwell, D. O.; Calkins, R.; Cartaro, C.; Cerdeño, D. G.; Chagani, H.; Chen, Y.; Cooley, J.; Cornell, B.; Cushman, P.; Daal, M.; Di Stefano, P. C. F.; Doughty, T.; Esteban, L.; Fallows, S.; Figueroa-Feliciano, E.; Fritts, M.; Gerbier, G.; Ghaith, M.; Godfrey, G. L.; Golwala, S. R.; Hall, J.; Harris, H. R.; Hofer, T.; Holmgren, D.; Hong, Z.; Hoppe, E.; Hsu, L.; Huber, M. E.; Iyer, V.; Jardin, D.; Jastram, A.; Kelsey, M. H.; Kennedy, A.; Kubik, A.; Kurinsky, N. A.; Leder, A.; Loer, B.; Lopez Asamar, E.; Lukens, P.; Mahapatra, R.; Mandic, V.; Mast, N.; Mirabolfathi, N.; Moffatt, R. A.; Morales Mendoza, J. D.; Orrell, J. L.; Oser, S. M.; Page, K.; Page, W. A.; Partridge, R.; Pepin, M.; Phipps, A.; Poudel, S.; Pyle, M.; Qiu, H.; Rau, W.; Redl, P.; Reisetter, A.; Roberts, A.; Robinson, A. E.; Rogers, H. E.; Saab, T.; Sadoulet, B.; Sander, J.; Schneck, K.; Schnee, R. W.; Serfass, B.; Speller, D.; Stein, M.; Street, J.; Tanaka, H. A.; Toback, D.; Underwood, R.; Villano, A. N.; von Krosigk, B.; Welliver, B.; Wilson, J. S.; Wright, D. H.; Yellin, S.; Yen, J. J.; Young, B. A.; Zhang, X.; Zhao, X.

    2017-04-07

    SuperCDMS SNOLAB will be a next-generation experiment aimed at directly detecting low-mass (< 10 GeV/c$^2$) particles that may constitute dark matter by using cryogenic detectors of two types (HV and iZIP) and two target materials (germanium and silicon). The experiment is being designed with an initial sensitivity to nuclear recoil cross sections ~ 1 x 10$^{-43}$ cm$^2$ for a dark matter particle mass of 1 GeV/c$^2$, and with capacity to continue exploration to both smaller masses and better sensitivities. The phonon sensitivity of the HV detectors will be sufficient to detect nuclear recoils from sub-GeV dark matter. A detailed calibration of the detector response to low energy recoils will be needed to optimize running conditions of the HV detectors and to interpret their data for dark matter searches. Low-activity shielding, and the depth of SNOLAB, will reduce most backgrounds, but cosmogenically produced $^{3}$H and naturally occurring $^{32}$Si will be present in the detectors at some level. Even if these backgrounds are x10 higher than expected, the science reach of the HV detectors would be over three orders of magnitude beyond current results for a dark matter mass of 1 GeV/c$^2$. The iZIP detectors are relatively insensitive to variations in detector response and backgrounds, and will provide better sensitivity for dark matter particle masses (> 5 GeV/c$^2$). The mix of detector types (HV and iZIP), and targets (germanium and silicon), planned for the experiment, as well as flexibility in how the detectors are operated, will allow us to maximize the low-mass reach, and understand the backgrounds that the experiment will encounter. Upgrades to the experiment, perhaps with a variety of ultra-low-background cryogenic detectors, will extend dark matter sensitivity down to the "neutrino floor", where coherent scatters of solar neutrinos become a limiting background.

  8. Neutrino Oscillation Parameter Sensitivity in Future Long-Baseline Experiments

    Energy Technology Data Exchange (ETDEWEB)

    Bass, Matthew [Colorado State Univ., Fort Collins, CO (United States)

    2014-01-01

    The study of neutrino interactions and propagation has produced evidence for physics beyond the standard model and promises to continue to shed light on rare phenomena. Since the discovery of neutrino oscillations in the late 1990s there have been rapid advances in establishing the three flavor paradigm of neutrino oscillations. The 2012 discovery of a large value for the last unmeasured missing angle has opened the way for future experiments to search for charge-parity symmetry violation in the lepton sector. This thesis presents an analysis of the future sensitivity to neutrino oscillations in the three flavor paradigm for the T2K, NO A, LBNE, and T2HK experiments. The theory of the three flavor paradigm is explained and the methods to use these theoretical predictions to design long baseline neutrino experiments are described. The sensitivity to the oscillation parameters for each experiment is presented with a particular focus on the search for CP violation and the measurement of the neutrino mass hierarchy. The variations of these sensitivities with statistical considerations and experimental design optimizations taken into account are explored. The effects of systematic uncertainties in the neutrino flux, interaction, and detection predictions are also considered by incorporating more advanced simulations inputs from the LBNE experiment.

  9. Sex differences in how social networks and relationship quality influence experimental pain sensitivity

    National Research Council Canada - National Science Library

    Vigil, Jacob M; Rowell, Lauren N; Chouteau, Simone; Chavez, Alexandre; Jaramillo, Elisa; Neal, Michael; Waid, David

    2013-01-01

    This is the first study to examine how both structural and functional components of individuals' social networks may moderate the association between biological sex and experimental pain sensitivity...

  10. Synthetic Event Reconstruction Experiments for Defining Sensor Network Characteristics

    Energy Technology Data Exchange (ETDEWEB)

    Lundquist, J K; Kosovic, B; Belles, R

    2005-12-15

    An event reconstruction technology system has been designed and implemented at Lawrence Livermore National Laboratory (LLNL). This system integrates sensor observations, which may be sparse and/or conflicting, with transport and dispersion models via Bayesian stochastic sampling methodologies to characterize the sources of atmospheric releases of hazardous materials. We demonstrate the application of this event reconstruction technology system to designing sensor networks for detecting and responding to atmospheric releases of hazardous materials. The quantitative measure of the reduction in uncertainty, or benefit of a given network, can be utilized by policy makers to determine the cost/benefit of certain networks. Herein we present two numerical experiments demonstrating the utility of the event reconstruction methodology for sensor network design. In the first set of experiments, only the time resolution of the sensors varies between three candidate networks. The most ''expensive'' sensor network offers few advantages over the moderately-priced network for reconstructing the release examined here. The second set of experiments explores the significance of the sensors detection limit, which can have a significant impact on sensor cost. In this experiment, the expensive network can most clearly define the source location and source release rate. The other networks provide data insufficient for distinguishing between two possible clusters of source locations. When the reconstructions from all networks are aggregated into a composite plume, a decision-maker can distinguish the utility of the expensive sensor network.

  11. PIENU experiment at TRIUMF: A sensitive probe of new physics

    Science.gov (United States)

    Sher, A.; Aguilar-Arevalo, A.; Aoki, M.; Blecher, M.; Britton, D. I.; Bryman, D. A.; von Bruch, D.; Chen, S.; Comfort, J.; Ding, M.; Doria, L.; Gumplinger, P.; Hussein, A.; Igarashi, Y.; Ito, N.; Ito, S.; Kettell, S.; Kuno, Y.; Kurchaninov, L.; Littenberg, L.; Malbrunot, C.; Mischke, R.; Numao, T.; Sandorfi, A.; Sullivan, T.; Vavilov, D.; Yamada, K.; Yoshida, Y.

    2013-10-01

    A TRIUMF experiment, PIENU, which aims to measure the branching ratio of pion decays, R = Γ(π→eν+eνγ)/Γ(π→μν+μνγ) to a precision of 0.1% or better is described. Such a measurement provides the best test of electron-muon universality in weak interactions and is sensitive to an effective mass scale of up to 1000 TeV in new physics.

  12. Design of a Matching Network for a High-Sensitivity Broadband Magnetic Resonance Sounding Coil Sensor.

    Science.gov (United States)

    Zhang, Yang; Teng, Fei; Li, Suhang; Wan, Ling; Lin, Tingting

    2017-10-27

    The magnetic resonance sounding (MRS) technique is a non-invasive geophysical method that can provide unique insights into the hydrological properties of groundwater. The Cu coil sensor is the preferred choice for detecting the weak MRS signal because of its high sensitivity, low fabrication complexity and low cost. The tuned configuration was traditionally used for the MRS coil sensor design because of its high sensitivity and narrowband filtering. However, its narrow bandwidth may distort the MRS signals. To address this issue, a non-tuned design exhibiting a broad bandwidth has emerged recently, however, the sensitivity decreases as the bandwidth increases. Moreover, the effect of the MRS applications is often seriously influenced by power harmonic noises in the developed areas, especially low-frequency harmonics, resulting in saturation of the coil sensor, regardless of the tuned or non-tuned configuration. To solve the two aforementioned problems, we propose a matching network consisting of an LC broadband filter in parallel with a matching capacitor and provide a design for a coil sensor with a matching network (CSMN). The theoretical parameter calculations and the equivalent schematic of the CSMN with noise sources are investigated, and the sensitivity of the CSMN is evaluated by the Allan variance and the signal-to-noise ratio (SNR). Correspondingly, we constructed the CSMN with a 3 dB bandwidth, passband gain, normalized equivalent input noise and sensitivity (detection limit) of 1030 Hz, 4.6 dB, 1.78 nV/(Hz)(1/2) @ 2 kHz and 3 nV, respectively. Experimental tests in the laboratory show that the CSMN can not only improve the sensitivity, but also inhibit the signal distortion by suppressing power harmonic noises in the strong electromagnetic interference environment. Finally, a field experiment is performed with the CSMN to show a valid measurement of the signals of an MRS instrument system.

  13. Sensitivity and network topology in chemical reaction systems

    Science.gov (United States)

    Okada, Takashi; Mochizuki, Atsushi

    2017-08-01

    In living cells, biochemical reactions are catalyzed by specific enzymes and connect to one another by sharing substrates and products, forming complex networks. In our previous studies, we established a framework determining the responses to enzyme perturbations only from network topology, and then proved a theorem, called the law of localization, explaining response patterns in terms of network topology. In this paper, we generalize these results to reaction networks with conserved concentrations, which allows us to study any reaction system. We also propose network characteristics quantifying robustness. We compare E. coli metabolic network with randomly rewired networks, and find that the robustness of the E. coli network is significantly higher than that of the random networks.

  14. The Emergence of Synaesthesia in a Neuronal Network Model via Changes in Perceptual Sensitivity and Plasticity.

    Directory of Open Access Journals (Sweden)

    Oren Shriki

    2016-07-01

    Full Text Available Synaesthesia is an unusual perceptual experience in which an inducer stimulus triggers a percept in a different domain in addition to its own. To explore the conditions under which synaesthesia evolves, we studied a neuronal network model that represents two recurrently connected neural systems. The interactions in the network evolve according to learning rules that optimize sensory sensitivity. We demonstrate several scenarios, such as sensory deprivation or heightened plasticity, under which synaesthesia can evolve even though the inputs to the two systems are statistically independent and the initial cross-talk interactions are zero. Sensory deprivation is the known causal mechanism for acquired synaesthesia and increased plasticity is implicated in developmental synaesthesia. The model unifies different causes of synaesthesia within a single theoretical framework and repositions synaesthesia not as some quirk of aberrant connectivity, but rather as a functional brain state that can emerge as a consequence of optimising sensory information processing.

  15. Projected sensitivity of the SuperCDMS SNOLAB experiment

    Energy Technology Data Exchange (ETDEWEB)

    Agnese, R.; Anderson, A. J.; Aramaki, T.; Arnquist, I.; Baker, W.; Barker, D.; Basu Thakur, R.; Bauer, D. A.; Borgland, A.; Bowles, M. A.; Brink, P. L.; Bunker, R.; Cabrera, B.; Caldwell, D. O.; Calkins, R.; Cartaro, C.; Cerdeño, D. G.; Chagani, H.; Chen, Y.; Cooley, J.; Cornell, B.; Cushman, P.; Daal, M.; Di Stefano, P. C. F.; Doughty, T.; Esteban, L.; Fallows, S.; Figueroa-Feliciano, E.; Fritts, M.; Gerbier, G.; Ghaith, M.; Godfrey, G. L.; Golwala, S. R.; Hall, J.; Harris, H. R.; Hofer, T.; Holmgren, D.; Hong, Z.; Hoppe, E.; Hsu, L.; Huber, M. E.; Iyer, V.; Jardin, D.; Jastram, A.; Kelsey, M. H.; Kennedy, A.; Kubik, A.; Kurinsky, N. A.; Leder, A.; Loer, B.; Lopez Asamar, E.; Lukens, P.; Mahapatra, R.; Mandic, V.; Mast, N.; Mirabolfathi, N.; Moffatt, R. A.; Morales Mendoza, J. D.; Orrell, J. L.; Oser, S. M.; Page, K.; Page, W. A.; Partridge, R.; Pepin, M.; Phipps, A.; Poudel, S.; Pyle, M.; Qiu, H.; Rau, W.; Redl, P.; Reisetter, A.; Roberts, A.; Robinson, A. E.; Rogers, H. E.; Saab, T.; Sadoulet, B.; Sander, J.; Schneck, K.; Schnee, R. W.; Serfass, B.; Speller, D.; Stein, M.; Street, J.; Tanaka, H. A.; Toback, D.; Underwood, R.; Villano, A. N.; von Krosigk, B.; Welliver, B.; Wilson, J. S.; Wright, D. H.; Yellin, S.; Yen, J. J.; Young, B. A.; Zhang, X.; Zhao, X.

    2017-04-01

    SuperCDMS SNOLAB will be a next-generation experiment aimed at directly detecting low-mass particles (with masses ≤ 10 GeV/c^2) that may constitute dark matter by using cryogenic detectors of two types (HV and iZIP) and two target materials (germanium and silicon). The experiment is being designed with an initial sensitivity to nuclear recoil cross sections ~1×10^-43 cm^2 for a dark matter particle mass of 1 GeV/c^2, and with capacity to continue exploration to both smaller masses and better sensitivities. The phonon sensitivity of the HV detectors will be sufficient to detect nuclear recoils from sub-GeV dark matter. A detailed calibration of the detector response to low-energy recoils will be needed to optimize running conditions of the HV detectors and to interpret their data for dark matter searches. Low-activity shielding, and the depth of SNOLAB, will reduce most backgrounds, but cosmogenically produced H-3 and naturally occurring Si-32 will be present in the detectors at some level. Even if these backgrounds are 10 times higher than expected, the science reach of the HV detectors would be over 3 orders of magnitude beyond current results for a dark matter mass of 1 GeV/c^2. The iZIP detectors are relatively insensitive to variations in detector response and backgrounds, and will provide better sensitivity for dark matter particles with masses ≳5 GeV/c^2. The mix of detector types (HV and iZIP), and targets (germanium and silicon), planned for the experiment, as well as flexibility in how the detectors are operated, will allow us to maximize the low-mass reach, and understand the backgrounds that the experiment will encounter. Upgrades to the experiment, perhaps with a variety of ultra-low-background cryogenic detectors, will extend dark matter sensitivity down to the “neutrino floor,” where coherent scatters of solar neutrinos become a limiting background.

  16. Individual choices in dynamic networks: an experiment on social preferences.

    Directory of Open Access Journals (Sweden)

    Dennie van Dolder

    Full Text Available Game-theoretic models of network formation typically assume that people create relations so as to maximize their own outcome in the network. Recent experiments on network formation suggest that the assumption of self-interest might be unwarranted and that social preferences, such as altruism and inequality aversion, play a role in the formation of social networks. We developed an experiment to systematically investigate whether people show preferences for outcomes of others during network formation. We find that such preferences play a role when network decisions degenerate to simple two-person decision tasks. In more complex environments, however, we find little evidence for social preferences as a significant decision criterion. Furthermore, we find some evidence for farsighted behavior in network formation.

  17. Estimating the Capacity of Urban Transportation Networks with an Improved Sensitivity Based Method

    Directory of Open Access Journals (Sweden)

    Muqing Du

    2015-01-01

    Full Text Available The throughput of a given transportation network is always of interest to the traffic administrative department, so as to evaluate the benefit of the transportation construction or expansion project before its implementation. The model of the transportation network capacity formulated as a mathematic programming with equilibrium constraint (MPEC well defines this problem. For practical applications, a modified sensitivity analysis based (SAB method is developed to estimate the solution of this bilevel model. The high-efficient origin-based (OB algorithm is extended for the precise solution of the combined model which is integrated in the network capacity model. The sensitivity analysis approach is also modified to simplify the inversion of the Jacobian matrix in large-scale problems. The solution produced in every iteration of SAB is restrained to be feasible to guarantee the success of the heuristic search. From the numerical experiments, the accuracy of the derivatives for the linear approximation could significantly affect the converging of the SAB method. The results also show that the proposed method could obtain good suboptimal solutions from different starting points in the test examples.

  18. Creating legitimacy in water governance networks through complexity sensitive management

    NARCIS (Netherlands)

    J. Edelenbos (Jurian); I.F. van Meerkerk (Ingmar); E-H. Klijn (Erik-Hans)

    2013-01-01

    markdownabstractNetwork management is of major importance for the functioning and the performance of governance networks, including their democratic legitimacy (see for example Koppenjan and Klijn, 2004; Edelenbos & Klijn, 2006; Klijn et al., 2010; Meier & O’Toole, 2001, 2007). Network management is

  19. College students' social networking experiences on Facebook

    National Research Council Canada - National Science Library

    Pempek, Tiffany A; Yermolayeva, Yevdokiya A; Calvert, Sandra L

    2009-01-01

    ... networking site, Facebook. At the end of the week, they also completed a follow-up survey. Results indicated that students use Facebook approximately 30 min throughout the day as part of their daily routine...

  20. Sensitivity analysis of critical experiments with evaluated nuclear data libraries

    Energy Technology Data Exchange (ETDEWEB)

    Fujiwara, D.; Kosaka, S. [Tepco Systems Corporation, Nuclear Engineering Dept., Tokyo (Japan)

    2008-07-01

    Criticality benchmark testing was performed with evaluated nuclear data libraries for thermal, low-enriched uranium fuel rod applications. C/E values for k{sub eff} were calculated with the continuous-energy Monte Carlo code MVP2 and its libraries generated from Endf/B-VI.8, Endf/B-VII.0, JENDL-3.3 and JEFF-3.1. Subsequently, the observed k{sub eff} discrepancies between libraries were decomposed to specify the source of difference in the nuclear data libraries using sensitivity analysis technique. The obtained sensitivity profiles are also utilized to estimate the adequacy of cold critical experiments to the boiling water reactor under hot operating condition. (authors)

  1. Sensitivity analysis of linear programming problem through a recurrent neural network

    Science.gov (United States)

    Das, Raja

    2017-11-01

    In this paper we study the recurrent neural network for solving linear programming problems. To achieve optimality in accuracy and also in computational effort, an algorithm is presented. We investigate the sensitivity analysis of linear programming problem through the neural network. A detailed example is also presented to demonstrate the performance of the recurrent neural network.

  2. MUMAL2: Improving sensitivity in shotgun proteomics using cost sensitive artificial neural networks and a threshold selector algorithm.

    Science.gov (United States)

    Cerqueira, Fabio Ribeiro; Ricardo, Adilson Mendes; de Paiva Oliveira, Alcione; Graber, Armin; Baumgartner, Christian

    2016-12-15

    This work presents a machine learning strategy to increase sensitivity in tandem mass spectrometry (MS/MS) data analysis for peptide/protein identification. MS/MS yields thousands of spectra in a single run which are then interpreted by software. Most of these computer programs use a protein database to match peptide sequences to the observed spectra. The peptide-spectrum matches (PSMs) must also be assessed by computational tools since manual evaluation is not practicable. The target-decoy database strategy is largely used for error estimation in PSM assessment. However, in general, that strategy does not account for sensitivity. In a previous study, we proposed the method MUMAL that applies an artificial neural network to effectively generate a model to classify PSMs using decoy hits with increased sensitivity. Nevertheless, the present approach shows that the sensitivity can be further improved with the use of a cost matrix associated with the learning algorithm. We also demonstrate that using a threshold selector algorithm for probability adjustment leads to more coherent probability values assigned to the PSMs. Our new approach, termed MUMAL2, provides a two-fold contribution to shotgun proteomics. First, the increase in the number of correctly interpreted spectra in the peptide level augments the chance of identifying more proteins. Second, the more appropriate PSM probability values that are produced by the threshold selector algorithm impact the protein inference stage performed by programs that take probabilities into account, such as ProteinProphet. Our experiments demonstrate that MUMAL2 reached around 15% of improvement in sensitivity compared to the best current method. Furthermore, the area under the ROC curve obtained was 0.93, demonstrating that the probabilities generated by our model are in fact appropriate. Finally, Venn diagrams comparing MUMAL2 with the best current method show that the number of exclusive peptides found by our method was

  3. The Design, Experience and Practice of Networked Learning

    DEFF Research Database (Denmark)

    Gleerup, Janne; Heilesen, Simon; Helms, Niels Henrik

    2014-01-01

    . The Design, Experience and Practice of Networked Learning will prove indispensable reading for researchers, teachers, consultants, and instructional designers in higher and continuing education; for those involved in staff and educational development, and for those studying post graduate qualifications...... in learning and teaching. This, the second volume in the Springer Book Series on Researching Networked Learning, is based on a selection of papers presented at the 2012 Networked Learning Conference held in Maastricht, The Netherlands....

  4. Improving User Experience of Internet Services in Cellular Networks

    OpenAIRE

    Klockar, Annika

    2015-01-01

    The Internet has grown enormously since the introduction of the World Wide Web in the early 90's. The evolution and wide spread deployment of cellular networks have contributed to make the Internet accessible to more people in more places. The cellular networks of today offer data rates high enough for most Internet services. Even so, the service quality experienced by the users is often lower than in wired networks. The performance of TCP has a large impact on user experience. Therefore, we ...

  5. Network Experiences Lead to the Adaption of a Firm’s Network Competence

    Directory of Open Access Journals (Sweden)

    Bianka Kühne

    2011-12-01

    Full Text Available Networks become increasingly important as external sources of innovation for firms. Through networks firms get incontact with different actors with whom they can exchange information and collaborate. A firm’s ability to be asuccessful network actor depends on its network competence. This term can be defined as having the necessaryknowledge, skills and qualifications for networking as well as using them effectively. In this paper we investigate thelink between a firm’s network competence and the benefits resulting from it in a two‐way direction. First, thenetwork competence of the firm facilitates the adoption of information from other network actors which may leadto innovation success. Second the perceived network benefits shall in their turn influence the network competenceof the firm. Consequently, firms will adapt their network strategy corresponding their experiences. The objective ofthis paper is to investigate the dynamics of networking and its influence on the firm’s network competence. For thisexploratory research 3 Belgian networks are examined. In‐depth interviews are used in combination with semistructuredinterview guides to conduct the research. Our results indicate that some firms perceive benefits fromtheir network efforts, for others it is more a burden. Furthermore, in some of our cases we found that positiveexperiences with clear benefits motivate the firm to enhance its network competence. This is illustrated by the factthat collaborations are more frequently initiated, trust is more easily build, firms are more open to communicateinformation and the confidentiality threshold is overcome.

  6. Social Software: Participants' Experience Using Social Networking for Learning

    Science.gov (United States)

    Batchelder, Cecil W.

    2010-01-01

    Social networking tools used in learning provides instructional design with tools for transformative change in education. This study focused on defining the meanings and essences of social networking through the lived common experiences of 7 college students. The problem of the study was a lack of learner voice in understanding the value of social…

  7. Loss Performance Modeling for Hierarchical Heterogeneous Wireless Networks With Speed-Sensitive Call Admission Control

    DEFF Research Database (Denmark)

    Huang, Qian; Huang, Yue-Cai; Ko, King-Tim

    2011-01-01

    A hierarchical overlay structure is an alternative solution that integrates existing and future heterogeneous wireless networks to provide subscribers with better mobile broadband services. Traffic loss performance in such integrated heterogeneous networks is necessary for an operator's network...... dimensioning and planning. This paper investigates the computationally efficient loss performance modeling for multiservice in hierarchical heterogeneous wireless networks. A speed-sensitive call admission control (CAC) scheme is considered in our model to assign overflowed calls to appropriate tiers...

  8. College students' social networking experiences on Facebook

    National Research Council Canada - National Science Library

    Pempek, Tiffany A; Yermolayeva, Yevdokiya A; Calvert, Sandra L

    2009-01-01

    ... photos online. In the spring of 2006, Nielsen//NetRatings (2006) reported that the top 10 social networking sites in the U.S. grew in number of users from 46.8 million to 68.8 million during the previous year. These sites reveal important information about how adolescents and young adults are interacting with one another in the information ...

  9. Design sensitivity and statistical power in acceptability judgment experiments

    Directory of Open Access Journals (Sweden)

    Jon Sprouse

    2017-02-01

    Full Text Available Previous investigations into the validity of acceptability judgment data have focused almost exclusively on 'type I errors '(or false positives because of the consequences of such errors for syntactic theories (Sprouse & Almeida 2012; Sprouse et al. 2013. The current study complements these previous studies by systematically investigating the 'type II error rate '(false negatives, or equivalently, the 'statistical power', of a wide cross-section of possible acceptability judgment experiments. Though type II errors have historically been assumed to be less costly than type I errors, the dynamics of scientific publishing mean that high type II error rates (i.e., studies with low statistical power can lead to increases in type I error rates in a given field of study. We present a set of experiments and resampling simulations to estimate statistical power for four tasks (forced-choice, Likert scale, magnitude estimation, and yes-no, 50 effect sizes instantiated by real phenomena, sample sizes from 5 to 100 participants, and two approaches to statistical analysis (null hypothesis and Bayesian. Our goals are twofold (i to provide a fuller picture of the status of acceptability judgment data in syntax, and (ii to provide detailed information that syntacticians can use to design and evaluate the sensitivity of acceptability judgment experiments in their own research.

  10. Context-sensitive data integration and prediction of biological networks

    National Research Council Canada - National Science Library

    Myers, Chad L; Troyanskaya, Olga G

    2007-01-01

    Motivation: Several recent methods have addressed the problem of heterogeneous data integration and network prediction by modeling the noise inherent in high-throughput genomic datasets, which can dramatically...

  11. The Distributed Unattended Networked Sensors Field Experiment

    National Research Council Canada - National Science Library

    Sim, Leng

    2000-01-01

    .... Army Research Laboratory (ARL) regularly conducts field experiments to demonstrate and evaluate real-time performance of the acoustic sensor test bed and to collect signature data of new targets for an ARL acoustic and seismic database...

  12. Sensitivity of the ATLAS Experiment to Extra Dimensions

    CERN Document Server

    Gough Eschrich, I

    2006-01-01

    In the late nineties several authors suggested that the extra dimensions predicted by string theory might lead to observable effects at high energy colliders. The ATLAS experiment which will start taking data at the LHC in 2007 will be an excellent place to search for such effects. A large set of models within the ADD or the Randall Sundrum geometries has been studied in ATLAS. These models predict a variety of signatures: jets and missing energy from direct graviton production, high mass tails in dilepton and diphoton production due to virtual graviton exchange, production of Kaluza-Klein excitations of standard model particles, etc. The sensitivity of ATLAS to these signatures will be presented.

  13. IATA-Bayesian Network Model for Skin Sensitization Data

    Data.gov (United States)

    U.S. Environmental Protection Agency — Since the publication of the Adverse Outcome Pathway (AOP) for skin sensitization, there have been many efforts to develop systematic approaches to integrate the...

  14. Pathways, Networks, and Systems: Theory and Experiments

    Energy Technology Data Exchange (ETDEWEB)

    Joseph H. Nadeau; John D. Lambris

    2004-10-30

    The international conference provided a unique opportunity for theoreticians and experimenters to exchange ideas, strategies, problems, challenges, language and opportunities in both formal and informal settings. This dialog is an important step towards developing a deep and effective integration of theory and experiments in studies of systems biology in humans and model organisms.

  15. Global sensitivity analysis in stochastic simulators of uncertain reaction networks

    KAUST Repository

    Navarro, María

    2016-12-26

    Stochastic models of chemical systems are often subjected to uncertainties in kinetic parameters in addition to the inherent random nature of their dynamics. Uncertainty quantification in such systems is generally achieved by means of sensitivity analyses in which one characterizes the variability with the uncertain kinetic parameters of the first statistical moments of model predictions. In this work, we propose an original global sensitivity analysis method where the parametric and inherent variability sources are both treated through Sobol’s decomposition of the variance into contributions from arbitrary subset of uncertain parameters and stochastic reaction channels. The conceptual development only assumes that the inherent and parametric sources are independent, and considers the Poisson processes in the random-time-change representation of the state dynamics as the fundamental objects governing the inherent stochasticity. A sampling algorithm is proposed to perform the global sensitivity analysis, and to estimate the partial variances and sensitivity indices characterizing the importance of the various sources of variability and their interactions. The birth-death and Schlögl models are used to illustrate both the implementation of the algorithm and the richness of the proposed analysis method. The output of the proposed sensitivity analysis is also contrasted with a local derivative-based sensitivity analysis method classically used for this type of systems.

  16. Discovery and Protection of Sensitive Linkage Information for Online Social Networks Services

    Science.gov (United States)

    Zhang, Nan; Song, Min; Fu, Xinwen; Yu, Wei

    This paper investigates the problem of suppressing access to sensitive linkage information over data published by users of an online social network service. We unveil the potential threats by inferring linkage information from the user-published data, and suggest a class of data publishing schemes to enable distributed data publication by individual users but hide the sensitive information. Our hope is that this white paper shed lights on the future investigation of privacy-preserving online social network services.

  17. What Online Networks Offer: Online Network Compositions and Online Learning Experiences of Three Ethnic Groups

    NARCIS (Netherlands)

    Lecluijze, Susanne Elisabeth; de Haan, M.J.|info:eu-repo/dai/nl/074405624; Ünlüsoy, A.|info:eu-repo/dai/nl/322909309

    2015-01-01

    This exploratory study examines ethno-cultural diversity in youth ́s narratives regarding their online learning experiences while also investigating how these narratives can be understood from the analysis of their online network structure and composition. Based on ego-network data of 79 respondents

  18. Measuring Networking as an Outcome Variable in Undergraduate Research Experiences

    Science.gov (United States)

    Hanauer, David I.; Hatfull, Graham

    2015-01-01

    The aim of this paper is to propose, present, and validate a simple survey instrument to measure student conversational networking. The tool consists of five items that cover personal and professional social networks, and its basic principle is the self-reporting of degrees of conversation, with a range of specific discussion partners. The networking instrument was validated in three studies. The basic psychometric characteristics of the scales were established by conducting a factor analysis and evaluating internal consistency using Cronbach’s alpha. The second study used a known-groups comparison and involved comparing outcomes for networking scales between two different undergraduate laboratory courses (one involving a specific effort to enhance networking). The final study looked at potential relationships between specific networking items and the established psychosocial variable of project ownership through a series of binary logistic regressions. Overall, the data from the three studies indicate that the networking scales have high internal consistency (α = 0.88), consist of a unitary dimension, can significantly differentiate between research experiences with low and high networking designs, and are related to project ownership scales. The ramifications of the networking instrument for student retention, the enhancement of public scientific literacy, and the differentiation of laboratory courses are discussed. PMID:26538387

  19. Exploiting sensitivity analysis in Bayesian networks for consumer satisfaction study

    NARCIS (Netherlands)

    Jaronski, W.; Bloemer, J.M.M.; Vanhoof, K.; Wets, G.

    2004-01-01

    The paper presents an application of Bayesian network technology in a empirical customer satisfaction study. The findings of the study should provide insight as to the importance of product/service dimensions in terms of the strength of their influence on overall satisfaction. To this end we apply a

  20. Sensitivity of directed networks to the addition and pruning of edges and vertices

    Science.gov (United States)

    Goltsev, A. V.; Timár, G.; Mendes, J. F. F.

    2017-08-01

    Directed networks have various topologically different extensive components, in contrast to a single giant component in undirected networks. We study the sensitivity (response) of the sizes of these extensive components in directed complex networks to the addition and pruning of edges and vertices. We introduce the susceptibility, which quantifies this sensitivity. We show that topologically different parts of a directed network have different sensitivity to the addition and pruning of edges and vertices and, therefore, they are characterized by different susceptibilities. These susceptibilities diverge at the critical point of the directed percolation transition, signaling the appearance (or disappearance) of the giant strongly connected component in the infinite size limit. We demonstrate this behavior in randomly damaged real and synthetic directed complex networks, such as the World Wide Web, Twitter, the Caenorhabditis elegans neural network, directed Erdős-Rényi graphs, and others. We reveal a nonmonotonic dependence of the sensitivity to random pruning of edges or vertices in the case of C. elegans and Twitter that manifests specific structural peculiarities of these networks. We propose the measurements of the susceptibilities during the addition or pruning of edges and vertices as a new method for studying structural peculiarities of directed networks.

  1. Brain and Social Networks: Fundamental Building Blocks of Human Experience.

    Science.gov (United States)

    Falk, Emily B; Bassett, Danielle S

    2017-09-01

    How do brains shape social networks, and how do social ties shape the brain? Social networks are complex webs by which ideas spread among people. Brains comprise webs by which information is processed and transmitted among neural units. While brain activity and structure offer biological mechanisms for human behaviors, social networks offer external inducers or modulators of those behaviors. Together, these two axes represent fundamental contributors to human experience. Integrating foundational knowledge from social and developmental psychology and sociology on how individuals function within dyads, groups, and societies with recent advances in network neuroscience can offer new insights into both domains. Here, we use the example of how ideas and behaviors spread to illustrate the potential of multilayer network models. Copyright © 2017 Elsevier Ltd. All rights reserved.

  2. Understanding how social networking influences perceived satisfaction with conference experiences

    Science.gov (United States)

    van Riper, Carena J.; van Riper, Charles; Kyle, Gerard T.; Lee, Martha E.

    2013-01-01

    Social networking is a key benefit derived from participation in conferences that bind the ties of a professional community. Building social networks can lead to satisfactory experiences while furthering participants' long- and short-term career goals. Although investigations of social networking can lend insight into how to effectively engage individuals and groups within a professional cohort, this area has been largely overlooked in past research. The present study investigates the relationship between social networking and satisfaction with the 10th Biennial Conference of Research on the Colorado Plateau using structural equation modelling. Results partially support the hypothesis that three dimensions of social networking – interpersonal connections, social cohesion, and secondary associations – positively contribute to the performance of various conference attributes identified in two focus group sessions. The theoretical and applied contributions of this paper shed light on the social systems formed within professional communities and resource allocation among service providers.

  3. Social Network Mixing Patterns In Mergers & Acquisitions - A Simulation Experiment

    Directory of Open Access Journals (Sweden)

    Robert Fabac

    2011-01-01

    Full Text Available In the contemporary world of global business and continuously growing competition, organizations tend to use mergers and acquisitions to enforce their position on the market. The future organization’s design is a critical success factor in such undertakings. The field of social network analysis can enhance our uderstanding of these processes as it lets us reason about the development of networks, regardless of their origin. The analysis of mixing patterns is particularly useful as it provides an insight into how nodes in a network connect with each other. We hypothesize that organizational networks with compatible mixing patterns will be integrated more successfully. After conducting a simulation experiment, we suggest an integration model based on the analysis of network assortativity. The model can be a guideline for organizational integration, such as occurs in mergers and acquisitions.

  4. Test experience on an ultrareliable computer communication network

    Science.gov (United States)

    Abbott, L. W.

    1984-01-01

    The dispersed sensor processing mesh (DSPM) is an experimental, ultra-reliable, fault-tolerant computer communications network that exhibits an organic-like ability to regenerate itself after suffering damage. The regeneration is accomplished by two routines - grow and repair. This paper discusses the DSPM concept for achieving fault tolerance and provides a brief description of the mechanization of both the experiment and the six-node experimental network. The main topic of this paper is the system performance of the growth algorithm contained in the grow routine. The characteristics imbued to DSPM by the growth algorithm are also discussed. Data from an experimental DSPM network and software simulation of larger DSPM-type networks are used to examine the inherent limitation on growth time by the growth algorithm and the relationship of growth time to network size and topology.

  5. Neural network real time event selection for the DIRAC experiment

    CERN Document Server

    Kokkas, P; Tauscher, Ludwig; Vlachos, S

    2001-01-01

    The neural network first level trigger for the DIRAC experiment at CERN is presented. Both the neural network algorithm used and its actual hardware implementation are described. The system uses the fast plastic scintillator information of the DIRAC spectrometer. In 210 ns it selects events with two particles having low relative momentum. Such events are selected with an efficiency of more than 0.94. The corresponding rate reduction for background events is a factor of 2.5. (10 refs).

  6. Integrated Networks: National and International Online Experiences

    Directory of Open Access Journals (Sweden)

    Osvaldo Muniz-Solari

    2009-02-01

    Full Text Available There is an increasing impression among online geography educators that interaction can be developed based on specific teaching and learning methods. The authors developed a practical research study to investigate this issue. The study was based on advanced graduate courses in geography at Beijing Normal University and Texas State University. International interaction was complemented by online collaboration among the US local group. Both synchronous and asynchronous communication systems were used, which spanned two platforms. Results of this experience indicate that teaching and learning methods must be enhanced by a flexible online learning model and extensive organizational support in order to increase interaction and reach a certain level of cooperation.

  7. A context-sensitive trust model for online social networking

    CSIR Research Space (South Africa)

    Danny, MN

    2016-11-01

    Full Text Available of privacy attacks. In the quest to address this problem, this paper proposes a context-sensitive trust model. The proposed trust model was designed using fuzzy logic theory and implemented using MATLAB. Contrary to existing trust models, the context...

  8. Forecast Sensitivity and Observation Impact (FSOI) Inter-comparison Experiment

    Science.gov (United States)

    Mahajan, R.; Auligne, T.; Gelaro, R.; Langland, R.; Groff, D. N.; Hotta, D.

    2016-12-01

    Forecast Sensitivity and Observation Impact (FSOI) techniques provide a practical means to estimate the forecast impact of all assimilated observations for NWP systems. In this presentation, we describe direct comparisons of FSOI quantities between different NWP systems. A common "baseline" set of FSOI experimental parameters are applied for the time period December-February (DJF) 2014/2015. An adjoint-based FSOI approach (Langland and Baker, 2004) is applied for the NWP systems at NASA/GMAO, the Naval Research Laboratory (NRL), the UK Met Office (UKMet); where as an ensemble-based FSOI approach (Kalnay et al., 2012) is applied at the National Centers for Environmental Prediction (NCEP). The Japan Meteorological Agency (JMA) applies both the adjoint-based and ensemble-based FSOI capabilities, enabling a direct comparison between the two techniques. Given the aforementioned experiment, we plan to describe the differences in aggregated FSOI quantities between NWP systems for the relevant observing systems. Additionally, NWP system inter-comparisons of FSOI quantities for common observation subsets within the 3-month period will be presented. The comparisons of observation subsets will provide insight as to the extent to which the aggregate results are representative in both space and time.

  9. Prediction of the insulin sensitivity index using Bayesian networks

    DEFF Research Database (Denmark)

    Bøttcher, Susanne Gammelgaard; Dethlefsen, Claus

    The insulin sensitivity index () can be used in assessing the risk of developing type 2 diabetes. An intravenous study is used to determine using Bergmans minimal model. However, an intravenous study is time consuming and expensive and therefore not suitable for large scale epidemiological studie...... test instead of an intravenous study. The methodology is applied to a dataset with 187 patients. We find that the values from this study are highly correlated to the values determined from the intravenous study. S_I S_I S_I S_I S_I......The insulin sensitivity index () can be used in assessing the risk of developing type 2 diabetes. An intravenous study is used to determine using Bergmans minimal model. However, an intravenous study is time consuming and expensive and therefore not suitable for large scale epidemiological studies...

  10. Characterizing individual differences in reward sensitivity from the brain networks involved in response inhibition.

    Science.gov (United States)

    Fuentes-Claramonte, Paola; Ávila, César; Rodríguez-Pujadas, Aina; Costumero, Víctor; Ventura-Campos, Noelia; Bustamante, Juan Carlos; Rosell-Negre, Patricia; Barrós-Loscertales, Alfonso

    2016-01-01

    A "disinhibited" cognitive profile has been proposed for individuals with high reward sensitivity, characterized by increased engagement in goal-directed responses and reduced processing of negative or unexpected cues, which impairs adequate behavioral regulation after feedback in these individuals. This pattern is manifested through deficits in inhibitory control and/or increases in RT variability. In the present work, we aimed to test whether this profile is associated with the activity of functional networks during a stop-signal task using independent component analysis (ICA). Sixty-one participants underwent fMRI while performing a stop-signal task, during which a manual response had to be inhibited. ICA was used to mainly replicate the functional networks involved in the task (Zhang and Li, 2012): two motor networks involved in the go response, the left and right fronto-parietal networks for stopping, a midline error-processing network, and the default-mode network (DMN), which was further subdivided into its anterior and posterior parts. Reward sensitivity was mainly associated with greater activity of motor networks, reduced activity in the midline network during correct stop trials and, behaviorally, increased RT variability. All these variables explained 36% of variance of the SR scores. This pattern of associations suggests that reward sensitivity involves greater motor engagement in the dominant response, more distractibility and reduced processing of salient or unexpected events, which may lead to disinhibited behavior. Copyright © 2015 Elsevier Inc. All rights reserved.

  11. Metals Are Important Contact Sensitizers: An Experience from Lithuania

    Directory of Open Access Journals (Sweden)

    Kotryna Linauskienė

    2017-01-01

    Full Text Available Background. Metals are very frequent sensitizers causing contact allergy and allergic contact dermatitis worldwide; up-to-date data based on patch test results has proved useful for the identification of a problem. Objectives. In this retrospective study prevalence of contact allergy to metals (nickel, chromium, palladium, gold, cobalt, and titanium in Lithuania is analysed. Patients/Methods. Clinical and patch test data of 546 patients patch tested in 2014–2016, in Vilnius University Hospital Santariskiu Klinikos, was analysed and compared with previously published data. Results. Almost third of tested patients (29.56% were sensitized to nickel. Younger women were more often sensitized to nickel than older ones (36% versus 22.8%, p=0.0011. Women were significantly more often sensitized to nickel than men (33% versus 6.1%, p<0.0001. Younger patients were more often sensitized to cobalt (11.6% versus 5.7%, p=0.0183. Sensitization to cobalt was related to sensitization to nickel (p<0.0001. Face dermatitis and oral discomfort were related to gold allergy (28% versus 6.9% dermatitis of other parts, p<0.0001. Older patients were patch test positive to gold(I sodium thiosulfate statistically significantly more often than younger ones (44.44% versus 21.21%, p=0.0281. Conclusions. Nickel, gold, cobalt, and chromium are leading metal sensitizers in Lithuania. Cobalt sensitization is often accompanied by sensitization to nickel. Sensitivity rate to palladium and nickel indicates possible cross-reactivity. No sensitization to titanium was found.

  12. Application of design of experiments and artificial neural networks ...

    African Journals Online (AJOL)

    user

    Abstract. This paper discusses the use of Distance based optimal designs in the design of experiments (DOE) and artificial neural networks (ANN) in optimizing the stacking sequence for simply supported laminated composite plate under uniformly distributed load (UDL) for minimizing the deflections and stresses. A number ...

  13. Laboratory experiments on the regulation of European network industries

    NARCIS (Netherlands)

    Henze, B.

    2016-01-01

    The main objective of this thesis is to use economic laboratory experiments in order to evaluate the performance of regulatory schemes and market designs in addressing challenges encountered in the regulation of European network industries. Chapter 2 assesses whether regulatory holidays and Long

  14. Application of design of experiments and artificial neural networks ...

    African Journals Online (AJOL)

    This paper discusses the use of Distance based optimal designs in the design of experiments (DOE) and artificial neural networks (ANN) in optimizing the stacking sequence for simply supported laminated composite plate under uniformly distributed load (UDL) for minimizing the deflections and stresses. A number of finite ...

  15. Teaching Experience in University Students Using Social Networks

    Science.gov (United States)

    Alcántar, María del Rocío Carranza; Ballesteros, Nuria Salán; Torres, Claudia Islas; Padilla, Alma Azucena Jiménez; Barajas, Rosa Elena Legaspi

    2016-01-01

    Social networks, specifically Facebook and Twitter, are currently one of the most mainstream forms of media in the world. Yet, its educational use for the dissemination of knowledge is not significantly evident. Under this premise, this report is presented, considering an experience in which teachers and university-level students used these…

  16. Antagonistic Coevolution Drives Whack-a-Mole Sensitivity in Gene Regulatory Networks.

    Directory of Open Access Journals (Sweden)

    Jeewoen Shin

    2015-10-01

    Full Text Available Robustness, defined as tolerance to perturbations such as mutations and environmental fluctuations, is pervasive in biological systems. However, robustness often coexists with its counterpart, evolvability--the ability of perturbations to generate new phenotypes. Previous models of gene regulatory network evolution have shown that robustness evolves under stabilizing selection, but it is unclear how robustness and evolvability will emerge in common coevolutionary scenarios. We consider a two-species model of coevolution involving one host and one parasite population. By using two interacting species, key model parameters that determine the fitness landscapes become emergent properties of the model, avoiding the need to impose these parameters externally. In our study, parasites are modeled on species such as cuckoos where mimicry of the host phenotype confers high fitness to the parasite but lower fitness to the host. Here, frequent phenotype changes are favored as each population continually adapts to the other population. Sensitivity evolves at the network level such that point mutations can induce large phenotype changes. Crucially, the sensitive points of the network are broadly distributed throughout the network and continually relocate. Each time sensitive points in the network are mutated, new ones appear to take their place. We have therefore named this phenomenon "whack-a-mole" sensitivity, after a popular fun park game. We predict that this type of sensitivity will evolve under conditions of strong directional selection, an observation that helps interpret existing experimental evidence, for example, during the emergence of bacterial antibiotic resistance.

  17. Sex differences in how social networks and relationship quality influence experimental pain sensitivity.

    Science.gov (United States)

    Vigil, Jacob M; Rowell, Lauren N; Chouteau, Simone; Chavez, Alexandre; Jaramillo, Elisa; Neal, Michael; Waid, David

    2013-01-01

    This is the first study to examine how both structural and functional components of individuals' social networks may moderate the association between biological sex and experimental pain sensitivity. One hundred and fifty-two healthy adults (mean age = 22yrs., 53% males) were measured for cold pressor task (CPT) pain sensitivity (i.e., intensity ratings) and core aspects of social networks (e.g., proportion of friends vs. family, affection, affirmation, and aid). Results showed consistent sex differences in how social network structures and intimate relationship functioning modulated pain sensitivity. Females showed higher pain sensitivity when their social networks consisted of a higher proportion of intimate types of relationship partners (e.g., kin vs. non kin), when they had known their network partners for a longer period of time, and when they reported higher levels of logistical support from their significant other (e.g., romantic partner). Conversely, males showed distinct patterns in the opposite direction, including an association between higher levels of logistical support from one's significant other and lower CPT pain intensity. These findings show for the first time that the direction of sex differences in exogenous pain sensitivity is likely dependent on fundamental components of the individual's social environment. The utility of a social-signaling perspective of pain behaviors for examining, comparing, and interpreting individual and group differences in experimental and clinical pain reports is discussed.

  18. A Delay-Sensitive Connected Target Coverage Algorithm in Wireless Sensor Networks

    Directory of Open Access Journals (Sweden)

    Junbin Liang

    2014-01-01

    Full Text Available The issue of guaranteeing the network QoS (target coverage, network connectivity, etc. to maximize the lifetime in wireless sensor networks (WSNs has been widely studied in recent years. In some delay-sensitive sensor networks (fires, gas leaks, explosions, etc., sensor nodes must transmit their data to sink within a limited period to monitor the critical physical environment. In order to study connected target coverage in such delay-sensitive sensor networks, we are the first one to propose the Delay-Constraint Connected Target Coverage (DCCTC problem and study the following works specifically: 1 we model DCCTC problem as a Height Limited Maximum Cover Tree (HLMCT problem, and then give an upper bound on the network lifetime for HLMCT problem; 2 we develop a fast heuristic algorithm, named HLCWGC; 3 we study the performance of HLCWGC algorithm by comparing it with other existing algorithms improved to solve HLMCT problem. Simulation results show that HLCWGC algorithm can achieve a better performance than other improved algorithms in the delay- sensitive sensor networks.

  19. Measuring Networking as an Outcome Variable in Undergraduate Research Experiences.

    Science.gov (United States)

    Hanauer, David I; Hatfull, Graham

    2015-01-01

    The aim of this paper is to propose, present, and validate a simple survey instrument to measure student conversational networking. The tool consists of five items that cover personal and professional social networks, and its basic principle is the self-reporting of degrees of conversation, with a range of specific discussion partners. The networking instrument was validated in three studies. The basic psychometric characteristics of the scales were established by conducting a factor analysis and evaluating internal consistency using Cronbach's alpha. The second study used a known-groups comparison and involved comparing outcomes for networking scales between two different undergraduate laboratory courses (one involving a specific effort to enhance networking). The final study looked at potential relationships between specific networking items and the established psychosocial variable of project ownership through a series of binary logistic regressions. Overall, the data from the three studies indicate that the networking scales have high internal consistency (α = 0.88), consist of a unitary dimension, can significantly differentiate between research experiences with low and high networking designs, and are related to project ownership scales. The ramifications of the networking instrument for student retention, the enhancement of public scientific literacy, and the differentiation of laboratory courses are discussed. © 2015 D. I. Hanauer and G. Hatfull. CBE—Life Sciences Education © 2015 The American Society for Cell Biology. This article is distributed by The American Society for Cell Biology under license from the author(s). It is available to the public under an Attribution–Noncommercial–Share Alike 3.0 Unported Creative Commons License (http://creativecommons.org/licenses/by-nc-sa/3.0).

  20. Sustaining Research Networks: the Twenty-Year Experience of the HMO Research Network.

    Science.gov (United States)

    Steiner, John F; Paolino, Andrea R; Thompson, Ella E; Larson, Eric B

    2014-01-01

    As multi-institutional research networks assume a central role in clinical research, they must address the challenge of sustainability. Despite its importance, the concept of network sustainability has received little attention in the literature, and the sustainability strategies of durable scientific networks have not been described. The Health Maintenance Organization Research Network (HMORN) is a consortium of 18 research departments in integrated health care delivery systems with over 15 million members in the United States and Israel. The HMORN has coordinated federally funded scientific networks and studies since 1994. This case study describes the HMORN approach to sustainability, proposes an operational definition of network sustainability, and identifies 10 essential elements that can enhance sustainability. The sustainability framework proposed here is drawn from prior publications on organizational issues by HMORN investigators and from the experience of recent HMORN leaders and senior staff. Network sustainability can be defined as (1) the development and enhancement of shared research assets to facilitate a sequence of research studies in a specific content area or multiple areas, and (2) a community of researchers and other stakeholders who reuse and develop those assets. Essential elements needed to develop the shared assets of a network include: network governance; trustworthy data and processes for sharing data; shared knowledge about research tools; administrative efficiency; physical infrastructure; and infrastructure funding. The community of researchers within a network is enhanced by: a clearly defined mission, vision and values; protection of human subjects; a culture of collaboration; and strong relationships with host organizations. While the importance of these elements varies based on the membership and goals of a network, this framework for sustainability can enhance strategic planning within the network and can guide relationships with

  1. Aversive Peer Experiences on Social Networking Sites: Development of the Social Networking-Peer Experiences Questionnaire (SN-PEQ).

    Science.gov (United States)

    Landoll, Ryan R; La Greca, Annette M; Lai, Betty S

    2013-12-01

    Cyber victimization is an important research area; yet, little is known about aversive peer experiences on social networking sites (SNSs), which are used extensively by youth and host complex social exchanges. Across samples of adolescents (n=216) and young adults (n=214), we developed the Social Networking-Peer Experiences Questionnaire (SN-PEQ), and examined its psychometric properties, distinctiveness from traditional peer victimization, and associations with internalized distress. The SN-PEQ demonstrated strong factorial invariance and a single factor structure that was distinct from other forms of peer victimization. Negative SNS experiences were associated with youths' symptoms of social anxiety and depression, even when controlling for traditional peer victimization. Findings highlight the importance of examining the effects of aversive peer experiences that occur via social media.

  2. Integrating Permafrost into an Earth System Model: First Sensitivity Experiments

    Science.gov (United States)

    Kitover, Danielle; Renssen, Hans; van Balen, Ronald; Vandenberghe, Jef

    2010-05-01

    Approximately one-fifth of the Northern Hemisphere's land surface is underlain by permafrost. Yet, to date, few global climate models have incorporated freeze/thaw soil processes and permafrost evolution into their simulations. This may be a significant component to omit since it has been well-established that like many parts of the Arctic system, permafrost is responding to a warming climate. As been observed at many sites around the circumpolar arctic, subarctic, and alpine locations, this includes warming soil temperatures, decreasing permafrost extent, and thickening active layer. Not only do freezing and thawing processes play a significant role in the land surface energy and moisture balance but such changes imply potential feedback effects as well. Specifically, changes in the permafrost regime can feedback to the climate system via three mechanisms: 1) as a source/sink of thermal energy through latent heat exchange, 2) as a regulator of regional hydrology, and 3) as a carbon reservoir. The best way to analyze these feedback effects, and hence the overall role of permafrost within the earth system, is to incorporate surface and subsurface freeze/thaw processes within a climate model. Therefore, as impetus to narrow this research gap, our project will be enhancing an existing earth system model of intermediate complexity called LOVECLIM by integrating a frozen soil algorithm within the land surface component. An examination of the permafrost-climate relationship will be done at both present climate and the last glacial maximum climate. We specifically focus at paleoclimate time scales that allow the simulations to capture the slow response time (relative to other earth system components) of permafrost and allow changes in permafrost and associated functions to feedback to the climate. However, before coupling to LOVECLIM, we first performed sensitivity experiments on the algorithm to determine the parameterization most fitting for the research scope. This

  3. Natural Cubic Spline Regression Modeling Followed by Dynamic Network Reconstruction for the Identification of Radiation-Sensitivity Gene Association Networks from Time-Course Transcriptome Data.

    Science.gov (United States)

    Michna, Agata; Braselmann, Herbert; Selmansberger, Martin; Dietz, Anne; Hess, Julia; Gomolka, Maria; Hornhardt, Sabine; Blüthgen, Nils; Zitzelsberger, Horst; Unger, Kristian

    2016-01-01

    Gene expression time-course experiments allow to study the dynamics of transcriptomic changes in cells exposed to different stimuli. However, most approaches for the reconstruction of gene association networks (GANs) do not propose prior-selection approaches tailored to time-course transcriptome data. Here, we present a workflow for the identification of GANs from time-course data using prior selection of genes differentially expressed over time identified by natural cubic spline regression modeling (NCSRM). The workflow comprises three major steps: 1) the identification of differentially expressed genes from time-course expression data by employing NCSRM, 2) the use of regularized dynamic partial correlation as implemented in GeneNet to infer GANs from differentially expressed genes and 3) the identification and functional characterization of the key nodes in the reconstructed networks. The approach was applied on a time-resolved transcriptome data set of radiation-perturbed cell culture models of non-tumor cells with normal and increased radiation sensitivity. NCSRM detected significantly more genes than another commonly used method for time-course transcriptome analysis (BETR). While most genes detected with BETR were also detected with NCSRM the false-detection rate of NCSRM was low (3%). The GANs reconstructed from genes detected with NCSRM showed a better overlap with the interactome network Reactome compared to GANs derived from BETR detected genes. After exposure to 1 Gy the normal sensitive cells showed only sparse response compared to cells with increased sensitivity, which exhibited a strong response mainly of genes related to the senescence pathway. After exposure to 10 Gy the response of the normal sensitive cells was mainly associated with senescence and that of cells with increased sensitivity with apoptosis. We discuss these results in a clinical context and underline the impact of senescence-associated pathways in acute radiation response of normal

  4. Mathematical inference and control of molecular networks from perturbation experiments

    Science.gov (United States)

    Mohammed-Rasheed, Mohammed

    One of the main challenges facing biologists and mathematicians in the post genomic era is to understand the behavior of molecular networks and harness this understanding into an educated intervention of the cell. The cell maintains its function via an elaborate network of interconnecting positive and negative feedback loops of genes, RNA and proteins that send different signals to a large number of pathways and molecules. These structures are referred to as genetic regulatory networks (GRNs) or molecular networks. GRNs can be viewed as dynamical systems with inherent properties and mechanisms, such as steady-state equilibriums and stability, that determine the behavior of the cell. The biological relevance of the mathematical concepts are important as they may predict the differentiation of a stem cell, the maintenance of a normal cell, the development of cancer and its aberrant behavior, and the design of drugs and response to therapy. Uncovering the underlying GRN structure from gene/protein expression data, e.g., microarrays or perturbation experiments, is called inference or reverse engineering of the molecular network. Because of the high cost and time consuming nature of biological experiments, the number of available measurements or experiments is very small compared to the number of molecules (genes, RNA and proteins). In addition, the observations are noisy, where the noise is due to the measurements imperfections as well as the inherent stochasticity of genetic expression levels. Intra-cellular activities and extra-cellular environmental attributes are also another source of variability. Thus, the inference of GRNs is, in general, an under-determined problem with a highly noisy set of observations. The ultimate goal of GRN inference and analysis is to be able to intervene within the network, in order to force it away from undesirable cellular states and into desirable ones. However, it remains a major challenge to design optimal intervention strategies

  5. Sensitivity analysis of a branching process evolving on a network with application in epidemiology

    CERN Document Server

    Hautphenne, Sophie; Delvenne, Jean-Charles; Blondel, Vincent D

    2015-01-01

    We perform an analytical sensitivity analysis for a model of a continuous-time branching process evolving on a fixed network. This allows us to determine the relative importance of the model parameters to the growth of the population on the network. We then apply our results to the early stages of an influenza-like epidemic spreading among a set of cities connected by air routes in the United States. We also consider vaccination and analyze the sensitivity of the total size of the epidemic with respect to the fraction of vaccinated people. Our analysis shows that the epidemic growth is more sensitive with respect to transmission rates within cities than travel rates between cities. More generally, we highlight the fact that branching processes offer a powerful stochastic modeling tool with analytical formulas for sensitivity which are easy to use in practice.

  6. Neural network models of learning and categorization in multigame experiments

    Directory of Open Access Journals (Sweden)

    Davide eMarchiori

    2011-12-01

    Full Text Available Previous research has shown that regret-driven neural networks predict behavior in repeated completely mixed games remarkably well, substantially equating the performance of the most accurate established models of learning. This result prompts the question of what is the added value of modeling learning through neural networks. We submit that this modeling approach allows for models that are able to distinguish among and respond differently to different payoff structures. Moreover, the process of categorization of a game is implicitly carried out by these models, thus without the need of any external explicit theory of similarity between games. To validate our claims, we designed and ran two multigame experiments in which subjects faced, in random sequence, different instances of two completely mixed 2x2 games. Then, we tested on our experimental data two regret-driven neural network models, and compared their performance with that of other established models of learning and Nash equilibrium.

  7. New accreditation program: university health network's experience with Qmentum.

    Science.gov (United States)

    Tepfers, Anita; Hruska, Christa; Stone, Justin; Moser, Jane

    2009-01-01

    In 2008, University Health Network was surveyed using Accreditation Canada's new Qmentum program. The following article describes UHN's experience rolling out the program to over 12,000 staff, physicians and volunteers. The article also outlines key challenges and lessons learned by the multi-site organization, with a focus on staff engagement, on-site survey preparation and sustainability moving forward. Staff feedback on the Qmentum program was extremely positive, and forecast results from Accreditation Canada were excellent.

  8. Coping with drought: the experience of water sensitive urban design ...

    African Journals Online (AJOL)

    This study investigated the extent of Water Sensitive Urban Design (WSUD) activities in the George Municipality in the Western Cape Province, South Africa, and its impact on water consumption. The WSUD approach aims to influence design and planning from the moment rainwater is captured in dams, to when it is treated, ...

  9. The Moderating Effect of Network Centrality on the Relationship Between Work Experience Variables and Organizational Commitment

    Science.gov (United States)

    2013-03-01

    network can be personal or social ( Ibarra & Andrews, 1993). While formal networks show the official rules and workings of an organization...THE MODERATING EFFECT OF NETWORK CENTRALITY ON THE RELATIONSHIP BETWEEN WORK EXPERIENCE VARIABLES...

  10. Humidity Sensitivity of Multi-Walled Carbon Nanotube Networks Deposited by Dielectrophoresis

    Directory of Open Access Journals (Sweden)

    Tianhong Cui

    2009-03-01

    Full Text Available This paper presents an investigation on the humidity sensitivity of deposited multi-walled carbon nanotube (MWCNT networks using ac dielectrophoresis (DEP between interdigitated electrodes (IDEs. MWCNTs dispersed in ethanol were trapped and enriched between IDEs on a Si/SiO2 substrate under a positive DEP force. After the DEP process, the ethanol was evaporated and the MWCNT network on a substrate with IDEs was put into a furnace for repeated thermal annealing. It was found that the resistance stability of the network was effectively improved through thermal annealing. The humidity sensitivity was obtained by measuring the resistance of the MWCNT network with different relative humidity at room temperature. The experimental results show the resistance increases linearly with increasing the relative humidity from 25% to 95% RH with a sensitivity of 0.5%/%RH. The MWCNT networks have a reversible humidity sensing capacity with response time and recovery time of about 3 s and 25 s, respectively. The resistance is dependent on temperature with a negative coefficient of about -0.33%/K in a temperature range from 293 K to 393 K.

  11. Design Optimization of Cyber-Physical Distributed Systems using IEEE Time-sensitive Networks (TSN)

    DEFF Research Database (Denmark)

    Pop, Paul; Lander Raagaard, Michael; Craciunas, Silviu S.

    2016-01-01

    In this paper we are interested in safety-critical real-time applications implemented on distributed architectures supporting the Time-SensitiveNetworking (TSN) standard. The ongoing standardization of TSN is an IEEE effort to bring deterministic real-time capabilities into the IEEE 802.1 Ethernet...

  12. Parametric sensitivity analysis for biochemical reaction networks based on pathwise information theory.

    Science.gov (United States)

    Pantazis, Yannis; Katsoulakis, Markos A; Vlachos, Dionisios G

    2013-10-22

    Stochastic modeling and simulation provide powerful predictive methods for the intrinsic understanding of fundamental mechanisms in complex biochemical networks. Typically, such mathematical models involve networks of coupled jump stochastic processes with a large number of parameters that need to be suitably calibrated against experimental data. In this direction, the parameter sensitivity analysis of reaction networks is an essential mathematical and computational tool, yielding information regarding the robustness and the identifiability of model parameters. However, existing sensitivity analysis approaches such as variants of the finite difference method can have an overwhelming computational cost in models with a high-dimensional parameter space. We develop a sensitivity analysis methodology suitable for complex stochastic reaction networks with a large number of parameters. The proposed approach is based on Information Theory methods and relies on the quantification of information loss due to parameter perturbations between time-series distributions. For this reason, we need to work on path-space, i.e., the set consisting of all stochastic trajectories, hence the proposed approach is referred to as "pathwise". The pathwise sensitivity analysis method is realized by employing the rigorously-derived Relative Entropy Rate, which is directly computable from the propensity functions. A key aspect of the method is that an associated pathwise Fisher Information Matrix (FIM) is defined, which in turn constitutes a gradient-free approach to quantifying parameter sensitivities. The structure of the FIM turns out to be block-diagonal, revealing hidden parameter dependencies and sensitivities in reaction networks. As a gradient-free method, the proposed sensitivity analysis provides a significant advantage when dealing with complex stochastic systems with a large number of parameters. In addition, the knowledge of the structure of the FIM can allow to efficiently address

  13. Experience with Delay-Tolerant Networking from Orbit

    Science.gov (United States)

    Ivancic, W.; Eddy, W. M.; Stewart, D.; Wood, L.; Northam, J.; Jackson, C.

    2010-01-01

    We describe the first use from space of the Bundle Protocol for Delay-Tolerant Networking (DTN) and lessons learned from experiments made and experience gained with this protocol. The Disaster Monitoring Constellation (DMC), constructed by Surrey Satellite Technology Ltd (SSTL), is a multiple-satellite Earth-imaging low-Earth-orbit sensor network in which recorded image swaths are stored onboard each satellite and later downloaded from the satellite payloads to a ground station. Store-and-forward of images with capture and later download gives each satellite the characteristics of a node in a disruption-tolerant network. Originally developed for the Interplanetary Internet, DTNs are now under investigation in an Internet Research Task Force (IRTF) DTN research group (RG), which has developed a bundle architecture and protocol. The DMC is technically advanced in its adoption of the Internet Protocol (IP) for its imaging payloads and for satellite command and control, based around reuse of commercial networking and link protocols. These satellites use of IP has enabled earlier experiments with the Cisco router in Low Earth Orbit (CLEO) onboard the constellation s UK-DMC satellite. Earth images are downloaded from the satellites using a custom IP-based high-speed transfer protocol developed by SSTL, Saratoga, which tolerates unusual link environments. Saratoga has been documented in the Internet Engineering Task Force (IETF) for wider adoption. We experiment with the use of DTNRG bundle concepts onboard the UK-DMC satellite, by examining how Saratoga can be used as a DTN convergence layer to carry the DTNRG Bundle Protocol, so that sensor images can be delivered to ground stations and beyond as bundles. Our practical experience with the first successful use of the DTNRG Bundle Protocol in a space environment gives us insights into the design of the Bundle Protocol and enables us to identify issues that must be addressed before wider deployment of the Bundle Protocol

  14. Sensitivity estimation for stochastic models of biochemical reaction networks in the presence of extrinsic variability

    Science.gov (United States)

    Ruess, Jakob; Koeppl, Heinz; Zechner, Christoph

    2017-03-01

    Determining the sensitivity of certain system states or outputs to variations in parameters facilitates our understanding of the inner working of that system and is an essential design tool for the de novo construction of robust systems. In cell biology, the output of interest is often the response of a certain reaction network to some input (e.g., stressors or nutrients) and one aims to quantify the sensitivity of this response in the presence of parameter heterogeneity. We argue that for such applications, parametric sensitivities in their standard form do not paint a complete picture of a system's robustness since one assumes that all cells in the population have the same parameters and are perturbed in the same way. Here, we consider stochastic reaction networks in which the parameters are randomly distributed over the population and propose a new sensitivity index that captures the robustness of system outputs upon changes in the characteristics of the parameter distribution, rather than the parameters themselves. Subsequently, we make use of Girsanov's likelihood ratio method to construct a Monte Carlo estimator of this sensitivity index. However, it turns out that this estimator has an exceedingly large variance. To overcome this problem, we propose a novel estimation algorithm that makes use of a marginalization of the path distribution of stochastic reaction networks and leads to Rao-Blackwellized estimators with reduced variance.

  15. Online social networking and the experience of cyber-bullying.

    Science.gov (United States)

    O'Dea, Bridianne; Campbell, Andrew

    2012-01-01

    Online social networking sites (SNS) are popular social tools used amongst adolescents and account for much of their daily internet activity. Recently, these sites have presented opportunities for youth to experience cyber-bullying. Often resulting in psychological distress, cyber-bullying is a common experience for many young people. Continual use of SNS signifies the importance of examining its links to cyber-bullying. This study examined the relationship between online social networking and the experience of cyber-bullying. A total of 400 participants (Mage=14.31 years) completed an online survey which examined the perceived definitions and frequency of cyber-bullying. Users of SNS reported significantly higher frequencies of stranger contact compared to non-users. Spearman's rho correlations determined no significant relationship between daily time on SNS and the frequency of stranger contact. This suggests that ownership of a SNS profile may be a stronger predictor of some cyber-bullying experiences compared to time spent on these sites. Findings encourage continued research on the nature of internet activities used by young adolescents and the possible exposure to online victimization.

  16. Identifying personal health experience tweets with deep neural networks.

    Science.gov (United States)

    Keyuan Jiang; Gupta, Ravish; Gupta, Matrika; Calix, Ricardo A; Bernard, Gordon R

    2017-07-01

    Twitter, as a social media platform, has become an increasingly useful data source for health surveillance studies, and personal health experiences shared on Twitter provide valuable information to the surveillance. Twitter data are known for their irregular usages of languages and informal short texts due to the 140 character limit, and for their noisiness such that majority of the posts are irrelevant to any particular health surveillance. These factors pose challenges in identifying personal health experience tweets from the Twitter data. In this study, we designed deep neural networks with 3 different architectural configurations, and after training them with a corpus of 8,770 annotated tweets, we used them to predict personal experience tweets from a set of 821 annotate tweets. Our results demonstrated a significant amount of improvement in predicting personal health experience tweets by deep neural networks over that by conventional classifiers: 37.5% in accuracy, 31.1% in precision, and 53.6% in recall. We believe that our method can be utilized in various health surveillance studies using Twitter as a data source.

  17. Disruption Tolerant Networking Flight Validation Experiment on NASA's EPOXI Mission

    Science.gov (United States)

    Wyatt, Jay; Burleigh, Scott; Jones, Ross; Torgerson, Leigh; Wissler, Steve

    2009-01-01

    In October and November of 2008, the Jet Propulsion Laboratory installed and tested essential elements of Delay/Disruption Tolerant Networking (DTN) technology on the Deep Impact spacecraft. This experiment, called Deep Impact Network Experiment (DINET), was performed in close cooperation with the EPOXI project which has responsibility for the spacecraft. During DINET some 300 images were transmitted from the JPL nodes to the spacecraft. Then they were automatically forwarded from the spacecraft back to the JPL nodes, exercising DTN's bundle origination, transmission, acquisition, dynamic route computation, congestion control, prioritization, custody transfer, and automatic retransmission procedures, both on the spacecraft and on the ground, over a period of 27 days. All transmitted bundles were successfully received, without corruption. The DINET experiment demonstrated DTN readiness for operational use in space missions. This activity was part of a larger NASA space DTN development program to mature DTN to flight readiness for a wide variety of mission types by the end of 2011. This paper describes the DTN protocols, the flight demo implementation, validation metrics which were created for the experiment, and validation results.

  18. The Journalism Studies Network (REJ experience: a French-language experiment in collaborative research

    Directory of Open Access Journals (Sweden)

    Zélia Leal Adghirni

    2011-12-01

    Full Text Available This article discusses the limitations and potentialities of journalism research utilizing the international networking model. It presents the experience of the Journalism Studies Network (REJ in the French/Portuguese acronym, a French-language research experiment, founded in 1999 and made up of 33 researchers linked to universities in Germany, Belgium, Brazil, Canada, France, Mexico and on Reunion Island. The report shows that despite the existing difficulties, the REJ takes the form of a place with relative autonomy in proposing objectives and methodologies for the study of journalism, which is reflected in the diversity of approaches and research interests developed within the Network. It also permits a more frank and level debate between researchers who occupy different positions in their careers. Coherence is also observed in the approaches adopted inside the REJ, which assures the continuity of the research programs developed.

  19. Teaching experience in university students using social networks

    Directory of Open Access Journals (Sweden)

    María del Rocío Carranza Alcántar

    2016-11-01

    Full Text Available Social networks, specifically Facebook and Twitter, are currently one of the mainstream media in the world, yet its educational use for the dissemination of knowledge is not significantly evident, under this premise this report is presented, considering an experience in which teachers and university-level students used these networks as mediators of educational practices; such mediation was implemented in order to promote mobile learning as an option to facilitate the process of construction and socialization of knowledge; In this sense, the research presented aimed to identify the experience and opinion of students regarding the influence of this strategy in achieving their learning. The quantitative methodology was applied through the application type of a survey of students who participated and realized the importance of socialization of knowledge. The results showed favorable opinions regarding the use of these networks, highlighting the benefits of mobile learning as a way to streamline the training process. The proposal is to continue this type of strategies to promote flexible teaching-learning options.

  20. HCIT Contrast Performance Sensitivity Studies: Simulation Versus Experiment

    Science.gov (United States)

    Sidick, Erkin; Shaklan, Stuart; Krist, John; Cady, Eric J.; Kern, Brian; Balasubramanian, Kunjithapatham

    2013-01-01

    Using NASA's High Contrast Imaging Testbed (HCIT) at the Jet Propulsion Laboratory, we have experimentally investigated the sensitivity of dark hole contrast in a Lyot coronagraph for the following factors: 1) Lateral and longitudinal translation of an occulting mask; 2) An opaque spot on the occulting mask; 3) Sizes of the controlled dark hole area. Also, we compared the measured results with simulations obtained using both MACOS (Modeling and Analysis for Controlled Optical Systems) and PROPER optical analysis programs with full three-dimensional near-field diffraction analysis to model HCIT's optical train and coronagraph.

  1. Deep Space Networking Experiments on the EPOXI Spacecraft

    Science.gov (United States)

    Jones, Ross M.

    2011-01-01

    NASA's Space Communications & Navigation Program within the Space Operations Directorate is operating a program to develop and deploy Disruption Tolerant Networking [DTN] technology for a wide variety of mission types by the end of 2011. DTN is an enabling element of the Interplanetary Internet where terrestrial networking protocols are generally unsuitable because they rely on timely and continuous end-to-end delivery of data and acknowledgments. In fall of 2008 and 2009 and 2011 the Jet Propulsion Laboratory installed and tested essential elements of DTN technology on the Deep Impact spacecraft. These experiments, called Deep Impact Network Experiment (DINET 1) were performed in close cooperation with the EPOXI project which has responsibility for the spacecraft. The DINET 1 software was installed on the backup software partition on the backup flight computer for DINET 1. For DINET 1, the spacecraft was at a distance of about 15 million miles (24 million kilometers) from Earth. During DINET 1 300 images were transmitted from the JPL nodes to the spacecraft. Then, they were automatically forwarded from the spacecraft back to the JPL nodes, exercising DTN's bundle origination, transmission, acquisition, dynamic route computation, congestion control, prioritization, custody transfer, and automatic retransmission procedures, both on the spacecraft and on the ground, over a period of 27 days. The first DINET 1 experiment successfully validated many of the essential elements of the DTN protocols. DINET 2 demonstrated: 1) additional DTN functionality, 2) automated certain tasks which were manually implemented in DINET 1 and 3) installed the ION SW on nodes outside of JPL. DINET 3 plans to: 1) upgrade the LTP convergence-layer adapter to conform to the international LTP CL specification, 2) add convergence-layer "stewardship" procedures and 3) add the BSP security elements [PIB & PCB]. This paper describes the planning and execution of the flight experiment and the

  2. Sensitive and robust electrophoretic NMR: Instrumentation and experiments

    Science.gov (United States)

    Hallberg, Fredrik; Furó, István; Yushmanov, Pavel V.; Stilbs, Peter

    2008-05-01

    Although simple as a concept, electrophoretic NMR (eNMR) has so far failed to find wider application. Problems encountered are mainly due to disturbing and partly irreproducible convection-like bulk flow effects from both electro-osmosis and thermal convection. Additionally, bubble formation at the electrodes and rf noise pickup has constrained the typical sample geometry to U-tube-like arrangements with a small filling factor and a low resulting NMR sensitivity. Furthermore, the sign of the electrophoretic mobility cancels out in U-tube geometries. We present here a new electrophoretic sample cell based on a vertically placed conventional NMR sample tube with bubble-suppressing palladium metal as electrode material. A suitable radiofrequency filter design prevents noise pickup by the NMR sample coil from the high-voltage leads which extend into the sensitive sample volume. Hence, the obtained signal-to-noise ratio of this cell is one order of magnitude higher than that of our previous U-tube cells. Permitted by the retention of the sign of the displacement-related signal phase in the new cell design, an experimental approach is described where bulk flow effects by electro-osmosis and/or thermal convection are compensated through parallel monitoring of a reference signal from a non-charged species in the sample. This approach, together with a CPMG-like pulse train scheme provides a superior first-order cancellation of non-electrophoretic bulk flow effects.

  3. Effects of Port Congestion in the Gate Control List Scheduling of Time Sensitive Networks

    DEFF Research Database (Denmark)

    Kentis, Angelos Mimidis; Berger, Michael Stübert; Soler, José

    2017-01-01

    is directly related with the delay; hence reducing it can be beneficial within the TSN paradigm. This paper investigates the effects of port congestion, in the duration of the network wide schedule. A congested port can make scheduling more complex, leading to longer network-wide schedules. To verify this......, the same set of experiments was repeated, with and without considering port congestion during path allocation. The computed paths were given as input to an implementation of the shifting bottleneck heuristic algorithm. The shifting bottleneck heuristic, computed the network-wide gating schedule...

  4. Networked Memory Project: A Policy Thought Experiment for the Archiving of Social Networks by the Library of Congress of the United States

    Directory of Open Access Journals (Sweden)

    Chloé S. Georas

    2014-07-01

    Full Text Available This article explores the challenges posed by an archival interest in the broad palimpsest of daily life left on social networks that are controlled by private corporations. It addresses whether social networks should be archived for the benefit of future generations and proposes a policy thought experiment to help grapple with these questions, namely, the proposal for the formation of the public interest-oriented Networked Memory Project by the Library of Congress for the archiving of social networks. My discussion of the challenges posed by this thought experiment will focus on the U.S. legal framework within which the Library of Congress operates and take Facebook. To the extent that social networks have user-generated contents that range from the highly “private” to “public” as opposed to other networked platforms that contain materials that are considered “public”, the bar for the historical archival of social networks is much higher. Almost every archival effort must contend with the legal hurdle of copyright, but the archiving of social networks must also address how to handle the potentially sensitive nature of materials that are considered “private” from the perspective of the social and legal constructions of privacy. My theoretical exercise of proposing the formation of the Networked Memory Project by the Library of Congress responds to the need to consider the benefits of a public interest-oriented archive of social networks that can counter the drawbacks of the incidental corporate archiving taking place on social networks.

  5. EPILEPSY A SOCIAL APPROACH: EXPERIENCE OF SENSITIZATION AND AWARENESS PUBLIC

    Directory of Open Access Journals (Sweden)

    Ivana Valeria Reyes Hernández

    2016-12-01

    Full Text Available Epilepsy as neurological disease affects the person who suffers from it by the deteriorating level of physical, mental, and personnel that results. It is a disease with various forms of manifestation, condition, and can occur at any age, regardless of race, social status, educational level. Condition is not well documented, by which communities have doubts, concerns, sometimes it becomes a social stigma, and it is unknown that is a controllable disease and that deterioration may decrease in the quality of life of the patient. This dissertation will present an approach of sensitization citizen in Venezuela to way of contributing with a perspective social on the disease. The methodology is of type documentary, bibliographic, field, and cross type. Applied an instrument in the visited social and communal spaces, their responses were reviewed at the same meeting and applied proactively public awareness program.

  6. Mimicking directed binary networks for exploring systemic sensitivity: Is NCAA FBS a fragile competition system?

    Directory of Open Access Journals (Sweden)

    Fushing Hsieh

    2016-07-01

    Full Text Available Can a popular real-world competition system indeed be fragile? To address this question, we represent such a system by a directed binary network. Upon observed network data, typically in a form of win-and-loss matrix, our computational developments begin with collectively extracting network's information flows. And then we compute and discover network's macrostate. This computable macrostate is further shown to contain deterministic structures embedded with randomness mechanisms. Such coupled deterministic and stochastic components becomes the basis for generating the microstate ensemble. Specifically a network mimicking algorithm is proposed to generate a microstate ensemble by subject to the statistical mechanics principle: All generated microscopic states have to conform to its macrostate of the target system. We demonstrate that such a microstate ensemble is an effective platform for exploring systemic sensitivity. Throughout our computational developments, we employ the NCAA Football Bowl Subdivision (FBS as an illustrating example system. Upon this system, its macrostate is discovered by having a nonlinear global ranking hierarchy as its deterministic component, while its constrained randomness component is embraced within the nearly completely recovered conference schedule . Based on the computed microstate ensemble, we are able to conclude that the NCAA FBS is overall a fragile competition system because it retains highly heterogeneous degrees of sensitivity with its ranking hierarchy.

  7. Sensitivity of the active fracture model parameter to fracture network orientation and injection scenarios

    Science.gov (United States)

    Başağaoğlu, Hakan; Succi, Sauro; Manepally, Chandrika; Fedors, Randall; Wyrick, Danielle Y.

    2009-09-01

    Active fractures refer to the portions of unsaturated, connected fractures that actively conduct water. The active fracture model parameter accounts for the reduction in the number of fractures carrying water and in the fracture-matrix interface area in field-scale simulations of flow and transport in unsaturated fractured rocks. One example includes the numerical analyses of the fault test results at the Yucca Mountain site, Nevada (USA). In such applications, the active fracture model parameter is commonly used as a calibration parameter without relating it to fracture network orientations and infiltration rates. A two-dimensional, multiphase lattice-Boltzmann model was used in this study to investigate the sensitivity of the active fracture model parameter to fracture network orientation and injection scenarios for an unsaturated, variable dipping, and geometrically simple fracture network. The active fracture model parameter differed by as much as 0.11-0.44 when the effects of fracture network orientation, injection rate, and injection mode were included in the simulations. Hence, the numerical results suggest that the sensitivity of the active fracture model parameter to fracture network orientation, injection rates, and injection modes should be explored at the field-scale to strengthen the technical basis and range of applicability of the active fracture model.

  8. Comprehensive mechanisms for combustion chemistry: Experiment, modeling, and sensitivity analysis

    Energy Technology Data Exchange (ETDEWEB)

    Dryer, F.L.; Yetter, R.A. [Princeton Univ., NJ (United States)

    1993-12-01

    This research program is an integrated experimental/numerical effort to study pyrolysis and oxidation reactions and mechanisms for small-molecule hydrocarbon structures under conditions representative of combustion environments. The experimental aspects of the work are conducted in large diameter flow reactors, at pressures from one to twenty atmospheres, temperatures from 550 K to 1200 K, and with observed reaction times from 10{sup {minus}2} to 5 seconds. Gas sampling of stable reactant, intermediate, and product species concentrations provides not only substantial definition of the phenomenology of reaction mechanisms, but a significantly constrained set of kinetic information with negligible diffusive coupling. Analytical techniques used for detecting hydrocarbons and carbon oxides include gas chromatography (GC), and gas infrared (NDIR) and FTIR methods are utilized for continuous on-line sample detection of light absorption measurements of OH have also been performed in an atmospheric pressure flow reactor (APFR), and a variable pressure flow (VPFR) reactor is presently being instrumented to perform optical measurements of radicals and highly reactive molecular intermediates. The numerical aspects of the work utilize zero and one-dimensional pre-mixed, detailed kinetic studies, including path, elemental gradient sensitivity, and feature sensitivity analyses. The program emphasizes the use of hierarchical mechanistic construction to understand and develop detailed kinetic mechanisms. Numerical studies are utilized for guiding experimental parameter selections, for interpreting observations, for extending the predictive range of mechanism constructs, and to study the effects of diffusive transport coupling on reaction behavior in flames. Modeling using well defined and validated mechanisms for the CO/H{sub 2}/oxidant systems.

  9. Network Performance and Quality of Experience of Remote Access Laboratories

    Directory of Open Access Journals (Sweden)

    Alexander A. Kist

    2012-11-01

    Full Text Available Remote Access Laboratories (RAL have become important learning and teaching tools. This paper presents a performance study that targets a specific remote access architecture implemented within a universities operational environment. This particular RAL system provides globally authenticated and arbitrated remote access to virtualized computers as well as computer controlled hardware experiments. This paper presents system performance results that have been obtained utilizing both a set of automated and human subject tests. Principle objectives of the study were: To gain a better understanding of the nature of network traffic caused by experimental activity usage; to obtain an indication of user expectations of activity performance; and to develop a measure to predict Quality of Experience, based on easily measurable Quality of Service parameters. The study emulates network layer variation of access-bandwidth and round-trip-time of typical usage scenarios and contrasts against user perception results that allow classifying expected user performance. It demonstrates that failure rate is excellent measure of usability, and that round-trip-time predominantly affects user experience. Thin-client and remote desktop architectures are popular to separate the location of users and the actual data processing and use similar structures, hence results of this study to be applied in these application areas as well.

  10. New results from ADMX -- an ultra sensitive axion detection experiment

    Science.gov (United States)

    Asztalos, Steven J.

    2009-11-01

    Axions are hypothetical pseudoscalar particles that exist as a consequence of the Peccei-Quinn solution to the strong-CP problem. Light axions (ueV-meV) are also a natural cold dark matter candidate. One important detection technique is via resonant conversion to microwave photons in a high-Q cavity immersed in a strong magnetic field. In this class of experiment, the signal from the cavity is amplified by an ultralow noise amplifier, and mixed down to the audio frequency range using a double-heterodyne receiver. The power spectrum results by a Fast Fourier Transform, with the putative axion appearing as a narrow line at a frequency corresponding to its rest mass. This detection strategy provides the basis for the Axion Dark Matter eXperiment (ADMX) which has been taking data at Lawrence Livermore National Laboratory (LLNL) since 1996. ADMX has established limits in two distinct data channels - a medium resolution channel configured to search for ``thermalized'' axions and a high resolution channel for detecting axions that have recently fallen into the gravitational well of our galaxy. This talk will present an overview of the newly reconfigured experiment featuring an ultralow-noise first stage cryogenic SQUID amplifiers and present latest results from the two data channels.

  11. Simultaneous stability and sensitivity in model cortical networks is achieved through anti-correlations between the in- and out-degree of connectivity

    Directory of Open Access Journals (Sweden)

    Juan Carlos Vasquez

    2013-11-01

    Full Text Available Neuronal networks in rodent barrel cortex are characterized by stable low baseline firing rates. However, they are sensitive to the action potentials of single neurons as suggested by recent single-cell stimulation experiments that report quantifiable behavioral responses in response to short spike trains elicited in single neurons. Hence, these networks are stable against internally generated fluctuations in firing rate but at the same time remain sensitive to similarly-sized externally induced perturbations. We investigated stability and sensitivity in a simple recurrent network of stochastic binary neurons and determined numerically the effects of correlation between the number of afferent (‘in-degree’ and efferent (‘out-degree’ connections in neurons. The key advance reported in this work is that anti-correlation between in-/out-degree distributions increased the stability of the network in comparison to networks with no correlation or positive correlations, while being able to achieve the same level of sensitivity. The experimental characterization of degree distributions is difficult because all presynaptic and postsynaptic neurons have to be identified and counted. We explored whether the statistics of network motifs, which requires the characterization of connections between small subsets of neurons, could be used to detect evidence for degree anti-correlations. We find that the sample frequency of the 3-neuron ‘ring’ motif (1→2→3→1, can be used to detect degree anti-correlation for sub-networks of size 30 using about 50 samples, which is of significance because the necessary measurements are achievable experimentally in the near future.Taken together, we hypothesize that barrel cortex networks exhibit degree anti-correlations and specific network motif statistics.

  12. Use of collateral sensitivity networks to design drug cycling protocols that avoid resistance development

    DEFF Research Database (Denmark)

    Imamovic, Lejla; Sommer, Morten

    2013-01-01

    and select against drug resistance development. We identified hundreds of such drug sets and demonstrated that the antibiotics gentamicin and cefuroxime can be deployed cyclically such that the treatment regimen selected against resistance to either drug. We then validated our findings with related bacterial......New drug deployment strategies are imperative to address the problem of drug resistance, which is limiting the management of infectious diseases and cancers. We evolved resistance in Escherichia coli toward 23 drugs used clinically for treating bacterial infections and mapped the resulting...... collateral sensitivity and resistance profiles, revealing a complex collateral sensitivity network. On the basis of these data, we propose a new treatment framework-collateral sensitivity cycling-in which drugs with compatible collateral sensitivity profiles are used sequentially to treat infection...

  13. Risk Assessment of Distribution Network Based on Random set Theory and Sensitivity Analysis

    Science.gov (United States)

    Zhang, Sh; Bai, C. X.; Liang, J.; Jiao, L.; Hou, Z.; Liu, B. Zh

    2017-05-01

    Considering the complexity and uncertainty of operating information in distribution network, this paper introduces the use of random set for risk assessment. The proposed method is based on the operating conditions defined in the random set framework to obtain the upper and lower cumulative probability functions of risk indices. Moreover, the sensitivity of risk indices can effectually reflect information about system reliability and operating conditions, and by use of these information the bottlenecks that suppress system reliability can be found. The analysis about a typical radial distribution network shows that the proposed method is reasonable and effective.

  14. Degree Correlations Optimize Neuronal Network Sensitivity to Sub-Threshold Stimuli.

    Science.gov (United States)

    Schmeltzer, Christian; Kihara, Alexandre Hiroaki; Sokolov, Igor Michailovitsch; Rüdiger, Sten

    2015-01-01

    Information processing in the brain crucially depends on the topology of the neuronal connections. We investigate how the topology influences the response of a population of leaky integrate-and-fire neurons to a stimulus. We devise a method to calculate firing rates from a self-consistent system of equations taking into account the degree distribution and degree correlations in the network. We show that assortative degree correlations strongly improve the sensitivity for weak stimuli and propose that such networks possess an advantage in signal processing. We moreover find that there exists an optimum in assortativity at an intermediate level leading to a maximum in input/output mutual information.

  15. Analysis of sensor network observations during some simulated landslide experiments

    Science.gov (United States)

    Scaioni, M.; Lu, P.; Feng, T.; Chen, W.; Wu, H.; Qiao, G.; Liu, C.; Tong, X.; Li, R.

    2012-12-01

    A multi-sensor network was tested during some experiments on a landslide simulation platform established at Tongji University (Shanghai, P.R. China). Here landslides were triggered by means of artificial rainfall (see Figure 1). The sensor network currently incorporates contact sensors and two imaging systems. This represent a novel solution, because the spatial sensor network incorporate either contact sensors and remote sensors (video-cameras). In future, these sensors will be installed on two real ground slopes in Sichuan province (South-West China), where Wenchuan earthquake occurred in 2008. This earthquake caused the immediate activation of several landslide, while other area became unstable and still are a menace for people and properties. The platform incorporates the reconstructed scale slope, sensor network, communication system, database and visualization system. Some landslide simulation experiments allowed ascertaining which sensors could be more suitable to be deployed in Wenchuan area. The poster will focus on the analysis of results coming from down scale simulations. Here the different steps of the landslide evolution can be followed on the basis of sensor observations. This include underground sensors to detect the water table level and the pressure in the ground, a set of accelerometers and two inclinometers. In the first part of the analysis the full data series are investigated to look for correlations and common patterns, as well as to link them to the physical processes. In the second, 4 subsets of sensors located in neighbor positions are analyzed. The analysis of low- and high-speed image sequences allowed to track a dense field of displacement on the slope surface. These outcomes have been compared to the ones obtained from accelerometers for cross-validation. Images were also used for the photogrammetric reconstruction of the slope topography during the experiment. Consequently, volume computation and mass movements could be evaluated on

  16. Ambiguity in Social Network Data for Presence, Sensitive-Attribute, Degree and Relationship Privacy Protection.

    Science.gov (United States)

    Rajaei, Mehri; Haghjoo, Mostafa S; Miyaneh, Eynollah Khanjari

    2015-01-01

    Maintaining privacy in network data publishing is a major challenge. This is because known characteristics of individuals can be used to extract new information about them. Recently, researchers have developed privacy methods based on k-anonymity and l-diversity to prevent re-identification or sensitive label disclosure through certain structural information. However, most of these studies have considered only structural information and have been developed for undirected networks. Furthermore, most existing approaches rely on generalization and node clustering so may entail significant information loss as all properties of all members of each group are generalized to the same value. In this paper, we introduce a framework for protecting sensitive attribute, degree (the number of connected entities), and relationships, as well as the presence of individuals in directed social network data whose nodes contain attributes. First, we define a privacy model that specifies privacy requirements for the above private information. Then, we introduce the technique of Ambiguity in Social Network data (ASN) based on anatomy, which specifies how to publish social network data. To employ ASN, individuals are partitioned into groups. Then, ASN publishes exact values of properties of individuals of each group with common group ID in several tables. The lossy join of those tables based on group ID injects uncertainty to reconstruct the original network. We also show how to measure different privacy requirements in ASN. Simulation results on real and synthetic datasets demonstrate that our framework, which protects from four types of private information disclosure, preserves data utility in tabular, topological and spectrum aspects of networks at a satisfactory level.

  17. Ambiguity in Social Network Data for Presence, Sensitive-Attribute, Degree and Relationship Privacy Protection.

    Directory of Open Access Journals (Sweden)

    Mehri Rajaei

    Full Text Available Maintaining privacy in network data publishing is a major challenge. This is because known characteristics of individuals can be used to extract new information about them. Recently, researchers have developed privacy methods based on k-anonymity and l-diversity to prevent re-identification or sensitive label disclosure through certain structural information. However, most of these studies have considered only structural information and have been developed for undirected networks. Furthermore, most existing approaches rely on generalization and node clustering so may entail significant information loss as all properties of all members of each group are generalized to the same value. In this paper, we introduce a framework for protecting sensitive attribute, degree (the number of connected entities, and relationships, as well as the presence of individuals in directed social network data whose nodes contain attributes. First, we define a privacy model that specifies privacy requirements for the above private information. Then, we introduce the technique of Ambiguity in Social Network data (ASN based on anatomy, which specifies how to publish social network data. To employ ASN, individuals are partitioned into groups. Then, ASN publishes exact values of properties of individuals of each group with common group ID in several tables. The lossy join of those tables based on group ID injects uncertainty to reconstruct the original network. We also show how to measure different privacy requirements in ASN. Simulation results on real and synthetic datasets demonstrate that our framework, which protects from four types of private information disclosure, preserves data utility in tabular, topological and spectrum aspects of networks at a satisfactory level.

  18. SPSens: a software package for stochastic parameter sensitivity analysis of biochemical reaction networks.

    Science.gov (United States)

    Sheppard, Patrick W; Rathinam, Muruhan; Khammash, Mustafa

    2013-01-01

    SPSens is a software package for the efficient computation of stochastic parameter sensitivities of biochemical reaction networks. Parameter sensitivity analysis is a valuable tool that can be used to study robustness properties, for drug targeting, and many other purposes. However its application to stochastic models has been limited when Monte Carlo methods are required due to extremely high computational costs. SPSens provides efficient, state of the art sensitivity analysis algorithms in a single software package so that sensitivity analysis can be easily performed on stochastic models of biochemical reaction networks. SPSens implements the algorithms in C and estimates sensitivities with respect to both infinitesimal and finite perturbations to system parameters, in many cases reducing variance by orders of magnitude compared to basic methods. Included among the features of SPSens are serial and parallel command line versions, an interface with Matlab, and several example problems. SPSens is distributed freely under GPL version 3 and can be downloaded from http://sourceforge.net/projects/spsens/. The software can be run on Linux, Mac OS X and Windows platforms.

  19. Utilizing HPC Network Technologies in High Energy Physics Experiments

    CERN Document Server

    AUTHOR|(CDS)2088631; The ATLAS collaboration

    2017-01-01

    Because of their performance characteristics high-performance fabrics like Infiniband or OmniPath are interesting technologies for many local area network applications, including data acquisition systems for high-energy physics experiments like the ATLAS experiment at CERN. This paper analyzes existing APIs for high-performance fabrics and evaluates their suitability for data acquisition systems in terms of performance and domain applicability. The study finds that existing software APIs for high-performance interconnects are focused on applications in high-performance computing with specific workloads and are not compatible with the requirements of data acquisition systems. To evaluate the use of high-performance interconnects in data acquisition systems a custom library, NetIO, is presented and compared against existing technologies. NetIO has a message queue-like interface which matches the ATLAS use case better than traditional HPC APIs like MPI. The architecture of NetIO is based on a interchangeable bac...

  20. Wireless Power Transfer Protocols in Sensor Networks: Experiments and Simulations

    Directory of Open Access Journals (Sweden)

    Sotiris Nikoletseas

    2017-04-01

    Full Text Available Rapid technological advances in the domain of Wireless Power Transfer pave the way for novel methods for power management in systems of wireless devices, and recent research works have already started considering algorithmic solutions for tackling emerging problems. In this paper, we investigate the problem of efficient and balanced Wireless Power Transfer in Wireless Sensor Networks. We employ wireless chargers that replenish the energy of network nodes. We propose two protocols that configure the activity of the chargers. One protocol performs wireless charging focused on the charging efficiency, while the other aims at proper balance of the chargers’ residual energy. We conduct detailed experiments using real devices and we validate the experimental results via larger scale simulations. We observe that, in both the experimental evaluation and the evaluation through detailed simulations, both protocols achieve their main goals. The Charging Oriented protocol achieves good charging efficiency throughout the experiment, while the Energy Balancing protocol achieves a uniform distribution of energy within the chargers.

  1. Highly sensitive integrated pressure sensor with horizontally oriented carbon nanotube network.

    Science.gov (United States)

    Mohammad Haniff, Muhammad Aniq Shazni; Lee, Hing Wah; Bien, Daniel Chia Sheng; Teh, Aun Shih; Azid, Ishak Abdul

    2014-01-28

    This paper presents a functionalized, horizontally oriented carbon nanotube network as a sensing element to enhance the sensitivity of a pressure sensor. The synthesis of horizontally oriented nanotubes from the AuFe catalyst and their deposition onto a mechanically flexible substrate via transfer printing are studied. Nanotube formation on thermally oxidized Si (100) substrates via plasma-enhanced chemical vapor deposition controls the nanotube coverage and orientation on the flexible substrate. These nanotubes can be simply transferred to the flexible substrate without changing their physical structure. When tested under a pressure range of 0 to 50 kPa, the performance of the fabricated pressure sensor reaches as high as approximately 1.68%/kPa, which indicates high sensitivity to a small change of pressure. Such sensitivity may be induced by the slight contact in isolated nanotubes. This nanotube formation, in turn, enhances the modification of the contact and tunneling distance of the nanotubes upon the deformation of the network. Therefore, the horizontally oriented carbon nanotube network has great potential as a sensing element for future transparent sensors.

  2. Highly sensitive lactate biosensor by engineering chitosan/PVI-Os/CNT/LOD network nanocomposite.

    Science.gov (United States)

    Cui, Xiaoqiang; Li, Chang Ming; Zang, Jianfeng; Yu, Shucong

    2007-06-15

    A novel chitosan/PVI-Os(polyvinylimidazole-Os)/CNT(carbon nanotube)/LOD (lactate oxidase) network nanocomposite was constructed on gold electrode for detection of lactate. The composite was nanoengineered by selected matched material components and optimized composition ratio to produce a superior lactate sensor. Positively charged chitosan and PVI-Os were used as the matrix and the mediator to immobilize the negatively charged LOD and to enhance the electron transfer, respectively. CNTs were introduced as the essential component in the composite for the network nanostructure. FESEM (field emission scan electron microscopy) and electrochemical characterization demonstrated that CNT behaved as a cross-linker to network PVI and chitosan due to its nanoscaled and negative charged nature. This significantly improved the conductivity, stability and electroactivity for detection of lactate. The standard deviation of the sensor without CNT in the composite was greatly reduced from 19.6 to 4.9% by addition of CNTs. With optimized conditions the sensitivity and detection limit of the lactate sensor was 19.7 microA mM(-1)cm(-2) and 5 microM, respectively. The sensitivity was remarkably improved in comparison to the newly reported values of 0.15-3.85 microA mM(-1)cm(-2). This novel nanoengineering approach for selecting matched components to form a network nanostructure could be extended to other enzyme biosensors, and to have broad potential applications in diagnostics, life science and food analysis.

  3. Sensitivity Study of Optimal eICIC Configurations in Different Heterogeneous Network Scenarios

    DEFF Research Database (Denmark)

    Wang, Yuanye; Alvarez, Beatriz Soret; Pedersen, Klaus I.

    2012-01-01

    Heterogeneous Networks (HetNet) have been recognized as a key enabler for providing high data rates. However, co-channel deployed HetNet will experience inter-layer interference, and hence calls for use of enhanced Inter-Cell Interference Coordination (eICIC) to solve such interference problems...

  4. Snow and ice on Bear Lake (Alaska – sensitivity experiments with two lake ice models

    Directory of Open Access Journals (Sweden)

    Tido Semmler

    2012-03-01

    Full Text Available Snow and ice thermodynamics of Bear Lake (Alaska are investigated with a simple freshwater lake model (FLake and a more complex snow and ice thermodynamic model (HIGHTSI. A number of sensitivity experiments have been carried out to investigate the influence of snow and ice parameters and of different complexity on the results. Simulation results are compared with observations from the Alaska Lake Ice and Snow Observatory Network. Adaptations of snow thermal and optical properties in FLake can largely improve accuracy of the results. Snow-to-ice transformation is important for HIGHTSI to calculate the total ice mass balance. The seasonal maximum ice depth is simulated in FLake with a bias of −0.04 m and in HIGHTSI with no bias. Correlation coefficients between ice depth measurements and simulations are high (0.74 for FLake and 0.9 for HIGHTSI. The snow depth simulation can be improved by taking into account a variable snow density. Correlation coefficients for surface temperature are 0.72 for FLake and 0.81 for HIGHTSI. Overall, HIGHTSI gives slightly more accurate surface temperature than FLake probably due to the consideration of multiple snow and ice layers and the expensive iteration calculation procedure.

  5. Sensitivity experiments with an adaptation model of circulation of western tropical Indian Ocean

    Digital Repository Service at National Institute of Oceanography (India)

    Bahulayan, N.; Shaji, C.; Rao, A.D.; Dube, S.K.

    One 18-level adaptation model of circulation with a flat bottom at 900 m depth has been used to study the sensitivity of the solution to different magnitudes of eddy viscosity and diffusivity coefficients. Three numerical experiments conducted...

  6. An overview of the design and analysis of simulation experiments for sensitivity analysis

    NARCIS (Netherlands)

    Kleijnen, J.P.C.

    2005-01-01

    Sensitivity analysis may serve validation, optimization, and risk analysis of simulation models. This review surveys 'classic' and 'modern' designs for experiments with simulation models. Classic designs were developed for real, non-simulated systems in agriculture, engineering, etc. These designs

  7. Efficient Simulation of Wing Modal Response: Application of 2nd Order Shape Sensitivities and Neural Networks

    Science.gov (United States)

    Kapania, Rakesh K.; Liu, Youhua

    2000-01-01

    At the preliminary design stage of a wing structure, an efficient simulation, one needing little computation but yielding adequately accurate results for various response quantities, is essential in the search of optimal design in a vast design space. In the present paper, methods of using sensitivities up to 2nd order, and direct application of neural networks are explored. The example problem is how to decide the natural frequencies of a wing given the shape variables of the structure. It is shown that when sensitivities cannot be obtained analytically, the finite difference approach is usually more reliable than a semi-analytical approach provided an appropriate step size is used. The use of second order sensitivities is proved of being able to yield much better results than the case where only the first order sensitivities are used. When neural networks are trained to relate the wing natural frequencies to the shape variables, a negligible computation effort is needed to accurately determine the natural frequencies of a new design.

  8. High Sensitivity Gas Detection Using a Macroscopic Three-Dimensional Graphene Foam Network

    Science.gov (United States)

    Yavari, Fazel; Chen, Zongping; Thomas, Abhay V.; Ren, Wencai; Cheng, Hui-Ming; Koratkar, Nikhil

    2011-11-01

    Nanostructures are known to be exquisitely sensitive to the chemical environment and offer ultra-high sensitivity for gas-sensing. However, the fabrication and operation of devices that use individual nanostructures for sensing is complex, expensive and suffers from poor reliability due to contamination and large variability from sample-to-sample. By contrast, conventional solid-state and conducting-polymer sensors offer excellent reliability but suffer from reduced sensitivity at room-temperature. Here we report a macro graphene foam-like three-dimensional network which combines the best of both worlds. The walls of the foam are comprised of few-layer graphene sheets resulting in high sensitivity; we demonstrate parts-per-million level detection of NH3 and NO2 in air at room-temperature. Further, the foam is a mechanically robust and flexible macro-scale network that is easy to contact (without Lithography) and can rival the durability and affordability of traditional sensors. Moreover, Joule-heating expels chemisorbed molecules from the foam's surface leading to fully-reversible and low-power operation.

  9. How the government's punishment and individual's sensitivity affect the rumor spreading in online social networks

    Science.gov (United States)

    Li, Dandan; Ma, Jing

    2017-03-01

    We explore the impact of punishment of governments and sensitivity of individuals on the rumor spreading in this paper. Considering the facts that some rumors that relate to the hot events could be disseminated repeatedly, however, some other rumors will never be disseminated after they have been popular for some time. Therefore, we investigate two types (SIS and SIR) of rumor spreading models in which the punishment of government and sensitivity of individuals are considered. Based on the mean-field method, we have calculated the spreading threshold of SIS and SIR model, respectively. Furthermore, we perform the rumor spreading process in the Facebook and POK social networks, and achieve that there is an excellent agreement between the theoretical and numerical results of spreading threshold. The results indicate that improving the punishment of government and increasing the sensitivity of individuals could control the spreading of rumor effectively.

  10. Parallel replica dynamics method for bistable stochastic reaction networks: Simulation and sensitivity analysis

    Science.gov (United States)

    Wang, Ting; Plecháč, Petr

    2017-12-01

    Stochastic reaction networks that exhibit bistable behavior are common in systems biology, materials science, and catalysis. Sampling of stationary distributions is crucial for understanding and characterizing the long-time dynamics of bistable stochastic dynamical systems. However, simulations are often hindered by the insufficient sampling of rare transitions between the two metastable regions. In this paper, we apply the parallel replica method for a continuous time Markov chain in order to improve sampling of the stationary distribution in bistable stochastic reaction networks. The proposed method uses parallel computing to accelerate the sampling of rare transitions. Furthermore, it can be combined with the path-space information bounds for parametric sensitivity analysis. With the proposed methodology, we study three bistable biological networks: the Schlögl model, the genetic switch network, and the enzymatic futile cycle network. We demonstrate the algorithmic speedup achieved in these numerical benchmarks. More significant acceleration is expected when multi-core or graphics processing unit computer architectures and programming tools such as CUDA are employed.

  11. Enhancement of signal sensitivity in a heterogeneous neural network refined from synaptic plasticity

    Energy Technology Data Exchange (ETDEWEB)

    Li Xiumin; Small, Michael, E-mail: ensmall@polyu.edu.h, E-mail: 07901216r@eie.polyu.edu.h [Department of Electronic and Information Engineering, Hong Kong Polytechnic University, Hung Hom, Kowloon (Hong Kong)

    2010-08-15

    Long-term synaptic plasticity induced by neural activity is of great importance in informing the formation of neural connectivity and the development of the nervous system. It is reasonable to consider self-organized neural networks instead of prior imposition of a specific topology. In this paper, we propose a novel network evolved from two stages of the learning process, which are respectively guided by two experimentally observed synaptic plasticity rules, i.e. the spike-timing-dependent plasticity (STDP) mechanism and the burst-timing-dependent plasticity (BTDP) mechanism. Due to the existence of heterogeneity in neurons that exhibit different degrees of excitability, a two-level hierarchical structure is obtained after the synaptic refinement. This self-organized network shows higher sensitivity to afferent current injection compared with alternative archetypal networks with different neural connectivity. Statistical analysis also demonstrates that it has the small-world properties of small shortest path length and high clustering coefficients. Thus the selectively refined connectivity enhances the ability of neuronal communications and improves the efficiency of signal transmission in the network.

  12. Student nurses' experiences of living and studying in a different culture to their own and the development of cultural sensitivity

    DEFF Research Database (Denmark)

    Ruddock, Heidi

    characteristics of openness and flexibility and support networks facilitated the students transition and adjustment to the host culture. Reflection on their experiences with students from a similar background to themselves and clinical mentors from the host culture assisted the students in their understanding......With the increase of culturally diverse people residing in Denmark, it has become imperative to provide student nurses with knowledge and skills that will enable them to become culturally sensitive in order interact effectively with clients from culturally diverse backgrounds. The aim of this study...... was to explore whether student nurses develop cultural sensitivity as a consequence of living and studying in a culture that is different from their own. Seven Danish student nurses who had participated in student exchanges in Jamaica, Australia, Malta and Greenland took part in this study. A qualitative...

  13. Context-sensitive network-based disease genetics prediction and its implications in drug discovery.

    Science.gov (United States)

    Chen, Yang; Xu, Rong

    2017-04-01

    Disease phenotype networks play an important role in computational approaches to identifying new disease-gene associations. Current disease phenotype networks often model disease relationships based on pairwise similarities, therefore ignore the specific context on how two diseases are connected. In this study, we propose a new strategy to model disease associations using context-sensitive networks (CSNs). We developed a CSN-based phenome-driven approach for disease genetics prediction, and investigated the translational potential of the predicted genes in drug discovery. We constructed CSNs by directly connecting diseases with associated phenotypes. Here, we constructed two CSNs using different data sources; the two networks contain 26 790 and 13 822 nodes respectively. We integrated the CSNs with a genetic functional relationship network and predicted disease genes using a network-based ranking algorithm. For comparison, we built Similarity-Based disease Networks (SBN) using the same disease phenotype data. In a de novo cross validation for 3324 diseases, the CSN-based approach significantly increased the average rank from top 12.6 to top 8.8% for all tested genes comparing with the SBN-based approach ( pdisease using CSNs, and demonstrated that the top-ranked genes are highly relevant to PD pathologenesis. We pin-pointed a top-ranked drug target gene for PD, and found its association with neurodegeneration supported by literature. In summary, CSNs lead to significantly improve the disease genetics prediction comparing with SBNs and provide leads for potential drug targets. nlp.case.edu/public/data/. rxx@case.edu.

  14. Active Drumming Experience Increases Infants' Sensitivity to Audiovisual Synchrony during Observed Drumming Actions.

    Directory of Open Access Journals (Sweden)

    Sarah A Gerson

    Full Text Available In the current study, we examined the role of active experience on sensitivity to multisensory synchrony in six-month-old infants in a musical context. In the first of two experiments, we trained infants to produce a novel multimodal effect (i.e., a drum beat and assessed the effects of this training, relative to no training, on their later perception of the synchrony between audio and visual presentation of the drumming action. In a second experiment, we then contrasted this active experience with the observation of drumming in order to test whether observation of the audiovisual effect was as effective for sensitivity to multimodal synchrony as active experience. Our results indicated that active experience provided a unique benefit above and beyond observational experience, providing insights on the embodied roots of (early music perception and cognition.

  15. Semantic integration by pattern priming: experiment and cortical network model.

    Science.gov (United States)

    Lavigne, Frédéric; Longrée, Dominique; Mayaffre, Damon; Mellet, Sylvie

    2016-12-01

    Neural network models describe semantic priming effects by way of mechanisms of activation of neurons coding for words that rely strongly on synaptic efficacies between pairs of neurons. Biologically inspired Hebbian learning defines efficacy values as a function of the activity of pre- and post-synaptic neurons only. It generates only pair associations between words in the semantic network. However, the statistical analysis of large text databases points to the frequent occurrence not only of pairs of words (e.g., "the way") but also of patterns of more than two words (e.g., "by the way"). The learning of these frequent patterns of words is not reducible to associations between pairs of words but must take into account the higher level of coding of three-word patterns. The processing and learning of pattern of words challenges classical Hebbian learning algorithms used in biologically inspired models of priming. The aim of the present study was to test the effects of patterns on the semantic processing of words and to investigate how an inter-synaptic learning algorithm succeeds at reproducing the experimental data. The experiment manipulates the frequency of occurrence of patterns of three words in a multiple-paradigm protocol. Results show for the first time that target words benefit more priming when embedded in a pattern with the two primes than when only associated with each prime in pairs. A biologically inspired inter-synaptic learning algorithm is tested that potentiates synapses as a function of the activation of more than two pre- and post-synaptic neurons. Simulations show that the network can learn patterns of three words to reproduce the experimental results.

  16. Large Scale Experiments of Multihop Networks in Mobile Scenarios

    Directory of Open Access Journals (Sweden)

    Yacine Benchaïb

    2016-03-01

    Full Text Available This paper presents the latest advances in our research work focused on VIRMANEL and SILUMOD, a couple of tools developed for research in wireless mobile multihop networks. SILUMOD is a domain specific language dedicated to the definition of mobility models. This language contains key- words and special operators that make it easy to define a mobility model and calculate the positions of a trajectory. These positions are sent to VIRMANEL, a tool that man- ages virtual machines corresponding to mobile nodes, emu- lates their movements and the resulting connections and dis- connections, and displays the network evolution to the user, thanks to its graphical user interface. The virtualization ap- proach we take here allows to run real code and to test real protocol implementations without deploying an important experimental platform. For the experimentation of a large number of virtual mobile nodes, we defined and implemented a new algorithm for the nearest neighbor search to find the nodes that are within communication range. We then car- ried out a considerable measurement campaign in order to evaluate the performance of this algorithm. The results show that even with an experiment using a large number of mobile nodes, our algorithm make it possible to evaluate the state of connectivity between mobile nodes within a reasonable time and number of operations.

  17. Analysis, Synthesis and Experiments of Networked Platoons with Communication Constraints

    Directory of Open Access Journals (Sweden)

    Ligang Wu

    2017-02-01

    Full Text Available This paper investigates the analysis and synthesis of networked vehicle platoons with communication delays, packet dropouts and disorders. In order to deal with the effects of the communication constraints, we introduce a novel Smart Data Processor (SDP for each vehicle, by which the latest data packets from logic Data Packet Processor and the matched data packet from its Buffer can be obtained. Based on this mechanism, a leader-predecessor-follower control strategy is proposed. In order to guarantee the asymptotic and string stability, the platoon control problem is transformed into a multi-objective H∞-type synthesis problem with the multiple time-varying delays. A sufficient condition for designing the controller gain is derived by solving a set of linear matrix inequalities. Numerous simulations and experiments with laboratory scale Arduino cars show the efficiency of the proposed methods.

  18. PV-Diesel Hybrid SCADA Experiment Network Design

    Science.gov (United States)

    Kalu, Alex; Durand, S.; Emrich, Carol; Ventre, G.; Wilson, W.; Acosta, R.

    1999-01-01

    The essential features of an experimental network for renewable power system satellite based supervisory, control and data acquisition (SCADA) are communication links, controllers, diagnostic equipment and a hybrid power system. Required components for implementing the network consist of two satellite ground stations, to satellite modems, two 486 PCs, two telephone receivers, two telephone modems, two analog telephone lines, one digital telephone line, a hybrid-power system equipped with controller and a satellite spacecraft. In the technology verification experiment (TVE) conducted by Savannah State University and Florida Solar Energy Center, the renewable energy hybrid system is the Apex-1000 Mini-Hybrid which is equipped with NGC3188 for user interface and remote control and the NGC2010 for monitoring and basic control tasks. This power system is connected to a satellite modem via a smart interface, RS232. Commands are sent to the power system control unit through a control PC designed as PC1. PC1 is thus connected to a satellite model through RS232. A second PC, designated PC2, the diagnostic PC is connected to both satellite modems via separate analog telephone lines for checking modems'health. PC2 is also connected to PC1 via a telephone line. Due to the unavailability of a second ground station for the ACTS, one ground station is used to serve both the sending and receiving functions in this experiment. Signal is sent from the control PC to the Hybrid system at a frequency f(sub 1), different from f(sub 2), the signal from the hybrid system to the control PC. f(sub l) and f(sub 2) are sufficiently separated to avoid interference.

  19. Action Video Game Experience Related to Altered Large-Scale White Matter Networks

    Directory of Open Access Journals (Sweden)

    Diankun Gong

    2017-01-01

    Full Text Available With action video games (AVGs becoming increasingly popular worldwide, the cognitive benefits of AVG experience have attracted continuous research attention over the past two decades. Research has repeatedly shown that AVG experience can causally enhance cognitive ability and is related to neural plasticity in gray matter and functional networks in the brain. However, the relation between AVG experience and the plasticity of white matter (WM network still remains unclear. WM network modulates the distribution of action potentials, coordinating the communication between brain regions and acting as the framework of neural networks. And various types of cognitive deficits are usually accompanied by impairments of WM networks. Thus, understanding this relation is essential in assessing the influence of AVG experience on neural plasticity and using AVG experience as an interventional tool for impairments of WM networks. Using graph theory, this study analyzed WM networks in AVG experts and amateurs. Results showed that AVG experience is related to altered WM networks in prefrontal networks, limbic system, and sensorimotor networks, which are related to cognitive control and sensorimotor functions. These results shed new light on the influence of AVG experience on the plasticity of WM networks and suggested the clinical applicability of AVG experience.

  20. Action Video Game Experience Related to Altered Large-Scale White Matter Networks.

    Science.gov (United States)

    Gong, Diankun; Ma, Weiyi; Gong, Jinnan; He, Hui; Dong, Li; Zhang, Dan; Li, Jianfu; Luo, Cheng; Yao, Dezhong

    2017-01-01

    With action video games (AVGs) becoming increasingly popular worldwide, the cognitive benefits of AVG experience have attracted continuous research attention over the past two decades. Research has repeatedly shown that AVG experience can causally enhance cognitive ability and is related to neural plasticity in gray matter and functional networks in the brain. However, the relation between AVG experience and the plasticity of white matter (WM) network still remains unclear. WM network modulates the distribution of action potentials, coordinating the communication between brain regions and acting as the framework of neural networks. And various types of cognitive deficits are usually accompanied by impairments of WM networks. Thus, understanding this relation is essential in assessing the influence of AVG experience on neural plasticity and using AVG experience as an interventional tool for impairments of WM networks. Using graph theory, this study analyzed WM networks in AVG experts and amateurs. Results showed that AVG experience is related to altered WM networks in prefrontal networks, limbic system, and sensorimotor networks, which are related to cognitive control and sensorimotor functions. These results shed new light on the influence of AVG experience on the plasticity of WM networks and suggested the clinical applicability of AVG experience.

  1. Effects of Prematurity on the Development of Contrast Sensitivity: Testing the Visual Experience Hypothesis

    Science.gov (United States)

    Bosworth, Rain G.; Dobkins, Karen R.

    2013-01-01

    In order to investigate the effects of visual experience on early visual development, the current study compared contrast sensitivity across infants born with different levels of moderate-to-late prematurity. Here the logic is that at any given postterm age, the most premature infants will have the oldest postnatal age. Given that postnatal age is a proxy for visual experience, the visual experience hypothesis predicts that infants who are more premature, yet healthy, should have higher sensitivity. Luminance (light/dark) and chromatic (red/green) contrast sensitivities (CS) were measured in 236 healthy infants (born −10 to +2 weeks relative to due date) between 5 and 32 weeks postterm age from due date and 8 to 38 weeks postnatal from birth date. For chromatic CS, we found clear evidence that infants who were most premature within our sample had the highest sensitivity. Specifically, 4 to 10 additional weeks of visual experience, by virtue of being born early, enhanced chromatic CS. For luminance CS, similar but weaker results were seen. Here, only infants with an additional 6 to 10 weeks of visual experience, and only at later age points in development, showed enhanced sensitivity. However, CS in preterm infants was still below that of fullterm infants with equivalent postnatal age. In sum, these results suggest that chromatic CS is influenced more by prematurity (and possibly visual experience) than is luminance CS, which has implications for differential development of Parvocellular and Magnocellular pathways. PMID:23485427

  2. Sharing for Health: A Study of Chinese Adolescents' Experiences and Perspectives on Using Social Network Sites to Share Health Information.

    Science.gov (United States)

    Zhang, Ni; Teti, Michele; Stanfield, Kellie; Campo, Shelly

    2017-07-01

    This exploratory qualitative study examines Chinese adolescents' health information sharing habits on social network sites. Ten focus group meetings with 76 adolescents, ages 12 to 17 years, were conducted at community-based organizations in Chicago's Chinatown. The research team transcribed the recording and analyzed the transcripts using ATLAS.ti. Chinese adolescents are using different social network sites for various topics of health information including food, physical activity, and so on. Adolescents would share useful and/or interesting health information. Many adolescents raised credibility concerns regarding health information and suggested evaluating the information based on self-experience or intuition, word-of-mouth, or information online. The findings shed lights on future intervention using social network sites to promote health among Chinese adolescents in the United States. Future interventions should provide adolescents with interesting and culturally sensitive health information and educate them to critically evaluate health information on social network sites.

  3. A Comprehensive Sensitivity Analysis of a Data Center Network with Server Virtualization for Business Continuity

    Directory of Open Access Journals (Sweden)

    Tuan Anh Nguyen

    2015-01-01

    Full Text Available Sensitivity assessment of availability for data center networks (DCNs is of paramount importance in design and management of cloud computing based businesses. Previous work has presented a performance modeling and analysis of a fat-tree based DCN using queuing theory. In this paper, we present a comprehensive availability modeling and sensitivity analysis of a DCell-based DCN with server virtualization for business continuity using stochastic reward nets (SRN. We use SRN in modeling to capture complex behaviors and dependencies of the system in detail. The models take into account (i two DCell configurations, respectively, composed of two and three physical hosts in a DCell0 unit, (ii failure modes and corresponding recovery behaviors of hosts, switches, and VMs, and VM live migration mechanism within and between DCell0s, and (iii dependencies between subsystems (e.g., between a host and VMs and between switches and VMs in the same DCell0. The constructed SRN models are analyzed in detail with regard to various metrics of interest to investigate system’s characteristics. A comprehensive sensitivity analysis of system availability is carried out in consideration of the major impacting parameters in order to observe the system’s complicated behaviors and find the bottlenecks of system availability. The analysis results show the availability improvement, capability of fault tolerance, and business continuity of the DCNs complying with DCell network topology. This study provides a basis of designing and management of DCNs for business continuity.

  4. Degree Correlations Optimize Neuronal Network Sensitivity to Sub-Threshold Stimuli.

    Directory of Open Access Journals (Sweden)

    Christian Schmeltzer

    Full Text Available Information processing in the brain crucially depends on the topology of the neuronal connections. We investigate how the topology influences the response of a population of leaky integrate-and-fire neurons to a stimulus. We devise a method to calculate firing rates from a self-consistent system of equations taking into account the degree distribution and degree correlations in the network. We show that assortative degree correlations strongly improve the sensitivity for weak stimuli and propose that such networks possess an advantage in signal processing. We moreover find that there exists an optimum in assortativity at an intermediate level leading to a maximum in input/output mutual information.

  5. Personality and complex brain networks: The role of openness to experience in default network efficiency.

    Science.gov (United States)

    Beaty, Roger E; Kaufman, Scott Barry; Benedek, Mathias; Jung, Rex E; Kenett, Yoed N; Jauk, Emanuel; Neubauer, Aljoscha C; Silvia, Paul J

    2016-02-01

    The brain's default network (DN) has been a topic of considerable empirical interest. In fMRI research, DN activity is associated with spontaneous and self-generated cognition, such as mind-wandering, episodic memory retrieval, future thinking, mental simulation, theory of mind reasoning, and creative cognition. Despite large literatures on developmental and disease-related influences on the DN, surprisingly little is known about the factors that impact normal variation in DN functioning. Using structural equation modeling and graph theoretical analysis of resting-state fMRI data, we provide evidence that Openness to Experience-a normally distributed personality trait reflecting a tendency to engage in imaginative, creative, and abstract cognitive processes-underlies efficiency of information processing within the DN. Across two studies, Openness predicted the global efficiency of a functional network comprised of DN nodes and corresponding edges. In Study 2, Openness remained a robust predictor-even after controlling for intelligence, age, gender, and other personality variables-explaining 18% of the variance in DN functioning. These findings point to a biological basis of Openness to Experience, and suggest that normally distributed personality traits affect the intrinsic architecture of large-scale brain systems. Hum Brain Mapp 37:773-779, 2016. © 2015 Wiley Periodicals, Inc. © 2015 The Authors Human Brain Mapping Published by Wiley Periodicals, Inc.

  6. Multihopping Multilevel Clustering Heterogeneity-Sensitive Optimized Routing Protocol for Wireless Sensor Networks

    Directory of Open Access Journals (Sweden)

    Muhammad Aslam

    2017-01-01

    Full Text Available Effective utilization of energy resources in Wireless Sensor Networks (WSNs has become challenging under uncertain distributed cluster-formation and single-hop intercluster communication capabilities. So, sensor nodes are forced to operate at expensive full rate transmission power level continuously during whole network operation. These challenging network environments experience unwanted phenomena of drastic energy consumption and packet drop. In this paper, we propose an adaptive immune Multihopping Multilevel Clustering (MHMLC protocol that executes a Hybrid Clustering Algorithm (HCA to perform optimal centralized selection of Cluster-Heads (CHs within radius of centrally located Base Station (BS and distributed CHs selection in the rest of network area. HCA of MHMLC also produces optimal intermediate CHs for intercluster multihop communications that develop heterogeneity-aware economical links. This hybrid cluster-formation facilitates the sensors to function at short range transmission power level that enhances link quality and avoids packet drop. The simulation environments produce fair comparison among proposed MHMLC and existing state-of-the-art routing protocols. Experimental results give significant evidence of better performance of the proposed model in terms of network lifetime, stability period, and data delivery ratio.

  7. The Planeterrella experiment: from individual initiative to networking

    Science.gov (United States)

    Lilensten, J.; Provan, G.; Barthelemy, M.; Simon Wedlund, C.; Gronoff, G.; Vanlommel, P.; Brekke, A.; Garnier, P.; Grimald Rochel, S.

    2013-12-01

    Space weather is a relatively new discipline, which is still largely unknown amongst the wider public despite its increasing importance in all of our daily lives. Outreach activities can promote awareness of space weather. In particular the visual beauty and excitement of the aurora make these lights a wonderful inspirational hook to enhance understanding of space weather in a general audience. A century ago, the Norwegian experimental physicist Kristian Birkeland, one of the founding fathers of modern space science, demonstrated with his Terrella experiment the formation of the aurora. Recently, a modernized version of the Terrella has been designed in France. This ';';Planeterrella'' experiment allows the visualization of many phenomena that occur in our space environment. Although the Planeterrella was originally a local project, it has developed to become a very successful international public outreach experiment. We believe that its success is due to mainly two factors (i) the Planeterrella is not patented and the plans are free to any public institute and (ii) the project is widely advertised using national and scientific networks, as well as press releases, books and web sites. Today, nine Planeterrellas are in operation, six more are under construction in five different countries including in the US and several more are being planned. During the last five years, about 55 000 people in Europe have attended live Planeterrella demonstration on the formation of auroral light, the space environment and space weather. Many more have seen the Planeterrella being demonstrated on TV. It is now used for education, outreach, scientific, and artistic purposes. We will describes this process and discuss how the Planeterrella project developed to become an international public outreach phenomenon. We also examine some of the lessons learnt along the way such as patented or not, big or small, automatized or hand-operated, and the cost of the overall project. A star (close

  8. The Planeterrella experiment: from individual initiative to networking

    Directory of Open Access Journals (Sweden)

    Garnier Pierre

    2013-02-01

    Full Text Available Space weather is a relatively new discipline, which is still largely unknown amongst the wider public despite its increasing importance in all of our daily lives. Outreach activities can promote awareness of space weather. In particular the visual beauty and excitement of the aurora make these lights a wonderful inspirational hook to enhance understanding of space weather in a general audience. A century ago, the Norwegian experimental physicist Kristian Birkeland, one of the founding fathers of modern space science, demonstrated with his Terrella experiment the formation of the aurora. Recently, a modernized version of the Terrella has been designed. This “Planeterrella” experiment allows the visualization of many phenomena that occur in our space environment. Although the Planeterrella was originally a local project, it has developed to become a very successful international public outreach experiment. We believe that its success is due to mainly two factors (i the Planeterrella is not patented and the plans are free to any public institute and (ii the project is widely advertised using national and European scientific networks such as COST ES 0803, as well as press releases, books and web sites. Today, seven Planeterrellas are in operation, four more are under construction in four different countries and several more are being planned. During the last five years, about 50 000 people in Europe have attended live Planeterrella demonstration on the formation of auroral light, the space environment and space weather. Many more have seen the Planeterrella being demonstrated on TV. The Planeterrella received the first international prize for outreach activities from the Europlanet Framework 7 program in 2010 and the French Ministry of Science outreach prize “Le goût des sciences” in November 2012. This paper describes the process that led to the construction of the first Planeterrella and discusses how the Planeterrella project developed

  9. Factor Structure of Early Smoking Experiences and Associations with Smoking Behavior: Valence or Sensitivity Model?

    Science.gov (United States)

    Baggio, Stéphanie; Studer, Joseph; Deline, Stéphane; Mohler-Kuo, Meichun; Daeppen, Jean-Bernard; Gmel, Gerhard

    2013-01-01

    The Early Smoking Experience (ESE) questionnaire is the most widely used questionnaire to assess initial subjective experiences of cigarette smoking. However, its factor structure is not clearly defined and can be perceived from two main standpoints: valence, or positive and negative experiences, and sensitivity to nicotine. This article explores the ESE’s factor structure and determines which standpoint was more relevant. It compares two groups of young Swiss men (German- and French-speaking). We examined baseline data on 3,368 tobacco users from a representative sample in the ongoing Cohort Study on Substance Use Risk Factors (C-SURF). ESE, continued tobacco use, weekly smoking and nicotine dependence were assessed. Exploratory structural equation modeling (ESEM) and structural equation modeling (SEM) were performed. ESEM clearly distinguished positive experiences from negative experiences, but negative experiences were divided in experiences related to dizziness and experiences related to irritations. SEM underlined the reinforcing effects of positive experiences, but also of experiences related to dizziness on nicotine dependence and weekly smoking. The best ESE structure for predictive accuracy of experiences on smoking behavior was a compromise between the valence and sensitivity standpoints, which showed clinical relevance. PMID:24287854

  10. Factor Structure of Early Smoking Experiences and Associations with Smoking Behavior: Valence or Sensitivity Model?

    Directory of Open Access Journals (Sweden)

    Stéphanie Baggio

    2013-11-01

    Full Text Available The Early Smoking Experience (ESE questionnaire is the most widely used questionnaire to assess initial subjective experiences of cigarette smoking. However, its factor structure is not clearly defined and can be perceived from two main standpoints: valence, or positive and negative experiences, and sensitivity to nicotine. This article explores the ESE’s factor structure and determines which standpoint was more relevant. It compares two groups of young Swiss men (German- and French-speaking. We examined baseline data on 3,368 tobacco users from a representative sample in the ongoing Cohort Study on Substance Use Risk Factors (C-SURF. ESE, continued tobacco use, weekly smoking and nicotine dependence were assessed. Exploratory structural equation modeling (ESEM and structural equation modeling (SEM were performed. ESEM clearly distinguished positive experiences from negative experiences, but negative experiences were divided in experiences related to dizziness and experiences related to irritations. SEM underlined the reinforcing effects of positive experiences, but also of experiences related to dizziness on nicotine dependence and weekly smoking. The best ESE structure for predictive accuracy of experiences on smoking behavior was a compromise between the valence and sensitivity standpoints, which showed clinical relevance.

  11. Sensitivity of the SHiP experiment to a light scalar particle mixing with the Higgs

    CERN Document Server

    Lanfranchi, Gaia

    2017-01-01

    This conceptual study shows the ultimate sensitivity of the SHiP experiment for the search of a light scalar particle mixing with the Higgs for a dataset corresponding to 5-years of SHiP operation at a nominal intensity of 4 1013 protons on target per second. The sensitivity as a function of the length of the vessel and of its distance from the target as well as a function of the background contamination is also studied.

  12. Gradient-Enhanced Triple-Resonance Three-Dimensional NMR Experiments with Improved Sensitivity

    Science.gov (United States)

    Muhandiram, D. R.; Kay, L. E.

    1994-03-01

    The sensitivities of a number of gradient and nongradient versions of triple-resonance experiments are compared by quantitating the signal-to-noise ratios in spectra recorded on Cellulomonas fimi cellulose binding domain (110 amino acids), Xenopus laevis calmodulin (148 amino acids), Mycococcus xanthus protein S (173 amino acids), and a 93-amino acid fragment of protein S. It is shown that it is possible to construct sensitivity-enhanced gradient experiments, with 15N selection achieved via pulsed field gradients, that are as sensitive as their sensitivity-enhanced nongradient counterparts and significantly more sensitive than other gradient approaches. These sequences are very closely related to the family of improved-sensitivity sequences proposed by Rance and co-workers (A. G. Palmer, J. Cavanagh, P. E. Wright, and M. Rance, J. Magn. Reson.93, 151, 1991). The use of gradients greatly improves the quality of water suppression and reduces both the number of artifacts and the phase-cycling requirements at no cost in sensitivity for the proteins considered in this study.

  13. Networks as Drivers for Innovation – Experiences from Food Networks in Canada and New Zealand

    Directory of Open Access Journals (Sweden)

    Karen Hamann

    2013-02-01

    Full Text Available A common feature among networks is the focus on innovation but the approach to driving innovation and to supporting companies’ innovation work differs widely between networks. Some networks strive to be THE forum of an industry, andthese networks generally focus on promoting innovations that are market‐ready. Networks with a defined objective of promoting research‐driven innovation must have different network organisations from the forum‐oriented networks. Research shows that networks promoting research‐driven innovation also lead to patent applications and should have activities towards commercialisation support. This paper compares four networks from Canada and New Zealand in order to identify examples of how networks with different structures and objectives can support innovation in agri‐food companies. The paper is an empirical contribution to the research area of networks and innovation.

  14. Sensitivity Analysis of Wavelet Neural Network Model for Short-Term Traffic Volume Prediction

    Directory of Open Access Journals (Sweden)

    Jinxing Shen

    2013-01-01

    Full Text Available In order to achieve a more accurate and robust traffic volume prediction model, the sensitivity of wavelet neural network model (WNNM is analyzed in this study. Based on real loop detector data which is provided by traffic police detachment of Maanshan, WNNM is discussed with different numbers of input neurons, different number of hidden neurons, and traffic volume for different time intervals. The test results show that the performance of WNNM depends heavily on network parameters and time interval of traffic volume. In addition, the WNNM with 4 input neurons and 6 hidden neurons is the optimal predictor with more accuracy, stability, and adaptability. At the same time, a much better prediction record will be achieved with the time interval of traffic volume are 15 minutes. In addition, the optimized WNNM is compared with the widely used back-propagation neural network (BPNN. The comparison results indicated that WNNM produce much lower values of MAE, MAPE, and VAPE than BPNN, which proves that WNNM performs better on short-term traffic volume prediction.

  15. Accelerating Innovation Through Coopetition: The Innovation Learning Network Experience.

    Science.gov (United States)

    McCarthy, Chris; Ford Carleton, Penny; Krumpholz, Elizabeth; Chow, Marilyn P

    Coopetition, the simultaneous pursuit of cooperation and competition, is a growing force in the innovation landscape. For some organizations, the primary mode of innovation continues to be deeply secretive and highly competitive, but for others, a new style of shared challenges, shared purpose, and shared development has become a superior, more efficient way of working to accelerate innovation capabilities and capacity. Over the last 2 decades, the literature base devoted to coopetition has gradually expanded. However, the field is still in its infancy. The majority of coopetition research is qualitative, primarily consisting of case studies. Few studies have addressed the nonprofit sector or service industries such as health care. The authors believe that this article may offer a unique perspective on coopetition in the context of a US-based national health care learning alliance designed to accelerate innovation, the Innovation Learning Network or ILN. The mission of the ILN is to "Share the joy and pain of innovation," accelerating innovation by sharing solutions, teaching techniques, and cultivating friendships. These 3 pillars (sharing, teaching, and cultivating) form the foundation for coopetition within the ILN. Through the lens of coopetition, we examine the experience of the ILN over the last 10 years and provide case examples that illustrate the benefits and challenges of coopetition in accelerating innovation in health care.

  16. [Local public health networks. Apropos of an experience].

    Science.gov (United States)

    Guix, Joan; Bocio, Ana; Ferràs, Joaquim; Margalef, Jordi; Osanz, Anna C; Serrano, Mónica; Sentenà, Anna

    2013-01-01

    Public health action on a territory is complex and requires the involvement of multiple actors, who do not always act coordinately. Networks of organizations structures including the whole of the local actors facilitate the generation of synergies and enable greater effectiveness and efficiency of the joint action from the different actors on a same landscape. We present 3 years experience of four Public Health Committees in a region of Catalonia (Spain), composed by the main actors in public health planning. Each of the committees is organized on a plenary and working groups on issues arising from the regional health diagnosis, and coincident with the Health Plan of the Region. Coordination in no case implies the loss or dilution of the firm of the actor generator of intervention initiative in public health, but their empowerment and collaboration by the other actors. In conclusion welcomes the creation of a culture of collaboration and synergies between the different organizations concerned. Lack of specificity is observed in establishing operational objectives, and the need for greater coordination and involvement of the components of the various working groups. Copyright © 2012 SESPAS. Published by Elsevier Espana. All rights reserved.

  17. Personality and complex brain networks: The role of openness to experience in default network efficiency

    Science.gov (United States)

    Kaufman, Scott Barry; Benedek, Mathias; Jung, Rex E.; Kenett, Yoed N.; Jauk, Emanuel; Neubauer, Aljoscha C.; Silvia, Paul J.

    2015-01-01

    Abstract The brain's default network (DN) has been a topic of considerable empirical interest. In fMRI research, DN activity is associated with spontaneous and self‐generated cognition, such as mind‐wandering, episodic memory retrieval, future thinking, mental simulation, theory of mind reasoning, and creative cognition. Despite large literatures on developmental and disease‐related influences on the DN, surprisingly little is known about the factors that impact normal variation in DN functioning. Using structural equation modeling and graph theoretical analysis of resting‐state fMRI data, we provide evidence that Openness to Experience—a normally distributed personality trait reflecting a tendency to engage in imaginative, creative, and abstract cognitive processes—underlies efficiency of information processing within the DN. Across two studies, Openness predicted the global efficiency of a functional network comprised of DN nodes and corresponding edges. In Study 2, Openness remained a robust predictor—even after controlling for intelligence, age, gender, and other personality variables—explaining 18% of the variance in DN functioning. These findings point to a biological basis of Openness to Experience, and suggest that normally distributed personality traits affect the intrinsic architecture of large‐scale brain systems. Hum Brain Mapp 37:773–779, 2016. © 2015 Wiley Periodicals, Inc. PMID:26610181

  18. Efficiency of Software Testing Techniques: A Controlled Experiment Replication and Network Meta-analysis

    Directory of Open Access Journals (Sweden)

    Omar S. Gómez

    2017-07-01

    Full Text Available Background: Common approaches to software verification include static testing techniques, such as code reading, and dynamic testing techniques, such as black-box and white-box testing. Objective: With the aim of gaining a~better understanding of software testing techniques, a~controlled experiment replication and the synthesis of previous experiments which examine the efficiency of code reading, black-box and white-box testing techniques were conducted. Method: The replication reported here is composed of four experiments in which instrumented programs were used. Participants randomly applied one of the techniques to one of the instrumented programs. The outcomes were synthesized with seven experiments using the method of network meta-analysis (NMA. Results: No significant differences in the efficiency of the techniques were observed. However, it was discovered the instrumented programs had a~significant effect on the efficiency. The NMA results suggest that the black-box and white-box techniques behave alike; and the efficiency of code reading seems to be sensitive to other factors. Conclusion: Taking into account these findings, the Authors suggest that prior to carrying out software verification activities, software engineers should have a~clear understanding of the software product to be verified; they can apply either black-box or white-box testing techniques as they yield similar defect detection rates.

  19. General-purpose computer networks and resource sharing in ERDA. Volume 3. Remote resource-sharing experience and findings

    Energy Technology Data Exchange (ETDEWEB)

    1977-07-15

    The investigation focused on heterogeneous networks in which a variety of dissimilar computers and operating systems were interconnected nationwide. Homogeneous networks, such as MFE net and SACNET, were not considered since they could not be used for general purpose resource sharing. Issues of privacy and security are of concern in any network activity. However, consideration of privacy and security of sensitive data arise to a much lesser degree in unclassified scientific research than in areas involving personal or proprietary information. Therefore, the existing mechanisms at individual sites for protecting sensitive data were relied on, and no new protection mechanisms to prevent infringement of privacy and security were attempted. Further development of ERDA networking will need to incorporate additional mechanisms to prevent infringement of privacy. The investigation itself furnishes an excellent example of computational resource sharing through a heterogeneous network. More than twenty persons, representing seven ERDA computing sites, made extensive use of both ERDA and non-ERDA computers in coordinating, compiling, and formatting the data which constitute the bulk of this report. Volume 3 analyzes the benefits and barriers encountered in actual resource sharing experience, and provides case histories of typical applications.

  20. Researching Design, Experience and Practice of Networked Learning

    DEFF Research Database (Denmark)

    Hodgson, Vivien; de Laat, Maarten; McConnell, David

    2014-01-01

    and final section draws attention to a growing topic of interest within networked learning: that of networked learning in informal practices. In addition, we provide a reflection on the theories, methods and settings featured in the networked learning research of the chapters. We conclude the introduction......In the introductory chapter, we explore how networked learning has developed in recent years by summarising and discussing the research presented in the chapters of the book. The chapters are structured in three sections, each highlighting a particular aspect of practice. The first section focuses...

  1. The Role of Sensitizing Experiences in Music Performance Anxiety in Adolescent Musicians

    Science.gov (United States)

    Osborne, Margaret S.; Kenny, Dianna T.

    2008-01-01

    Aversive performance incidents play a role in the development of some anxiety disorders. The role of sensitizing experiences in the development of music performance anxiety (MPA) in adolescent music students has not yet been explored. Two-hundred-and-ninety-eight music students were asked to provide written descriptions of their worst performance,…

  2. Applying Information Theory to Neuronal Networks: From Theory to Experiments

    NARCIS (Netherlands)

    Jung, T.I.; Vogiatzian, F.; Har-Shemesh, O.; Fitzsimons, C.P.; Quax, R.

    2014-01-01

    Information-theory is being increasingly used to analyze complex, self-organizing processes on networks, predominantly in analytical and numerical studies. Perhaps one of the most paradigmatic complex systems is a network of neurons, in which cognition arises from the information storage, transfer,

  3. Stillbirth Collaborative Research Network: design, methods and recruitment experience.

    Science.gov (United States)

    Parker, Corette B; Hogue, Carol J R; Koch, Matthew A; Willinger, Marian; Reddy, Uma M; Thorsten, Vanessa R; Dudley, Donald J; Silver, Robert M; Coustan, Donald; Saade, George R; Conway, Deborah; Varner, Michael W; Stoll, Barbara; Pinar, Halit; Bukowski, Radek; Carpenter, Marshall; Goldenberg, Robert

    2011-09-01

    The Stillbirth Collaborative Research Network (SCRN) has conducted a multisite, population-based, case-control study, with prospective enrollment of stillbirths and livebirths at the time of delivery. This paper describes the general design, methods and recruitment experience. The SCRN attempted to enroll all stillbirths and a representative sample of livebirths occurring to residents of pre-defined geographical catchment areas delivering at 59 hospitals associated with five clinical sites. Livebirths <32 weeks gestation and women of African descent were oversampled. The recruitment hospitals were chosen to ensure access to at least 90% of all stillbirths and livebirths to residents of the catchment areas. Participants underwent a standardised protocol including maternal interview, medical record abstraction, placental pathology, biospecimen testing and, in stillbirths, post-mortem examination. Recruitment began in March 2006 and was completed in September 2008 with 663 women with a stillbirth and 1932 women with a livebirth enrolled, representing 69% and 63%, respectively, of the women identified. Additional surveillance for stillbirths continued until June 2009 and a follow-up of the case-control study participants was completed in December 2009. Among consenting women, there were high consent rates for the various study components. For the women with stillbirths, 95% agreed to a maternal interview, chart abstraction and a placental pathological examination; 91% of the women with a livebirth agreed to all of these components. Additionally, 84% of the women with stillbirths agreed to a fetal post-mortem examination. This comprehensive study is poised to systematically study a wide range of potential causes of, and risk factors for, stillbirths and to better understand the scope and incidence of the problem. © 2011 Blackwell Publishing Ltd.

  4. Business communication in social networks: Content management and experiences

    Directory of Open Access Journals (Sweden)

    Miguel Ángel Nicolás

    2014-11-01

    Full Text Available Currently, management of communication in social networks has become an indispensable strategic activity and contributes directly to change the mode of relationship between business and its stakeholders. The first section of this paper presents a brief analysis of the results reported in different specialized national studies in social networks. We analyse the general activities that users prefer to do and activities that users value most brands on networks. If an organization wants to successfully manage their communication in social networks is very important to know the behaviour of the users and design strategies based on their status and economic activity. This paper presents a brief analysis of social branding through the classification of different corporate content posted on their networks.

  5. Experiments on neural network architectures for fuzzy logic

    Science.gov (United States)

    Keller, James M.

    1991-01-01

    The use of fuzzy logic to model and manage uncertainty in a rule-based system places high computational demands on an inference engine. In an earlier paper, the authors introduced a trainable neural network structure for fuzzy logic. These networks can learn and extrapolate complex relationships between possibility distributions for the antecedents and consequents in the rules. Here, the power of these networks is further explored. The insensitivity of the output to noisy input distributions (which are likely if the clauses are generated from real data) is demonstrated as well as the ability of the networks to internalize multiple conjunctive clause and disjunctive clause rules. Since different rules with the same variables can be encoded in a single network, this approach to fuzzy logic inference provides a natural mechanism for rule conflict resolution.

  6. Building Cultural Sensitivity and Interprofessional Collaboration Through a Study Abroad Experience.

    Science.gov (United States)

    Gilliland, Irene; Attridge, Russell T; Attridge, Rebecca L; Maize, David F; McNeill, Jeanette

    2016-01-01

    Study abroad (SA) experiences for health professions students may be used to heighten cultural sensitivity to future patients and incorporate interprofessional education (IPE). Two groups of nursing and pharmacy students participated in an SA elective over a 2-year period, traveling to China and India. Both groups improved significantly in knowledge, awareness, and skills following the travel experiences. Student reflections indicate that the SA experience was transformative, changing their views of travel, other cultures, personal environment, collaboration with other health professionals, and themselves. Use of SA programs is a novel method to encourage IPE, with a focus on enhancing the acquisition of cultural competency skills. Copyright 2016, SLACK Incorporated.

  7. [Sex- and gender-sensitive research in epidemiology and medicine: how can this be achieved? Aims and first results of the network "Sex-/Gender-Sensitive Research in Epidemiology, Neurosciences and Genetics/Cancer Research"].

    Science.gov (United States)

    Jahn, I; Gansefort, D; Kindler-Röhrborn, A; Pfleiderer, B

    2014-09-01

    It is considered general knowledge among physicians and epidemiologists that biological and social aspects associated with being male or female have a strong influence on health and disease. Integrating these aspects into research is necessary to counteract the problems--including ethical problems--resulting from a different evidence basis for men and women. From January 2011 to June 2014 the Federal Ministry of Education and Research supported the network "Sex-/Gender-Sensitive Research in Epidemiology, Neuroscience and Genetics/Cancer Research" with three subprojects, which aimed to promote gender-sensitive research practices. The concepts and results are presented in this article. The subproject gathered data (literature analyses, questionnaires) and offered programs for young scientists. Experiences and results were collected and generalized, for instance, in the form of definitions of terms. 50 young scientists have taken part in the training program, identifying associations and barriers in sex-/gender-sensitive research. Among others, a working definition for "sex-/gender-sensitive research" was developed, as well as definitions for the terms "sex-specific" (for biological characteristics that are specific to men or women) and "sex-/gender-dependent" or "sex-/gender-associated" (for biological and social factors, for which the extent of occurrence differs between the sexes). The concepts realized by the network are well suited to stimulate further development and discussions. The definition of terms is an important base for a productive and high-yielding interdisciplinary collaboration.

  8. Robust artificial neural network for reliability and sensitivity analyses of complex non-linear systems.

    Science.gov (United States)

    Oparaji, Uchenna; Sheu, Rong-Jiun; Bankhead, Mark; Austin, Jonathan; Patelli, Edoardo

    2017-12-01

    Artificial Neural Networks (ANNs) are commonly used in place of expensive models to reduce the computational burden required for uncertainty quantification, reliability and sensitivity analyses. ANN with selected architecture is trained with the back-propagation algorithm from few data representatives of the input/output relationship of the underlying model of interest. However, different performing ANNs might be obtained with the same training data as a result of the random initialization of the weight parameters in each of the network, leading to an uncertainty in selecting the best performing ANN. On the other hand, using cross-validation to select the best performing ANN based on the ANN with the highest R2 value can lead to biassing in the prediction. This is as a result of the fact that the use of R2 cannot determine if the prediction made by ANN is biased. Additionally, R2 does not indicate if a model is adequate, as it is possible to have a low R2 for a good model and a high R2 for a bad model. Hence, in this paper, we propose an approach to improve the robustness of a prediction made by ANN. The approach is based on a systematic combination of identical trained ANNs, by coupling the Bayesian framework and model averaging. Additionally, the uncertainties of the robust prediction derived from the approach are quantified in terms of confidence intervals. To demonstrate the applicability of the proposed approach, two synthetic numerical examples are presented. Finally, the proposed approach is used to perform a reliability and sensitivity analyses on a process simulation model of a UK nuclear effluent treatment plant developed by National Nuclear Laboratory (NNL) and treated in this study as a black-box employing a set of training data as a test case. This model has been extensively validated against plant and experimental data and used to support the UK effluent discharge strategy. Copyright © 2017 Elsevier Ltd. All rights reserved.

  9. Sensitivity of the International Monitoring System infrasound network to elevated sources: a western Eurasia case study

    Science.gov (United States)

    Nippress, Alexandra; Green, David N.

    2017-11-01

    For the past 5 years (2010-2015) infrasound arrivals have been included in International Data Centre analyst-reviewed bulletins of events detected across the International Monitoring System (IMS). In western Eurasia, there are clusters of up to 268 events that consist of only infrasound arrivals (no associated seismic phases). These clusters are of unknown origin, although one in the North Sea region is associated with sonic booms from supersonic aircraft activity. IMS data for 17 North Sea events are analysed and compared with data from the Large Aperture Infrasound Array in the Netherlands to support the existence of these events and to determine common characteristics. Three other large clusters in western Eurasia are also identified and studied and show similar characteristics to the North Sea events, indicative of supersonic aircraft activity. The IMS infrasound network is shown to be particularly sensitive to sonic booms because the elevated source height reduces the anisotropy of infrasonic propagation within a stratospheric duct and allows for episodic upwind propagation. This episodic upwind propagation in addition to the prevailing downwind propagation, leads to clusters of Reviewed Event Bulletin events with constrained locations in western Eurasia region during the summer months. In the winter months, the recorded arrivals suggest that episodic upwind propagation is not as prevalent. Propagation modelling indicates that the subsequent unidirectional propagation, combined with the sparseness of the IMS network, leads to elongated lines of estimated event locations.

  10. Multimedia over cognitive radio networks algorithms, protocols, and experiments

    CERN Document Server

    Hu, Fei

    2014-01-01

    PrefaceAbout the EditorsContributorsNetwork Architecture to Support Multimedia over CRNA Management Architecture for Multimedia Communication in Cognitive Radio NetworksAlexandru O. Popescu, Yong Yao, Markus Fiedler , and Adrian P. PopescuPaving a Wider Way for Multimedia over Cognitive Radios: An Overview of Wideband Spectrum Sensing AlgorithmsBashar I. Ahmad, Hongjian Sun, Cong Ling, and Arumugam NallanathanBargaining-Based Spectrum Sharing for Broadband Multimedia Services in Cognitive Radio NetworkYang Yan, Xiang Chen, Xiaofeng Zhong, Ming Zhao, and Jing WangPhysical Layer Mobility Challen

  11. Synaptic rewiring of stress-sensitive neurons by early-life experience: a mechanism for resilience?

    Science.gov (United States)

    Singh-Taylor, Akanksha; Korosi, Aniko; Molet, Jenny; Gunn, Benjamin G; Baram, Tallie Z

    2015-01-01

    Genes and environment interact to influence cognitive and emotional functions throughout life. Early-life experiences in particular contribute to vulnerability or resilience to a number of emotional and cognitive illnesses in humans. In rodents, early-life experiences directly lead to resilience or vulnerability to stress later in life, and influence the development of cognitive and emotional deficits. The mechanisms for the enduring effects of early-life experiences on cognitive and emotional outcomes are not completely understood. Here, we present emerging information supporting experience-dependent modulation of the number and efficacy of synaptic inputs onto stress-sensitive neurons. This synaptic 'rewiring', in turn, may influence the expression of crucial neuronal genes. The persistent changes in gene expression in resilient versus vulnerable rodent models are likely maintained via epigenetic mechanisms. Thus, early-life experience may generate resilience by altering synaptic input to neurons, which informs them to modulate their epigenetic machinery.

  12. Enhancing collaborative intrusion detection networks against insider attacks using supervised intrusion sensitivity-based trust management model

    DEFF Research Database (Denmark)

    Li, Wenjuan; Meng, Weizhi; Kwok, Lam-For

    2017-01-01

    To defend against complex attacks, collaborative intrusion detection networks (CIDNs) have been developed to enhance the detection accuracy, which enable an IDS to collect information and learn experience from others. However, this kind of networks is vulnerable to malicious nodes which are utili...

  13. Wearable and Transparent Capacitive Strain Sensor with High Sensitivity Based on Patterned Ag Nanowire Networks.

    Science.gov (United States)

    Kim, Seung-Rok; Kim, Jin-Hoon; Park, Jin-Woo

    2017-08-09

    In this study, a transparent and stretchable thin-film capacitive strain sensor based on patterned Ag nanowire networks (AgNWs) was successfully fabricated. The AgNWs were patterned using a capillary force lithography (CFL) method and were embedded onto the surface of the polydimethylsiloxane substrate. The strain (ε) sensitivity of the capacitive strain sensor was controlled and enhanced by patterning the AgNWs into electrodes with an interdigitated shape. The interdigitated capacitive strain sensor (ICSS) is expected to have -1.57 gauge factor (GF) at 30% ε by calculation, which is much higher than the sensitivity of typical parallel-plate-type capacitive strain sensors. Because of the interdigitated pattern of the electrodes, the GF of the ICSS was increased up to -2.0. The ICSS had no hysteresis behavior up to ε values of 15% and showed stable ε sensing performance during the repeated stretching test at ε values of 10% for 1000 cycles. Furthermore, there was no cross talk between ε and pressure sensing in the AgNW-based ICSS, which was found to be insensitive to externally applied pressure. The ICSS was then used to detect the finger and wrist muscle motions of the human body to simulate its application to large and small ε sensing.

  14. RMT focal plane sensitivity to seismic network geometry and faulting style

    Science.gov (United States)

    Johnson, Kendra L.; Hayes, Gavin; Herrmann, Robert B.; Benz, Harley M.; McNamara, Daniel E.; Bergman, Eric A.

    2016-01-01

    Modern tectonic studies often use regional moment tensors (RMTs) to interpret the seismotectonic framework of an earthquake or earthquake sequence; however, despite extensive use, little existing work addresses RMT parameter uncertainty. Here, we quantify how network geometry and faulting style affect RMT sensitivity. We examine how data-model fits change with fault plane geometry (strike and dip) for varying station configurations. We calculate the relative data fit for incrementally varying geometries about a best-fitting solution, applying our workflow to real and synthetic seismograms for both real and hypothetical station distributions and earthquakes. Initially, we conduct purely observational tests, computing RMTs from synthetic seismograms for hypothetical earthquakes and a series of well-behaved network geometries. We then incorporate real data and station distributions from the International Maule Aftershock Deployment (IMAD), which recorded aftershocks of the 2010 MW 8.8 Maule earthquake, and a set of regional stations capturing the ongoing earthquake sequence in Oklahoma and southern Kansas. We consider RMTs computed under three scenarios: (1) real seismic records selected for high data quality; (2) synthetic seismic records with noise computed for the observed source-station pairings and (3) synthetic seismic records with noise computed for all possible station-source pairings. To assess RMT sensitivity for each test, we observe the ‘fit falloff’, which portrays how relative fit changes when strike or dip varies incrementally; we then derive the ranges of acceptable strikes and dips by identifying the span of solutions with relative fits larger than 90 per cent of the best fit. For the azimuthally incomplete IMAD network, Scenario 3 best constrains fault geometry, with average ranges of 45° and 31° for strike and dip, respectively. In Oklahoma, Scenario 3 best constrains fault dip with an average range of 46°; however, strike is best constrained

  15. Social networks of experientially similar others: formation, activation, and consequences of network ties on the health care experience.

    Science.gov (United States)

    Gage, Elizabeth A

    2013-10-01

    Research documents that interactions among experientially similar others (individuals facing a common stressor) shape health care behavior and ultimately health outcomes. However, we have little understanding of how ties among experientially similar others are formed, what resources and information flows through these networks, and how network embeddedness shapes health care behavior. This paper uses in-depth interviews with 76 parents of pediatric cancer patients to examine network ties among experientially similar others after a serious medical diagnosis. Interviews were conducted between August 2009 and May 2011. Findings demonstrate that many parents formed ties with other families experiencing pediatric cancer, and that information and resources were exchanged during the everyday activities associated with their child's care. Network flows contained emotional support, caregiving strategies, information about second opinions, health-related knowledge, and strategies for navigating the health care system. Diffusion of information, resources, and support occurred through explicit processes (direct information and support exchanges) and implicit processes (parents learning through observing other families). Network flows among parents shaped parents' perceptions of the health care experience and their role in their child's care. These findings contribute to the social networks and social support literatures by elucidating the mechanisms through which network ties among experientially similar others influence health care behavior and experiences. Copyright © 2012 Elsevier Ltd. All rights reserved.

  16. Performance of high-resolution position-sensitive detectors developed for storage-ring decay experiments

    Energy Technology Data Exchange (ETDEWEB)

    Yamaguchi, T., E-mail: yamaguti@phy.saitama-u.ac.jp [Department of Physics, Saitama University, Saitama 338-8570 (Japan); Suzaki, F. [Department of Physics, Saitama University, Saitama 338-8570 (Japan); Izumikawa, T. [RI Center, Niigata University, Niigata 951-8510 (Japan); Miyazawa, S. [Department of Physics, Saitama University, Saitama 338-8570 (Japan); Morimoto, K. [RIKEN Nishina Center, Wako, Saitama 351-0198 (Japan); Suzuki, T. [Department of Physics, Saitama University, Saitama 338-8570 (Japan); Tokanai, F. [Department of Physics, Yamagata University, Yamagata 990-8560 (Japan); Furuki, H.; Ichihashi, N.; Ichikawa, C. [Department of Physics, Saitama University, Saitama 338-8570 (Japan); Kitagawa, A. [National Institute of Radiological Sciences, Chiba 263-8555 (Japan); Kuboki, T. [Department of Physics, Saitama University, Saitama 338-8570 (Japan); Momota, S. [School of Environmental Science and Engineering, Kochi University of Technology, Kochi 782-8502 (Japan); Nagae, D. [Institute of Physics, University of Tsukuba, Ibaraki 305-8571 (Japan); Nagashima, M.; Nakamura, Y. [Department of Physics, Niigata University, Niigata 950-2181 (Japan); Nishikiori, R.; Niwa, T. [Institute of Physics, University of Tsukuba, Ibaraki 305-8571 (Japan); Ohtsubo, T. [Department of Physics, Niigata University, Niigata 950-2181 (Japan); Ozawa, A. [Institute of Physics, University of Tsukuba, Ibaraki 305-8571 (Japan); and others

    2013-12-15

    Highlights: • Position-sensitive detectors were developed for storage-ring decay spectroscopy. • Fiber scintillation and silicon strip detectors were tested with heavy ion beams. • A new fiber scintillation detector showed an excellent position resolution. • Position and energy detection by silicon strip detectors enable full identification. -- Abstract: As next generation spectroscopic tools, heavy-ion cooler storage rings will be a unique application of highly charged RI beam experiments. Decay spectroscopy of highly charged rare isotopes provides us important information relevant to the stellar conditions, such as for the s- and r-process nucleosynthesis. In-ring decay products of highly charged RI will be momentum-analyzed and reach a position-sensitive detector set-up located outside of the storage orbit. To realize such in-ring decay experiments, we have developed and tested two types of high-resolution position-sensitive detectors: silicon strips and scintillating fibers. The beam test experiments resulted in excellent position resolutions for both detectors, which will be available for future storage-ring experiments.

  17. 12th Rencontres du Vietnam : High Sensitivity Experiments Beyond the Standard Model

    CERN Document Server

    2016-01-01

    The goal of this workshop is to gather researchers, theoreticians, experimentalists and young scientists searching for physics beyond the Standard Model of particle physics using high sensitivity experiments. The standard model has been very successful in describing the particle physics world; the Higgs-Englert-Brout boson discovery is its last major discovery. Complementary to the high energy frontier explored at colliders, real opportunities for discovery exist at the precision frontier, testing fundamental symmetries and tracking small SM deviations.

  18. Social Networking Sites' Influence on Travelers' Authentic Experience a Case Study of Couch Surfing

    Science.gov (United States)

    Liu, Xiao

    2013-01-01

    This study explored travelers' experiences in the era of network hospitality 2.0 using CouchSurfing.org as a case study. The following research questions guided this study: 1) what experience does CouchSurfing create for travelers before, during and after their travel? 2) how does couch surfers' experience relate to authenticity in context of…

  19. Network Enabled Operations: The Experiences of Senior Canadian Commanders

    Science.gov (United States)

    2006-03-31

    réseaux technologiques, et leur valeur les uns par rapport aux autres. Les commandants interrogés reconnaissent que les opérations actuelles nécessitent à...the best basis for CF transformation to build upon? • How does one go about creating an effective social network in joint and multinational...environments? • Is the presence or absence of an effective social network a factor in the success of an operation? • Was there any confusion evident

  20. Interim Service ISDN Satellite (ISIS) network model for advanced satellite designs and experiments

    Science.gov (United States)

    Pepin, Gerard R.; Hager, E. Paul

    1991-01-01

    The Interim Service Integrated Services Digital Network (ISDN) Satellite (ISIS) Network Model for Advanced Satellite Designs and Experiments describes a model suitable for discrete event simulations. A top-down model design uses the Advanced Communications Technology Satellite (ACTS) as its basis. The ISDN modeling abstractions are added to permit the determination and performance for the NASA Satellite Communications Research (SCAR) Program.

  1. A Network-Based Model of Oncogenic Collaboration for Prediction of Drug Sensitivity

    Science.gov (United States)

    Laderas, Ted G.; Heiser, Laura M.; Sönmez, Kemal

    2015-01-01

    Tumorigenesis is a multi-step process, involving the acquisition of multiple oncogenic mutations that transform cells, resulting in systemic dysregulation that enables proliferation, invasion, and other cancer hallmarks. The goal of precision medicine is to identify therapeutically-actionable mutations from large-scale omic datasets. However, the multiplicity of oncogenes required for transformation, known as oncogenic collaboration, makes assigning effective treatments difficult. Motivated by this observation, we propose a new type of oncogenic collaboration where mutations in genes that interact with an oncogene may contribute to the oncogene’s deleterious potential, a new genomic feature that we term “surrogate oncogenes.” Surrogate oncogenes are representatives of these mutated subnetworks that interact with oncogenes. By mapping mutations to a protein–protein interaction network, we determine the significance of the observed distribution using permutation-based methods. For a panel of 38 breast cancer cell lines, we identified a significant number of surrogate oncogenes in known oncogenes such as BRCA1 and ESR1, lending credence to this approach. In addition, using Random Forest Classifiers, we show that these significant surrogate oncogenes predict drug sensitivity for 74 drugs in the breast cancer cell lines with a mean error rate of 30.9%. Additionally, we show that surrogate oncogenes are predictive of survival in patients. The surrogate oncogene framework incorporates unique or rare mutations from a single sample, and therefore has the potential to integrate patient-unique mutations into drug sensitivity predictions, suggesting a new direction in precision medicine and drug development. Additionally, we show the prevalence of significant surrogate oncogenes in multiple cancers from The Cancer Genome Atlas, suggesting that surrogate oncogenes may be a useful genomic feature for guiding pancancer analyses and assigning therapies across many tissue

  2. Sensitive quantitative predictions of peptide-MHC binding by a 'Query by Committee' artificial neural network approach

    DEFF Research Database (Denmark)

    Buus, S; Lauemøller, S L; Worning, P

    2003-01-01

    We have generated Artificial Neural Networks (ANN) capable of performing sensitive, quantitative predictions of peptide binding to the MHC class I molecule, HLA-A*0204. We have shown that such quantitative ANN are superior to conventional classification ANN, that have been trained to predict...

  3. Women's experiences of working as a Clinical Teaching Associate teaching sensitive examinations: a qualitative study.

    Science.gov (United States)

    Fairbank, Christine; Reid, Katharine; Minzenmay, Krista

    2015-01-01

    Increasingly, professional patient programs are used for training medical students to perform pelvic examinations, yet we know little of the experiences of women who teach medical students these sensitive examination skills. To describe the experiences of women working as Clinical Teaching Associates (CTAs) teaching medical students the technical and communication skills required to perform pelvic examinations. Twelve women employed as CTAs participated in semi-structured interviews. Individual interviews were used to identify major themes in women's experiences of teaching sensitive examinations to medical students. CTAs identified unique difficulties in their work including negative attitudes from others towards their role and the unpleasantness of the examination, although other challenges (such as teamwork issues or providing negative feedback to colleagues) were characteristic of many work situations. Effective communication was identified as central to the CTA role and the women described growth in their communication skills and assertiveness that they applied to other aspects of their work and personal lives. CTAs were motivated to join the program and remained in the program because of an interest in women's health and a desire for meaningful work, which they believed improved the examination and communication skills of future doctors. Positive interactions with work colleagues were a valued part of the role and a primary motivator to remain in the program. Highlighting the experiences of women working as CTAs validates the significant teaching role these women perform and, from a pragmatic perspective, may increase understanding of the best way to attract and retain women to these important teaching roles.

  4. A position sensitive silicon detector for AEgIS (Antimatter Experiment: Gravity, Interferometry, Spectroscopy)

    CERN Multimedia

    Gligorova, A

    2014-01-01

    The AEḡIS experiment (Antimatter Experiment: Gravity, Interferometry, Spectroscopy) is located at the Antiproton Decelerator (AD) at CERN and studies antimatter. The main goal of the AEḡIS experiment is to carry out the first measurement of the gravitational acceleration for antimatter in Earth’s gravitational field to a 1% relative precision. Such a measurement would test the Weak Equivalence Principle (WEP) of Einstein’s General Relativity. The gravitational acceleration for antihydrogen will be determined using a set of gravity measurement gratings (Moiré deflectometer) and a position sensitive detector. The vertical shift due to gravity of the falling antihydrogen atoms will be detected with a silicon strip detector, where the annihilation of antihydrogen will take place. This poster presents part of the development process of this detector.

  5. Review of the VSAT acts experiments at the center for satellite & hybrid communication networks

    Science.gov (United States)

    Friedman, Daniel; Gupta, Sonjai; Zhang, Chuanguo; Ephremides, Anthony

    1996-03-01

    This paper describes experiments conducted over ACTS and the associated T1 VSAT terminal. The experiments were motivated by the commercial potential of low-cost receive-only satellite terminals that can operate in a hybrid network environment, and by the desire to demonstrate frame relay technology over satellite networks. A custom unit termed Frame Relay Access Switch (FRACS) was developed by COMSAT Laboratories for these experiments; the preparation and conduct of these experiments involved a total of twenty people from the University of Maryland, the University of Colorado, and COMSAT Laboratories, from late 1992 through 1995.

  6. Laryngeal sensitivity evaluation and dysphagia: Hospital Sírio-Libanês experience

    Directory of Open Access Journals (Sweden)

    Orlando Parise Junior

    Full Text Available CONTEXT: Laryngeal sensitivity is important in the coordination of swallowing coordination and avoidance of aspiration. OBJECTIVE: To briefly review the physiology of swallowing and report on our experience with laryngeal sensitivity evaluation among patients presenting dysphagia. TYPE OF STUDY: Prospective. SETTING: Endoscopy Department, Hospital Sírio-Libanês. METHODS: Clinical data, endoscopic findings from the larynx and the laryngeal sensitivity, as assessed via the Flexible Endoscopic Evaluation of Swallowing with Sensory Testing (FEESST protocol (using the Pentax AP4000 system, were prospectively studied. The chi-squared and Student t tests were used to compare differences, which were considered significant if p < or = 0.05. RESULTS: The study included 111 patients. A direct association was observed for hyperplasia and hyperemia of the posterior commissure region in relation to globus (p = 0.01 and regurgitation (p = 0.04. Hyperemia of the posterior commissure region had a direct association with sialorrhea (p = 0.03 and an inverse association with xerostomia (p = 0.03. There was a direct association between severe laryngeal sensitivity deficit and previous radiotherapy of the head and neck (p = 0.001. DISCUSSION: These data emphasize the association between proximal gastroesophageal reflux and chronic posterior laryngitis, and suggest that decreased laryngeal sensitivity could be a side effect of radiotherapy. CONCLUSIONS: Even considering that these results are preliminary, the endoscopic findings from laryngoscopy seem to be important in the diagnosis of proximal gastroesophageal reflux. Study of laryngeal sensitivity may have the potential for improving the knowledge and clinical management of dysphagia.

  7. Sensitivity versus accuracy in multiclass problems using memetic Pareto evolutionary neural networks.

    Science.gov (United States)

    Fernández Caballero, Juan Carlos; Martínez, Francisco José; Hervás, César; Gutiérrez, Pedro Antonio

    2010-05-01

    This paper proposes a multiclassification algorithm using multilayer perceptron neural network models. It tries to boost two conflicting main objectives of multiclassifiers: a high correct classification rate level and a high classification rate for each class. This last objective is not usually optimized in classification, but is considered here given the need to obtain high precision in each class in real problems. To solve this machine learning problem, we use a Pareto-based multiobjective optimization methodology based on a memetic evolutionary algorithm. We consider a memetic Pareto evolutionary approach based on the NSGA2 evolutionary algorithm (MPENSGA2). Once the Pareto front is built, two strategies or automatic individual selection are used: the best model in accuracy and the best model in sensitivity (extremes in the Pareto front). These methodologies are applied to solve 17 classification benchmark problems obtained from the University of California at Irvine (UCI) repository and one complex real classification problem. The models obtained show high accuracy and a high classification rate for each class.

  8. A Sensitive Secondary Users Selection Algorithm for Cognitive Radio Ad Hoc Networks

    Directory of Open Access Journals (Sweden)

    Aohan Li

    2016-03-01

    Full Text Available Secondary Users (SUs are allowed to use the temporarily unused licensed spectrum without disturbing Primary Users (PUs in Cognitive Radio Ad Hoc Networks (CRAHNs. Existing architectures for CRAHNs impose energy-consuming Cognitive Radios (CRs on SUs. However, the advanced CRs will increase energy cost for their cognitive functionalities, which is undesirable for the battery powered devices. A new architecture referred to as spectral Requirement-based CRAHN (RCRAHN is proposed to enhance energy efficiency for CRAHNs in this paper. In RCRAHNs, only parts of SUs are equipped with CRs. SUs equipped with CRs are referred to as Cognitive Radio Users (CRUs. To further enhance energy efficiency of CRAHNs, we aim to select minimum CRUs to sense available spectrum. A non-linear programming problem is mathematically formulated under the constraints of energy efficiency and real-time. Considering the NP-hardness of the problem, a framework of a heuristic algorithm referred to as Sensitive Secondary Users Selection (SSUS was designed to compute the near-optimal solutions. The simulation results demonstrate that SSUS not only improves the energy efficiency, but also achieves satisfied performances in end-to-end delay and communication reliability.

  9. Sensitivity Study on Availability of I&C Components Using Bayesian Network

    Directory of Open Access Journals (Sweden)

    Rahman Khalil Ur

    2013-01-01

    Full Text Available The objective of this study is to find out the impact of instrumentation and control (I&C components on the availability of I&C systems in terms of sensitivity analysis using Bayesian network. The analysis has been performed on I&C architecture of reactor protection system. The analysis results would be applied to develop I&C architecture which will meet the desire reliability features and save cost. RPS architecture unavailability P(x=0 and availability P(x=1 were estimated to 6.1276E-05 and 9.9994E-01 for failure (0 and perfect (1 states, respectively. The impact of I&C components on overall system risk has been studied in terms of risk achievement worth (RAW and risk reduction worth (RRW. It is found that circuit breaker failure (TCB, bi-stable processor (BP, sensor transmitter (TR, and pressure transmitter (PT have high impact on risk. The study concludes and recommends that circuit breaker bi-stable processor should be given more consideration while designing I&C architecture.

  10. A Sensitive Secondary Users Selection Algorithm for Cognitive Radio Ad Hoc Networks.

    Science.gov (United States)

    Li, Aohan; Han, Guangjie; Wan, Liangtian; Shu, Lei

    2016-03-26

    Secondary Users (SUs) are allowed to use the temporarily unused licensed spectrum without disturbing Primary Users (PUs) in Cognitive Radio Ad Hoc Networks (CRAHNs). Existing architectures for CRAHNs impose energy-consuming Cognitive Radios (CRs) on SUs. However, the advanced CRs will increase energy cost for their cognitive functionalities, which is undesirable for the battery powered devices. A new architecture referred to as spectral Requirement-based CRAHN (RCRAHN) is proposed to enhance energy efficiency for CRAHNs in this paper. In RCRAHNs, only parts of SUs are equipped with CRs. SUs equipped with CRs are referred to as Cognitive Radio Users (CRUs). To further enhance energy efficiency of CRAHNs, we aim to select minimum CRUs to sense available spectrum. A non-linear programming problem is mathematically formulated under the constraints of energy efficiency and real-time. Considering the NP-hardness of the problem, a framework of a heuristic algorithm referred to as Sensitive Secondary Users Selection (SSUS) was designed to compute the near-optimal solutions. The simulation results demonstrate that SSUS not only improves the energy efficiency, but also achieves satisfied performances in end-to-end delay and communication reliability.

  11. Sensory sensitivity, attachment experiences, and rejection responses among adults with borderline and avoidant features.

    Science.gov (United States)

    Meyer, Björn; Ajchenbrenner, Muriel; Bowles, David P

    2005-12-01

    Both avoidant and borderline personality disorder (APD and BPD) are theoretically associated with temperamental vulnerabilities, adverse attachment experiences, and negative (pessimistic or catastrophic) reactions to the threat of perceived rejection; however, more work is needed to differentiate how these processes account for the etiology and maintenance of both disorders. In this study, 156 adults completed questionnaires measuring APD and BPD features, temperament (sensory-processing sensitivity), mood, and attachment experiences. A vignette task was devised to examine pessimistic cognitive-affective reactions in situations signaling potential rejection. Both APD and BPD were associated with temperamental sensitivity, but BPD was uniquely linked with a subscale measuring sensitivity to mental and emotive stimuli, whereas APD was uniquely linked with a subscale measuring the control and avoidance of aversive stimulation. Compared to APD, BPD was more strongly linked with negative moods (anxiety, anger, sadness) and insecure attachment to parents, whereas APD was more strongly linked (than BPD) to pessimistic cognitive-affective responses to rejection-related situations.

  12. DVB-S2 Experiment over NASA's Space Network

    Science.gov (United States)

    Downey, Joseph A.; Evans, Michael A.; Tollis, Nicholas S.

    2017-01-01

    The commercial DVB-S2 standard was successfully demonstrated over NASAs Space Network (SN) and the Tracking Data and Relay Satellite System (TDRSS) during testing conducted September 20-22nd, 2016. This test was a joint effort between NASA Glenn Research Center (GRC) and Goddard Space Flight Center (GSFC) to evaluate the performance of DVB-S2 as an alternative to traditional NASA SN waveforms. Two distinct sets of tests were conducted: one was sourced from the Space Communication and Navigation (SCaN) Testbed, an external payload on the International Space Station, and the other was sourced from GRCs S-band ground station to emulate a Space Network user through TDRSS. In both cases, a commercial off-the-shelf (COTS) receiver made by Newtec was used to receive the signal at White Sands Complex. Using SCaN Testbed, peak data rates of 5.7 Mbps were demonstrated. Peak data rates of 33 Mbps were demonstrated over the GRC S-band ground station through a 10MHz channel over TDRSS, using 32-amplitude phase shift keying (APSK) and a rate 89 low density parity check (LDPC) code. Advanced features of the DVB-S2 standard were evaluated, including variable and adaptive coding and modulation (VCMACM), as well as an adaptive digital pre-distortion (DPD) algorithm. These features provided additional data throughput and increased link performance reliability. This testing has shown that commercial standards are a viable, low-cost alternative for future Space Network users.

  13. Federated software defined network operations for LHC experiments

    Science.gov (United States)

    Kim, Dongkyun; Byeon, Okhwan; Cho, Kihyeon

    2013-09-01

    The most well-known high-energy physics collaboration, the Large Hadron Collider (LHC), which is based on e-Science, has been facing several challenges presented by its extraordinary instruments in terms of the generation, distribution, and analysis of large amounts of scientific data. Currently, data distribution issues are being resolved by adopting an advanced Internet technology called software defined networking (SDN). Stability of the SDN operations and management is demanded to keep the federated LHC data distribution networks reliable. Therefore, in this paper, an SDN operation architecture based on the distributed virtual network operations center (DvNOC) is proposed to enable LHC researchers to assume full control of their own global end-to-end data dissemination. This may achieve an enhanced data delivery performance based on data traffic offloading with delay variation. The evaluation results indicate that the overall end-to-end data delivery performance can be improved over multi-domain SDN environments based on the proposed federated SDN/DvNOC operation framework.

  14. The effect of tracking network configuration on GPS baseline estimates for the CASA Uno experiment

    Science.gov (United States)

    Wolf, S. Kornreich; Dixon, T. H.; Freymueller, J. T.

    1990-01-01

    The effect of the tracking network on long (greater than 100 km) GPS baseline estimates was estimated using various subsets of the global tracking network initiated by the first Central and South America (CASA Uno) experiment. It was found that best results could be obtained with a global tacking network consisting of three U.S. stations, two sites in the southwestern Pacific, and two sites in Europe. In comparison with smaller subsets, this global network improved the baseline repeatability, the resolution of carrier phase cycle ambiguities, and formal errors of the orbit estimates.

  15. Greenhouse gas network design using backward Lagrangian particle dispersion modelling - Part 2: Sensitivity analyses and South African test case

    Science.gov (United States)

    Nickless, A.; Ziehn, T.; Rayner, P. J.; Scholes, R. J.; Engelbrecht, F.

    2015-02-01

    This is the second part of a two-part paper considering a measurement network design based on a stochastic Lagrangian particle dispersion model (LPDM) developed by Marek Uliasz, in this case for South Africa. A sensitivity analysis was performed for different specifications of the network design parameters which were applied to this South African test case. The LPDM, which can be used to derive the sensitivity matrix used in an atmospheric inversion, was run for each candidate station for the months of July (representative of the Southern Hemisphere winter) and January (summer). The network optimisation procedure was carried out under a standard set of conditions, similar to those applied to the Australian test case in Part 1, for both months and for the combined 2 months, using the incremental optimisation (IO) routine. The optimal network design setup was subtly changed, one parameter at a time, and the optimisation routine was re-run under each set of modified conditions and compared to the original optimal network design. The assessment of the similarity between network solutions showed that changing the height of the surface grid cells, including an uncertainty estimate for the ocean fluxes, or increasing the night-time observation error uncertainty did not result in any significant changes in the positioning of the stations relative to the standard design. However, changing the prior flux error covariance matrix, or increasing the spatial resolution, did. Large aggregation errors were calculated for a number of candidate measurement sites using the resolution of the standard network design. Spatial resolution of the prior fluxes should be kept as close to the resolution of the transport model as the computing system can manage, to mitigate the exclusion of sites which could potentially be beneficial to the network. Including a generic correlation structure in the prior flux error covariance matrix led to pronounced changes in the network solution. The genetic

  16. Establishing a clinical trials network in nephrology: experience of the Australasian Kidney Trials Network.

    Science.gov (United States)

    Morrish, Alicia T; Hawley, Carmel M; Johnson, David W; Badve, Sunil V; Perkovic, Vlado; Reidlinger, Donna M; Cass, Alan

    2014-01-01

    Chronic kidney disease is a major public health problem globally. Despite this, there are fewer high-quality, high-impact clinical trials in nephrology than other internal medicine specialties, which has led to large gaps in evidence. To address this deficiency, the Australasian Kidney Trials Network, a Collaborative Research Group, was formed in 2005. Since then, the Network has provided infrastructure and expertise to conduct patient-focused high-quality, investigator-initiated clinical trials in nephrology. The Network has not only been successful in engaging the nephrology community in Australia and New Zealand but also in forming collaborations with leading researchers from other countries. This article describes the establishment, development, and functions of the Network. The article also discusses the current and future funding strategies to ensure uninterrupted conduct of much needed clinical trials in nephrology to improve the outcomes of patients affected by kidney diseases with cost-effective interventions.

  17. Cooperation and contagion in web-based, networked public goods experiments.

    Directory of Open Access Journals (Sweden)

    Siddharth Suri

    Full Text Available A longstanding idea in the literature on human cooperation is that cooperation should be reinforced when conditional cooperators are more likely to interact. In the context of social networks, this idea implies that cooperation should fare better in highly clustered networks such as cliques than in networks with low clustering such as random networks. To test this hypothesis, we conducted a series of web-based experiments, in which 24 individuals played a local public goods game arranged on one of five network topologies that varied between disconnected cliques and a random regular graph. In contrast with previous theoretical work, we found that network topology had no significant effect on average contributions. This result implies either that individuals are not conditional cooperators, or else that cooperation does not benefit from positive reinforcement between connected neighbors. We then tested both of these possibilities in two subsequent series of experiments in which artificial seed players were introduced, making either full or zero contributions. First, we found that although players did generally behave like conditional cooperators, they were as likely to decrease their contributions in response to low contributing neighbors as they were to increase their contributions in response to high contributing neighbors. Second, we found that positive effects of cooperation were contagious only to direct neighbors in the network. In total we report on 113 human subjects experiments, highlighting the speed, flexibility, and cost-effectiveness of web-based experiments over those conducted in physical labs.

  18. Cooperation and contagion in web-based, networked public goods experiments.

    Science.gov (United States)

    Suri, Siddharth; Watts, Duncan J

    2011-03-11

    A longstanding idea in the literature on human cooperation is that cooperation should be reinforced when conditional cooperators are more likely to interact. In the context of social networks, this idea implies that cooperation should fare better in highly clustered networks such as cliques than in networks with low clustering such as random networks. To test this hypothesis, we conducted a series of web-based experiments, in which 24 individuals played a local public goods game arranged on one of five network topologies that varied between disconnected cliques and a random regular graph. In contrast with previous theoretical work, we found that network topology had no significant effect on average contributions. This result implies either that individuals are not conditional cooperators, or else that cooperation does not benefit from positive reinforcement between connected neighbors. We then tested both of these possibilities in two subsequent series of experiments in which artificial seed players were introduced, making either full or zero contributions. First, we found that although players did generally behave like conditional cooperators, they were as likely to decrease their contributions in response to low contributing neighbors as they were to increase their contributions in response to high contributing neighbors. Second, we found that positive effects of cooperation were contagious only to direct neighbors in the network. In total we report on 113 human subjects experiments, highlighting the speed, flexibility, and cost-effectiveness of web-based experiments over those conducted in physical labs.

  19. Grid Sensitivity Test for STERN Experiment by using the CUPID Code

    Energy Technology Data Exchange (ETDEWEB)

    Park, Sang Gi; Jeong, Jae Jun [Pusan National Univ., Busan (Korea, Republic of); Lee, Jae Ryong; Yoon, Han Young [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2013-10-15

    In order to predict the local temperature, the extensive experiments and calculations have been conducted. In previous study, the CUPID code was validated against the STERN experiment using a two-dimensional grid. In this study, the previous two-dimensional analysis was extended to a three-dimensional analysis and, thus, a grid sensitivity calculation was performed. The three-dimensional grid was based on the two dimensional grid. The nominal case of experiment performed at STERN Laboratories Inc. was used in this calculation. The applicability of the CUPID code to the CANDU moderator system analysis has been evaluated. In this study, the empirical pressure drop model for a porous media was implemented into the CUPID code first for a three-dimensional analysis. Then, three-dimensional grid sensitivity tests were performed, which is based on the previous two-dimensional analysis. It was shown that the maximum temperature is getting lower as decreasing the number of total grids. As a result, the three-dimensional grid of 7000 meshes in the cross section and 5 layers in the axial direction is proper.

  20. Some Psychoacoustical Experiments with All-Pass Networks.

    Science.gov (United States)

    Hartmann, W. M.

    1979-01-01

    All-pass filter systems can be used in laboratory experiments in the physics and psychophysics of sound and music. Particular applications, such as lateralization of sounds in headphone listening, are presented. (BB)

  1. Functional Integration between Salience and Central Executive Networks: A Role for Action Video Game Experience.

    Science.gov (United States)

    Gong, Diankun; He, Hui; Ma, Weiyi; Liu, Dongbo; Huang, Mengting; Dong, Li; Gong, Jinnan; Li, Jianfu; Luo, Cheng; Yao, Dezhong

    2016-01-01

    Action video games (AVGs) have attracted increasing research attention as they offer a unique perspective into the relation between active learning and neural plasticity. However, little research has examined the relation between AVG experience and the plasticity of neural network mechanisms. It has been proposed that AVG experience is related to the integration between Salience Network (SN) and Central Executive Network (CEN), which are responsible for attention and working memory, respectively, two cognitive functions essential for AVG playing. This study initiated a systematic investigation of this proposition by analyzing AVG experts' and amateurs' resting-state brain functions through graph theoretical analyses and functional connectivity. Results reveal enhanced intra- and internetwork functional integrations in AVG experts compared to amateurs. The findings support the possible relation between AVG experience and the neural network plasticity.

  2. Functional Integration between Salience and Central Executive Networks: A Role for Action Video Game Experience

    Directory of Open Access Journals (Sweden)

    Diankun Gong

    2016-01-01

    Full Text Available Action video games (AVGs have attracted increasing research attention as they offer a unique perspective into the relation between active learning and neural plasticity. However, little research has examined the relation between AVG experience and the plasticity of neural network mechanisms. It has been proposed that AVG experience is related to the integration between Salience Network (SN and Central Executive Network (CEN, which are responsible for attention and working memory, respectively, two cognitive functions essential for AVG playing. This study initiated a systematic investigation of this proposition by analyzing AVG experts’ and amateurs’ resting-state brain functions through graph theoretical analyses and functional connectivity. Results reveal enhanced intra- and internetwork functional integrations in AVG experts compared to amateurs. The findings support the possible relation between AVG experience and the neural network plasticity.

  3. Numerical modeling and sensitivity analysis of seawater intrusion in a dual-permeability coastal karst aquifer with conduit networks

    Directory of Open Access Journals (Sweden)

    Z. Xu

    2018-01-01

    Full Text Available Long-distance seawater intrusion has been widely observed through the subsurface conduit system in coastal karst aquifers as a source of groundwater contaminant. In this study, seawater intrusion in a dual-permeability karst aquifer with conduit networks is studied by the two-dimensional density-dependent flow and transport SEAWAT model. Local and global sensitivity analyses are used to evaluate the impacts of boundary conditions and hydrological characteristics on modeling seawater intrusion in a karst aquifer, including hydraulic conductivity, effective porosity, specific storage, and dispersivity of the conduit network and of the porous medium. The local sensitivity analysis evaluates the parameters' sensitivities for modeling seawater intrusion, specifically in the Woodville Karst Plain (WKP. A more comprehensive interpretation of parameter sensitivities, including the nonlinear relationship between simulations and parameters, and/or parameter interactions, is addressed in the global sensitivity analysis. The conduit parameters and boundary conditions are important to the simulations in the porous medium because of the dynamical exchanges between the two systems. The sensitivity study indicates that salinity and head simulations in the karst features, such as the conduit system and submarine springs, are critical for understanding seawater intrusion in a coastal karst aquifer. The evaluation of hydraulic conductivity sensitivity in the continuum SEAWAT model may be biased since the conduit flow velocity is not accurately calculated by Darcy's equation as a function of head difference and hydraulic conductivity. In addition, dispersivity is no longer an important parameter in an advection-dominated karst aquifer with a conduit system, compared to the sensitivity results in a porous medium aquifer. In the end, the extents of seawater intrusion are quantitatively evaluated and measured under different scenarios with the variabilities of

  4. Numerical modeling and sensitivity analysis of seawater intrusion in a dual-permeability coastal karst aquifer with conduit networks

    Science.gov (United States)

    Xu, Zexuan; Hu, Bill X.; Ye, Ming

    2018-01-01

    Long-distance seawater intrusion has been widely observed through the subsurface conduit system in coastal karst aquifers as a source of groundwater contaminant. In this study, seawater intrusion in a dual-permeability karst aquifer with conduit networks is studied by the two-dimensional density-dependent flow and transport SEAWAT model. Local and global sensitivity analyses are used to evaluate the impacts of boundary conditions and hydrological characteristics on modeling seawater intrusion in a karst aquifer, including hydraulic conductivity, effective porosity, specific storage, and dispersivity of the conduit network and of the porous medium. The local sensitivity analysis evaluates the parameters' sensitivities for modeling seawater intrusion, specifically in the Woodville Karst Plain (WKP). A more comprehensive interpretation of parameter sensitivities, including the nonlinear relationship between simulations and parameters, and/or parameter interactions, is addressed in the global sensitivity analysis. The conduit parameters and boundary conditions are important to the simulations in the porous medium because of the dynamical exchanges between the two systems. The sensitivity study indicates that salinity and head simulations in the karst features, such as the conduit system and submarine springs, are critical for understanding seawater intrusion in a coastal karst aquifer. The evaluation of hydraulic conductivity sensitivity in the continuum SEAWAT model may be biased since the conduit flow velocity is not accurately calculated by Darcy's equation as a function of head difference and hydraulic conductivity. In addition, dispersivity is no longer an important parameter in an advection-dominated karst aquifer with a conduit system, compared to the sensitivity results in a porous medium aquifer. In the end, the extents of seawater intrusion are quantitatively evaluated and measured under different scenarios with the variabilities of important parameters

  5. Aerobrake heating rate sensitivity study for the Aeroassist Flight Experiment (AFE)

    Science.gov (United States)

    Rochelle, W. C.; Ting, P. C.; Mueller, S. R.; Colovin, J. E.; Bouslog, S. A.; Curry, D. M.; Scott, C. D.

    1989-01-01

    The sensitivities associated with the prediction of the Aeroassist Flight Experiment (AFE) vehicle's aerothermodynamic environment are presently evaluated in order to assess the heating-rate uncertainties of the AFE's aerobrake component, as a function of time in various trajectories, and as a function of distance around the aerobrake. Relative importance is evaluated by means of the Boundary Layer Integral Matrix Procedure for such areas of uncertainty as the trajectory parameters, the catalycity of the thermal-protection tiles, the nose radius variation/surface pressure distribution, and viscous interaction effects.

  6. Designing experiments to understand the variability in biochemical reaction networks.

    Science.gov (United States)

    Ruess, Jakob; Milias-Argeitis, Andreas; Lygeros, John

    2013-11-06

    Exploiting the information provided by the molecular noise of a biological process has proved to be valuable in extracting knowledge about the underlying kinetic parameters and sources of variability from single-cell measurements. However, quantifying this additional information a priori, to decide whether a single-cell experiment might be beneficial, is currently only possible in systems where either the chemical master equation is computationally tractable or a Gaussian approximation is appropriate. Here, we provide formulae for computing the information provided by measured means and variances from the first four moments and the parameter derivatives of the first two moments of the underlying process. For stochastic kinetic models for which these moments can be either computed exactly or approximated efficiently, the derived formulae can be used to approximate the information provided by single-cell distribution experiments. Based on this result, we propose an optimal experimental design framework which we employ to compare the utility of dual-reporter and perturbation experiments for quantifying the different noise sources in a simple model of gene expression. Subsequently, we compare the information content of a set of experiments which have been performed in an engineered light-switch gene expression system in yeast and show that well-chosen gene induction patterns may allow one to identify features of the system which remain hidden in unplanned experiments.

  7. Sexual experience sensitizes mating-related nucleus accumbens dopamine responses of female Syrian hamsters.

    Science.gov (United States)

    Kohlert, J G; Meisel, R L

    1999-02-15

    We examined the effects of prior sexual experience on extracellular concentrations of dopamine in the nucleus accumbens of female hamsters. Nucleus accumbens dopamine was measured by in vivo microdialysis during mating in female Syrian hamsters that had previously been given six prior sexual encounters with a male, three prior encounters, or were sexually naive. High levels of sexual behavior were observed in all three groups, which were accompanied by increases in dialysate dopamine during periods when the male was present. However, females that received six prior sexual encounters had significantly elevated and prolonged increases in dialysate dopamine compared with those of the sexually naive females or females with only three prior sexual encounters with a male. The data indicate that the mesolimbic system can be sensitized by repeated experiences associated with a motivated behavior.

  8. Transparent TiO2 nanowire networks via wet corrosion of Ti thin films for dye-sensitized solar cells

    Science.gov (United States)

    Shin, Eunhye; Jin, Saera; Hong, Jongin

    2017-09-01

    Transparent TiO2 nanowire networks were prepared by corrosion of Ti thin films on F-doped SnO2 glass substrates in an alkaline (potassium hydroxide: KOH) solution. The formation of the porous TiO2 nanostructures from the Ti thin films was thoroughly investigated. Dye-sensitized solar cells with a photoanode of 1.2-μm-thick nanowire networks exhibit an average optical transmittance of 40% in the visible light region and a power conversion efficiency of 1.0% under one sun illumination.

  9. Geostationary Coastal and Air Pollution Events (GEO-CAPE) Sensitivity Analysis Experiment

    Science.gov (United States)

    Lee, Meemong; Bowman, Kevin

    2014-01-01

    Geostationary Coastal and Air pollution Events (GEO-CAPE) is a NASA decadal survey mission to be designed to provide surface reflectance at high spectral, spatial, and temporal resolutions from a geostationary orbit necessary for studying regional-scale air quality issues and their impact on global atmospheric composition processes. GEO-CAPE's Atmospheric Science Questions explore the influence of both gases and particles on air quality, atmospheric composition, and climate. The objective of the GEO-CAPE Observing System Simulation Experiment (OSSE) is to analyze the sensitivity of ozone to the global and regional NOx emissions and improve the science impact of GEO-CAPE with respect to the global air quality. The GEO-CAPE OSSE team at Jet propulsion Laboratory has developed a comprehensive OSSE framework that can perform adjoint-sensitivity analysis for a wide range of observation scenarios and measurement qualities. This report discusses the OSSE framework and presents the sensitivity analysis results obtained from the GEO-CAPE OSSE framework for seven observation scenarios and three instrument systems.

  10. Femtosecond laser fabricated all-optical fiber sensors with ultrahigh refractive index sensitivity: modeling and experiment

    Science.gov (United States)

    Jiang, Lan; Zhao, Longjiang; Wang, Sumei; Yang, Jinpeng; Xiao, Hai

    2011-08-01

    All-optical fiber sensors based on ultracompact fiber inline Mach-Zehnder interferometer (MZI) are fabricated by side-ablating a U-shape microcavity in a single-mode optical fiber with the fiber core partially removed using femtosecond (fs) laser pulses, in which the two light paths are accordingly formed in the remaining D-type fiber core and the U-shape microcavity. Beam propagation method (BPM) analysis is utilized to illustrate the dependences of good transmission spectra on parameters including the ablation depth, ablation length and the refractive index of U-shape micocavity, which gives some guidelines to optimize parameters for fs laser micromachining and predicts RI (refractive index) sensitivities within given RI ranges. The modeling results of ultrahigh RI sensitivities for gases and solutions are -3243.75 ± 0.65nm/RIU (refractive index unit) and -10789.29 ± 18.91nm/RIU, respectively. In RI testing experiments, the sensor exhibits ultrahigh RI sensitivities of -3754.79 ± 44.24nm/RIU with refractive indices ranging from 1.0001143 to 1.0002187 by testing different mixture ratios of N2 and He gases, and -12162.01 ± 173.92nm/RIU with refractive indices ranging from 1.3330 to 1.33801 by testing different concentrations of sucrose solutions, which is essentially in agreement with the modeling results.

  11. A common control group - optimising the experiment design to maximise sensitivity.

    Directory of Open Access Journals (Sweden)

    Simon Bate

    Full Text Available Methods for choosing an appropriate sample size in animal experiments have received much attention in the statistical and biological literature. Due to ethical constraints the number of animals used is always reduced where possible. However, as the number of animals decreases so the risk of obtaining inconclusive results increases. By using a more efficient experimental design we can, for a given number of animals, reduce this risk. In this paper two popular cases are considered, where planned comparisons are made to compare treatments back to control and when researchers plan to make all pairwise comparisons. By using theoretical and empirical techniques we show that for studies where all pairwise comparisons are made the traditional balanced design, as suggested in the literature, maximises sensitivity. For studies that involve planned comparisons of the treatment groups back to the control group, which are inherently more sensitive due to the reduced multiple testing burden, the sensitivity is maximised by increasing the number of animals in the control group while decreasing the number in the treated groups.

  12. Mass hierarchy sensitivity of medium baseline reactor neutrino experiments with multiple detectors

    Directory of Open Access Journals (Sweden)

    Hong-Xin Wang

    2017-05-01

    Full Text Available We report the neutrino mass hierarchy (MH determination of medium baseline reactor neutrino experiments with multiple detectors, where the sensitivity of measuring the MH can be significantly improved by adding a near detector. Then the impact of the baseline and target mass of the near detector on the combined MH sensitivity has been studied thoroughly. The optimal selections of the baseline and target mass of the near detector are ∼12.5 km and ∼4 kton respectively for a far detector with the target mass of 20 kton and the baseline of 52.5 km. As typical examples of future medium baseline reactor neutrino experiments, the optimal location and target mass of the near detector are selected for the specific configurations of JUNO and RENO-50. Finally, we discuss distinct effects of the reactor antineutrino energy spectrum uncertainty for setups of a single detector and double detectors, which indicate that the spectrum uncertainty can be well constrained in the presence of the near detector.

  13. A design of experiments approach for sensitivity screening of mesoscale simulations of explosive impact

    Science.gov (United States)

    Butler, George; Cox, John; Daily, Teresa; Gonthier, Keith

    2013-06-01

    This paper discusses a Design of Experiments (DOE) approach for planning inert mesoscale simulations to establish how microstructure and composition affect the uniaxial impact sensitivity of metalized Plastic Bonded Explosives (PBXs). Simulations are performed using an explicit, 2D, cohesive finite and discrete element code (CODEX), developed at Georgia Institute of Technology, and account for nonlinear deformation and fracture of PBXs: explosive crystals (HMX) and aluminum particles (Al) in a polymeric binder. The relative sensitivity of PBX formulations is established by critical hot-spots formed in the microstructure. The code has flexibility in prescribing material properties, but this initial screening examines five independent variables: impact speed, initial size of HMX crystals and Al particles, and initial volume fractions of HMX and Al (the binder ensures saturation). Input settings are prescribed by the DOE approach, which plans the experiments to ensure an ability to reach statistically valid, objective conclusions with minimal runs. A full factorial matrix of simulations requires 296 runs, and each run takes up to a week. DOE reduced the matrix to 101 runs, while retaining the ability to estimate dominant variable effects and the effect of variable interactions on hot spot formation. These analyses provide a qualitative validation of CODEX, and a framework for subsequent simulations. DISTRIBUTION A. Approved for public release, distribution unlimited. (96ABW-2013-0054)

  14. A pure shift experiment with increased sensitivity and superior performance for strongly coupled systems.

    Science.gov (United States)

    Ilgen, Julian; Kaltschnee, Lukas; Thiele, Christina M

    2017-11-06

    Motivated by the persisting need for enhanced resolution in solution state NMR spectra, pure shift techniques such as Zangger-Sterk decoupling have recently attracted widespread interest. These techniques for homonuclear decoupling offer enhanced resolution in one- and multidimensional proton detected experiments by simplifying multiplet structures. In this work, a modification to the popular Zangger-Sterk technique PEPSIE (Perfect Echo Pure Shift Improved Experiment) is presented, which decouples pairs of spins even if they share the same volume element. This in turn can drastically improve the sensitivity, as compared to classical Zangger-Sterk decoupling, as larger volume elements can be used to collect the detected signal. Most interestingly, even in the presence of moderate strong coupling, the PEPSIE experiment produces clean and widely artifact free spectra. In order to better understand this - to us initially - surprising behaviour we performed analyses using numerical simulations and derived an (approximate) analytical solution from density matrix formalism. We show that this experiment is particularly suitable to study samples with strong signal clustering, a situation which can render classic Zangger-Sterk decoupling inefficient. Copyright © 2017 Elsevier Inc. All rights reserved.

  15. The many facets of integrating data and metadata for research networks: experience from the AmeriFlux Network

    Science.gov (United States)

    Pastorello, G.; Poindexter, C.; van Ingen, C.; Papale, D.; Agarwal, D.

    2014-12-01

    Grassroots research networks, such as AmeriFlux, require data and metadata integration from multiple, independently managed field sites, scales, and science domains. The goal of these networks is production of consistent datasets enabling investigation of broad science questions at regional and global scales. These datasets combine data from a large number of data providers, who often utilize different data collection protocols and data processing approaches. In this scenario, data integration and curation quickly become large-scale efforts. This presentation reports on our experience with integration efforts for the AmeriFlux network. In AmeriFlux we are attempting to integrate flux, meteorological, biological, soil, chemistry, and disturbance data and metadata. Our data management activities range from acquisition/publication mechanisms, quality control, processing and product generation, data and software synchronized versioning and archiving, and interaction mechanisms and tools for data providers and data users. To enable consistent data processing and network-level data quality, combinations of automated and visual data quality assessment procedures were built, extending on checks already done at site levels. The implementation of community developed and trusted algorithms to operate in production mode proved to be a key aspect of data product generation, with extensive testing and validation being one of the main concerns. Clear definitions for data processing levels help with easily tracking different data products and data quality levels. For metadata and ancillary information, formatting standards are even more relevant, since variables collected are considerably more heterogeneous. Documentation and training on the standards were crucial in this case, with instruction sessions having proved to be an effective approach, given that documentation cannot cover all different scenarios at different sites. This work is being developed in close coordination with

  16. Assessing model sensitivity and uncertainty across multiple Free-Air CO2 Enrichment experiments.

    Science.gov (United States)

    Cowdery, E.; Dietze, M.

    2015-12-01

    As atmospheric levels of carbon dioxide levels continue to increase, it is critical that terrestrial ecosystem models can accurately predict ecological responses to the changing environment. Current predictions of net primary productivity (NPP) in response to elevated atmospheric CO2 concentrations are highly variable and contain a considerable amount of uncertainty. It is necessary that we understand which factors are driving this uncertainty. The Free-Air CO2 Enrichment (FACE) experiments have equipped us with a rich data source that can be used to calibrate and validate these model predictions. To identify and evaluate the assumptions causing inter-model differences we performed model sensitivity and uncertainty analysis across ambient and elevated CO2 treatments using the Data Assimilation Linked Ecosystem Carbon (DALEC) model and the Ecosystem Demography Model (ED2), two process-based models ranging from low to high complexity respectively. These modeled process responses were compared to experimental data from the Kennedy Space Center Open Top Chamber Experiment, the Nevada Desert Free Air CO2 Enrichment Facility, the Rhinelander FACE experiment, the Wyoming Prairie Heating and CO2 Enrichment Experiment, the Duke Forest Face experiment and the Oak Ridge Experiment on CO2 Enrichment. By leveraging data access proxy and data tilling services provided by the BrownDog data curation project alongside analysis modules available in the Predictive Ecosystem Analyzer (PEcAn), we produced automated, repeatable benchmarking workflows that are generalized to incorporate different sites and ecological models. Combining the observed patterns of uncertainty between the two models with results of the recent FACE-model data synthesis project (FACE-MDS) can help identify which processes need further study and additional data constraints. These findings can be used to inform future experimental design and in turn can provide informative starting point for data assimilation.

  17. Integrated monitoring of multi-domain backbone connections Operational experience in the LHC optical private network

    CERN Document Server

    Marcu, Patricia; Fritz, Wolfgang; Yampolskiy, Mark; Hommel, Wolfgang

    2011-01-01

    Novel large scale research projects often require cooperation between various different project partners that are spread among the entire world. They do not only need huge computing resources, but also a reliable network to operate on. The Large Hadron Collider (LHC) at CERN is a representative example for such a project. Its experiments result in a vast amount of data, which is interesting for researchers around the world. For transporting the data from CERN to 11 data processing and storage sites, an optical private network (OPN) has been constructed. As the experiment data is highly valuable, LHC defines very high requirements to the underlying network infrastructure. In order to fulfil those requirements, the connections have to be managed and monitored permanently. In this paper, we present the integrated monitoring solution developed for the LHCOPN. We first outline the requirements and show how they are met on the single network layers. After that, we describe, how those single measurements can be comb...

  18. Sensitivity Experiments on the Impact of Vb-Cyclones to Ocean Temperature and Soil Moisture Changes

    Science.gov (United States)

    Messmer, Martina; José Gómez-Navarro, Juan; Raible, Christoph C.

    2016-04-01

    Cyclones developing over the western Mediterranean and move northeastward are a major source of extreme weather and responsible for heavy precipitation over Central Europe. Gaining insight into these processes is crucial to improve the projection of changes in frequency and severity of these so-called Vb-cyclones under future climate change scenarios. This study explores the impact of climate change on Vb-events through a number of idealized sensitivity experiments that assess the role of the sea surface temperature (SST) and soil moisture and their contribution to the moisture content in the atmosphere in recent Vb-events. To achieve this task, we use the Weather Research and Forecasting model (WRF) to dynamically downscale the ERA Interim reanalysis, simulating five prominent Vb-events that led to extreme precipitation in Central Europe. WRF allows simulating a physical consistent response of Vb-cyclones to different SSTs and soil water volumes. The changes in SSTs are designed to follow the expected temperature changes in a future climate scenario. Additionally the corresponding uncertainty in such projections is considered. Results indicate that although an increase of the Mediterranean SSTs leads to increased precipitation over Central Europe, e.g. 136% greater precipitation in the +5 K experiment compared to the control simulation, a change in the high-impact region of Vb-events at the northern side of the Alps is not found. This counter-intuitive behavior seems to be related to the increase of atmospheric instability over the artificially heated SSTs. Thereby, precipitation notably increases over the east Adriatic coast in response to warmer SSTs, which corresponds to the first location where the air is lifted. However, Vb-events become less destructive in their high-impact region, due to high loss of atmospheric water. Further experiments demonstrate that changing the SSTs of the Atlantic invokes almost no reaction (around 1% change) with respect to

  19. Dynamic Control of Adsorption Sensitivity for Photo-EMF-Based Ammonia Gas Sensors Using a Wireless Network

    OpenAIRE

    Yuriy Vashpanov; Hyunseung Choo; Dongsoo Stephen Kim

    2011-01-01

    This paper proposes an adsorption sensitivity control method that uses a wireless network and illumination light intensity in a photo-electromagnetic field (EMF)-based gas sensor for measurements in real time of a wide range of ammonia concentrations. The minimum measurement error for a range of ammonia concentration from 3 to 800 ppm occurs when the gas concentration magnitude corresponds with the optimal intensity of the illumination light. A simulation with LabView-engineered modules for a...

  20. TiO2 Nanowire Networks Prepared by Titanium Corrosion and Their Application to Bendable Dye-Sensitized Solar Cells

    Directory of Open Access Journals (Sweden)

    Saera Jin

    2017-10-01

    Full Text Available TiO2 nanowire networks were prepared, using the corrosion of Ti foils in alkaline (potassium hydroxide, KOH solution at different temperatures, and then a further ion-exchange process. The prepared nanostructures were characterized by field emission scanning electron microscopy, Raman spectroscopy, and X-ray photoelectron spectroscopy. The wet corroded foils were utilized as the photoanodes of bendable dye-sensitized solar cells (DSSCs, which exhibited a power conversion efficiency of 1.11% under back illumination.

  1. Note: Design and development of wireless controlled aerosol sampling network for large scale aerosol dispersion experiments

    Science.gov (United States)

    Gopalakrishnan, V.; Subramanian, V.; Baskaran, R.; Venkatraman, B.

    2015-07-01

    Wireless based custom built aerosol sampling network is designed, developed, and implemented for environmental aerosol sampling. These aerosol sampling systems are used in field measurement campaign, in which sodium aerosol dispersion experiments have been conducted as a part of environmental impact studies related to sodium cooled fast reactor. The sampling network contains 40 aerosol sampling units and each contains custom built sampling head and the wireless control networking designed with Programmable System on Chip (PSoC™) and Xbee Pro RF modules. The base station control is designed using graphical programming language LabView. The sampling network is programmed to operate in a preset time and the running status of the samplers in the network is visualized from the base station. The system is developed in such a way that it can be used for any other environment sampling system deployed in wide area and uneven terrain where manual operation is difficult due to the requirement of simultaneous operation and status logging.

  2. An analysis of network reciprocity in Prisoner's Dilemma games using Full Factorial Designs of Experiment.

    Science.gov (United States)

    Yamauchi, Atsuo; Tanimoto, Jun; Hagishima, Aya

    2011-01-01

    Despite hundreds of studies on the Prisoner's Dilemma (PD) game, understanding about network reciprocity remains a unsolved puzzle. Thus, we performed a series of Full Factorial Design of Experiments (FFDOE) to evaluate what dominates emerging cooperation in the PD game on various networks. The results qualitatively reveal the influence of each factor and show that some combinations of factors have complicated interactions. Remarkably, the choice of strategy update rule or update dynamics is much more important than the type of network imposed or, at least, the factorial effect of the average degree of the network reported by Nowak (Science 314, 5805, 1560-1563, 2006) and Ohtsuki et al. (Nature 441, 502-505, 2006). Furthermore, the decision of which PD game type to investigate (whether all PD games, PD-Chicken boundary games or Donor & Recipient games) is important for discussing network reciprocity. Copyright © 2010 Elsevier Ireland Ltd. All rights reserved.

  3. Tie Strength, Embeddedness, and Social Influence: A Large-Scale Networked Experiment

    OpenAIRE

    Walker, Dylan; Aral, Sinan Kayhan

    2012-01-01

    We leverage the newly emerging business analytical capability to rapidly deploy and iterate large-scale, microlevel, in vivo randomized experiments to understand how social influence in networks impacts consumer demand. Understanding peer influence is critical to estimating product demand and diffusion, creating effective viral marketing, and designing “network interventions” to promote positive social change. But several statistical challenges make it difficult to econometrically identify pe...

  4. Public participation in the implementation of the Natura 2000 network in Italy: the stakeholders’ experiences

    OpenAIRE

    Paletto A.; Graziani A; Brescancin F; De_Meo I

    2017-01-01

    Public participation in the implementation of the Natura 2000 network in Italy: the stakeholders’ experiences. Natura 2000 is an ecological network of protected areas identified by the Habitats Directive (92/43/EEC) and the Birds Directive (79/409/EC) - recently replaced by the Directive 2009/147/EC - in order to ensure the long-term protection of endangered species in their natural habitats in European Union (EU) territory. EU Member States are responsible for developing and implementing the...

  5. Use of Data Denial Experiments to Evaluate ESA Forecast Sensitivity Patterns

    Energy Technology Data Exchange (ETDEWEB)

    Zack, J; Natenberg, E J; Knowe, G V; Manobianco, J; Waight, K; Hanley, D; Kamath, C

    2011-09-13

    wind speed and vertical temperature difference. Ideally, the data assimilation scheme used in the experiments would have been based upon an ensemble Kalman filter (EnKF) that was similar to the ESA method used to diagnose the Mid-Colombia Basin sensitivity patterns in the previous studies. However, the use of an EnKF system at high resolution is impractical because of the very high computational cost. Thus, it was decided to use the three-dimensional variational analysis data assimilation that is less computationally intensive and more economically practical for generating operational forecasts. There are two tasks in the current project effort designed to validate the ESA observational system deployment approach in order to move closer to the overall goal: (1) Perform an Observing System Experiment (OSE) using a data denial approach which is the focus of this task and report; and (2) Conduct a set of Observing System Simulation Experiments (OSSE) for the Mid-Colombia basin region. The results of this task are presented in a separate report. The objective of the OSE task involves validating the ESA-MOOA results from the previous sensitivity studies for the Mid-Columbia Basin by testing the impact of existing meteorological tower measurements on the 0- to 6-hour ahead 80-m wind forecasts at the target locations. The testing of the ESA-MOOA method used a combination of data assimilation techniques and data denial experiments to accomplish the task objective.

  6. The co-evolution of networks and prisoner’s dilemma game by considering sensitivity and visibility

    Science.gov (United States)

    Li, Dandan; Ma, Jing; Han, Dun; Sun, Mei; Tian, Lixin; Stanley, H. Eugene

    2017-03-01

    Strategies adopted by individuals in a social network significantly impact the network, and they strongly affect relationships between individuals in the network. Links between individuals also heavily influence their levels of cooperation. Taking into account the evolution of each individual’s connection, we explore how sensitivity and visibility affect the prisoner’s dilemma game. The so-called ‘sensitivity’ and ‘visibility’ respectively present one’s self-protection consciousness and the ability of gaining information. We find that at moderate levels of player sensitivity cooperative behavior increases, but that at high levels it is inhibited. We also find that the heterogeneity of the weight of individuals at the end of the game is higher when sensitivity and visibility are increased, but that the successful-defection-payoff has less impact on the weight of individuals and on the relationship between the heterogeneity of the weight of individuals and the density of cooperators. This framework can be used to clarify the interaction mechanism between the micro-level of individual behavior and the macro-level of individual co-evolutionary processes.

  7. Synchronously Tailoring Strain Sensitivity and Electrical Stability of Silicone Elastomer Composites by the Synergistic Effect of a Dual Conductive Network

    Directory of Open Access Journals (Sweden)

    Nanying Ning

    2016-03-01

    Full Text Available The use of conductive polymer composites (CPCs as strain sensors has been widely investigated. A wide range of strain sensitivities and high repeatability are vital for different applications of CPCs. In this study, the relations of the conductive filler network and the strain-sensing behavior and electrical stability under fatigue cycles were studied systematically for the first time based on the conductive polymethylvinylsiloxane (PMVS composites filled with both carbon nanotubes arrays (CNTAs and carbon black (CB. It was proved that the composites could be fabricated with large strain-sensing capability and a wide range of strain sensitivities by controlling the volume ratio of CNTA/CB and their amounts. Additionally, the CNTA/CB/PMVS composite with 3 vol % content of fillers showed high sensitivity (GF is 10 at 60% strain, high repeatability (the relative standard deviation (RSD of the max R/R0 value is 3.58%, and electrical stability under fatigue cycles (value range of R/R0 is 1.62 to 1.82 at the same time due to the synergistic effects of the dual conductive network of CNTAs and CB. This could not be achieved by relying on a single CNTA or CB conductive network. This study may provide guidance for the preparation of high performance CPCs for applications in strain sensors.

  8. Evaluation of pH-sensitivity and drug release characteristics of (polyacrylamide-grafted-xanthan)-carboxymethyl cellulose-based pH-sensitive interpenetrating network hydrogel beads.

    Science.gov (United States)

    Kulkarni, Raghavendra V; Sa, Biswanath

    2008-12-01

    Novel pH-sensitive interpenetrating network hydrogel beads of polyacrylamide-grafted-xanthan (PAAm-g-XG) and sodium carboxymethyl cellulose (NaCMC) loaded with ketoprofen were prepared and evaluated for pH sensitivity and drug release characteristics. The pH-sensitive PAAm-g-XG copolymer was synthesized by free radical polymerization under the nitrogen atmosphere followed by alkaline hydrolysis. The grafting and alkaline hydrolysis reactions were confirmed by Fourier transform infrared spectroscopy. Differential scanning calorimetry and X-ray diffraction studies were carried out to know the crystalline nature of encapsulated drug. Scanning electron microscopic study revealed that the interpenetrating polymer network (IPN) beads possess porous matrix structure in alkaline pH whereas nonporous matrix structure was observed in acidic pH. The swelling of the beads and drug release was significantly increased when pH of the medium was changed from acidic to alkaline. The results of pulsatile swelling study indicated that the IPN beads changed their swelling behavior when pH of the external medium was altered. As pH of the medium was changed from 1.2 to 7.4, a considerable increase in swelling was observed for all the beads. However, swelling process was slower than the deswelling. At higher pH values, the carboxyl functional groups of hydrogels undergo ionization and the osmotic pressure inside the beads increases resulting in higher swelling. Drug release followed case II transport mechanism in acidic medium whereas anomalous/non-Fickian transport mechanism was observed in alkaline medium.

  9. Pain experiences of patients with musculoskeletal pain + central sensitization: A comparative Group Delphi Study.

    Science.gov (United States)

    Schäfer, Axel Georg Meender; Joos, Leonie Johanna; Roggemann, Katharina; Waldvogel-Röcker, Kerstin; Pfingsten, Michael; Petzke, Frank

    2017-01-01

    Central sensitization (CS) is regarded as an important contributing factor for chronification of musculoskeletal pain (MSP). It is crucial to identify CS, as targeted multimodal treatment may be indicated. The primary objective of this study was therefore to explore pain experience of individuals with MSP+CS in order to gain a better understanding of symptoms in relation to CS from a patient perspective. The secondary objective was to investigate whether pain experiences of patients with MSP+CS differ from those of individuals with neuropathic pain (NP). We conducted a comparative Group Delphi Study including patients with MSP+CS and neuropathic pain (NP). 13 guiding questions were used to gather information about sensory discriminatory, affective and associated bodily, mental and emotional phenomena related to the pain experience of patients. Descriptions were categorized using qualitative content analysis. Additionally, patients completed several pain related questionnaires. Nine participants with MSP+CS and nine participants with NP participated. The Delphi procedure revealed three main themes: psycho-emotional factors, bodily factors and environmental factors. Descriptions of patients with MSP+CS showed a complex picture, psycho-emotional factors seem to have a considerable impact on pain provocation, aggravation and relief. Impairments associated with mental ability and psyche affected many aspects of daily life. In contrast, descriptions of patients with NP revealed a rather mechanistic and bodily oriented pain experience. Patients with MSP+CS reported distinct features in relation to their pain that were not captured with current questionnaires. Insight in patient's pain experience may help to choose and develop appropriate diagnostic instruments.

  10. Collaborative community research dissemination and networking: Experiences and challenges

    Directory of Open Access Journals (Sweden)

    Hannah Macpherson

    2017-06-01

    Full Text Available This article reports on the experiences of a community-university research partnership with young people’s arts organisations that disseminated their collaborative work on resilience at a Research Showcase event held in Cardiff in June 2014. Through interviews with the young people and their collaborators, and critical reflection on our collective experiences, this article identifies some of the challenges and logistical issues that were encountered in the planning and implementation of the creative ‘Resilience House’ exhibit. We argue that the not often discussed nitty-gritty of this work needs to be brought to the foreground to help make collaborative research meaningfully inclusive if ideals of ‘cross-connection’ and a ‘new public knowledge landscape’ are to be realised. For example, we identify the potential developmental benefits to young people (rather simply framed as ‘participants’ of being involved in research dissemination, but that factoring in time, shaping expectations of all contributors, training contributors to speak to the public about their work, ensuring appropriate sub-forums are constructed and attended, discussing different cultures of language and ensuring basic needs are met are key foundations that need to be built on in future collaborative dissemination activity.

  11. Selective adaptation in networks of heterogeneous populations: model, simulation, and experiment.

    Directory of Open Access Journals (Sweden)

    Avner Wallach

    2008-02-01

    Full Text Available Biological systems often change their responsiveness when subject to persistent stimulation, a phenomenon termed adaptation. In neural systems, this process is often selective, allowing the system to adapt to one stimulus while preserving its sensitivity to another. In some studies, it has been shown that adaptation to a frequent stimulus increases the system's sensitivity to rare stimuli. These phenomena were explained in previous work as a result of complex interactions between the various subpopulations of the network. A formal description and analysis of neuronal systems, however, is hindered by the network's heterogeneity and by the multitude of processes taking place at different time-scales. Viewing neural networks as populations of interacting elements, we develop a framework that facilitates a formal analysis of complex, structured, heterogeneous networks. The formulation developed is based on an analysis of the availability of activity dependent resources, and their effects on network responsiveness. This approach offers a simple mechanistic explanation for selective adaptation, and leads to several predictions that were corroborated in both computer simulations and in cultures of cortical neurons developing in vitro. The framework is sufficiently general to apply to different biological systems, and was demonstrated in two different cases.

  12. Hypervisibility and self-disclosure: new textures of social experience in the social networks

    Directory of Open Access Journals (Sweden)

    Carla de Abreu

    2015-12-01

    Full Text Available The emergence of social networks has changed the forms of expression and socialization in contemporary societies, influencing the ways in which we relate to the other and to the visualities. Today, people are learning to manage qualitatively aspects of their identity to be posted in social interfaces and experimenting new placements of gender and sexuality. The reflections of the article come from the partial results of the doctoral research. The article examines the practices of see and be seen in social networks, in particular, focusing on two vital issues in order to understand the experiences from the digital perspective: hypervisibility and self-disclosure.

  13. Position-sensitive Si pad detectors for electron emission channeling experiments

    CERN Document Server

    Wahl, Ulrich; Czermak, Adam; Jahn, S G; Jalocha, Pawel; Marques, J G; Rudge, Alan; Schopper, Florian; Carvalho-Soares, João; Vantomme, A; Weilhammer, Peter

    2004-01-01

    Position-sensitive detector systems, initially developed for the detection of X-rays, have been adapted for their use in electron emission channeling experiments. Each detection system consists of a 30.8x30.8 mm$^{2}$ 22x22 -pad Si detector, either of 0.3 mm, 0.5 mm or 1 mm thickness, four 128$-$channel preamplifier chips, a backplane trigger circuit, a sampling analog to digital converter, a digital signal processor, and a personal computer for data display and storage. The operational principle of these detection systems is described, and characteristic features such as energy and position resolution and maximum count rate, which have been determined from tests with conversion electrons and $\\beta^-\\!$ -particles in the energy range 40--600 keV, are presented.

  14. Experience and attitude of interns to pelvic and sensitive area examinations during their undergraduate medical course.

    Science.gov (United States)

    Alnassar, Sami A; Almuhaya, Reham A; Al-Shaikh, Ghadeer K; Alsaadi, Muslim M; Azer, Samy A; Isnani, Arthur C

    2012-05-01

    To explore the experience of interns in sensitive area examination during their undergraduate medical course and identify factors interfering with such examinations. A cross sectional study was carried out from May to June 2010. Interns (n=315) at King Saud University College of Medicine were invited via email to complete a web-based questionnaire developed using surveymonkey.com. Out of 315 interns, 211 completed the questionnaire; 60% males and 40% females. The mean percentage of interns who never performed any of these examinations was 28.9% for digital rectal examination, 17.5% for breast, 43.1% for female pelvic examination, 13.3% for inguinal (hernia), and 34.6% for male external genitalia. Compared to females, male students conducted more rectal examinations (87 versus 63, parea examinations included patient's refusal (33.1%), and examining patients of opposite gender (27.6%). Confidence in performance of these examinations was correlated to increased frequency of the examination. This study highlights that most common factors interfering with the students' conducting sensitive area examinations are patient's refusal and examining patients of the opposite sex. There is a strong correlation between increased frequency of conducting an examination and student's confidence in performance.

  15. Early experience shapes amygdala sensitivity to race: an international adoption design.

    Science.gov (United States)

    Telzer, Eva H; Flannery, Jessica; Shapiro, Mor; Humphreys, Kathryn L; Goff, Bonnie; Gabard-Durman, Laurel; Gee, Dylan D; Tottenham, Nim

    2013-08-14

    In the current study, we investigated how complete infant deprivation to out-group race impacts behavioral and neural sensitivity to race. Although monkey models have successfully achieved complete face deprivation in early life, this is typically impossible in human studies. We overcame this barrier by examining youths with exclusively homogenous racial experience in early postnatal development. These were youths raised in orphanage care in either East Asia or Eastern Europe as infants and later adopted by American families. The use of international adoption bolsters confidence of infant exposure to race (e.g., to solely Asian faces or European faces). Participants completed an emotional matching task during functional MRI. Our findings show that deprivation to other-race faces in infancy disrupts recognition of emotion and results in heightened amygdala response to out-group faces. Greater early deprivation (i.e., later age of adoption) is associated with greater biases to race. These data demonstrate how early social deprivation to race shapes amygdala function later in life and provides support that early postnatal development may represent a sensitive period for race perception.

  16. Cross-section sensitivity and uncertainty analysis of the FNG copper benchmark experiment

    Energy Technology Data Exchange (ETDEWEB)

    Kodeli, I., E-mail: ivan.kodeli@ijs.si [Jožef Stefan Institute, Jamova 39, SI-1000 Ljubljana (Slovenia); Kondo, K. [Karlsruhe Institute of Technology, Postfach 3640, D-76021 Karlsruhe (Germany); Japan Atomic Energy Agency, Rokkasho-mura (Japan); Perel, R.L. [Racah Institute of Physics, Hebrew University of Jerusalem, IL-91904 Jerusalem (Israel); Fischer, U. [Karlsruhe Institute of Technology, Postfach 3640, D-76021 Karlsruhe (Germany)

    2016-11-01

    A neutronics benchmark experiment on copper assembly was performed end 2014–beginning 2015 at the 14-MeV Frascati neutron generator (FNG) of ENEA Frascati with the objective to provide the experimental database required for the validation of the copper nuclear data relevant for ITER design calculations, including the related uncertainties. The paper presents the pre- and post-analysis of the experiment performed using cross-section sensitivity and uncertainty codes, both deterministic (SUSD3D) and Monte Carlo (MCSEN5). Cumulative reaction rates and neutron flux spectra, their sensitivity to the cross sections, as well as the corresponding uncertainties were estimated for different selected detector positions up to ∼58 cm in the copper assembly. This permitted in the pre-analysis phase to optimize the geometry, the detector positions and the choice of activation reactions, and in the post-analysis phase to interpret the results of the measurements and the calculations, to conclude on the quality of the relevant nuclear cross-section data, and to estimate the uncertainties in the calculated nuclear responses and fluxes. Large uncertainties in the calculated reaction rates and neutron spectra of up to 50%, rarely observed at this level in the benchmark analysis using today's nuclear data, were predicted, particularly high for fast reactions. Observed C/E (dis)agreements with values as low as 0.5 partly confirm these predictions. Benchmark results are therefore expected to contribute to the improvement of both cross section as well as covariance data evaluations.

  17. Collaborating on Facebook: Teachers Exchanging Experiences Through Social Networking Sites

    Directory of Open Access Journals (Sweden)

    da Cunha Júnior F.,

    2016-12-01

    Full Text Available This study explores the use of Facebook for educational purposes, as a collaborative online space for enabling communication among teachers from different schools. The article describes how a group of 43 teachers on Facebook, from various schools in the southeast region of Brazil used a group on Facebook as a collaborative space for communicating among each other. On the group, these teachers shared experiences about the use of digital technologies in their secondary education classes. This study is based on Cultural Historical Activity Theory, considering the group on Facebook as a tool for mediating communication . The objective of this study is to explore why and how teachers collaborated with each other on Facebook, and to study how communication among them evolved in the process. We examined the posts on that group from 2012 to 2014, and two questionnaires responded online by the teachers in June 2012 and in December 2013. Our findings suggest that teachers tend to critically collaborate in smaller groups and that further online communication evolved outside the group of teachers, with the creation of smaller groups on Facebook inside their schools.

  18. New Technologies for Information and Communication, PWM Remote Experimenting and 3G Networks as Teaching Support

    Directory of Open Access Journals (Sweden)

    Juarez B. Silva

    2012-01-01

    Full Text Available Remote experiments may be an important tool to implement new technologies in the teaching/learning process, since it enables experimenting with real plants, essential to consolidate the concepts acquired in the theoretical classes, especially in technical and scientific disciplines.This article presents the “modulator PWM” remote experiment, its operational architecture and construction. It seeks to demonstrate its integration with theory and the use of the 3G cellular network as a communications channel for remote experimenting. The PWM modulators are often used in disciplines of higher education courses in electrical engineering, telecommunications and electronics. This article shows that it is possible to perform the practical activity completely remotely, via 3G cellular networks or through the internet to access the experiment and perform the experiments needed to fully understand the theories of the PWM modulator.This article is a further initiative for remote experiments in the world of different engineering specialties, involving the cellular networks that are rapidly expanding at this time.

  19. Ranking terrorists in networks : A sensitivity analysis of Al Qaeda’s 9/11 attack

    NARCIS (Netherlands)

    Husslage, B.G.M.; Borm, Peter; Burg, T.; Hamers, Herbert

    All over the world intelligence services are collecting data concerning possible terrorist threats. This information is usually transformed into network structures in which the nodes represent the individuals in the data set and the links possible connections between these individuals.

  20. Ranking Terrorists in Networks : A Sensitivity Analysis of Al Qaeda’s 9/11 Attack

    NARCIS (Netherlands)

    Husslage, B.G.M.; Borm, P.E.M.; Burg, T.; Hamers, H.J.M.; Lindelauf, R.

    2014-01-01

    All over the world intelligence services are collecting data concerning possible terrorist threats. This information is usually transformed into network structures in which the nodes represent the individuals in the data set and the links possible connections between these individuals.

  1. Ecological networks are more sensitive to plant than to animal extinction under climate change

    OpenAIRE

    Schleuning, Matthias; Fründ, Jochen; Schweiger, Oliver; Welk, Erik; Albrecht, Jörg; Albrecht, Matthias; Beil, Marion; Benadi, Gita; Blüthgen, Nico; Bruelheide, Helge; Böhning-Gaese, Katrin; Dehling, D. Matthias; Dormann, Carsten F.; Exeler, Nina; Farwig, Nina

    2016-01-01

    Impacts of climate change on individual species are increasingly well documented, but we lack understanding of how these effects propagate through ecological communities. Here we combine species distribution models with ecological network analyses to test potential impacts of climate change on >700 plant and animal species in pollination and seed-dispersal networks from central Europe. We discover that animal species that interact with a low diversity of plant species have narrow climatic nic...

  2. Influence of Ethnic-Related Diversity Experiences on Intercultural Sensitivity of Students at a Public University in Malaysia

    Science.gov (United States)

    Tamam, Ezhar; Abdullah, Ain Nadzimah

    2012-01-01

    In this study, the authors examine the influence of ethnic-related diversity experiences on intercultural sensitivity among Malaysian students at a multiethnic, multicultural and multilingual Malaysian public university. Results reveal a significant differential level of ethnic-related diversity experiences (but not at the level of intercultural…

  3. Continuous-variable Measurement-device-independent Quantum Relay Network with Phase-sensitive Amplifiers

    Science.gov (United States)

    Li, Fei; Zhao, Wei; Guo, Ying

    2017-09-01

    Continuous-variable (CV) measurement-device-independent (MDI) quantum cryptography is now heading towards solving the practical problem of implementing scalable quantum networks. In this paper, we show that a solution can come from deploying an optical amplifier in the CV-MDI system, aiming to establish a high-rate quantum network. We suggest an improved CV-MDI protocol using the EPR states coupled with optical amplifiers. It can implement a practical quantum network scheme, where the legal participants create the secret correlations by using EPR states connecting to an untrusted relay via insecure links and applying the multi-entangled Greenberger-Horne-Zeilinger (GHZ) state analysis at relay station. Despite the possibility that the relay could be completely tampered with and imperfect links are subject to the powerful attacks, the legal participants are still able to extract a secret key from network communication. The numerical simulation indicates that the quantum network communication can be achieved in an asymmetric scenario, fulfilling the demands of a practical quantum network. Furthermore, we show that the use of optical amplifiers can compensate the inherent imperfections and improve the secret key rate of the CV-MDI system.

  4. Differences in Friendship Networks and Experiences of Cyberbullying Among Korean and Australian Adolescents.

    Science.gov (United States)

    Lee, Jee Young; Kwon, Yeji; Yang, Soeun; Park, Sora; Kim, Eun-Mee; Na, Eun-Yeong

    2017-01-01

    Cyberbullying is one of the negative consequences of online social interaction. The digital environment enables adolescents to engage in online social interaction beyond the traditional physical boundaries of families, neighborhoods, and schools. The authors examined connections to friendship networks in both online and offline settings are related to their experiences as victims, perpetrators, and bystanders of cyberbullying. A comparative face-to-face survey of adolescents (12-15-year-olds) was conducted in Korea (n = 520) and Australia (n = 401). The results reveal that online networks are partially related to cyberbullying in both countries, showing the size of social network sites was significantly correlated with experience cyberbullying among adolescents in both countries. However there were cultural differences in the impact of friendship networks on cyberbullying. The size of the online and offline networks has a stronger impact on the cyberbullying experiences in Korea than it does in Australia. In particular, the number of friends in cliques was positively related to both bullying and victimization in Korea.

  5. Adolescent Problematic Social Networking and School Experiences: The Mediating Effects of Sleep Disruptions and Sleep Quality.

    Science.gov (United States)

    Vernon, Lynette; Barber, Bonnie L; Modecki, Kathryn L

    2015-07-01

    An important developmental task for adolescents is to become increasingly responsible for their own health behaviors. Establishing healthy sleep routines and controlling media use before bedtime are important for adequate, quality sleep so adolescents are alert during the day and perform well at school. Despite the prevalence of adolescent social media use and the large percentage of computers and cell phones in adolescents' bedrooms, no studies to date have investigated the link between problematic adolescent investment in social networking, their sleep practices, and associated experiences at school. A sample of 1,886 students in Australia aged between 12 and 18 years of age completed self-report data on problematic social networking use, sleep disturbances, sleep quality, and school satisfaction. Structural equation modeling (SEM) substantiated the serial mediation hypothesis: for adolescents, problematic social networking use significantly increased sleep disturbances, which adversely affected perceptions of sleep quality that, in turn, lowered adolescents' appraisals of their school satisfaction. This significant pattern was largely driven by the indirect effect of sleep disturbances. These findings suggest that adolescents are vulnerable to negative consequences from social networking use. Specifically, problematic social networking is associated with poor school experiences, which result from poor sleep habits. Promoting better sleep routines by minimizing sleep disturbances from social media use could improve school experiences for adolescents with enhanced emotional engagement and improved subjective well-being.

  6. Coupling hydrodynamic and wave models: first step and sensitivity experiments in the Mediterranean Sea

    Science.gov (United States)

    Clementi, Emanuela; Oddo, Paolo; Drudi, Massimiliano; Pinardi, Nadia; Korres, Gerasimos; Grandi, Alessandro

    2017-10-01

    This work describes the first step towards a fully coupled modelling system composed of an ocean circulation and a wind wave model. Sensitivity experiments are presented for the Mediterranean Sea where the hydrodynamic model NEMO is coupled with the third-generation wave model WaveWatchIII (WW3). Both models are implemented at 1/16° horizontal resolution and are forced by ECMWF 1/4° horizontal resolution atmospheric fields. The models are two-way coupled at hourly intervals exchanging the following fields: sea surface currents and temperature are transferred from NEMO to WW3 by modifying the mean momentum transfer of waves and the wind speed stability parameter, respectively. The neutral drag coefficient computed by WW3 is then passed to NEMO, which computes the surface stress. Five-year (2009-2013) numerical experiments were carried out in both uncoupled and coupled mode. In order to validate the modelling system, numerical results were compared with coastal and drifting buoys and remote sensing data. The results show that the coupling of currents with waves improves the representation of the wave spectrum. However, the wave-induced drag coefficient shows only minor improvements in NEMO circulation fields, such as temperature, salinity, and currents.

  7. The PIENU experiment at TRIUMF : a sensitive probe for new physics

    Science.gov (United States)

    Malbrunot, Chloé; Aguilar-Arevalo, A. A.; Aoki, M.; Blecher, M.; Britton, D. I.; Bryman, D. A.; Chen, S.; Comfort, J.; Ding, M.; Doornbos, J.; Doria, L.; Gumplinger, P.; Hurst, C.; Hussein, A.; Igarashi, Y.; Ito, N.; Kettell, S.; Kuno, Y.; Kurchaninov, L.; Littenberg, L.; Numao, T.; Poutissou, R.; Sher, A.; Sullivan, T.; Vavilov, D.; Yamada, K.; Yoshida, M.

    2011-09-01

    Study of rare decays is an important approach for exploring physics beyond the Standard Model (SM). The branching ratio of the helicity suppressed pion decays, R = , is one of the most accurately calculated decay process involving hadrons and has so far provided the most stringent test of the hypothesis of electron-muon universality in weak interactions. The branching ratio has been calculated in the SM to better than 0.01% accuracy to be RSM = 1.2353(1) × 10 . The PIENU experiment at TRIUMF, which started taking physics data in September 2009, aims to reach an accuracy five times better than the previous experiments, so as to confront the theoretical calculation at the level of ±0.1%. If a deviation from the RSM is found, "new physics" beyond the SM, at potentially very high mass scales (up to 1000 TeV), could be revealed. Alternatively, sensitive constraints on hypotheses can be obtained for interactions involving pseudoscalar or scalar interactions. So far, 4 million π+ → e+ νe ue events have been accumulated by PIENU. This paper will outline the physics motivations, describe the apparatus and techniques designed to achieve high precision and present the latest results.

  8. Maximising the value of computer experiments using multi-method global sensitivity analysis

    Science.gov (United States)

    Pianosi, F.; Iwema, J.; Rosolem, R.; Wagener, T.

    2015-12-01

    Global Sensitivity Analysis (GSA) is increasingly recognised as an essential technique for a structured and quantitative approach to the calibration and diagnostic evaluation of environmental models. However, the implementation and interpretation of GSA is complicated by a number of choices that users need to make and for which multiple, equally sensible, options are often available. These choices include in the first place the choice of the GSA method, as well as many implementation details like the definition of the sampling space and strategy. The issue is exacerbated by computational complexity, in terms of both computing time and storage space needed to run the model, which might strongly constrain the number of experiments that can be afforded. While several algorithmic improvements can be adopted to reduce the computing burden of specific GSA methods, in this talk we discuss how a multi-method approach can be established to maximise the information gathered from an individual sample of model evaluations. Using as an example the GSA of a land surface model, we show how different analytical and approximation techniques can be applied sequentially to the same sample of model inputs and outputs, providing complimentary information about the model behaviour from different angles, and allowing for testing the impact of the choices made to generate the sample. We further expand our analysis to show how GSA is interconnected with model calibration and uncertainty analysis, so that a careful design of the simulation experiment can be used to address different questions simultaneously.

  9. Undergraduate students' development of social, cultural, and human capital in a networked research experience

    Science.gov (United States)

    Thompson, Jennifer Jo; Conaway, Evan; Dolan, Erin L.

    2016-12-01

    Recent calls for reform in undergraduate biology education have emphasized integrating research experiences into the learning experiences of all undergraduates. Contemporary science research increasingly demands collaboration across disciplines and institutions to investigate complex research questions, providing new contexts and models for involving undergraduates in research. In this study, we examined the experiences of undergraduates participating in a multi-institution and interdisciplinary biology research network. Unlike the traditional apprenticeship model of research, in which a student participates in research under the guidance of a single faculty member, students participating in networked research have the opportunity to develop relationships with additional faculty and students working in other areas of the project, at their own and at other institutions. We examined how students in this network develop social ties and to what extent a networked research experience affords opportunities for students to develop social, cultural, and human capital. Most studies of undergraduate involvement in science research have focused on documenting student outcomes rather than elucidating how students gain access to research experiences or how elements of research participation lead to desired student outcomes. By taking a qualitative approach framed by capital theories, we have identified ways that undergraduates utilize and further develop various forms of capital important for success in science research. In our study of the first 16 months of a biology research network, we found that undergraduates drew upon a combination of human, cultural, and social capital to gain access to the network. Within their immediate research groups, students built multidimensional social ties with faculty, peers, and others, yielding social capital that can be drawn upon for information, resources, and support. They reported developing cultural capital in the form of learning to

  10. Taking data seriously: the value of actor-network theory in rethinking patient experience data.

    Science.gov (United States)

    Desai, Amit; Zoccatelli, Giulia; Adams, Mary; Allen, Davina; Brearley, Sally; Rafferty, Anne Marie; Robert, Glenn; Donetto, Sara

    2017-04-01

    Hospitals are awash with patient experience data, much of it collected with the ostensible purpose of improving the quality of patient care. However, there has been comparatively little consideration of the nature and capacities of data itself. Using insights from actor-network theory, we propose that paying attention to patient experience data as having agency in particular hospital interactions allows us to better trace how and in what circumstances data lead (or fail to lead) to quality improvement.

  11. The impact of public housing on social networks: a natural experiment.

    Science.gov (United States)

    Pollack, Craig E; Green, Harold D; Kennedy, David P; Griffin, Beth Ann; Kennedy-Hendricks, Alene; Burkhauser, Susan; Schwartz, Heather

    2014-09-01

    We assessed whether 2 types of public housing-scattered among market-rate housing developments or clustered in small public housing projects-were associated with the perceived health and health behaviors of residents' social networks. Leveraging a natural experiment in Montgomery County, Maryland, in which residents were randomly assigned to different types of public housing, we surveyed 453 heads of household in 2011. We asked residents about their own health as well as the perceived health of their network members, including their neighbors. Residents in scattered-site public housing perceived that their neighbors were more likely to exercise than residents of clustered public housing (24.7% of network members vs 14.0%; P housing have a modest impact on the health composition of one's social network, suggesting the importance of housing policy for health.

  12. OSCAR experiment high-density network data report: Event 1 - April 8-9, 1981

    Energy Technology Data Exchange (ETDEWEB)

    Dana, M.T.; Easter, R.C.; Thorp, J.M.

    1984-12-01

    The OSCAR (Oxidation and Scavenging Characteristics of April Rains) experiment, conducted during April 1981, was a cooperative field investigation of wet removal in cyclonic storm systems. The high-densiy component of OSCAR was located in northeast Indiana and included sequential precipitation chemistry measurements on a 100 by 100 km network, as well as airborne air chemistry and cloud chemistry measurements, surface air chemistry measurements, and supporting meteorological measurements. Four separate storm events were studied during the experiment. This report summarizes data taken by Pacific Northwest Laboratory (PNL) during the first storm event, April 8-9. The report contains the high-density network precipitation chemistry data, air chemistry data from the PNL aircraft, and meteorological data for the event, including standard National Weather Service products and radar data from the network. 4 references, 72 figures, 5 tables.

  13. Experimenting with ecosystem interaction networks in search of threshold potentials in real-world marine ecosystems.

    Science.gov (United States)

    Thrush, Simon F; Hewitt, Judi E; Parkes, Samantha; Lohrer, Andrew M; Pilditch, Conrad; Woodin, Sarah A; Wethey, David S; Chiantore, Mariachiara; Asnaghi, Valentina; De Juan, Silvia; Kraan, Casper; Rodil, Ivan; Savage, Candida; Van Colen, Carl

    2014-06-01

    Thresholds profoundly affect our understanding and management of ecosystem dynamics, but we have yet to develop practical techniques to assess the risk that thresholds will be crossed. Combining ecological knowledge of critical system interdependencies with a large-scale experiment, we tested for breaks in the ecosystem interaction network to identify threshold potential in real-world ecosystem dynamics. Our experiment with the bivalves Macomona liliana and Austrovenus stutchburyi on marine sandflats in New Zealand demonstrated that reductions in incident sunlight changed the interaction network between sediment biogeochemical fluxes, productivity, and macrofauna. By demonstrating loss of positive feedbacks and changes in the architecture of the network, we provide mechanistic evidence that stressors lead to break points in dynamics, which theory predicts predispose a system to a critical transition.

  14. OSCAR experiment high-density network data report: Event 3 - April 16-17, 1981

    Energy Technology Data Exchange (ETDEWEB)

    Dana, M.T.; Easter, R.C.; Thorp, J.M.

    1984-12-01

    The OSCAR (Oxidation and Scavenging Characteristics of April Rains) experiment, conducted during April 1981, was a cooperative field investigation of wet removal in cyclonic storm systems. The high-density component of OSCAR was located in northeast Indiana and included sequential precipitation chemistry measurements on a 100 by 100 km network, as well as airborne air chemistry and cloud chemistry measurements, surface air chemistry measurements, and supporting meteorological measurements. Four separate storm events were studied during the experiment. This report summarizes data taken by Pacific Northwest Laboratory (PNL) during the third storm event, April 16-17. The report contains the high-density network precipitation chemistry data, air chemistry and cloud chemistry data from the PNL aircraft, and meteorological data for the event, including standard National Weather Service products and radar and rawindsonde data from the network. 4 references, 76 figures, 6 tables.

  15. Adjoint-based sensitivity analysis of low-order thermoacoustic networks using a wave-based approach

    Science.gov (United States)

    Aguilar, José G.; Magri, Luca; Juniper, Matthew P.

    2017-07-01

    Strict pollutant emission regulations are pushing gas turbine manufacturers to develop devices that operate in lean conditions, with the downside that combustion instabilities are more likely to occur. Methods to predict and control unstable modes inside combustion chambers have been developed in the last decades but, in some cases, they are computationally expensive. Sensitivity analysis aided by adjoint methods provides valuable sensitivity information at a low computational cost. This paper introduces adjoint methods and their application in wave-based low order network models, which are used as industrial tools, to predict and control thermoacoustic oscillations. Two thermoacoustic models of interest are analyzed. First, in the zero Mach number limit, a nonlinear eigenvalue problem is derived, and continuous and discrete adjoint methods are used to obtain the sensitivities of the system to small modifications. Sensitivities to base-state modification and feedback devices are presented. Second, a more general case with non-zero Mach number, a moving flame front and choked outlet, is presented. The influence of the entropy waves on the computed sensitivities is shown.

  16. Using Social Networks to Enhance Teaching and Learning Experiences in Higher Learning Institutions

    Science.gov (United States)

    Balakrishnan, Vimala

    2014-01-01

    The paper first explores the factors that affect the use of social networks to enhance teaching and learning experiences among students and lecturers, using structured questionnaires prepared based on the Push-Pull-Mooring framework. A total of 455 students and lecturers from higher learning institutions in Malaysia participated in this study.…

  17. Building and Sustaining Citywide Afterschool Initiatives: Experiences of the Cross-Cities Network Citywide Afterschool Initiatives.

    Science.gov (United States)

    Hall, Georgia; Harvey, Brooke

    This paper highlights the experiences of several citywide after school initiatives from the Cross-Cities Network, describing activities and strategies that contributed to building operational and sustainable citywide delivery of out-of-school time programs. The paper presents evidence of success and notes lessons learned, identifying key elements…

  18. The Student Experience of Learning Using Networked Technologies: An Emergent Progression of Expanding Awareness

    Science.gov (United States)

    Cutajar, Maria

    2017-01-01

    This article reports on phenomenographic research which explored the qualitative differences in post-secondary students' accounts of their networked learning experiences. Data was generated using semi-structured interviews with a purposive sample of participants. Phenomenographic analysis led to a configuration of variation in students' accounts…

  19. Online Social Networks as Formal Learning Environments: Learner Experiences and Activities

    Science.gov (United States)

    Veletsianos, George; Navarrete, Cesar C.

    2012-01-01

    While the potential of social networking sites to contribute to educational endeavors is highlighted by researchers and practitioners alike, empirical evidence on the use of such sites for formal online learning is scant. To fill this gap in the literature, we present a case study of learners' perspectives and experiences in an online course…

  20. Experiences from Implementing a Mobile Multiplayer Real-Time Game for Wireless Networks with High Latency

    Directory of Open Access Journals (Sweden)

    Alf Inge Wang

    2009-01-01

    Full Text Available This paper describes results and experiences from designing, implementing, and testing a multiplayer real-time game over mobile networks with high latency. The paper reports on network latency and bandwidth measurements from playing the game live over GPRS, EDGE, UMTS, and WLAN using the TCP and the UDP protocols. These measurements describe the practical constraints of various wireless networks and protocols when used for mobile multiplayer game purposes. Further, the paper reports on experiences from implementing various approaches to minimize issues related to high latency. Specifically, the paper focuses on a discussion about how much of the game should run locally on the client versus on the server to minimize the load on the mobile device and obtain sufficient consistency in the game. The game was designed to reveal all kinds of implementation issues of mobile network multiplayer games. The goal of the game is for a player to push other players around and into traps where they loose their lives. The game relies heavily on collision detection between the players and game objects. The paper presents experiences from experimenting with various approaches that can be used to handle such collisions, and highlights the advantages and disadvantages of the various approaches.

  1. Independent functional connectivity networks underpin food and monetary reward sensitivity in excess weight.

    Science.gov (United States)

    Verdejo-Román, Juan; Fornito, Alex; Soriano-Mas, Carles; Vilar-López, Raquel; Verdejo-García, Antonio

    2017-02-01

    Overvaluation of palatable food is a primary driver of obesity, and is associated with brain regions of the reward system. However, it remains unclear if this network is specialized in food reward, or generally involved in reward processing. We used functional magnetic resonance imaging (fMRI) to characterize functional connectivity during processing of food and monetary rewards. Thirty-nine adults with excess weight and 37 adults with normal weight performed the Willingness to Pay for Food task and the Monetary Incentive Delay task in the fMRI scanner. A data-driven graph approach was applied to compare whole-brain, task-related functional connectivity between groups. Excess weight was associated with decreased functional connectivity during the processing of food rewards in a network involving primarily frontal and striatal areas, and increased functional connectivity during the processing of monetary rewards in a network involving principally frontal and parietal areas. These two networks were topologically and anatomically distinct, and were independently associated with BMI. The processing of food and monetary rewards involve segregated neural networks, and both are altered in individuals with excess weight. Copyright © 2016 Elsevier Inc. All rights reserved.

  2. The CANDELLE experiment for characterization of neutron sensitivity of LiF TLDs

    Science.gov (United States)

    Guillou, M. Le; Billebaud, A.; Gruel, A.; Kessedjian, G.; Méplan, O.; Destouches, C.; Blaise, P.

    2018-01-01

    As part of the design studies conducted at CEA for future power and research nuclear reactors, the validation of neutron and photon calculation schemes related to nuclear heating prediction are strongly dependent on the implementation of nuclear heating measurements. Such measurements are usually performed in low-power reactors, whose core dimensions are accurately known and where irradiation conditions (power, flux and temperature) are entirely controlled. Due to the very low operating power of such reactors (of the order of 100 W), nuclear heating is assessed by using dosimetry techniques such as thermoluminescent dosimeters (TLDs). However, although they are highly sensitive to gamma radiation, such dosimeters are also, to a lesser extent, sensitive to neutrons. The neutron dose depends strongly on the TLD composition, typically contributing to 10-30% of the total measured dose in a mixed neutron/gamma field. The experimental determination of the neutron correction appears therefore to be crucial to a better interpretation of doses measured in reactor with reduced uncertainties. A promising approach based on the use of two types of LiF TLDs respectively enriched with lithium-6 and lithium-7, precalibrated both in photon and neutron fields, has been recently developed at INFN (Milan, Italy) for medical purposes. The CANDELLE experiment is dedicated to the implementation of a pure neutron field "calibration" of TLDs by using the GENEPI-2 neutron source of LPSC (Grenoble, France). Those irradiation conditions allowed providing an early assessment of the neutron components of doses measured in EOLE reactor at CEA Cadarache with 10% uncertainty at 1σ.

  3. Ecological networks are more sensitive to plant than to animal extinction under climate change.

    Science.gov (United States)

    Schleuning, Matthias; Fründ, Jochen; Schweiger, Oliver; Welk, Erik; Albrecht, Jörg; Albrecht, Matthias; Beil, Marion; Benadi, Gita; Blüthgen, Nico; Bruelheide, Helge; Böhning-Gaese, Katrin; Dehling, D Matthias; Dormann, Carsten F; Exeler, Nina; Farwig, Nina; Harpke, Alexander; Hickler, Thomas; Kratochwil, Anselm; Kuhlmann, Michael; Kühn, Ingolf; Michez, Denis; Mudri-Stojnić, Sonja; Plein, Michaela; Rasmont, Pierre; Schwabe, Angelika; Settele, Josef; Vujić, Ante; Weiner, Christiane N; Wiemers, Martin; Hof, Christian

    2016-12-23

    Impacts of climate change on individual species are increasingly well documented, but we lack understanding of how these effects propagate through ecological communities. Here we combine species distribution models with ecological network analyses to test potential impacts of climate change on >700 plant and animal species in pollination and seed-dispersal networks from central Europe. We discover that animal species that interact with a low diversity of plant species have narrow climatic niches and are most vulnerable to climate change. In contrast, biotic specialization of plants is not related to climatic niche breadth and vulnerability. A simulation model incorporating different scenarios of species coextinction and capacities for partner switches shows that projected plant extinctions under climate change are more likely to trigger animal coextinctions than vice versa. This result demonstrates that impacts of climate change on biodiversity can be amplified via extinction cascades from plants to animals in ecological networks.

  4. Ecological networks are more sensitive to plant than to animal extinction under climate change

    Science.gov (United States)

    Schleuning, Matthias; Fründ, Jochen; Schweiger, Oliver; Welk, Erik; Albrecht, Jörg; Albrecht, Matthias; Beil, Marion; Benadi, Gita; Blüthgen, Nico; Bruelheide, Helge; Böhning-Gaese, Katrin; Dehling, D. Matthias; Dormann, Carsten F.; Exeler, Nina; Farwig, Nina; Harpke, Alexander; Hickler, Thomas; Kratochwil, Anselm; Kuhlmann, Michael; Kühn, Ingolf; Michez, Denis; Mudri-Stojnić, Sonja; Plein, Michaela; Rasmont, Pierre; Schwabe, Angelika; Settele, Josef; Vujić, Ante; Weiner, Christiane N.; Wiemers, Martin; Hof, Christian

    2016-01-01

    Impacts of climate change on individual species are increasingly well documented, but we lack understanding of how these effects propagate through ecological communities. Here we combine species distribution models with ecological network analyses to test potential impacts of climate change on >700 plant and animal species in pollination and seed-dispersal networks from central Europe. We discover that animal species that interact with a low diversity of plant species have narrow climatic niches and are most vulnerable to climate change. In contrast, biotic specialization of plants is not related to climatic niche breadth and vulnerability. A simulation model incorporating different scenarios of species coextinction and capacities for partner switches shows that projected plant extinctions under climate change are more likely to trigger animal coextinctions than vice versa. This result demonstrates that impacts of climate change on biodiversity can be amplified via extinction cascades from plants to animals in ecological networks. PMID:28008919

  5. SBMLsqueezer 2: context-sensitive creation of kinetic equations in biochemical networks

    DEFF Research Database (Denmark)

    Draeger, Andreas; Zielinski, Daniel C.; Keller, Roland

    2015-01-01

    Background: The size and complexity of published biochemical network reconstructions are steadily increasing, expanding the potential scale of derived computational models. However, the construction of large biochemical network models is a laborious and error-prone task. Automated methods have...... simplified the network reconstruction process, but building kinetic models for these systems is still a manually intensive task. Appropriate kinetic equations, based upon reaction rate laws, must be constructed and parameterized for each reaction. The complex test-and-evaluation cycles that can be involved...... desired. Conclusions: The described approach fills a heretofore absent niche in workflows for large-scale biochemical kinetic model construction. In several applications the algorithm has already been demonstrated to be useful and scalable. SBMLsqueezer is platform independent and can be used as a stand...

  6. Verification and optimal control of context-sensitive probabilistic Boolean networks using model checking and polynomial optimization.

    Science.gov (United States)

    Kobayashi, Koichi; Hiraishi, Kunihiko

    2014-01-01

    One of the significant topics in systems biology is to develop control theory of gene regulatory networks (GRNs). In typical control of GRNs, expression of some genes is inhibited (activated) by manipulating external stimuli and expression of other genes. It is expected to apply control theory of GRNs to gene therapy technologies in the future. In this paper, a control method using a Boolean network (BN) is studied. A BN is widely used as a model of GRNs, and gene expression is expressed by a binary value (ON or OFF). In particular, a context-sensitive probabilistic Boolean network (CS-PBN), which is one of the extended models of BNs, is used. For CS-PBNs, the verification problem and the optimal control problem are considered. For the verification problem, a solution method using the probabilistic model checker PRISM is proposed. For the optimal control problem, a solution method using polynomial optimization is proposed. Finally, a numerical example on the WNT5A network, which is related to melanoma, is presented. The proposed methods provide us useful tools in control theory of GRNs.

  7. Dynamic control of adsorption sensitivity for photo-EMF-based ammonia gas sensors using a wireless network.

    Science.gov (United States)

    Vashpanov, Yuriy; Choo, Hyunseung; Kim, Dongsoo Stephen

    2011-01-01

    This paper proposes an adsorption sensitivity control method that uses a wireless network and illumination light intensity in a photo-electromagnetic field (EMF)-based gas sensor for measurements in real time of a wide range of ammonia concentrations. The minimum measurement error for a range of ammonia concentration from 3 to 800 ppm occurs when the gas concentration magnitude corresponds with the optimal intensity of the illumination light. A simulation with LabView-engineered modules for automatic control of a new intelligent computer system was conducted to improve measurement precision over a wide range of gas concentrations. This gas sensor computer system with wireless network technology could be useful in the chemical industry for automatic detection and measurement of hazardous ammonia gas levels in real time.

  8. Dynamic Control of Adsorption Sensitivity for Photo-EMF-Based Ammonia Gas Sensors Using a Wireless Network

    Directory of Open Access Journals (Sweden)

    Yuriy Vashpanov

    2011-11-01

    Full Text Available This paper proposes an adsorption sensitivity control method that uses a wireless network and illumination light intensity in a photo-electromagnetic field (EMF-based gas sensor for measurements in real time of a wide range of ammonia concentrations. The minimum measurement error for a range of ammonia concentration from 3 to 800 ppm occurs when the gas concentration magnitude corresponds with the optimal intensity of the illumination light. A simulation with LabView-engineered modules for automatic control of a new intelligent computer system was conducted to improve measurement precision over a wide range of gas concentrations. This gas sensor computer system with wireless network technology could be useful in the chemical industry for automatic detection and measurement of hazardous ammonia gas levels in real time.

  9. Modeling and Optimization of M/G/1-Type Queueing Networks: An Efficient Sensitivity Analysis Approach

    Directory of Open Access Journals (Sweden)

    Liang Tang

    2010-01-01

    Full Text Available A mathematical model for M/G/1-type queueing networks with multiple user applications and limited resources is established. The goal is to develop a dynamic distributed algorithm for this model, which supports all data traffic as efficiently as possible and makes optimally fair decisions about how to minimize the network performance cost. An online policy gradient optimization algorithm based on a single sample path is provided to avoid suffering from a “curse of dimensionality”. The asymptotic convergence properties of this algorithm are proved. Numerical examples provide valuable insights for bridging mathematical theory with engineering practice.

  10. Synchronous Databus Network in ITER: Open source real-time network for the next nuclear fusion experiment

    Energy Technology Data Exchange (ETDEWEB)

    Boncagni, L.; Centioli, C. [Associazione EURATOM-ENEA sulla Fusione, C.R.ENEA Frascati, Rome (Italy); Iannone, F. [Associazione EURATOM-ENEA sulla Fusione, C.R.ENEA Frascati, Rome (Italy)], E-mail: francesco.iannone@frascati.enea.it; Neri, C.; Panella, M.; Pangione, L.; Riva, M. [Associazione EURATOM-ENEA sulla Fusione, C.R.ENEA Frascati, Rome (Italy); Scappaticci, M. [Dipartimento di Informatica, Sistemi e Produzione, Universita di Tor Vergata, Rome (Italy); Vitale, V. [Associazione EURATOM-ENEA sulla Fusione, C.R.ENEA Frascati, Rome (Italy); Zaccarian, L. [Dipartimento di Informatica, Sistemi e Produzione, Universita di Tor Vergata, Rome (Italy)

    2008-04-15

    The next nuclear fusion experiment, ITER, is providing the infrastructure for the optimal operation of a burning plasma, requiring feedback control of discharge parameters and on-line evaluation of computationally intensive models running in a cluster of controller nodes. Thus, the synchronization of the available information on the plasma and plant state variables among the controller nodes is a key issue for ITER. The ITER conceptual design aims to perform feedback control on a cluster of distributed controllers connected by a Synchronous Databus Network (SDN). Therefore it is mandatory to achieve a deterministic data exchange among the controller nodes with a refresh rate of at least 1 kHz and a jitter of at least 50 {mu}s. Thus, a conservative estimate of the data flow within the controller network can be 3 kSample/ms. In this paper the open source RTnet project is evaluated to meet the requirements of the SDN of ITER. A testbed involving a cluster of eight nodes connected over a standard ethernet network has been set up to simulate a distributed real-time control system. The main goal of the test is to verify the compliance of the performance with the ITER SDN requirements.

  11. Network-Centric Maritime Radiation Awareness and Interdiction Experiments: C2 Experimentation

    Energy Technology Data Exchange (ETDEWEB)

    Bordetsky, A; Dougan, A D; Nekoogar, F

    2006-08-07

    The paper addresses technological and operational challenges of developing a global plug-and-play Maritime Domain Security testbed for the Global War on Terrorism mission. This joint NPS-LLNL project is based on the NPS Tactical Network Topology (TNT) composed of long-haul OFDM networks combined with self-forming wireless mesh links to air, surface, ground, and underwater unmanned vehicles. This long-haul network is combined with ultra-wideband (UWB) communications systems for wireless communications in harsh radio propagation channels. LLNL's UWB communication prototypes are designed to overcome shortcomings of the present narrowband communications systems in heavy metallic and constricted corridors inside ships. In the center of our discussion are networking solutions for the Maritime Interdiction Operation (MIO) Experiments in which geographically distributed command centers and subject matter experts collaborate with the Boarding Party in real time to facilitate situational understanding and course of action selection. The most recent experiment conducted via the testbed extension to the Alameda Island exercised several key technologies aimed at improving MIO. These technologies included UWB communications from within the ship to Boarding Party leader sending data files and pictures, advanced radiation detection equipment for search and identification, biometric equipment to record and send fingerprint files to facilitate rapid positive identification of crew members, and the latest updates of the NPS Tactical Network Topology facilitating reachback to LLNL, Biometric Fusion Center, USCG, and DTRA experts.

  12. Revealing Fundamental Physics from the Daya Bay Neutrino Experiment using Deep Neural Networks

    CERN Document Server

    Racah, Evan; Sadowski, Peter; Bhimji, Wahid; Tull, Craig; Oh, Sang-Yun; Baldi, Pierre; Prabhat,

    2016-01-01

    Experiments in particle physics produce enormous quantities of data that must be analyzed and interpreted by teams of physicists. This analysis is often exploratory, where scientists are unable to enumerate the possible types of signal prior to performing the experiment. Thus, tools for summarizing, clustering, visualizing and classifying high-dimensional data are essential. In this work, we show that meaningful physical content can be revealed by transforming the raw data into a learned high-level representation using deep neural networks, with measurements taken at the Daya Bay Neutrino Experiment as a case study. We further show how convolutional deep neural networks can provide an effective classification filter with greater than 97% accuracy across different classes of physics events, significantly better than other machine learning approaches.

  13. Sensitive quantitative predictions of peptide-MHC binding by a 'Query by Committee' artificial neural network approach

    DEFF Research Database (Denmark)

    Buus, S.; Lauemoller, S.L.; Worning, Peder

    2003-01-01

    We have generated Artificial Neural Networks (ANN) capable of performing sensitive, quantitative predictions of peptide binding to the MHC class I molecule, HLA-A*0204. We have shown that such quantitative ANN are superior to conventional classification ANN, that have been trained to predict...... binding vs non-binding peptides. Furthermore, quantitative ANN allowed a straightforward application of a 'Query by Committee' (QBC) principle whereby particularly information-rich peptides could be identified and subsequently tested experimentally. Iterative training based on QBC-selected peptides...

  14. Trans-Pacific HDR Satellite Communications Experiment Phase-2 Project Plan and Experimental Network

    Science.gov (United States)

    Hsu, Eddie; Kadowaki, Naoto; Yoshimura, Naoko; Takahashi, Takashi; Yoshikawa, Makoto; Bergman, Larry; Bhasin, Kul

    2000-01-01

    The trans-Pacific high data rate (TP-HDR) satellite communications experiment was proposed at the Japan-U.S. Cooperation in Space (JUCS) Program Workshop held in Hawaii in 1993 and remote high definition video post-production was demonstrated as the first phase trial. ATM-based 45 Mbps trans-Pacific link was established in the first phase, and the following experiments with 155 Mbps was planned as the phase 2. This paper describes the experimental network configuration and project plan of TP-HDR experiment phase 2. Additional information is provided in the original.

  15. STUDY OF SENSITIVITY OF THE PARAMETERS OF A GENETIC ALGORITHM FOR DESIGN OF WATER DISTRIBUTION NETWORKS

    Directory of Open Access Journals (Sweden)

    Pedro L. Iglesias

    2007-12-01

    Full Text Available The Genetic Algorithms (GAs are a technique of optimization used for water distribution networks design. This work has been made with a modified pseudo genetic algorithm (PGA, whose main variation with a classical GA is a change in the codification of the chromosomes, which is made of numerical form instead of the binary codification. This variation entails a series of special characteristics in the codification and in the definition of the operations of mutation and crossover. Initially, the work displays the results of the PGA on a water network studied in the literature. The results show the kindness of the method. Also is made a statistical analysis of the obtained solutions. This analysis allows verifying the values of mutation and crossing probability more suitable for the proposed method. Finally, in the study of the analyzed water supply networks the concept of reliability in introduced. This concept is essential to understand the validity of the obtained results. The second part, starting with values optimized for the probability of crossing and mutation, the influence of the population size is analyzed in the final solutions on the network of Hanoi, widely studied in the bibliography. The aim is to find the most suitable configuration of the problem, so that good solutions are obtained in the less time.

  16. Sensitive Topics, Missing Data, and Refusal in Social Network Studies: An Ethical Examination.

    Science.gov (United States)

    Ellison, Erin Rose; Langhout, Regina Day

    2017-12-01

    We describe our ethics-driven process of addressing missing data within a social network study about accountability for racism, classism, sexism, heterosexism, cis-sexism, ableism, and other forms of oppression among social justice union organizers. During data collection, some would-be participants did not return emails and others explicitly refused to engage in the research. All refusals came from women of color. We faced an ethical dilemma: Should we continue to seek participation from those who had not yet responded, with the hopes of recruiting more women of color from within the network so their perspectives would not be tokenized? Or, should we stop asking those who had been contacted multiple times, which would compromise the social network data and analysis? We delineate ways in which current discussions of the ethics of social network studies fell short, given our framework and our community psychology (CP) values. We outline literature that was helpful in thinking through this challenge; we looked outside of CP to the decolonization literature on refusal. Lessons learned include listening for the possible meanings of refusals and considering the level of engagement and the labor required of participants when designing research studies. © Society for Community Research and Action 2017.

  17. Effects of meditation experience on functional connectivity of distributed brain networks

    Directory of Open Access Journals (Sweden)

    Wendy eHasenkamp

    2012-03-01

    Full Text Available This study sought to examine the effect of meditation experience on brain networks underlying cognitive actions employed during contemplative practice. In a previous study, we proposed a basic model of naturalistic cognitive fluctuations that occur during the practice of focused attention meditation. This model specifies four intervals in a cognitive cycle: mind wandering, awareness of mind wandering, shifting of attention, and sustained attention. Using subjective input from experienced practitioners during meditation, we identified activity in salience network regions during awareness of mind wandering and executive network regions during shifting and sustained attention. Brain regions associated with the default mode were active during mind wandering. In the present study, we reasoned that repeated activation of attentional brain networks over years of practice may induce lasting functional connectivity changes within relevant circuits. To investigate this possibility, we created seeds representing the networks that were active during the four phases of the earlier study, and examined functional connectivity during the resting state in the same participants. Connectivity maps were then contrasted between participants with high vs. low meditation experience. Participants with more meditation experience exhibited increased connectivity within attentional networks, as well as between attentional regions and medial frontal regions. These neural relationships may be involved in the development of cognitive skills, such as maintaining attention and disengaging from distraction, that are often reported with meditation practice. Furthermore, because altered connectivity of brain regions in experienced meditators was observed in a non-meditative (resting state, this may represent a transference of cognitive abilities off the cushion into daily life.

  18. High-accuracy local positioning network for the alignment of the Mu2e experiment.

    Energy Technology Data Exchange (ETDEWEB)

    Hejdukova, Jana B. [Czech Technical Univ., Prague (Czech Republic)

    2017-06-01

    This Diploma thesis describes the establishment of a high-precision local positioning network and accelerator alignment for the Mu2e physics experiment. The process of establishing new network consists of few steps: design of the network, pre-analysis, installation works, measurements of the network and making adjustments. Adjustments were performed using two approaches. First is a geodetic approach of taking into account the Earth’s curvature and the metrological approach of a pure 3D Cartesian system on the other side. The comparison of those two approaches is performed and evaluated in the results and compared with expected differences. The effect of the Earth’s curvature was found to be significant for this kind of network and should not be neglected. The measurements were obtained with Absolute Tracker AT401, leveling instrument Leica DNA03 and gyrotheodolite DMT Gyromat 2000. The coordinates of the points of the reference network were determined by the Least Square Meth od and the overall view is attached as Annexes.

  19. A fast and efficient gene-network reconstruction method from multiple over-expression experiments

    Directory of Open Access Journals (Sweden)

    Thurner Stefan

    2009-08-01

    Full Text Available Abstract Background Reverse engineering of gene regulatory networks presents one of the big challenges in systems biology. Gene regulatory networks are usually inferred from a set of single-gene over-expressions and/or knockout experiments. Functional relationships between genes are retrieved either from the steady state gene expressions or from respective time series. Results We present a novel algorithm for gene network reconstruction on the basis of steady-state gene-chip data from over-expression experiments. The algorithm is based on a straight forward solution of a linear gene-dynamics equation, where experimental data is fed in as a first predictor for the solution. We compare the algorithm's performance with the NIR algorithm, both on the well known E. coli experimental data and on in-silico experiments. Conclusion We show superiority of the proposed algorithm in the number of correctly reconstructed links and discuss computational time and robustness. The proposed algorithm is not limited by combinatorial explosion problems and can be used in principle for large networks.

  20. Azimuthally Sensitive Hanbury Brown–Twiss Interferometry measured with the ALICE Experiment

    CERN Document Server

    Gramling, Johanna

    Bose–Einstein correlations of identical pions emitted in high-energy particle collisions provide information about the size of the source region in space-time. If analyzed via HBT Interferometry in several directions with respect to the reaction plane, the shape of the source can be extracted. Hence, HBT Interferometry provides an excellent tool to probe the characteristics of the quark-gluon plasma possibly created in high-energy heavy-ion collisions. This thesis introduces the main theoretical concepts of particle physics, the quark-gluon plasma and the technique of HBT interferometry. The ALICE experiment at the CERN Large Hadron Collider (LHC) is explained and the first azimuthally integrated results measured in Pb–Pb collisions at sqrt(s_NN) = 2.76TeV with ALICE are presented. A detailed two-track resolution study leading to a global pair cut for HBT analyses has been performed, and a framework for the event plane determination has been developed. The results from azimuthally sensitive HBT interferom...

  1. On the Juno Radio Science Experiment: models, algorithms and sensitivity analysis

    CERN Document Server

    Tommei, Giacomo; Serra, Daniele; Milani, Andrea

    2014-01-01

    Juno is a NASA mission launched in 2011 with the goal of studying Jupiter. The probe will arrive to the planet in 2016 and will be placed for one year in a polar high-eccentric orbit to study the composition of the planet, the gravity and the magnetic field. The Italian Space Agency (ASI) provided the radio science instrument KaT (Ka-Band Translator) used for the gravity experiment, which has the goal of studying the Jupiter's deep structure by mapping the planet's gravity: such instrument takes advantage of synergies with a similar tool in development for BepiColombo, the ESA cornerstone mission to Mercury. The Celestial Mechanics Group of the University of Pisa, being part of the Juno Italian team, is developing an orbit determination and parameters estimation software for processing the real data independently from NASA software ODP. This paper has a twofold goal: first, to tell about the development of this software highlighting the models used, second, to perform a sensitivity analysis on the parameters ...

  2. Azimuthally sensitive Hanbury Brown-Twiss interferometry measured with the ALICE experiment

    Energy Technology Data Exchange (ETDEWEB)

    Gramling, Johanna Lena

    2011-07-01

    Bose-Einstein correlations of identical pions emitted in high-energy particle collisions provide information about the size of the source region in space-time. If analyzed via HBT Interferometry in several directions with respect to the reaction plane, the shape of the source can be extracted. Hence, HBT Interferometry provides an excellent tool to probe the characteristics of the quark-gluon plasma possibly created in high-energy heavy-ion collisions. This thesis introduces the main theoretical concepts of particle physics, the quark gluon plasma and the technique of HBT interferometry. The ALICE experiment at the CERN Large Hadron Collider (LHC) is explained and the first azimuthallyintegrated results measured in Pb-Pb collisions at √(s{sub NN})=2.76 TeV with ALICE are presented. A detailed two-track resolution study leading to a global pair cut for HBT analyses has been performed, and a framework for the event plane determination has been developed. The results from azimuthally sensitive HBT interferometry are compared to theoretical models and previous measurements at lower energies. Oscillations of the transverse radii in dependence on the pair emission angle are observed, consistent with a source that is extended out-of-plane.

  3. Factors associated with p-phenylenediamine sensitization: data from the Information Network of Departments of Dermatology, 2008-2013.

    Science.gov (United States)

    Schubert, Steffen; Lessmann, Holger; Schnuch, Axel; Uter, Wolfgang; Geier, Johannes

    2018-01-11

    Risk factors for p-phenylenediamine (PPD) sensitization include the use of hair dyes, the application of temporary black henna tattoos, working as a hairdresser, and, possibly, exposure to hair dye pretests. To quantify the impact of these (putative) risk factors on PPD sensitization. Six items related to PPD exposure were added to the routine Information Network of Departments of Dermatology questionnaire from 2008 to 2013. A retrospective analysis of data from 4314 patients tested with PPD 1% pet. was conducted. Of the PPD-positive patients (n = 271), 80% had their hair dyed, and, of these, 57% subsequently developed scalp dermatitis, whereas only 11% had had a henna tattoo. The self-administrated pretest with hair dye was performed by only a few patients, precluding a more detailed analysis. Hair dyeing [odds ratio (OR) 6.0; 95% confidence interval (CI): 3.9-9.4], henna tattoos (OR 2.4; 95%CI: 1.5-3.7) and being a hairdresser (OR 2.1; 95%CI: 1.3-3.2) increased the risk of PPD sensitization. Neither dyeing of own hair nor application of a temporary henna tattoo seemed to affect PPD sensitization in hairdressers. p-Aminoaryl compounds more often gave positive reactions in patients with henna tattoo. Hair dyeing is the major risk factor for PPD sensitization in this clinical setting, and application of a temporary black henna tattoo may also lead to (strong) PPD sensitization. © 2018 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  4. The Influential Factors for the Variation of Data Sensitivity in Ubiquitous Social Networking

    DEFF Research Database (Denmark)

    Sapuppo, Antonio

    2013-01-01

    sensitivity is decreasing inversely proportionally to the relevance of data disclosure for initiation of relationships with others. We suggest privacy designers should take into account the purpose of disclosure and environment as primary indexes for data disclosure. Other influential factors, i.e. activity......, mood, location familiarity, number of previous encounters and mutual friends, were also discovered to influence participants' data disclosure, but as factors of secondary importance....... to crucial privacy threats. In order to contribute to the design of privacy management systems, we present results of a mixed methods study that investigated the influential factors for the variation of human data sensitivity upon different circumstances. The results indicate that the users' information...

  5. EDITORIAL Wireless sensor networks: design for real-life deployment and deployment experiences Wireless sensor networks: design for real-life deployment and deployment experiences

    Science.gov (United States)

    Gaura, Elena; Roedig, Utz; Brusey, James

    2010-12-01

    modalities and (iv) system solutions with high end-user added value and cost benefits. The common thread is deployment and deployment evaluation. In particular, satisfaction of application requirements, involvement of the end-user in the design and deployment process, satisfactory system performance and user acceptance are concerns addressed in many of the contributions. The contributions form a valuable set, which help to identify the priorities for research in this burgeoning area: Robust, reliable and efficient data collection in embedded wireless multi-hop networks are essential elements in creating a true deploy-and-forget user experience. Maintaining full connectivity within a WSN, in a real world environment populated by other WSNs, WiFi networks or Bluetooth devices that constitute sources of interference is a key element in any application, but more so for those that are safety-critical, such as disaster response. Awareness of the effects of wireless channel, physical position and line-of-sight on received signal strength in real-world, outdoor environments will shape the design of many outdoor applications. Thus, the quantification of such effects is valuable knowledge for designers. Sensors' failure detection, scalability and commercialization are common challenges in many long-term monitoring applications; transferable solutions are evidenced here in the context of pollutant detection and water quality. Innovative, alternative thinking is often needed to achieve the desired long-lived networks when power-hungry sensors are foreseen components; in some instances, the very problems of wireless technology, such as RF irregularity, can be transformed into advantages. The importance of an iterative design and evaluation methodology—from analysis to simulation to real-life deployment—should be well understood by all WSN developers. The value of this is highlighted in the context of a challenging WPAN video-surveillance application based on a novel Nomadic Access

  6. Phenotypic plasticity in Drosophila pigmentation caused by temperature sensitivity of a chromatin regulator network.

    Directory of Open Access Journals (Sweden)

    Jean-Michel Gibert

    2007-02-01

    Full Text Available Phenotypic plasticity is the ability of a genotype to produce contrasting phenotypes in different environments. Although many examples have been described, the responsible mechanisms are poorly understood. In particular, it is not clear how phenotypic plasticity is related to buffering, the maintenance of a constant phenotype against genetic or environmental variation. We investigate here the genetic basis of a particularly well described plastic phenotype: the abdominal pigmentation in female Drosophila melanogaster. Cold temperature induces a dark pigmentation, in particular in posterior segments, while higher temperature has the opposite effect. We show that the homeotic gene Abdominal-B (Abd-B has a major role in the plasticity of pigmentation in the abdomen. Abd-B plays opposite roles on melanin production through the regulation of several pigmentation enzymes. This makes the control of pigmentation very unstable in the posterior abdomen, and we show that the relative spatio-temporal expression of limiting pigmentation enzymes in this region of the body is thermosensitive. Temperature acts on melanin production by modulating a chromatin regulator network, interacting genetically with the transcription factor bric-à-brac (bab, a target of Abd-B and Hsp83, encoding the chaperone Hsp90. Genetic disruption of this chromatin regulator network increases the effect of temperature and the instability of the pigmentation pattern in the posterior abdomen. Colocalizations on polytene chromosomes suggest that BAB and these chromatin regulators cooperate in the regulation of many targets, including several pigmentation enzymes. We show that they are also involved in sex comb development in males and that genetic destabilization of this network is also strongly modulated by temperature for this phenotype. Thus, we propose that phenotypic plasticity of pigmentation is a side effect reflecting a global impact of temperature on epigenetic mechanisms

  7. Defining Biological Networks for Noise Buffering and Signaling Sensitivity Using Approximate Bayesian Computation

    Directory of Open Access Journals (Sweden)

    Shuqiang Wang

    2014-01-01

    Full Text Available Reliable information processing in cells requires high sensitivity to changes in the input signal but low sensitivity to random fluctuations in the transmitted signal. There are often many alternative biological circuits qualifying for this biological function. Distinguishing theses biological models and finding the most suitable one are essential, as such model ranking, by experimental evidence, will help to judge the support of the working hypotheses forming each model. Here, we employ the approximate Bayesian computation (ABC method based on sequential Monte Carlo (SMC to search for biological circuits that can maintain signaling sensitivity while minimizing noise propagation, focusing on cases where the noise is characterized by rapid fluctuations. By systematically analyzing three-component circuits, we rank these biological circuits and identify three-basic-biological-motif buffering noise while maintaining sensitivity to long-term changes in input signals. We discuss in detail a particular implementation in control of nutrient homeostasis in yeast. The principal component analysis of the posterior provides insight into the nature of the reaction between nodes.

  8. Location Sensitive Deep Convolutional Neural Networks for Segmentation of White Matter Hyperintensities.

    Science.gov (United States)

    Ghafoorian, Mohsen; Karssemeijer, Nico; Heskes, Tom; van Uden, Inge W M; Sanchez, Clara I; Litjens, Geert; de Leeuw, Frank-Erik; van Ginneken, Bram; Marchiori, Elena; Platel, Bram

    2017-07-11

    The anatomical location of imaging features is of crucial importance for accurate diagnosis in many medical tasks. Convolutional neural networks (CNN) have had huge successes in computer vision, but they lack the natural ability to incorporate the anatomical location in their decision making process, hindering success in some medical image analysis tasks. In this paper, to integrate the anatomical location information into the network, we propose several deep CNN architectures that consider multi-scale patches or take explicit location features while training. We apply and compare the proposed architectures for segmentation of white matter hyperintensities in brain MR images on a large dataset. As a result, we observe that the CNNs that incorporate location information substantially outperform a conventional segmentation method with handcrafted features as well as CNNs that do not integrate location information. On a test set of 50 scans, the best configuration of our networks obtained a Dice score of 0.792, compared to 0.805 for an independent human observer. Performance levels of the machine and the independent human observer were not statistically significantly different (p-value = 0.06).

  9. SBMLsqueezer 2: context-sensitive creation of kinetic equations in biochemical networks.

    Science.gov (United States)

    Dräger, Andreas; Zielinski, Daniel C; Keller, Roland; Rall, Matthias; Eichner, Johannes; Palsson, Bernhard O; Zell, Andreas

    2015-10-09

    The size and complexity of published biochemical network reconstructions are steadily increasing, expanding the potential scale of derived computational models. However, the construction of large biochemical network models is a laborious and error-prone task. Automated methods have simplified the network reconstruction process, but building kinetic models for these systems is still a manually intensive task. Appropriate kinetic equations, based upon reaction rate laws, must be constructed and parameterized for each reaction. The complex test-and-evaluation cycles that can be involved during kinetic model construction would thus benefit from automated methods for rate law assignment. We present a high-throughput algorithm to automatically suggest and create suitable rate laws based upon reaction type according to several criteria. The criteria for choices made by the algorithm can be influenced in order to assign the desired type of rate law to each reaction. This algorithm is implemented in the software package SBMLsqueezer 2. In addition, this program contains an integrated connection to the kinetics database SABIO-RK to obtain experimentally-derived rate laws when desired. The described approach fills a heretofore absent niche in workflows for large-scale biochemical kinetic model construction. In several applications the algorithm has already been demonstrated to be useful and scalable. SBMLsqueezer is platform independent and can be used as a stand-alone package, as an integrated plugin, or through a web interface, enabling flexible solutions and use-case scenarios.

  10. Fault Tolerant Ethernet Based Network for Time Sensitive Applications in Electrical Power Distribution Systems

    Directory of Open Access Journals (Sweden)

    Leos Bohac

    2013-01-01

    Full Text Available The paper analyses and experimentally verifies deployment of Ethernet based network technology to enable fault tolerant and timely exchange of data among a number of high voltage protective relays that use proprietary serial communication line to exchange data in real time on a state of its high voltage circuitry facilitating a fast protection switching in case of critical failures. The digital serial signal is first fetched into PCM multiplexer where it is mapped to the corresponding E1 (2 Mbit/s time division multiplexed signal. Subsequently, the resulting E1 frames are then packetized and sent through Ethernet control LAN to the opposite PCM demultiplexer where the same but reverse processing is done finally sending a signal into the opposite protective relay. The challenge of this setup is to assure very timely delivery of the control information between protective relays even in the cases of potential failures of Ethernet network itself. The tolerance of Ethernet network to faults is assured using widespread per VLAN Rapid Spanning Tree Protocol potentially extended by 1+1 PCM protection as a valuable option.

  11. A drug-sensitive genetic network masks fungi from the immune system.

    Directory of Open Access Journals (Sweden)

    2006-04-01

    Full Text Available Fungal pathogens can be recognized by the immune system via their beta-glucan, a potent proinflammatory molecule that is present at high levels but is predominantly buried beneath a mannoprotein coat and invisible to the host. To investigate the nature and significance of "masking" this molecule, we characterized the mechanism of masking and consequences of unmasking for immune recognition. We found that the underlying beta-glucan in the cell wall of Candida albicans is unmasked by subinhibitory doses of the antifungal drug caspofungin, causing the exposed fungi to elicit a stronger immune response. Using a library of bakers' yeast (Saccharomyces cerevisiae mutants, we uncovered a conserved genetic network that is required for concealing beta-glucan from the immune system and limiting the host response. Perturbation of parts of this network in the pathogen C. albicans caused unmasking of its beta-glucan, leading to increased beta-glucan receptor-dependent elicitation of key proinflammatory cytokines from primary mouse macrophages. By creating an anti-inflammatory barrier to mask beta-glucan, opportunistic fungi may promote commensal colonization and have an increased propensity for causing disease. Targeting the widely conserved gene network required for creating and maintaining this barrier may lead to novel broad-spectrum antimycotics.

  12. Discriminating between rival biochemical network models: three approaches to optimal experiment design

    Directory of Open Access Journals (Sweden)

    August Elias

    2010-04-01

    Full Text Available Abstract Background The success of molecular systems biology hinges on the ability to use computational models to design predictive experiments, and ultimately unravel underlying biological mechanisms. A problem commonly encountered in the computational modelling of biological networks is that alternative, structurally different models of similar complexity fit a set of experimental data equally well. In this case, more than one molecular mechanism can explain available data. In order to rule out the incorrect mechanisms, one needs to invalidate incorrect models. At this point, new experiments maximizing the difference between the measured values of alternative models should be proposed and conducted. Such experiments should be optimally designed to produce data that are most likely to invalidate incorrect model structures. Results In this paper we develop methodologies for the optimal design of experiments with the aim of discriminating between different mathematical models of the same biological system. The first approach determines the 'best' initial condition that maximizes the L2 (energy distance between the outputs of the rival models. In the second approach, we maximize the L2-distance of the outputs by designing the optimal external stimulus (input profile of unit L2-norm. Our third method uses optimized structural changes (corresponding, for example, to parameter value changes reflecting gene knock-outs to achieve the same goal. The numerical implementation of each method is considered in an example, signal processing in starving Dictyostelium amœbæ. Conclusions Model-based design of experiments improves both the reliability and the efficiency of biochemical network model discrimination. This opens the way to model invalidation, which can be used to perfect our understanding of biochemical networks. Our general problem formulation together with the three proposed experiment design methods give the practitioner new tools for a systems

  13. A State-Based Sensitivity Analysis for Distinguishing the Global Importance of Predictor Variables in Artificial Neural Networks

    Directory of Open Access Journals (Sweden)

    Ehsan Ardjmand

    2016-01-01

    Full Text Available Artificial neural networks (ANNs are powerful empirical approaches used to model databases with a high degree of accuracy. Despite their recognition as universal approximators, many practitioners are skeptical about adopting their routine usage due to lack of model transparency. To improve the clarity of model prediction and correct the apparent lack of comprehension, researchers have utilized a variety of methodologies to extract the underlying variable relationships within ANNs, such as sensitivity analysis (SA. The theoretical basis of local SA (that predictors are independent and inputs other than variable of interest remain “fixed” at predefined values is challenged in global SA, where, in addition to altering the attribute of interest, the remaining predictors are varied concurrently across their respective ranges. Here, a regression-based global methodology, state-based sensitivity analysis (SBSA, is proposed for measuring the importance of predictor variables upon a modeled response within ANNs. SBSA was applied to network models of a synthetic database having a defined structure and exhibiting multicollinearity. SBSA achieved the most accurate portrayal of predictor-response relationships (compared to local SA and Connected Weights Analysis, closely approximating the actual variability of the modeled system. From this, it is anticipated that skepticisms concerning the delineation of predictor influences and their uncertainty domains upon a modeled output within ANNs will be curtailed.

  14. Lost in the city: revisiting Milgram's experiment in the age of social networks.

    Directory of Open Access Journals (Sweden)

    János Szüle

    Full Text Available As more and more users access social network services from smart devices with GPS receivers, the available amount of geo-tagged information makes repeating classical experiments possible on global scales and with unprecedented precision. Inspired by the original experiments of Milgram, we simulated message routing within a representative sub-graph of the network of Twitter users with about 6 million geo-located nodes and 122 million edges. We picked pairs of users from two distant metropolitan areas and tried to find a route between them using local geographic information only; our method was to forward messages to a friend living closest to the target. We found that the examined network is navigable on large scales, but navigability breaks down at the city scale and the network becomes unnavigable on intra-city distances. This means that messages usually arrived to the close proximity of the target in only 3-6 steps, but only in about 20% of the cases was it possible to find a route all the way to the recipient, in spite of the network being connected. This phenomenon is supported by the distribution of link lengths; on larger scales the distribution behaves approximately as P(d ≈ 1/d, which was found earlier by Kleinberg to allow efficient navigation, while on smaller scales, a fractal structure becomes apparent. The intra-city correlation dimension of the network was found to be D2 = 1.25, less than the dimension D2 = 1.78 of the distribution of the population.

  15. An artificial neural network based $b$ jet identification algorithm at the CDF Experiment

    CERN Document Server

    Freeman, J; Ketchum, W; Poprocki, S; Pronko, A; Rusu, V; Wittich, P

    2011-01-01

    We present the development and validation of a new multivariate $b$ jet identification algorithm ("$b$ tagger") used at the CDF experiment at the Fermilab Tevatron. At collider experiments, $b$ taggers allow one to distinguish particle jets containing $B$ hadrons from other jets. Employing feed-forward neural network architectures, this tagger is unique in its emphasis on using information from individual tracks. This tagger not only contains the usual advantages of a multivariate technique such as maximal use of information in a jet and tunable purity/efficiency operating points, but is also capable of evaluating jets with only a single track. To demonstrate the effectiveness of the tagger, we employ a novel method wherein we calculate the false tag rate and tag efficiency as a function of the placement of a lower threshold on a jet's neural network output value in $Z+1$ jet and $t\\bar{t}$ candidate samples, rich in light flavor and $b$ jets, respectively.

  16. Residential Preferences for River Network Improvement: An Exploration of Choice Experiments in Zhujiajiao, Shanghai, China

    Science.gov (United States)

    Che, Yue; Li, Wen; Shang, Zhaoyi; Liu, Chen; Yang, Kai

    2014-09-01

    River networks have both ecological and social benefits for urban development. However, river networks have suffered extensive destruction as a result of urbanization and industrialization, especially in China. River restoration is a growth business but suffers poor efficiency due to a lack of social understanding. Assessing the benefits of river system restoration and recognizing public preferences are critical for effective river ecosystem restoration and sustainable river management. This study used a choice experiment with a multinomial logit model and a random parameter logit model to assess respondents' cognitive preferences regarding attributes of river networks, and their possible sources of heterogeneity. Results showed that riverfront condition was the attribute most preferred by respondents, while stream morphology was the least preferred. Results also illustrated that the current status of each of three river network attributes was not desirable, and respondents would prefer a river network with a "branch pattern," that is "limpid with no odor," and "accessible with vegetation." Estimated willingness to pay was mainly affected by household monthly income, residential location, and whether respondents had household members engaged in a water protection career. The assessment results can provide guidance and a reference for managers, sponsors, and researchers.

  17. Inactivation of mechano-sensitive dilatation upon repetitive mechanical stimulation of the musculo-vascular network in the rabbit.

    Science.gov (United States)

    Turturici, M; Roatta, S

    2013-06-01

    Mechano-sensitivity of the vascular network is known to be implicated in the rapid dilatation at the onset of exercise, however, it is not known how this mechanism responds to repetitive mechanical stimulation. This study tests the hypothesis that the mechanically-induced hyperaemia undergoes some attenuation upon repetitive stimulation. Muscle blood flow was recorded from 9 masseteric arteries (5 right, 4 left) in 6 anesthetized rabbits. Two mechanical stimuli, masseter muscle compression (MC) and occlusion of the masseteric artery (AO), were provided in different combinations: A) repeated stimulation (0.5 Hz, for 40 s); B) single stimuli delivered at decreasing inter-stimulus interval (ISI) from 4 min to 2 s, C) single AO delivered before and immediately after a series of 20 MCs at 0.5 Hz, and vice-versa. Repetitive AO stimulation at 0.5 Hz produced a transient hyperaemia (378 ±189%) peaking at 4.5 ±1.4 s and then decaying before the end of stimulation. The hyperaemic response to individual AOs progressively decreased by 74 ±39% with decreasing ISI from 4 min to 2 s (p<0.01). Non significant differences were observed between AO and MC stimulation. Decreased response to AO was also provoked by previous repetitive MC stimulation, and vice-versa. The results provide evidence that the mechano-sensitivity of the vascular network is attenuated by previous mechanical stimulation. It is suggested that the mechano-sensitive dilatory mechanisms undergoes some inactivation whose recovery time is in the order of a few minutes.

  18. A FPGA-based Network Interface Card with GPUDirect enabling realtime GPU computing in HEP experiments

    OpenAIRE

    Lonardo, Alessandro; Ameli, Fabrizio; Ammendola, Roberto; Biagioni, Andrea; Cotta Ramusino, Angelo; Fiorini, Massimiliano; Frezza, Ottorino; Lamanna, Gianluca; Lo Cicero, Francesca; Martinelli, Michele; Neri, Ilaria; Paolucci, Pier Stanislao; Pastorelli, Elena; Pontisso, Luca; Rossetti, Davide

    2015-01-01

    The capability of processing high bandwidth data streams in real-time is a computational requirement common to many High Energy Physics experiments. Keeping the latency of the data transport tasks under control is essential in order to meet this requirement. We present NaNet, a FPGA-based PCIe Network Interface Card design featuring Remote Direct Memory Access towards CPU and GPU memories plus a transport protocol offload module characterized by cycle-accurate upper-bound handling. The combin...

  19. Search for Single Top Quark Production at the D0 Experiment using Bayesian Neural Networks

    CERN Document Server

    Tanasijczuk, Andres J

    2009-01-01

    We present the methodology used to measure the single top quark production cross section in the D0 experiment, and show as an example the results that led to the first evidence of single top quark production in D0 at the Fermilab Tevatron proton-antiproton collider. The selected events are mostly backgrounds, which we separate from the expected signals using three multivariate analysis techniques, one of them being Bayesian neural networks, which we will describe here.

  20. The neural correlates of reciprocity are sensitive to prior experience of reciprocity.

    Science.gov (United States)

    Cáceda, Ricardo; Prendes-Alvarez, Stefania; Hsu, Jung-Jiin; Tripathi, Shanti P; Kilts, Clint D; James, G Andrew

    2017-08-14

    Reciprocity is central to human relationships and is strongly influenced by multiple factors including the nature of social exchanges and their attendant emotional reactions. Despite recent advances in the field, the neural processes involved in this modulation of reciprocal behavior by ongoing social interaction are poorly understood. We hypothesized that activity within a discrete set of neural networks including a putative moral cognitive neural network is associated with reciprocity behavior. Nineteen healthy adults underwent functional magnetic resonance imaging scanning while playing the trustee role in the Trust Game. Personality traits and moral development were assessed. Independent component analysis was used to identify task-related functional brain networks and assess their relationship to behavior. The saliency network (insula and anterior cingulate) was positively correlated with reciprocity behavior. A consistent array of brain regions supports the engagement of emotional, self-referential and planning processes during social reciprocity behavior. Published by Elsevier B.V.

  1. Experience modulates both aromatase activity and the sensitivity of agonistic behaviour to testosterone in black-headed gulls

    NARCIS (Netherlands)

    Ros, Albert F. H.; Franco, Aldina M. A.; Groothuis, Ton G. G.

    2009-01-01

    In young black-headed gulls (Larus ridibundus), exposure to testosterone increases the sensitivity of agonistic behaviour to a subsequent exposure to this hormone. The aim of this paper is twofold: to analyze whether social experience, gained during testosterone exposure, mediates this increase in

  2. Signal Fluctuation Sensitivity: An Improved Metric for Optimizing Detection of Resting-State fMRI Networks

    Science.gov (United States)

    DeDora, Daniel J.; Nedic, Sanja; Katti, Pratha; Arnab, Shafique; Wald, Lawrence L.; Takahashi, Atsushi; Van Dijk, Koene R. A.; Strey, Helmut H.; Mujica-Parodi, Lilianne R.

    2016-01-01

    Task-free connectivity analyses have emerged as a powerful tool in functional neuroimaging. Because the cross-correlations that underlie connectivity measures are sensitive to distortion of time-series, here we used a novel dynamic phantom to provide a ground truth for dynamic fidelity between blood oxygen level dependent (BOLD)-like inputs and fMRI outputs. We found that the de facto quality-metric for task-free fMRI, temporal signal to noise ratio (tSNR), correlated inversely with dynamic fidelity; thus, studies optimized for tSNR actually produced time-series that showed the greatest distortion of signal dynamics. Instead, the phantom showed that dynamic fidelity is reasonably approximated by a measure that, unlike tSNR, dissociates signal dynamics from scanner artifact. We then tested this measure, signal fluctuation sensitivity (SFS), against human resting-state data. As predicted by the phantom, SFS—and not tSNR—is associated with enhanced sensitivity to both local and long-range connectivity within the brain's default mode network. PMID:27199643

  3. Ethical Sensitivity in Nursing Ethical Leadership: A Content Analysis of Iranian Nurses Experiences

    Science.gov (United States)

    Esmaelzadeh, Fatemeh; Abbaszadeh, Abbas; Borhani, Fariba; Peyrovi, Hamid

    2017-01-01

    Background: Considering that many nursing actions affect other people’s health and life, sensitivity to ethics in nursing practice is highly important to ethical leaders as a role model. Objective: The study aims to explore ethical sensitivity in ethical nursing leaders in Iran. Method: This was a qualitative study based on the conventional content analysis in 2015. Data were collected using deep and semi-structured interviews with 20 Iranian nurses. The participants were chosen using purposive sampling. Data were analyzed using conventional content analysis. In order to increase the accuracy and integrity of the data, Lincoln and Guba's criteria were considered. Results: Fourteen sub-categories and five main categories emerged. Main categories consisted of sensitivity to care, sensitivity to errors, sensitivity to communication, sensitivity in decision making and sensitivity to ethical practice. Conclusion: Ethical sensitivity appears to be a valuable attribute for ethical nurse leaders, having an important effect on various aspects of professional practice and help the development of ethics in nursing practice. PMID:28584564

  4. Comparative efficacy of antihypertensive agents in salt-sensitive hypertensive patients: a network meta-analysis.

    Science.gov (United States)

    Qi, Han; Liu, Zheng; Cao, Han; Sun, Wei-Ping; Peng, Wen-Juan; Liu, Bin; Dong, Sheng-Jie; Xiang, Yu-Tao; Zhang, Ling

    2018-02-09

    Salt-sensitive hypertension (SSH) is an intermediate inherited phenotype of essential hypertension as well as being an independent risk factor for cardiovascular disease. However, effective medications for the treatment of SSH have not been clarified. This study was to compare the efficacious of different classes of antihypertensive agents combined with salt intake on the reduction of blood pressure in patients with salt-sensitive hypertension (SSH). We used sources as PubMed, EMBASE, Cochrane Library, CENTRAL, ClinicalTrials.gov, ICTRP, CNKI and WANFANG database from inception to November 2016. Studies that compared the efficacy of two or more antihypertensive agents or placebos in adult salt-sensitive hypertensive patients were included. The outcomes included variations in mean arterial blood pressure, systolic and diastolic blood pressure. Twenty-five studies were involved in this meta-analysis. A CCB with hydrochlorothiazide and moderate salt intake was significantly the most efficacious in comparison with placebo [standardized mean differences (SMD), 95% credibility intervals (CI): 26.66, 12.60-40.16], ARBs [SMD, 95% CI: 22.94, 5.26-40.51] and the other interventions for patients with SSH and no concomitant diseases. For SSH patients who were obese, the effect size of CCB with metformin and moderate salt intake was [SMD, 95% CI: 17.90, 6.26 -29.33]. For SSH patients with no concomitant diseases, CCB combined with hydrochlorothiazide and moderate salt intake were optimal in reducing blood pressure, while CCB combined with metformin and moderate salt intake were the most efficacious at reducing blood pressure in SSH patients with coexisting obesity.

  5. Sensitivity analysis for CORSOR models simulating fission product release in LOFT-LP-FP-2 severe accident experiment

    Energy Technology Data Exchange (ETDEWEB)

    Hoseyni, Seyed Mohsen [Islamic Azad Univ., Tehran (Iran, Islamic Republic of). Dept. of Basic Sciences; Islamic Azad Univ., Tehran (Iran, Islamic Republic of). Young Researchers and Elite Club; Pourgol-Mohammad, Mohammad [Sahand Univ. of Technology, Tabriz (Iran, Islamic Republic of). Dept. of Mechanical Engineering; Yousefpour, Faramarz [Nuclear Science and Technology Research Institute, Tehran (Iran, Islamic Republic of)

    2017-03-15

    This paper deals with simulation, sensitivity and uncertainty analysis of LP-FP-2 experiment of LOFT test facility. The test facility simulates the major components and system response of a pressurized water reactor during a LOCA. MELCOR code is used for predicting the fission product release from the core fuel elements in LOFT LP-FP-2 experiment. Moreover, sensitivity and uncertainty analysis is performed for different CORSOR models simulating release of fission products in severe accident calculations for nuclear power plants. The calculated values for the fission product release are compared under different modeling options to the experimental data available from the experiment. In conclusion, the performance of 8 CORSOR modeling options is assessed for available modeling alternatives in the code structure.

  6. CONCERNING THE NETWORKING INTERACTION EXPERIENCE OF TEACHERS AND STUDENTS OF PEDAGOGICAL UNIVERSITY

    Directory of Open Access Journals (Sweden)

    E. A. Dmitrieva

    2015-01-01

    Full Text Available The purpose of the research is to identify the possibilities for the formation knowledge and practical skills related to the use of the professional activity of software and network resource of teaching communities in the pedagogical sphere.Methods. The methods involve the analysis of the literary sources, regulatory documents, Internet resources within the researched problem; an analysis of the practical experience of teachers of secondary schools, work of high school teachers and establishment of training teachers on the research problem; the experimental work and monitoring the learning process.Results. The process of teachers’ training inYaroslavl, in particular preparation of students-biologists at theYaroslavlStatePedagogicalUniversityis reflected. Activity of network pedagogical community of Yaroslavl is considered as a platform for network interaction; the analysis of such platform, use of its resources, and also conversations with subject teachers and students have shown that the given electronic and communication resources cause a great interest for practicing teachers and future experts, however, they not always possess necessary knowledge and abilities concerning its operation.Scientific novelty. The author describes in detail the process of forming a competence of networking of professional interaction in terms of its methodological support that is relevant to the educational process, both in the high school, and post-graduate education.Practical significance. The research implementations can be useful while developing specific guidelines to explain the content and methodology of the training network of professional interaction with examples of practicing teachers and students ofPedagogicalUniversity– future teachers of biology.The article is addressed to researchers, dealing with networking, specialists of teaching service centers (institutions of educational development, the practicing subject teachers and teachers of high

  7. Sensitivity of the High Altitude Water Cherenkov Experiment to observe Gamma-Ray Bursts

    Science.gov (United States)

    González, M. M.

    Ground based telescopes have marginally observed very high energy emission (>100GeV) from gamma-ray bursts(GRB). For instance, Milagrito observed GRB970417a with a significance of 3.7 sigmas over the background. Milagro have not yet observed TeV emission from a GRB with its triggered and untriggered searches or GeV emission with a triggered search using its scalers. These results suggest the need of new observatories with higher sensitivity to transient sources. The HAWC (High Altitute Water Cherenkov) observatory is proposed as a combination of the Milagro tecnology with a very high altitude (>4000m over see level) site. The expected HAWC sensitivity for GRBs is at least >10 times the Milagro sensitivity. In this work HAWC sensitivity for GRBs is discussed for different detector configurations such as altitude, distance between PMTs, depth under water of PMTs, number of PMTs required for a trigger, etc.

  8. Building a Governance Strategy for CER: The Patient Outcomes Research to Advance Learning (PORTAL) Network Experience.

    Science.gov (United States)

    Paolino, Andrea R; McGlynn, Elizabeth A; Lieu, Tracy; Nelson, Andrew F; Prausnitz, Stephanie; Horberg, Michael A; Arterburn, David E; Gould, Michael K; Laws, Reesa L; Steiner, John F

    2016-01-01

    for adaptation by other networks. As a result of identifying project-based governance priorities (IRB approval, subcontracting, selection of new research including lead PI and participating sites, and authorship) and data governance priorities (reciprocal data use agreement, analytic plan procedures, and other tools for data governance), PORTAL established most of its governance structure by Month 6 of the 18 month project. This allowed science to progress and collaborators to experience first-hand how the structures and procedures functioned in the remaining 12 months of the project, leaving ample time to refine them and to develop new structures or processes as necessary. The use of procedures and processes with which participating investigators and their home institutions were already familiar allowed project and regulatory requirements to be established quickly to protect patients, their data, and the health care systems that act as stewards for both. As the project progressed, PORTAL was able to test and adjust the structures it put place, and to make substantive revisions by Month 17. As a result, priority processes have been predictable, transparent and effective. Strong governance practices are a stewardship responsibility of research networks to justify the trust of patients, health plan members, health care delivery organizations, and other stakeholders. Well-planned governance can reduce the time necessary to initiate the scientific activities of a network, a particular concern when the time frame to complete research is short. Effective network and data governance structures protect patient and institutional data as well as the interests of investigators and their institutions, and assures that the network has built an environment to meet the goals of the research.

  9. Desensitization protocol for highly sensitized renal transplant patients: A single-center experience

    OpenAIRE

    Kute, Vivek B.; Vanikar, Aruna V.; Trivedi, Hargovind L; Shah, Pankaj R; Kamal R Goplani; Patel, Himanshu V.; Gumber, Manoj R.; Patel, Rashmi D; Kamal V Kanodia; Kamlesh S Suthar; Trivedi, Varsha B; Pranjal R Modi

    2011-01-01

    Highly sensitized patients are destined to remain untransplanted for long. Early transplantation results in cost-saving, reduced morbidity/mortality and improved quality of life. We carried out a prospective study to evaluate the efficacy and safety of desensitization protocol vis-à-vis patient/graft survival in living donor renal transplantation in highly sensitized patients. Between December 2008 and April 2010, 34 renal transplant (RTx) patients underwent desensitization protocol. An anti-...

  10. A new luminescent lanthanide supramolecular network possessing free Lewis base sites for highly selective and sensitive Cu(2+) sensing.

    Science.gov (United States)

    Chu, Tianshu; Hu, Yunsong; Wu, Jinlun; Zeng, Chenghui; Yang, Yangyi; Ng, Seik Weng

    2016-06-08

    A series of new lanthanide complexes, formulated as [Ln2(DCSAL)3(H2O)11]·3DCSAL·4H2O [Ln = Eu (1), Gd (2) and Tb (3); DCSAL = 3,5-dichlorosalicylate], have been synthesized and characterized by single crystal X-ray analysis. They are dinuclear clusters and form a 3D supramolecular network viaπ-π stacking and halogen bonding interactions. 3 exhibits strong Tb characteristic emission, whose quantum yield is as high as 38%. Due to binding with Cu(2+) ions via its Lewis acid-base interactions, 3 displayed a high selectivity and sensitivity for Cu(2+) detection based on Tb(3+) emission quenching. The possible quenching mechanism was further proved to be a static quenching mechanism by Stern-Volmer plots and UV-vis spectrum. More importantly, the binding constant between 3 and Cu(2+) is also calculated by the Benesi-Hildebrand method, which is helpful for quantitative analysis.

  11. Delay-sensitive content distribution via peer-to-peer collaboration in public safety vehicular ad-hoc networks

    KAUST Repository

    Atat, Rachad

    2014-05-01

    Delay-sensitive content distribution with peer-to-peer (P2P) cooperation in public safety vehicular networks is investigated. Two cooperative schemes are presented and analyzed. The first scheme is based on unicasting from the base station, whereas the second is based on threshold based multicasting. Long Term Evolution (LTE) is used for long range (LR) communications with the base station (BS) and IEEE 802.11p is considered for inter-vehicle collaboration on the short range (SR). The first scheme is shown to outperform non-cooperative unicasting and multicasting, while the second scheme outperforms non-cooperative unicasting beyond a specific number of cooperating vehicles, when the appropriate 802.11p power class is used. The first scheme achieves the best performance among the compared methods, and a practical approximation of that scheme is shown to be close to optimal performance. © 2014 Elsevier B.V. All rights reserved.

  12. Orientation tuning of motion-sensitive neurons shaped by vertical-horizontal network interactions.

    Science.gov (United States)

    Haag, J; Borst, A

    2003-05-01

    We measured the orientation tuning of two neurons of the fly lobula plate (H1 and H2 cells) sensitive to horizontal image motion. Our results show that H1 and H2 cells are sensitive to vertical motion, too. Their response depended on the position of the vertically moving stimuli within their receptive field. Stimulation within the frontal receptive field produced an asymmetric response: upward motion left the H1/H2 spike frequency nearly unaltered while downward motion increased the spike frequency to about 40% of their maximum responses to horizontal motion. In the lateral parts of their receptive fields, no such asymmetry in the responses to vertical image motion was found. Since downward motion is known to be the preferred direction of neurons of the vertical system in the lobula plate, we analyzed possible interactions between vertical system cells and H1 and H2 cells. Depolarizing current injection into the most frontal vertical system cell (VS1) led to an increased spike frequency, hyperpolarizing current injection to a decreased spike frequency in both H1 and H2 cells. Apart from VS1, no other vertical system cell (VS2-8) had any detectable influence on either H1 or H2 cells. The connectivity of VS1 and H1/H2 is also shown to influence the response properties of both centrifugal horizontal cells in the contralateral lobula plate, which are known to be postsynaptic to the H1 and H2 cells. The vCH cell receives additional input from the contralateral VS2-3 cells via the spiking interneuron V1.

  13. Two Years Experience With A Broadband Cable Network In An 1100-Bed Hospital

    Science.gov (United States)

    Cahill, Patrick T.; McCarthy, Robert H.; James, R.; Knowles, R.

    1985-09-01

    Early in 1983, a three-cable broadband network was installed in The New York Hospital-Cornell Medical Center using well-established cable-TV technology. This network was configured in a vertical tree topology. Currently, it extends over thirteen floors vertically and over two city blocks horizontally. It has now survived several major renovations on the various floors of the hospital. This survivability is a result of the siting of the main tree and of the isolation gained for the branches through the strategic placement of amplifiers. This communications system was designed in a modular fashion for later expansion and so that seven types of functions could be supported on the network without the addition of a new functional level disrupting the functions already existing on the system. Thus far, two functions (real-time image consultation and computer sharing) have been implemented, and two other functions (analog image storage and data base management) are in the prototype stage. Perhaps the most significant feature of our experience thus far has been the ease and utility of analog transmission and storage of images. This experience has lead us to postpone and even de-emphasize digital transmission and storage in our future plans.

  14. Functional connectivity in task-negative network of the Deaf: effects of sign language experience.

    Science.gov (United States)

    Malaia, Evie; Talavage, Thomas M; Wilbur, Ronnie B

    2014-01-01

    Prior studies investigating cortical processing in Deaf signers suggest that life-long experience with sign language and/or auditory deprivation may alter the brain's anatomical structure and the function of brain regions typically recruited for auditory processing (Emmorey et al., 2010; Pénicaud et al., 2013 inter alia). We report the first investigation of the task-negative network in Deaf signers and its functional connectivity-the temporal correlations among spatially remote neurophysiological events. We show that Deaf signers manifest increased functional connectivity between posterior cingulate/precuneus and left medial temporal gyrus (MTG), but also inferior parietal lobe and medial temporal gyrus in the right hemisphere- areas that have been found to show functional recruitment specifically during sign language processing. These findings suggest that the organization of the brain at the level of inter-network connectivity is likely affected by experience with processing visual language, although sensory deprivation could be another source of the difference. We hypothesize that connectivity alterations in the task negative network reflect predictive/automatized processing of the visual signal.

  15. Functional connectivity in task-negative network of the Deaf: effects of sign language experience

    Directory of Open Access Journals (Sweden)

    Evie Malaia

    2014-06-01

    Full Text Available Prior studies investigating cortical processing in Deaf signers suggest that life-long experience with sign language and/or auditory deprivation may alter the brain’s anatomical structure and the function of brain regions typically recruited for auditory processing (Emmorey et al., 2010; Pénicaud et al., 2013 inter alia. We report the first investigation of the task-negative network in Deaf signers and its functional connectivity—the temporal correlations among spatially remote neurophysiological events. We show that Deaf signers manifest increased functional connectivity between posterior cingulate/precuneus and left medial temporal gyrus (MTG, but also inferior parietal lobe and medial temporal gyrus in the right hemisphere- areas that have been found to show functional recruitment specifically during sign language processing. These findings suggest that the organization of the brain at the level of inter-network connectivity is likely affected by experience with processing visual language, although sensory deprivation could be another source of the difference. We hypothesize that connectivity alterations in the task negative network reflect predictive/automatized processing of the visual signal.

  16. Ultra-Weak Fiber Bragg Grating Sensing Network Coated with Sensitive Material for Multi-Parameter Measurements

    Directory of Open Access Journals (Sweden)

    Wei Bai

    2017-06-01

    Full Text Available A multi-parameter measurement system based on ultra-weak fiber Bragg grating (UFBG array with sensitive material was proposed and experimentally demonstrated. The UFBG array interrogation principle is time division multiplex technology with two semiconductor optical amplifiers as timing units. Experimental results showed that the performance of the proposed UFBG system is almost equal to that of traditional FBG, while the UFBG array system has obvious superiority with potential multiplexing ability for multi-point and multi-parameter measurement. The system experimented on a 144 UFBG array with the reflectivity of UFBG ~0.04% for the four target parameters: hydrogen, humidity, temperature and salinity. Moreover, a uniform solution was customized to divide the cross-sensitivity between temperature and other target parameters. It is expected that this scheme will be capable of handling thousands of multi-parameter sensors in a single fiber.

  17. The networked reception of transmedial universes: An experience-centered approach

    Directory of Open Access Journals (Sweden)

    Susana Tosca

    2016-06-01

    Full Text Available Building upon ten years of empirical work, this paper reflects on how to study increasingly complex user engagement with transmedial worlds. We examine our own analytical evolution from an initial aesthetic orientation to our current effort to incorporate the user´s own perspective through qualitative and quantitative studies. We argue that mapping user experience requires a sophisticated and holistic analytical approach - particularly, due to the popularity of social media platforms. We conclude the article by developing the concept of "networked reception" to characterize new kinds of transmedial world experience afforded by social media, which allow users to distribute and communicate not only the content of media texts but also their own experience and reception of transmedial world “texts”.

  18. Multistatic Wireless Fidelity Network Based Radar – Results of the Chrcynno Experiment

    Directory of Open Access Journals (Sweden)

    S. Rzewuski

    2014-04-01

    Full Text Available This paper presents the theory and experimental result of passive radar using WIFI transmitters as illuminators of opportunity. As a result of experiments conducted on 17th August 2013 at airfield Chrcynno a Cessna C208 airplane was detected and tracked using multistatic passive radar system based on low power signal from WIFI network nodes, which were acting as non cooperative illuminators of opportunity. In the experiment 3 wireless access points were communicating with each other and illuminating the radar scene (airfield. The direct reference and reflected (surveillance signals have been acquired and processed using specially developed algorithm presented in the paper. After signal processing using Passive Coherent Location methods target has been detected. This paper describes in details the algorithms and the results of the experiment for the multistatic passive radar based on the WIFI signal.

  19. Preliminary - discrete fracture network modelling of tracer migration experiments at the SCV site

    Energy Technology Data Exchange (ETDEWEB)

    Dershowitz, W.S.; Wallmann, P.; Geier, J.E.; Lee, G. [Golder Associates Inc., Redmond, WA (United States)

    1991-09-01

    This report describes a numerical modelling study of solute transport within the Site Characterization and Validation (SCV) block at the Stripa site. The study was carried out with the FracMan/MAFIC package, utilizing statistics from stages 3 and 4 of the Stripa phase 3 Site Characterization and Validation project. Simulations were carried out to calibrate fracture solute transport properties against observations in the first stage of saline injection radar experiments. These results were then used to predict the performance of planned tracer experiments, using both particle tracking network solute transport, and pathways analysis approaches. Simulations were also carried out to predict results of the second stage of saline injection radar experiments. (au) (34 refs.).

  20. Cost-Sensitive Radial Basis Function Neural Network Classifier for Software Defect Prediction

    Directory of Open Access Journals (Sweden)

    P. Kumudha

    2016-01-01

    Full Text Available Effective prediction of software modules, those that are prone to defects, will enable software developers to achieve efficient allocation of resources and to concentrate on quality assurance activities. The process of software development life cycle basically includes design, analysis, implementation, testing, and release phases. Generally, software testing is a critical task in the software development process wherein it is to save time and budget by detecting defects at the earliest and deliver a product without defects to the customers. This testing phase should be carefully operated in an effective manner to release a defect-free (bug-free software product to the customers. In order to improve the software testing process, fault prediction methods identify the software parts that are more noted to be defect-prone. This paper proposes a prediction approach based on conventional radial basis function neural network (RBFNN and the novel adaptive dimensional biogeography based optimization (ADBBO model. The developed ADBBO based RBFNN model is tested with five publicly available datasets from the NASA data program repository. The computed results prove the effectiveness of the proposed ADBBO-RBFNN classifier approach with respect to the considered metrics in comparison with that of the early predictors available in the literature for the same datasets.

  1. Highly sensitive gas-phase explosive detection by luminescent microporous polymer networks.

    Science.gov (United States)

    Räupke, André; Palma-Cando, Alex; Shkura, Eugen; Teckhausen, Peter; Polywka, Andreas; Görrn, Patrick; Scherf, Ullrich; Riedl, Thomas

    2016-07-04

    We propose microporous networks (MPNs) of a light emitting spiro-carbazole based polymer (PSpCz) as luminescent sensor for nitro-aromatic compounds. The MPNs used in this study can be easily synthesized on arbitrarily sized/shaped substrates by simple and low-cost electrochemical deposition. The resulting MPN afford an extremely high specific surface area of 1300 m(2)/g, more than three orders of magnitude higher than that of the thin films of the respective monomer. We demonstrate, that the luminescence of PSpCz is selectively quenched by nitro-aromatic analytes, e.g. nitrobenzene, 2,4-DNT and TNT. In striking contrast to a control sample based on non-porous spiro-carbazole, which does not show any luminescence quenching upon exposure to TNT at levels of 3 ppm and below, the microporous PSpCz shows a clearly detectable response even at TNT concentrations as low as 5 ppb, clearly demonstrating the advantage of microporous films as luminescent sensors for traces of explosive analytes. This level states the vapor pressure of TNT at room temperature.

  2. Cost-Sensitive Radial Basis Function Neural Network Classifier for Software Defect Prediction.

    Science.gov (United States)

    Kumudha, P; Venkatesan, R

    Effective prediction of software modules, those that are prone to defects, will enable software developers to achieve efficient allocation of resources and to concentrate on quality assurance activities. The process of software development life cycle basically includes design, analysis, implementation, testing, and release phases. Generally, software testing is a critical task in the software development process wherein it is to save time and budget by detecting defects at the earliest and deliver a product without defects to the customers. This testing phase should be carefully operated in an effective manner to release a defect-free (bug-free) software product to the customers. In order to improve the software testing process, fault prediction methods identify the software parts that are more noted to be defect-prone. This paper proposes a prediction approach based on conventional radial basis function neural network (RBFNN) and the novel adaptive dimensional biogeography based optimization (ADBBO) model. The developed ADBBO based RBFNN model is tested with five publicly available datasets from the NASA data program repository. The computed results prove the effectiveness of the proposed ADBBO-RBFNN classifier approach with respect to the considered metrics in comparison with that of the early predictors available in the literature for the same datasets.

  3. Status Report on Scoping Reactor Physics and Sensitivity/Uncertainty Analysis of LR-0 Reactor Molten Salt Experiments

    Energy Technology Data Exchange (ETDEWEB)

    Brown, Nicholas R. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). Reactor and Nuclear Systems Division; Mueller, Donald E. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). Reactor and Nuclear Systems Division; Patton, Bruce W. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). Reactor and Nuclear Systems Division; Powers, Jeffrey J. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). Reactor and Nuclear Systems Division

    2016-08-31

    Experiments are being planned at Research Centre Rež (RC Rež) to use the FLiBe (2 7LiF-BeF2) salt from the Molten Salt Reactor Experiment (MSRE) to perform reactor physics measurements in the LR-0 low power nuclear reactor. These experiments are intended to inform on neutron spectral effects and nuclear data uncertainties for advanced reactor systems utilizing FLiBe salt in a thermal neutron energy spectrum. Oak Ridge National Laboratory (ORNL) is performing sensitivity/uncertainty (S/U) analysis of these planned experiments as part of the ongoing collaboration between the United States and the Czech Republic on civilian nuclear energy research and development. The objective of these analyses is to produce the sensitivity of neutron multiplication to cross section data on an energy-dependent basis for specific nuclides. This report provides a status update on the S/U analyses of critical experiments at the LR-0 Reactor relevant to fluoride salt-cooled high temperature reactor (FHR) and liquid-fueled molten salt reactor (MSR) concepts. The S/U analyses will be used to inform design of FLiBe-based experiments using the salt from MSRE.

  4. New SCALE Sensitivity/Uncertainty Capabilities Applied to Bias Estimation and to Design of MIRTE Reference Experiments

    Energy Technology Data Exchange (ETDEWEB)

    Rearden, Bradley T [ORNL; Duhamel, Isabelle [Institut de Radioprotection et de Surete Nucleaire; Letang, Eric [Institut de Radioprotection et de Surete Nucleaire

    2009-01-01

    New TSUNAMI tools of SCALE 6, TSURFER and TSAR, are demonstrated to examine the bias effects of small-worth test materials, relative to reference experiments. TSURFER is a data adjustment bias and bias uncertainty assessment tool, and TSAR computes the sensitivity of the change in reactivity between two systems to the cross-section data common to their calculation. With TSURFER, it is possible to examine biases and bias uncertainties in fine detail. For replacement experiments, the application of TSAR to TSUNAMI-3D sensitivity data for pairs of experiments allows the isolation of sources of bias that could otherwise be obscured by materials with more worth in an individual experiment. The application of TSUNAMI techniques in the design of nine reference experiments for the MIRTE program will allow application of these advanced techniques to data acquired in the experimental series. The validation of all materials in a complex criticality safety application likely requires consolidating information from many different critical experiments. For certain materials, such as structural materials or fission products, only a limited number of critical experiments are available, and the fuel and moderator compositions of the experiments may differ significantly from those of the application. In these cases, it is desirable to extract the computational bias of a specific material from an integral keff measurement and use that information to quantify the bias due to the use of the same material in the application system. Traditional parametric and nonparametric methods are likely to prove poorly suited for such a consolidation of specific data components from a diverse set of experiments. An alternative choice for consolidating specific data from numerous sources is a data adjustment tool, like the ORNL tool TSURFER (Tool for Sensitivity/Uncertainty analysis of Response Functionals using Experimental Results) from SCALE 6.1 However, even with TSURFER, it may be difficult to

  5. Climate-signal changes in a temperature-sensitive dendroclimatic network: the influence of site aspect

    Science.gov (United States)

    Leonelli, Giovanni; Pelfini, Manuela; Battipaglia, Giovanna; Cherubini, Paolo

    2010-05-01

    especially for S- and W-facing site chronologies). On the other hand, trees from N-facing sites showed an increasing sensitivity to July temperatures, especially since the period 1911-1970. Our results underline that some climatic factors related to slope aspect (e.g. temperature regime, snow-cover persistence or growing season length) play a key role in limiting P. cembra tree-ring growth at high altitudes, especially in N-facing sites. Moreover, it is evident at all sites that at high altitudes, low temperatures at the beginning of the growing season no longer limit growth as they did in earlier decades. Stronger changes are involving especially the S- and W-facing sites that in the past were more limited by June temperature, whereas trees on N-facing slopes are generally less adapted to warmer conditions at the beginning of the growing season (June) and therefore respond less to an increasing air temperature. We point out the importance of testing growth-climate relationships over time to detect possible trends in climate sensitivity. In fact, wide variation in climate sensitivity over time could lead to over- or underestimations of past temperatures. Moreover, our findings showed that site ecology can affect dendroclimatic reconstructions.

  6. Identification of Jets Containing b-Hadrons with Recurrent Neural Networks at the ATLAS Experiment

    CERN Multimedia

    CERN. Geneva

    2017-01-01

    A novel b-jet identification algorithm is constructed with a Recurrent Neural Network (RNN) at the ATLAS Experiment. This talk presents the expected performance of the RNN based b-tagging in simulated $t \\bar t$ events. The RNN based b-tagging processes properties of tracks associated to jets which are represented in sequences. In contrast to traditional impact-parameter-based b-tagging algorithms which assume the tracks of jets are independent from each other, RNN based b-tagging can exploit the spatial and kinematic correlations of tracks which are initiated from the same b-hadrons. The neural network nature of the tagging algorithm also allows the flexibility of extending input features to include more track properties than can be effectively used in traditional algorithms.

  7. Incorporating Collaborative, Interactive Experiences into a Technology-Facilitated Professional Learning Network for Pre-Service Science Teachers

    Science.gov (United States)

    Delaney, Seamus; Redman, Christine

    2014-01-01

    This paper describes the utilisation of a technology-facilitated professional learning network (PLN) for pre-service teachers, centred on chemical demonstrations. The network provided direct experiences designed to extend their pedagogical content knowledge on demonstrations in Chemistry teaching. It provided scaffolded opportunities to…

  8. Sensitivity of MENA Tropical Rainbelt to Dust Shortwave Absorption: A High Resolution AGCM Experiment

    KAUST Repository

    Bangalath, Hamza Kunhu

    2016-06-13

    Shortwave absorption is one of the most important, but the most uncertain, components of direct radiative effect by mineral dust. It has a broad range of estimates from different observational and modeling studies and there is no consensus on the strength of absorption. To elucidate the sensitivity of the Middle East and North Africa (MENA) tropical summer rainbelt to a plausible range of uncertainty in dust shortwave absorption, AMIP-style global high resolution (25 km) simulations are conducted with and without dust, using the High-Resolution Atmospheric Model (HiRAM). Simulations with dust comprise three different cases by assuming dust as a very efficient, standard and inefficient absorber. Inter-comparison of these simulations shows that the response of the MENA tropical rainbelt is extremely sensitive to the strength of shortwave absorption. Further analyses reveal that the sensitivity of the rainbelt stems from the sensitivity of the multi-scale circulations that define the rainbelt. The maximum response and sensitivity are predicted over the northern edge of the rainbelt, geographically over Sahel. The sensitivity of the responses over the Sahel, especially that of precipitation, is comparable to the mean state. Locally, the response in precipitation reaches up to 50% of the mean, while dust is assumed to be a very efficient absorber. Taking into account that Sahel has a very high climate variability and is extremely vulnerable to changes in precipitation, the present study suggests the importance of reducing uncertainty in dust shortwave absorption for a better simulation and interpretation of the Sahel climate.

  9. Depletion analysis and sensitivity study of PHENIX fuel-irradiation experiments

    Energy Technology Data Exchange (ETDEWEB)

    Biswas, D.; Kallfelz, J.M.; White, J.R.

    1981-01-01

    The experimental results are in the form of various U and Pu atom density ratios (R/sub E/) and burnup (BU) values. The results were for samples irradiated during the first three cycles in the central zone of PHENIX. The time-dependent sensitivity study was performed with the depletion generalized perturbation code DEPTH-CHARGE, to investigate the sensitivity of R/sub E/ to cross sections and to absolute flux level changes. The depletion analysis was performed using ENDS/B-IV data, an (R-Z) model, and the VENTURE Code system. 2 tables.

  10. The Brain on Art: Intense Aesthetic Experience Activates the Default Mode Network

    Directory of Open Access Journals (Sweden)

    Edward A Vessel

    2012-04-01

    Full Text Available Aesthetic responses to visual art comprise multiple types of experiences, from sensation and perception to emotion and self-reflection. Moreover, aesthetic experience is highly individual, with observers varying significantly in their responses to the same artwork. Combining fMRI and behavioral analysis of individual differences in aesthetic response, we identify two distinct patterns of neural activity exhibited by different subnetworks. Activity increased linearly with observers’ ratings (4-level scale in sensory (occipito-temporal regions. Activity in the striatum also varied linearly with ratings, with below-baseline activations for low-rated artworks. In contrast, a network of frontal regions showed a step-like increase only for the most moving artworks (4 ratings and non-differential activity for all others. This included several regions belonging to the default mode network previously associated with self-referential mentation. Our results suggest that aesthetic experience involves the integration of sensory and emotional reactions in a manner linked with their personal relevance.

  11. The DISC (Diabetes in Social Context Study-evaluation of a culturally sensitive social network intervention for diabetic patients in lower socioeconomic groups: a study protocol

    Directory of Open Access Journals (Sweden)

    Vissenberg Charlotte

    2012-03-01

    Full Text Available Abstract Background Compared to those in higher socioeconomic groups, diabetic patients in lower socioeconomic groups have less favourable metabolic control and experience more diabetes-related complications. They encounter specific barriers that hinder optimal diabetes self-management, including a lack of social support and other psychosocial mechanisms in their immediate social environments. Powerful Together with Diabetes is a culturally sensitive social network intervention specifically targeted to ethnic Dutch, Moroccan, Turkish, and Surinamese diabetic patients in lower socioeconomic groups. For ten months, patients will participate in peer support groups in which they will share experiences, support each other in maintaining healthy lifestyles, and learn skills to resist social pressure. At the same time, their significant others will also receive an intervention, aimed at maximizing support for and minimizing the negative social influences on diabetes self-management. This study aims to test the effectiveness of Powerful Together with Diabetes. Methods/Design We will use a quasi-experimental design with an intervention group (Group 1 and two comparison groups (Groups 2 and 3, N = 128 in each group. Group 1 will receive Powerful Together with Diabetes. Group 2 will receive Know your Sugar, a six-week group intervention that does not focus on the participants' social environments. Group 3 receives standard care only. Participants in Groups 1 and 2 will be interviewed and physically examined at baseline, 3, 10, and 16 months. We will compare their haemoglobin A1C levels with the haemoglobin A1C levels of Group 3. Main outcome measures are haemoglobin A1C, diabetes-related quality of life, diabetes self-management, health-related, and intermediate outcome measures. We will conduct a process evaluation and a qualitative study to gain more insights into the intervention fidelity, feasibility, and changes in the psychosocial mechanism in the

  12. Balancing sensitivity and specificity: sixteen year's of experience from the mammography screening programme in Copenhagen, Denmark

    DEFF Research Database (Denmark)

    Utzon-Frank, Nicolai; Vejborg, Ilse; von Euler-Chelpin, My Catarina

    2011-01-01

    To report on sensitivity and specificity from 7 invitation rounds of the organised, population-based mammography screening programme started in Copenhagen, Denmark, in 1991, and offered biennially to women aged 50-69. Changes over time were related to organisation and technology....

  13. Decay Kinetics of UV-Sensitive Materials: An Introductory Chemistry Experiment

    Science.gov (United States)

    Via, Garrhett; Williams, Chelsey; Dudek, Raymond; Dudek, John

    2015-01-01

    First-order kinetic decay rates can be obtained by measuring the time-dependent reflection spectra of ultraviolet-sensitive objects as they returned from their excited, colored state back to the ground, colorless state. In this paper, a procedure is described which provides an innovative and unique twist on standard, undergraduate, kinetics…

  14. A Sensitive and Robust Enzyme Kinetic Experiment Using Microplates and Fluorogenic Ester Substrates

    Science.gov (United States)

    Johnson, R. Jeremy; Hoops, Geoffrey C.; Savas, Christopher J.; Kartje, Zachary; Lavis, Luke D.

    2015-01-01

    Enzyme kinetics measurements are a standard component of undergraduate biochemistry laboratories. The combination of serine hydrolases and fluorogenic enzyme substrates provides a rapid, sensitive, and general method for measuring enzyme kinetics in an undergraduate biochemistry laboratory. In this method, the kinetic activity of multiple protein…

  15. Integrating atomistic molecular dynamics simulations, experiments, and network analysis to study protein dynamics

    DEFF Research Database (Denmark)

    Papaleo, Elena

    2015-01-01

    that we observe and the functional properties of these important cellular machines. To make progresses in this direction, we need to improve the physical models used to describe proteins and solvent in molecular dynamics, as well as to strengthen the integration of experiments and simulations to overcome...... simulations with attention to the effects that can be propagated over long distances and are often associated to important biological functions. In this context, approaches inspired by network analysis can make an important contribution to the analysis of molecular dynamics simulations....

  16. Impact of the quenching of gA on the sensitivity of 0 ν β β experiments

    Science.gov (United States)

    Suhonen, Jouni

    2017-11-01

    Detection of the neutrinoless β β (0 ν β β ) decay is of high priority in the particle- and neutrino-physics communities. The detectability of this decay mode is strongly influenced by the value of the weak axial-vector coupling constant gA. The recent nuclear-model analyses of β and β β decays suggest that the value of gA could be dramatically quenched, reaching ratios of gAfree/gA≈4 , where gAfree=1.27 is the free, neutron-decay, value of gA. The effects of this quenching appear devastating for the sensitivity of the present and future 0 ν β β experiments since the fourth power of this ratio scales the 0 ν β β half-lives. This, in turn, could lead to some two orders of magnitude less sensitivity for the 0 ν β β experiments. In the present article it is shown that by using a consistent approach to both the two-neutrino β β and 0 ν β β decays by the proton-neutron quasiparticle random-phase approximation, the feared two-orders-of-magnitude reduction in the sensitivity of the 0 ν β β experiments actually shrinks to a reduction by factors in the range 2 -6 . This certainly has dramatic consequences for the potential to detect the 0 ν β β decay.

  17. A Progress Review on Soot Experiments and Modeling in the Engine Combustion Network (ECN)

    KAUST Repository

    Skeen, Scott A.

    2016-04-05

    The 4th Workshop of the Engine Combustion Network (ECN) was held September 5-6, 2015 in Kyoto, Japan. This manuscript presents a summary of the progress in experiments and modeling among ECN contributors leading to a better understanding of soot formation under the ECN “Spray A” configuration and some parametric variants. Relevant published and unpublished work from prior ECN workshops is reviewed. Experiments measuring soot particle size and morphology, soot volume fraction (fv), and transient soot mass have been conducted at various international institutions providing target data for improvements to computational models. Multiple modeling contributions using both the Reynolds Averaged Navier-Stokes (RANS) Equations approach and the Large-Eddy Simulation (LES) approach have been submitted. Among these, various chemical mechanisms, soot models, and turbulence-chemistry interaction (TCI) methodologies have been considered.

  18. Three-dimensional Dendritic Needle Network model with application to Al-Cu directional solidification experiments

    Science.gov (United States)

    Tourret, D.; Karma, A.; Clarke, A. J.; Gibbs, P. J.; Imhoff, S. D.

    2015-06-01

    We present a three-dimensional (3D) extension of a previously proposed multi-scale Dendritic Needle Network (DNN) approach for the growth of complex dendritic microstructures. Using a new formulation of the DNN dynamics equations for dendritic paraboloid-branches of a given thickness, one can directly extend the DNN approach to 3D modeling. We validate this new formulation against known scaling laws and analytical solutions that describe the early transient and steady-state growth regimes, respectively. Finally, we compare the predictions of the model to in situ X-ray imaging of Al-Cu alloy solidification experiments. The comparison shows a very good quantitative agreement between 3D simulations and thin sample experiments. It also highlights the importance of full 3D modeling to accurately predict the primary dendrite arm spacing that is significantly over-estimated by 2D simulations.

  19. Leuconostoc mesenteroides growth in food products: prediction and sensitivity analysis by adaptive-network-based fuzzy inference systems.

    Directory of Open Access Journals (Sweden)

    Hue-Yu Wang

    Full Text Available BACKGROUND: An adaptive-network-based fuzzy inference system (ANFIS was compared with an artificial neural network (ANN in terms of accuracy in predicting the combined effects of temperature (10.5 to 24.5°C, pH level (5.5 to 7.5, sodium chloride level (0.25% to 6.25% and sodium nitrite level (0 to 200 ppm on the growth rate of Leuconostoc mesenteroides under aerobic and anaerobic conditions. METHODS: THE ANFIS AND ANN MODELS WERE COMPARED IN TERMS OF SIX STATISTICAL INDICES CALCULATED BY COMPARING THEIR PREDICTION RESULTS WITH ACTUAL DATA: mean absolute percentage error (MAPE, root mean square error (RMSE, standard error of prediction percentage (SEP, bias factor (Bf, accuracy factor (Af, and absolute fraction of variance (R (2. Graphical plots were also used for model comparison. CONCLUSIONS: The learning-based systems obtained encouraging prediction results. Sensitivity analyses of the four environmental factors showed that temperature and, to a lesser extent, NaCl had the most influence on accuracy in predicting the growth rate of Leuconostoc mesenteroides under aerobic and anaerobic conditions. The observed effectiveness of ANFIS for modeling microbial kinetic parameters confirms its potential use as a supplemental tool in predictive mycology. Comparisons between growth rates predicted by ANFIS and actual experimental data also confirmed the high accuracy of the Gaussian membership function in ANFIS. Comparisons of the six statistical indices under both aerobic and anaerobic conditions also showed that the ANFIS model was better than all ANN models in predicting the four kinetic parameters. Therefore, the ANFIS model is a valuable tool for quickly predicting the growth rate of Leuconostoc mesenteroides under aerobic and anaerobic conditions.

  20. Leuconostoc mesenteroides growth in food products: prediction and sensitivity analysis by adaptive-network-based fuzzy inference systems.

    Science.gov (United States)

    Wang, Hue-Yu; Wen, Ching-Feng; Chiu, Yu-Hsien; Lee, I-Nong; Kao, Hao-Yun; Lee, I-Chen; Ho, Wen-Hsien

    2013-01-01

    An adaptive-network-based fuzzy inference system (ANFIS) was compared with an artificial neural network (ANN) in terms of accuracy in predicting the combined effects of temperature (10.5 to 24.5°C), pH level (5.5 to 7.5), sodium chloride level (0.25% to 6.25%) and sodium nitrite level (0 to 200 ppm) on the growth rate of Leuconostoc mesenteroides under aerobic and anaerobic conditions. THE ANFIS AND ANN MODELS WERE COMPARED IN TERMS OF SIX STATISTICAL INDICES CALCULATED BY COMPARING THEIR PREDICTION RESULTS WITH ACTUAL DATA: mean absolute percentage error (MAPE), root mean square error (RMSE), standard error of prediction percentage (SEP), bias factor (Bf), accuracy factor (Af), and absolute fraction of variance (R (2)). Graphical plots were also used for model comparison. The learning-based systems obtained encouraging prediction results. Sensitivity analyses of the four environmental factors showed that temperature and, to a lesser extent, NaCl had the most influence on accuracy in predicting the growth rate of Leuconostoc mesenteroides under aerobic and anaerobic conditions. The observed effectiveness of ANFIS for modeling microbial kinetic parameters confirms its potential use as a supplemental tool in predictive mycology. Comparisons between growth rates predicted by ANFIS and actual experimental data also confirmed the high accuracy of the Gaussian membership function in ANFIS. Comparisons of the six statistical indices under both aerobic and anaerobic conditions also showed that the ANFIS model was better than all ANN models in predicting the four kinetic parameters. Therefore, the ANFIS model is a valuable tool for quickly predicting the growth rate of Leuconostoc mesenteroides under aerobic and anaerobic conditions.

  1. [Capsule endoscopy in a supra-regional network corporation: experience in more than 1000 cases].

    Science.gov (United States)

    Farnbacher, M J; Hagel, A F; Keles, M; Meier, M; Schneider, T

    2014-09-01

    Capsule endoscopy (CE) is firmly established as a standard procedure in the diagnostic algorithm of mid gastrointestinal (GI) bleeding. Despite its excellent diagnostic yield, missing expertise, reading time and financial expenditure limit an area-wide availability. A multicentric cooperation might compensate these disadvantages. The CE device was bought by a centrally located hospital (CH). CE-equipment is transported to the network partner (NP) on request and the procedure performed at the spot. Video reading is exclusively done in the CH. Between January 2002 and July 2013, 1026 CE (548 m, 478f; 64 ± 16, 13 - 93 yrs.) were performed within the network. 744/1026 (73 %) CE were done at 17 NP, 282/1026 (27 %) in the CH. Between 2002 (n = 39) and 2012 (n = 136) the annual number of CE increased threefold. Leading indication for CE was suspected mid GI-bleeding (80 %). Mean latencies between requested date and actual examination were less than 24 h and 2 days between CE performance and report. 95 % of the capital investment in each cooperating hospital could be avoided by sharing one workstation within the network. The experience from more than 1000 CE show that long-term multicentric utilization of CE equipment is feasible. Such a network runs at stable procedural quality levels similar to an in-house supply, allows an economic as well as area-wide availability of CE and improves reading expertise by centralized video evaluation. © Georg Thieme Verlag KG Stuttgart · New York.

  2. Evolution of dilatant fracture networks in a normal fault — Evidence from 4D model experiments

    Science.gov (United States)

    Holland, Marc; van Gent, Heijn; Bazalgette, Loïc; Yassir, Najwa; Hoogerduijn Strating, Eilard H.; Urai, Janos L.

    2011-04-01

    Dilatant fractures in normal fault zones are widely recognized as major pathways of fluid flow in the upper crust where the ratio of rock strength and effective stress is suitable for their formation, but the structure of these fracture networks in 3D, their connectivity and their temporal evolution is poorly known. Here we build on 2D studies of scaled models of fracture networks in dilatant normal fault zones, using a series of X-ray computer tomographic scans of a physical model. We show how the dilatant fracture network evolves in 3D, as a complex self-organizing system with self-similar geometry. We processed the CT-scan data using a threshold filter to identify the open fracture volume, to allow visual and quantitative analysis of the evolving fracture system in 3D. Dilatant jogs initiated along the evolving fault plane coalesce into a self-similar percolating volume (Fd = 1.91). The fracture volume increases non-linearly with progressive displacement as the velocity of the fault blocks diverges from the master fault orientation and we infer that the normal stress on the fault decreases correspondingly. This process continues until the system triggers the formation of antithetic faults, with a corresponding increase in normal stress on the master fault and a decrease in the rate of fracture volume creation. We infer that although parameters like the width of the fractures are not scaled with the same ratio as length and stress, the processes and evolution of fracture geometries in our model are robust and apply to a wide range of normal fault zones in nature. Since our physical model does not involve chemical processes such as cementation or fault healing, the experiment suggests that fault systems can show a non-linear change of fracture network properties caused by a geometric evolution only.

  3. Impact of changing DOC concentrations on the potential distribution of acid sensitive biota in a boreal stream network

    Directory of Open Access Journals (Sweden)

    H. Laudon

    2008-03-01

    Full Text Available DOC concentrations have increased in many surface waters in Europe and North America over the past few decades. As DOC exudes a strong influence on pH this DOC increase could have detrimental effects on acid sensitive biota in many streams and lakes. To investigate the potential implications of changes in the DOC concentration on stream water biota, we have used a mesoscale boreal stream network in northern Sweden as a case study. The network was sampled for stream water chemistry at 60 locations during both winter base flow and spring flood periods, representing the extremes experienced annually in these streams both in terms of discharge and acidity. The effect of changing DOC on pH was modeled for all sampling locations using an organic acid model, with input DOC concentrations for different scenarios adjusted by between −30% and +50% from measured present concentrations. The resulting effect on pH was then used to quantify the proportion of stream length in the catchment with pH below the acid thresholds of pH 5.5 and pH 5.0. The results suggest that a change in stream water DOC during base flow would have only a limited effect on pH and hence on the stream length with pH below the acid thresholds. During the spring flood on the other hand a change in DOC would strongly influence pH and the stream length with pH below the acid thresholds. For example an increase in DOC concentration of 30% at all sites would increase the proportion of stream length with pH below 5.5 from 37% to 65%, and the proportion of stream length with pH below 5.0 would increase from 18% to 27%. The results suggest that in high DOC waters, even a marginal change in the DOC concentration could impact acid sensitive biota in a large portion of the aquatic landscape.

  4. Sensitivity to cocaine in adult mice is due to interplay between genetic makeup, early environment and later experience.

    Science.gov (United States)

    Di Segni, Matteo; Andolina, Diego; Coassin, Alessandra; Accoto, Alessandra; Luchetti, Alessandra; Pascucci, Tiziana; Luzi, Carla; Lizzi, Anna Rita; D'Amato, Francesca R; Ventura, Rossella

    2017-10-01

    Although early aversive postnatal events are known to increase the risk to develop psychiatric disorders later in life, rarely they determine alone the nature and outcome of the psychopathology, indicating that interaction with genetic factors is crucial for expression of psychopathologies in adulthood. Moreover, it has been suggested that early life experiences could have negative consequences or confer adaptive value in different individuals. Here we suggest that resilience or vulnerability to adult cocaine sensitivity depends on a "triple interaction" between genetic makeup x early environment x later experience. We have recently showed that Repeated Cross Fostering (RCF; RCF pups were fostered by four adoptive mothers from postnatal day 1 to postnatal day 4. Pups were left with the last adoptive mother until weaning) experienced by pups affected the response to a negative experience in adulthood in opposite direction in two genotypes leading DBA2/J, but not C57BL/6J mice, toward an "anhedonia-like" phenotype. Here we investigate whether exposure to a rewarding stimulus, instead of a negative one, in adulthood induces an opposite behavioral outcome. To test this hypothesis, we investigated the long-lasting effects of RCF on cocaine sensitivity in C57 and DBA female mice by evaluating conditioned place preference induced by different cocaine doses and catecholamine prefrontal-accumbal response to cocaine using a "dual probe" in vivo microdialysis procedure. Moreover, cocaine-induced c-Fos activity was assessed in different brain regions involved in processing of rewarding stimuli. Finally, cocaine-induced spine changes were evaluated in the prefrontal-accumbal system. RCF experience strongly affected the behavioral, neurochemical and morphological responses to cocaine in adulthood in opposite direction in the two genotypes increasing and reducing, respectively, the sensitivity to cocaine in C57 and DBA mice. Copyright © 2017 Elsevier Ltd. All rights reserved.

  5. Teaching examples for the design of experiments: geographical sensitivity and the self-fulfilling prophecy.

    Science.gov (United States)

    Lendrem, Dennis W; Lendrem, B Clare; Rowland-Jones, Ruth; D'Agostino, Fabio; Linsley, Matt; Owen, Martin R; Isaacs, John D

    2016-01-01

    Many scientists believe that small experiments, guided by scientific intuition, are simpler and more efficient than design of experiments. This belief is strong and persists even in the face of data demonstrating that it is clearly wrong. In this paper, we present two powerful teaching examples illustrating the dangers of small experiments guided by scientific intuition. We describe two, simple, two-dimensional spaces. These two spaces give rise to, and at the same time appear to generate supporting data for, scientific intuitions that are deeply flawed or wholly incorrect. We find these spaces useful in unfreezing scientific thinking and challenging the misplaced confidence in scientific intuition. Copyright © 2015 John Wiley & Sons, Ltd.

  6. General practitioners' experiences with provision of healthcare to patients with self-reported multiple chemical sensitivity

    DEFF Research Database (Denmark)

    Skovbjerg, Sine; Johansen, Jeanne Duus; Rasmussen, Alice

    2009-01-01

    OBJECTIVE: To describe general practitioners' (GPs') evaluation of and management strategies in relation to patients who seek medical advice because of multiple chemical sensitivity (MCS). DESIGN: A nationwide cross-sectional postal questionnaire survey. The survey included a sample of 1000 Danish....../biologic by 27.6%, and as psychological by 7.2%. Partial or complete avoidance of chemical exposures was recommended by 86.3%. Clinical guidelines, diagnostic tools, or more insight in the pathophysiology were requested by 84.5% of the GPs. CONCLUSION: Despite the lack of formal diagnostic labelling the patient...

  7. The Importance of Networking in the Academic and Professional Experiences of Racial Minority Students in the USA

    Science.gov (United States)

    Davis, Dannielle Joy; Warfield, Markeba

    2011-01-01

    Through examination of the experiences of minority undergraduate doctoral aspirants in the United States, this study points to the importance of academic and professional influences of networking, as well as its role in the academic attainment and professional experiences of underrepresented groups in academe. The findings suggest that networking…

  8. CAN LACK OF EXPERIENCE DELAY THE END OF THE SENSITIVE PHASE FOR SONG LEARNING

    NARCIS (Netherlands)

    SLATER, PJB; JONES, A; TENCATE, C

    1993-01-01

    Some bird species will modify their songs in adulthood, whereas in others, once developed, song appears relatively fixed. However, even in some of the latter, social experience may lead birds to learn songs later than was previously thought possible. Do age-limited learners really exist or is

  9. Bandpass characteristics of high-frequency sensitivity and visual experience in blindsight

    NARCIS (Netherlands)

    Seifert, Doerthe; Falter, Christine; Strasburger, Hans; Elliott, Mark A.

    Patient RP suffers a unilateral right homonymous quadrant anopia but demonstrates better than chance discrimination for Stimuli presented in the blind field at temporal frequencies between 33 and 47 Hz (all significant at p <05, binomial) Examination of her reports of visual experience during

  10. Sensitivity analysis and optimization of system dynamics models : Regression analysis and statistical design of experiments

    NARCIS (Netherlands)

    Kleijnen, J.P.C.

    1995-01-01

    This tutorial discusses what-if analysis and optimization of System Dynamics models. These problems are solved, using the statistical techniques of regression analysis and design of experiments (DOE). These issues are illustrated by applying the statistical techniques to a System Dynamics model for

  11. Undergraduates' Experience of Preparedness for Engaging with Sensitive Research Topics Using Qualitative Research

    Science.gov (United States)

    Simpson, Kerri L.; Wilson-Smith, Kevin

    2017-01-01

    This research explored the experience of five undergraduates who engaged with qualitative research as part of their final dissertation project. There have been concerns raised over the emotional safety of researchers carrying out qualitative research, which increases when researchers are inexperienced making this a poignant issues for lectures…

  12. Sensitivity Analysis of the Artificial Neural Network Outputs in Friction Stir Lap Joining of Aluminum to Brass

    Directory of Open Access Journals (Sweden)

    Mohammad Hasan Shojaeefard

    2013-01-01

    Full Text Available Al-Mg and CuZn34 alloys were lap joined using friction stir welding while the aluminum alloy sheet was placed on the CuZn34. In addition, the mechanical properties of each sample were characterized using shear tests. Scanning electron microscopy (SEM and X-ray diffraction analysis were used to probe chemical compositions. An artificial neural network model was developed to simulate the correlation between the Friction Stir Lap Welding (FSLW parameters and mechanical properties. Subsequently, a sensitivity analysis was performed to investigate the effect of each input parameter on the output in terms of magnitude and direction. Four methods, namely, the “PaD” method, the “Weights” method, the “Profile” method, and the “backward stepwise” method, which can give the relative contribution and/or the contribution profile of the input factors, were compared. The PaD method, giving the most complete results, was found to be the most useful, followed by the Profile method that gave the contribution profile of the input variables.

  13. Robust On-Demand Multipath Routing with Dynamic Path Upgrade for Delay-Sensitive Data over Ad Hoc Networks

    Directory of Open Access Journals (Sweden)

    Sunil Kumar

    2013-01-01

    Full Text Available Node mobility in mobile ad hoc networks (MANETs causes frequent route breakages and intermittent link stability. In this paper, we introduce a robust routing scheme, known as ad hoc on-demand multipath distance vector with dynamic path update (AOMDV-DPU, for delay-sensitive data transmission over MANET. The proposed scheme improves the AOMDV scheme by incorporating the following features: (i a routing metric based on the combination of minimum hops and received signal strength indicator (RSSI for discovery of reliable routes; (ii a local path update mechanism which strengthens the route, reduces the route breakage frequency, and increases the route longevity; (iii a keep alive mechanism for secondary route maintenance which enables smooth switching between routes and reduces the route discovery frequency; (iv a packet salvaging scheme to improve packet delivery in the event of a route breakage; and (v low HELLO packet overhead. The simulations are carried out in ns-2 for varying node speeds, number of sources, and traffic load conditions. Our AOMDV-DPU scheme achieves significantly higher throughput, lower delay, routing overhead, and route discovery frequency and latency compared to AOMDV. For H.264 compressed video traffic, AOMDV-DPU scheme achieves 3 dB or higher PSNR gain over AOMDV at both low and high node speeds.

  14. Heating-Rate-Triggered Carbon-Nanotube-based 3-Dimensional Conducting Networks for a Highly Sensitive Noncontact Sensing Device

    KAUST Repository

    Tai, Yanlong

    2016-01-28

    Recently, flexible and transparent conductive films (TCFs) are drawing more attention for their central role in future applications of flexible electronics. Here, we report the controllable fabrication of TCFs for moisture-sensing applications based on heating-rate-triggered, 3-dimensional porous conducting networks through drop casting lithography of single-walled carbon nanotube (SWCNT)/poly(3,4-ethylenedioxythiophene)-polystyrene sulfonate (PEDOT:PSS) ink. How ink formula and baking conditions influence the self-assembled microstructure of the TCFs is discussed. The sensor presents high-performance properties, including a reasonable sheet resistance (2.1 kohm/sq), a high visible-range transmittance (>69%, PET = 90%), and good stability when subjected to cyclic loading (>1000 cycles, better than indium tin oxide film) during processing, when formulation parameters are well optimized (weight ratio of SWCNT to PEDOT:PSS: 1:0.5, SWCNT concentration: 0.3 mg/ml, and heating rate: 36 °C/minute). Moreover, the benefits of these kinds of TCFs were verified through a fully transparent, highly sensitive, rapid response, noncontact moisture-sensing device (5 × 5 sensing pixels).

  15. Emission Control in River Network System of the Taihu Basin for Water Quality Assurance of Water Environmentally Sensitive Areas

    Directory of Open Access Journals (Sweden)

    Xiao Wang

    2017-02-01

    Full Text Available As pollution incidents frequently occurred in the functional water areas of the Taihu Basin, Yangtze Delta, effective emission control to guarantee water quality in the Taihu Basin became the priority for environmental management. In this study, a new total emission control (TEC method was proposed with an emphasis on the concept of water environmentally sensitive areas (WESAs. This method was verified in Wujiang District and the techniques can be concluded in three steps: (1 a 1-D mathematical model for the study area was established and the model was calibrated using field measurement data; (2 based on an analysis of administrative planning and regulations, WESAs were identified as the main controlling objectives for emission control calculations. The weighting coefficient of local pollution sources was investigated to discuss the effectiveness of TEC on water quality improvement at WESAs; and (3 applying the river network mathematical model, water quality along the river segments was simulated under different pollution control plans. The results proved the effectiveness of TEC in the study area and indicated that a 14.6% reduction in the total amount of ammonia-nitrogen (NH3-N, as well as a 31.1% reduction in the total amount of chemical oxygen demand (CODcr, was essential in order to meet the water quality standard in the WESAs.

  16. Public participation in the implementation of the Natura 2000 network in Italy: the stakeholders’ experiences

    Directory of Open Access Journals (Sweden)

    Paletto A

    2017-02-01

    Full Text Available Public participation in the implementation of the Natura 2000 network in Italy: the stakeholders’ experiences. Natura 2000 is an ecological network of protected areas identified by the Habitats Directive (92/43/EEC and the Birds Directive (79/409/EC - recently replaced by the Directive 2009/147/EC - in order to ensure the long-term protection of endangered species in their natural habitats in European Union (EU territory. EU Member States are responsible for developing and implementing the procedures defined by Habitats Directive, but there are no specific recommendations about participation of stakeholders and local community in the decision-making process. Consequently, each country has adopted a different participatory strategy taking into account the principles of integration approach. The integration approach is based on combining human activities and nature conservation purposes in the same area or, at least, in areas in close proximity. In Italy, the implementation of Natura 2000 network was developed at local level (Regions and Autonomous Provinces using different approaches and procedures. Starting from these considerations, the aim of the study was to analyse the stakeholders’ involvement process during the implementation of Habitats Directive in Italy and the management of Natura 2000 sites. This study was realized using three main criteria with the respective indicators: (1 inclusiveness of participatory process; (2 democracy of participatory process; (3 cooperation and conflicts during the implementation process of Natura 2000 network. The data were collected through the administration by email of a semi-structured questionnaire to 56 stakeholders divided in four main groups of interest (public administrations, universities and research centres, environmental associations, private organizations. The results of the survey show that the participatory process was characterized by a low level of inclusiveness despite the existence

  17. Graph kernels, hierarchical clustering, and network community structure: experiments and comparative analysis

    Science.gov (United States)

    Zhang, S.; Ning, X.-M.; Zhang, X.-S.

    2007-05-01

    There has been a quickly growing interest in properties of complex networks, such as the small world property, power-law degree distribution, network transitivity, and community structure, which seem to be common to many real world networks. In this study, we consider the community property which is also found in many real networks. Based on the diffusion kernels of networks, a hierarchical clustering approach is proposed to uncover the community structure of different extent of complex networks. We test the method on some networks with known community structures and find that it can detect significant community structure in these networks. Comparison with related methods shows the effectiveness of the method.

  18. Desensitization protocol for highly sensitized renal transplant patients: A single-center experience

    Directory of Open Access Journals (Sweden)

    Vivek B Kute

    2011-01-01

    Full Text Available Highly sensitized patients are destined to remain untransplanted for long. Early transplantation results in cost-saving, reduced morbidity/mortality and improved quality of life. We carried out a prospective study to evaluate the efficacy and safety of desensitization protocol vis-à-vis patient/graft survival in living donor renal transplantation in highly sensitized patients. Between December 2008 and April 2010, 34 renal transplant (RTx patients underwent desensitization protocol. An anti-human globulin-enhanced lymphocytotoxicity crossmatch assay (AHG-CDC ≥25% and T-cell median channel shift (MCS >50, B-cell MCS >100 [flow crossmatch (FXM] were considered crossmatch (XM positive. All patients were administered bortezomib (1.3 mg/m 2 , days 1, 4, 8, 11, plasmapheresis, rabbit-anti-thymocyte globulin (r-ATG, mycophenolate mofetil (MMF and intravenous immunoglobulins (IVIg. LCXM and FXM were repeated post-protocol. In the event of persistent sensitization, additional bortezomib cycle was repeated along with plasmapheresis, IVIg, calcineurin inhibitors (CNI and rituximab. If the cross match (CMX was negative or acceptable, patients underwent RTx. Post-transplant immunosuppression consisted of prednisone, CNI and MMF. Biopsy was performed in the event of graft dysfunction and treated accordingly. There were 18 males and 16 females, with a mean age of 37.4 years. Mean dialysis duration was 14.9 ± 17.6 months. Average third party transfusions were 6.2 ± 4.5, 17.6% had autoimmune diseases, 20.6% were multi-para. Pre-protocol AHGXM was 55.3 ± 24.5%, T-cell crossmatch (TCXM was 122.4 ± 91.4 MCS and B-cell crossmatch (BCXM was 279 ± 142.9 MCS. Totally, 85.3% responded within 1 month with reduction in AHG-CDC to 19.9 ± 5.2%, TCXM to 24.7 ± 19.4 MCS and BCXM to 74.7 ± 34.8 MCS. Side effects noted in 38.2% were manageable. Over follow-up of 0.92 ± 0.8 years, patient/graft survival was 100%/88.2% and mean serum creatinine was 1.27 ± 0.32 mg

  19. Using the OASES-A to illustrate how network analysis can be applied to understand the experience of stuttering.

    Science.gov (United States)

    Siew, Cynthia S Q; Pelczarski, Kristin M; Yaruss, J Scott; Vitevitch, Michael S

    Network science uses mathematical and computational techniques to examine how individual entities in a system, represented by nodes, interact, as represented by connections between nodes. This approach has been used by Cramer et al. (2010) to make "symptom networks" to examine various psychological disorders. In the present analysis we examined a network created from the items in the Overall Assessment of the Speaker's Experience of Stuttering-Adult (OASES-A), a commonly used measure for evaluating adverse impact in the lives of people who stutter. The items of the OASES-A were represented as nodes in the network. Connections between nodes were placed if responses to those two items in the OASES-A had a correlation coefficient greater than ±0.5. Several network analyses revealed which nodes were "important" in the network. Several centrally located nodes and "key players" in the network were identified. A community detection analysis found groupings of nodes that differed slightly from the subheadings of the OASES-A. Centrally located nodes and "key players" in the network may help clinicians prioritize treatment. The different community structure found for people who stutter suggests that the way people who stutter view stuttering may differ from the way that scientists and clinicians view stuttering. Finally, the present analyses illustrate how the network approach might be applied to other speech, language, and hearing disorders to better understand how those disorders are experienced and to provide insights for their treatment. Copyright © 2016 Elsevier Inc. All rights reserved.

  20. Validation of OMI NO2 Data to Enhance EPA Ground Network Data: An RPC Experiment

    Science.gov (United States)

    Kleb, M. M.; Pippin, M. R.; Parker, P. A.; Rhew, R. D.; Szykman, J. J.; Neil, D. O.

    2007-12-01

    We present an RPC validation study to determine the potential use of OMI tropospheric NO2 column data to enhance spatial surface predictions of NO2 as an augmentation to the continuous NO2 ground network data collected by the State and Local Air Monitoring Stations (SLAMS) and National Air Monitoring Stations (NAMS) for the continental United States. Using one year of OMI and SLAMS/NAMS ground based data from the EPA's Air Quality System (AQS), NO2 values are compared using a variety of statistical techniques including a time series analysis at each EPA ground station in the continental United States, a site-by- site correlation analysis, site-by-site comparison of mean and standard deviation values, and regional (defined by the ten EPA regions) spatial statistics. In addition, a multivariate statistical prediction model with significance testing is developed to determine within a 95% confidence level the impact of concentration, latitude, region, season, environment (urban vs. rural), and pixel size on the correlation of OMI to EPA NO2 data. The robustness of the statistical model is evaluated using statistical methods. Results of this experiment quantify the ability to use OMI-derived NO2 observations to provide predicted surface concentrations to augment the coverage of the existing NO2 ground networks in regions of sparse or non-existent ground monitors. This predictive capability could facilitate a more capable and integrated observing network for NO2 and lead to more informed air quality management decisions at the local, state, and national level.

  1. Link-Layer and Network-Layer Performance of an Undersea Acoustic Network at Fleet Battle Experiment-India

    National Research Council Canada - National Science Library

    Hartfield, Grant

    2003-01-01

    .... Many factors constrain or impair undersea acoustic communications. Analysis of a sample portion of the data reveals insights about the overall throughput, latency, and reliability of the Seaweb network...

  2. Experiences with a Decade of Wireless Sensor Networks in Mountain Cryosphere Research

    Science.gov (United States)

    Beutel, Jan

    2017-04-01

    Research in geoscience depends on high-quality measurements over long periods of time in order to understand processes and to create and validate models. The promise of wireless sensor networks to monitor autonomously at unprecedented spatial and temporal scale motivated the use of this novel technology for studying mountain permafrost in the mid 2000s. Starting from a first experimental deployment to investigate the thermal properties of steep bedrock permafrost in 2006 on the Jungfraujoch, Switzerland at 3500 m asl using prototype wireless sensors the PermaSense project has evolved into a multi-site and multi-discipline initiative. We develop, deploy and operate wireless sensing systems customized for long-term autonomous operation in high-mountain environments. Around this central element, we develop concepts, methods and tools to investigate and to quantify the connection between climate, cryosphere (permafrost, glaciers, snow) and geomorphodynamics. In this presentation, we describe the concepts and system architecture used both for the wireless sensor network as well as for data management and processing. Furthermore, we will discuss the experience gained in over a decade of planning, installing and operating large deployments on field sites spread across a large part of the Swiss and French Alps and applications ranging from academic, experimental research campaigns, long-term monitoring and natural hazard warning in collaboration with government authorities and local industry partners. Reference http://www.permasense.ch Online Open Data Access http://data.permasense.ch

  3. Identification of Jets Containing $b$-Hadrons with Recurrent Neural Networks at the ATLAS Experiment

    CERN Document Server

    The ATLAS collaboration

    2017-01-01

    A novel $b$-jet identification algorithm is constructed with a Recurrent Neural Network (RNN) at the ATLAS experiment at the CERN Large Hadron Collider. The RNN based $b$-tagging algorithm processes charged particle tracks associated to jets without reliance on secondary vertex finding, and can augment existing secondary-vertex based taggers. In contrast to traditional impact-parameter-based $b$-tagging algorithms which assume that tracks associated to jets are independent from each other, the RNN based $b$-tagging algorithm can exploit the spatial and kinematic correlations between tracks which are initiated from the same $b$-hadrons. This new approach also accommodates an extended set of input variables. This note presents the expected performance of the RNN based $b$-tagging algorithm in simulated $t \\bar t$ events at $\\sqrt{s}=13$ TeV.

  4. Assessing computational genomics skills: Our experience in the H3ABioNet African bioinformatics network.

    Directory of Open Access Journals (Sweden)

    C Victor Jongeneel

    2017-06-01

    Full Text Available The H3ABioNet pan-African bioinformatics network, which is funded to support the Human Heredity and Health in Africa (H3Africa program, has developed node-assessment exercises to gauge the ability of its participating research and service groups to analyze typical genome-wide datasets being generated by H3Africa research groups. We describe a framework for the assessment of computational genomics analysis skills, which includes standard operating procedures, training and test datasets, and a process for administering the exercise. We present the experiences of 3 research groups that have taken the exercise and the impact on their ability to manage complex projects. Finally, we discuss the reasons why many H3ABioNet nodes have declined so far to participate and potential strategies to encourage them to do so.

  5. OPERATING SYSTEM FOR WIRELESS SENSOR NETWORKS AND AN EXPERIMENT OF PORTING CONTIKIOS TO MSP430 MICROCONTROLLER

    Directory of Open Access Journals (Sweden)

    Thang Vu Chien

    2012-07-01

    Full Text Available Wireless Sensor Networks (WSNs consist of a large number of sensor nodes, and are used for various applications such as building monitoring, environment control, wild-life habitat monitoring, forest fire detection, industry automation, military, security, and health-care. Each sensor node needs an operating system (OS that can control the hardware, provide hardware abstraction to application software, and fill in the gap between applications and the underlying hardware. In this paper, researchers present OS for WSNs and an experiment of porting contikiOS to MSP430 microcontroller which is very popular in many hardware platforms for WSNs. Researchers begin by presenting the major issues for the design of OS for WSNs. Then, researchers examine some popular operating systems for WSNs including TinyOS, ContikiOS, and LiteOS. Finally, researchers present an experiment of porting ContikiOS to MSP430 microcontroller. Wireless Sensor Networks (WSNs terdiri dari sejumlah besar sensor nodes, dan digunakan untuk berbagai aplikasi seperti pemantauan gedung, pengendalian lingkungan, pemantauan kehidupan habitat liar, deteksi kebakaran hutan, otomatisasi industri, militer, keamanan, dan kesehatan. Setiap sensor nodememerlukan sistem operasi (SO yang dapat mengontrol hardware, menyediakan abstraksi hardware untuk aplikasi perangkat lunak, dan mengisi kesenjangan antara aplikasi dan hardware. Dalam penelitian ini, peneliti menyajikan SO untuk WSNs dan percobaan dari port contikiOS untuk MSP430 mikrokontroler yang sangat populer di platformhardware untuk WSNs. Peneliti memulai dengan menghadirkan isu utama yaitu desain SO untuk WSNs. Lalu, penelitimemeriksa beberapa sistem operasi populer untuk WSNs, termasuk TinyOS, ContikiOS, dan LiteOS. Akhirnya penelitimenyajikan sebuah percobaan dari port ContikiOS untuk MSP430 mikrokontroler.

  6. Event classification with the electronic detectors of the OPERA experiment using neural networks

    Energy Technology Data Exchange (ETDEWEB)

    Hierholzer, Martin C.

    2012-02-15

    The OPERA experiment searches for {nu}{sub {mu}} <-> {nu}{sub {tau}} oscillations in appearance mode. It uses the emulsion cloud chamber (ECC) technique for a high spatial resolution combined with on-line components for event localisation and muon identification. The analysis of events in an ECC detector takes considerable time, especially in case of {nu}{sub {tau}}/{nu}{sub e} candidate events. A ranking of events by a probability for being a {nu}{sub {tau}}/{nu}{sub e} event can speed up the analysis of the OPERA experiment. An algorithm for such an event ranking based on a classification-type neural network is presented in this thesis. Almost all candidate events can be found within the first 30% of the analysed events if the described ranking is applied. This event ranking is currently applied for testing purposes by the OPERA collaboration, a decision on a full application for the whole analysis is pending. A similar neural network is used for discrimination between neutral and charged current events. This is used to observe neutrino oscillations in disappearance mode with the on-line components of the OPERA detector by measuring the energy dependence of the fraction of neutral current interactions. The confidence level of the observed oscillation effect is 87%. Assuming full mixing, the mass splitting has been determined to vertical stroke {delta}m{sup 2}{sub 32} vertical stroke =2.8{sub -1.7}{sup +1.4}.10{sup -3}eV{sup 2}.

  7. Optimal design of stimulus experiments for robust discrimination of biochemical reaction networks.

    Science.gov (United States)

    Flassig, R J; Sundmacher, K

    2012-12-01

    Biochemical reaction networks in the form of coupled ordinary differential equations (ODEs) provide a powerful modeling tool for understanding the dynamics of biochemical processes. During the early phase of modeling, scientists have to deal with a large pool of competing nonlinear models. At this point, discrimination experiments can be designed and conducted to obtain optimal data for selecting the most plausible model. Since biological ODE models have widely distributed parameters due to, e.g. biologic variability or experimental variations, model responses become distributed. Therefore, a robust optimal experimental design (OED) for model discrimination can be used to discriminate models based on their response probability distribution functions (PDFs). In this work, we present an optimal control-based methodology for designing optimal stimulus experiments aimed at robust model discrimination. For estimating the time-varying model response PDF, which results from the nonlinear propagation of the parameter PDF under the ODE dynamics, we suggest using the sigma-point approach. Using the model overlap (expected likelihood) as a robust discrimination criterion to measure dissimilarities between expected model response PDFs, we benchmark the proposed nonlinear design approach against linearization with respect to prediction accuracy and design quality for two nonlinear biological reaction networks. As shown, the sigma-point outperforms the linearization approach in the case of widely distributed parameter sets and/or existing multiple steady states. Since the sigma-point approach scales linearly with the number of model parameter, it can be applied to large systems for robust experimental planning. An implementation of the method in MATLAB/AMPL is available at http://www.uni-magdeburg.de/ivt/svt/person/rf/roed.html. flassig@mpi-magdeburg.mpg.de Supplementary data are are available at Bioinformatics online.

  8. Optimal design of stimulus experiments for robust discrimination of biochemical reaction networks

    Science.gov (United States)

    Flassig, R. J.; Sundmacher, K.

    2012-01-01

    Motivation: Biochemical reaction networks in the form of coupled ordinary differential equations (ODEs) provide a powerful modeling tool for understanding the dynamics of biochemical processes. During the early phase of modeling, scientists have to deal with a large pool of competing nonlinear models. At this point, discrimination experiments can be designed and conducted to obtain optimal data for selecting the most plausible model. Since biological ODE models have widely distributed parameters due to, e.g. biologic variability or experimental variations, model responses become distributed. Therefore, a robust optimal experimental design (OED) for model discrimination can be used to discriminate models based on their response probability distribution functions (PDFs). Results: In this work, we present an optimal control-based methodology for designing optimal stimulus experiments aimed at robust model discrimination. For estimating the time-varying model response PDF, which results from the nonlinear propagation of the parameter PDF under the ODE dynamics, we suggest using the sigma-point approach. Using the model overlap (expected likelihood) as a robust discrimination criterion to measure dissimilarities between expected model response PDFs, we benchmark the proposed nonlinear design approach against linearization with respect to prediction accuracy and design quality for two nonlinear biological reaction networks. As shown, the sigma-point outperforms the linearization approach in the case of widely distributed parameter sets and/or existing multiple steady states. Since the sigma-point approach scales linearly with the number of model parameter, it can be applied to large systems for robust experimental planning. Availability: An implementation of the method in MATLAB/AMPL is available at http://www.uni-magdeburg.de/ivt/svt/person/rf/roed.html. Contact: flassig@mpi-magdeburg.mpg.de Supplementary information: Supplementary data are are available at

  9. Experiment-Based Sensitivity Analysis of Scaled Carbon-Fiber-Reinforced Elastomeric Isolators in Bonded Applications

    Directory of Open Access Journals (Sweden)

    Farshad Hedayati Dezfuli

    2016-01-01

    Full Text Available Fiber-reinforced elastomeric isolators (FREIs are a new type of elastomeric base isolation systems. Producing FREIs in the form of long laminated pads and cutting them to the required size significantly reduces the time and cost of the manufacturing process. Due to the lack of adequate information on the performance of FREIs in bonded applications, the goal of this study is to assess the performance sensitivity of 1/4-scale carbon-FREIs based on the experimental tests. The scaled carbon-FREIs are manufactured using a fast cold-vulcanization process. The effect of several factors including the vertical pressure, the lateral cyclic rate, the number of rubber layers, and the thickness of carbon fiber-reinforced layers are explored on the cyclic behavior of rubber bearings. Results show that the effect of vertical pressure on the lateral response of base isolators is negligible. However, decreasing the cyclic loading rate increases the lateral flexibility and the damping capacity. Additionally, carbon fiber-reinforced layers can be considered as a minor source of energy dissipation.

  10. Sensitive Analysis for the Efficiency of a Parabolic Trough Solar Collector Based on Orthogonal Experiment

    Directory of Open Access Journals (Sweden)

    Xiaoyan Liu

    2015-01-01

    Full Text Available A multitude of the researches focus on the factors of the thermal efficiency of a parabolic trough solar collector, that is, the optical-thermal efficiency. However, it is limited to a single or double factors for available system. The aim of this paper is to investigate the multifactors effect on the system’s efficiency in cold climate region. Taking climatic performance into account, an average outlet temperature of LS-2 collector has been simulated successfully by coupling SolTrace software with CFD software. Effects of different factors on instantaneous efficiency have been determined by orthogonal experiment and single factor experiment. After that, the influence degree of different factors on the collector instantaneous efficiency is obtained clearly. The results show that the order of effect extent for average maximal deviation of each factor is inlet temperature, solar radiation intensity, diameter, flow rate, condensation area, pipe length, and ambient temperature. The encouraging results will provide a reference for the exploitation and utilization of parabolic trough solar collector in cold climate region.

  11. Experience with trabectedin + pegylated liposomal doxorubicin for recurrent platinum-sensitive ovarian cancer unsuited to platinum rechallenge.

    Science.gov (United States)

    Colombo, Nicoletta; Hardy-Bessard, Anne-Claire; Ferrandina, Gabriella; Marth, Christian; Romero, Ignacio

    2016-11-01

    As most patients with ovarian cancer experience multiple remissions and relapses, oncologists must prepare ahead for long-term treatment. While platinum-based regimens are standard of care for platinum-sensitive recurrence, there are circumstances in which platinum rechallenge is not the best approach. These situations include patients with limited sensitivity to platinum; patients with residual toxicity from previous platinum therapy; and patients at risk of developing hypersensitivity reactions. An alternative regimen for these patients is the non-platinum combination of trabectedin + pegylated liposomal doxorubicin (PLD). Areas covered: In this review, case studies are presented to illustrate how careful strategic planning, in terms of therapeutic choices and optimal sequencing, can achieve good outcomes in difficult-to-treat patients. Expert commentary: Advantages with use of trabectedin + PLD in selected patients with platinum-sensitive recurrent ovarian cancer include additional time to recover from platinum-related toxicities, avoidance of hypersensitivity reactions, and the 'sequence effect' by which trabectedin may enhance response to next platinum and prolong survival.

  12. Assessing stakeholder's experience and sensitivity on key issues for the economic growth of organic aquaculture production

    DEFF Research Database (Denmark)

    Lembo, Giuseppe; Jokumsen, Alfred; Spedicato, Maria Teresa

    2018-01-01

    , and specifically, of the aquaculture system. A survey focused on the current EU regulatory framework was carried out to elicit stakeholders’ preferences, knowledge and experience on key issues for the development of organic aquaculture, supported by science-based regulations. The survey was completed by 65...... stakeholders belonging to several categories, and it was supported by the implementation of the Analytic Hierarchy Process method. Stakeholders’ preferences were elicited on organic production methods and control systems, the quality of the environment and organic products, fish health and welfare. The views...... expressed by the participants revealed both competence and awareness, despite the complexity of the subject. Several ideas and useful suggestions emerged regarding unresolved technical issues. In addition, the need for a targeted communication strategy on the quality of organic aquaculture products...

  13. Towards unambiguous assignment of methyl-containing residues by double and triple sensitivity-enhanced HCCmHm-TOCSY experiments

    Energy Technology Data Exchange (ETDEWEB)

    Wuertz, Peter; Hellman, Maarit; Tossavainen, Helena; Permi, Perttu [University of Helsinki, Program in Structural Biology and Biophysics, Institute of Biotechnology/NMR Laboratory (Finland)], E-mail: Perttu.Permi@helsinki.fi

    2006-09-15

    Chemical shift assignment of methyl-containing residues is essential in protein NMR spectroscopy, as these residues are abundant in protein interiors and provide the vast majority of long-range NOE connectivities for structure determination. These residues also constitute an integral part of hydrophobic cavities, the surroundings for many enzymatic reactions. Here we present a powerful strategy for the assignment of methyl-containing residues in a uniformly {sup 13}C/{sup 15}N double labeled protein sample. The approach is based on novel four-dimensional HCCmHm-TOCSY experiments, two of them utilizing gradient selection and sensitivity enhancement in all three indirectly detected dimensions. Regardless of the number of dimensions, the proposed experiments can be executed using only one transient per FID, providing outstanding resolution and sensitivity. A complete assignment of the 51 methyl-containing residues in the 16 kDa Mus musculus coactosin was accomplished using a four-dimensional HCCmHm-TOCSY spectrum recorded in 16 hours.

  14. Hydrogels based on interpenetrating network of chitosan and polyvinyl pyrrolidone for pH-sensitive delivery of repaglinide.

    Science.gov (United States)

    Vaghani, Subhash S; Patel, Madhabhai M

    2011-06-01

    The aim of this study was to develop a pH-sensitive chitosan/polyvinyl pyrrolidone (PVP) based controlled drug release system for repaglinide. The hydrogels were synthesised by crosslinking chitosan and PVP blend with glutaraldehyde to form a semi-interpenetrating polymer network (semi-IPN). These semi-IPNs were studied for their content uniformity, swelling index (SI), mucoadhesion, wettability, in vitro release and their release kinetics. The hydrogels showed more than 95% loading of repaglinide. These hydrogels showed high swelling and mucoadhesion under acidic conditions. The swelling was found due to the protonation of a primary amino group on chitosan. In acidic condition chitosan was ionized, and adhesion occurred between the positively charged chitosan and the negatively charged mucus. In the physiological condition less swelling was noticed. In vitro release study revealed that formulation containing chitosan (2% w/v) and PVP (4% w/v) in the ratio of 14:6 w/w showed complete drug release after 12h. Release profile showed that all the formulations followed non-fickian diffusion mechanism (diffusion coupled with swelling). Fourier transform infrared (FTIR) spectroscopic analysis revealed proper crosslinking of polymer and formation of semi-IPN as well as presence of drug in the formulation. Differential scanning calorimetry (DSC) and powder x-ray diffraction (p-XRD) study revealed the presence of repaglinide in crystalline form in the formulations. The surface morphology of semi-IPN was studied before and after dissolution in simulated gastric fluid (SGF, pH 1.2) which indicated generation of open channel-like structure in hydrogel after dissolution. The results of study suggest that semi-IPNs of chitosan/PVP are potent candidates for delivery of repaglinide in acidic environment.

  15. Sensitivity experiments on the response of Vb cyclones to sea surface temperature and soil moisture changes

    Directory of Open Access Journals (Sweden)

    M. Messmer

    2017-07-01

    Full Text Available Extratropical cyclones of type Vb, which develop over the western Mediterranean and move northeastward, are major natural hazards that are responsible for heavy precipitation over central Europe. To gain further understanding in the governing processes of these Vb cyclones, the study explores the role of soil moisture and sea surface temperature (SST and their contribution to the atmospheric moisture content. Thereby, recent Vb events identified in the ERA-Interim reanalysis are dynamically downscaled with the Weather Research and Forecasting (WRF model. Results indicate that a mean high-impact summer Vb event is mostly sensitive to an increase in the Mediterranean SSTs and rather insensitive to Atlantic SSTs and soil moisture changes. Hence, an increase of +5 K in Mediterranean SSTs leads to an average increase of 24 % in precipitation over central Europe. This increase in precipitation is mainly induced by larger mean upward moisture flux over the Mediterranean with increasing Mediterranean SSTs. This further invokes an increase in latent energy release, which leads to an increase in atmospheric instability, i.e. in convective available potential energy. Both the increased availability of atmospheric moisture and the increased instability of the atmosphere, which is able to remove extra moisture from the atmosphere due to convective processes, are responsible for the strong increase in precipitation over the entire region influenced by Vb events. Precipitation patterns further indicate that a strong increase in precipitation is found at the eastern coast of the Adriatic Sea for increased Mediterranean SSTs. This premature loss in atmospheric moisture leads to a significant decrease in atmospheric moisture transport to central Europe and the northeastern flanks of the Alpine mountain chain. This leads to a reduction in precipitation in this high-impact region of the Vb event for an increase in Mediterranean SSTs of +5 K. Furthermore, the

  16. Sensitivity experiments on the response of Vb cyclones to sea surface temperature and soil moisture changes

    Science.gov (United States)

    Messmer, Martina; José Gómez-Navarro, Juan; Raible, Christoph C.

    2017-07-01

    Extratropical cyclones of type Vb, which develop over the western Mediterranean and move northeastward, are major natural hazards that are responsible for heavy precipitation over central Europe. To gain further understanding in the governing processes of these Vb cyclones, the study explores the role of soil moisture and sea surface temperature (SST) and their contribution to the atmospheric moisture content. Thereby, recent Vb events identified in the ERA-Interim reanalysis are dynamically downscaled with the Weather Research and Forecasting (WRF) model. Results indicate that a mean high-impact summer Vb event is mostly sensitive to an increase in the Mediterranean SSTs and rather insensitive to Atlantic SSTs and soil moisture changes. Hence, an increase of +5 K in Mediterranean SSTs leads to an average increase of 24 % in precipitation over central Europe. This increase in precipitation is mainly induced by larger mean upward moisture flux over the Mediterranean with increasing Mediterranean SSTs. This further invokes an increase in latent energy release, which leads to an increase in atmospheric instability, i.e. in convective available potential energy. Both the increased availability of atmospheric moisture and the increased instability of the atmosphere, which is able to remove extra moisture from the atmosphere due to convective processes, are responsible for the strong increase in precipitation over the entire region influenced by Vb events. Precipitation patterns further indicate that a strong increase in precipitation is found at the eastern coast of the Adriatic Sea for increased Mediterranean SSTs. This premature loss in atmospheric moisture leads to a significant decrease in atmospheric moisture transport to central Europe and the northeastern flanks of the Alpine mountain chain. This leads to a reduction in precipitation in this high-impact region of the Vb event for an increase in Mediterranean SSTs of +5 K. Furthermore, the intensity of the Vb

  17. [Networks of experiences on community health as an information system in health promotion: lessons learned in Aragon (Spain)].

    Science.gov (United States)

    Gállego-Diéguez, Javier; Aliaga Traín, Pilar; Benedé Azagra, Carmen Belén; Bueno Franco, Manuel; Ferrer Gracia, Elisa; Ipiéns Sarrate, José Ramón; Muñoz Nadal, Pilar; Plumed Parrilla, Manuela; Vilches Urrutia, Begoña

    2016-11-01

    Networks of community health experiences promote interaction and knowledge management in health promotion among their participants. These networks integrate both professionals and social agents who work directly on the ground in small environments, with defined objectives and inclusion criteria and voluntary participation. In this article, networks in Aragon (Spain) are reviewed in order to analyse their role as an information system. The Health Promotion Projects Network of Aragon (Red Aragonesa de Proyectos de Promoción de la Salud, RAPPS) was launched in 1996 and currently includes 73 projects. The average duration of projects is 12.7 years. RAPPS interdisciplinary teams involve 701 people, of which 89.6% are professionals and 10.6% are social agents. The Aragon Health Promoting Schools Network (Red Aragonesa de Escuelas Promotoras de Salud, RAEPS) integrates 134 schools (24.9% of Aragon). The schools teams involve 829 teachers and members of the school community, students (35.2%), families (26.2%) and primary care health professionals (9.8%). Experiences Networks boost citizen participation, have an influence in changing social determinants and contribute to the formulation of plans and regional strategies. Networks can provide indicators for a health promotion information and monitoring system on: capacity building services in the territory, identifying assets and models of good practice, cross-sectoral and equity initiatives. Experiences Networks represent an opportunity to create a health promotion information system, systematising available information and establishing quality criteria for initiatives. Copyright © 2016 SESPAS. Publicado por Elsevier España, S.L.U. All rights reserved.

  18. A FPGA-based Network Interface Card with GPUDirect enabling realtime GPU computing in HEP experiments

    CERN Document Server

    Lonardo, Alessandro; Ammendola, Roberto; Biagioni, Andrea; Cotta Ramusino, Angelo; Fiorini, Massimiliano; Frezza, Ottorino; Lamanna, Gianluca; Lo Cicero, Francesca; Martinelli, Michele; Neri, Ilaria; Paolucci, Pier Stanislao; Pastorelli, Elena; Pontisso, Luca; Rossetti, Davide; Simeone, Francesco; Simula, Francesco; Sozzi, Marco; Tosoratto, Laura; Vicini, Piero

    2015-01-01

    The capability of processing high bandwidth data streams in real-time is a computational requirement common to many High Energy Physics experiments. Keeping the latency of the data transport tasks under control is essential in order to meet this requirement. We present NaNet, a FPGA-based PCIe Network Interface Card design featuring Remote Direct Memory Access towards CPU and GPU memories plus a transport protocol offload module characterized by cycle-accurate upper-bound handling. The combination of these two features allows to relieve almost entirely the OS and the application from data tranfer management, minimizing the unavoidable jitter effects associated to OS process scheduling. The design currently supports one GbE (1000Base-T) and three custom 34 Gbps APElink I/O channels, but four-channels 10GbE (10Base-R) and 2.5 Gbps deterministic latency KM3link versions are being implemented. Two use cases of NaNet will be discussed: the GPU-based low level trigger for the RICH detector in the NA62 experiment an...

  19. SHAME EXPERIENCES AND PROBLEMATIC SOCIAL NETWORKING SITES USE: AN UNEXPLORED ASSOCIATION

    Directory of Open Access Journals (Sweden)

    Silvia Casale

    2017-02-01

    Full Text Available Objective: The current study investigates the main and indirect effects of shame experiences and perceived benefits of computer-mediated communication (CMC compared with face-to-face communication, on Problematic Social Networking Sites Use (PSNSU. In particular, a model in which perceived benefits of CMC (i.e. escapism, control over self-presentation, and approval/acceptance mediate the association between shame and PSNSU was tested. Method: A sample of 590 undergraduate students (mean age = 22.29 + 2.079; females = 53.2% completed measures of shame experiences, perceived benefits of CMC and PSNSU. Results: The assessed structural model produced adequate fit to the data (χ2= 352.99; df = 92; p <.001; RMSEA [90% CI] =.07 [.06-.08]; CFI = .97; SRMR = .06. Variables accounted for 50% of the variance in PSNSU. A partial mediation model in which shame predicted PSNSU levels through the perceived benefits of CMC was found. A direct relationship between shame and PSNSU was also detected. Conclusions: The current study highlights how feelings of shame can contribute to problematic use of SNS and emphasizes the necessity of taking into account the perceived benefits of CMC when exploring psychological risk factors for PSNSU.

  20. Evolving a Network of Networks: The Experience of Partnerships in the National Digital Information Infrastructure and Preservation Program

    Directory of Open Access Journals (Sweden)

    Martha Anderson

    2008-08-01

    Full Text Available The National Digital Information Infrastructure and Preservation Program (NDIIPP was initiated in December 2000 when the U.S. Congress authorized the Library of Congress to work with a broad range of institutions to develop a national strategy for the preservation of at-risk digital content. Guided by a strategy of collaboration and iteration, the Library of Congress began the formation of a national network of partners dedicated to collecting and preserving important born-digital information. Over the last six years, the Library and its partners have been engaged in learning through action that has resulted in an evolving understanding of the most appropriate roles and functions for a national network of diverse stakeholders. The emerging network is complex and inclusive of a variety of stakeholders; content producers, content stewards and service providers from the public and private sectors. Lessons learned indicate that interoperability is a challenge in all aspects of collaborative work.

  1. Developmental precursors of social brain networks: the emergence of attentional and cortical sensitivity to facial expressions in 5 to 7 months old infants.

    Directory of Open Access Journals (Sweden)

    Santeri Yrttiaho

    Full Text Available Biases in attention towards facial cues during infancy may have an important role in the development of social brain networks. The current study used a longitudinal design to examine the stability of infants' attentional biases towards facial expressions and to elucidate how these biases relate to emerging cortical sensitivity to facial expressions. Event-related potential (ERP and attention disengagement data were acquired in response to the presentation of fearful, happy, neutral, and phase-scrambled face stimuli from the same infants at 5 and 7 months of age. The tendency to disengage from faces was highly consistent across both ages. However, the modulation of this behavior by fearful facial expressions was uncorrelated between 5 and 7 months. In the ERP data, fear-sensitive activity was observed over posterior scalp regions, starting at the latency of the N290 wave. The scalp distribution of this sensitivity to fear in ERPs was dissociable from the topography of face-sensitive modulation within the same latency range. While attentional bias scores were independent of co-registered ERPs, attention bias towards fearful faces at 5 months of age predicted the fear-sensitivity in ERPs at 7 months of age. The current results suggest that the attention bias towards fear could be involved in the developmental tuning of cortical networks for social signals of emotion.

  2. The role of autobiographical memory networks in the experience of negative emotions: how our remembered past elicits our current feelings.

    Science.gov (United States)

    Philippe, Frederick L; Koestner, Richard; Lecours, Serge; Beaulieu-Pelletier, Genevieve; Bois, Katy

    2011-12-01

    The present research examined the role of autobiographical memory networks on negative emotional experiences. Results from 2 studies found support for an active but also discriminant role of autobiographical memories and their related networked memories on negative emotions. In addition, in line with self-determination theory, thwarting of the psychological needs for competence, autonomy, and relatedness was found to be the critical component of autobiographical memory affecting negative emotional experiences. Study 1 revealed that need thwarting in a specific autobiographical memory network related to the theme of loss was positively associated with depressive negative emotions, but not with other negative emotions. Study 2 showed within a prospective design a differential predictive validity between 2 autobiographical memory networks (an anger-related vs. a guilt-related memory) on situational anger reactivity with respect to unfair treatment. All of these results held after controlling for neuroticism (Studies 1 and 2), self-control (Study 2), and for the valence (Study 1) and emotions (Study 2) found in the measured autobiographical memory network. These findings highlight the ongoing emotional significance of representations of need thwarting in autobiographical memory networks. (c) 2011 APA, all rights reserved.

  3. Knowledge sharing Network analysis and its relationship with the experience and education of librarians at Ferdowsi University of Mashhad

    Directory of Open Access Journals (Sweden)

    Maryam Salami

    2017-03-01

    Full Text Available As human resources are important resources in organization, it is important for organizations to use knowledge organization of human resources. Thus managing and sharing knowledge in organizations is so important. Libraries as well service-oriented and knowledge-based organizations, librarians’ contribution of knowledge management is important. The study tries to determine Ferdowsi University of Mashhad librarians’ participation in the process of knowledge sharing by knowledge sharing network analysis method. The application used for social network analysis is UCINET6. Determining the degree of centralization in the network of knowledge sharing can also help to detect factors may influence it. In this study, the degree of centralization in the network of knowledge sharing communicating with the librarians' qualifications and work experiences were tested. It is also determined the degree centralization of the whole of the knowledge sharing network with 26.76% that is not so satisfactory.  The results show that despite the positive relationship between level of education and the centrality of people, the experience no significant relationship. Statistically, there is also no significant difference between men and women in knowledge sharing degrees of librarians in Ferdowsi University of Mashhad. At the end, according to the results of this research some suggestions are given to increase degrees of knowledge sharing of librarians and generally knowledge sharing degree of the network knowledge sharing.

  4. Sensitivity of Arctic Permafrost Carbon in the Mackenzie River Basin: A substrate addition and incubation experiment

    Science.gov (United States)

    Hedgpeth, A.; Beilman, D.; Crow, S. E.

    2014-12-01

    Arctic soil organic matter (SOM) mineralization processes are fundamental to the functioning of high latitude soils in relation to nutrients, stability, and feedbacks to atmospheric CO2 and climate. The arctic permafrost zone covers 25% of the northern hemisphere and contains 1672Pg of soil carbon (C). 88% of this C currently resides in frozen soils that are vulnerable to environmental change. For instance, arctic growing seasons may be lengthened, resulting in an increase in plant productivity and rate of below ground labile C inputs as root exudates. Understanding controls on Arctic SOM dynamics requires recognition that labile C inputs have the potential to significantly affect mineralization of previously stable SOM, also known as 'priming effects'. We conducted a substrate addition incubation experiment to quantify and compare respiration in highly organic (42-48 %C) permafrost soils along a north-south transect in western Canada. Near surface soils (10-20 cm) were collected from permafrost peatland sites in the Mackenzie River Basin from 69.2-62.6°N. The surface soils are fairly young (Δ14C values > -140.0) and can be assumed to contain relatively reactive soil carbon. To assess whether addition of labile substrate alters SOM decomposition dynamics, 4.77-11.75 g of permafrost soil were spiked with 0.5 mg D-glucose g-1 soil and incubated at 5°C. A mass balance approach was used to determin substrate-induced respiration and preliminary results suggest a potential for positive priming in these C-rich soils. Baseline respiration rates from the three sites were similar (0.067-0.263 mg CO2 g-1 soil C) yet show some site-specific trends. The rate at which added substrate was utilized within these soils suggests that other factors besides temperature and soil C content are controlling substrate consumption and its effect on SOM decomposition. Microbial activity can be stimulated by substrate addition to such an extent that SOM turnover is enhanced, suggesting that

  5. Environment sensitization through arts: an experience with communities along Amazon rivers

    Energy Technology Data Exchange (ETDEWEB)

    Freitas, Wanderleia Isabel P. de; Gusmao, Dulce Milena Almeida [PETROBRAS S.A., Rio de Janeiro, RJ (Brazil)

    2009-07-01

    In Brazil, the deforestation, pollution, losses in historic and cultural patrimony are each time more common in communities which, due to the great distances from urban centers, lack of any level of information. Normally, in these communities, theaters do not exist, nor local cinemas or places where people can have access to any type of art and culture. In this context, the Amazon suffers from the same problems than other regions in Brazil, however allied to logistic difficulties and other local specificities. That way, this work is about an experience lived in the Urucu-Coari-Manaus gas pipeline construction and assembly process, in which 18 communities were involved in a work of Environmental Education through arts: music, theater, movies, and others. In those communities there is great disinformation or distortion regarding programs and environmental plans from Urucu-Coari-Manaus gas pipeline, mainly due to the distance from urban centers and lack of communication vehicles. But this initiative did not come from an obligation or legal recommendations, but from a necessity to reach this public using an assertive communication. This work's specific goals were: To use the interpenetration between art and education and the playful, creative and humorous language of specific artistic interventions, adjusted to that public and its peculiarities, in order to lead the dialogue between different knowledge, that is, between traditional culture and environmental concepts paved in studies and scientific data, and to spread Urucu-Manaus gas pipeline environmental programs; To arise, in the artistic interventions, that specific public's participation and integration, always focusing the environmental message and the respect for the Amazonian culture; To value, in all artistic interventions, people's traditional knowledge, the Amazonian environment and, mainly, the importance of each local inhabitant for that environment's conservation, important for us all

  6. Capsule endoscopy in a network cooperation: assessment of the experience in 822 patients.

    Science.gov (United States)

    Farnbacher, Michael Julius; Keles, Murat; Meier, Michael; Hagel, Alexander; Schneider, Thomas

    2013-09-01

    Capsule endoscopy (CE) is firmly established as a standard procedure in the diagnostic algorithm of occult or obscure gastrointestinal bleeding and Crohn's disease. Despite its excellent diagnostic yield, missing expertise, reading time and financial expenditure limit an area-wide availability. A multicentric cooperation might compensate these disadvantages. CE device was bought by a central hospital (CH). Requested equipment is transported to the network partner (NP) and the procedure performed at the spot in personal responsibility. Video reading is exclusively done in the CH. Within 10 years, 822 CE (438 m., 384 f.; 63 ± 17 (13-92) years) were performed by 18 cooperating gastroenterological departments. 587/822 (71%) CE were done at NP, 235/822 (29%) in the CH. Between 2002 (n = 39) and 2011 (n = 123) the annual number of CE increased threefold. 95% of the capital investment in each cooperating hospital could be avoided by sharing one workstation within the network. Leading indication for CE was suspected mid-GI-bleeding (80%). Mean latencies between requested date and actual examination were 0 and between equipment's return and report 2 days. 45/191(24%) flexible enteroscopies performed in the CH followed CE findings from NP. Our 10 years experience show that mobile use of CE is feasible providing quality parameters similar to a single center solution, increases the number of CE investigations, therefore, improves reading expertise and enables both an area-wide and economic offer for this technique. Additionally, patients with the need for invasive enteroscopy are identified and attracted to that NP who provides an invasive SB endocopy device.

  7. Smartphones vs PCs: Does the Device Affect the Web Survey Experience and the Measurement Error for Sensitive Topics? - A Replication of the Mavletova & Couper’s 2013 Experiment

    Directory of Open Access Journals (Sweden)

    Daniele Toninelli

    2016-08-01

    Full Text Available More and more respondents use mobile devices to complete web surveys. These devices have different characteristics, if compared to PCs (e.g. smaller screen sizes and higher portability. These characteristics can affect the survey responses, mostly when a questionnaire includes sensitive questions. This topic was already studied by Mavletova and Couper (2013, through a two-wave experiment comparing PCs and mobile devices results for the same respondents in a Russian opt-in panel. We replicated this cross-over design, focusing on an opt-in panel for Spain, involving 1,800 panellists and comparing PCs and smartphones. Our results support most of Mavletova and Couper’s (2013 findings (e.g. generally the used device does not significantly affect the reporting of sensitive information, confirming their robustness over the two studied countries. For other results (e.g. trust in data confidentiality, we found differences that can be justified by the diverse context/culture or by the quick changes that are still characterizing the mobile web survey participation.

  8. Selective Narrowing of Social Networks across Adulthood is Associated with Improved Emotional Experience in Daily Life

    Science.gov (United States)

    English, Tammy; Carstensen, Laura L.

    2014-01-01

    Past research has documented age differences in the size and composition of social networks that suggest that networks grow smaller with age and include an increasingly greater proportion of well-known social partners. According to socioemotional selectivity theory, such changes in social network composition serve an antecedent emotion regulatory…

  9. The Development and Validation of the Social Networking Experiences Questionnaire: A Measure of Adolescent Cyberbullying and Its Impact.

    Science.gov (United States)

    Dredge, Rebecca; Gleeson, John; Garcia, Xochitl de la Piedad

    2015-01-01

    The measurement of cyberbullying has been marked by several inconsistencies that lead to difficulties in cross-study comparisons of the frequency of occurrence and the impact of cyberbullying. Consequently, the first aim of this study was to develop a measure of experience with and impact of cyberbullying victimization in social networking sites in adolescents. The second aim was to investigate the psychometric properties of a purpose-built measure (Social Networking Experiences Questionnaire [SNEQ]). Exploratory factor analysis on 253 adolescent social networking sites users produced a six-factor model of impact. However, one factor was removed because of low internal consistency. Cronbach's alpha was higher than .76 for the victimization and remaining five impact subscales. Furthermore, correlation coefficients for the Victimization scale and related dimensions showed good construct validity. The utility of the SNEQ for victim support personnel, research, and cyberbullying education/prevention programs is discussed.

  10. Experience with low-cost telemedicine in three different settings. Recommendations based on a proposed framework for network performance evaluation

    Science.gov (United States)

    Wootton, Richard; Vladzymyrskyy, Anton; Zolfo, Maria; Bonnardot, Laurent

    2011-01-01

    Background Telemedicine has been used for many years to support doctors in the developing world. Several networks provide services in different settings and in different ways. However, to draw conclusions about which telemedicine networks are successful requires a method of evaluating them. No general consensus or validated framework exists for this purpose. Objective To define a basic method of performance measurement that can be used to improve and compare teleconsultation networks; to employ the proposed framework in an evaluation of three existing networks; to make recommendations about the future implementation and follow-up of such networks. Methods Analysis based on the experience of three telemedicine networks (in operation for 7–10 years) that provide services to doctors in low-resource settings and which employ the same basic design. Findings Although there are many possible indicators and metrics that might be relevant, five measures for each of the three user groups appear to be sufficient for the proposed framework. In addition, from the societal perspective, information about clinical- and cost-effectiveness is also required. The proposed performance measurement framework was applied to three mature telemedicine networks. Despite their differences in terms of activity, size and objectives, their performance in certain respects is very similar. For example, the time to first reply from an expert is about 24 hours for each network. Although all three networks had systems in place to collect data from the user perspective, none of them collected information about the coordinator's time required or about ease of system usage. They had only limited information about quality and cost. Conclusion Measuring the performance of a telemedicine network is essential in understanding whether the network is working as intended and what effect it is having. Based on long-term field experience, the suggested framework is a practical tool that will permit

  11. The cost of sensitive response and accurate adaptation in networks with an incoherent type-1 feed-forward loop.

    Science.gov (United States)

    Lan, Ganhui; Tu, Yuhai

    2013-10-06

    The incoherent type-1 feed-forward loop (I1-FFL) is ubiquitous in biological regulatory circuits. Although much is known about the functions of the I1-FFL motif, the energy cost incurred in the network and how it affects the performance of the network have not been investigated. Here, we study a generic I1-FFL enzymatic reaction network modelled after the GEF-GAP-Ras pathway responsible for chemosensory adaptation in eukaryotic cells. Our analysis shows that the I1-FFL network always operates out of equilibrium. Continuous energy dissipation is necessary to drive an internal phosphorylation-dephosphorylation cycle that is crucial in achieving strong short-time response and accurate long-time adaptation. In particular, we show quantitatively that the energy dissipated in the I1-FFL network is used (i) to increase the system's initial response to the input signals; (ii) to enhance the adaptation accuracy at steady state; and (iii) to expand the range of such accurate adaptation. Moreover, we find that the energy dissipation rate, the catalytic speed and the maximum adaptation accuracy in the I1-FFL network satisfy the same energy-speed-accuracy relationship as in the negative-feedback-loop (NFL) networks. Because the I1-FFL and NFL are the only two basic network motifs that enable accurate adaptation, our results suggest that a universal cost-performance trade-off principle may underlie all cellular adaptation processes independent of the detailed biochemical circuit architecture.

  12. Suggestions for planning a migration-monitoring network based on the experience of establishing and operating the maps program

    Science.gov (United States)

    David F. DeSante

    2005-01-01

    Based on the experience of creating and implementing the Monitoring Avian Productivity and Survivorship (MAPS) program, I suggest that, to be successful, a migration-monitoring network must: (1) provide strong justification for the data it proposes to collect; (2) provide direct links between those monitoring data and both research and management goals; (3) provide...

  13. The Experience of Introducing Secure E-Assessment in a South African University First-Year Foundational ICT Networking Course

    Science.gov (United States)

    Adesemowo, A. Kayode; Johannes, Hermien; Goldstone, Simon; Terblanche, Koshala

    2016-01-01

    This article illustrates the experience of introducing e-assessment to a foundational ICT networking course for a "large" group of first-year students at a South African Higher Education Institution. The study employed a mix of participatory action research, systems design, and survey (quantitative and qualitative) analysis over an…

  14. Social Networking and Social Support in Tourism Experience: The Moderating Role of Online Self-Presentation Strategies

    DEFF Research Database (Denmark)

    Kim, Jeongmi; Tussyadiah, Iis

    2013-01-01

    The purpose of this study is to provide an understanding of how tourists' self-presentation is managed on social networking sites (SNS). Specifically, the study investigated the effects of SNS use on social support and tourism experience and the moderating role of the different tourists' self-pre...

  15. The effects of individual- and network-level factors on discussion of cancer experiences: Survivors of childhood cancer in Korea.

    Science.gov (United States)

    Kim, Min Ah; Yi, Jaehee; Prince, Kort C; Nagelhout, Elizabeth; Wu, Yelena P

    2018-01-01

    This study aimed to identify young adult Korean cancer survivors' individual- (psychological distress, stigma, sociodemographic variables, and cancer-related variables) and network-level factors (relationship type, social support type) that influence discussion of their cancer experiences. Sixty-eight survivors of childhood cancer who were recruited using snowball sampling nominated 245 individuals from their networks, including family and intimate partners (40%) and friends and acquaintances (60%), as people with whom they most frequently interacted. Results of multilevel modeling analysis indicated that higher levels of internalized shame were a prominent individual-level factor associated with a lack of discussion of cancer experiences. Relationship type and support type at the network-level were also significant correlates of discussion of cancer experiences. Programs for reducing the survivors' shame, improving illness identity, and providing professional training for building social relationships that are intimate and in which they could exchange reciprocal support may help Korean childhood cancer survivors to openly share their cancer experiences with others in their social network and to be successful in the journey of cancer survivorship.

  16. Sensitive mother-to-adolescent disclosures after divorce: is the experience of sons different from that of daughters?

    Science.gov (United States)

    Koerner, Susan Silverberg; Wallace, Sara; Lehman, Stephanie Jacobs; Lee, Sun-A; Escalante, Kristine A

    2004-03-01

    This study addressed two main questions: (a) Are adolescent sons and daughters exposed to sensitive maternal disclosures after divorce with similar frequency and in similar detail? and (b) Does gender act as a moderator in the association between maternal disclosures and adolescent adjustment difficulties? Forced-choice and open-ended data were collected from 194 adolescents within 2 years after their parents' divorce. Quantitative analyses revealed that although the majority of adolescents experience some level of maternal disclosure, neither frequency nor detail of maternal disclosure differed as a function of adolescent gender. Frequent and detailed maternal disclosures were associated with adolescent adjustment difficulties, primarily psychological distress. Gender did not moderate that significant association. Qualitative analysis shed light on the link between maternal disclosures and adolescent distress, suggested the importance of how disclosures are made, and revealed several gender differences in reactions to maternal disclosures. Implications of the findings are discussed.

  17. Retrieval and molecule sensitivity studies for the global ozone monitoring experiment and the scanning imaging absorption spectrometer for atmospheric chartography

    Science.gov (United States)

    Chance, Kelly V.; Burrows, John P.; Schneider, Wolfgang

    1991-01-01

    The Global Ozone Monitoring Experiment (GOME) and the SCanning Imaging Absorption spectroMeter for Atmospheric CHartographY (SCIAMACHY) are diode based spectrometers that will make atmospheric constituent and aerosol measurements from European satellite platforms beginning in the mid 1990's. GOME measures the atmosphere in the UV and visible in nadir scanning, while SCIAMACHY performs a combination of nadir, limb, and occultation measurements in the UV, visible, and infrared. A summary is presented of the sensitivity studies that were performed for SCIAMACHY measurements. As the GOME measurement capability is a subset of the SCIAMACHY measurement capability, the nadir, UV, and visible portion of the studies is shown to apply to GOME as well.

  18. Sensitivity of the Humboldt Current system to global warming: a downscaling experiment of the IPSL-CM4 model

    Science.gov (United States)

    Echevin, Vincent; Goubanova, Katerina; Belmadani, Ali; Dewitte, Boris

    2012-02-01

    The impact of climate warming on the seasonal variability of the Humboldt Current system ocean dynamics is investigated. The IPSL-CM4 large scale ocean circulation resulting from two contrasted climate scenarios, the so-called Preindustrial and quadrupling CO2, are downscaled using an eddy-resolving regional ocean circulation model. The intense surface heating by the atmosphere in the quadrupling CO2 scenario leads to a strong increase of the surface density stratification, a thinner coastal jet, an enhanced Peru-Chile undercurrent, and an intensification of nearshore turbulence. Upwelling rates respond quasi-linearly to the change in wind stress associated with anthropogenic forcing, and show a moderate decrease in summer off Peru and a strong increase off Chile. Results from sensitivity experiments show that a 50% wind stress increase does not compensate for the surface warming resulting from heat flux forcing and that the associated mesoscale turbulence increase is a robust feature.

  19. 13C spin relaxation measurements in RNA: Sensitivity and resolution improvement using spin-state selective correlation experiments

    Energy Technology Data Exchange (ETDEWEB)

    Boisbouvier, Jerome; Brutscher, Bernhard; Simorre, Jean-Pierre; Marion, Dominique [C.N.R.S.-C.E.A., Institut de Biologie Structurale Jean-Pierre Ebel (France)

    1999-07-15

    A set of new NMR pulse sequences has been designed for the measurement of {sup 13}C relaxation rate constants in RNA and DNA bases: the spin-lattice relaxation rate constant R(C{sub z}), the spin-spin relaxation rate constant R(C{sub +}), and the CSA-dipolar cross-correlated relaxation rate constant {gamma}{sub C,CH}{sup xy}. The use of spin-state selective correlation techniques provides increased sensitivity and spectral resolution. Sensitivity optimised C-C filters are included in the pulse schemes for the suppression of signals originating from undesired carbon isotopomers. The experiments are applied to a 15% {sup 13}C-labelled 33-mer RNA-theophylline complex. The measured R(C{sub +})/{gamma}{sub C,CH}{sup xy} ratios indicate that {sup 13}C CSA tensors do not vary significantly for the same type of carbon (C{sub 2}, C{sub 6}, C{sub 8}), but that they differ from one type to another. In addition, conformational exchange effects in the RNA bases are detected as a change in the relaxation decay of the narrow {sup 13}C doublet component when varying the spacing of a CPMG pulse train. This new approach allows the detection of small exchange effects with a higher precision compared to conventional techniques.

  20. Phenomenology, genetics, and CNS network abnormalities in laryngeal dystonia: A 30-year experience.

    Science.gov (United States)

    Blitzer, Andrew; Brin, Mitchell F; Simonyan, Kristina; Ozelius, Laurie J; Frucht, Steven J

    2018-01-01

    Laryngeal dystonia (LD) is a functionally specific disorder of the afferent-efferent motor coordination system producing action-induced muscle contraction with a varied phenomenology. This report of long-term studies aims to review and better define the phenomenology and central nervous system abnormalities of this disorder and improve diagnosis and treatment. Our studies categorized over 1,400 patients diagnosed with LD over the past 33 years, including demographic and medical history records and their phenomenological presentations. Patients were grouped on clinical phenotype (adductor or abductor) and genotype (sporadic and familial) and with DNA analysis and functional magnetic resonance imaging (fMRI) to investigate brain organization differences and characterize neural markers for genotype/phenotype categorization. A number of patients with alcohol-sensitive dystonia were also studied. A spectrum of LD phenomena evolved: adductor, abductor, mixed, singer's, dystonic tremor, and adductor respiratory dystonia. Patients were genetically screened for DYT (dystonia) 1, DYT4, DYT6, and DYT25 (GNAL)-and several were positive. The functional MRI studies showed distinct alterations within the sensorimotor network, and the LD patients with a family history had distinct cortical and cerebellar abnormalities. A linear discriminant analysis of fMRI findings showed a 71% accuracy in characterizing LD from normal and in characterizing adductor from abductor forms. Continuous studies of LD patients over 30 years has led to an improved understanding of the phenomenological characteristics of this neurological disorder. Genetic and fMRI studies have better characterized the disorder and raise the possibility of making objective rather than subjective diagnoses, potentially leading to new therapeutic approaches. Laryngoscope, 128:S1-S9, 2018. © 2017 The American Laryngological, Rhinological and Otological Society, Inc.

  1. Art reaches within: aesthetic experience, the self and the default mode network

    Directory of Open Access Journals (Sweden)

    Edward A Vessel

    2013-12-01

    Full Text Available In a task of rating images of artworks in an fMRI scanner, regions in the medial prefrontal cortex that are known to be part of the default mode network (DMN were positively activated on the highest-rated trials. This is surprising given the DMN's original characterization as the set of brain regions that show greater fMRI activity during rest periods than during performance of tasks requiring focus on external stimuli. But further research showed that DMN regions could be positively activated also in structured tasks, if those tasks involved self-referential thought or self-relevant information. How may our findings be understood in this context? Although our task had no explicit self-referential aspect and the stimuli had no a priori self-relevance to the observers, the experimental design we employed emphasized the personal aspects of aesthetic experience. Observers were told that we were interested in their individual tastes, and asked to base their ratings on how much each artwork "moved" them. Moreover, we used little-known artworks that covered a wide range of styles, which led to high individual variability: each artwork was rated highly by some observers and poorly by others. This means that rating-specific neural responses cannot be attributed to the features of any particular artworks, but rather to the aesthetic experience itself. The DMN activity therefore suggests that certain artworks, albeit unfamiliar, may be so well-matched to an individual’s unique makeup that they obtain access to the neural substrates concerned with the self – access which other external stimuli normally do not get. This mediates a sense of being moved, or touched from within. This account is consistent with the modern notion that individuals’ taste in art is linked with their sense of identity, and suggests that DMN activity may serve to signal self-relevance in a broader sense than has been thought so far.

  2. Art reaches within: aesthetic experience, the self and the default mode network.

    Science.gov (United States)

    Vessel, Edward A; Starr, G Gabrielle; Rubin, Nava

    2013-12-30

    In a task of rating images of artworks in an fMRI scanner, regions in the medial prefrontal cortex that are known to be part of the default mode network (DMN) were positively activated on the highest-rated trials. This is surprising given the DMN's original characterization as the set of brain regions that show greater fMRI activity during rest periods than during performance of tasks requiring focus on external stimuli. But further research showed that DMN regions could be positively activated also in structured tasks, if those tasks involved self-referential thought or self-relevant information. How may our findings be understood in this context? Although our task had no explicit self-referential aspect and the stimuli had no a priori self-relevance to the observers, the experimental design we employed emphasized the personal aspects of aesthetic experience. Observers were told that we were interested in their individual tastes, and asked to base their ratings on how much each artwork "moved" them. Moreover, we used little-known artworks that covered a wide range of styles, which led to high individual variability: each artwork was rated highly by some observers and poorly by others. This means that rating-specific neural responses cannot be attributed to the features of any particular artworks, but rather to the aesthetic experience itself. The DMN activity therefore suggests that certain artworks, albeit unfamiliar, may be so well-matched to an individual's unique makeup that they obtain access to the neural substrates concerned with the self-access which other external stimuli normally do not get. This mediates a sense of being "moved," or "touched from within." This account is consistent with the modern notion that individuals' taste in art is linked with their sense of identity, and suggests that DMN activity may serve to signal "self-relevance" in a broader sense than has been thought so far.

  3. Upper mantle structure beneath the Hawaiian swell: Constraints from the ocean seismic network pilot experiment

    Science.gov (United States)

    Collins, J. A.; Vernon, F. L.; Orcutt, J. A.; Stephen, R. A.

    2002-06-01

    Data from two broadband, ocean-bottom seismographic stations deployed ~225 km southwest of Oahu, Hawaii during the Ocean Seismic Network Pilot Experiment provide constraints on upper mantle structure beneath the Hawaiian swell. Receiver functions show that the mantle transition zone is thinned by >50 km relative to reference model PA5, which, in the absence of compositional changes, implies excess temperatures of >350 K in the transition zone. The combination of the measurements reported here and the thickness variations reported by Li et al. [2000] imply that the transition zone is thinned by 30 +/- 15 km over an along-swell dimension of at least 700 km. At ~80 km depth, P-to-S converted phases are identified from the Gutenberg discontinuity marking the lid of the oceanic low-velocity zone and the base of the lithosphere. Shear-wave splitting measurements imply that fast-polarization azimuths are intermediate between the absolute plate-motion vector and the fossil spreading direction; multi-event stacked values of ø and δt are -80° and 1.5 s, respectively.

  4. Security of social network credentials for accessing course portal: Users' experience

    Science.gov (United States)

    Katuk, Norliza; Fong, Choo Sok; Chun, Koo Lee

    2015-12-01

    Social login (SL) has recently emerged as a solution for single sign-on (SSO) within the web and mobile environments. It allows users to use their existing social network credentials (SNC) to login to third party web applications without the need to create a new identity in the intended applications' database. Although it has been used by many web application providers, its' applicability in accessing learning materials is not yet fully investigated. Hence, this research aims to explore users' (i.e., instructors' and students') perception and experience on the security of SL for accessing learning contents. A course portal was developed for students at a higher learning institution and it provides two types of user authentications (i) traditional user authentication, and (ii) SL facility. Users comprised instructors and students evaluated the login facility of the course portal through a controlled lab experimental study following the within-subject design. The participants provided their feedback in terms of the security of SL for accessing learning contents. The study revealed that users preferred to use SL over the traditional authentication, however, they concerned on the security of SL and their privacy.

  5. The Midlatitude Continental Convective Clouds Experiment (MC3E) sounding network: operations, processing and analysis

    Science.gov (United States)

    Jensen, M. P.; Toto, T.; Troyan, D.; Ciesielski, P. E.; Holdridge, D.; Kyrouac, J.; Schatz, J.; Zhang, Y.; Xie, S.

    2015-01-01

    The Midlatitude Continental Convective Clouds Experiment (MC3E) took place during the spring of 2011 centered in north-central Oklahoma, USA. The main goal of this field campaign was to capture the dynamical and microphysical characteristics of precipitating convective systems in the US Central Plains. A major component of the campaign was a six-site radiosonde array designed to capture the large-scale variability of the atmospheric state with the intent of deriving model forcing data sets. Over the course of the 46-day MC3E campaign, a total of 1362 radiosondes were launched from the enhanced sonde network. This manuscript provides details on the instrumentation used as part of the sounding array, the data processing activities including quality checks and humidity bias corrections and an analysis of the impacts of bias correction and algorithm assumptions on the determination of convective levels and indices. It is found that corrections for known radiosonde humidity biases and assumptions regarding the characteristics of the surface convective parcel result in significant differences in the derived values of convective levels and indices in many soundings. In addition, the impact of including the humidity corrections and quality controls on the thermodynamic profiles that are used in the derivation of a large-scale model forcing data set are investigated. The results show a significant impact on the derived large-scale vertical velocity field illustrating the importance of addressing these humidity biases.

  6. An Experiment to Analyze Performance of Virtual Private Network Approach to Information Exchange between Health Facilities

    Directory of Open Access Journals (Sweden)

    Siphael BETUEL

    2017-06-01

    Full Text Available In developing countries, Tanzania in particular, studies and reports have depicted that there is a strong desire and need for seamless information exchange across health care providing facilities. A limited study conducted in few public and private hospitals has also revealed the same. On the other hand, the eHealth community has failed to effectively take advantage of the advances in technologies to make that desire come true. One potential technology is Virtual Private Network (VPN for which it has been noticed that there is a misconception and lack of innovative initiatives that slow down its uptake in eHealth. This article presents a technical assessment of the VPN technology in Tanzanian context. Primarily, the assessment focused on practicability of the best VPN practices and the perceived user experience performance when VPN is in use. It was observed that the response time dropped significantly as expected. The increase in response time and computer memory utilization is due to security mechanisms that are involved in VPN, the stronger security is used the more performance decreases. However, the increase in response time and computer memory utilization is very small in such a way that users will not be able to notice.

  7. Dynamics of the semantic priming shift: behavioral experiments and cortical network model.

    Science.gov (United States)

    Lavigne, Frédéric; Dumercy, Laurent; Chanquoy, Lucile; Mercier, Brunissende; Vitu-Thibault, Françoise

    2012-12-01

    Multiple semantic priming processes between several related and/or unrelated words are at work during the processing of sequences of words. Multiple priming generates rich dynamics of effects depending on the relationship between the target word and the first and/or second prime previously presented. The experimental literature suggests that during the on-line processing of the primes, the activation can shift from associates to the first prime to associates to the second prime. Though the semantic priming shift is central to the on-line and rapid updating of word meanings in the working memory, its precise dynamics are still poorly understood and it is still a challenge to model how it functions in the cerebral cortex. Four multiple priming experiments are proposed that cross-manipulate delays and association strength between the primes and the target. Results show for the first time that association strength determines complex dynamics of the semantic priming shift, ranging from an absence of a shift to a complete shift. A cortical network model of spike frequency adaptive neuron populations is proposed to account for the non-continuous evolution of the priming shift over time. It allows linking the dynamics of the priming shift assessed at the behavioral level to the non-linear dynamics of the firing rates of neurons populations.

  8. Exploring the functional brain network of Alzheimer's disease: based on the computational experiment.

    Directory of Open Access Journals (Sweden)

    YaPeng Li

    Full Text Available The purpose of this study is to explore the changes in functional brain networks of AD patients using complex network theory. In this study, resting-state fMRI datasets of 10 AD patients and 11 healthy controls were collected. Time series of 90 brain regions were extracted from the fMRI datasets after preprocessing. Pearson correlation method was used to calculate the correlation coefficient between any two time series. Then, a wide threshold range was selected to transform the adjacency matrix to a binary matrix under a different threshold. The topology parameters of each binary network were calculated, and all of them were then averaged within a group. During the evolution, node betweenness and the Euclidean distance between the nodes were set as control factors. Each binary network of healthy controls underwent evolution of 100 steps in accordance with the evolution rules. Then, the topology parameters of the evolution network were calculated. Finally, support vector machine (SVM was used to classify the network topology parameters of the evolution network and to determine whether evolution results matched the datasets from AD patients. We found there were differing degrees of decline in global efficiency, clustering coefficient, number of edges and transitivity in AD patients compared with healthy controls. The topology parameters of the evolution network tended toward those of the AD group. The results of SVM classification of the evolution network show that the evolution network had a greater probability to be classified as an AD patients group. A new biological marker for diagnosis of AD was provided through comparison of topology parameters between AD patients and healthy controls. The study of network evolution strategies enriched the method of brain network evolution. The use of SVM to classify the results of network evolution provides an objective criteria for determining evolution results.

  9. Properties of a pair of fracture networks produced by triaxial deformation experiments: insights on fluid flow using discrete fracture network models

    Science.gov (United States)

    Trullenque, Ghislain; Parashar, Rishi; Delcourt, Clément; Collet, Lucille; Villard, Pauline; Potel, Sébastien

    2017-05-01

    Results of a series of deformation experiments conducted on gabbro samples and numerical models for computation of flow are presented. Rocks were subjected to triaxial tests (σ1 > σ2 = σ3) under σ3 = 150 MPa confining pressure at room temperature, to generate fracture network patterns. These patterns were either produced by keeping a constant confining pressure and loading the sample up to failure (conventional test: CT), or by building up a high differential stress and suddenly releasing the confining pressure (confining pressure release test: CPR). The networks are similar in overall density but differ primarily in the orientation of smaller fractures. In the case of CT tests, a conjugate fracture set is observed with one dominant fracture zone running at about 20° from σ1. CPR tests do not show such a conjugate pattern and the mean fracture orientation is at around 35° from σ1. Discrete fracture network (DFN) methodology was used to determine the distribution of flow and hydraulic head for both fracture sets under simple boundary conditions and uniform transmissivity values. The fracture network generated by CT and CPR tests exhibit different patterns of flow field and hydraulic head configurations, but convey approximately the same amount of flow at all scales for which DFN models were simulated. The numerical modelling results help to develop understanding of qualitative differences in flow distribution that may arise in rocks of the same mineralogical composition and mechanical properties, but under the influence of different stress conditions, albeit at similar overall stress magnitude.

  10. Deep Sea Shell Taphonomy: Interactive benthic experiments in hydrate environments of Barkley Canyon, Ocean Networks Canada.

    Science.gov (United States)

    Best, Mairi; Purser, Autun

    2015-04-01

    In order to quantify and track the rates and processes of modification of biogenic carbonate in gas hydrate environments, and their possible environmental/ecological correlates, ongoing observations of experimentally deployed specimens are being made using a remotely controlled crawler with camera and sensors. The crawler is connected to NEPTUNE Canada, an 800km, 5-node, regional cabled ocean network across the northern Juan de Fuca Plate, northeastern Pacific, part of Ocean Networks Canada. One of 15 study areas is an environment of exposed hydrate mounds along the wall of Barkley Canyon, at ˜865m water depth. This is the home of a benthic crawler developed by Jacobs University of Germany, who is affectionately known as Wally. Wally is equipped with a range of sensors including cameras, methane sensor, current meter, fluorometer, turbidity meter, CTD, and a sediment microprofiler with probes for oxygen, methane, sulphide, pH, temperature, and conductivity. In conjunction with this sensor suite, a series of experiments have been designed to assess the cycling of biogenic carbon and carbonate in this complex environment. The biota range from microbes, to molluscs, to large fish, and therefore the carbon inputs include both a range of organic carbon compounds as well as the complex materials that are "biogenic carbonate". Controlled experimental specimens were deployed of biogenic carbonate (Mytilus edulis fresh shells) and cellulose (pieces of untreated pine lumber) that had been previously well characterized (photographed, weighed, and numbered, matching valves and lumber kept as controls). Deployment at the sediment/water interface was in such a way to maximize natural burial exhumation cycles but to minimize specimen interaction. 10 replicate specimens of each material were deployed in two treatments: 1) adjacent to a natural life and death assemblage of chemosynthetic bivalves and exposed hydrate on a hydrate mound and 2) on the muddy seafloor at a distance

  11. Adverse social experiences in adolescent rats result in enduring effects on social competence, pain sensitivity and endocannabinoid signaling

    Directory of Open Access Journals (Sweden)

    Peggy Schneider

    2016-10-01

    Full Text Available Social affiliation is essential for many species and gains significant importance during adolescence. Disturbances in social affiliation, in particular social rejection experiences during adolescence, affect an individual’s well-being and are involved in the emergence of psychiatric disorders. The underlying mechanisms are still unknown, partly because of a lack of valid animal models. By using a novel animal model for social peer-rejection, which compromises adolescent rats in their ability to appropriately engage in playful activities, here we report on persistent impairments in social behavior and dysregulations in the endocannabinoid system. From postnatal day (pd 21 to pd 50 adolescent female Wistar rats were either reared with same-strain partners (control or within a group of Fischer 344 rats (inadequate social rearing, ISR, previously shown to serve as inadequate play partners for the Wistar strain. Adult ISR animals showed pronounced deficits in social interaction, social memory, processing of socially transmitted information, and decreased pain sensitivity. Molecular analysis revealed increased CB1 receptor protein levels and CP55,940 stimulated 35SGTPγS binding activity specifically in the amygdala and thalamus in previously peer-rejected rats. Along with these changes, increased levels of the endocannabinoid anandamide and a corresponding decrease of its degrading enzyme fatty acid amide hydrolase were seen in the amygdala. Our data indicate lasting consequences in social behavior and pain sensitivity following peer-rejection in adolescent female rats. These behavioral impairments are accompanied by persistent alterations in CB1 receptor signaling. Finally, we provide a novel translational approach to characterize neurobiological processes underlying social peer-rejection in adolescence.

  12. Experiences, challenges and lessons from rolling out a rural WiFi mesh network

    CSIR Research Space (South Africa)

    Rey-Moreno, C

    2013-01-01

    Full Text Available rural communities worldwide. This paper argues that the latest wave of WiFi mesh networks offers benefits that traditional top-down WiFi and mobile networks do not. In addition, we propose ethnographic and participatory methods to aid the effective...

  13. The Impact of Network Relationships, Prison Experiences, and Internal Transformation on Women's Success after Prison Release

    Science.gov (United States)

    Bui, Hoan N.; Morash, Merry

    2010-01-01

    Using data obtained from retrospective, in-depth interviews with 20 successful female parolees, the present study examines the effects of women offenders' relationships with people in their social networks (i.e., their network relationships) before, during, and after incarceration on their postrelease desistence from crime. Because women's social…

  14. Using a Classification of Psychological Experience in Social-Networking Sites as a Virtual Learning Environment

    Science.gov (United States)

    Onibokun, Joseph; van Schaik, Paul

    2012-01-01

    With over 800 million users worldwide, the global importance of Facebook as a social-networking platform is beyond doubt. This popularity, particularly among university-students, has encouraged research to explore ways in which social networking can be adapted into virtual learning environments. In particular, this study uses the think-aloud…

  15. Networking for Innovation in South Wales. Experiences in Developing Productive Links between University and Industry.

    Science.gov (United States)

    Jones, Haydn; Jenkins, Sarah

    1999-01-01

    To develop productive links between industry and university, the style and ethos of networks focused on innovation are crucial. Cardiff University (Wales) has an innovation network that stimulates collaborative work and technology transfer through its informal open nature that encourages partnership. (SK)

  16. Developing Preceptors through Virtual Communities and Networks: Experiences from a Pilot Project.

    Science.gov (United States)

    Ackman, Margaret L; Romanick, Marcel

    2011-11-01

    Supporting preceptors is critical to the expansion of experiential learning opportunities for the pharmacy profession. Informal learning opportunities within communities of practitioners are important for hospital preceptors. However, such communities may be limited by geographic separation of preceptors from peers, faculty members, and supports within the pharmacy services department. To use computer-mediated conferencing to create a sense of community among preceptors, specifically by using this medium to provide initial development of and continuing support for preceptors, and to examine preceptors' satisfaction with this approach. Thirty-nine preceptors who had completed a day-long face-to-face preceptor development workshop and who were supervising students in 1 of 2 specific rotation blocks were invited to participate in the study. The pharmacists used computer-mediated conferencing to meet for virtual networking about specific topics. They met once before the student rotation to receive instructions about the technology and to discuss student orientation and scheduling, and 3 times during the student rotation for open discussion of specific topics. Evaluation and feedback were solicited by means of an electronic survey and virtual (i.e., computer-based) feedback sessions with an independent facilitator. The response rate was 66% (26/39) for the electronic survey, but only 15% (6/39) for the virtual feedback sessions. All of the respondents were experienced preceptors, but for 92% (22/24), this was their first experience with computer-mediated conferencing. Overall, the sessions had a positive reception, and participants found it useful to share information and experiences with other preceptors. The main challenges were related to the technology, perceived lack of support for their participation in the sessions, and inconvenience related to the timing of sessions. Computer-mediated conferencing allowed preceptors to learn from and to support each other

  17. Full Scale Earth Fault Experiments on 10 kV laboratory network with comparative Measurements on Conventional CT's and VT's

    DEFF Research Database (Denmark)

    Sørensen, Stefan; Nielsen, Hans Ove; Bak-Jensen, Birgitte

    2002-01-01

    transformers (CT?s) and voltage transformers (VT?s) by an optical link. Comparison with a similar earlier performed experiment caried out autumn 1998, where current and voltage measurements were measured with high bandwidth Rugowski-coils and high voltage Tektronix probes, gave remarkable results......In this paper we present a result of a full scale earth fault carried out on the 10 kV research/laboratory distribution network at Kyndbyvaerket Denmark in May 2001. The network is compensated through a Petersen-Coil and current and voltage measurements were measured on conventional current....... The necessity of high bandwidth measurement equipment for earth fault measurements on compensated distribution networks can be undermined, since it will be shown that the transient signal transfer through conventional CT?s and VT?s for further signal analysis is sufficient. Caused the inadequacy three phase...

  18. Leuconostoc Mesenteroides Growth in Food Products: Prediction and Sensitivity Analysis by Adaptive-Network-Based Fuzzy Inference Systems

    OpenAIRE

    Wang, Hue-Yu; Wen, Ching-Feng; Chiu, Yu-Hsien; Lee, I-Nong; Kao, Hao-Yun; Lee, I-Chen; Ho, Wen-Hsien

    2013-01-01

    BACKGROUND: An adaptive-network-based fuzzy inference system (ANFIS) was compared with an artificial neural network (ANN) in terms of accuracy in predicting the combined effects of temperature (10.5 to 24.5°C), pH level (5.5 to 7.5), sodium chloride level (0.25% to 6.25%) and sodium nitrite level (0 to 200 ppm) on the growth rate of Leuconostoc mesenteroides under aerobic and anaerobic conditions. METHODS: THE ANFIS AND ANN MODELS WERE COMPARED IN TERMS OF SIX STATISTICAL INDICES CALCULATED B...

  19. Greenhouse gas network design using backward Lagrangian particle dispersion modelling – Part 2: Sensitivity analyses and South African test case

    CSIR Research Space (South Africa)

    Nickless, A

    2014-05-01

    Full Text Available Greenhouse gase network design South Africa A. Nickless et al. Title Page Abstract Introduction Conclusions References Tables Figures J I J I Back Close Full Screen / Esc Printer-friendly Version Interactive Discussion D iscussion P aper | D iscussion P aper... and Physics O pen Access Discussions This discussion paper is/has been under review for the journal Atmospheric Chemistry and Physics (ACP). Please refer to the corresponding final paper in ACP if available. Greenhouse gas network design using backward...

  20. Experiences with using information and communication technology to build a multi-municipal support network for informal carers.

    Science.gov (United States)

    Torp, Steffen; Bing-Jonsson, Pia C; Hanson, Elizabeth

    2013-09-01

    This multi-municipal intervention study explored whether informal carers of frail older people and disabled children living at home made use of information and communication technology (ICT) to gain knowledge about caring and to form informal support networks, thereby improving their health. Seventy-nine informal carers accessed web-based information about caring and an e-based discussion forum via their personal computers. They were able to maintain contact with each other using a web camera and via normal group meetings. After the first 12 months, 17 informal carers participated in focus group interviews and completed a short questionnaire. Four staff members were also interviewed. Participant carers who had prior experiences with a similar ICT-based support network reported greater satisfaction and more extensive use of the network than did participants with no such prior experience. It seems that infrequent usage of the service may be explained by too few other carers to identify with and inappropriate recruitment procedures. Nevertheless, carers of disabled children reported that the intervention had resulted in improved services across the participant municipalities. To achieve optimal effects of an ICT-based support network due attention must be given to recruitment processes and social environment building for which care practitioners require training and support.

  1. Experiments in Neural-Network Control of a Free-Flying Space Robot

    Science.gov (United States)

    Wilson, Edward

    1995-01-01

    Four important generic issues are identified and addressed in some depth in this thesis as part of the development of an adaptive neural network based control system for an experimental free flying space robot prototype. The first issue concerns the importance of true system level design of the control system. A new hybrid strategy is developed here, in depth, for the beneficial integration of neural networks into the total control system. A second important issue in neural network control concerns incorporating a priori knowledge into the neural network. In many applications, it is possible to get a reasonably accurate controller using conventional means. If this prior information is used purposefully to provide a starting point for the optimizing capabilities of the neural network, it can provide much faster initial learning. In a step towards addressing this issue, a new generic Fully Connected Architecture (FCA) is developed for use with backpropagation. A third issue is that neural networks are commonly trained using a gradient based optimization method such as backpropagation; but many real world systems have Discrete Valued Functions (DVFs) that do not permit gradient based optimization. One example is the on-off thrusters that are common on spacecraft. A new technique is developed here that now extends backpropagation learning for use with DVFs. The fourth issue is that the speed of adaptation is often a limiting factor in the implementation of a neural network control system. This issue has been strongly resolved in the research by drawing on the above new contributions.

  2. Sensitivity of the Gravity Recovery and Climate Experiment (GRACE) to the complexity of aquifer systems for monitoring of groundwater

    Science.gov (United States)

    Katpatal, Yashwant B.; Rishma, C.; Singh, Chandan K.

    2017-11-01

    The Gravity Recovery and Climate Experiment (GRACE) satellite mission is aimed at assessment of groundwater storage under different terrestrial conditions. The main objective of the presented study is to highlight the significance of aquifer complexity to improve the performance of GRACE in monitoring groundwater. Vidarbha region of Maharashtra, central India, was selected as the study area for analysis, since the region comprises a simple aquifer system in the western region and a complex aquifer system in the eastern region. Groundwater-level-trend analyses of the different aquifer systems and spatial and temporal variation of the terrestrial water storage anomaly were studied to understand the groundwater scenario. GRACE and its field application involve selecting four pixels from the GRACE output with different aquifer systems, where each GRACE pixel encompasses 50-90 monitoring wells. Groundwater storage anomalies (GWSA) are derived for each pixel for the period 2002 to 2015 using the Release 05 (RL05) monthly GRACE gravity models and the Global Land Data Assimilation System (GLDAS) land-surface models (GWSAGRACE) as well as the actual field data (GWSAActual). Correlation analysis between GWSAGRACE and GWSAActual was performed using linear regression. The Pearson and Spearman methods show that the performance of GRACE is good in the region with simple aquifers; however, performance is poorer in the region with multiple aquifer systems. The study highlights the importance of incorporating the sensitivity of GRACE in estimation of groundwater storage in complex aquifer systems in future studies.

  3. Experience of using an interdisciplinary task force to develop a culturally sensitive multipronged tool to improve stroke outcomes in Nigeria

    Directory of Open Access Journals (Sweden)

    Oyedunni S. Arulogun

    2016-09-01

    Full Text Available The burden of stroke is on the rise in Nigeria. A multi-faceted strategy is essential for reducing this growing burden and includes promoting medication adherence, optimizing traditional biomarker risk targets (blood pressure, cholesterol and encouraging beneficial lifestyle practices. Successful implementation of this strategy is challenged by inadequate patient health literacy, limited patient/medical system resources, and lack of a coordinated interdisciplinary treatment approach. Moreover, the few interventions developed to improve medical care in Nigeria have generally been aimed at physicians (primarily and nurses (secondarily with minimal input from other key health care providers, and limited contributions from patients, caregivers, and the community itself. The Tailored Hospital-based Risk Reduction to Impede Vascular Events after Stroke (THRIVES study is assessing the efficacy of a culturally sensitive multidimensional intervention for controlling blood pressure in recent stroke survivors. A key component of the intervention development process was the constitution of a project task force comprising various healthcare providers and administrators. This paper describes the unique experience in Sub-Saharan Africa of utilizing of an interdisciplinary Task force to facilitate the development of the multipronged behavioral intervention aimed at enhancing stroke outcomes in a low-middle income country.

  4. High-sensitivity and specificity of laser-induced autofluorescence spectra for detection of colorectal cancer with an artificial neural network

    Science.gov (United States)

    Kwek, L. C.; Fu, Sheng; Chia, T. C.; Diong, C. H.; Tang, C. L.; Krishnan, S. M.

    2005-07-01

    An artificial neural network (ANN) has been used in various clinical research for the prediction and classification of data in cancer disease. Previous research in this direction focused on the correlation between various input parameters such as age, antigen, and size of tumor growth. Recently, laser-induced autofluorescence (LIAF) techniques have been shown to be a useful noninvasive early diagnostic tool for various cancer diseases. We report on a successful application of ANN to in vitro LIAF spectra. We show that classification of tumor samples with ANN can be done with high sensitivity, specificity, and accuracy. Thus a combination of LIAF techniques and ANN can provide a robust method for clinical diagnosis.

  5. The photoelectric effect and study of the diffraction of light: Two new experiments in UNILabs virtual and remote laboratories network

    Science.gov (United States)

    Pedro Sánchez, Juan; Sáenz, Jacobo; de la Torre, Luis; Carreras, Carmen; Yuste, Manuel; Heradio, Rubén; Dormido, Sebastián

    2016-05-01

    This work describes two experiments: "study of the diffraction of light: Fraunhofer approximation" and "the photoelectric effect". Both of them count with a virtual, simulated, version of the experiment as well as with a real one which can be operated remotely. The two previous virtual and remote labs (built using Easy Java(script) Simulations) are integrated in UNILabs, a network of online interactive laboratories based on the free Learning Management System Moodle. In this web environment, students can find not only the virtual and remote labs but also manuals with related theory, the user interface description for each application, and so on.

  6. Experience of wireless local area network in a radiation oncology department.

    Science.gov (United States)

    Mandal, Abhijit; Asthana, Anupam Kumar; Aggarwal, Lalit Mohan

    2010-01-01

    The aim of this work is to develop a wireless local area network (LAN) between different types of users (Radiation Oncologists, Radiological Physicists, Radiation Technologists, etc) for efficient patient data management and to made easy the availability of information (chair side) to improve the quality of patient care in Radiation Oncology department. We have used mobile workstations (Laptops) and stationary workstations, all equipped with wireless-fidelity (Wi-Fi) access. Wireless standard 802.11g (as recommended by Institute of Electrical and Electronic Engineers (IEEE, Piscataway, NJ) has been used. The wireless networking was configured with the Service Set Identifier (SSID), Media Access Control (MAC) address filtering, and Wired Equivalent Privacy (WEP) network securities. We are successfully using this wireless network in sharing the indigenously developed patient information management software. The proper selection of the hardware and the software combined with a secure wireless LAN setup will lead to a more efficient and productive radiation oncology department.

  7. Experience of wireless local area network in a radiation oncology department

    Directory of Open Access Journals (Sweden)

    Mandal Abhijit

    2010-01-01

    Full Text Available The aim of this work is to develop a wireless local area network (LAN between different types of users (Radiation Oncologists, Radiological Physicists, Radiation Technologists, etc for efficient patient data management and to made easy the availability of information (chair side to improve the quality of patient care in Radiation Oncology department. We have used mobile workstations (Laptops and stationary workstations, all equipped with wireless-fidelity (Wi-Fi access. Wireless standard 802.11g (as recommended by Institute of Electrical and Electronic Engineers (IEEE, Piscataway, NJ has been used. The wireless networking was configured with the Service Set Identifier (SSID, Media Access Control (MAC address filtering, and Wired Equivalent Privacy (WEP network securities. We are successfully using this wireless network in sharing the indigenously developed patient information management software. The proper selection of the hardware and the software combined with a secure wireless LAN setup will lead to a more efficient and productive radiation oncology department.

  8. A Limited Objective Experiment on Wireless Peer-To-Peer Collaborative Networking

    National Research Council Canada - National Science Library

    Bordetsky, Alex; Cook, Glenn R; Kemple, Bill; Thate, Timothy

    2002-01-01

    ... with client-server applications. The authors discuss the wireless network operation challenges leading to the solutions for scaling up application-sharing and improving collaborators' self-organizing behavior.

  9. Innovation in Innovation Management: The Experience of Petrobras Centers and Networks of Excellence Program

    Directory of Open Access Journals (Sweden)

    Ana Maria de Britto Pires

    2013-04-01

    Full Text Available Since 1996, Petrobras – Petróleo Brasileiro S.A., the biggest company in Latin America, has supported the development of a method to structure networks of partnerships called Centers and Networks of Excellence Practice (PCREX. It aims to support the establishment of centers and networks of excellence in areas in which innovation depends heavily on the articulation of various players from outside the company and different internal areas. This article presents the results of the analysis of the PCREX method, including its characterization and field research carried out in eight Centers and Networks of Excellence developed by Petrobras. The field research and subsequent analysis helped identify (i the alignment between the PCREX method and the best innovation management practices and (ii the difficulties faced by new management models based on resource and knowledge sharing, which highlights that organizational innovations need to be able to count on strong institutional support to succeed.

  10. Information Assurance in Networked Enterprises: MICSS Class Experiments and Industry Survey Analysis

    National Research Council Canada - National Science Library

    Ray, Parbati

    2001-01-01

    .... The surveys give an insight into how inter-networked companies use their ERP systems, whet their current policies maybe with respect to information management, and what their security and assurance problems maybe...

  11. Assessment of the Worldwide Antimalarial Resistance Network Standardized Procedure for In Vitro Malaria Drug Sensitivity Testing Using SYBR Green Assay for Field Samples with Various Initial Parasitemia Levels.

    Science.gov (United States)

    Cheruiyot, Agnes C; Auschwitz, Jennifer M; Lee, Patricia J; Yeda, Redemptah A; Okello, Charles O; Leed, Susan E; Talwar, Mayank; Murthy, Tushar; Gaona, Heather W; Hickman, Mark R; Akala, Hoseah M; Kamau, Edwin; Johnson, Jacob D

    2016-04-01

    The malaria SYBR green assay, which is used to profilein vitrodrug susceptibility ofPlasmodium falciparum, is a reliable drug screening and surveillance tool. Malaria field surveillance efforts provide isolates with various low levels of parasitemia. To be advantageous, malaria drug sensitivity assays should perform reproducibly among various starting parasitemia levels rather than at one fixed initial value. We examined the SYBR green assay standardized procedure developed by the Worldwide Antimalarial Resistance Network (WWARN) for its sensitivity and ability to accurately determine the drug concentration that inhibits parasite growth by 50% (IC50) in samples with a range of initial parasitemia levels. The initial sensitivity determination of the WWARN procedure yielded a detection limit of 0.019% parasitemia.P. falciparumlaboratory strains and field isolates with various levels of initial parasitemia were then subjected to a range of doses of common antimalarials. The IC50s were comparable for laboratory strains with between 0.0375% and 0.6% parasitemia and for field isolates with between 0.075% and 0.6% parasitemia for all drugs tested. Furthermore, assay quality (Z') analysis indicated that the WWARN procedure displays high robustness, allowing for drug testing of malaria field samples within the derived range of initial parasitemia. The use of the WWARN procedure should allow for the inclusion of more malaria field samples in malaria drug sensitivity screens that would have otherwise been excluded due to low initial parasitemia levels. Copyright © 2016, American Society for Microbiology. All Rights Reserved.

  12. Childhood trauma as a risk factor for the onset of subclinical psychotic experiences: Exploring the mediating effect of stress sensitivity in a cross-sectional epidemiological community study.

    Science.gov (United States)

    Rössler, Wulf; Ajdacic-Gross, Vladeta; Rodgers, Stephanie; Haker, Helene; Müller, Mario

    2016-04-01

    Childhood trauma is a risk factor for the onset of schizophrenic psychosis. Because the psychosis phenotype can be described as a continuum with varying levels of severity and persistence, childhood trauma might likewise increase the risk for psychotic experiences below the diagnostic threshold. But the impact of stressful experiences depends upon its subjective appraisal. Therefore, varying degrees of stress sensitivity possibly mediate how childhood trauma impacts in the end upon the occurrence of subclinical psychotic experiences. We investigated this research question in a representative community cohort of 1500 participants. A questionnaire, comprising five domains of physical and emotional neglect, as well as physical, emotional, and sexual abuse, was used to assess childhood trauma. Based on different symptoms of subclinical psychotic experiences, we conducted a latent profile analysis (LPA) to derive distinct profiles for such experiences. Path modeling was performed to identify the direct and indirect (via stress sensitivity) pathways from childhood trauma to subclinical psychotic experiences. The LPA revealed four classes - unaffected, anomalous perceptions, odd beliefs and behavior, and combined anomalous perceptions/odd beliefs and behavior, that - except for sexual abuse - were all linked to childhood trauma. Moreover, except for physical abuse, childhood trauma was significantly associated with stress sensitivity. Thus, our results revealed that the pathways from emotional neglect/abuse and physical neglect to subclinical psychotic experiences were mediated by stress sensitivity. In conclusion, we can state that subclinical psychotic experiences are affected by childhood traumatic experiences in particular through the pathway of a heightened subjective stress appraisal. Copyright © 2016 Elsevier B.V. All rights reserved.

  13. Full Service ISDN Satellite (FSIS) network model for advanced ISDN satellite design and experiments

    Science.gov (United States)

    Pepin, Gerard R.

    1992-01-01

    The Full Service Integrated Services Digital Network (FSIS) network model for advanced satellite designs describes a model suitable for discrete event simulations. A top down model design uses the Advanced Communications Technology Satellite (ACTS) as its basis. The ACTS and the Interim Service ISDN Satellite (ISIS) perform ISDN protocol analyses and switching decisions in the terrestrial domain, whereas FSIS makes all its analyses and decisions on-board the ISDN satellite.

  14. Research network on capital markets and financial integration in Europe : results and experience after two years

    OpenAIRE

    European Central Bank ; Center for Financial Studies (CFS)

    2008-01-01

    In April 2002 the European Central Bank (ECB) and the Center for Financial Studies (CFS) launched the ECB-CFS Research Network to promote research on “Capital Markets and Financial Integration in Europe”. The ECB-CFS research network aims at stimulating top-level and policy-relevant research, significantly contributing to the understanding of the current and future structure and integration of the financial system in Europe and its international linkages with the United States and Japan. This...

  15. Stress dependent fluid flow in porous rock: experiments and network modelling

    Energy Technology Data Exchange (ETDEWEB)

    Flornes, Olav

    2005-07-01

    permeability change was the same in the two directions. When a rock is subjected to sufficiently high stresses, permanent damage, or failure, occurs and we expect a more drastic change in its properties. In a series of experiments on three different materials, we study how permeability is changed by different failure modes. We observed that permeability followed the volumetric strain independent of failure mode in two of the materials, Saltwash and Tuffeau de Maastricht, while for Red Wildmoor, the permeability changed in a more complex manner. We present two numerical models that study how deformation and fluid flow are related. While they are both network models, one is focused on the effect of changed porosity on permeability, and tries to give some insight to the experimental results described above. The other one is more theoretical, and investigates some universal properties associated with hydraulic fracturing using a Biot-Cosserat model (author) (ml)

  16. Responsive and resilient supply chain network design under operational and disruption risks with delivery lead-time sensitive customers

    DEFF Research Database (Denmark)

    Fattahi, Mohammad; Govindan, Kannan; Keyvanshokooh, Esmaeil

    2017-01-01

    a multi-stage stochastic program, and model disruptions’ effect on facilities’ capacity. The SC responsiveness risk is limited and, to obtain a resilient network, both mitigation and contingency strategies are exploited. Computational results on a real-life case study and randomly generated problem...... instances demonstrate the model's applicability, risk-measurement policies’ performance, and the influence of mitigation and contingency strategies on SC's resiliency....

  17. Standard skin prick testing and sensitization to inhalant allergens across Europe--a survey from the GALEN network

    NARCIS (Netherlands)

    Heinzerling, L.; Frew, A. J.; Bindslev-Jensen, C.; Bonini, S.; Bousquet, J.; Bresciani, M.; Carlsen, K.-H.; van Cauwenberge, P.; Darsow, U.; Fokkens, W. J.; Haahtela, T.; van Hoecke, H.; Jessberger, B.; Kowalski, M. L.; Kopp, T.; Lahoz, C. N.; Lodrup Carlsen, K. C.; Papadopoulos, N. G.; Ring, J.; Schmid-Grendelmeier, P.; Vignola, A. M.; Wöhrl, S.; Zuberbier, T.

    2005-01-01

    Skin prick testing (SPT) is the standard method for diagnosing allergic sensitization but is to some extent performed differently in clinical centres across Europe. There would be advantages in harmonizing the standard panels of allergens used in different European countries, both for clinical

  18. The North East Italy (NI) broadband seismic network run by OGS: experience in improving the long period performances

    Science.gov (United States)

    Pesaresi, D.

    2009-04-01

    experimented and routinely used by the world wide GEOFON seismic network and the German regional seismic network: examples and performances of a typical OGS installation will be shown.

  19. Percolated pore networks of oxygen plasma-activated multi-walled carbon nanotubes for fast response, high sensitivity capacitive humidity sensors

    Science.gov (United States)

    Hong, H. P.; Jung, K. H.; Kim, J. H.; Kwon, K. H.; Lee, C. J.; Yun, K. N.; Min, N. K.

    2013-03-01

    We report on the preparation of capacitive-type relative humidity sensors incorporating plasma-activated multi-wall carbon nanotube (p-MWCNT) electrodes and on their performance compared with existing commercial technology. Highly open porous conductive electrodes, which are almost impossible to obtain with conventional metal electrodes, are fabricated by spray-depositing MWCNT networks on a polyimide layer. Oxygen plasma activation of the MWCNTs is also explored to improve the water adsorption of the MWCNT films, by introducing oxygen-containing functional groups on the CNT surface. Polyimide humidity sensors with optimized p-MWCNT network electrodes exhibit exceptionally fast response times (1.5 for adsorption and 2 s for desorption) and high sensitivity (0.75 pF/% RH). These results may be partially due to their percolated pore structure being more accessible for water molecules, expending the diffusion of moisture to the polyimide sensing film, and partially due to the oxygenated surface of p-MWCNT films, allocating more locations for adsorption or attraction of water molecules to contribute to the sensitivity.

  20. Application of a design of experiment approach in the development of a sensitive bioanalytical assay in human plasma.

    Science.gov (United States)

    Dawes, Michelle L; Bergum, James S; Schuster, Alan E; Aubry, Anne-Françoise

    2012-11-01

    To support a first-in-human (FIH) clinical study in healthy volunteers, a human plasma assay, a 20-fold more sensitive method than the validated non-clinical LC-MS/MS assays, was requested. For the clinical assay, a LLOQ of 0.050 ng/mL for Compound A and 0.100 ng/mL for Compound B was desired to accurately determine the analyte concentrations in human plasma samples across all treatment groups. A design of experiment (DOE) investigation was performed in an effort to optimize the extraction procedure of the bioanalytical assay used to support the first in human study and future clinical studies. Three factors, extraction buffer pH (two pHs), volume ratio of organic solvent to plasma (two ratios), and extraction shake time (three times), were selected for the DOE. Both analytes were analyzed at a low concentration, 0.150 ng/mL, and a stable isotope label internal standard was used for each analyte. To estimate the recovery of each analyte from the extraction, the response ratio of each analyte over the respective internal standard was used, and to estimate matrix effects, the absolute response (peak area) of each analyte was used. The results of the DOE indicated that the three factors tested had a more significant effect on the extraction of the metabolite, Compound B, compared to that of the parent, Compound A. The extraction buffer pH had the greatest influence on Compound B and the volume of extraction solvent had an influence on both analytes. Unexpectedly, a longer extraction time caused an apparent decrease in the overall recovery for both analytes. This was presumably due to an increased extraction of interfering matrix components. Optimal conditions were achieved for the combined analysis of both compounds using the DOE approach. Copyright © 2012 Elsevier B.V. All rights reserved.

  1. Linking experiment and theory for three-dimensional networked binary metal nanoparticle–triblock terpolymer superstructures

    KAUST Repository

    Li, Zihui

    2014-02-21

    © 2014 Macmillan Publishers Limited. Controlling superstructure of binary nanoparticle mixtures in three dimensions from self-assembly opens enormous opportunities for the design of materials with unique properties. Here we report on how the intimate coupling of synthesis, in-depth electron tomographic characterization and theory enables exquisite control of superstructure in highly ordered porous three-dimensional continuous networks from single and binary mixtures of metal nanoparticles with a triblock terpolymer. Poly(isoprene-block-styrene-block-(N,N-dimethylamino)ethyl methacrylate) is synthesized and used as structure-directing agent for ligand-stabilized platinum and gold nanoparticles. Quantitative analysis provides insights into short-and long-range nanoparticle-nanoparticle correlations, and local and global contributions to structural chirality in the networks. Results provide synthesis criteria for next-generation mesoporous network superstructures from binary nanoparticle mixtures for potential applications in areas including catalysis.

  2. Experience in Strategic Networking to Promote Palliative Care in a Clinical Academic Setting in India

    Science.gov (United States)

    Nair, Shoba; Tarey, SD; Barathi, B; Mary, Thiophin Regina; Mathew, Lovely; Daniel, Sudha Pauline

    2016-01-01

    Background: Palliative care in low and middle-income countries is a new discipline, responding to a greater patient need, than in high-income countries. By its very nature, palliative as a specialty has to network with other specialties to provide quality care to patients. For any medical discipline to grow as a specialty, it should be well established in the teaching medical institutions of that country. Data show that palliative care is more likely to establish and grow in an academic health care institution. It is a necessity that multiple networking strategies are adopted to reach this goal. Objectives: (1) To describe a strategic approach to palliative care service development and integration into clinical academic setting. (2) To present the change in metrics to evaluate progress. Design and Setting: This is a descriptive study wherein, the different strategies that are adopted by the Department of Palliative Medicine for networking in an academic health care institution and outside the institution are scrutinized. Measurement: The impact of this networking was assessed, one, at the level of academics and the other, at the level of service. The number of people who attended various training programs conducted by the department and the number of patients who availed palliative care service over the years were assessed. Results: Ten different strategies were identified that helped with networking of palliative care in the institution. During this time, the referrals to the department increased both for malignant diseases (52–395) and nonmalignant diseases (5–353) from 2000 to 2013. The academic sessions conducted by the department for undergraduates also saw an increase in the number of hours from 6 to 12, apart from the increase in a number of courses conducted by the department for doctors and nurses. Conclusion: Networking is an essential strategy for the establishment of a relatively new medical discipline like palliative care in a developing and

  3. Experience in Strategic Networking to Promote Palliative Care in a Clinical Academic Setting in India.

    Science.gov (United States)

    Nair, Shoba; Tarey, S D; Barathi, B; Mary, Thiophin Regina; Mathew, Lovely; Daniel, Sudha Pauline

    2016-01-01

    Palliative care in low and middle-income countries is a new discipline, responding to a greater patient need, than in high-income countries. By its very nature, palliative as a specialty has to network with other specialties to provide quality care to patients. For any medical discipline to grow as a specialty, it should be well established in the teaching medical institutions of that country. Data show that palliative care is more likely to establish and grow in an academic health care institution. It is a necessity that multiple networking strategies are adopted to reach this goal. (1) To describe a strategic approach to palliative care service development and integration into clinical academic setting. (2) To present the change in metrics to evaluate progress. This is a descriptive study wherein, the different strategies that are adopted by the Department of Palliative Medicine for networking in an academic health care institution and outside the institution are scrutinized. The impact of this networking was assessed, one, at the level of academics and the other, at the level of service. The number of people who attended various training programs conducted by the department and the number of patients who availed palliative care service over the years were assessed. Ten different strategies were identified that helped with networking of palliative care in the institution. During this time, the referrals to the department increased both for malignant diseases (52-395) and nonmalignant diseases (5-353) from 2000 to 2013. The academic sessions conducted by the department for undergraduates also saw an increase in the number of hours from 6 to 12, apart from the increase in a number of courses conducted by the department for doctors and nurses. Networking is an essential strategy for the establishment of a relatively new medical discipline like palliative care in a developing and populous country like India, where the service is disproportionate to the demands.

  4. Simulating microinjection experiments in a novel model of the rat sleep-wake regulatory network.

    Science.gov (United States)

    Diniz Behn, Cecilia G; Booth, Victoria

    2010-04-01

    This study presents a novel mathematical modeling framework that is uniquely suited to investigating the structure and dynamics of the sleep-wake regulatory network in the brain stem and hypothalamus. It is based on a population firing rate model formalism that is modified to explicitly include concentration levels of neurotransmitters released to postsynaptic populations. Using this framework, interactions among primary brain stem and hypothalamic neuronal nuclei involved in rat sleep-wake regulation are modeled. The model network captures realistic rat polyphasic sleep-wake behavior consisting of wake, rapid eye movement (REM) sleep, and non-REM (NREM) sleep states. Network dynamics include a cyclic pattern of NREM sleep, REM sleep, and wake states that is disrupted by simulated variability of neurotransmitter release and external noise to the network. Explicit modeling of neurotransmitter concentrations allows for simulations of microinjections of neurotransmitter agonists and antagonists into a key wake-promoting population, the locus coeruleus (LC). Effects of these simulated microinjections on sleep-wake states are tracked and compared with experimental observations. Agonist/antagonist pairs, which are presumed to have opposing effects on LC activity, do not generally induce opposing effects on sleep-wake patterning because of multiple mechanisms for LC activation in the network. Also, different agents, which are presumed to have parallel effects on LC activity, do not induce parallel effects on sleep-wake patterning because of differences in the state dependence or independence of agonist and antagonist action. These simulation results highlight the utility of formal mathematical modeling for constraining conceptual models of the sleep-wake regulatory network.

  5. Assessing the user experience of older adults using a neural network trained to recognize emotions from brain signals.

    Science.gov (United States)

    Meza-Kubo, Victoria; Morán, Alberto L; Carrillo, Ivan; Galindo, Gilberto; García-Canseco, Eloisa

    2016-08-01

    The use of Ambient Assisted Living (AAL) technologies as a means to cope with problems that arise due to an increasing and aging population is becoming usual. AAL technologies are used to prevent, cure and improve the wellness and health conditions of the elderly. However, their adoption and use by older adults is still a major challenge. User Experience (UX) evaluations aim at aiding on this task, by identifying the experience that a user has while interacting with an AAL technology under particular conditions. This may help designing better products and improve user engagement and adoption of AAL solutions. However, evaluating the UX of AAL technologies is a difficult task, due to the inherent limitations of their subjects and of the evaluation methods. In this study, we validated the feasibility of assessing the UX of older adults while they use a cognitive stimulation application using a neural network trained to recognize pleasant and unpleasant emotions from electroencephalography (EEG) signals by contrasting our results with those of additional self-report and qualitative analysis UX evaluations. Our study results provide evidence about the feasibility of assessing the UX of older adults using a neural network that take as input the EEG signals; the classification accuracy of our neural network ranges from 60.87% to 82.61%. As future work we will conduct additional UX evaluation studies using the three different methods, in order to appropriately validate these results. Copyright © 2016 Elsevier Inc. All rights reserved.

  6. SENSITIVITY ANALYSIS BY ARTIFICIAL NEURAL NETWORK (ANN OF VARIABLES THAT INFLUENCE THE DIAGONAL TWIST IN A PAPERBOARD INDUSTRIAL MACHINE

    Directory of Open Access Journals (Sweden)

    Guinter Neutzling Schneid

    2016-01-01

    Full Text Available The dimensional stability of the paper may change due to middle exchange moisture, releasing the latent stress acquired into the manufacturing process. One result of this tension release is the diagonal curl. This study aims to conduct a sensitivity analysis of the different input’s variables of an industrial paper machine, along with some laboratory measurements, in order to identify the importance in production of paperboard quality control and relate to the property of the paper called twist. A survey was made of the production history, relating to 2012, to observe the products with the highest quality losses. From this, they were correlated with the critical points of measurement profile in the machine cross direction and consequently with the paper. It was found some changes once the variables correlated with twist, referring to the three analyzes of the profile (tender side, middle and drive side. It was revealed, from the sensitivity analysis, that the most important and sensitive variables, respectively for the tender side, middle and drive side, were total flow from the top layer, vapor pressure in the 6th group of drying cylinders and mass flow side of the bottom layer of the formation of paperboard.

  7. Operations of electric taxis to serve advance reservations by trip chaining: Sensitivity analysis on network size, customer demand and number of charging stations

    Directory of Open Access Journals (Sweden)

    Hao Wang

    2016-10-01

    Full Text Available This research investigated the performance of an Electric Taxi (ET fleet that catered solely for customers with advance reservations. In a previously related research, a customized Paired Pickup and Delivery Problem with Time Window and Charging Station (PPDPTWCS had been formulated to solve for the minimum number of taxis that would serve a fixed set of customer demand. The concept behind this fleet optimization was to chain multiple customer trips and trips to Charging Stations (CSs to form a route and assigned to a taxi driver. In this paper the sensitivity of the ET fleet’s operations with respect to network sizes, customer demand densities and number of CSs have been investigated. It also analyzed the market shares of the CSs and the occupancy of a CS over time. The results showed that, (1 the expansion of network size or the increase in customer demand density led to increase in fleet size, number of trips to the CSs and maximum occupancies at the CSs but these performance measures grew at different rates; (2 when the network size and number of CSs were fixed, an increase in customer demand density led to a better utilization of taxis in terms of more customers served per taxi and higher average revenue per taxi; (3 given the same network size and demand density, the ET fleet’s performance was relatively insensitive to the number of CSs; and (4 the usage of individual CS was affected by the number of CS and their locations; and (5 when all the ETs were fully charged at the beginning of the same shift hour, they visited the CSs in bunches when their batteries were about to run out. These findings contribute to a better understanding of the operations of the ET fleet and the CSs. They could be used for making better decisions in the planning of ET operations.

  8. Contact sensitization in dental technicians with occupational contact dermatitis. Data of the Information Network of Departments of Dermatology (IVDK) 2001-2015.

    Science.gov (United States)

    Heratizadeh, Annice; Werfel, Thomas; Schubert, Steffen; Geier, Johannes

    2018-01-12

    Dental technicians (DTs) are at increased risk for allergic contact sensitization. To assess the current spectrum of occupational sensitization in DTs with occupational contact dermatitis (OCD). A retrospective analysis of Information Network of Departments of Dermatology patch test data from the years 2001-2015 concerning DTs with OCD was performed. Patients of the study group (226 DTs with OCD) were significantly more often diagnosed with allergic contact dermatitis (37.6% versus 18.5%; p = 0.0002) than patients of the control group (124 DTs without OCD). In the study group, positive reactions were most frequently observed to methacrylates and/or acrylates (n = 67). Of these, 61 patients showed positive reactions to at least one of the five most frequent allergens in this group, namely 2-hydroxyethyl methacrylate, 2-hydroxypropyl methacrylate, methyl methacrylate, ethyl methacrylate, and/or ethylene glycol dimethacrylate. In contrast, no positive reactions to diurethane dimethacrylate (DUDMA) occurred. Among allergens of the German Contact Dermatitis Research Group series 'dental metals', positive reactions were less frequent and were mainly to palladium chloride (n = 6). The present data analysis showed that the sensitization spectrum and spectrum of cross-reactivity are largely unchanged as compared with the 1990s. It can be concluded that test recommendations are still valid and useful, except for the methacrylate DUDMA, which could be omitted. © 2018 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  9. A comprehensive zero-copy architecture for high performance distributed Data Acquisition over advanced network technologies for the CMS experiment

    CERN Document Server

    Bauer, Gerry; Branson, James; Bukowiec, Sebastian Czeslaw; Chaze, Olivier; Cittolin, Sergio; Coarasa, J. A; Deldicque, Christian; Dobson, Marc; Dupont, Aymeric; Erhan, Samim; Gigi, Dominique; Glege, Frank; Gomez-Reino, R; Hartl, Christian; Holzner, Andre Georg; Masetti, Lorenzo; Meijers, Franciscus; Meschi, Emilio; Mommsen, Remigius; Nunez-Barranco, C; O'Dell, Vivian; Orsini, Luciano; Paus, Christoph Maria Ernst; Petrucci, Andrea; Pieri, Marco; Polese, Giovanni; Racz, Attila; Raginel, Olivier; Sakulin, Hannes; Sani, Matteo; Schwick, Christoph; Spataru, Andrei Cristian; Stoeckli, Fabian; Sumorok, Konstanty

    2013-01-01

    This paper outlines a software architecture where zero-copy operations are used comprehensively at every processing point from the Application layer to the Physical layer. The proposed architecture is being used during feasibility studies on advanced networking technologies for the CMS experiment at CERN. The design relies on a homogeneous peer-to-peer message passing system, which is built around memory pool caches allowing efficient and deterministic latency handling of messages of any size through the different software layers. In this scheme portable distributed applications can be programmed to process input to output operations by mere pointer arithmetic and DMA operations only. The approach combined with the open fabric protocol stack (OFED) allows one to attain near wire-speed message transfer at application level. The architecture supports full portability of user applications by encapsulating the protocol details and network into modular peer transport services whereas a transparent replacement of t...

  10. Sport psychological associations role to create growth and stimulate networking in sports, federations and academia - experiences from Sweden and Denmark

    DEFF Research Database (Denmark)

    Becker-Larsen, Astrid; Edvardsson, Arne

    of SIPF or DIFO. The association’s goals are to promote and develop sports psychology research, teaching and applied practice by gathering experiences from different practitioners (e.g., academia, federations and sports). Therfore, it is in both assocations intrest to come togheter and discuss the past...... and networkning in sports, federations and academia. Metod/Method Board members from DIFO and SIPF have been invited to participate in this symposium. To initate discussion the participants have been given the assignment to answer the 3 open questions regarding their association: “What have you done in the past...... directions for future growth and networking opportunities. Resultat/Results The ideas and future direction regarding growth and networking in sport psychology discussed in this symposium will be summarized in a shared guideline document. Diskussion och slutsatser/Discussion and conclusions For the continued...

  11. The College Football Student-Athlete's Academic Experience: Network Analysis and Model Development

    Science.gov (United States)

    Young, Kyle McLendon

    2010-01-01

    A grounded theory research study employing network analysis as a means of facilitating the latter stages of the coding process was conducted at a selective university that competes at the highest level of college football. The purpose of the study was to develop a better understanding of how interactive dynamics and controlling mechanisms, such as…

  12. Modernization of the french early warning network in IRSN, experience feedback and perspectives

    Energy Technology Data Exchange (ETDEWEB)

    Debayle, C.; Bardet, A.; Beguin-Leprieur, M.; Chevreuil, M.; Malfait, V.; Mechenet, V. [PRP-ENV/SESURE/LS2A (France)

    2014-07-01

    Developed few years after the Chernobyl accident in 1991, the French early warning network, Teleray, composed by 160 ambient dose equivalent rate probes, had operated for 15 years. It was decided in 2007 to modernize this facility in order to keep the infrastructure up-to-date. The sensors, the data transmission network and the supervising system were considered separately, but each development took care about the modularity of the final IT system. After a benchmarking period and technical choices, a five years project started with the aim to increase the number of probes to 420, especially around the French nuclear facilities, to change the technology and the IT system including a new data transmission network. The project kick-off was planned in june 2011, but due to the Fukushima accident, the French government asked IRSN to implement a probe on the roof of the French embassy in Tokyo on March 18, 2011. Results and feedback will be discussed, focusing on new approach about data analysis purpose. In 2014, the modernization of this network will be finished one year before it was expected and with significant cost savings. All the relevant phase of the project will be described, including time schedule and economical aspects, with the aim to describe how it is now considered fundamental to have complementary mobile systems in case of nuclear crisis. Document available in abstract form only. (authors)

  13. The neural code in developing cultured networks: experiments and advanced simulation models

    NARCIS (Netherlands)

    Rutten, Wim; Gritsun, T.; Stoyanova, Irina; le Feber, Jakob

    2012-01-01

    Understanding the neural code of cultured neuronal networks may help to forward our understanding of human brain processes.The most striking property of spontaneously firing cultures is their regular bursting activity, a burst being defined as synchronized firing of groups of neurons spread

  14. Work Study Program Provides Revenue to School and Experience to Students: Cristo Rey Network, Nationwide

    Science.gov (United States)

    Stewart, Sarah

    2016-01-01

    Thirty-two Catholic Cristo Rey schools, all independently owned and operated, serve 9,953 students in grades 9-12. Cristo Rey calls itself "the largest network of high schools in the United States whose enrollment is limited to low-income youth." Students' average family income is $35,000; 97 percent are students of color. To fund the…

  15. Ethernet Networks for Real-Time Use in the ATLAS Experiment

    CERN Document Server

    Meirosu, C; Martin, B

    2005-01-01

    Ethernet became today's de-facto standard technology for local area networks. Defined by the IEEE 802.3 and 802.1 working groups, the Ethernet standards cover technologies deployed at the first two layers of the OSI protocol stack. The architecture of modern Ethernet networks is based on switches. The switches are devices usually built using a store-and-forward concept. At the highest level, they can be seen as a collection of queues and mathematically modelled by means of queuing theory. However, the traffic profiles on modern Ethernet networks are rather different from those assumed in classical queuing theory. The standard recommendations for evaluating the performance of network devices define the values that should be measured but do not specify a way of reconciling these values with the internal architecture of the switches. The introduction of the 10 Gigabit Ethernet standard provided a direct gateway from the LAN to the WAN by the means of the WAN PHY. Certain aspects related to the actual use of WAN ...

  16. EXPERIMENT BASED FAULT DIAGNOSIS ON BOTTLE FILLING PLANT WITH LVQ ARTIFICIAL NEURAL NETWORK ALGORITHM

    Directory of Open Access Journals (Sweden)

    Mustafa DEMETGÜL

    2008-01-01

    Full Text Available In this study, an artificial neural network is developed to find an error rapidly on pneumatic system. Also the ANN prevents the system versus the failure. The error on the experimental bottle filling plant can be defined without any interference using analog values taken from pressure sensors and linear potentiometers. The sensors and potentiometers are placed on different places of the plant. Neural network diagnosis faults on plant, where no bottle, cap closing cylinder B is not working, bottle cap closing cylinder C is not working, air pressure is not sufficient, water is not filling and low air pressure faults. The fault is diagnosed by artificial neural network with LVQ. It is possible to find an failure by using normal programming or PLC. The reason offing Artificial Neural Network is to give a information where the fault is. However, ANN can be used for different systems. The aim is to find the fault by using ANN simultaneously. In this situation, the error taken place on the pneumatic system is collected by a data acquisition card. It is observed that the algorithm is very capable program for many industrial plants which have mechatronic systems.

  17. Wireless Sensor Networks--A Hands-On Modular Experiments Platform for Enhanced Pedagogical Learning

    Science.gov (United States)

    Taslidere, E.; Cohen, F. S.; Reisman, F. K.

    2011-01-01

    This paper presents the use of wireless sensor networks (WSNs) in educational research as a platform for enhanced pedagogical learning. The aim here with the use of a WSN platform was to go beyond the implementation stage to the real-life application stage, i.e., linking the implementation to real-life applications, where abstract theory and…

  18. Generation of Source Data for Experiments with Network Attack Detection Software

    Science.gov (United States)

    Kotenko, Igor; Chechulin, Andrey; Branitskiy, Alexander

    2017-03-01

    The paper suggests a new approach for traffic generation and the architecture of the software tool for evaluation of attack detection and response mechanisms. To assess the proposed approach the automatic network attack detection and response mechanism Threshold Random Walk (TRW) was chosen and implemented. The results of evaluation of this mechanism by the proposed software tool are presented.

  19. First experiences with Personal Networks as an enabling platform for service providers

    NARCIS (Netherlands)

    Hartog, F.T.H. den; Blom, M.A.; Lageweg, C.R.; Peeters, E.M.; Schmidt, J.R.; Veer, R. van der; Veldhuis, R.N.J.; Baken, N.H.G.; Selgert, F.; Vries, A. de; Werff, M.R. van der; Tao, Q.

    2007-01-01

    By developing demonstrators and performing small-scale user trials, we found various opportunities and pitfalls for deploying Personal Networks (PNs) on a commercial basis. The demonstrators were created using as many as possible legacy devices and proven technologies. They deal with applications in

  20. Sensitivity to reward and punishment in major depressive disorder: effects of rumination and of single versus multiple experiences.

    Science.gov (United States)

    Whitmer, Anson J; Frank, Michael J; Gotlib, Ian H

    2012-01-01

    In the current study, we examined the postulation that rumination makes it difficult for depressed individuals to learn the exact probability that different stimuli will be associated with punishment. To do so, we induced rumination or distraction in depressed and never-depressed participants and then measured punishment and reward sensitivity with a probabilistic selection task. In this task, participants first learn the probability that different stimuli will be associated with reward and punishment. During a subsequent test phase in which novel combinations of stimuli are presented, participants' sensitivity to reward is tested by measuring their tendency to select the stimuli that were most highly rewarded during training, and their sensitivity to punishment is tested by measuring their tendency to not select the stimuli that were most highly punished during training. Compared with distraction, rumination led depressed participants to be less sensitive to the probability that stimuli will be associated with punishment and relatively less sensitive to punishment than reward. Never-depressed participants and depressed participants who were distracted from rumination were as sensitive to reward as they were to punishment. The effects of rumination on sensitivity to punishment may be a mechanism by which rumination can lead to maladaptive consequences.

  1. Social networking experiences on Facebook: A survey of gender differences amongst students

    Directory of Open Access Journals (Sweden)

    Melanie Wiese

    2014-02-01

    Full Text Available Orientation: Students’ membership and participation in social networking sites, such as Facebook, has increased in recent years.Research purpose: The study examined students’ access to social network sites and compared male and female students’ usage of Facebook with regards to time commitment, privacy concerns, and the creation and/or maintenance of relationships.Motivation: The study adds to the existing academic literature on this topic by providing a South African perspective.Research design, approach and method: Two-hundred self-administered questionnaires were distributed using convenience sampling. The statistical analysis that was used included Mann-Whitney U-test, t-test and ANOVA analysis.Main findings: Students connect to social networking sites everyday primarily via their mobile phones. Female students reported spending more time on Facebook whilst at the same time expressing more concern for their privacy. Moreover, students were found to use Facebook to maintain existing offline friendships more so than creating new relationships.Managerial implications: Social networking sites such as Facebook play an important role in students’ everyday interpersonal communication. Practically, Facebook provides lecturers, parents and businesses the opportunity to communicate with students in a fast and cost-effective way. Therefore, insight into the variables studied could help marketers and Social Network Site operators to manage privacy concerns in order to effectively target, advertise and communicate with students.Contribution: Although past research has concentrated on the study of Facebook in terms of privacy and members’ uses little research has been conducted on gender differences in this regard, more so within a South African context. Furthermore demographic variables such as gender influence motives and behaviour, as such making the analysis demographics essential.

  2. Peru Subduction Zone Seismic Experiment (PeruSZE): Preliminary Results From a Seismic Network Between Mollendo and Lake Titicaca, Peru.

    Science.gov (United States)

    Guy, R.; Stubailo, I.; Skinner, S.; Phillips, K.; Foote, E.; Lukac, M.; Aguilar, V.; Tavera, H.; Audin, L.; Husker, A.; Clayton, R.; Davis, P. M.

    2008-12-01

    This work describes preliminary results from a 50 station broadband seismic network recently installed from the coast to the high Andes in Peru. UCLA's Center for Embedded Network Sensing (CENS) and Caltech's Tectonic Observatory are collaborating with the IRD (French L'Institut de Recherche pour le Developpement) and the Institute of Geophysics, in Lima Peru in a broadband seismic experiment that will study the transition from steep to shallow slab subduction. The currently installed line has stations located above the steep subduction zone at a spacing of about 6 km. In 2009 we plan to install a line of 50 stations north from this line along the crest of the Andes, crossing the transition from steep to shallow subduction. A further line from the end of that line back to the coast, completing a U shaped array, is in the planning phase. The network is wirelessly linked using multi-hop network software designed by computer scientists in CENS in which data is transmitted from station to station, and collected at Internet drops, from where it is transmitted over the Internet to CENS each night. The instrument installation in Peru is almost finished and we have been receiving data daily from 10 stations (out of total 50) since June 2008. The rest are recording on-site while the RF network is being completed. The software system provides dynamic link quality based routing, reliable data delivery, and a disruption tolerant shell interface for managing the system from UCLA without the need to travel to Peru. The near real-time data delivery also allows immediate detection of any problems at the sites. We are building a seismic data and GPS quality control toolset that would greatly minimize the station's downtime by alerting the users of any possible problems.

  3. Social networks, social support and social negativity: A qualitative study of head and neck cancer caregivers' experiences.

    Science.gov (United States)

    Balfe, M; Keohane, K; O'Brien, K; Sharp, L

    2017-11-01

    Head and neck cancer is a serious form of cancer that can generate substantial physical and psychosocial morbidity. Informal caregivers can help patients to manage head and neck cancer and its emotional impacts, both during and after treatment. Caregivers, however, can experience considerable stress as a result of their caring activities. Supportive relationships can protect caregivers from psychosocial strain. Thirty-one head and neck cancer caregivers were interviewed about their experiences of accessing social support from their social networks; difficulties that they experienced accessing this support; and strategies that they used to address these difficulties. Results suggest that head and neck cancer caregivers strongly value social support, but can find it difficult to obtain, and a number of them experience socially negative responses from their networks. Some carers attempt to answer or supplement support deficiencies by turning to non-human coping supports, such as pets, spiritual figures or medication. Implications for theory and practice are discussed. © 2016 John Wiley & Sons Ltd.

  4. European Network of Trainees in Obstetrics and Gynaecology: experiences from the 2016 exchange programme in Turin, Italy.

    Science.gov (United States)

    Eismann, Sabine; Brandl, Mario; Spinnewijn, Laura; Everden, Caroline; Campolo, Federica; Schott, Sarah

    2017-02-01

    The European Network of Trainees in Obstetrics and Gynaecology (ENTOG) is an organization representing trainees from 30 European member countries. Together with the European Board and College of Obstetrics and Gynaecology (EBCOG), it seeks to achieve the highest possible standards of training and consequently to improve the quality of medical care in the field of gynaecology and obstetrics. Every year, the ENTOG council meets and holds a scientific meeting in a different European country. To coincide with this, the host country arranges an exchange, to which each member country can send two trainees. This exchange allows trainees to gain insight into both daily clinical work and the structure of the health care system. This article reports the experiences of participants in the May 2016 ENTOG exchange to Turin, Italy. The aim is to outline differences in training between Germany and Italy as well as some striking differences with other European countries. The participants' personal benefit from this unique experience was not only to get familiar with the Italian trainee programme and health care system, but also to exchange experiences among representatives from other European countries and build up a young gynaecological network within Europe.

  5. Sensitive and specific peak detection for SELDI-TOF mass spectrometry using a wavelet/neural-network based approach.

    Directory of Open Access Journals (Sweden)

    Vincent A Emanuele

    Full Text Available SELDI-TOF mass spectrometer's compact size and automated, high throughput design have been attractive to clinical researchers, and the platform has seen steady-use in biomarker studies. Despite new algorithms and preprocessing pipelines that have been developed to address reproducibility issues, visual inspection of the results of SELDI spectra preprocessing by the best algorithms still shows miscalled peaks and systematic sources of error. This suggests that there continues to be problems with SELDI preprocessing. In this work, we study the preprocessing of SELDI in detail and introduce improvements. While many algorithms, including the vendor supplied software, can identify peak clusters of specific mass (or m/z in groups of spectra with high specificity and low false discover rate (FDR, the algorithms tend to underperform estimating the exact prevalence and intensity of peaks in those clusters. Thus group differences that at first appear very strong are shown, after careful and laborious hand inspection of the spectra, to be less than significant. Here we introduce a wavelet/neural network based algorithm which mimics what a team of expert, human users would call for peaks in each of several hundred spectra in a typical SELDI clinical study. The wavelet denoising part of the algorithm optimally smoothes the signal in each spectrum according to an improved suite of signal processing algorithms previously reported (the LibSELDI toolbox under development. The neural network part of the algorithm combines those results with the raw signal and a training dataset of expertly called peaks, to call peaks in a test set of spectra with approximately 95% accuracy. The new method was applied to data collected from a study of cervical mucus for the early detection of cervical cancer in HPV infected women. The method shows promise in addressing the ongoing SELDI reproducibility issues.

  6. Ultrahigh-sensitive sensing platform based on p-type dumbbell-like Co3O4 network

    Science.gov (United States)

    Zhou, Tingting; Zhang, Tong; Zhang, Rui; Lou, Zheng; Deng, Jianan; Wang, Lili

    2017-12-01

    Development of high performance room temperature sensors remains a grand challenge for high demand of practical application. Metal oxide semiconductors (MOSs) have many advantages over others due to their easy functionalization, high surface area, and low cost. However, they typically need a high work temperature during sensing process. Here, p-type sensing layer is reported, consisting of pore-rich dumbbell-like Co3O4 particles (DP-Co3O4) with intrinsic high catalytic activity. The gas sensor (GS) based DP-Co3O4 catalyst exhibits ultrahigh NH3 sensing activity along with excellent stability over other structure based NH3 GSs in room temperature work environment. In addition, the unique structure of DP-Co3O4 with pore-rich and high catalytic activity endows fast gas diffusion rate and high sensitivity at room temperature. Taken together, the findings in this work highlight the merit of integrating highly active materials in p-type materials, offering a framework to develop high-sensitivity room temperature sensing platforms.

  7. Application of Bayesian neural networks to energy reconstruction in EAS experiments for ground-based TeV astrophysics

    Science.gov (United States)

    Bai, Y.; Xu, Y.; Pan, J.; Lan, J. Q.; Gao, W. W.

    2016-07-01

    A toy detector array is designed to detect a shower generated by the interaction between a TeV cosmic ray and the atmosphere. In the present paper, the primary energies of showers detected by the detector array are reconstructed with the algorithm of Bayesian neural networks (BNNs) and a standard method like the LHAASO experiment [1], respectively. Compared to the standard method, the energy resolutions are significantly improved using the BNNs. And the improvement is more obvious for the high energy showers than the low energy ones.

  8. Using social networking sites (namely Facebook) in health visiting practice--an account of five years experience.

    Science.gov (United States)

    Dion, Xena

    2015-02-01

    With new developments in electronic and social networking communication methods the way health visitors communicate with clients is rapidly changing. With good governance these technologies can be utilised to enhance the health visiting service and can be an effective way of accessing hard-to-reach families, saving time and resources. This paper presents five years' experience in the use of Facebook between the health visiting team and clients and explains the benefits and potential it offers to health visitors and other community practitioners.

  9. Closed-loop neuro-robotic experiments to test computational properties of neuronal networks.

    Science.gov (United States)

    Tessadori, Jacopo; Chiappalone, Michela

    2015-03-02

    Information coding in the Central Nervous System (CNS) remains unexplored. There is mounting evidence that, even at a very low level, the representation of a given stimulus might be dependent on context and history. If this is actually the case, bi-directional interactions between the brain (or if need be a reduced model of it) and sensory-motor system can shed a light on how encoding and decoding of information is performed. Here an experimental system is introduced and described in which the activity of a neuronal element (i.e., a network of neurons extracted from embryonic mammalian hippocampi) is given context and used to control the movement of an artificial agent, while environmental information is fed back to the culture as a sequence of electrical stimuli. This architecture allows a quick selection of diverse encoding, decoding, and learning algorithms to test different hypotheses on the computational properties of neuronal networks.

  10. European experience on air and water pollution control: monitoring network and warning station

    Energy Technology Data Exchange (ETDEWEB)

    Aflalo, Sergio S. [Groupe Environnement S.A., Poissy (France)

    1993-12-31

    After a review of the energy consumption and pollutants emitted in the European Community, especially those concerning the `green house effect`, the author proceeded a summary of the actual legislation and Europeans directives, and also, the Best Available Technology for reducing air pollution is discussed. Original Air Quality monitoring networks performed by Environnement SA are described including measurements obtained around Paris and other areas of France. 7 refs., 11 figs.

  11. Social networking experiences on Facebook: A survey of gender differences amongst students

    Directory of Open Access Journals (Sweden)

    Melanie Wiese

    2014-11-01

    Research purpose: The study examined students’ access to social network sites and compared male and female students’ usage of Facebook with regards to time commitment, privacy concerns, and the creation and/or maintenance of relationships. Motivation: The study adds to the existing academic literature on this topic by providing a South African perspective. Research design, approach and method: Two-hundred self-administered questionnaires were distributed using convenience sampling. The statistical analysis that was used included Mann-Whitney U-test, t-test and ANOVA analysis. Main findings: Students connect to social networking sites everyday primarily via their mobile phones. Female students reported spending more time on Facebook whilst at the same time expressing more concern for their privacy. Moreover, students were found to use Facebook to maintain existing offline friendships more so than creating new relationships. Managerial implications: Social networking sites such as Facebook play an important role in students’ everyday interpersonal communication. Practically, Facebook provides lecturers, parents and businesses the opportunity to communicate with students in a fast and cost-effective way. Therefore, insight into the variables studied could help marketers and Social Network Site operators to manage privacy concerns in order to effectively target, advertise and communicate with students. Contribution: Although past research has concentrated on the study of Facebook in terms of privacy and members’ uses little research has been conducted on gender differences in this regard, more so within a South African context. Furthermore demographic variables such as gender influence motives and behaviour, as such making the analysis demographics essential.

  12. Research networks and scientific production in Economics: The recent spanish experience (WP)

    OpenAIRE

    Duque, Juan Carlos; Ramos Lobo, Raúl; Royuela Mora, Vicente

    2007-01-01

    This paper studies Spanish scientific production in Economics from 1994 to 2004. It focuses on aspects that have received little attention in other bibliometric studies, such as the impact of research and the role of scientific collaborations in the publications produced by Spanish universities. Our results show that national research networks have played a fundamental role in the increase in Spanish scientific production in this discipline.

  13. Research networks and scientific production in Economics, The recent Spanish Experience.

    OpenAIRE

    Raul Ramos; Vicente Royuela; Juan Carlos Duque

    2007-01-01

    This paper studies Spanish scientific production in Economics from 1994 to 2004. It focuses on aspects that have received little attention in other bibliometric studies, such as the impact of research and the role of scientific collaborations in the publications produced by Spanish universities. Our results show that national research networks have played a fundamental role in the increase in Spanish scientific production in this discipline. The outcome of this research is an invitation to un...

  14. Undergraduate Students' Development of Social, Cultural, and Human Capital in a Networked Research Experience

    Science.gov (United States)

    Thompson, Jennifer Jo; Conaway, Evan; Dolan, Erin L.

    2016-01-01

    Recent calls for reform in undergraduate biology education have emphasized integrating research experiences into the learning experiences of all undergraduates. Contemporary science research increasingly demands collaboration across disciplines and institutions to investigate complex research questions, providing new contexts and models for…

  15. Experiment and Artificial Neural Network Prediction of Thermal Conductivity and Viscosity for Alumina-Water Nanofluids.

    Science.gov (United States)

    Zhao, Ningbo; Li, Zhiming

    2017-05-19

    To effectively predict the thermal conductivity and viscosity of alumina (Al₂O₃)-water nanofluids, an artificial neural network (ANN) approach was investigated in the present study. Firstly, using a two-step method, four Al₂O₃-water nanofluids were prepared respectively by dispersing different volume fractions (1.31%, 2.72%, 4.25%, and 5.92%) of nanoparticles with the average diameter of 30 nm. On this basis, the thermal conductivity and viscosity of the above nanofluids were analyzed experimentally under various temperatures ranging from 296 to 313 K. Then a radial basis function (RBF) neural network was constructed to predict the thermal conductivity and viscosity of Al₂O₃-water nanofluids as a function of nanoparticle volume fraction and temperature. The experimental results showed that both nanoparticle volume fraction and temperature could enhance the thermal conductivity of Al₂O₃-water nanofluids. However, the viscosity only depended strongly on Al₂O₃ nanoparticle volume fraction and was increased slightly by changing temperature. In addition, the comparative analysis revealed that the RBF neural network had an excellent ability to predict the thermal conductivity and viscosity of Al₂O₃-water nanofluids with the mean absolute percent errors of 0.5177% and 0.5618%, respectively. This demonstrated that the ANN provided an effective way to predict the thermophysical properties of nanofluids with limited experimental data.

  16. A cross-sectional evaluation of meditation experience on electroencephalography data by artificial neural network and support vector machine classifiers.

    Science.gov (United States)

    Lee, Yu-Hao; Hsieh, Ya-Ju; Shiah, Yung-Jong; Lin, Yu-Huei; Chen, Chiao-Yun; Tyan, Yu-Chang; GengQiu, JiaCheng; Hsu, Chung-Yao; Chen, Sharon Chia-Ju

    2017-04-01

    To quantitate the meditation experience is a subjective and complex issue because it is confounded by many factors such as emotional state, method of meditation, and personal physical condition. In this study, we propose a strategy with a cross-sectional analysis to evaluate the meditation experience with 2 artificial intelligence techniques: artificial neural network and support vector machine. Within this analysis system, 3 features of the electroencephalography alpha spectrum and variant normalizing scaling are manipulated as the evaluating variables for the detection of accuracy. Thereafter, by modulating the sliding window (the period of the analyzed data) and shifting interval of the window (the time interval to shift the analyzed data), the effect of immediate analysis for the 2 methods is compared. This analysis system is performed on 3 meditation groups, categorizing their meditation experiences in 10-year intervals from novice to junior and to senior. After an exhausted calculation and cross-validation across all variables, the high accuracy rate >98% is achievable under the criterion of 0.5-minute sliding window and 2 seconds shifting interval for both methods. In a word, the minimum analyzable data length is 0.5 minute and the minimum recognizable temporal resolution is 2 seconds in the decision of meditative classification. Our proposed classifier of the meditation experience promotes a rapid evaluation system to distinguish meditation experience and a beneficial utilization of artificial techniques for the big-data analysis.

  17. Caries experience in 15-year-old school children in Bangalore with inherited taste sensitivity levels to 6-n-propylthiouracil: an observational study.

    Science.gov (United States)

    Jyothirmai, Jaddu; Naganandini, Sampathkumar; Aradhya, Shankar

    2011-02-01

      The relationship between sugar consumption and caries has been researched extensively for many years. The individual drive for the consumption of sweet food is controlled by a variety of biologic, psychologic, and sociologic factors. Sweet preference has been linked to bitter taste sensitivity to 6-n-propylthiouracil, a heritable trait. The present study investigates the association between inherited taste sensitivity to 6-n-popylthiouracil and dental caries experience in 15-year-old school children.   Two hundred 15-year-old school children from randomly selected schools in Bangalore, India, participated in the study. Data were collected regarding demographic factors and socioeconomic status by personal interviews with the children. Sensitivity to 6-n-propylthiouracil was determined using Tepper filter paper method, and the responses were recorded on the labeled magnitude scale. Each child was examined thoroughly for oral hygiene status and caries experience. Appropriate statistical tests, such as chi-squared test, Fisher's exact test, and Kruskal-Wallis test, were used to analyze the data.   Non-tasters were significantly associated with caries experience (P caries experience. © 2011 Blackwell Publishing Asia Pty Ltd.

  18. Efficient assignment of methyl resonances: Enhanced sensitivity by gradient selection in a DE-MQ-(H)CC{sup m}Ht {sup m}-TOCSY experiment

    Energy Technology Data Exchange (ETDEWEB)

    Permi, Perttu, E-mail: perttu.permi@helsinki.fi; Tossavainen, Helena; Hellman, Maarit [University of Helsinki, NMR Laboratory, Structural Biology and Biophysics Program, Institute of Biotechnology (Finland)

    2004-11-15

    We present a gradient selected and doubly sensitivity-enhanced DE-MQ-(H)CC{sup m}H{sup m}-TOCSY experiment for the sequence-specific assignment of methyl resonances in {sup 13}C,{sup 15}N labeled proteins. The proposed experiment provides improved sensitivity and artifact suppression relative to the phase-cycled experiments. One part of the {sup 13}Cchemical shift evolution takes place under heteronuclear multiple quantum coherence, whereas the other part occurs under {sup 13}C single quantum coherence in a semi-constant time fashion. The feasibility of the experiment was assessed using {sup 15}N,{sup 13}C labeled Mus musculus coactosin (16 kDa), having a rotational correlation time of 14.5 ns at 15 deg. D{sub 2}O. A 16-h experiment on 600 MHz {sup 1}H yielded good quality data and enabled the assignment of 70 out of 72 methyl groups in coactosin. As well as being an improved approach for methyl resonance assignment, this experiment can also be highly valuable for the rapid assignment of methyl resonances in SAR by NMR studies.

  19. Occupational contact sensitization in female geriatric nurses: Data of the Information Network of Departments of Dermatology (IVDK) 2005-2014.

    Science.gov (United States)

    Schubert, S; Bauer, A; Molin, S; Skudlik, C; Geier, J

    2017-03-01

    Geriatric nurses (GN) have a high risk of occupational contact dermatitis (OCD), with chronic irritant contact dermatitis predominating. However, allergic contact dermatitis is an important issue as well. Little is known whether the relevant occupational allergen spectrum reported in the 1990s, including fragrances, preservatives, rubber chemicals and ingredients of surface disinfectants to be the most common sensitizers in GN, is still valid. To monitor the current allergen spectrum in GN with OCD and verify the validity of the patch test recommendations (baseline-, preservative-, ointment base-, rubber-, disinfectant, series and fragrances) in GN with suspected OCD given by the German Contact Dermatitis Research Group (DKG). Retrospective analysis of IVDK data (2005-2014) of 743 female GN with OCD, in comparison to 695 GN without OCD. GN with OCD reacted significantly more frequently to both fragrance mixes, hydroxyisohexyl 3-cyclohexene carboxaldehyde (HICC), thiuram mix, zinc diethyldithiocarbamate and mercaptobenzothiazole than GN without OCD. Reactions to MDBGN, methylchloroisothiazolinone/methylisothiazolinone and oil of turpentine occurred substantially, but not significantly more frequently among GN with OCD. The latter may be due to former use of a special alcoholic liniment in geriatric care. Among material from the patients' workplaces, tetrazepam was a frequent allergen, due to dust exposure from pill crushing. Furthermore, occupationally used protective gloves, body care products as well as surface disinfectants were often tested positively. The general allergen spectrum in GN with OCD is unchanged, so the DKG patch test recommendations are still valid. Prevention of occupational sensitization should focus on fragrance-free hygiene and body care products, usage of accelerator-free protective gloves and avoidance of drug dust exposure. © 2016 European Academy of Dermatology and Venereology.

  20. Trichoplax adhaerens reveals a network of nuclear receptors sensitive to 9-cis-retinoic acid at the base of metazoan evolution

    Directory of Open Access Journals (Sweden)

    Jan Philipp Novotný

    2017-09-01

    Full Text Available Trichoplax adhaerens, the only known species of Placozoa is likely to be closely related to an early metazoan that preceded branching of Cnidaria and Bilateria. This animal species is surprisingly well adapted to free life in the World Ocean inhabiting tidal costal zones of oceans and seas with warm to moderate temperatures and shallow waters. The genome of T. adhaerens (sp. Grell includes four nuclear receptors, namely orthologue of RXR (NR2B, HNF4 (NR2A, COUP-TF (NR2F and ERR (NR3B that show a high degree of similarity with human orthologues. In the case of RXR, the sequence identity to human RXR alpha reaches 81% in the DNA binding domain and 70% in the ligand binding domain. We show that T. adhaerens RXR (TaRXR binds 9-cis retinoic acid (9-cis-RA with high affinity, as well as high specificity and that exposure of T. adhaerens to 9-cis-RA regulates the expression of the putative T. adhaerens orthologue of vertebrate L-malate-NADP+ oxidoreductase (EC 1.1.1.40 which in vertebrates is regulated by a heterodimer of RXR and thyroid hormone receptor. Treatment by 9-cis-RA alters the relative expression profile of T. adhaerens nuclear receptors, suggesting the existence of natural ligands. Keeping with this, algal food composition has a profound effect on T. adhaerens growth and appearance. We show that nanomolar concentrations of 9-cis-RA interfere with T. adhaerens growth response to specific algal food and causes growth arrest. Our results uncover an endocrine-like network of nuclear receptors sensitive to 9-cis-RA in T. adhaerens and support the existence of a ligand-sensitive network of nuclear receptors at the base of metazoan evolution.

  1. Trichoplax adhaerens reveals a network of nuclear receptors sensitive to 9-cis-retinoic acid at the base of metazoan evolution.

    Science.gov (United States)

    Novotný, Jan Philipp; Chughtai, Ahmed Ali; Kostrouchová, Markéta; Kostrouchová, Veronika; Kostrouch, David; Kaššák, Filip; Kaňa, Radek; Schierwater, Bernd; Kostrouchová, Marta; Kostrouch, Zdenek

    2017-01-01

    Trichoplax adhaerens, the only known species of Placozoa is likely to be closely related to an early metazoan that preceded branching of Cnidaria and Bilateria. This animal species is surprisingly well adapted to free life in the World Ocean inhabiting tidal costal zones of oceans and seas with warm to moderate temperatures and shallow waters. The genome of T. adhaerens (sp. Grell) includes four nuclear receptors, namely orthologue of RXR (NR2B), HNF4 (NR2A), COUP-TF (NR2F) and ERR (NR3B) that show a high degree of similarity with human orthologues. In the case of RXR, the sequence identity to human RXR alpha reaches 81% in the DNA binding domain and 70% in the ligand binding domain. We show that T. adhaerens RXR (TaRXR) binds 9-cis retinoic acid (9-cis-RA) with high affinity, as well as high specificity and that exposure of T. adhaerens to 9-cis-RA regulates the expression of the putative T. adhaerens orthologue of vertebrate L-malate-NADP+ oxidoreductase (EC 1.1.1.40) which in vertebrates is regulated by a heterodimer of RXR and thyroid hormone receptor. Treatment by 9-cis-RA alters the relative expression profile of T. adhaerens nuclear receptors, suggesting the existence of natural ligands. Keeping with this, algal food composition has a profound effect on T. adhaerens growth and appearance. We show that nanomolar concentrations of 9-cis-RA interfere with T. adhaerens growth response to specific algal food and causes growth arrest. Our results uncover an endocrine-like network of nuclear receptors sensitive to 9-cis-RA in T. adhaerens and support the existence of a ligand-sensitive network of nuclear receptors at the base of metazoan evolution.

  2. Anger-sensitive networks: characterizing neural systems recruited during aggressive social interactions using data-driven analysis

    Science.gov (United States)

    Krämer, Ulrike M; Beckmann, Christian F

    2017-01-01

    Abstract Social neuroscience uses increasingly complex paradigms to improve ecological validity, as investigating aggressive interactions with functional magnetic resonance imaging (fMRI). Standard analyses for fMRI data typically use general linear models (GLM), which require a priori models of task effects on neural processes. These may inadequately model non-stimulus-locked or temporally overlapping cognitive processes, as mentalizing about other agents. We used the data-driven approach of independent component analysis (ICA) to investigate neural processes involved in a competitive interaction. Participants were confronted with an angry-looking opponent while having to anticipate the trial outcome and the opponent’s behaviour. We show that several spatially distinctive neural networks with associated temporal dynamics were modulated by the opponent’s facial expression. These results dovetail and extend the main effects observed in the GLM analysis of the same data. Additionally, the ICA approach identified effects of the experimental condition on neural systems during inter-trial intervals. We demonstrate that cognitive processes during aggressive interactions are poorly modelled by simple stimulus onset/duration variables and instead have more complex temporal dynamics. This highlights the utility of using data-driven analyses to elucidate the distinct cognitive processes recruited during complex social paradigms. PMID:29040743

  3. Experiences on p-Version Time-Discontinuous Galerkin's Method for Nonlinear Heat Transfer Analysis and Sensitivity Analysis

    Science.gov (United States)

    Hou, Gene

    2004-01-01

    The focus of this research is on the development of analysis and sensitivity analysis equations for nonlinear, transient heat transfer problems modeled by p-version, time discontinuous finite element approximation. The resulting matrix equation of the state equation is simply in the form ofA(x)x = c, representing a single step, time marching scheme. The Newton-Raphson's method is used to solve the nonlinear equation. Examples are first provided to demonstrate the accuracy characteristics of the resultant finite element approximation. A direct differentiation approach is then used to compute the thermal sensitivities of a nonlinear heat transfer problem. The report shows that only minimal coding effort is required to enhance the analysis code with the sensitivity analysis capability.

  4. Cyclic deformation-induced solute transport in tissue scaffolds with computer designed, interconnected, pore networks: experiments and simulations.

    Science.gov (United States)

    Den Buijs, Jorn Op; Dragomir-Daescu, Dan; Ritman, Erik L

    2009-08-01

    Nutrient supply and waste removal in porous tissue engineering scaffolds decrease from the periphery to the center, leading to limited depth of ingrowth of new tissue into the scaffold. However, as many tissues experience cyclic physiological strains, this may provide a mechanism to enhance solute transport in vivo before vascularization of the scaffold. The hypothesis of this study was that pore cross-sectional geometry and interconnectivity are of major importance for the effectiveness of cyclic deformation-induced solute transport. Transparent elastic polyurethane scaffolds, with computer-programmed design of pore networks in the form of interconnected channels, were fabricated using a 3D printing and injection molding technique. The scaffold pores were loaded with a colored tracer for optical contrast, cyclically compressed with deformations of 10 and 15% of the original undeformed height at 1.0 Hz. Digital imaging was used to quantify the spatial distribution of the tracer concentration within the pores. Numerical simulations of a fluid-structure interaction model of deformation-induced solute transport were compared to the experimental data. The results of experiments and modeling agreed well and showed that pore interconnectivity heavily influences deformation-induced solute transport. Pore cross-sectional geometry appears to be of less relative importance in interconnected pore networks. Validated computer models of solute transport can be used to design optimal scaffold pore geometries that will enhance the convective transport of nutrients inside the scaffold and the removal of waste, thus improving the cell survivability deep inside the scaffold.

  5. Assessing the Potential of Social Networks as a Means for Information Diffusion the Weatherization Experiences (WE) Project.

    Energy Technology Data Exchange (ETDEWEB)

    Rose, Erin M. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Hawkins, Beth A. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

    2015-04-01

    In April 2009, U.S. Department of Energy (DOE) formally tasked Oak Ridge National Laboratory (ORNL) with conducting two impact and process evaluations of DOE’s Weatherization Assistance Program (WAP), known as the retrospective and American Recovery and Reinvestment Act of 2009 (ARRA) period evaluations, respectively. The former focused on WAP Program Year (PY) 2008, which covers the period from April 2008 to June 2009. The latter focused on PY 2010. This report presents in-depth analyses from ORNL’s social network study, the Weatherization Experiences (WE) Project, an exploratory study conducted as part of the ARRA period WAP evaluation. The WE Project explored the potential for WAP recipients and staff to influence energy savings beyond their homes and day jobs. Several studies conducted through ORNL’s evaluation of WAP found that the program has the ability to profoundly impact the lives of the people it serves (Tonn et al. 2014b). Recipients of WAP provided statements ranging from the newfound ability to pay utility bills and prescription medication to reduced emergency department visits for asthma and medical conditions associated with thermal stress. Through this exploratory research project, the stories of hundreds of weatherization recipients and providers were documented. The WE Project was designed to further investigate whether or not shared experiences with weatherization have the power to stimulate home energy saving action within an individual’s social network.

  6. INTERPERSONAL COMMUNICATION AND METHODOLOGIES OF INNOVATION. A HEURISTIC EXPERIENCE IN THE CLASSROOM APPLYING SEMANTIC NETWORKS

    Directory of Open Access Journals (Sweden)

    José Manuel Corujeira Gómez

    2014-10-01

    Full Text Available The current definition of creativity gives importance to interpersonal communication in innovation strategies, and allows us to question the profiles of professionals –innovation partners– communication skills in the practice session in which they are applied. This text shows shallow results on the application of some of their tactics with a group of students. We tested structural/procedural descriptions of hypothetical effects of communication using indicators proposed by Network Theory in terms topologies provided by the group. Without a conclusive result, we expect this paper helps to the creativity's investigation in the innovation sessions.

  7. Research networks and scientific production in Economics: The recent Spanish Experience

    Directory of Open Access Journals (Sweden)

    Vicente Royuela

    2011-04-01

    Full Text Available This paper studies Spanish scientific production in Economics from 1994 to 2004. It focuses on aspects that have received little attention in other bibliometric studies, such as the impact of research and the role of scientific collaborations in the publications produced by Spanish universities. Our results show that national research networks have played a fundamental role in the increase in Spanish scientific production in this discipline. The outcome of this research is an invitation to universities in developing countries to encourage and stimulate the practice of academic co-authorships since they increase the level, quality, impact and diffusion of scientific production.

  8. New grid based test bed environment for carrying out ad-hoc networking experiments

    CSIR Research Space (South Africa)

    Johnson, D

    2006-09-01

    Full Text Available and a Wistron CM9 mini PCI Atheros based WiFi card with 802.11a/b/g capability was used for each node. A Lego Mindstorms robot with a battery powered Soekris motherboard containing a 802.11a (5.8GHz) card and a 802.11b/g (2.4GHz) card was used... at the CSIR, South Africa (email {djohnson, ykaka, jhay}@csir.co.za) test bed [3]. These have helped understand the limitations of the 802.11 MAC layer and the issues that external factors such as hidden nodes, network load and interference have...

  9. Sensitivity of the Cherenkov Telescope Array to the detection of a dark matter signal in comparison to direct detection and collider experiments

    Science.gov (United States)

    Balázs, Csaba; Conrad, Jan; Farmer, Ben; Jacques, Thomas; Li, Tong; Meyer, Manuel; Queiroz, Farinaldo S.; Sánchez-Conde, Miguel A.

    2017-10-01

    Imaging atmospheric Cherenkov telescopes (IACTs) that are sensitive to potential γ -ray signals from dark matter (DM) annihilation above ˜50 GeV will soon be superseded by the Cherenkov Telescope Array (CTA). CTA will have a point source sensitivity an order of magnitude better than currently operating IACTs and will cover a broad energy range between 20 GeV and 300 TeV. Using effective field theory and simplified models to calculate γ -ray spectra resulting from DM annihilation, we compare the prospects to constrain such models with CTA observations of the Galactic center with current and near-future measurements at the Large Hadron Collider (LHC) and direct detection experiments. For DM annihilations via vector or pseudoscalar couplings, CTA observations will be able to probe DM models out of reach of the LHC, and, if DM is coupled to standard fermions by a pseudoscalar particle, beyond the limits of current direct detection experiments.

  10. The Role of the Meaning of Life and Religious Experience of God’s Presence and God's Absence Amongst Students with Different Levels of Conscience Sensitivity

    Directory of Open Access Journals (Sweden)

    Stanisław Głaz

    2013-02-01

    Full Text Available The aim of the author's own research was: (a defining the level of meaning in life and the level of religious experience (God's presence and God's absence in groups of students with high and low levels of conscience sensitivity and (b showing the connection between meaning in life and the level of religious experience (God's presence and God's absence in groups of students with high and low levels of conscience sensitivity. The study was conducted in 2009–2010 among university students in Kraków. The subject group consisted of students of several non-Catholic public and state universities. All participants were Polish born, culturally homogeneous, and stemmed from families of average affluence. The age of the respondents ranged from 21 to 25. Two-hundred and forty sets of correctly completed questionnaires were used for the results analysis.

  11. A Remote Sensing Data Based Artificial Neural Network Approach for Predicting Climate-Sensitive Infectious Disease Outbreaks: A Case Study of Human Brucellosis

    Directory of Open Access Journals (Sweden)

    Jiao Wang

    2017-09-01

    Full Text Available Remote sensing technologies can accurately capture environmental characteristics, and together with environmental modeling approaches, help to predict climate-sensitive infectious disease outbreaks. Brucellosis remains rampant worldwide in both domesticated animals and humans. This study used human brucellosis (HB as a test case to identify important environmental determinants of the disease and predict its outbreaks. A novel artificial neural network (ANN model was developed, using annual county-level numbers of HB cases and data on 37 environmental variables, potentially associated with HB in Inner Mongolia, China. Data from 2006 to 2008 were used to train, validate and test the model, while data for 2009–2010 were used to assess the model’s performance. The Enhanced Vegetation Index was identified as the most important predictor of HB incidence, followed by land surface temperature and other temperature- and precipitation-related variables. The suitable ecological niche of HB was modeled based on these predictors. Model estimates were found to be in good agreement with reported numbers of HB cases in both the model development and assessment phases. The study suggests that HB outbreaks may be predicted, with a reasonable degree of accuracy, using the ANN model and environmental variables obtained from satellite data. The study deepened the understanding of environmental determinants of HB and advanced the methodology for prediction of climate-sensitive infectious disease outbreaks.

  12. Building collaboration through shared actions: The experience of the Global Network for Disaster Reduction

    Directory of Open Access Journals (Sweden)

    Terry Gibson

    2012-06-01

    Full Text Available This article asks how the emergent Global Network for Disaster Reduction has built collaboration and impact. Observation of the network’s journey nuanced the researcher’s initial hypothesis in marked ways. A ‘reflective practitioner’ perspective is adopted, locating action within two relevant theoretical frameworks to aid understanding and define future progress. Development showed an early emphasis on a ‘community of practice’ model. However, this appeared ineffective in creating the intended collaboration and led to the recognition of the power of shared action. This observation is framed within the thinking of Freire (1996 on action and reflection as a means of empowerment. The political dimension of the network’s activity is recognised, and is related to Gaventa’s (1980 thinking on the creation of political space. The article attempts to show that combining cycles of action and reflection in the network’s activity (i.e. creating a practitioner focus with a wider investigation of relevant literature and thinking can be helpful in framing understanding and determining future strategy. It concludes by suggesting that a proposed framework of ‘communities of praxis’ may have a broader application in the development of networks.

  13. Blood Pressure Genetic Risk Score Predicts Blood Pressure Responses to Dietary Sodium and Potassium: The GenSalt Study (Genetic Epidemiology Network of Salt Sensitivity).

    Science.gov (United States)

    Nierenberg, Jovia L; Li, Changwei; He, Jiang; Gu, Dongfeng; Chen, Jichun; Lu, Xiangfeng; Li, Jianxin; Wu, Xigui; Gu, C Charles; Hixson, James E; Rao, Dabeeru C; Kelly, Tanika N

    2017-12-01

    We examined the association between genetic risk score (GRS) for blood pressure (BP), based on single nucleotide polymorphisms identified in previous BP genome-wide association study meta-analyses, and salt and potassium sensitivity of BP among participants of the GenSalt study (Genetic Epidemiology Network of Salt Sensitivity). The GenSalt study was conducted among 1906 participants who underwent a 7-day low-sodium (51.3 mmol sodium/d), 7-day high-sodium (307.8 mmol sodium/d), and 7-day high-sodium plus potassium (60 mmol potassium/d) intervention. BP was measured 9× at baseline and at the end of each intervention period using a random zero sphygmomanometer. Associations between systolic BP (SBP), diastolic BP, and mean arterial pressure GRS and respective SBP, diastolic BP, and mean arterial pressure responses to the dietary interventions were assessed using mixed linear regression models that accounted for familial dependencies and adjusted for age, sex, field center, body mass index, and baseline BP. As expected, baseline SBP, diastolic BP, and mean arterial pressure significantly increased per quartile increase in GRS (P=2.7×10-8, 9.8×10-8, and 6.4×10-6, respectively). In contrast, increasing GRS quartile conferred smaller SBP, diastolic BP, and mean arterial pressure responses to the low-sodium intervention (P=1.4×10-3, 0.02, and 0.06, respectively) and smaller SBP responses to the high-sodium and potassium interventions (P=0.10 and 0.05). In addition, overall findings were similar when examining GRS as a continuous measure. Contrary to our initial hypothesis, we identified an inverse relationship between BP GRS and salt and potassium sensitivity of BP. These data may provide novel implications on the relationship between BP responses to dietary sodium and potassium and hypertension. © 2017 American Heart Association, Inc.

  14. Comparison of ozone uptake and sensitivity between a phytotron study with young beech and a field experiment with adult beech (Fagus sylvatica)

    Energy Technology Data Exchange (ETDEWEB)

    Nunn, Angela J. [Ecophysiology of Plants, Department of Ecology, TU Muenchen, Am Hochanger 13, D-85354 Freising (Germany)]. E-mail: nunn@wzw.tum.de; Kozovits, A.R. [Ecophysiology of Plants, Department of Ecology, TU Muenchen, Am Hochanger 13, D-85354 Freising (Germany); Reiter, I.M. [Ecophysiology of Plants, Department of Ecology, TU Muenchen, Am Hochanger 13, D-85354 Freising (Germany); Heerdt, C. [Bioclimatology, TU Muenchen, Am Hochanger 13, D-85354 Freising (Germany); Leuchner, M. [Bioclimatology, TU Muenchen, Am Hochanger 13, D-85354 Freising (Germany); Luetz, C. [Department of Physiology and Cell Physiology of Alpine Plants, University of Innsbruck, Sternwartestrasse 15, A-6020 Innsbruck (Austria); Liu, X. [Institute of Forest Botany and Tree Physiology, University of Freiburg, Georges-Koehler-Allee 53/54, D-79110 Freiburg (Germany); Low, M. [Ecophysiology of Plants, Department of Ecology, TU Muenchen, Am Hochanger 13, D-85354 Freising (Germany); Winkler, J.B. [GSF National Research Center for Environment and Health, Institute for Soil Ecology, Department of Environmental Engineering, Ingolstaedter Landstrasse 1, D-85764 Neuherberg (Germany); Grams, T.E.E. [Ecophysiology of Plants, Department of Ecology, TU Muenchen, Am Hochanger 13, D-85354 Freising (Germany); Haeberle, K.-H. [Ecophysiology of Plants, Department of Ecology, TU Muenchen, Am Hochanger 13, D-85354 Freising (Germany); Werner, H. [Bioclimatology, TU Muenchen, Am Hochanger 13, D-85354 Freising (Germany); Fabian, P. [Bioclimatology, TU Muenchen, Am Hochanger 13, D-85354 Freising (Germany); Rennenberg, H. [Departamento de Ecologia, Universidade de Brasilia, caixa postal 04457, Brasilia-DF 70919-970 (Brazil); Matyssek, R. [Ecophysiology of Plants, Department of Ecology, TU Muenchen, Am Hochanger 13, D-85354 Freising (Germany)

    2005-10-15

    Chamber experiments on juvenile trees have resulted in severe injury and accelerated loss of leaves along with reduced biomass production under chronically enhanced O{sub 3} levels. In contrast, the few studies conducted on adult forest trees in the field have reported low O{sub 3} sensitivity. In the present study, young beech in phytotrons was more sensitive to O{sub 3} than adult beech in the field, although employed O{sub 3} regimes were similar. The hypotheses tested were that: (1) differences in O{sub 3} uptake were caused by the ontogenetically higher stomatal conductance of young compared to adult trees (2) the experimental settings in the phytotrons enhanced O{sub 3} uptake compared to field conditions, and (3) a low detoxification capacity contributes to the higher O{sub 3} sensitivity of the young trees. The higher O{sub 3} sensitivity of juvenile beech in the phytotrons is demonstrated to relate to both the experimental conditions and the physiological responsiveness inherent to tree age. - Juvenile beech trees in phytotrons are more sensitive to ozone than adult forest trees due to lower defence capacity and growth conditions.

  15. Ozone production and its sensitivity to NOx and VOCs: results from the DISCOVER-AQ field experiment, Houston 2013

    Directory of Open Access Journals (Sweden)

    G. M. Mazzuca

    2016-11-01

    Full Text Available An observation-constrained box model based on the Carbon Bond mechanism, version 5 (CB05, was used to study photochemical processes along the NASA P-3B flight track and spirals over eight surface sites during the September 2013 Houston, Texas deployment of the NASA Deriving Information on Surface Conditions from COlumn and VERtically Resolved Observations Relevant to Air Quality (DISCOVER-AQ campaign. Data from this campaign provided an opportunity to examine and improve our understanding of atmospheric photochemical oxidation processes related to the formation of secondary air pollutants such as ozone (O3. O3 production and its sensitivity to NOx and volatile organic compounds (VOCs were calculated at different locations and times of day. Ozone production efficiency (OPE, defined as the ratio of the ozone production rate to the NOx oxidation rate, was calculated using the observations and the simulation results of the box and Community Multiscale Air Quality (CMAQ models. Correlations of these results with other parameters, such as radical sources and NOx mixing ratio, were also evaluated. It was generally found that O3 production tends to be more VOC-sensitive in the morning along with high ozone production rates, suggesting that control of VOCs may be an effective way to control O3 in Houston. In the afternoon, O3 production was found to be mainly NOx-sensitive with some exceptions. O3 production near major emissions sources such as Deer Park was mostly VOC-sensitive for the entire day, other urban areas near Moody Tower and Channelview were VOC-sensitive or in the transition regime, and areas farther from downtown Houston such as Smith Point and Conroe were mostly NOx-sensitive for the entire day. It was also found that the control of NOx emissions has reduced O3 concentrations over Houston but has led to larger OPE values. The results from this work strengthen our understanding of O3 production; they indicate that controlling NOx

  16. Does Posting Facebook Status Updates Increase or Decrease Loneliness? An Online Social Networking Experiment.

    Science.gov (United States)

    Deters, Fenne Große; Mehl, Matthias R

    2013-09-01

    Online social networking is a pervasive but empirically understudied phenomenon. Strong public opinions on its consequences exist but are backed up by little empirical evidence and almost no causally-conclusive, experimental research. The current study tested the psychological effects of posting status updates on Facebook using an experimental design. For one week, participants in the experimental condition were asked to post more than they usually do, whereas participants in the control condition received no instructions. Participants added a lab "Research Profile" as a Facebook friend allowing for the objective documentation of protocol compliance, participants' status updates, and friends' responses. Results revealed (1) that the experimentally-induced increase in status updating activity reduced loneliness, (2) that the decrease in loneliness was due to participants feeling more connected to their friends on a daily basis and (3) that the effect of posting on loneliness was independent of direct social feedback (i.e. responses) by friends.

  17. HIN3/396: Experience of Creation of the National (Regional) Telematics Medical Corporate Network in Ukraine

    Science.gov (United States)

    Mayorov, O; Ponomarenko, V; Kalnish, V

    1999-01-01

    Introduction Ukraine has an extensive experience on creating and maintaining National Medical Networks. A variety of examples include: The National Register of the persons suffered from the Chernobyl disaster: Net of the Sanitary and Epidemiological Service of the Ministry of Health. The National Medical Network for monitoring oncology patients: this links Regional Oncology Dispensaries with Institute of Oncology. Ukraine has a membership to "EuroTransplant" and National Medical Network in this effort has linked Regional Centres with the National Informational Centre on Transplantation. Regional databases from Regional Venereologic Dispensaries, used for monitoring diseases, have been extended to include cases of AIDS. The Telemedical Cardiology Centre in Kharkiv, with trans-telephone ECG. All equipment, including portable ECG amplifiers and modems, is developed in the Ukraine. Teleconsulting Medical Centres, in Kiev, for the analysis of MRI images. The centre "Patholog", in which oncologists - cytologists carry out work. The Ukrainian Association of Computer Medicine (UACM) has created (http: //www.uacm.cit-a.net) WWW- server , which has become a nucleus of the Corporate medical network permitting to exchange the information to 78 institutional members and over 900 individual members. The UACM has created affiliate Web - EHTO-UKRAINE server on national language (http://www.ehto-ukr.cit-ua.net). Ukraine took part in the "Telemedecine Medical Care Networks within the Baltic Region" programme. Also, Ukraine started the Ukrainian- American project on the monitoring of birth defects. Methods The National Telematics Medical Corporate Network 'UkrMedNet' is under construction on the basis of existing the HealthNet and some other autonomous medical networks, with the newest of telecommunication technologies, used in Internet. This project also envisages the integration of all existing separate medical nets, universities and R&D institutes into one 'UkrMedNet', as well as

  18. [Biomedical information networks: the experience of the United States National Library of Medicine].

    Science.gov (United States)

    Corning, M

    1981-01-01

    A rapid and intensive flow of biomedical information is perceived increasingly as a requirement for the advancement of research, professional training, and the delivery of health services to an ever-growing human population. This article examines the concept of a network of information and cooperative services among medical libraries and national, regional and international data banks to maximize the sharing and use of the available resources. The background and record of the National Library of Medicine of the United States, which established the MEDLARS System, are described as a model for guidance. Since the end of the 19th century, when J. S. Billings, the foresighted first director of the Library, devised the first system for the indexing of medical literature, new techniques have been introduced step by step to facilitate the dissemination of biomedical information: mechanization and automatization of the placement of requests and data retrieval, telecommunications and satellite links to the fifteen data banks currently accessible to the user by direct communication through MEDLINE. For such a network to operate successfully, there must be a shift from the idea of regional or national benefit to the plane of global cooperation, through which a higher degree of self-sufficiency can be achieved. Also, relations between the various levels of the system must be based on a collaboration in which each entity pursues its own function subject to the character and multifarious scope of the common purposes. The success of BIREME in Latin America is cited as an incentive to developing countries to participate in the use and distribution of vital information through activities based on individual priorities without forgetting that what is important is not ideals and abstractions, but the human being with his needs, problems and real situation.

  19. Strengthening Nepal's Female Community Health Volunteer network: a qualitative study of experiences at two years.

    Science.gov (United States)

    Schwarz, Dan; Sharma, Ranju; Bashyal, Chhitij; Schwarz, Ryan; Baruwal, Ashma; Karelas, Gregory; Basnet, Bibhusan; Khadka, Nirajan; Brady, Jesse; Silver, Zach; Mukherjee, Joia; Andrews, Jason; Maru, Duncan Smith-Rohrberg

    2014-10-09

    Nepal's Female Community Health Volunteer (FCHV) program has been described as an exemplary public-sector community health worker program. However, despite its merits, the program still struggles to provide high-quality, accessible services nation-wide. Both in Nepal and globally, best practices for community health worker program implementation are not yet known: there is a dearth of empiric research, and the research that has been done has shown inconsistent results. Here we evaluate a pilot program designed to strengthen the Nepali government's FCHV network. The program was structured with five core components: 1) improve local FCHV leadership; 2) facilitate structured weekly FCHV meetings and 3) weekly FCHV trainings at the village level; 4) implement a monitoring and evaluation system for FCHV patient encounters; and 5) provide financial compensation for FCHV work. Following twenty-four months of program implementation, a retrospective programmatic evaluation was conducted, including qualitative analysis of focus group discussions and semi-structured interviews. Qualitative data analysis demonstrated that the program was well-received by program participants and community members, and suggests that the five core components of this program were valuable additions to the pre-existing FCHV network. Analysis also revealed key challenges to program implementation including geographic limitations, literacy limitations, and limitations of professional respect from healthcare workers to FCHVs. Descriptive statistics are presented for programmatic process metrics and costs throughout the first twenty four months of implementation. The five components of this pilot program were well-received as a mechanism for strengthening Nepal's FCHV program. To our knowledge, this is the first study to present such data, specifically informing programmatic design and management of the FCHV program. Despite limitations in its scope, this study offers tangible steps forward for

  20. Forecast Surface Quality of Abrasive Water Jet Cutting Based on Neural Network and Verified by Experiments

    National Research Council Canada - National Science Library

    Gui-Lin Yang

    2013-01-01

      In this study, firstly, the YL12 aluminum alloy is used as experimental materials, then in the following experiments it is cut in JJ-I-type water jet machines, and 1,000 group data are gotten by measurement...