Science.gov

Sample records for impact information diffusion

  1. Information Technology Diffusion: Impact on Student Achievement

    ERIC Educational Resources Information Center

    Lee, Gregory M.; Lind, Mary L.

    2011-01-01

    For student achievement, the diffusion and adoption of information technology (IT) infrastructure enabled by special funding was posited to have a positive impact on student achievement. Four urban school districts provided the context for this study to assess the impact of IT adoption on standardized test scores.

  2. Impact of human activity patterns on the dynamics of information diffusion.

    PubMed

    Iribarren, José Luis; Moro, Esteban

    2009-07-17

    We study the impact of human activity patterns on information diffusion. To this end we ran a viral email experiment involving 31,183 individuals in which we were able to track a specific piece of information through the social network. We found that, contrary to traditional models, information travels at an unexpectedly slow pace. By using a branching model which accurately describes the experiment, we show that the large heterogeneity found in the response time is responsible for the slow dynamics of information at the collective level. Given the generality of our result, we discuss the important implications of this finding while modeling human dynamical collective phenomena.

  3. Optimal Network Modularity for Information Diffusion

    NASA Astrophysics Data System (ADS)

    Nematzadeh, Azadeh; Ferrara, Emilio; Flammini, Alessandro; Ahn, Yong-Yeol

    2014-08-01

    We investigate the impact of community structure on information diffusion with the linear threshold model. Our results demonstrate that modular structure may have counterintuitive effects on information diffusion when social reinforcement is present. We show that strong communities can facilitate global diffusion by enhancing local, intracommunity spreading. Using both analytic approaches and numerical simulations, we demonstrate the existence of an optimal network modularity, where global diffusion requires the minimal number of early adopters.

  4. Information filtering via preferential diffusion

    NASA Astrophysics Data System (ADS)

    Lü, Linyuan; Liu, Weiping

    2011-06-01

    Recommender systems have shown great potential in addressing the information overload problem, namely helping users in finding interesting and relevant objects within a huge information space. Some physical dynamics, including the heat conduction process and mass or energy diffusion on networks, have recently found applications in personalized recommendation. Most of the previous studies focus overwhelmingly on recommendation accuracy as the only important factor, while overlooking the significance of diversity and novelty that indeed provide the vitality of the system. In this paper, we propose a recommendation algorithm based on the preferential diffusion process on a user-object bipartite network. Numerical analyses on two benchmark data sets, MovieLens and Netflix, indicate that our method outperforms the state-of-the-art methods. Specifically, it can not only provide more accurate recommendations, but also generate more diverse and novel recommendations by accurately recommending unpopular objects.

  5. Information filtering via preferential diffusion.

    PubMed

    Lü, Linyuan; Liu, Weiping

    2011-06-01

    Recommender systems have shown great potential in addressing the information overload problem, namely helping users in finding interesting and relevant objects within a huge information space. Some physical dynamics, including the heat conduction process and mass or energy diffusion on networks, have recently found applications in personalized recommendation. Most of the previous studies focus overwhelmingly on recommendation accuracy as the only important factor, while overlooking the significance of diversity and novelty that indeed provide the vitality of the system. In this paper, we propose a recommendation algorithm based on the preferential diffusion process on a user-object bipartite network. Numerical analyses on two benchmark data sets, MovieLens and Netflix, indicate that our method outperforms the state-of-the-art methods. Specifically, it can not only provide more accurate recommendations, but also generate more diverse and novel recommendations by accurately recommending unpopular objects.

  6. Optimal multi-community network modularity for information diffusion

    NASA Astrophysics Data System (ADS)

    Wu, Jiaocan; Du, Ruping; Zheng, Yingying; Liu, Dong

    2016-02-01

    Studies demonstrate that community structure plays an important role in information spreading recently. In this paper, we investigate the impact of multi-community structure on information diffusion with linear threshold model. We utilize extended GN network that contains four communities and analyze dynamic behaviors of information that spreads on it. And we discover the optimal multi-community network modularity for information diffusion based on the social reinforcement. Results show that, within the appropriate range, multi-community structure will facilitate information diffusion instead of hindering it, which accords with the results derived from two-community network.

  7. Dynamics of information diffusion and its applications on complex networks

    NASA Astrophysics Data System (ADS)

    Zhang, Zi-Ke; Liu, Chuang; Zhan, Xiu-Xiu; Lu, Xin; Zhang, Chu-Xu; Zhang, Yi-Cheng

    2016-09-01

    The ongoing rapid expansion of the Word Wide Web (WWW) greatly increases the information of effective transmission from heterogeneous individuals to various systems. Extensive research for information diffusion is introduced by a broad range of communities including social and computer scientists, physicists, and interdisciplinary researchers. Despite substantial theoretical and empirical studies, unification and comparison of different theories and approaches are lacking, which impedes further advances. In this article, we review recent developments in information diffusion and discuss the major challenges. We compare and evaluate available models and algorithms to respectively investigate their physical roles and optimization designs. Potential impacts and future directions are discussed. We emphasize that information diffusion has great scientific depth and combines diverse research fields which makes it interesting for physicists as well as interdisciplinary researchers.

  8. Information Diffusion in Facebook-Like Social Networks Under Information Overload

    NASA Astrophysics Data System (ADS)

    Li, Pei; Xing, Kai; Wang, Dapeng; Zhang, Xin; Wang, Hui

    2013-07-01

    Research on social networks has received remarkable attention, since many people use social networks to broadcast information and stay connected with their friends. However, due to the information overload in social networks, it becomes increasingly difficult for users to find useful information. This paper takes Facebook-like social networks into account, and models the process of information diffusion under information overload. The term view scope is introduced to model the user information-processing capability under information overload, and the average number of times a message appears in view scopes after it is generated is proposed to characterize the information diffusion efficiency. Through theoretical analysis, we find that factors such as network structure and view scope number have no impact on the information diffusion efficiency, which is a surprising result. To verify the results, we conduct simulations and provide the simulation results, which are consistent with the theoretical analysis results perfectly.

  9. Influence Function Learning in Information Diffusion Networks

    PubMed Central

    Du, Nan; Liang, Yingyu; Balcan, Maria-Florina; Song, Le

    2015-01-01

    Can we learn the influence of a set of people in a social network from cascades of information diffusion? This question is often addressed by a two-stage approach: first learn a diffusion model, and then calculate the influence based on the learned model. Thus, the success of this approach relies heavily on the correctness of the diffusion model which is hard to verify for real world data. In this paper, we exploit the insight that the influence functions in many diffusion models are coverage functions, and propose a novel parameterization of such functions using a convex combination of random basis functions. Moreover, we propose an efficient maximum likelihood based algorithm to learn such functions directly from cascade data, and hence bypass the need to specify a particular diffusion model in advance. We provide both theoretical and empirical analysis for our approach, showing that the proposed approach can provably learn the influence function with low sample complexity, be robust to the unknown diffusion models, and significantly outperform existing approaches in both synthetic and real world data. PMID:25973445

  10. Exploiting Information Diffusion Feature for Link Prediction in Sina Weibo

    NASA Astrophysics Data System (ADS)

    Li, Dong; Zhang, Yongchao; Xu, Zhiming; Chu, Dianhui; Li, Sheng

    2016-01-01

    The rapid development of online social networks (e.g., Twitter and Facebook) has promoted research related to social networks in which link prediction is a key problem. Although numerous attempts have been made for link prediction based on network structure, node attribute and so on, few of the current studies have considered the impact of information diffusion on link creation and prediction. This paper mainly addresses Sina Weibo, which is the largest microblog platform with Chinese characteristics, and proposes the hypothesis that information diffusion influences link creation and verifies the hypothesis based on real data analysis. We also detect an important feature from the information diffusion process, which is used to promote link prediction performance. Finally, the experimental results on Sina Weibo dataset have demonstrated the effectiveness of our methods.

  11. Information diffusion in structured online social networks

    NASA Astrophysics Data System (ADS)

    Li, Pei; Zhang, Yini; Qiao, Fengcai; Wang, Hui

    2015-05-01

    Nowadays, due to the word-of-mouth effect, online social networks have been considered to be efficient approaches to conduct viral marketing, which makes it of great importance to understand the diffusion dynamics in online social networks. However, most research on diffusion dynamics in epidemiology and existing social networks cannot be applied directly to characterize online social networks. In this paper, we propose models to characterize the information diffusion in structured online social networks with push-based forwarding mechanism. We introduce the term user influence to characterize the average number of times that messages are browsed which is incurred by a given type user generating a message, and study the diffusion threshold, above which the user influence of generating a message will approach infinity. We conduct simulations and provide the simulation results, which are consistent with the theoretical analysis results perfectly. These results are of use in understanding the diffusion dynamics in online social networks and also critical for advertisers in viral marketing who want to estimate the user influence before posting an advertisement.

  12. Promoting information diffusion through interlayer recovery processes in multiplex networks

    NASA Astrophysics Data System (ADS)

    Wang, Xin; Li, Weihua; Liu, Longzhao; Pei, Sen; Tang, Shaoting; Zheng, Zhiming

    2017-09-01

    For information diffusion in multiplex networks, the effect of interlayer contagion on spreading dynamics has been explored in different settings. Nevertheless, the impact of interlayer recovery processes, i.e., the transition of nodes to stiflers in all layers after they become stiflers in any layer, still remains unclear. In this paper, we propose a modified ignorant-spreader-stifler model of rumor spreading equipped with an interlayer recovery mechanism. We find that the information diffusion can be effectively promoted for a range of interlayer recovery rates. By combining the mean-field approximation and the Markov chain approach, we derive the evolution equations of the diffusion process in two-layer homogeneous multiplex networks. The optimal interlayer recovery rate that achieves the maximal enhancement can be calculated by solving the equations numerically. In addition, we find that the promoting effect on a certain layer can be strengthened if information spreads more extensively within the counterpart layer. When applying the model to two-layer scale-free multiplex networks, with or without degree correlation, similar promoting effect is also observed in simulations. Our work indicates that the interlayer recovery process is beneficial to information diffusion in multiplex networks, which may have implications for designing efficient spreading strategies.

  13. SHIR competitive information diffusion model for online social media

    NASA Astrophysics Data System (ADS)

    Liu, Yun; Diao, Su-Meng; Zhu, Yi-Xiang; Liu, Qing

    2016-11-01

    In online social media, opinion divergences and differentiations generally exist as a result of individuals' extensive participation and personalization. In this paper, a Susceptible-Hesitated-Infected-Removed (SHIR) model is proposed to study the dynamics of competitive dual information diffusion. The proposed model extends the classical SIR model by adding hesitators as a neutralized state of dual information competition. It is both hesitators and stable spreaders that facilitate information dissemination. Researching on the impacts of diffusion parameters, it is found that the final density of stiflers increases monotonically as infection rate increases and removal rate decreases. And the advantage information with larger stable transition rate takes control of whole influence of dual information. The density of disadvantage information spreaders slightly grows with the increase of its stable transition rate, while whole spreaders of dual information and the relaxation time remain almost unchanged. Moreover, simulations imply that the final result of competition is closely related to the ratio of stable transition rates of dual information. If the stable transition rates of dual information are nearly the same, a slightly reduction of the smaller one brings out a significant disadvantage in its propagation coverage. Additionally, the relationship of the ratio of final stiflers versus the ratio of stable transition rates presents power characteristic.

  14. Monitoring Diffuse Impacts: Australian Tourism Developments.

    PubMed

    Warnken; Buckley

    2000-04-01

    / The scientific quality of monitoring for diffuse environmental impacts has rarely been quantified. This paper presents an analysis of all formal environmental monitoring programs for Australian tourism developments over a 15-year period from 1980 to 1995. The tourism sector provides a good test bed for this study because tourism developments are (1) often adjacent to or even within conservation reserves and other relatively undisturbed natural environments, and (2) often clustered, with resulting cumulative impacts that require detection at an early stage. Here we analyze the precision and reliability with which monitoring programs as actually implemented can detect diffuse environmental impacts against natural variation. Of 175 Australian tourism developments subject to EIA from 1980 to 1993 inclusive, only 13 were subject to formal monitoring. Only 44 individual parameters, in total, were monitored for all these developments together. No baseline monitoring was conducted for nine of the 44 parameters. For the remaining 35, only one was monitored for a full year. Before, after, control, impact, paired sampling (BACIP) monitoring designs were used for 24 of the 44 parameters, and power analysis in 10. The scientific quality of monitoring was significantly better for developments subject to control by the Great Barrier Reef Marine Park Authority (GBRMPA). The key factor appears to be the way in which GBRMPA uses external referees and manages external consultants. The GBRMPA model merits wider adoption.

  15. Information theoretic regularization in diffuse optical tomography.

    PubMed

    Panagiotou, Christos; Somayajula, Sangeetha; Gibson, Adam P; Schweiger, Martin; Leahy, Richard M; Arridge, Simon R

    2009-05-01

    Diffuse optical tomography (DOT) retrieves the spatially distributed optical characteristics of a medium from external measurements. Recovering the parameters of interest involves solving a nonlinear and highly ill-posed inverse problem. This paper examines the possibility of regularizing DOT via the introduction of a priori information from alternative high-resolution anatomical modalities, using the information theory concepts of mutual information (MI) and joint entropy (JE). Such functionals evaluate the similarity between the reconstructed optical image and the prior image while bypassing the multimodality barrier manifested as the incommensurate relation between the gray value representations of corresponding anatomical features in the two modalities. By introducing structural information, we aim to improve the spatial resolution and quantitative accuracy of the solution. We provide a thorough explanation of the theory from an imaging perspective, accompanied by preliminary results using numerical simulations. In addition we compare the performance of MI and JE. Finally, we have adopted a method for fast marginal entropy evaluation and optimization by modifying the objective function and extending it to the JE case. We demonstrate its use on an image reconstruction framework and show significant computational savings.

  16. Information Technology Diffusion: A Comparative Case Study of Intranet Adoption

    DTIC Science & Technology

    1999-07-01

    Information Technology Diffusion: A Comparative Case Study of Intranet Adoption George A. Zolla Jr. Naval Postgraduate School, Monterey, CA 93943...unfreezing”. Cooper and Zmud [4] defined IT implementation as “an organizational effort directed toward diffusing appropriate information technology within a...1999 4. TITLE AND SUBTITLE Information Technology Diffusion: A Comparative Case Study of Intranet Adoption 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c

  17. Symmetrical and overloaded effect of diffusion in information filtering

    NASA Astrophysics Data System (ADS)

    Zhu, Xuzhen; Tian, Hui; Chen, Guilin; Cai, Shimin

    2017-10-01

    In physical dynamics, mass diffusion theory has been applied to design effective information filtering models on bipartite network. In previous works, researchers unilaterally believe objects' similarities are determined by single directional mass diffusion from the collected object to the uncollected, meanwhile, inadvertently ignore adverse influence of diffusion overload. It in some extent veils the essence of diffusion in physical dynamics and hurts the recommendation accuracy and diversity. After delicate investigation, we argue that symmetrical diffusion effectively discloses essence of mass diffusion, and high diffusion overload should be published. Accordingly, in this paper, we propose an symmetrical and overload penalized diffusion based model (SOPD), which shows excellent performances in extensive experiments on benchmark datasets Movielens and Netflix.

  18. Diffusion processes of fragmentary information on scale-free networks

    NASA Astrophysics Data System (ADS)

    Li, Xun; Cao, Lang

    2016-05-01

    Compartmental models of diffusion over contact networks have proven representative of real-life propagation phenomena among interacting individuals. However, there is a broad class of collective spreading mechanisms departing from compartmental representations, including those for diffusive objects capable of fragmentation and transmission unnecessarily as a whole. Here, we consider a continuous-state susceptible-infected-susceptible (SIS) model as an ideal limit-case of diffusion processes of fragmentary information on networks, where individuals possess fractions of the information content and update them by selectively exchanging messages with partners in the vicinity. Specifically, we incorporate local information, such as neighbors' node degrees and carried contents, into the individual partner choice, and examine the roles of a variety of such strategies in the information diffusion process, both qualitatively and quantitatively. Our method provides an effective and flexible route of modulating continuous-state diffusion dynamics on networks and has potential in a wide array of practical applications.

  19. Impacts of suppressing guide on information spreading

    NASA Astrophysics Data System (ADS)

    Xu, Jinghong; Zhang, Lin; Ma, Baojun; Wu, Ye

    2016-02-01

    It is quite common that guides are introduced to suppress the information spreading in modern society for different purposes. In this paper, an agent-based model is established to quantitatively analyze the impacts of suppressing guides on information spreading. We find that the spreading threshold depends on the attractiveness of the information and the topology of the social network with no suppressing guides at all. Usually, one would expect that the existence of suppressing guides in the spreading procedure may result in less diffusion of information within the overall network. However, we find that sometimes the opposite is true: the manipulating nodes of suppressing guides may lead to more extensive information spreading when there are audiences with the reversal mind. These results can provide valuable theoretical references to public opinion guidance on various information, e.g., rumor or news spreading.

  20. The electronic transfer of information and aerospace knowledge diffusion

    NASA Technical Reports Server (NTRS)

    Pinelli, Thomas E.; Bishop, Ann P.; Barclay, Rebecca O.; Kennedy, John M.

    1992-01-01

    Increasing reliance on and investment in information technology and electronic networking systems presupposes that computing and information technology will play a motor role in the diffusion of aerospace knowledge. Little is known, however, about actual information technology needs, uses, and problems within the aerospace knowledge diffusion process. The authors state that the potential contributions of information technology to increased productivity and competitiveness will be diminished unless empirically derived knowledge regarding the information-seeking behavior of the members of the social system - those who are producing, transferring, and using scientific and technical information - is incorporated into a new technology policy framework. Research into the use of information technology and electronic networks by U.S. aerospace engineers and scientists, collected as part of a research project designed to study aerospace knowledge diffusion, is presented in support of this assertion.

  1. Affinity based information diffusion model in social networks

    NASA Astrophysics Data System (ADS)

    Liu, Hongli; Xie, Yun; Hu, Haibo; Chen, Zhigao

    2014-12-01

    There is a widespread intuitive sense that people prefer participating in spreading the information in which they are interested. The affinity of people with information disseminated can affect the information propagation in social networks. In this paper, we propose an information diffusion model incorporating the mechanism of affinity of people with information which considers the fitness of affinity values of people with affinity threshold of the information. We find that the final size of information diffusion is affected by affinity threshold of the information, average degree of the network and the probability of people's losing their interest in the information. We also explore the effects of other factors on information spreading by numerical simulations and find that the probabilities of people's questioning and confirming the information can affect the propagation speed, but not the final scope.

  2. Correlation between information diffusion and opinion evolution on social media

    NASA Astrophysics Data System (ADS)

    Xiong, Fei; Liu, Yun; Zhang, Zhenjiang

    2014-12-01

    Information diffusion and opinion evolution are often treated as two independent processes. Opinion models assume the topic reaches each agent and agents initially have their own ideas. In fact, the processes of information diffusion and opinion evolution often intertwine with each other. Whether the influence between these two processes plays a role in the system state is unclear. In this paper, we collected more than one million real data from a well-known social platform, and analysed large-scale user diffusion behaviour and opinion formation. We found that user inter-event time follows a two-scaling power-law distribution with two different power exponents. Public opinion stabilizes quickly and evolves toward the direction of convergence, but the consensus state is prevented by a few opponents. We propose a three-state opinion model accompanied by information diffusion. Agents form and exchange their opinions during information diffusion. Conversely, agents' opinions also influence their diffusion actions. Simulations show that the model with a correlation of the two processes produces similar statistical characteristics as empirical results. A fast epidemic process drives individual opinions to converge more obviously. Unlike previous epidemic models, the number of infected agents does not always increase with the update rate, but has a peak with an intermediate value of the rate.

  3. Fluid Registration of Diffusion Tensor Images Using Information Theory

    PubMed Central

    Chiang, Ming-Chang; Leow, Alex D.; Klunder, Andrea D.; Dutton, Rebecca A.; Barysheva, Marina; Rose, Stephen E.; McMahon, Katie L.; de Zubicaray, Greig I.; Toga, Arthur W.; Thompson, Paul M.

    2008-01-01

    We apply an information-theoretic cost metric, the symmetrized Kullback-Leibler (sKL) divergence, or J-divergence, to fluid registration of diffusion tensor images. The difference between diffusion tensors is quantified based on the sKL-divergence of their associated probability density functions (PDFs). Three-dimensional DTI data from 34 subjects were fluidly registered to an optimized target image. To allow large image deformations but preserve image topology, we regularized the flow with a large-deformation diffeomorphic mapping based on the kinematics of a Navier-Stokes fluid. A driving force was developed to minimize the J-divergence between the deforming source and target diffusion functions, while reorienting the flowing tensors to preserve fiber topography. In initial experiments, we showed that the sKL-divergence based on full diffusion PDFs is adaptable to higher-order diffusion models, such as high angular resolution diffusion imaging (HARDI). The sKL-divergence was sensitive to subtle differences between two diffusivity profiles, showing promise for nonlinear registration applications and multisubject statistical analysis of HARDI data. PMID:18390342

  4. Discovery of Information Diffusion Process in Social Networks

    NASA Astrophysics Data System (ADS)

    Kim, Kwanho; Jung, Jae-Yoon; Park, Jonghun

    Information diffusion analysis in social networks is of significance since it enables us to deeply understand dynamic social interactions among users. In this paper, we introduce approaches to discovering information diffusion process in social networks based on process mining. Process mining techniques are applied from three perspectives: social network analysis, process discovery and community recognition. We then present experimental results by using a real-life social network data. The proposed techniques are expected to employ as new analytical tools in online social networks such as blog and wikis for company marketers, politicians, news reporters and online writers.

  5. Intensive Care Information System Impacts

    PubMed Central

    Ehteshami, Asghar; Sadoughi, Farahnaz; Ahmadi, Maryam; Kashefi, Parviz

    2013-01-01

    Introduction: Today, intensive care needs to be increased with a prospect of an aging population and socioeconomic factors influencing health intervention, but there are some problems in the intensive care environments, it is essential to resolve. The intensive Care information system has the potential to solve many of ICU problems. The objective of the review was to establish the impact of intensive care information systems on the practitioners practice, patient outcomes and ICU performance. Methods: Scientific databases and electronic journal citations was searched to identify articles that discussed the impacts of intensive care information system on the practices, patient outcomes and ICU performance. A total of 22 articles discussing ICIS outcomes was included in this study from 609 articles initially obtained from the searches. Results: Pooling data across studies, we found that the median impact of ICIS on information management was 48.7%. The median impact of ICIS on user’ outcomes was 36.4%, impact on saving tips by 24%, clinical decision support by a mean of 22.7%, clinical outcomes improved by a mean of 18.6%, and researches improved by 18%. Conclusion: The functionalities of ICIS are growing day by day and new functionalities are available with every major release. Better adoption of ICIS by the intensive care environments emphasizes the opportunity of better intensive care services through patient oriented intensive care clinical information systems. There is an immense need for developing guidelines for standardizing ICIS to to maximize the power of ICISs and to integrate with HISs. This will enable intensivists to use the systems in a more meaningful way for better patient care. This study provides a better understanding and greater insight into the effectiveness of ICIS in improving patient care and reducing health care expenses. PMID:24167389

  6. Extracting spatial information from large aperture exposures of diffuse sources

    NASA Technical Reports Server (NTRS)

    Clarke, J. T.; Moos, H. W.

    1981-01-01

    The spatial properties of large aperture exposures of diffuse emission can be used both to investigate spatial variations in the emission and to filter out camera noise in exposures of weak emission sources. Spatial imaging can be accomplished both parallel and perpendicular to dispersion with a resolution of 5-6 arc sec, and a narrow median filter running perpendicular to dispersion across a diffuse image selectively filters out point source features, such as reseaux marks and fast particle hits. Spatial information derived from observations of solar system objects is presented.

  7. Phase transitions for information diffusion in random clustered networks

    NASA Astrophysics Data System (ADS)

    Lim, Sungsu; Shin, Joongbo; Kwak, Namju; Jung, Kyomin

    2016-09-01

    We study the conditions for the phase transitions of information diffusion in complex networks. Using the random clustered network model, a generalisation of the Chung-Lu random network model incorporating clustering, we examine the effect of clustering under the Susceptible-Infected-Recovered (SIR) epidemic diffusion model with heterogeneous contact rates. For this purpose, we exploit the branching process to analyse information diffusion in random unclustered networks with arbitrary contact rates, and provide novel iterative algorithms for estimating the conditions and sizes of global cascades, respectively. Showing that a random clustered network can be mapped into a factor graph, which is a locally tree-like structure, we successfully extend our analysis to random clustered networks with heterogeneous contact rates. We then identify the conditions for phase transitions of information diffusion using our method. Interestingly, for various contact rates, we prove that random clustered networks with higher clustering coefficients have strictly lower phase transition points for any given degree sequence. Finally, we confirm our analytical results with numerical simulations of both synthetically-generated and real-world networks.

  8. Impact of measurement parameters on apparent diffusion coefficient quantification in diffusion-weighted-magnetic resonance imaging.

    PubMed

    Schmidt, Holger; Gatidis, Sergios; Schwenzer, Nina F; Martirosian, Petros

    2015-01-01

    The scope of this work was to systematically evaluate the reproducibility of diffusion-weighted imaging and the impact of b values used for apparent diffusion coefficient (ADC) calculation as well as the echo time (TE) on the resulting ADC in phantom studies. We attempted to find a minimum upper b value needed for reliable ADC measurements. In addition, we were able to investigate these impacts not only for different diffusivities but also for different T2 relaxation times. The influence of different b values on ADC calculations for different organs was also assessed in a volunteer study. Diffusion-weighted imaging of a phantom consisting of 16 compartments with combinations of 4 different diffusivities and 4 different T2 relaxation times was conducted 5 times using 11 b values (0-1000 s/mm) and 5 different TEs. Apparent diffusion coefficient was calculated from the 16 compartment regions of interest using 42 different combinations of b values. Reproducibility of ADC was assessed from the coefficient of variation of the 5 measurements. The ADC stability was determined from a voxel-based coefficient of variation (CVsta) and the signal-to-noise ratio (SNR) to find the minimum upper b values for a reliable ADC quantification. The influence of TE on ADC quantification was assessed for 9 different b value combinations. The influence of 9 different b value combinations on ADC was evaluated by a region of interest analysis of 7 organs in 12 volunteers. The found coefficient of variation was between 10.2% and 1.4%, decreasing with increasing upper b value and increasing diffusivities. Accordingly, CVsta and SNR showed the same trend. Using an upper b value of 600 s/mm gives already reliable ADC results showing a maximum CVsta of 7.5%, whereas an upper b value of 1000 s/mm revealed a maximum CVsta of 5.5%. Values of ADC reduced with increasing upper b value in phantom as well as in human data. Apparent diffusion coefficient also reduced with increasing TE and tended to

  9. Information Technology Diffusion in Academic Teaching: An Institutional Perspective

    NASA Astrophysics Data System (ADS)

    Naveh, Gali; Tubin, Dorit; Pliskin, Nava

    Even though diffusion of information and communication technology (ICT) in academic teaching has been fast, the expected benefits in pedagogy and structure have yet to materialize. Rogers' diffusion theory, which focuses on adoption and rejection of innovation, can explain the proliferation of ICT usage in academia, but the lack of ICT-based pedagogical and structural changes are beyond the scope of diffusion theory. The objective of this paper is to broaden the theoretical base for explaining the state of ICT in academia via the alternative conceptual lens of institutional theory, which focuses on the relationship between the organization and its environment. With the institutional theory perspective in mind, we suggest that further pedagogical and structural changes in academic courses should not be expected as a result of ICT implementation in academic teaching.

  10. The Diffusion of Research on the Adoption and Diffusion of Information Technology

    NASA Astrophysics Data System (ADS)

    Dwivedi, Yogesh K.; Williams, Michael D.; Lal, Banita

    The considerable level of investigation into information systems and technology acceptance and diffusion to date has witnessed the use of an extensive range of exploratory techniques examining numerous diverse systems and technologies in a myriad of different contexts. The aim of this paper is to provide a comprehensive and systematic review of the literature relating to such adoption and diffusion issues in order to establish the current "state of play" in the domain along a number of dimensions including unit of analysis, research paradigm employed, technology examined, and theoretical models and constructs. Our findings suggest that the positivist paradigm, empirical and quantitative research, the survey method, and TAM theory were used predominantly when investigating the topics of adoption and diffusion of technology. Although the adoption of broad range of technologies has been examined, our results indicate that a number of technologies have so far received relatively little investigative attention.

  11. Impact of diffusion on surface clustering in random hydrodynamic flows

    NASA Astrophysics Data System (ADS)

    Klyatskin, V. I.; Koshel, K. V.

    2017-01-01

    Buoyant material clustering in a stochastic flow, which is homogeneous and isotropic in space and stationary in time, is addressed. The dynamics of buoyant material in three-dimensional hydrodynamic flows can be considered as the motion of passive tracers in a compressible two-dimensional velocity field. The latter is of interest in the present study. It is well known that the clustering of the density of passive tracers occurs in this case. We evaluate the impact of diffusion on the clustering process by using a numerical model. In general, the effect of diffusion is negligible in the very beginning of the evolution of initially uniformly distributed passive tracers. Therefore, the clustering of the density of passive tracers can emerge in accordance with the general theory. We analyze the long time clustering affected by diffusion and show that the emerged cluster structure persists in time in spite of the diffusion effect. However, the clusters split in time.

  12. Maximizing Information Diffusion in the Cyber-physical Integrated Network.

    PubMed

    Lu, Hongliang; Lv, Shaohe; Jiao, Xianlong; Wang, Xiaodong; Liu, Juan

    2015-11-11

    Nowadays, our living environment has been embedded with smart objects, such as smart sensors, smart watches and smart phones. They make cyberspace and physical space integrated by their abundant abilities of sensing, communication and computation, forming a cyber-physical integrated network. In order to maximize information diffusion in such a network, a group of objects are selected as the forwarding points. To optimize the selection, a minimum connected dominating set (CDS) strategy is adopted. However, existing approaches focus on minimizing the size of the CDS, neglecting an important factor: the weight of links. In this paper, we propose a distributed maximizing the probability of information diffusion (DMPID) algorithm in the cyber-physical integrated network. Unlike previous approaches that only consider the size of CDS selection, DMPID also considers the information spread probability that depends on the weight of links. To weaken the effects of excessively-weighted links, we also present an optimization strategy that can properly balance the two factors. The results of extensive simulation show that DMPID can nearly double the information diffusion probability, while keeping a reasonable size of selection with low overhead in different distributed networks.

  13. Information Filtering via Heterogeneous Diffusion in Online Bipartite Networks

    PubMed Central

    Zhang, Fu-Guo; Zeng, An

    2015-01-01

    The rapid expansion of Internet brings us overwhelming online information, which is impossible for an individual to go through all of it. Therefore, recommender systems were created to help people dig through this abundance of information. In networks composed by users and objects, recommender algorithms based on diffusion have been proven to be one of the best performing methods. Previous works considered the diffusion process from user to object, and from object to user to be equivalent. We show in this work that it is not the case and we improve the quality of the recommendation by taking into account the asymmetrical nature of this process. We apply this idea to modify the state-of-the-art recommendation methods. The simulation results show that the new methods can outperform these existing methods in both recommendation accuracy and diversity. Finally, this modification is checked to be able to improve the recommendation in a realistic case. PMID:26125631

  14. Social Information Transmission in Animals: Lessons from Studies of Diffusion

    PubMed Central

    Duboscq, Julie; Romano, Valéria; MacIntosh, Andrew; Sueur, Cédric

    2016-01-01

    The capacity to use information provided by others to guide behavior is a widespread phenomenon in animal societies. A standard paradigm to test if and/or how animals use and transfer social information is through social diffusion experiments, by which researchers observe how information spreads within a group, sometimes by seeding new behavior in the population. In this article, we review the context, methodology and products of such social diffusion experiments. Our major focus is the transmission of information from an individual (or group thereof) to another, and the factors that can enhance or, more interestingly, inhibit it. We therefore also discuss reasons why social transmission sometimes does not occur despite being expected to. We span a full range of mechanisms and processes, from the nature of social information itself and the cognitive abilities of various species, to the idea of social competency and the constraints imposed by the social networks in which animals are embedded. We ultimately aim at a broad reflection on practical and theoretical issues arising when studying how social information spreads within animal groups. PMID:27540368

  15. Social Information Transmission in Animals: Lessons from Studies of Diffusion.

    PubMed

    Duboscq, Julie; Romano, Valéria; MacIntosh, Andrew; Sueur, Cédric

    2016-01-01

    The capacity to use information provided by others to guide behavior is a widespread phenomenon in animal societies. A standard paradigm to test if and/or how animals use and transfer social information is through social diffusion experiments, by which researchers observe how information spreads within a group, sometimes by seeding new behavior in the population. In this article, we review the context, methodology and products of such social diffusion experiments. Our major focus is the transmission of information from an individual (or group thereof) to another, and the factors that can enhance or, more interestingly, inhibit it. We therefore also discuss reasons why social transmission sometimes does not occur despite being expected to. We span a full range of mechanisms and processes, from the nature of social information itself and the cognitive abilities of various species, to the idea of social competency and the constraints imposed by the social networks in which animals are embedded. We ultimately aim at a broad reflection on practical and theoretical issues arising when studying how social information spreads within animal groups.

  16. SL9 Impacts and Simulations of Enhanced Radial Diffusion

    NASA Astrophysics Data System (ADS)

    de Pater, Imke; Brecht, Stephen H.

    2001-05-01

    We present detailed calculations on enhanced radial diffusion models and show that many, though not all, of the phenomena observed during the week that Comet Shoemaker-Levy 9 crashed into Jupiter can be explained by a sudden increase in the radial diffusion coefficient. Our calculations use estimates for the enhancement in the diffusion coefficient which come from self-consistent calculations of the electromagnetic turbulence generated by the impacts (Brecht et al. 2001, Icarus). These calculations suggest that the diffusion coefficient is enhanced at least a few million times above the nominal value during a short period of time (minutes). Our model shows that Jupiter's main radiation peaks brighten up much more than the high latitude regions, as is indeed observed following impacts during the first few days of the impact week. The calculations also suggest that the largest enhancements in intensity and largest inward shift of the radiation peaks occur at jovicentric longitudes ˜100°≲λ III≲250°, i.e., the longitude range where the B=constant contours are furthest from the planet. This longitude range agrees with the region where the strongest enhancements have indeed been observed. The dramatic increase in the intensity of the high latitude peaks following impacts which took place later in the week is attributed to a direct acceleration of electrons by the upward propagating shock. Finally, compared to the observations, the radial diffusion models predict much larger enhancements in the radiation peaks than observed. We attribute this, as well as the initial decrease in intensity on July 16-17, to a large loss of electrons caused by pitch angle scattering.

  17. Split operator method for fluorescence diffuse optical tomography using anisotropic diffusion regularisation with prior anatomical information

    PubMed Central

    Correia, Teresa; Aguirre, Juan; Sisniega, Alejandro; Chamorro-Servent, Judit; Abascal, Juan; Vaquero, Juan J.; Desco, Manuel; Kolehmainen, Ville; Arridge, Simon

    2011-01-01

    Fluorescence diffuse optical tomography (fDOT) is an imaging modality that provides images of the fluorochrome distribution within the object of study. The image reconstruction problem is ill-posed and highly underdetermined and, therefore, regularisation techniques need to be used. In this paper we use a nonlinear anisotropic diffusion regularisation term that incorporates anatomical prior information. We introduce a split operator method that reduces the nonlinear inverse problem to two simpler problems, allowing fast and efficient solution of the fDOT problem. We tested our method using simulated, phantom and ex-vivo mouse data, and found that it provides reconstructions with better spatial localisation and size of fluorochrome inclusions than using the standard Tikhonov penalty term. PMID:22091447

  18. The impact of network characteristics on the diffusion of innovations

    NASA Astrophysics Data System (ADS)

    Peres, Renana

    2014-05-01

    This paper studies the influence of network topology on the speed and reach of new product diffusion. While previous research has focused on comparing network types, this paper explores explicitly the relationship between topology and measurements of diffusion effectiveness. We study simultaneously the effect of three network metrics: the average degree, the relative degree of social hubs (i.e., the ratio of the average degree of highly-connected individuals to the average degree of the entire population), and the clustering coefficient. A novel network-generation procedure based on random graphs with a planted partition is used to generate 160 networks with a wide range of values for these topological metrics. Using an agent-based model, we simulate diffusion on these networks and check the dependence of the net present value (NPV) of the number of adopters over time on the network metrics. We find that the average degree and the relative degree of social hubs have a positive influence on diffusion. This result emphasizes the importance of high network connectivity and strong hubs. The clustering coefficient has a negative impact on diffusion, a finding that contributes to the ongoing controversy on the benefits and disadvantages of transitivity. These results hold for both monopolistic and duopolistic markets, and were also tested on a sample of 12 real networks.

  19. Suppressing disease spreading by using information diffusion on multiplex networks

    NASA Astrophysics Data System (ADS)

    Wang, Wei; Liu, Quan-Hui; Cai, Shi-Min; Tang, Ming; Braunstein, Lidia A.; Stanley, H. Eugene

    2016-07-01

    Although there is always an interplay between the dynamics of information diffusion and disease spreading, the empirical research on the systemic coevolution mechanisms connecting these two spreading dynamics is still lacking. Here we investigate the coevolution mechanisms and dynamics between information and disease spreading by utilizing real data and a proposed spreading model on multiplex network. Our empirical analysis finds asymmetrical interactions between the information and disease spreading dynamics. Our results obtained from both the theoretical framework and extensive stochastic numerical simulations suggest that an information outbreak can be triggered in a communication network by its own spreading dynamics or by a disease outbreak on a contact network, but that the disease threshold is not affected by information spreading. Our key finding is that there is an optimal information transmission rate that markedly suppresses the disease spreading. We find that the time evolution of the dynamics in the proposed model qualitatively agrees with the real-world spreading processes at the optimal information transmission rate.

  20. Information and disease diffusion in dynamic social environments

    NASA Astrophysics Data System (ADS)

    Vespignani, Alessandro

    2013-03-01

    In recent years the increasing availability of computer power and informatics tools has enabled the gathering of reliable data quantifying the complexity of socio-technical systems. Data-driven computational models have emerged as appropriate tools to tackle the study of contagion and diffusion processes as diverse as epidemic outbreaks, information spreading and Internet packet routing. These models aim at providing a rationale for understanding the emerging tipping points and nonlinear properties that often underpin the most interesting characteristics of socio-technical systems. Here I review some of the recent progress in modeling contagion and epidemic processes that integrates the complex features and heterogeneities of real-world systems.

  1. Diffused holographic information storage and retrieval using photorefractive optical materials

    NASA Astrophysics Data System (ADS)

    McMillen, Deanna Kay

    Holography offers a tremendous opportunity for dense information storage, theoretically one bit per cubic wavelength of material volume, with rapid retrieval, of up to thousands of pages of information simultaneously. However, many factors prevent the theoretical storage limit from being reached, including dynamic range problems and imperfections in recording materials. This research explores new ways of moving closer to practical holographic information storage and retrieval by altering the recording materials, in this case, photorefractive crystals, and by increasing the current storage capacity while improving the information retrieved. As an experimental example of the techniques developed, the information retrieved is the correlation peak from an optical recognition architecture, but the materials and methods developed are applicable to many other holographic information storage systems. Optical correlators can potentially solve any signal or image recognition problem. Military surveillance, fingerprint identification for law enforcement or employee identification, and video games are but a few examples of applications. A major obstacle keeping optical correlators from being universally accepted is the lack of a high quality, thick (high capacity) holographic recording material that operates with red or infrared wavelengths which are available from inexpensive diode lasers. This research addresses the problems from two positions: find a better material for use with diode lasers, and reduce the requirements placed on the material while maintaining an efficient and effective system. This research found that the solutions are new dopants introduced into photorefractive lithium niobate to improve wavelength sensitivities and the use of a novel inexpensive diffuser that reduces the dynamic range and optical element quality requirements (which reduces the cost) while improving performance. A uniquely doped set of 12 lithium niobate crystals was specified and

  2. Information loss and reconstruction in diffuse fluorescence tomography.

    PubMed

    Bonfert-Taylor, Petra; Leblond, Frederic; Holt, Robert W; Tichauer, Kenneth; Pogue, Brian W; Taylor, Edward C

    2012-03-01

    This paper is a theoretical exploration of spatial resolution in diffuse fluorescence tomography. It is demonstrated that, given a fixed imaging geometry, one cannot-relative to standard techniques such as Tikhonov regularization and truncated singular value decomposition-improve the spatial resolution of the optical reconstructions via increasing the node density of the mesh considered for modeling light transport. Using techniques from linear algebra, it is shown that, as one increases the number of nodes beyond the number of measurements, information is lost by the forward model. It is demonstrated that this information cannot be recovered using various common reconstruction techniques. Evidence is provided showing that this phenomenon is related to the smoothing properties of the elliptic forward model that is used in the diffusion approximation to light transport in tissue. This argues for reconstruction techniques that are sensitive to boundaries, such as L1-reconstruction and the use of priors, as well as the natural approach of building a measurement geometry that reflects the desired image resolution.

  3. Information loss and reconstruction in diffuse fluorescence tomography

    PubMed Central

    Bonfert-Taylor, Petra; Leblond, Frederic; Holt, Robert W.; Tichauer, Kenneth; Pogue, Brian W.; Taylor, Edward C.

    2012-01-01

    This paper is a theoretical exploration of spatial resolution in diffuse fluorescence tomography. It is demonstrated that, given a fixed imaging geometry, one cannot—relative to standard techniques such as Tikhonov regularization and truncated singular value decomposition—improve the spatial resolution of the optical reconstructions via increasing the node density of the mesh considered for modeling light transport. Using techniques from linear algebra, it is shown that, as one increases the number of nodes beyond the number of measurements, information is lost by the forward model. It is demonstrated that this information cannot be recovered using various common reconstruction techniques. Evidence is provided showing that this phenomenon is related to the smoothing properties of the elliptic forward model that is used in the diffusion approximation to light transport in tissue. This argues for reconstruction techniques that are sensitive to boundaries, such as L1-reconstruction and the use of priors, as well as the natural approach of building a measurement geometry that reflects the desired image resolution. PMID:22472763

  4. Mechanical vs. informational components of price impact

    NASA Astrophysics Data System (ADS)

    Doyne Farmer, J.; Zamani, N.

    2007-01-01

    We study the problem of what causes prices to change. It is well known that trading impacts prices — orders to buy drive the price up, and orders to sell drive it down. We introduce a means of decomposing the total impact of trading into two components, defining the mechanical impact of a trading order as the change in future prices in the absence of any future changes in decision making, and the informational impact as the remainder of the total impact once mechanical impact is removed. This decomposition is performed using order book data from the London Stock Exchange. The average mechanical impact of a market order decays to zero as a function of time, at an asymptotic rate that is consistent with a power law with an exponent of roughly 1.7. In contrast the average informational impact builds to approach a constant value. Initially the impact is entirely mechanical, and is about half as big as the asymptotic informational impact. The size of the informational impact is positively correlated to mechanical impact. For cases where the mechanical impact is zero for all times, we find that the informational impact is negative, i.e. buy market orders that have no mechanical impact at all generate strong negative price responses.

  5. Modeling of Information Diffusion in Twitter-Like Social Networks under Information Overload

    PubMed Central

    Li, Wei

    2014-01-01

    Due to the existence of information overload in social networks, it becomes increasingly difficult for users to find useful information according to their interests. This paper takes Twitter-like social networks into account and proposes models to characterize the process of information diffusion under information overload. Users are classified into different types according to their in-degrees and out-degrees, and user behaviors are generalized into two categories: generating and forwarding. View scope is introduced to model the user information-processing capability under information overload, and the average number of times a message appears in view scopes after it is generated by a given type user is adopted to characterize the information diffusion efficiency, which is calculated theoretically. To verify the accuracy of theoretical analysis results, we conduct simulations and provide the simulation results, which are consistent with the theoretical analysis results perfectly. These results are of importance to understand the diffusion dynamics in social networks, and this analysis framework can be extended to consider more realistic situations. PMID:24795541

  6. Modeling of information diffusion in Twitter-like social networks under information overload.

    PubMed

    Li, Pei; Li, Wei; Wang, Hui; Zhang, Xin

    2014-01-01

    Due to the existence of information overload in social networks, it becomes increasingly difficult for users to find useful information according to their interests. This paper takes Twitter-like social networks into account and proposes models to characterize the process of information diffusion under information overload. Users are classified into different types according to their in-degrees and out-degrees, and user behaviors are generalized into two categories: generating and forwarding. View scope is introduced to model the user information-processing capability under information overload, and the average number of times a message appears in view scopes after it is generated by a given type user is adopted to characterize the information diffusion efficiency, which is calculated theoretically. To verify the accuracy of theoretical analysis results, we conduct simulations and provide the simulation results, which are consistent with the theoretical analysis results perfectly. These results are of importance to understand the diffusion dynamics in social networks, and this analysis framework can be extended to consider more realistic situations.

  7. A diffusive information preservation method for small Knudsen number flows

    SciTech Connect

    Fei, Fei; Fan, Jing

    2013-06-15

    The direct simulation Monte Carlo (DSMC) method is a powerful particle-based method for modeling gas flows. It works well for relatively large Knudsen (Kn) numbers, typically larger than 0.01, but quickly becomes computationally intensive as Kn decreases due to its time step and cell size limitations. An alternative approach was proposed to relax or remove these limitations, based on replacing pairwise collisions with a stochastic model corresponding to the Fokker–Planck equation [J. Comput. Phys., 229, 1077 (2010); J. Fluid Mech., 680, 574 (2011)]. Similar to the DSMC method, the downside of that approach suffers from computationally statistical noise. To solve the problem, a diffusion-based information preservation (D-IP) method has been developed. The main idea is to track the motion of a simulated molecule from the diffusive standpoint, and obtain the flow velocity and temperature through sampling and averaging the IP quantities. To validate the idea and the corresponding model, several benchmark problems with Kn ∼ 10{sup −3}–10{sup −4} have been investigated. It is shown that the IP calculations are not only accurate, but also efficient because they make possible using a time step and cell size over an order of magnitude larger than the mean collision time and mean free path, respectively.

  8. A diffusive information preservation method for small Knudsen number flows

    NASA Astrophysics Data System (ADS)

    Fei, Fei; Fan, Jing

    2013-06-01

    The direct simulation Monte Carlo (DSMC) method is a powerful particle-based method for modeling gas flows. It works well for relatively large Knudsen (Kn) numbers, typically larger than 0.01, but quickly becomes computationally intensive as Kn decreases due to its time step and cell size limitations. An alternative approach was proposed to relax or remove these limitations, based on replacing pairwise collisions with a stochastic model corresponding to the Fokker-Planck equation [J. Comput. Phys., 229, 1077 (2010); J. Fluid Mech., 680, 574 (2011)]. Similar to the DSMC method, the downside of that approach suffers from computationally statistical noise. To solve the problem, a diffusion-based information preservation (D-IP) method has been developed. The main idea is to track the motion of a simulated molecule from the diffusive standpoint, and obtain the flow velocity and temperature through sampling and averaging the IP quantities. To validate the idea and the corresponding model, several benchmark problems with Kn ˜ 10-3-10-4 have been investigated. It is shown that the IP calculations are not only accurate, but also efficient because they make possible using a time step and cell size over an order of magnitude larger than the mean collision time and mean free path, respectively.

  9. NASA/DoD Aerospace Knowledge Diffusion Research Project. Paper 30: The electronic transfer of information and aerospace knowledge diffusion

    NASA Technical Reports Server (NTRS)

    Pinelli, Thomas E.; Bishop, Ann P.; Barclay, Rebecca O.; Kennedy, John M.

    1992-01-01

    Increasing reliance on and investment in information technology and electronic networking systems presupposes that computing and information technology will play a major role in the diffusion of aerospace knowledge. Little is known, however, about actual information technology needs, uses, and problems within the aerospace knowledge diffusion process. The authors state that the potential contributions of information technology to increased productivity and competitiveness will be diminished unless empirically derived knowledge regarding the information-seeking behavior of the members of the social system - those who are producing, transferring, and using scientific and technical information - is incorporated into a new technology policy framework. Research into the use of information technology and electronic networks by U.S. aerospace engineers and scientists, collected as part of a research project designed to study aerospace knowledge diffusion, is presented in support of this assertion.

  10. Impact of diffusion limited aggregates of impurities on nematic ordering

    NASA Astrophysics Data System (ADS)

    Harkai, S.; Ambrožič, M.; Kralj, S.

    2017-02-01

    We study the impact of random bond-type disorder on two-dimensional (2D) orientational ordering of nematic liquid crystal (LC) configurations. The lattice Lebwohl-Lasher pseudospin model is used to model orientational ordering perturbed by frozen-in rod-like impurities of concentration p exhibiting the isotropic orientational probability distribution. The impurities are either (i) randomly spatially distributed or (ii) form diffusion limited aggregation (DLA)-type patterns characterized by the fractal dimensions df, where we consider cases df ∼ 1.7 and df ∼ 1.9. The degree of orientational ordering is quantified in terms of the orientational pair correlation function G(r) . Simulations reveal that the DLA pattern imposed disorder has a significantly weaker impact for a given concentration of impurities. Furthermore, if samples are quenched from the isotropic LC phase, then the fractal dimension is relatively strongly imprinted on quantitative characteristics of G(r) .

  11. Engaging farmers to inform future diffuse pollution policy in England

    NASA Astrophysics Data System (ADS)

    Vrain, Emilie; Lovett, Andrew; Nobel, Lister; Grant, Fiona; Blundell, Paul; Cleasby, Will

    2013-04-01

    Stakeholder knowledge and engagement is increasingly seen as a necessary ingredient for catchment management. Whilst many agricultural management options remain voluntary, the implementation of diffuse pollution mitigation measures will only be effective with the cooperation of stakeholders. Anthony et al. (2009) and Zhang et al. (2012) state the need for more information on the realistic farmer uptake of methods to enhance analyses of the potential for pollution mitigation. A study engaging farmers to understand current agricultural practices and their attitudes towards mitigation measures has formed part of the Demonstration Test Catchment (DTC) programme in England. Interviews with over seventy farmers were conducted during 2012 in three contrasting areas of the UK: the grassland dominated Eden catchment in the North West of England; the arable dominated Wensum catchment in East Anglia and the mixed farming of the Hampshire Avon catchment in southern England. Results from the farmer survey provide a baseline regarding current agricultural practices and give insight regarding attitudes to the adoption of other mitigation measures in the future. Opinions were obtained on eighty different measures taken from a recent guide to possible measures prepared for the UK government (Newell-Price et al., 2011). Analyses have been conducted examining how current use and attitudes towards future adoption of measures varies according to different characteristics of farm businesses. These findings will be of benefit to researchers, policy makers and farm advisers, particularly aiding decision making with respect to strategies for future implementation of programmes of measures. References. Anthony, S.G. et al., 2009. Quantitative assessment of scenarios for managing trade-off between the economic performance of agriculture and the environment and between different environmental media. Available at: http://randd.defra.gov.uk/Default

  12. Influence of topology in the evolution of coordination in complex networks under information diffusion constraints

    NASA Astrophysics Data System (ADS)

    Kasthurirathna, Dharshana; Piraveenan, Mahendra; Harré, Michael

    2014-01-01

    In this paper, we study the influence of the topological structure of social systems on the evolution of coordination in them. We simulate a coordination game ("Stag-hunt") on four well-known classes of complex networks commonly used to model social systems, namely scale-free, small-world, random and hierarchical-modular, as well as on the well-mixed model. Our particular focus is on understanding the impact of information diffusion on coordination, and how this impact varies according to the topology of the social system. We demonstrate that while time-lags and noise in the information about relative payoffs affect the emergence of coordination in all social systems, some topologies are markedly more resilient than others to these effects. We also show that, while non-coordination may be a better strategy in a society where people do not have information about the payoffs of others, coordination will quickly emerge as the better strategy when people get this information about others, even with noise and time lags. Societies with the so-called small-world structure are most conducive to the emergence of coordination, despite limitations in information propagation, while societies with scale-free topologies are most sensitive to noise and time-lags in information diffusion. Surprisingly, in all topologies, it is not the highest connected people (hubs), but the slightly less connected people (provincial hubs) who first adopt coordination. Our findings confirm that the evolution of coordination in social systems depends heavily on the underlying social network structure.

  13. Diffusion of Electronic Medical Record Based Public Hospital Information Systems.

    PubMed

    Cho, Kyoung Won; Kim, Seong Min; An, Chang-Ho; Chae, Young Moon

    2015-07-01

    This study was conducted to evaluate the adoption behavior of a newly developed Electronic Medical Record (EMR)-based information system (IS) at three public hospitals in Korea with a focus on doctors and nurses. User satisfaction scores from four performance layers were analyzed before and two times after the newly develop system was introduced to evaluate the adoption process of the IS with Rogers' diffusion theory. The 'intention to use' scores, the most important indicator for determining whether or not to adopt the IS in Rogers' confirmation stage for doctors, were very high in the third survey (4.21). In addition, the scores for 'reduced medication errors', which is the key indicator for evaluating the success of the IS, increased in the third survey for both doctors and nurses. The factors influencing 'intention to use' with a high odds ratio (>1.5) were the 'frequency of attendance of user training sessions', 'mandatory use of system', 'reduced medication errors', and 'reduced medical record documentation time' for both doctors and nurses. These findings show that the new EMR-based IS was well accepted by doctors. Both doctors and nurses also positively considered the effects of the new IS on their clinical environments.

  14. Fisher statistics for analysis of diffusion tensor directional information.

    PubMed

    Hutchinson, Elizabeth B; Rutecki, Paul A; Alexander, Andrew L; Sutula, Thomas P

    2012-04-30

    A statistical approach is presented for the quantitative analysis of diffusion tensor imaging (DTI) directional information using Fisher statistics, which were originally developed for the analysis of vectors in the field of paleomagnetism. In this framework, descriptive and inferential statistics have been formulated based on the Fisher probability density function, a spherical analogue of the normal distribution. The Fisher approach was evaluated for investigation of rat brain DTI maps to characterize tissue orientation in the corpus callosum, fornix, and hilus of the dorsal hippocampal dentate gyrus, and to compare directional properties in these regions following status epilepticus (SE) or traumatic brain injury (TBI) with values in healthy brains. Direction vectors were determined for each region of interest (ROI) for each brain sample and Fisher statistics were applied to calculate the mean direction vector and variance parameters in the corpus callosum, fornix, and dentate gyrus of normal rats and rats that experienced TBI or SE. Hypothesis testing was performed by calculation of Watson's F-statistic and associated p-value giving the likelihood that grouped observations were from the same directional distribution. In the fornix and midline corpus callosum, no directional differences were detected between groups, however in the hilus, significant (p<0.0005) differences were found that robustly confirmed observations that were suggested by visual inspection of directionally encoded color DTI maps. The Fisher approach is a potentially useful analysis tool that may extend the current capabilities of DTI investigation by providing a means of statistical comparison of tissue structural orientation.

  15. Nitrogen diffusion in hafnia and the impact of nitridation on oxygen and hydrogen diffusion: A first-principles study

    SciTech Connect

    Sathiyanarayanan, Rajesh E-mail: rajesh.sathiyanarayanan@gmail.com; Pandey, R. K.; Murali, K. V. R. M.

    2015-01-21

    Using first-principles simulations, we have computed incorporation energies and diffusion barriers of ammonia, the nitrogen molecule and atomic nitrogen in monoclinic hafnia (m-HfO{sub 2}). Our calculations show that ammonia is likely to dissociate into an NH{sub 2} molecular unit, whereas the nitrogen molecule remains as a molecule either in the interstitial space or at an oxygen lattice site. The lowest energy pathway for the diffusion of atomic nitrogen interstitials consists of the hopping of the nitrogen interstitial between neighboring three-coordinated lattice oxygen atoms that share a single Hf atom, and the barrier for such hops is determined by a switching mechanism. The substitutional nitrogen atom shows a preference for diffusion through the doubly positive oxygen vacancy-mediated mechanism. Furthermore, we have investigated the impact of nitrogen atoms on the diffusion barriers of oxygen and hydrogen interstitials in m-HfO{sub 2}. Our results show that nitrogen incorporation has a significant impact on the barriers for oxygen and hydrogen diffusion: nitrogen atoms attract oxygen and hydrogen interstitials diffusing in the vicinity, thereby slowing down (reducing) their diffusion (diffusion length)

  16. Sharing Health Information and Influencing Behavioral Intentions: The Role of Health Literacy, Information Overload, and the Internet in the Diffusion of Healthy Heart Information.

    PubMed

    Crook, Brittani; Stephens, Keri K; Pastorek, Angie E; Mackert, Michael; Donovan, Erin E

    2016-01-01

    Low health literacy remains an extremely common and problematic issue, given that individuals with lower health literacy are more likely to experience health challenges and negative health outcomes. In this study, we use the first three stages of the innovation-decision process found in the theory of diffusion of innovations (Rogers, 2003). We incorporate health literacy into a model explaining how perceived health knowledge, information sharing, attitudes, and behavior are related. Results show that health information sharing explains 33% of the variance in behavioral intentions, indicating that the communicative practice of sharing information can positively impact health outcomes. Further, individuals with high health literacy tend to share less information about heart health than those with lower health literacy. Findings also reveal that perceived heart-health knowledge operates differently than health literacy to predict health outcomes.

  17. Cellular Automata with network incubation in information technology diffusion

    NASA Astrophysics Data System (ADS)

    Guseo, Renato; Guidolin, Mariangela

    2010-06-01

    Innovation diffusion of network goods determines direct network externalities that depress sales for long periods and delay full benefits. We model this effect through a multiplicative dynamic market potential driven by a latent individual threshold embedded in a special Cellular Automata representation. The corresponding mean field approximation of its aggregate version is a Riccati equation with a closed form solution. This allows the detection of a change-point time separating an incubation period from a subsequent take-off due to a collective threshold (critical mass). Weighted nonlinear least squares are the main inferential methodology. An application is analysed with reference to USA fax machine diffusion.

  18. Microstructure-informed slow diffusion tractography in humans enhances visualisation of fibre pathways.

    PubMed

    Grinberg, Farida; Maximov, Ivan I; Farrher, Ezequiel; Shah, N Jon

    2017-09-01

    Conventional fibre tractography methods based on diffusion tensor imaging exploit diffusion anisotropy and directionality in the range of low diffusion weightings (b-values). High b-value Biexponential Diffusion Tensor Analysis reported previously has demonstrated that fractional anisotropy of the slow diffusion component is essentially higher than that of conventional diffusion tensor imaging whereas popular compartment models associate this slow diffusion component with axonal water fraction. One of the primary aims of this study is to elucidate the feasibility and potential benefits of "microstructure-informed" whole-brain slow-diffusion fibre tracking (SDIFT) in humans. In vivo diffusion-weighted images in humans were acquired in the extended range of diffusion weightings≤6000smm(-2) at 3T. Fast and slow diffusion tensors were reconstructed using the bi-exponential tensor decomposition, and a detailed statistical analysis of the relevant whole-brain tensor metrics was performed. We visualised three-dimensional fibre tracts in in vivo human brains using deterministic streamlining via the major eigenvector of the slow diffusion tensor. In particular, we demonstrated that slow-diffusion fibre tracking provided considerably higher fibre counts of long association fibres and allowed one to reconstruct more short association fibres than conventional diffusion tensor imaging. SDIFT is suggested to be useful as a complimentary method capable to enhance reliability and visualisation of the evaluated fibre pathways. It is especially informative in precortical areas where the uncertainty of the mono-exponential tensor evaluation becomes too high due to decreased anisotropy of low b-value diffusion in these areas. Benefits can be expected in assessment of the residual axonal integrity in tissues affected by various pathological conditions, in surgical planning, and in evaluation of cortical connectivity, in particular, between Brodmann's areas. Copyright © 2017 Elsevier

  19. Structural limitations of learning in a crowd: communication vulnerability and information diffusion in MOOCs.

    PubMed

    Gillani, Nabeel; Yasseri, Taha; Eynon, Rebecca; Hjorth, Isis

    2014-09-23

    Massive Open Online Courses (MOOCs) bring together a global crowd of thousands of learners for several weeks or months. In theory, the openness and scale of MOOCs can promote iterative dialogue that facilitates group cognition and knowledge construction. Using data from two successive instances of a popular business strategy MOOC, we filter observed communication patterns to arrive at the "significant" interaction networks between learners and use complex network analysis to explore the vulnerability and information diffusion potential of the discussion forums. We find that different discussion topics and pedagogical practices promote varying levels of 1) "significant" peer-to-peer engagement, 2) participant inclusiveness in dialogue, and ultimately, 3) modularity, which impacts information diffusion to prevent a truly "global" exchange of knowledge and learning. These results indicate the structural limitations of large-scale crowd-based learning and highlight the different ways that learners in MOOCs leverage, and learn within, social contexts. We conclude by exploring how these insights may inspire new developments in online education.

  20. Structural limitations of learning in a crowd: communication vulnerability and information diffusion in MOOCs

    PubMed Central

    Gillani, Nabeel; Yasseri, Taha; Eynon, Rebecca; Hjorth, Isis

    2014-01-01

    Massive Open Online Courses (MOOCs) bring together a global crowd of thousands of learners for several weeks or months. In theory, the openness and scale of MOOCs can promote iterative dialogue that facilitates group cognition and knowledge construction. Using data from two successive instances of a popular business strategy MOOC, we filter observed communication patterns to arrive at the “significant” interaction networks between learners and use complex network analysis to explore the vulnerability and information diffusion potential of the discussion forums. We find that different discussion topics and pedagogical practices promote varying levels of 1) “significant” peer-to-peer engagement, 2) participant inclusiveness in dialogue, and ultimately, 3) modularity, which impacts information diffusion to prevent a truly “global” exchange of knowledge and learning. These results indicate the structural limitations of large-scale crowd-based learning and highlight the different ways that learners in MOOCs leverage, and learn within, social contexts. We conclude by exploring how these insights may inspire new developments in online education. PMID:25244925

  1. Structural limitations of learning in a crowd: communication vulnerability and information diffusion in MOOCs

    NASA Astrophysics Data System (ADS)

    Gillani, Nabeel; Yasseri, Taha; Eynon, Rebecca; Hjorth, Isis

    2014-09-01

    Massive Open Online Courses (MOOCs) bring together a global crowd of thousands of learners for several weeks or months. In theory, the openness and scale of MOOCs can promote iterative dialogue that facilitates group cognition and knowledge construction. Using data from two successive instances of a popular business strategy MOOC, we filter observed communication patterns to arrive at the ``significant'' interaction networks between learners and use complex network analysis to explore the vulnerability and information diffusion potential of the discussion forums. We find that different discussion topics and pedagogical practices promote varying levels of 1) ``significant'' peer-to-peer engagement, 2) participant inclusiveness in dialogue, and ultimately, 3) modularity, which impacts information diffusion to prevent a truly ``global'' exchange of knowledge and learning. These results indicate the structural limitations of large-scale crowd-based learning and highlight the different ways that learners in MOOCs leverage, and learn within, social contexts. We conclude by exploring how these insights may inspire new developments in online education.

  2. The impact of hardpans and cemented layers on oxygen diffusivity in mining waste heaps: diffusion experiments and modelling studies.

    PubMed

    Kohfahl, Claus; Graupner, Torsten; Fetzer, Christian; Holzbecher, Ekkehard; Pekdeger, Asaf

    2011-08-01

    This study reports column tests and modelling results to assess the impact of hardpans and cemented layers on oxygen supply in mine waste sediments. The analysed sediment samples were obtained from a low-sulphide and low-carbonate polymetallic mine waste tailings impoundment located in the Freiberg mining district in Germany. The three samples were characterised by different degrees and types of cementation. After physical and mineralogical properties of the samples had been determined, breakthrough curves of oxygen were measured in column studies at different degrees of water saturation, and the diffusivities were assessed using a numerical modelling approach. Results demonstrate that cemented layers and hardpans in undisturbed sediments associated with fine-grained material operate as preferential pathways for diffusive gas transport during rewetting, leading to higher oxygen diffusivities compared to disturbed sediments. Under air-dry conditions, the disturbed samples show higher diffusivities than the undisturbed sample, indicating clogging of the porosity by precipitation of secondary minerals such as trivalent Fe oxyhydroxides acting as a barrier and thereby decreasing the diffusivity of the undisturbed sample. In contrast to sediments without cementation, diffusion experiments of sediments with cemented layers used in this study yield similar tortuosities in spite of their different grain size distributions, pointing to the important role of these heterogeneities for gas diffusion. Copyright © 2011 Elsevier B.V. All rights reserved.

  3. Impact of ultraviolet light during rapid thermal diffusion

    NASA Astrophysics Data System (ADS)

    Noël, S.; Ventura, L.; Slaoui, A.; Muller, J. C.; Groh, B.; Schindler, R.; Fröschle, B.; Theiler, T.

    1998-05-01

    Rapid thermal processing for junction formation is emerging as a low cost technique for solar cell as well as for other semiconductor device production. Compared to conventional furnace processing, process differences are not only in very high heating and cooling rates, but also in the incoherent emitted radiation spectrum, which can act on dopant diffusion. The photons emitted from tungsten halogen lamps go from far ultraviolet, over visible to infrared light. In this work additional mercury ultraviolet lamps are used during rapid thermal annealing to analyze the influence of high energetic photons on diffusion mechanisms. The diffusion results are discussed in terms of radiation spectrum, involving analysis of diffusion profiles and sheet resistances.

  4. How reliable is online diffusion of medical information targeting patients and families?

    PubMed Central

    Xavier-Elsas, Pedro; Bastos, Sandra Epifânio; Gaspar-Elsas, Maria Ignez C

    2015-01-01

    AIM: To determine whether online diffusion of the “Ten Warning Signs of Primary Immunodeficiency Diseases (PID)’’ adheres to accepted scientific standards. METHODS: We analyzed how reproducible is online diffusion of a unique instrument, the “Ten Warning Signs of PID”, created by the Jeffrey Modell Foundation (JMF), by Google-assisted searches among highly visited sites from professional, academic and scientific organizations; governmental agencies; and patient support/advocacy organizations. We examined the diffusion, consistency of use and adequate referencing of this instrument. Where applicable, variant versions of the instrument were examined for changes in factual content that would have practical impact on physicians or on patients and their families. RESULTS: Among the first 100 sites identified by Google search, 85 faithfully reproduced the JMF model, and correctly referenced to its source. By contrast, the other 15 also referenced the JMF source but presented one or more changes in content relative to their purported model and therefore represent uncontrolled variants, of unknown origin. Discrepancies identified in the latter included changes in factual content of the original JMF list (C), as well as removal (R) and introduction (I) of novel signs (Table 2), all made without reference to any scientific publications that might account for the drastic changes in factual content. Factual changes include changes in the number of infectious episodes considered necessary to raise suspicion of PID, as well as the inclusion of various medical conditions not mentioned in the original. Together, these changes will affect the way physicians use the instrument to consult or to inform patients, and the way patients and families think about the need for specialist consultation in view of a possible PID diagnosis. CONCLUSION: The retrieved adaptations and variants, which significantly depart from the original instrument, raise concerns about standards for

  5. In vitro diffusion of mitomycin-C into human sclera after episcleral application: impact of diffusion time.

    PubMed

    Georgopoulos, M; Vass, C; El Menyawi, I; Radda, S; Graninger, W; Menapace, R

    2000-11-01

    The purpose of this study was to investigate the impact of different diffusion times of mitomycin-C (MMC) on the intrascleral concentration vs depth profile of MMC in an experimental model. Scleral quadrants of eight human donor eyes were exposed to sponges soaked with MMC for an application time of 1 min. After irrigation with 40 ml saline, we allowed further diffusion of MMC in the sclera for 1, 5, 14 and 29 min until the specimens were further processed. A central 8 mm diameter scleral disk was horizontally dissected with a kryotome at -20 degrees C. MMC concentrations of six layers of 140 microm thickness were analysed by means of high-performance liquid chromatography. The MMC concentrations (microg g(-1)) of layer 1 were: 13.45+/- 5.9 (mean +/- S.D. at 2 min diffusion time), 7.6+/-2.5 (6 min diffusion), 5.6+/-3.1 (15 min diffusion) and 3.6+/-1.7 (30 min diffusion). The corresponding MMC concentrations of layer 6 were: 0.61+/-0.48, 1.47 +/-0.66, 1.83+/-0.42 and 2.98+/-0.97 microg g(-1). The superficial concentration of intrascleral MMC decreased with increasing diffusion time, the deep concentrations increased. After 30 min of diffusion time, equal concentrations of MMC were found in all layers. Even with current low-dose application regimens of MMC the concentrations in the inner side of the sclera rapidly increase beyond the limits of the therapeutic range. Owing to this fast diffusion of MMC, the only means of reducing ciliary body concentrations of MMC is to reduce the dose.

  6. NASA/DOD Aerospace Knowledge Diffusion Research Project. Paper 19: Computer and information technology and aerospace knowledge diffusion

    NASA Technical Reports Server (NTRS)

    Pinelli, Thomas E.; Kennedy, John M.; Barclay, Rebecca O.; Bishop, Ann P.

    1992-01-01

    To remain a world leader in aerospace, the US must improve and maintain the professional competency of its engineers and scientists, increase the research and development (R&D) knowledge base, improve productivity, and maximize the integration of recent technological developments into the R&D process. How well these objectives are met, and at what cost, depends on a variety of factors, but largely on the ability of US aerospace engineers and scientists to acquire and process the results of federally funded R&D. The Federal Government's commitment to high speed computing and networking systems presupposes that computer and information technology will play a major role in the aerospace knowledge diffusion process. However, we know little about information technology needs, uses, and problems within the aerospace knowledge diffusion process. The use of computer and information technology by US aerospace engineers and scientists in academia, government, and industry is reported.

  7. Impact of osmotic stress on protein diffusion in Lactococcus lactis.

    PubMed

    Mika, Jacek T; Schavemaker, Paul E; Krasnikov, Victor; Poolman, Bert

    2014-11-01

    We measured translational diffusion of proteins in the cytoplasm and plasma membrane of the Gram-positive bacterium Lactococcus lactis and probed the effect of osmotic upshift. For cells in standard growth medium the diffusion coefficients for cytosolic proteins (27 and 582 kDa) and 12-transmembrane helix membrane proteins are similar to those in Escherichia coli. The translational diffusion of GFP in L. lactis drops by two orders of magnitude when the medium osmolality is increased by ∼ 1.9 Osm, and the decrease in mobility is partly reversed in the presence of osmoprotectants. We find a large spread in diffusion coefficients over the full population of cells but a smaller spread if only sister cells are compared. While in general the diffusion coefficients we measure under normal osmotic conditions in L. lactis are similar to those reported in E. coli, the decrease in translational diffusion upon osmotic challenge in L. lactis is smaller than in E. coli. An even more striking difference is that in L. lactis the GFP diffusion coefficient drops much more rapidly with volume than in E. coli. We discuss these findings in the light of differences in turgor, cell volume, crowding and cytoplasmic structure of Gram-positive and Gram-negative bacteria.

  8. Aesthetical Information Impact of a Literary Text.

    ERIC Educational Resources Information Center

    Malik, M. F.

    The aim of this study was to explore the aesthetic impact of a literary text on the human mind and to extend the knowledge on how and when the information from a book enters the human brain, and if and when it starts to be processed and, possibly, memorized. Readers' responses to aesthetic texts were measured through a series of biometric…

  9. Aesthetical Information Impact of a Literary Text.

    ERIC Educational Resources Information Center

    Malik, M. F.

    The aim of this study was to explore the aesthetic impact of a literary text on the human mind and to extend the knowledge on how and when the information from a book enters the human brain, and if and when it starts to be processed and, possibly, memorized. Readers' responses to aesthetic texts were measured through a series of biometric…

  10. Astrocytic Gliotransmitter: Diffusion Dynamics and Induction of Information Processing on Tripartite Synapses

    NASA Astrophysics Data System (ADS)

    Li, Jia-Jia; Du, Meng-Meng; Wang, Rong; Lei, Jin-Zhi; Wu, Ying

    Astrocytes have important functions in the central nervous system (CNS) and are significant in our understanding of the neuronal network. Astrocytes modulate neuronal firings at both single cell level of tripartite synapses and the neuron-glial network level. Astrocytes release adenosine triphosphate (ATP) and glutamate into the neuron-glial network. These gliotransmitters diffuse over the network to form long distance signals to regulate neuron firings. In this paper, we study a neuron-glial network model that includes a diffusion of astrocytic ATP and glutamate to investigate how long distance diffusion of the gliotransmitters affects the information processing in a neuronal network. We find that gliotransmitters diffusion can compensate for the failure of information processing of interneuron network firings induced by defectively coupled synapses. Moreover, we find that calcium waves in astrocyte network and firings in interneuron network are both sensitive to the glutamate diffusion rate and feedback intensities of astrocytes on interneurons.

  11. Coupled Diffusion and Reaction Processes in Rock Matrices: Impact on Dilute Groundwater Plumes

    DTIC Science & Technology

    2015-12-28

    FINAL REPORT Coupled Diffusion and Reaction Processes in Rock Matrices : Impact on Dilute Groundwater Plumes SERDP Project ER-1685...Rock Within TCE Plume ...................................... 33 3.7 Contaminant Profiles in Rock Matrices ...42 3.9 Model Development to Assess Diffusion and Reaction in Rock Matrices . ........................ 43 4. RESULTS & DISCUSSION

  12. Cumulative effect in information diffusion: empirical study on a microblogging network.

    PubMed

    Bao, Peng; Shen, Hua-Wei; Chen, Wei; Cheng, Xue-Qi

    2013-01-01

    Cumulative effect in social contagion underlies many studies on the spread of innovation, behavior, and influence. However, few large-scale empirical studies are conducted to validate the existence of cumulative effect in information diffusion on social networks. In this paper, using the population-scale dataset from the largest Chinese microblogging website, we conduct a comprehensive study on the cumulative effect in information diffusion. We base our study on the diffusion network of message, where nodes are the involved users and links characterize forwarding relationship among them. We find that multiple exposures to the same message indeed increase the possibility of forwarding it. However, additional exposures cannot further improve the chance of forwarding when the number of exposures crosses its peak at two. This finding questions the cumulative effect hypothesis in information diffusion. Furthermore, to clarify the forwarding preference among users, we investigate both structural motif in the diffusion network and temporal pattern in information diffusion process. Findings provide some insights for understanding the variation of message popularity and explain the characteristics of diffusion network.

  13. THE PONSETI METHOD IN LATIN AMERICA: INITIAL IMPACT AND BARRIERS TO ITS DIFFUSION AND IMPLEMENTATION

    PubMed Central

    Boardman, Allison; Jayawardena, Asitha; Oprescu, Florin; Cook, Thomas; Morcuende, Jose A

    2011-01-01

    The Ponseti method for correcting clubfoot is a safe, effective, and minimally invasive treatment that has recently been implemented in Latin America. This study evaluates the initial impact and unique barriers to the diffusion of the Ponseti method throughout this region. Structured interviews were conducted with 30 physicians practicing the Ponseti method in three socioeconomically diverse countries: Chile, Peru and Guatemala. Since learning the Ponseti method, these physicians have treated approximately 1,740 clubfoot patients, with an estimated 1,705 (98%) patients treated using the Ponseti method, and 35 (2%) patients treated using surgical techniques. The barriers were classified into the following themes: physician education, health care system of the country, culture and beliefs of patients, physical distance and transport, financial barriers for patients, and parental compliance with the method. The results yielded several common barriers throughout Latin America including lack of physician education, physical distance to the treatment centers, and financial barriers for patients. Information from this study can be used to inform, and to implement and evaluate specific strategies to improve the diffusion of the Ponseti method for treating clubfoot throughout Latin America. PMID:22096416

  14. The Ponseti method in Latin America: initial impact and barriers to its diffusion and implementation.

    PubMed

    Boardman, Allison; Jayawardena, Asitha; Oprescu, Florin; Cook, Thomas; Morcuende, Jose A

    2011-01-01

    The Ponseti method for correcting clubfoot is a safe, effective, and minimally invasive treatment that has recently been implemented in Latin America. This study evaluates the initial impact and unique barriers to the diffusion of the Ponseti method throughout this region. Structured interviews were conducted with 30 physicians practicing the Ponseti method in three socioeconomically diverse countries: Chile, Peru and Guatemala. Since learning the Ponseti method, these physicians have treated approximately 1,740 clubfoot patients, with an estimated 1,705 (98%) patients treated using the Ponseti method, and 35 (2%) patients treated using surgical techniques. The barriers were classified into the following themes: physician education, health care system of the country, culture and beliefs of patients, physical distance and transport, financial barriers for patients, and parental compliance with the method. The results yielded several common barriers throughout Latin America including lack of physician education, physical distance to the treatment centers, and financial barriers for patients. Information from this study can be used to inform, and to implement and evaluate specific strategies to improve the diffusion of the Ponseti method for treating clubfoot throughout Latin America.

  15. How multiple social networks affect user awareness: The information diffusion process in multiplex networks.

    PubMed

    Li, Weihua; Tang, Shaoting; Fang, Wenyi; Guo, Quantong; Zhang, Xiao; Zheng, Zhiming

    2015-10-01

    The information diffusion process in single complex networks has been extensively studied, especially for modeling the spreading activities in online social networks. However, individuals usually use multiple social networks at the same time, and can share the information they have learned from one social network to another. This phenomenon gives rise to a new diffusion process on multiplex networks with more than one network layer. In this paper we account for this multiplex network spreading by proposing a model of information diffusion in two-layer multiplex networks. We develop a theoretical framework using bond percolation and cascading failure to describe the intralayer and interlayer diffusion. This allows us to obtain analytical solutions for the fraction of informed individuals as a function of transmissibility T and the interlayer transmission rate θ. Simulation results show that interaction between layers can greatly enhance the information diffusion process. And explosive diffusion can occur even if the transmissibility of the focal layer is under the critical threshold, due to interlayer transmission.

  16. How multiple social networks affect user awareness: The information diffusion process in multiplex networks

    NASA Astrophysics Data System (ADS)

    Li, Weihua; Tang, Shaoting; Fang, Wenyi; Guo, Quantong; Zhang, Xiao; Zheng, Zhiming

    2015-10-01

    The information diffusion process in single complex networks has been extensively studied, especially for modeling the spreading activities in online social networks. However, individuals usually use multiple social networks at the same time, and can share the information they have learned from one social network to another. This phenomenon gives rise to a new diffusion process on multiplex networks with more than one network layer. In this paper we account for this multiplex network spreading by proposing a model of information diffusion in two-layer multiplex networks. We develop a theoretical framework using bond percolation and cascading failure to describe the intralayer and interlayer diffusion. This allows us to obtain analytical solutions for the fraction of informed individuals as a function of transmissibility T and the interlayer transmission rate θ . Simulation results show that interaction between layers can greatly enhance the information diffusion process. And explosive diffusion can occur even if the transmissibility of the focal layer is under the critical threshold, due to interlayer transmission.

  17. Does Collocation Inform the Impact of Collaboration?

    PubMed Central

    Lee, Kyungjoon; Brownstein, John S.; Mills, Richard G.; Kohane, Isaac S.

    2010-01-01

    Background It has been shown that large interdisciplinary teams working across geography are more likely to be impactful. We asked whether the physical proximity of collaborators remained a strong predictor of the scientific impact of their research as measured by citations of the resulting publications. Methodology/Principal Findings Articles published by Harvard investigators from 1993 to 2003 with at least two authors were identified in the domain of biomedical science. Each collaboration was geocoded to the precise three-dimensional location of its authors. Physical distances between any two coauthors were calculated and associated with corresponding citations. Relationship between distance of coauthors and citations for four author relationships (first-last, first-middle, last-middle, and middle-middle) were investigated at different spatial scales. At all sizes of collaborations (from two authors to dozens of authors), geographical proximity between first and last author is highly informative of impact at the microscale (i.e. within building) and beyond. The mean citation for first-last author relationship decreased as the distance between them increased in less than one km range as well as in the three categorized ranges (in the same building, same city, or different city). Such a trend was not seen in other three author relationships. Conclusions/Significance Despite the positive impact of emerging communication technologies on scientific research, our results provide striking evidence for the role of physical proximity as a predictor of the impact of collaborations. PMID:21179507

  18. The impact of thermal conductivity and diffusion rates on water vapor transport through gas diffusion layers

    NASA Astrophysics Data System (ADS)

    Burlatsky, Sergei F.; Atrazhev, Vadim V.; Gummalla, Mallika; Condit, Dave A.; Liu, Fuqiang

    Proper water management in a hydrogen-fueled polymer electrolyte membrane (PEM) fuel cell is critical for performance and durability. A mathematical model has been developed to elucidate the effect of thermal conductivity and water vapor diffusion coefficient in the gas diffusion layers (GDLs). The fraction of product water removed in the vapor phase through the GDL as a function of GDL properties/set of material and component parameters and operating conditions has been calculated. The current model enables identification of conditions wherein condensation occurs in each GDL component. The model predicts the temperature gradient across various components of a PEM fuel cell, providing insight into the overall mechanism of water transport in a given cell design. The water condensation conditions and transport mode in the GDL components depend on the combination of water vapor diffusion coefficients and thermal conductivities of the GDL components. Different types of GDLs and water transport scenarios are defined in this work, based on water condensation in the GDL and fraction of water that the GDL removes through the vapor phase, respectively.

  19. Weak ties: Subtle role of information diffusion in online social networks

    NASA Astrophysics Data System (ADS)

    Zhao, Jichang; Wu, Junjie; Xu, Ke

    2010-07-01

    As a social media, online social networks play a vital role in the social information diffusion. However, due to its unique complexity, the mechanism of the diffusion in online social networks is different from the ones in other types of networks and remains unclear to us. Meanwhile, few works have been done to reveal the coupled dynamics of both the structure and the diffusion of online social networks. To this end, in this paper, we propose a model to investigate how the structure is coupled with the diffusion in online social networks from the view of weak ties. Through numerical experiments on large-scale online social networks, we find that in contrast to some previous research results, selecting weak ties preferentially to republish cannot make the information diffuse quickly, while random selection can achieve this goal. However, when we remove the weak ties gradually, the coverage of the information will drop sharply even in the case of random selection. We also give a reasonable explanation for this by extra analysis and experiments. Finally, we conclude that weak ties play a subtle role in the information diffusion in online social networks. On one hand, they act as bridges to connect isolated local communities together and break through the local trapping of the information. On the other hand, selecting them as preferential paths to republish cannot help the information spread further in the network. As a result, weak ties might be of use in the control of the virus spread and the private information diffusion in real-world applications.

  20. Weak ties: subtle role of information diffusion in online social networks.

    PubMed

    Zhao, Jichang; Wu, Junjie; Xu, Ke

    2010-07-01

    As a social media, online social networks play a vital role in the social information diffusion. However, due to its unique complexity, the mechanism of the diffusion in online social networks is different from the ones in other types of networks and remains unclear to us. Meanwhile, few works have been done to reveal the coupled dynamics of both the structure and the diffusion of online social networks. To this end, in this paper, we propose a model to investigate how the structure is coupled with the diffusion in online social networks from the view of weak ties. Through numerical experiments on large-scale online social networks, we find that in contrast to some previous research results, selecting weak ties preferentially to republish cannot make the information diffuse quickly, while random selection can achieve this goal. However, when we remove the weak ties gradually, the coverage of the information will drop sharply even in the case of random selection. We also give a reasonable explanation for this by extra analysis and experiments. Finally, we conclude that weak ties play a subtle role in the information diffusion in online social networks. On one hand, they act as bridges to connect isolated local communities together and break through the local trapping of the information. On the other hand, selecting them as preferential paths to republish cannot help the information spread further in the network. As a result, weak ties might be of use in the control of the virus spread and the private information diffusion in real-world applications.

  1. Epidemic model for information diffusion in web forums: experiments in marketing exchange and political dialog.

    PubMed

    Woo, Jiyoung; Chen, Hsinchun

    2016-01-01

    As social media has become more prevalent, its influence on business, politics, and society has become significant. Due to easy access and interaction between large numbers of users, information diffuses in an epidemic style on the web. Understanding the mechanisms of information diffusion through these new publication methods is important for political and marketing purposes. Among social media, web forums, where people in online communities disseminate and receive information, provide a good environment for examining information diffusion. In this paper, we model topic diffusion in web forums using the epidemiology model, the susceptible-infected-recovered (SIR) model, frequently used in previous research to analyze both disease outbreaks and knowledge diffusion. The model was evaluated on a large longitudinal dataset from the web forum of a major retail company and from a general political discussion forum. The fitting results showed that the SIR model is a plausible model to describe the diffusion process of a topic. This research shows that epidemic models can expand their application areas to topic discussion on the web, particularly social media such as web forums.

  2. Subtle role of latency for information diffusion in online social networks

    NASA Astrophysics Data System (ADS)

    Xiong, Fei; Wang, Xi-Meng; Cheng, Jun-Jun

    2016-10-01

    Information diffusion in online social networks is induced by the event of forwarding information for users, and latency exists widely in user spreading behaviors. Little work has been done to reveal the effect of latency on the diffusion process. In this paper, we propose a propagation model in which nodes may suspend their spreading actions for a waiting period of stochastic length. These latent nodes may recover their activity again. Meanwhile, the mechanism of forwarding information is also introduced into the diffusion model. Mean-field analysis and numerical simulations indicate that our model has three nontrivial results. First, the spreading threshold does not correlate with latency in neither homogeneous nor heterogeneous networks, but depends on the spreading and refractory parameter. Furthermore, latency affects the diffusion process and changes the infection scale. A large or small latency parameter leads to a larger final diffusion extent, but the intrinsic dynamics is different. Large latency implies forwarding information rapidly, while small latency prevents nodes from dropping out of interactions. In addition, the betweenness is a better descriptor to identify influential nodes in the model with latency, compared with the coreness and degree. These results are helpful in understanding some collective phenomena of the diffusion process and taking measures to restrain a rumor in social networks. Project supported by the National Natural Science Foundation of China (Grant Nos. 61401015 and 61271308), the Fundamental Research Funds for the Central Universities, China (Grant No. 2014JBM018), and the Talent Fund of Beijing Jiaotong University, China (Grant No. 2015RC013).

  3. Improving Estimation of Fiber Orientations in Diffusion MRI Using Inter-Subject Information Sharing

    PubMed Central

    Chen, Geng; Zhang, Pei; Li, Ke; Wee, Chong-Yaw; Wu, Yafeng; Shen, Dinggang; Yap, Pew-Thian

    2016-01-01

    Diffusion magnetic resonance imaging is widely used to investigate diffusion patterns of water molecules in the human brain. It provides information that is useful for tracing axonal bundles and inferring brain connectivity. Diffusion axonal tracing, namely tractography, relies on local directional information provided by the orientation distribution functions (ODFs) estimated at each voxel. To accurately estimate ODFs, data of good signal-to-noise ratio and sufficient angular samples are desired. This is however not always available in practice. In this paper, we propose to improve ODF estimation by using inter-subject image correlation. Specifically, we demonstrate that diffusion-weighted images acquired from different subjects can be transformed to the space of a target subject to drastically increase the number of angular samples to improve ODF estimation. This is largely due to the incoherence of the angular samples generated when the diffusion signals are reoriented and warped to the target space. To reorient the diffusion signals, we propose a new spatial normalization method that directly acts on diffusion signals using local affine transforms. Experiments on both synthetic data and real data show that our method can reduce noise-induced artifacts, such as spurious ODF peaks, and yield more coherent orientations. PMID:27892534

  4. The Diffusion of Information Technology in the Human Services: Implications for Social Work Education

    ERIC Educational Resources Information Center

    Fitch, Dale

    2005-01-01

    The spread and utilization of information technology in the human services is examined using innovation diffusion theory. This examination is contextualized within the values basis of social work. Literature from the human services, the business sector, and the social sciences regarding the role of information technology is used to promote a…

  5. Fatigue and Impact Strength of Diffusion Bonded Titanium Alloy Joints

    DTIC Science & Technology

    1989-02-01

    specimen was machined to give either a Rolls-Royce rotating bend fatigue test piece or a Hounsfield impact test piece with the bond- line at the middle...specimens were machined to give Hounsfield impact test pieces. One of the metallographic specimens was also used for microhardness and electron probe...8217high’ void level condition was 3..:i lower than that of the controls. The Hounsfield impact values obtained for the 12.7 mm dia specimens (Fig 4

  6. Information filtering based on corrected redundancy-eliminating mass diffusion.

    PubMed

    Zhu, Xuzhen; Yang, Yujie; Chen, Guilin; Medo, Matus; Tian, Hui; Cai, Shi-Min

    2017-01-01

    Methods used in information filtering and recommendation often rely on quantifying the similarity between objects or users. The used similarity metrics often suffer from similarity redundancies arising from correlations between objects' attributes. Based on an unweighted undirected object-user bipartite network, we propose a Corrected Redundancy-Eliminating similarity index (CRE) which is based on a spreading process on the network. Extensive experiments on three benchmark data sets-Movilens, Netflix and Amazon-show that when used in recommendation, the CRE yields significant improvements in terms of recommendation accuracy and diversity. A detailed analysis is presented to unveil the origins of the observed differences between the CRE and mainstream similarity indices.

  7. Coupled information diffusion--pest dynamics models predict delayed benefits of farmer cooperation in pest management programs.

    PubMed

    Rebaudo, François; Dangles, Olivier

    2011-10-01

    Worldwide, the theory and practice of agricultural extension system have been dominated for almost half a century by Rogers' "diffusion of innovation theory". In particular, the success of integrated pest management (IPM) extension programs depends on the effectiveness of IPM information diffusion from trained farmers to other farmers, an important assumption which underpins funding from development organizations. Here we developed an innovative approach through an agent-based model (ABM) combining social (diffusion theory) and biological (pest population dynamics) models to study the role of cooperation among small-scale farmers to share IPM information for controlling an invasive pest. The model was implemented with field data, including learning processes and control efficiency, from large scale surveys in the Ecuadorian Andes. Our results predict that although cooperation had short-term costs for individual farmers, it paid in the long run as it decreased pest infestation at the community scale. However, the slow learning process placed restrictions on the knowledge that could be generated within farmer communities over time, giving rise to natural lags in IPM diffusion and applications. We further showed that if individuals learn from others about the benefits of early prevention of new pests, then educational effort may have a sustainable long-run impact. Consistent with models of information diffusion theory, our results demonstrate how an integrated approach combining ecological and social systems would help better predict the success of IPM programs. This approach has potential beyond pest management as it could be applied to any resource management program seeking to spread innovations across populations.

  8. Impact of a nationwide outreach program on the diffusion of evidence-based practice in Taiwan.

    PubMed

    Chiu, Ya-Wen; Weng, Yi-Hao; Lo, Heng-Lien; Shih, Ya-Hui; Hsu, Chih-Cheng; Kuo, Ken N

    2010-10-01

    To disseminate evidence-based practice (EBP) among hospital-based health professionals, since 2007 the National Health Research Institutes (NHRI) of Taiwan has run a complex outreach program that includes information resource support and promotional campaigns. The aim is to evaluate the impact of this outreach program on the diffusion of EBP. Sixty-one regional hospitals in Taiwan. A cross-sectional, pre- and post-survey of a nationally representative sample of physicians and nurses was carried out in 2007 and 2009 to examine views related to EBP including changes in beliefs, attitudes, knowledge, skills, perceived barriers and behaviors. Physicians and nurses in the 2009 survey tended to have more knowledge and skill of EBP than their counterparts in the 2007 survey. They were less likely, however, to believe that EBP can improve patient care quality and to support the implementation of EBP. The prevalence of perceived barriers to EBP declined during the 2-year study period. In addition, physicians and nurses were more likely to access the online evidence retrieval databases according to the 2009 survey when compared with responses to the 2007 survey. The knowledge of, skill in, and behavior regarding EBP have improved among physicians and nurses of regional hospitals in Taiwan after a promotion period of 2 years and they perceive fewer barriers to EBP. These data suggest that the multifaceted nationwide promotion program of the type conducted by NHRI succeeded in diffusion and implementation of EBP among professionals.

  9. NASA/DOD Aerospace Knowledge Diffusion Research Project. Paper 8: The role of the information intermediary in the diffusion of aerospace knowledge

    NASA Technical Reports Server (NTRS)

    Pinelli, Thomas E.; Kennedy, John M.; Barclay, Rebecca O.

    1990-01-01

    The United States aerospace industry is experiencing profound changes created by a combination of domestic actions and circumstances such as airline deregulation. Other changes result from external trends such as emerging foreign competition. These circumstances intensify the need to understand the production, transfer, and utilization of knowledge as a precursor to the rapid diffusion of technology. Presented here is a conceptual framework for understanding the diffusion of technology. A conceptual framework is given for understanding the diffusion of aerospace knowledge. The framework focuses on the information channels and members of the social system associated with the aerospace knowledge diffusion process, placing particular emphasis on aerospace librarians as information intermediaries.

  10. Information filtering based on corrected redundancy-eliminating mass diffusion

    PubMed Central

    Zhu, Xuzhen; Yang, Yujie; Chen, Guilin; Medo, Matus; Tian, Hui

    2017-01-01

    Methods used in information filtering and recommendation often rely on quantifying the similarity between objects or users. The used similarity metrics often suffer from similarity redundancies arising from correlations between objects’ attributes. Based on an unweighted undirected object-user bipartite network, we propose a Corrected Redundancy-Eliminating similarity index (CRE) which is based on a spreading process on the network. Extensive experiments on three benchmark data sets—Movilens, Netflix and Amazon—show that when used in recommendation, the CRE yields significant improvements in terms of recommendation accuracy and diversity. A detailed analysis is presented to unveil the origins of the observed differences between the CRE and mainstream similarity indices. PMID:28749976

  11. Information diffusion, Facebook clusters, and the simplicial model of social aggregation: a computational simulation of simplicial diffusers for community health interventions.

    PubMed

    Kee, Kerk F; Sparks, Lisa; Struppa, Daniele C; Mannucci, Mirco A; Damiano, Alberto

    2016-01-01

    By integrating the simplicial model of social aggregation with existing research on opinion leadership and diffusion networks, this article introduces the constructs of simplicial diffusers (mathematically defined as nodes embedded in simplexes; a simplex is a socially bonded cluster) and simplicial diffusing sets (mathematically defined as minimal covers of a simplicial complex; a simplicial complex is a social aggregation in which socially bonded clusters are embedded) to propose a strategic approach for information diffusion of cancer screenings as a health intervention on Facebook for community cancer prevention and control. This approach is novel in its incorporation of interpersonally bonded clusters, culturally distinct subgroups, and different united social entities that coexist within a larger community into a computational simulation to select sets of simplicial diffusers with the highest degree of information diffusion for health intervention dissemination. The unique contributions of the article also include seven propositions and five algorithmic steps for computationally modeling the simplicial model with Facebook data.

  12. Impact of molecular diffusion on the CO2 distribution and the temperature in the mesosphere

    NASA Astrophysics Data System (ADS)

    Chabrillat, Simon; Kockarts, Gaston; Fonteyn, Dominique; Brasseur, Guy

    2002-08-01

    Modelling the energy budget in the mesosphere and lower thermosphere requires a precise evaluation of CO2 distribution in this region. This distribution is primarily determined by competition between vertical eddy diffusion and molecular diffusion. A simple algorithm is proposed to take into account both processes, at all altitudes. Using the SOCRATES bi-dimensional model of the middle atmosphere, we show that molecular diffusion has a direct impact on CO2 vertical distribution down to approximately 80 km altitude, i.e. well into the mesosphere and below the turbopause altitude. A sensitivity study with regard to different aeronomical processes shows that molecular diffusion has the deepest influence in the mesospheric polar night region. Our model shows that molecular diffusion of CO2 is responsible for a polar night mesopause 12 K warmer than if this process was neglected. Hence, dynamical models should take this process in account across the whole mesospheric altitude range.

  13. 29 CFR 1607.4 - Information on impact.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 29 Labor 4 2011-07-01 2011-07-01 false Information on impact. 1607.4 Section 1607.4 Labor... EMPLOYEE SELECTION PROCEDURES (1978) General Principles § 1607.4 Information on impact. A. Records concerning impact. Each user should maintain and have available for inspection records or other information...

  14. Effect of head impacts on diffusivity measures in a cohort of collegiate contact sport athletes

    PubMed Central

    Ford, James C.; Flashman, Laura A.; Maerlender, Arthur; Greenwald, Richard M.; Beckwith, Jonathan G.; Bolander, Richard P.; Tosteson, Tor D.; Turco, John H.; Raman, Rema; Jain, Sonia

    2014-01-01

    Objective: To determine whether exposure to repetitive head impacts over a single season affects white matter diffusion measures in collegiate contact sport athletes. Methods: A prospective cohort study at a Division I NCAA athletic program of 80 nonconcussed varsity football and ice hockey players who wore instrumented helmets that recorded the acceleration-time history of the head following impact, and 79 non–contact sport athletes. Assessment occurred preseason and shortly after the season with diffusion tensor imaging and neurocognitive measures. Results: There was a significant (p = 0.011) athlete-group difference for mean diffusivity (MD) in the corpus callosum. Postseason fractional anisotropy (FA) differed (p = 0.001) in the amygdala (0.238 vs 0.233). Measures of head impact exposure correlated with white matter diffusivity measures in several brain regions, including the corpus callosum, amygdala, cerebellar white matter, hippocampus, and thalamus. The magnitude of change in corpus callosum MD postseason was associated with poorer performance on a measure of verbal learning and memory. Conclusion: This study suggests a relationship between head impact exposure, white matter diffusion measures, and cognition over the course of a single season, even in the absence of diagnosed concussion, in a cohort of college athletes. Further work is needed to assess whether such effects are short term or persistent. PMID:24336143

  15. Spatial and Social Diffusion of Information and Influence: Models and Algorithms

    ERIC Educational Resources Information Center

    Doo, Myungcheol

    2012-01-01

    In this dissertation research, we argue that spatial alarms and activity-based social networks are two fundamentally new types of information and influence diffusion channels. Such new channels have the potential of enriching our professional experiences and our personal life quality in many unprecedented ways. First, we develop an activity driven…

  16. A Model for Determining Information Diffusion in a Family Planning Program

    ERIC Educational Resources Information Center

    Jackson, Audrey R.

    1972-01-01

    Knowledge of the existence of birth control clinics is seen as a function of proximity to clinics, friendliness of neighborhood, and propensity to discuss birth control with neighbors. A conceptual model is developed to illustrate variables contributing to the diffusion of birth control information in a public health family planning program.…

  17. A Model for Determining Information Diffusion in a Family Planning Program

    ERIC Educational Resources Information Center

    Jackson, Audrey R.

    1972-01-01

    Knowledge of the existence of birth control clinics is seen as a function of proximity to clinics, friendliness of neighborhood, and propensity to discuss birth control with neighbors. A conceptual model is developed to illustrate variables contributing to the diffusion of birth control information in a public health family planning program.…

  18. Whisper: Tracing the Spatiotemporal Process of Information Diffusion in Real Time.

    PubMed

    Cao, Nan; Lin, Yu-Ru; Sun, Xiaohua; Lazer, D; Liu, Shixia; Qu, Huamin

    2012-12-01

    When and where is an idea dispersed? Social media, like Twitter, has been increasingly used for exchanging information, opinions and emotions about events that are happening across the world. Here we propose a novel visualization design, "Whisper", for tracing the process of information diffusion in social media in real time. Our design highlights three major characteristics of diffusion processes in social media: the temporal trend, social-spatial extent, and community response of a topic of interest. Such social, spatiotemporal processes are conveyed based on a sunflower metaphor whose seeds are often dispersed far away. In Whisper, we summarize the collective responses of communities on a given topic based on how tweets were retweeted by groups of users, through representing the sentiments extracted from the tweets, and tracing the pathways of retweets on a spatial hierarchical layout. We use an efficient flux line-drawing algorithm to trace multiple pathways so the temporal and spatial patterns can be identified even for a bursty event. A focused diffusion series highlights key roles such as opinion leaders in the diffusion process. We demonstrate how our design facilitates the understanding of when and where a piece of information is dispersed and what are the social responses of the crowd, for large-scale events including political campaigns and natural disasters. Initial feedback from domain experts suggests promising use for today's information consumption and dispersion in the wild.

  19. Spatial and Social Diffusion of Information and Influence: Models and Algorithms

    ERIC Educational Resources Information Center

    Doo, Myungcheol

    2012-01-01

    In this dissertation research, we argue that spatial alarms and activity-based social networks are two fundamentally new types of information and influence diffusion channels. Such new channels have the potential of enriching our professional experiences and our personal life quality in many unprecedented ways. First, we develop an activity driven…

  20. The Diffusion of Health Information: Medicine Hucksters Can Teach Us Something.

    ERIC Educational Resources Information Center

    Simoni, Joseph J.; Ball, Richard A.

    During 1974, the role and effectiveness of the Mexican medicine huckster were examined within the context of a specified information diffusion process. Seventy-five hucksters were observed at work in three states of Mexico (Oaxaca, Michoacan, and Mexico) and in the Federal District (Mexico City area). Twenty-five sales pitches were recorded and…

  1. Codimension-Two Bifurcation, Chaos and Control in a Discrete-Time Information Diffusion Model

    NASA Astrophysics Data System (ADS)

    Ren, Jingli; Yu, Liping

    2016-12-01

    In this paper, we present a discrete model to illustrate how two pieces of information interact with online social networks and investigate the dynamics of discrete-time information diffusion model in three types: reverse type, intervention type and mutualistic type. It is found that the model has orbits with period 2, 4, 6, 8, 12, 16, 20, 30, quasiperiodic orbit, and undergoes heteroclinic bifurcation near 1:2 point, a homoclinic structure near 1:3 resonance point and an invariant cycle bifurcated by period 4 orbit near 1:4 resonance point. Moreover, in order to regulate information diffusion process and information security, we give two control strategies, the hybrid control method and the feedback controller of polynomial functions, to control chaos, flip bifurcation, 1:2, 1:3 and 1:4 resonances, respectively, in the two-dimensional discrete system.

  2. Theoretical approach to characterize the non-Markovianity and diffusion through the influx of the information

    NASA Astrophysics Data System (ADS)

    Berrada, K.

    2016-11-01

    In this paper, we study the Fisher information for a quantum system consisting of two identical qubits, each of them locally interacting with a bosonic reservoir in the same environment for non-Markovian open, dissipative quantum system. Based on the influx of the information, we propose an information-theoretical approach for characterizing the time-dependent memory effect of environment and diffusion function under the effect of the physical parameters. More precisely, an interesting monotonic relation between the time derivative of quantum Fisher information (QFI) and diffusion function behavior is observed during the time evolution. The phenomenon is that the QFI, namely the precision of estimation, changes dramatically with the environment structure. The dependence of the physical parameters shows that the increasing in the temperature will damage the amount of the QFI with respect of the ratio between the reservoir cutoff frequency and the system oscillation frequency.

  3. A case study of evaluating informatics impact on diffusion of scientific knowledge.

    PubMed

    Katz, Susan B

    2008-11-06

    This case study poster uses a newly developed framework to evaluate an informatics effort in its public health context. The electronic clearance system being evaluated provides the potential for increasing the speed and quality of scientific diffusion of knowledge, and thus translation of research into practice. A graphical logic model and tabular results of the evaluation are presented. Public health history suggests potential benefits of more timely and coordinated diffusion of scientific information.

  4. NASA/DoD aerospace knowledge diffusion research project. VIII - The role of the information intermediary in the diffusion of aerospace knowledge

    NASA Technical Reports Server (NTRS)

    Pinelli, Thomas E.; Kennedy, John M.; Barclay, Rebecca O.

    1990-01-01

    The U.S. aerospace industry is experiencing profound changes created by a combination of domestic actions and circumstances such as airline deregulation. Other changes result from external trends such as emerging foreign competition. These circumstances intensify the need to understand the production, transfer, and utilization of knowledge as a precursor to the rapid diffusion of technology. This article presents a conceptual framework for understanding the diffusion of aerospace knowledge. The framework focuses on the information channels and members of the social system associated with the aerospace knowledge diffusion process, placing particular emphasis on aerospace librarians as information intermediaries.

  5. Simultaneous registration of structural and diffusion weighed images using the full DTI information

    NASA Astrophysics Data System (ADS)

    Nadeau, Hélène; Chai, Yaqiong; Thompson, Paul; Leporé, Natasha

    2015-01-01

    Banks of high-quality, multimodal neurological images offer new possibilities for analyses based on brain registration. To take full advantage of these, current algorithms should be significantly enhanced. We present here a new brain registration method driven simultaneously by the structural intensity and the total diffusion information of MRI scans. Using the two modalities together allows for a better alignment of general and specific aspects of the anatomy. Furthermore, keeping the full diffusion tensor in the cost function, rather than only some of its scalar measures, will allow for a thorough statistical analysis once the Jacobian of the transformation is obtained.

  6. Impact of Information Entropy on Teaching Effectiveness

    ERIC Educational Resources Information Center

    Wang, Zhi-guo

    2007-01-01

    Information entropy refers to the process in which information is sent out from the information source, transmitted through information channel and acquired by information sink, while the teaching process is the one of transmitting teaching information from teachers and teaching material to students. How to improve teaching effectiveness is…

  7. Modeling bee swarming behavior through diffusion adaptation with asymmetric information sharing

    NASA Astrophysics Data System (ADS)

    Li, Jinchao; Sayed, Ali H.

    2012-12-01

    Honeybees swarm when they move to a new site for their hive. During the process of swarming, their behavior can be analyzed by classifying them as informed bees or uninformed bees, where the informed bees have some information about the destination while the uninformed bees follow the informed bees. The swarm's movement can be viewed as a network of mobile nodes with asymmetric information exchange about their destination. In these networks, adaptive and mobile agents share information on the fly and adapt their estimates in response to local measurements and data shared with neighbors. Diffusion adaptation is used to model the adaptation process in the presence of asymmetric nodes and noisy data. The simulations indicate that the models are able to emulate the swarming behavior of bees under varied conditions such as a small number of informed bees, sharing of target location, sharing of target direction, and noisy measurements.

  8. Aesthetical Information Impact of Artworks on the Human Mind.

    ERIC Educational Resources Information Center

    Malik, M. F.

    The major areas of concern in this paper are the information and aesthetical impacts of artwork on the human mind, and the modes, structures, and media of artwork which influence the formulation of aesthetical impact. The analysis of aesthetical information impact follows current discoveries in the disciplines of biocybernetics, system and…

  9. Consume, Modify, Share (CMS): The Interplay between Individual Decisions and Structural Network Properties in the Diffusion of Information

    PubMed Central

    Koren, Hila; Kaminer, Ido

    2016-01-01

    Widely used information diffusion models such as Independent Cascade Model, Susceptible Infected Recovered (SIR) and others fail to acknowledge that information is constantly subject to modification. Some aspects of information diffusion are best explained by network structural characteristics while in some cases strong influence comes from individual decisions. We introduce reinvention, the ability to modify information, as an individual level decision that affects the diffusion process as a whole. Based on a combination of constructs from the Diffusion of Innovations and the Critical Mass Theories, the present study advances the CMS (consume, modify, share) model which accounts for the interplay between network structure and human behavior and interactions. The model's building blocks include processes leading up to and following the formation of a critical mass of information adopters and disseminators. We examine the formation of an inflection point, information reach, sustainability of the diffusion process and collective value creation. The CMS model is tested on two directed networks and one undirected network, assuming weak or strong ties and applying constant and relative modification schemes. While all three networks are designed for disseminating new knowledge they differ in structural properties. Our findings suggest that modification enhances the diffusion of information in networks that support undirected connections and carries the biggest effect when information is shared via weak ties. Rogers' diffusion model and traditional information contagion models are fine tuned. Our results show that modifications not only contribute to a sustainable diffusion process, but also aid information in reaching remote areas of the network. The results point to the importance of cultivating weak ties, allowing reciprocal interaction among nodes and supporting the modification of information in promoting diffusion processes. These results have theoretical and

  10. Consume, Modify, Share (CMS): The Interplay between Individual Decisions and Structural Network Properties in the Diffusion of Information.

    PubMed

    Koren, Hila; Kaminer, Ido; Raban, Daphne Ruth

    2016-01-01

    Widely used information diffusion models such as Independent Cascade Model, Susceptible Infected Recovered (SIR) and others fail to acknowledge that information is constantly subject to modification. Some aspects of information diffusion are best explained by network structural characteristics while in some cases strong influence comes from individual decisions. We introduce reinvention, the ability to modify information, as an individual level decision that affects the diffusion process as a whole. Based on a combination of constructs from the Diffusion of Innovations and the Critical Mass Theories, the present study advances the CMS (consume, modify, share) model which accounts for the interplay between network structure and human behavior and interactions. The model's building blocks include processes leading up to and following the formation of a critical mass of information adopters and disseminators. We examine the formation of an inflection point, information reach, sustainability of the diffusion process and collective value creation. The CMS model is tested on two directed networks and one undirected network, assuming weak or strong ties and applying constant and relative modification schemes. While all three networks are designed for disseminating new knowledge they differ in structural properties. Our findings suggest that modification enhances the diffusion of information in networks that support undirected connections and carries the biggest effect when information is shared via weak ties. Rogers' diffusion model and traditional information contagion models are fine tuned. Our results show that modifications not only contribute to a sustainable diffusion process, but also aid information in reaching remote areas of the network. The results point to the importance of cultivating weak ties, allowing reciprocal interaction among nodes and supporting the modification of information in promoting diffusion processes. These results have theoretical and

  11. Maximizing Information Diffusion in the Cyber-physical Integrated Network †

    PubMed Central

    Lu, Hongliang; Lv, Shaohe; Jiao, Xianlong; Wang, Xiaodong; Liu, Juan

    2015-01-01

    Nowadays, our living environment has been embedded with smart objects, such as smart sensors, smart watches and smart phones. They make cyberspace and physical space integrated by their abundant abilities of sensing, communication and computation, forming a cyber-physical integrated network. In order to maximize information diffusion in such a network, a group of objects are selected as the forwarding points. To optimize the selection, a minimum connected dominating set (CDS) strategy is adopted. However, existing approaches focus on minimizing the size of the CDS, neglecting an important factor: the weight of links. In this paper, we propose a distributed maximizing the probability of information diffusion (DMPID) algorithm in the cyber-physical integrated network. Unlike previous approaches that only consider the size of CDS selection, DMPID also considers the information spread probability that depends on the weight of links. To weaken the effects of excessively-weighted links, we also present an optimization strategy that can properly balance the two factors. The results of extensive simulation show that DMPID can nearly double the information diffusion probability, while keeping a reasonable size of selection with low overhead in different distributed networks. PMID:26569254

  12. 41 CFR 60-3.4 - Information on impact.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 41 Public Contracts and Property Management 1 2010-07-01 2010-07-01 true Information on impact. 60... 3-UNIFORM GUIDELINES ON EMPLOYEE SELECTION PROCEDURES (1978) General Principles § 60-3.4 Information... records or other information which will disclose the impact which its tests and other selection procedures...

  13. 41 CFR 60-3.4 - Information on impact.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 41 Public Contracts and Property Management 1 2011-07-01 2009-07-01 true Information on impact. 60... 3-UNIFORM GUIDELINES ON EMPLOYEE SELECTION PROCEDURES (1978) General Principles § 60-3.4 Information... records or other information which will disclose the impact which its tests and other selection procedures...

  14. Impact of changes in diffuse radiation on the global land carbon sink.

    PubMed

    Mercado, Lina M; Bellouin, Nicolas; Sitch, Stephen; Boucher, Olivier; Huntingford, Chris; Wild, Martin; Cox, Peter M

    2009-04-23

    Plant photosynthesis tends to increase with irradiance. However, recent theoretical and observational studies have demonstrated that photosynthesis is also more efficient under diffuse light conditions. Changes in cloud cover or atmospheric aerosol loadings, arising from either volcanic or anthropogenic emissions, alter both the total photosynthetically active radiation reaching the surface and the fraction of this radiation that is diffuse, with uncertain overall effects on global plant productivity and the land carbon sink. Here we estimate the impact of variations in diffuse fraction on the land carbon sink using a global model modified to account for the effects of variations in both direct and diffuse radiation on canopy photosynthesis. We estimate that variations in diffuse fraction, associated largely with the 'global dimming' period, enhanced the land carbon sink by approximately one-quarter between 1960 and 1999. However, under a climate mitigation scenario for the twenty-first century in which sulphate aerosols decline before atmospheric CO(2) is stabilized, this 'diffuse-radiation' fertilization effect declines rapidly to near zero by the end of the twenty-first century.

  15. Positioning Education in the Information Society: The Transnational Diffusion of the Information and Communication Technology Curriculum

    ERIC Educational Resources Information Center

    Ham, Seung-Hwan; Cha, Yun-Kyung

    2009-01-01

    One of the most distinctive qualities that characterize present-day society is the social fact that people are shifting to the information age. In recent years, they have witnessed remarkable developments in information and communication technology (ICT), in which microelectronics, computers, and telecommunications have converged. Transnational…

  16. Positioning Education in the Information Society: The Transnational Diffusion of the Information and Communication Technology Curriculum

    ERIC Educational Resources Information Center

    Ham, Seung-Hwan; Cha, Yun-Kyung

    2009-01-01

    One of the most distinctive qualities that characterize present-day society is the social fact that people are shifting to the information age. In recent years, they have witnessed remarkable developments in information and communication technology (ICT), in which microelectronics, computers, and telecommunications have converged. Transnational…

  17. Impact of mechanical deformation on guest diffusion in zeolitic imidazolate frameworks.

    PubMed

    Zheng, Bin; Wang, Lian Li; Hui, Jia Chen; Du, Lifei; Du, Huiling; Zhu, Ming

    2016-03-14

    The effect of the mechanical deformation of metal-organic frameworks on guest diffusion was investigated by employing molecular dynamics simulations. Two basic deformation modes, uniaxial tensile and shear deformation, were considered. The computed shear modulus of the zeolitic imidazolate framework-8 (ZIF-8) model system was much lower than the Young's modulus, which is in agreement with the experimental results. The diffusion rate in ZIF-8 was calculated for two types of guest molecules: the nonpolar H2 and the quadrupolar CO2. Under tensile strain, the diffusion of both H2 and CO2 was found to be enhanced, whereas the diffusion rates did not change significantly under shear loading. The evolution of the internal structure of ZIF-8 was studied to determine its effect on guest diffusion. The organic-inorganic connection was identified as the source of the framework's flexibility, and therefore we focused on the N-Zn bond and the N-Zn-N angle. Under stretching deformation, the N-Zn bond is elongated and the N-Zn-N angle remains constant. Thus, the length of the C2-C2 long bond, determining the size of the 6-membered ring (6MR) gate, increases and the gate is opened, allowing for faster guest diffusion. Under shear deformation, the N-Zn bond length changes very little and the N-Zn-N angle is distorted. This results in the occurrence of three peaks in the C2-C2 bond length distribution. Although the 6MR gate is distorted, the variation of its average size is small, resulting in a very small effect on the guest diffusivity. In addition, we found that the fluctuation of the ZIF-8 cell can enhance the impact of the mechanical deformation of the host on guest diffusion.

  18. The Impact of Biofilms on the Process of Back Diffusion From a Contaminated Rock Matrix

    NASA Astrophysics Data System (ADS)

    Yungwirth, G. A.; Novakowski, K. S.; Ross, N.

    2005-12-01

    are based on a cylindrical coordinate system where one equation was developed for the rock and another for the biofilm. The solution was found using the Laplace Transform method. Preliminary results show substantial biofilm growth, confirming that the method of biofilm stimulation is viable. Preliminary analysis of data from the diffusion experiments shows the impact of biofilm presence on back diffusion to be profound.

  19. Combining land use information and small stream sampling with PCR-based methods for better characterization of diffuse sources of human fecal pollution.

    PubMed

    Peed, Lindsay A; Nietch, Christopher T; Kelty, Catherine A; Meckes, Mark; Mooney, Thomas; Sivaganesan, Mano; Shanks, Orin C

    2011-07-01

    Diffuse sources of human fecal pollution allow for the direct discharge of waste into receiving waters with minimal or no treatment. Traditional culture-based methods are commonly used to characterize fecal pollution in ambient waters, however these methods do not discern between human and other animal sources of fecal pollution making it difficult to identify diffuse pollution sources. Human-associated quantitative real-time PCR (qPCR) methods in combination with low-order headwatershed sampling, precipitation information, and high-resolution geographic information system land use data can be useful for identifying diffuse source of human fecal pollution in receiving waters. To test this assertion, this study monitored nine headwatersheds over a two-year period potentially impacted by faulty septic systems and leaky sanitary sewer lines. Human fecal pollution was measured using three different human-associated qPCR methods and a positive significant correlation was seen between abundance of human-associated genetic markers and septic systems following wet weather events. In contrast, a negative correlation was observed with sanitary sewer line densities suggesting septic systems are the predominant diffuse source of human fecal pollution in the study area. These results demonstrate the advantages of combining water sampling, climate information, land-use computer-based modeling, and molecular biology disciplines to better characterize diffuse sources of human fecal pollution in environmental waters.

  20. 40Ar/39Ar ages of lunar impact glasses: Relationships among Ar diffusivity, chemical composition, shape, and size

    NASA Astrophysics Data System (ADS)

    Zellner, N. E. B.; Delano, J. W.

    2015-07-01

    Lunar impact glasses, which are quenched melts produced during cratering events on the Moon, have the potential to provide not only compositional information about both the local and regional geology of the Moon but also information about the impact flux over time. We present in this paper the results of 73 new 40Ar/39Ar analyses of well-characterized, inclusion-free lunar impact glasses and demonstrate that size, shape, chemical composition, fraction of radiogenic 40Ar retained, and cosmic ray exposure (CRE) ages are important for 40Ar/39Ar investigations of these samples. Specifically, analyses of lunar impact glasses from the Apollo 14, 16, and 17 landing sites indicate that retention of radiogenic 40Ar is a strong function of post-formation thermal history in the lunar regolith, size, and chemical composition. This is because the Ar diffusion coefficient (at a constant temperature) is estimated to decrease by ∼3-4 orders of magnitude with an increasing fraction of non-bridging oxygens, X(NBO), over the compositional range of most lunar impact glasses with compositions from feldspathic to basaltic. Based on these relationships, lunar impact glasses with compositions and sizes sufficient to have retained ∼90% of their radiogenic Ar during 750 Ma of cosmic ray exposure at time-integrated temperatures of up to 290 K have been identified and are likely to have yielded reliable 40Ar/39Ar ages of formation. Additionally, ∼50% of the identified impact glass spheres have formation ages of ⩽500 Ma, while ∼75% of the identified lunar impact glass shards and spheres have ages of formation ⩽2000 Ma. Higher thermal stresses in lunar impact glasses quenched from hyperliquidus temperatures are considered the likely cause of poor survival of impact glass spheres, as well as the decreasing frequency of lunar impact glasses in general with increasing age. The observed age-frequency distribution of lunar impact glasses may reflect two processes: (i) diminished

  1. Impact of information technology on medicine

    SciTech Connect

    Shine, K.I.

    1996-12-31

    Although the health sciences will benefit from many of the advances in information technology that are applied to a wide variety of research areas, information technology is of particular importance to health care delivery. Developments of computerized patient records will enhance the efficiency effectiveness, and distribution of health care. As managed care programs develop, population-based information will be of increasing importance to health care providers and to the public health community. The capacity to transmit this information. 3 refs.

  2. Impact of Information Technology in Academia

    ERIC Educational Resources Information Center

    Ranjan, Jayanthi

    2008-01-01

    Purpose--The purpose of this paper is to study the provisions of information technology IT for development of academic resources and examines the effect of IT in academic institutions for sharing information. Design/methodology/approach--The paper examines the role of IT in sharing information in academic institutions and explores the IT…

  3. Environmental information system for visualizing environmental impact assessment information.

    PubMed

    Cserny, Angelika; Kovács, Zsófia; Domokos, Endre; Rédey, Akos

    2009-01-01

    The Institute of Environmental Engineering at the University of Pannonia has undertaken the challenge to develop an online environmental information system. This system is able to receive and process the collected environmental data via Internet. The authors have attached importance to the presentation of the data and have included other comprehensible information for laymen as well in order to work out visualisation techniques that are expressive and attract attention for environmental questions through the developed information system. The ways of visualizing physical and chemical parameters of surface water and the effects of motorway construction were examined.

  4. MISOE [Management Information System for Occupational Education] Impact Battery.

    ERIC Educational Resources Information Center

    Conroy, William G., Jr.

    The impact battery consists of two instruments used to obtain impact data (descriptions of the experiences of program completors during post-program life) for the Sample Data Systems of the Management Information System for Occupational Education (MISOE). The first, Massachusetts Educational Impact Instrument (MEII), is an 11-page extensive…

  5. The Information Impact: Ensuring New Product Winners.

    ERIC Educational Resources Information Center

    Trubkin, Loene

    Despite investment in new research tools and techniques, the product development success rate has not improved within the last 25 years. One way to increase the success rate is to have the right information at each stage of the process. Today, a relatively new method of gathering information--online access to electronic files called…

  6. Impact of Organizational Culture on Information Sharing

    DTIC Science & Technology

    2011-05-19

    impediment to all-source analysis , to a greater likelihood of connecting the dots, is the human or systemic resistance to sharing information.” 4...provides a framework to apply an analysis of two federal agencies within the intelligence community. Section II reviews the information sharing...unified direction for the intelligence community. Section III provides background and analysis of the Department of Homeland Security’s

  7. Man-made black holes and Big Bangs: Diffusion and integration of scientific information into everyday thinking.

    PubMed

    Courvoisier, Nelly; Clémence, Alain; Green, Eva G T

    2013-04-01

    Drawing on Social Representations Theory, this study investigates focalisation and anchoring during the diffusion of information concerning the Large Hadron Collider (LHC), the particle accelerator at the European Organisation for Nuclear Research (CERN). We hypothesised that people focus on striking elements of the message, abandoning others, that the nature of the initial information affects diffusion of information, and that information is anchored in prior attitudes toward CERN and science. A serial reproduction experiment with two generations and four chains of reproduction diffusing controversial versus descriptive information about the LHC shows a reduction of information through generations, the persistence of terminology regarding the controversy and a decrease of other elements for participants exposed to polemical information. Concerning anchoring, positive attitudes toward CERN and science increase the use of expert terminology unrelated to the controversy. This research highlights the relevance of a social representational approach in the public understanding of science.

  8. Nonrigid coregistration of diffusion tensor images using a viscous fluid model and mutual information.

    PubMed

    Van Hecke, Wim; Leemans, Alexander; D'Agostino, Emiliano; De Backer, Steve; Vandervliet, Evert; Parizel, Paul M; Sijbers, Jan

    2007-11-01

    In this paper, a nonrigid coregistration algorithm based on a viscous fluid model is proposed that has been optimized for diffusion tensor images (DTI), in which image correspondence is measured by the mutual information criterion. Several coregistration strategies are introduced and evaluated both on simulated data and on brain intersubject DTI data. Two tensor reorientation methods have been incorporated and quantitatively evaluated. Simulation as well as experimental results show that the proposed viscous fluid model can provide a high coregistration accuracy, although the tensor reorientation was observed to be highly sensitive to the local deformation field. Nevertheless, this coregistration method has demonstrated to significantly improve spatial alignment compared to affine image matching.

  9. Positional information and reaction-diffusion: two big ideas in developmental biology combine.

    PubMed

    Green, Jeremy B A; Sharpe, James

    2015-04-01

    One of the most fundamental questions in biology is that of biological pattern: how do the structures and shapes of organisms arise? Undoubtedly, the two most influential ideas in this area are those of Alan Turing's 'reaction-diffusion' and Lewis Wolpert's 'positional information'. Much has been written about these two concepts but some confusion still remains, in particular about the relationship between them. Here, we address this relationship and propose a scheme of three distinct ways in which these two ideas work together to shape biological form. © 2015. Published by The Company of Biologists Ltd.

  10. Visualising Astronomy: Using Impact to Inform

    NASA Astrophysics Data System (ADS)

    Wyatt, R.

    2013-04-01

    Pop culture has visualised asteroids in a way that has made a far greater impact in the public domain than the outreach community can ever hope to achieve. Films such as Meteor (1979), Armageddon (1997) and Deep Impact (1997) may score poorly on scientific accuracy, but they have influenced our collective consciousness. (Perhaps in a fit of pre-millennial anxiety, the late 1990s saw a host of films featuring an asteroid or comet on a collision course with Earth1.) In addition to the destruction of Earth's cities, the Millennium Falcon dodging giant tumbling boulders in The Empire Strikes Back has probably influenced more people's mental image of an asteroid belt than any other single visual.

  11. Impact of the Diffusion of Microtubule-Associated Protein EB1 on Kinesin Translocation in Vitro

    NASA Astrophysics Data System (ADS)

    Lopez, Benjamin; Valentine, Megan

    2014-03-01

    Using the slowly hydrolyzable GTP analog GMPCPP, we polymerize microtubules that recapitulate the end binding behavior of EB1 along their entire length, and investigate the impact of EB1 on kinesin translocation. Through direct observation of single molecules of EB1 fused to GFP, we find that EB1 diffuses along the microtubule lattice, and that the presence of taxol affects the rate of diffusion. To test whether EB1 presence and diffusion has an effect on kinesin-driven cargo transport, we observe quantum dot labeled kinesins walking on microtubules assembled with GMPCPP and taxol and coated with EB1. We find that the addition of EB1 significantly reduces kinesin speed compared to the no EB1 condition, but when microtubules stabilized by both taxol and GMPCPP are used, the speed reduction is nearly abolished. Our data suggest a new possible mechanism for the regulation of kinesin function by EB1 in which kinesin speed is directly modulated through the interference of EB1 diffusion. Our results also raise important questions about the effects of taxol on microtubule-MAP interactions.

  12. Impact of Internet on Cytology Information Management.

    PubMed

    Luić, Ljerka; Molnar, Livia

    2016-01-01

    Internet technologies and services impose global information standards in the sphere of healthcare as a whole, which are then implied and applied in the domain of cytology laboratories. Web-based operations form a significant operating segment of any contemporary cytology laboratory as they enable operations by the use of technology, which is usually free of the restrictions imposed by the traditional way of business (geographic area and narrow localisation of activities). In their operations, almost all healthcare organisations currently create and use electronic data anddocuments, which can originate both inside and outside the organisation. An enormous amount of information thus used and exchanged may be processed timely and in a high-quality way only by integrated information systems, given three basic safety requirements: data confidentiality, integrity and availability. In the Republic of Croatia, integration of private and public healthcare information systems has been ongoing for several years but the private healthcare does not yet operate as an integrated system. Instead, each office operates using its own separate information system, i.e. This paper elaborates the argument that the sample private cytology laboratory possesses an IT system that meets current market and stakeholder needs of the healthcare sector in Croatia, given that private doctors' offices/polyclinics use IT technologies in their operations but make only partial use of Internet capacities in the segment of communication with their business associates and patients, implying the need to continue the research on a statistically relevant sample of EU countries.

  13. The Impact of Virginia's Career Information Delivery System.

    ERIC Educational Resources Information Center

    Snipes, Juanita K.; McDaniels, Carl

    1984-01-01

    Reported the impact of Virginia's Vital Information for Education and Work (VIEW) System, which is modeled on the Michigan Occupational Information System (MOIS). Suggested that a statewide career information delivery system could serve as an impetus for generating excitement and new activities in local guidance programs. (LLL)

  14. Digital Media and Education: Cognitive Impact of Information Visualization.

    ERIC Educational Resources Information Center

    Kraidy, Ute

    2002-01-01

    Argues that like other technological innovations, the rise of the digital information age is contributing to shape people's mode of cognition. Reviews the use of computers in teaching and learning in terms of their impact on our ability to process parallel data, access information in a non-linear order, and visualize information. (Author/LRW)

  15. The Internet's Impact on Policy Evaluation: Information Compression and Credibility

    ERIC Educational Resources Information Center

    Bozeman, Barry

    2004-01-01

    As with all media, the Internet structures and frames information, rewarding some information search and decision behaviors while punishing others and, thereby, strongly influences evaluation research results and possibilities. Now that the Internet is for many evaluators the information medium of choice, the impacts of the medium on evaluation…

  16. Health information technology impact on productivity.

    PubMed

    Eastaugh, Steven R

    2012-01-01

    Managers work to achieve the greatest output for the least input effort, better balancing all factors of delivery to achieve the most with the smallest resource effort. Documentation of actual health information technology (HIT) cost savings has been elusive. Information technology and linear programming help to control hospital costs without harming service quality or staff morale. This study presents production function results from a study of hospital output during the period 2008-2011. The results suggest that productivity varies widely among the 58 hospitals as a function of staffing patterns, methods of organization, and the degree of reliance on information support systems. Financial incentives help to enhance productivity. Incentive pay for staff based on actual productivity gains is associated with improved productivity. HIT can enhance the marginal value product of nurses and staff, so that they concentrate their workday around patient care activities. The implementation of electronic health records (EHR) was associated with a 1.6 percent improvement in productivity.

  17. Impacts by point and diffuse micropollutant sources on the stream water quality at catchment scale

    NASA Astrophysics Data System (ADS)

    Petersen, M. F.; Eriksson, E.; Binning, P. J.; Bjerg, P. L.

    2012-04-01

    The water quality of surface waters is threatened by multiple anthropogenic pollutants and the large variety of pollutants challenges the monitoring and assessment of the water quality. The aim of this study was to characterize and quantify both point and diffuse sources of micropollutants impacting the water quality of a stream at catchment scale. Grindsted stream in western Jutland, Denmark was used as a study site. The stream passes both urban and agricultural areas and is impacted by severe groundwater contamination in Grindsted city. Along a 12 km reach of Grindsted stream, the potential pollution sources were identified including a pharmaceutical factory site with a contaminated old drainage ditch, two waste deposits, a wastewater treatment plant, overflow structures, fish farms, industrial discharges and diffuse agricultural and urban sources. Six water samples were collected along the stream and analyzed for general water quality parameters, inorganic constituents, pesticides, sulfonamides, chlorinated solvents, BTEXs, and paracetamol and ibuprofen. The latter two groups were not detected. The general water quality showed typical conditions for a stream in western Jutland. Minor impacts by releases of organic matter and nutrients were found after the fish farms and the waste water treatment plant. Nickel was found at concentrations 5.8 - 8.8 μg/l. Nine pesticides and metabolites of both agricultural and urban use were detected along the stream; among these were the two most frequently detected and some rarely detected pesticides in Danish water courses. The concentrations were generally consistent with other findings in Danish streams and in the range 0.01 - 0.09 μg/l; except for metribuzin-diketo that showed high concentrations up to 0.74 μg/l. The groundwater contamination at the pharmaceutical factory site, the drainage ditch and the waste deposits is similar in composition containing among others sulfonamides and chlorinated solvents (including vinyl

  18. Information Technology and Aerospace Knowledge Diffusion: Exploring the Intermediary-End User Interface in a Policy Framework.

    ERIC Educational Resources Information Center

    Pinelli, Thomas E.; And Others

    1992-01-01

    Discusses U.S. technology policy and the transfer of scientific and technical information (STI). Results of a study of knowledge diffusion in the aerospace industry are reported, including data on aerospace information intermediaries, use of computer and information technologies, and the use of NASA (National Aeronautics and Space Administration)…

  19. Impacts of Geospatial Information for Decision Making

    NASA Astrophysics Data System (ADS)

    Pearlman, F.; Coote, A.; Friedl, L.; Stewart, M.

    2012-12-01

    Geospatial information contributes to decisions by both societal and individual decision-makers. More effective use of this information is essential as issues are increasingly complex and consequences can be critical for future economic and social development. To address this, a workshop brought together analysts, communicators, officials, and researchers from academia, government, non-governmental organizations, and the private sector. A range of policy issues, management needs, and resource requirements were discussed and a wide array of analyses, geospatial data, methods of analysis, and metrics were presented for assessing and communicating the value of geospatial information. It is clear that there are many opportunities for integrating science and engineering disciplines with the social sciences for addressing societal issues that would benefit from using geospatial information and earth observations. However, these collaborations must have outcomes that can be easily communicated to decision makers. This generally requires either succinct quantitative statements of value based on rigorous models and/or user testimonials of actual applications that save real money. An outcome of the workshop is to pursue the development of a community of practice or society that encompasses a wide range of scientific, social, management, and communication disciplines and fosters collaboration across specialties, helping to build trust across social and science aspects. A resource base is also necessary. This presentation will address approaches for creating a shared knowledge database, containing a glossary of terms, reference materials and examples of case studies and the potential applications for benefit analyses.

  20. Information Exchange: The Impact of Scholarly Communication.

    ERIC Educational Resources Information Center

    Garcia, D. Linda

    1990-01-01

    Discusses issues relating to intellectual property rights that are being affected by information technologies. A 1986 study by the Office of Technology Assessment (OTA) is discussed; intellectual property law is described, including copyright, patents, and trade secrets; and the involvement of the university community in considering intellectual…

  1. Information Exchange: The Impact of Scholarly Communication.

    ERIC Educational Resources Information Center

    Garcia, D. Linda

    1990-01-01

    Discusses issues relating to intellectual property rights that are being affected by information technologies. A 1986 study by the Office of Technology Assessment (OTA) is discussed; intellectual property law is described, including copyright, patents, and trade secrets; and the involvement of the university community in considering intellectual…

  2. [The differentiation between identity crisis and identity diffusion and its impact on treatment].

    PubMed

    Foelsch, Pamela A; Odom, Anna; Arena, Helen; Krischer, Maya K; Schmeck, Klaus; Schlüter-Müller, Susanne

    2010-01-01

    The differentiation between an identity crisis, a transient phenomenon that usually results (after resolution) in a well-integrated identity with flexible and adaptive functioning, and an identity diffusion that is viewed as a basis for subsequent personality pathology, has a major impact on the selection of a treatment method. A new treatment method (Adolescent Identity Treatment, AIT), a modification of Transference Focused Psychotherapy, was developed to treat adolescents with identity diffusion in order to improve their relationships with friends, parents, and teachers and to help them acquire positive self-esteem, clarify life goals and establish a stable identity. In a case study we describe the basic approaches of AIT in assessment and treatment.

  3. Impact of uniaxial strain and doping on oxygen diffusion in CeO2

    PubMed Central

    Rushton, M. J. D.; Chroneos, A.

    2014-01-01

    Doped ceria is an important electrolyte for solid oxide fuel cell applications. Molecular dynamics simulations have been used to investigate the impact of uniaxial strain along the <100> directions and rare-earth doping (Yb, Er, Ho, Dy, Gd, Sm, Nd, and La) on oxygen diffusion. We introduce a new potential model that is able to describe the thermal expansion and elastic properties of ceria to give excellent agreement with experimental data. We calculate the activation energy of oxygen migration in the temperature range 900–1900 K for both unstrained and rare-earth doped ceria systems under tensile strain. Uniaxial strain has a considerable effect in lowering the activation energies of oxygen migration. A more pronounced increase in oxygen diffusivities is predicted at the lower end of the temperature range for all the dopants considered. PMID:25317676

  4. NASA/DoD Aerospace Knowledge Diffusion Research Project. XXIII - Information technology and aerospace knowledge diffusion: Exploring the intermediary-end user interface in a policy framework

    NASA Technical Reports Server (NTRS)

    Pinelli, Thomas E.; Barclay, Rebecca O.; Bishop, Ann P.; Kennedy, John M.

    1992-01-01

    Federal attempts to stimulate technological innovation have been unsuccessful because of the application of an inappropriate policy framework that lacks conceptual and empirical knowledge of the process of technological innovation and fails to acknowledge the relationship between knowledge production, transfer, and use as equally important components of the process of knowledge diffusion. This article argues that the potential contributions of high-speed computing and networking systems will be diminished unless empirically derived knowledge about the information-seeking behavior of members of the social system is incorporated into a new policy framework. Findings from the NASA/DoD Aerospace Knowledge Diffusion Research Project are presented in support of this assertion.

  5. NASA/DOD Aerospace Knowledge Diffusion Research Project. Paper 23: Information technology and aerospace knowledge diffusion: Exploring the intermediary-end user interface in a policy framework

    NASA Technical Reports Server (NTRS)

    Pinelli, Thomas E.; Barclay, Rebecca O.; Bishop, Ann P.; Kennedy, John M.

    1992-01-01

    Federal attempts to stimulate technological innovation have been unsuccessful because of the application of an inappropriate policy framework that lacks conceptual and empirical knowledge of the process of technological innovation and fails to acknowledge the relationship between knowled reproduction, transfer, and use as equally important components of the process of knowledge diffusion. It is argued that the potential contributions of high-speed computing and networking systems will be diminished unless empirically derived knowledge about the information-seeking behavior of the members of the social system is incorporated into a new policy framework. Findings from the NASA/DoD Aerospace Knowledge Diffusion Research Project are presented in support of this assertion.

  6. NASA/DoD Aerospace Knowledge Diffusion Research Project. XXIII - Information technology and aerospace knowledge diffusion: Exploring the intermediary-end user interface in a policy framework

    NASA Technical Reports Server (NTRS)

    Pinelli, Thomas E.; Barclay, Rebecca O.; Bishop, Ann P.; Kennedy, John M.

    1992-01-01

    Federal attempts to stimulate technological innovation have been unsuccessful because of the application of an inappropriate policy framework that lacks conceptual and empirical knowledge of the process of technological innovation and fails to acknowledge the relationship between knowledge production, transfer, and use as equally important components of the process of knowledge diffusion. This article argues that the potential contributions of high-speed computing and networking systems will be diminished unless empirically derived knowledge about the information-seeking behavior of members of the social system is incorporated into a new policy framework. Findings from the NASA/DoD Aerospace Knowledge Diffusion Research Project are presented in support of this assertion.

  7. Replacement of chlorofluorocarbons at the DOE gaseous diffusion plants: An assessment of global impacts

    SciTech Connect

    Socolof, M.L.; McCold, L.N.; Saylor, R.E.

    1997-01-01

    Three gaseous diffusion plants (GDPs) for enriching uranium maintain a large inventory of chlorofluorocarbon-114 (CFC-114) as a coolant. To address the continued use of CFC-114, an ozone-depleting substance, the US Department of Energy (DOE) considered introducing perfluorocarbons (PFCs) by the end of 1995. These PFCs would not contribute to stratospheric ozone depletion but would be larger contributors to global warming than would CFC-114. The paper reports the results of an assessment of the global impacts of four alternatives for modifying GDP coolant system operations over a three-year period beginning in 1996. The overall contribution of GDP coolant releases to impacts on ozone depletion and global warming were quantified by parameters referred to as ozone-depletion impact and global-warming impact. The analysis showed that these parameters could be used as surrogates for predicting global impacts to all resources and could provide a framework for assessing environmental impacts of a permanent coolant replacement, eliminating the need for subsequent resource-specific analyses.

  8. Evaluating the Impact of a Special Library and Information Service

    ERIC Educational Resources Information Center

    Botha, Erika; Erasmus, Rene; van Deventer, Martie

    2009-01-01

    The mere fact that a library service is being used does not mean that the service makes a difference or has a positive impact on the user. This has significant implications for Special Library and Information Services (SL&IS) that have to constantly prove that they add value. Because of the difficulty of measuring impact effectively, the…

  9. Replacement of chlorofluorocarbons (CFCs) at the DOE gaseous diffusion plants: An assessment of global impacts

    SciTech Connect

    Socolof, M.L.; Saylor, R.E.; McCold, L.N.

    1994-06-01

    The US Department of Energy (DOE) formerly operated two gaseous diffusion plants (GDPs) for enriching uranium and maintained a third shutdown GDP. These plants maintain a large inventory of dichlorotetrafluorethane (CFC-114), a cholorofluorocarbon (CFC), as a coolant. The paper evaluates the global impacts of four alternatives to modify GDP coolant system operations for a three-year period beginning in 1996. Interim modification of GDP coolant system operations has the potential to reduce stratospheric ozone depletion from GDP coolant releases while a permanent solution is studied.

  10. NASA/DOD Aerospace Knowledge Diffusion Research Project. Paper 48: Valuing information in an interactive environment

    NASA Technical Reports Server (NTRS)

    Brinberg, Herbert R.; Pinelli, Thomas E.; Barclay, Rebecca O.

    1995-01-01

    Consideration effort has been devoted over the past 30 years to developing methods and means of assessing the value of information. Two approaches - value in exchange and value in use - dominate; however, neither approach enjoys much practical application because validation schema for decision-making is missing. The approaches fail to measure objectively the real costs of acquiring information and the real benefits that information will yield. Moreover, these approaches collectively fail to provide economic justification to build and/or continue to support an information product or service. In addition, the impact of Cyberspace adds a new dimension to the problem. A new paradigm is required to make economic sense in this revolutionary information environment. In previous work, the authors explored the various approaches to measuring the value of information and concluded that, in large measure, these methods were unworkable concepts and constructs. Instead, they proposed several axioms for valuing information. Most particularly they concluded that the 'value of information cannot be measured in the absence of a specific task, objective, or goal.' This paper builds on those axioms and describes under which circumstances information can be measured in objective and actionable terms. This paper also proposes a methodology for undertaking such measures and validating the results.

  11. Relation between diffuse axonal injury and internal head structures on blunt impact.

    PubMed

    Nishimoto, T; Murakami, S

    1998-02-01

    Diffuse axonal injury (DAI) is a severe head injury, which exhibits symptoms of consciousness disturbance and is thought to occur through rotational angular acceleration. This paper analyzes the occurrence of DAI when direct impacts with translational accelerations are applied to two-dimensional head models. We constructed a human model reproducing the human head structure, as well as modified human models with some internal head structures removed. Blunt direct impacts were applied from a lateral direction to the bottom of the third ventricle, considered to be the center of impact, using an impactor. The analysis was done by comparing the macroscopic manifestation of DAI with the shear stress as the engineering index. In the analytical data obtained from the human model, shear stresses were concentrated on the corpus callosum and the brain stem, in the deep area. This agrees with regions of the DAI indicated by small hemorrhages in the corpus callosum and the brain stem. The analytical data obtained by the modified human models show that the high shear stress on the corpus callosum is influenced by the falx cerebri, while the high shear stress on the brain stem is influenced by the tentorium cerebelli and the shape of the brain. These results indicate that DAI, generally considered to be influenced by angular acceleration, may also occur through direct impact with translational acceleration. We deduced that the injury mechanism of DAI is related to the concentration of shear stress on the core of the brain, since the internal head structures influence the impact stress concentration.

  12. Affine and polynomial mutual information coregistration for artifact elimination in diffusion tensor imaging of newborns.

    PubMed

    Nielsen, Jon F; Ghugre, Nilesh R; Panigrahy, Ashok

    2004-11-01

    We have investigated the use of two different image coregistration algorithms for identifying local regions of erroneously high fractional anisotropy (FA) as derived from diffusion tensor imaging (DTI) data sets in newborns. The first algorithm uses conventional affine registration of each of the diffusion-weighted images to the unweighted (b = 0) image for each slice, while the second algorithm uses second-order polynomial warping. Similarity between images was determined using the mutual information (MI) criterion, which is the preferred 'cost' criterion for coregistration of images with significantly different image intensity distributions. We have found that subtle differences exist in the FA values resulting from affine and second-order polynomial coregistration and demonstrate that nonlinear distortions introduce artifacts of spatial extent similar to real white matter structures in the newborn subcortex. We show that polynomial coregistration systematically reduces the presence of erroneous regions of high FA and that such artifacts can be identified by visual inspection of FA maps resulting from affine and polynomial coregistrations. Furthermore, we show that nonlinear distortions may be particularly pronounced when acquiring image slices of axial orientation at the height of the nasal cavity. Finally, we show that third-order polynomial MI coregistration (using the images resulting from second-order coregistration as input) has no observable effect on the resulting FA maps.

  13. Information Filtering in Sparse Online Systems: Recommendation via Semi-Local Diffusion

    PubMed Central

    Zeng, Wei; Zeng, An; Shang, Ming-Sheng; Zhang, Yi-Cheng

    2013-01-01

    With the rapid growth of the Internet and overwhelming amount of information and choices that people are confronted with, recommender systems have been developed to effectively support users’ decision-making process in the online systems. However, many recommendation algorithms suffer from the data sparsity problem, i.e. the user-object bipartite networks are so sparse that algorithms cannot accurately recommend objects for users. This data sparsity problem makes many well-known recommendation algorithms perform poorly. To solve the problem, we propose a recommendation algorithm based on the semi-local diffusion process on the user-object bipartite network. The simulation results on two sparse datasets, Amazon and Bookcross, show that our method significantly outperforms the state-of-the-art methods especially for those small-degree users. Two personalized semi-local diffusion methods are proposed which further improve the recommendation accuracy. Finally, our work indicates that sparse online systems are essentially different from the dense online systems, so it is necessary to reexamine former algorithms and conclusions based on dense data in sparse systems. PMID:24260206

  14. Toward reliable retrieval of functional information of papillary dermis using spatially resolved diffuse reflectance spectroscopy.

    PubMed

    Chen, Yu-Wen; Guo, Jun-Yen; Tzeng, Shih-Yu; Chou, Ting-Chun; Lin, Ming-Jen; Huang, Lynn Ling-Huei; Yang, Chao-Chun; Hsu, Chao-Kai; Tseng, Sheng-Hao

    2016-02-01

    Spatially resolved diffuse reflectance spectroscopy (SRDRS) has been employed to quantify tissue optical properties and its interrogation volume is majorly controlled by the source-to-detector separations (SDSs). To noninvasively quantify properties of dermis, a SRDRS setup that includes SDS shorter than 1 mm is required. It will be demonstrated in this study that Monte Carlo simulations employing the Henyey-Greenstein phase function cannot always precisely predict experimentally measured diffuse reflectance at such short SDSs, and we speculated this could be caused by the non-negligible backward light scattering at short SDSs that cannot be properly modeled by the Henyey-Greenstein phase function. To accurately recover the optical properties and functional information of dermis using SRDRS, we proposed the use of the modified two-layer (MTL) geometry. Monte Carlo simulations and phantom experiment results revealed that the MTL probing geometry was capable of faithfully recovering the optical properties of upper dermis. The capability of the MTL geometry in probing the upper dermis properties was further verified through a swine study, and it was found that the measurement results were reasonably linked to histological findings. Finally, the MTL probe was utilized to study psoriatic lesions. Our results showed that the MTL probe was sensitive to the physiological condition of tissue volumes within the papillary dermis and could be used in studying the physiology of psoriasis.

  15. Toward reliable retrieval of functional information of papillary dermis using spatially resolved diffuse reflectance spectroscopy

    PubMed Central

    Chen, Yu-Wen; Guo, Jun-Yen; Tzeng, Shih-Yu; Chou, Ting-Chun; Lin, Ming-Jen; Huang, Lynn Ling-Huei; Yang, Chao-Chun; Hsu, Chao-Kai; Tseng, Sheng-Hao

    2016-01-01

    Spatially resolved diffuse reflectance spectroscopy (SRDRS) has been employed to quantify tissue optical properties and its interrogation volume is majorly controlled by the source-to-detector separations (SDSs). To noninvasively quantify properties of dermis, a SRDRS setup that includes SDS shorter than 1 mm is required. It will be demonstrated in this study that Monte Carlo simulations employing the Henyey-Greenstein phase function cannot always precisely predict experimentally measured diffuse reflectance at such short SDSs, and we speculated this could be caused by the non-negligible backward light scattering at short SDSs that cannot be properly modeled by the Henyey-Greenstein phase function. To accurately recover the optical properties and functional information of dermis using SRDRS, we proposed the use of the modified two-layer (MTL) geometry. Monte Carlo simulations and phantom experiment results revealed that the MTL probing geometry was capable of faithfully recovering the optical properties of upper dermis. The capability of the MTL geometry in probing the upper dermis properties was further verified through a swine study, and it was found that the measurement results were reasonably linked to histological findings. Finally, the MTL probe was utilized to study psoriatic lesions. Our results showed that the MTL probe was sensitive to the physiological condition of tissue volumes within the papillary dermis and could be used in studying the physiology of psoriasis. PMID:26977361

  16. Impact of individual interest shift on information dissemination in modular networks

    NASA Astrophysics Data System (ADS)

    Zhao, Narisa; Cui, Xuelian

    2017-01-01

    Social networks exhibit strong community structure. Many researches have been done to explore the impacts of community structure on information diffusion but few combined with human behaviors together. In this paper, we focus on how the individual interests' changing behavior impacts the dynamics of information propagation. Firstly, we propose an information dissemination model considering both the community structure and individual interest shift where social reinforcement and time decaying are taken into account. The accuracy of the model is evaluated by comparing the simulation and theoretical results. Further, the numerical results illustrate that both the community structure and the interests changing behavior have effects on the outbreak size of the information dissemination. Specially, lower modularity and higher community connection density will accelerate the speed of information propagation especially when the information maximal lifetime is shorter. In addition, the changes of individual interests in the message have a great impact on the final density of the received through increasing or decreasing the number of satisfied individuals directly. What is more, our findings suggest that when the modularity of the network is higher and the community clustering coefficient is lower individual interest shift behavior will have a heavier effect on the spread scope.

  17. Impact of diffuse mortality in a terrestrial biosphere model: stress, succession, and disease (Invited)

    NASA Astrophysics Data System (ADS)

    Dietze, M.

    2013-12-01

    Small changes in background mortality rate can have large impacts on forest composition, structure, and biogeochemical cycles. Despite this high sensitivity, the effects of mortality are absent from most ecosystem models and poorly constrained in the few models that explicitly represent mortality. Herein we explore the representation and uncertainties in diffuse mortality in the Ecosystem Demography model, a height- and successionally-structured terrestrial biosphere model. Modeled mortality is based on contributions from density independent effects, carbon balance effects, and frost effects. We also introduce a novel conceptual model for the representation of both diffuse (endemic) and epidemic forest pests and pathogens in earth system models. The sensitivity of forest mortality rates and carbon balance to different environmental factors is explored for eastern US forests and compared to national Forest Inventory and Analysis patterns. Specifically we assess the impacts of temperature, precipitation, CO2, elevation, slope, aspect, soil texture, lateral hydrology, successional status, tree size, and competitive interactions. Mortality was found to have the highest sensitivity to successional status, tree size, elevation, temperature, and CO2. Modeled sensitivity shows a strong correspondence with mortality patterns from forest inventory data. We also explore the dynamics of our conceptual disease model to represent forest responses to different disease classes, including phloem feeders, defoliators, cankers & wilts, stem rot, and root rot

  18. Impact of the emulsification-diffusion method on the development of pharmaceutical nanoparticles.

    PubMed

    Quintanar-Guerrero, David; Zambrano-Zaragoza, María de la Luz; Gutierrez-Cortez, Elsa; Mendoza-Munoz, Nestor

    2012-12-01

    Nanotechnology is having a profound impact in many scientific fields and it has become one of the most important and exciting discipline. Like all technological advances, nanotechnology has its own scientific basis with a broad interdisciplinary effect. Perhaps, we are witnessing an exponential growth of nanotechnology, reflection of this is the important increase in the number of patents, scientific papers and specialized "nano" meetings and journals. The impact in the pharmaceutical area is related to the use of colloidal drug delivery systems as carriers for bioactive agents, in particular, the nanoparticle technology. The term nanoparticles designates solid submicronic particles formed of acceptable materials (e.g. polymers, lipids, etc.) containing an active substance. It includes both nanospheres (matricial systems) and nanocapsules (membrane systems). The knowledge of the nanoparticle preparation methods is a key issue for the formulator involved with drug-delivery research and development. In general, the methods based on preformed polymers, in particular biodegradable polymers, are preferred due to their easy implementation and lower potential toxicity. One of the most widely used methods to prepare polymeric nanoparticles is emulsification-diffusion. This method has been discussed in some reviews that compile research works but has a small number of patents. In this review, the emulsification-diffusion method is discussed from a technological point of view in order to show the operating conditions and formulation variables from data extracted of recent patents and experimental works. The main idea is to provide the reader with a general guide for formulators to make decisions about the usefulness of this method to develop specific nanoparticulate systems. The first part of this review provides an overview of the emulsification-diffusion method to prepare polymeric nanoparticles, while the second part evaluates the influence of preparative variables on the

  19. Learnable Models for Information Diffusion and its Associated User Behavior in Micro-blogosphere

    DTIC Science & Technology

    2012-08-30

    distributed social interests. Thus, it is worth putting some effort to attempt to find empirical regularities and develop explanatory accounts of human ...and provide insights into underlying human communication. Our ultimate goal of this project is to develop learnable models for Report Documentation...follow on project. Fellow researchers will be interested to know what impact this research has on your particular field of science . Information

  20. Enhancing a diffusion algorithm for 4D image segmentation using local information

    NASA Astrophysics Data System (ADS)

    Lösel, Philipp; Heuveline, Vincent

    2016-03-01

    Inspired by the diffusion of a particle, we present a novel approach for performing a semiautomatic segmentation of tomographic images in 3D, 4D or higher dimensions to meet the requirements of high-throughput measurements in a synchrotron X-ray microtomograph. Given a small number of 2D-slices with at least two manually labeled segments, one can either analytically determine the probability that an intelligently weighted random walk starting at one labeled pixel will be at a certain time at a specific position in the dataset or determine the probability approximately by performing several random walks. While the weights of a random walk take into account local information at the starting point, the random walk itself can be in any dimension. Starting a great number of random walks in each labeled pixel, a voxel in the dataset will be hit by several random walks over time. Hence, the image can be segmented by assigning each voxel to the label where the random walks most likely started from. Due to the high scalability of random walks, this approach is suitable for high throughput measurements. Additionally, we describe an interactively adjusted active contours slice by slice method considering local information, where we start with one manually labeled slice and move forward in any direction. This approach is superior with respect to accuracy towards the diffusion algorithm but inferior in the amount of tedious manual processing steps. The methods were applied on 3D and 4D datasets and evaluated by means of manually labeled images obtained in a realistic scenario with biologists.

  1. Impacts of intense inward and outward ULF wave radial diffusion on the Van Allen belts

    NASA Astrophysics Data System (ADS)

    Mann, Ian; Ozeke, Louis; Rae, I. Jonathan; Murphy, Kyle

    2016-07-01

    During geomagnetic storms, the power in ultra-low frequency (ULF) waves can be orders of magnitude larger than that predicted by statistics determined from an entire solar cycle. This is especially true during the main phase and early recovery phase. These periods of enhanced storm-time ULF wave power can have significant impacts on the morphology and structure of the Van Allen belts. Either fast inward or outward radial diffusion can result, depending on the profiles of the electron phase space density and the outer boundary condition at the edge of the belts. Small changes in the time sequence of powerful ULF waves, and the time sequence of any magnetopause shadowing or the recovery of plamasheet sources relative to the ULF wave occurrence, have a remarkable impact on the resulting structure of the belts. The overall impact of the enhanced ULF wave power is profound, but the response can be very different depending on the available source flux in the plasmasheet. We review these impacts by examining ultra-relativistic electron dynamics during seemingly different storms during the Van Allen Probe era, including during the Baker et al. third radiation belt, and show the observed behaviour can be largely explained by differences in the time sequence of events described above.

  2. NASA/DOD Aerospace Knowledge Diffusion Research Project. Paper 5: Aerospace librarians and technical information specialists as information intermediaries: A report of phase 2 activities of the NASA/DOD Aerospace Knowledge Diffusion Research Project

    NASA Technical Reports Server (NTRS)

    Pinelli, Thomas E.; Kennedy, John M.

    1990-01-01

    The objective of the NASA/DOD Aerospace Knowledge Diffusion Research Project is to provide descriptive and analytical data regarding the flow of scientific and technical information (STI) at the individual, organizational, national, and international levels, placing emphasis on the systems used to diffuse the results of federally funded aerospace STI. An overview of project assumptions, objectives, and design is presented and preliminary results of the phase 2 aerospace library survey are summarized. Phase 2 addressed aerospace knowledge transfer and use within the larger social system and focused on the flow of aerospace STI in government and industry and the role of the information intermediary in knowledge transfer.

  3. The Internet's impact on policy evaluation: information compression and credibility.

    PubMed

    Bozeman, Barry

    2004-04-01

    As with all media, the Internet structures and frames information, rewarding some information search and decision behaviors while punishing others and, thereby, strongly influences evaluation research results and possibilities. Now that the Internet is for many evaluators the information medium of choice, the impacts of the medium on evaluation deserve careful attention. The objective of this article is to lay groundwork for a theory of the impact of the Internet on evaluation and policy analysis. Questions addressed include the following: (a) What is the impact of the Internet on the evaluator's professional role, work norms, and work habits? (b) Does the use of the Internet affect who is an evaluator or the meaning of professional evaluation? and (c) How does evaluation via Internet affect the technical quality and credibility of evaluation? A key thesis is that the Internet compresses information in the sense that it is not always easy to distinguish among information resources and, especially, the authority of the information provider and the nature of the knowledge warrant. On one hand, the Internet's information compression seems to hold potential for the democratization of evaluation. On the other hand, the diminished ability to make quality distinctions about evaluation-relevant information may undercut the legitimacy of evaluation.

  4. Small is big: Interactive Trumps passive information in breaking information barriers and impacting behavioral antecedents

    DOE PAGES

    Beck, Ariane L.; Lakkaraju, Kiran; Rai, Varun; ...

    2017-01-18

    The wealth of information available on seemingly every topic creates a considerable challenge both for information providers trying to rise above the noise and discerning individuals trying to find relevant, trustworthy information. We approach this information problem by investigating how passive versus interactive information interventions can impact the antecedents of behavior change using the context of solar energy adoption, where persistent information gaps are known to reduce market potential. We use two experiments to investigate the impact of both passive and interactive approaches to information delivery on the antecedents (attitudes, subjective norms, and perceived behavioral control in the Theory ofmore » Planned Behavior) of intentions and behavior, as well as their effect on intentions and behavior directly. The passive information randomized control trial delivered via Amazon Mechanical Turk tests the effectiveness of delivering the same content in a single message versus multiple shorter messages. The interactive information delivery uses an online (mobile and PC) trivia-style gamification platform. Both experiments use the same content and are carried out over a two-week time period. Lastly, our findings suggest that interactive, gamified information has greater impact than passive information, and that shorter multiple messages of passive information are more effective than a single passive message.« less

  5. Small Is Big: Interactive Trumps Passive Information in Breaking Information Barriers and Impacting Behavioral Antecedents.

    PubMed

    Beck, Ariane L; Lakkaraju, Kiran; Rai, Varun

    2017-01-01

    The wealth of information available on seemingly every topic creates a considerable challenge both for information providers trying to rise above the noise and discerning individuals trying to find relevant, trustworthy information. We approach this information problem by investigating how passive versus interactive information interventions can impact the antecedents of behavior change using the context of solar energy adoption, where persistent information gaps are known to reduce market potential. We use two experiments to investigate the impact of both passive and interactive approaches to information delivery on the antecedents (attitudes, subjective norms, and perceived behavioral control in the Theory of Planned Behavior) of intentions and behavior, as well as their effect on intentions and behavior directly. The passive information randomized control trial delivered via Amazon Mechanical Turk tests the effectiveness of delivering the same content in a single message versus multiple shorter messages. The interactive information delivery uses an online (mobile and PC) trivia-style gamification platform. Both experiments use the same content and are carried out over a two-week time period. Our findings suggest that interactive, gamified information has greater impact than passive information, and that shorter multiple messages of passive information are more effective than a single passive message.

  6. Small Is Big: Interactive Trumps Passive Information in Breaking Information Barriers and Impacting Behavioral Antecedents

    PubMed Central

    2017-01-01

    The wealth of information available on seemingly every topic creates a considerable challenge both for information providers trying to rise above the noise and discerning individuals trying to find relevant, trustworthy information. We approach this information problem by investigating how passive versus interactive information interventions can impact the antecedents of behavior change using the context of solar energy adoption, where persistent information gaps are known to reduce market potential. We use two experiments to investigate the impact of both passive and interactive approaches to information delivery on the antecedents (attitudes, subjective norms, and perceived behavioral control in the Theory of Planned Behavior) of intentions and behavior, as well as their effect on intentions and behavior directly. The passive information randomized control trial delivered via Amazon Mechanical Turk tests the effectiveness of delivering the same content in a single message versus multiple shorter messages. The interactive information delivery uses an online (mobile and PC) trivia-style gamification platform. Both experiments use the same content and are carried out over a two-week time period. Our findings suggest that interactive, gamified information has greater impact than passive information, and that shorter multiple messages of passive information are more effective than a single passive message. PMID:28099478

  7. Office Automation and Information Technology Trends--Their Impact on Libraries and Information Center Management.

    ERIC Educational Resources Information Center

    Mason, Robert M.

    1986-01-01

    Reviews recent research on the rate of implementation and impacts of office automation (i.e., expanding microcomputer use, expert systems, electronic publishing) and outlines how these impacts may lead to changes in roles and services of libraries and information professionals. (Author/MBR)

  8. Office Automation and Information Technology Trends--Their Impact on Libraries and Information Center Management.

    ERIC Educational Resources Information Center

    Mason, Robert M.

    1986-01-01

    Reviews recent research on the rate of implementation and impacts of office automation (i.e., expanding microcomputer use, expert systems, electronic publishing) and outlines how these impacts may lead to changes in roles and services of libraries and information professionals. (Author/MBR)

  9. Impacts of physicians' usage of a mobile information system.

    PubMed

    Harkke, Ville

    2006-01-01

    Healthcare professionals are increasingly using handheld devices in their practice. The applications for the handhelds are numerous and their usage contexts and environments vary. But the impact these mobile systems have on physicians' work has been somewhat unclear. This paper sets out to explain the impacts of a mobile information system by presenting findings from an interview study conducted on users of a medical information system running on a Nokia 9210 Communicator. The impact on the work routines of the users was rather limited, despite the generally positive attitude towards the system. The actual usage patterns and the settings in which the system is used vary, and along with these the perceived impacts of the system on the work habits and the routines of the users.

  10. Amplifying diffusion of health information in low-literate populations through adult education health literacy classes.

    PubMed

    Freedman, Ariela M; Miner, Kathleen R; Echt, Katharina V; Parker, Ruth; Cooper, Hannah L F

    2011-01-01

    Over the next decade, as literacy rates are predicted to decline, the health care sector faces increasing challenges to effective communication with low-literate groups. Considering the rising costs of health care and the forthcoming changes in the American health care system, it is imperative to find nontraditional avenues through which to impart health knowledge and functional skills. This article draws on classroom observations and qualitative interviews with 21 students and 3 teachers in an adult education health literacy class to explore the efficacy of using adult education courses to teach functional health literacy skills to low-literate populations. Data were analyzed using a combination of thematic and content analyses. Results describe the motivation of students to share information within the classroom and with friends and family outside the classroom. This article also provides several recommendations to help ensure accuracy of diffused information both within and outside of the classroom. Ultimately, this study suggests that the adult education system is in a prime position to impart functional health literacy skills to low-literate populations in the classroom. Significantly, this study demonstrates that adult education students themselves may be a powerful vehicle for health communication beyond the walls of the classroom.

  11. Diffusive loss of argon in response to melt vein formation in polygenetic impact melt breccias

    NASA Astrophysics Data System (ADS)

    Mercer, Cameron M.; Hodges, Kip V.

    2017-08-01

    Many planetary surfaces in the solar system have experienced prolonged bombardment. With each impact, new rocks can be assembled that incorporate freshly generated impact melts with fragments of older rocks. Some breccias can become polygenetic, containing multiple generations of impact melt products, and can potentially provide important insights into the extensive bombardment history of a region. However, the amount of chronological information that can be extracted from such samples depends on how well the mineral isotopic systems of geochronometers can preserve the ages of individual melt generations without being disturbed by younger events. We model the thermal evolution of impact melt veins and the resulting loss of Ar from K-bearing phases common in impact melt breccias to assess the potential for preserving the 40Ar/39Ar ages of individual melt generations. Our model results demonstrate that millimeter-scale, clast-free melt veins cause significant heating of adjacent host rock minerals and can cause detectable Ar loss in contact zones that are generally thinner than, and at most about the same thickness as, the vein width. The incorporation of cold clasts in melt veins reduces the magnitudes of heating and Ar loss in the host rocks, and Ar loss can be virtually undetectable for sufficiently clast-rich veins. Quantitative evidence of the timing of impacts, as measured with the 40Ar/39Ar method, can be preserved in polygenetic impact melt breccias, particularly for those containing millimeter-scale bodies of clast-bearing melt products.

  12. Impact of post-processing methods on apparent diffusion coefficient values.

    PubMed

    Zeilinger, Martin Georg; Lell, Michael; Baltzer, Pascal Andreas Thomas; Dörfler, Arnd; Uder, Michael; Dietzel, Matthias

    2017-03-01

    The apparent diffusion coefficient (ADC) is increasingly used as a quantitative biomarker in oncological imaging. ADC calculation is based on raw diffusion-weighted imaging (DWI) data, and multiple post-processing methods (PPMs) have been proposed for this purpose. We investigated whether PPM has an impact on final ADC values. Sixty-five lesions scanned with a standardized whole-body DWI-protocol at 3 T served as input data (EPI-DWI, b-values: 50, 400 and 800 s/mm(2)). Using exactly the same ROI coordinates, four different PPM (ADC_1-ADC_4) were executed to calculate corresponding ADC values, given as [10(-3) mm(2)/s] of each lesion. Statistical analysis was performed to intra-individually compare ADC values stratified by PPM (Wilcoxon signed-rank tests: α = 1 %; descriptive statistics; relative difference/∆; coefficient of variation/CV). Stratified by PPM, mean ADCs ranged from 1.136-1.206 *10(-3) mm(2)/s (∆ = 7.0 %). Variances between PPM were pronounced in the upper range of ADC values (maximum: 2.540-2.763 10(-3) mm(2)/s, ∆ = 8 %). Pairwise comparisons identified significant differences between all PPM (P ≤ 0.003; mean CV = 7.2 %) and reached 0.137 *10(-3) mm(2)/s within the 25th-75th percentile. Altering the PPM had a significant impact on the ADC value. This should be considered if ADC values from different post-processing methods are compared in patient studies. • Post-processing methods significantly influenced ADC values. • The mean coefficient of ADC variation due to PPM was 7.2 %. • To achieve reproducible ADC values, standardization of post-processing is recommended.

  13. The Impact of New Informational Technology on Education in Wyoming.

    ERIC Educational Resources Information Center

    Dolly, John; And Others

    Educational changes in Wyoming that are linked to the emergence of new informational technologies are considered. Attention is directed to the following topics: assumptions for Wyoming educators as they plan to respond to the impact of technology on teacher education; the importance of educational goals and objectives; the national climate…

  14. Impact of adding foreign genomic information on Mexican Holstein imputation

    USDA-ARS?s Scientific Manuscript database

    The impact of adding US and Canada genomic information to the imputation of Mexican Holstein genotypes was measured by comparing 3 scenarios: 1) 2,018 Mexican genotyped animals; 2) animals from scenario 1 plus 886 related North American animals; and 3) animals from scenario 1 and all North American ...

  15. Identifying the main paths of information diffusion in online social networks

    NASA Astrophysics Data System (ADS)

    Zhu, Hengmin; Yin, Xicheng; Ma, Jing; Hu, Wei

    2016-06-01

    Recently, an increasing number of researches on relationship strength show that there are some socially active links in online social networks. Furthermore, it is likely that there exist main paths which play the most significant role in the process of information diffusion. Although much of previous work has focused on the pathway of a specific event, there are hardly any scholars that have extracted the main paths. To identify the main paths of online social networks, we proposed a method which measures the weights of links based on historical interaction records. The influence of node based on forwarding amount is quantified and top-ranked nodes are selected as the influential users. The path importance is evaluated by calculating the probability that a message would spread via this path. We applied our method to a real-world network and found interesting insights. Each influential user can access another one via a short main path and the distribution of main paths shows significant community effect.

  16. Direct measurement of VOC diffusivities in tree tissues: impacts on tree-based phytoremediation and plant contamination.

    PubMed

    Baduru, Krishna K; Trapp, Stefan; Burken, Joel G

    2008-02-15

    Recent discoveries in the phytoremediation of volatile organic compounds (VOCs) show that vapor-phase transport into roots leads to VOC removal from the vadose zone and diffusion and volatilization out of plants is an important fate following uptake. Volatilization to the atmosphere constitutes one fundamental terminal fate processes for VOCs that have been translocated from contaminated soil or groundwater, and diffusion constitutes the mass transfer mechanism to the plant-atmosphere interface. Therefore, VOC diffusion through woody plant tissues, that is, xylem, has a direct impact on contaminant fate in numerous vegetation-VOC interactions, including the phytoremediation of soil vapors and dissolved aqueous-phase contaminants. The diffusion of VOCs through freshly excised tree tissue was directly measured for common groundwater contaminants, chlorinated compounds such as trichloroethylene, perchloroethene, and tetrachloroethane and aromatic hydrocarbons such as benzene, toluene, and methyl tert-butyl ether. All compounds tested are currently being treated at full scale with tree-based phytoremediation. Diffusivities were determined by modeling the diffusive transport data with a one-dimensional diffusive flux model, developed to mimic the experimental arrangement. Wood-water partition coefficients were also determined as needed for the model application. Diffusivities in xylem tissues were found to be inversely related to molecular weight, and values determined herein were compared to previous modeling on the basis of a tortuous diffusion path in woody tissues. The comparison validates the predictive model for the first time and allows prediction for other compounds on the basis of chemical molecular weight and specific plant properties such as water, lignin, and gas contents. This research provides new insight into phytoremediation efforts and into potential fruit contamination for fruit-bearing trees, specifically establishing diffusion rates from the

  17. [The impact of information and communication technologies on nurse retention].

    PubMed

    Gagnon, Marie-Pierre; Breton, Erik; Paré, Guy; Courcy, François; Côté, José; Trépanier, Amélie; Fortin, Jean-Paul; Rouillon, F

    2013-01-01

    The purpose of this study was to determine the potential impact of information and communication technologies (ICTs) on nursing practice and nurse retention in remote, intermediate and peripheral regions of Quebec, Canada. A qualitative study using semi-structured interviews (n=21) was conducted among nursing managers from 16 health and social services centers (French acronym: CSSS) in the province of Quebec. The study found that a range of ICT applications are used, though not to the same extent in all organizations. The participants assessed the impact of computerization and telehealth applications on nursing practice and emphasized the relationships between telehealth and nurse retention, particularly through professional development. The participants also reported that ICTs can have different impacts on nurse retention (i.e. little or no impact, unclear impact, or indirect positive impact). The main findings indicate significant heterogeneity, both in terms of the nursing shortage and in terms of the integration of ICT in nursing practice. While focusing on a comparative approach, future research should further explore the impact of ICT on nursing practice and, indirectly, on nurse retention, which requires a contextual approach to ICT applications and workplaces and an analysis of staff characteristics.

  18. Technology diffusion of anesthesia information management systems into academic anesthesia departments in the United States.

    PubMed

    Stol, Ilana S; Ehrenfeld, Jesse M; Epstein, Richard H

    2014-03-01

    Anesthesia information management systems (AIMS) are electronic health records that automatically import vital signs from patient monitors and allow for computer-assisted creation of the anesthesia record. When most recently surveyed in 2007, it was estimated that at least 16% of U.S. academic hospitals (i.e., with an anesthesia residency program) had installed an AIMS. At least an additional 28% reported that they were in the process of implementing, or searching for an AIMS. In this study, we updated the adoption figures as of May 2013 and examined the historical trend of AIMS deployment in U.S. anesthesia residency programs from the perspective of the theory of diffusion of technologic innovations. Questionnaires were sent by e-mail to program directors or their identified contact individuals at the 130 U.S. anesthesiology residency programs accredited as of June 30, 2012 by the Accreditation Council for Graduate Medical Education. The questionnaires asked whether the department had an AIMS, the year of installation, and, if not present, whether there were plans to install an AIMS within the next 12 months. Follow-up e-mails and phone calls were made until responses were obtained from all programs. Results were collected between February and May 2013. Implementation percentages were determined using the number of accredited anesthesia residency programs at the start of each academic year between 1987 and 2013 and were fit to a logistic regression curve using data through 2012. Responses were received from all 130 programs. Eighty-seven (67%) reported that they currently are using an AIMS. Ten programs without a current AIMS responded that they would be installing an AIMS within 12 months of the survey. The rate of AIMS adoption by year was well fit by a logistic regression curve (P = 0.90). By the end of 2014, approximately 75% of U.S. academic anesthesiology departments will be using an AIMS, with 84% adoption expected between 2018 and 2020. Historical adoption

  19. Cellular automata models for diffusion of information and highway traffic flow

    NASA Astrophysics Data System (ADS)

    Fuks, Henryk

    diffusion of information. We also define a new class of automata networks which incorporates non-local interactions, and discuss its applicability in modeling of diffusion of innovations.

  20. Domestication and early agriculture in the Mediterranean Basin: Origins, diffusion, and impact

    PubMed Central

    Zeder, Melinda A.

    2008-01-01

    The past decade has witnessed a quantum leap in our understanding of the origins, diffusion, and impact of early agriculture in the Mediterranean Basin. In large measure these advances are attributable to new methods for documenting domestication in plants and animals. The initial steps toward plant and animal domestication in the Eastern Mediterranean can now be pushed back to the 12th millennium cal B.P. Evidence for herd management and crop cultivation appears at least 1,000 years earlier than the morphological changes traditionally used to document domestication. Different species seem to have been domesticated in different parts of the Fertile Crescent, with genetic analyses detecting multiple domestic lineages for each species. Recent evidence suggests that the expansion of domesticates and agricultural economies across the Mediterranean was accomplished by several waves of seafaring colonists who established coastal farming enclaves around the Mediterranean Basin. This process also involved the adoption of domesticates and domestic technologies by indigenous populations and the local domestication of some endemic species. Human environmental impacts are seen in the complete replacement of endemic island faunas by imported mainland fauna and in today's anthropogenic, but threatened, Mediterranean landscapes where sustainable agricultural practices have helped maintain high biodiversity since the Neolithic. PMID:18697943

  1. The impacts of geometry and binding on CaMKII diffusion and retention in dendritic spines

    PubMed Central

    Byrne, Michael J.; Waxham, M. Neal

    2013-01-01

    We used a particle-based Monte Carlo simulation to dissect the regulatory mechanism of molecular translocation of CaMKII, a key regulator of neuronal synaptic function. Geometry was based upon measurements from EM reconstructions of dendrites in CA1 hippocampal pyramidal neurons. Three types of simulations were performed to investigate the effects of geometry and other mechanisms that control CaMKII translocation in and out of dendritic spines. First, the diffusional escape rate of CaMKII from model spines of varied morphologies was examined. Second, a postsynaptic density (PSD) was added to study the impact of binding sites on this escape rate. Third, translocation of CaMKII from dendrites and trapping in spines was investigated using a simulated dendrite. Based on diffusion alone, a spine of average dimensions had the ability to retain CaMKII for duration of ~4 s. However, binding sites mimicking those in the PSD controlled the residence time of CaMKII in a highly nonlinear manner. In addition, we observed that F-actin at the spine head/neck junction had a significant impact on CaMKII trapping in dendritic spines. We discuss these results in the context of possible mechanisms that may explain the experimental results that have shown extended accumulation of CaMKII in dendritic spines during synaptic plasticity and LTP induction. PMID:21104309

  2. Extracting Diffusion Constants from Echo-Time-Dependent PFG NMR Data Using Relaxation-Time Information

    NASA Astrophysics Data System (ADS)

    Vandusschoten, D.; Dejager, P. A.; Vanas, H.

    Heterogeneous (bio)systems are often characterized by several water-containing compartments that differ in relaxation time values and diffusion constants. Because of the relatively small differences among these diffusion constants, nonoptimal measuring conditions easily lead to the conclusion that a single diffusion constant suffices to describe the water mobility in a heterogeneous (bio)system. This paper demonstrates that the combination of a T2 measurement and diffusion measurements at various echo times (TE), based on the PFG MSE sequence, enables the accurate determination of diffusion constants which are less than a factor of 2 apart. This new method gives errors of the diffusion constant below 10% when two fractions are present, while the standard approach of a biexponential fit to the diffusion data in identical circumstances gives larger (>25%) errors. On application of this approach to water in apple parenchyma tissue, the diffusion constant of water in the vacuole of the cells ( D = 1.7 × 10 -9 m 2/s) can be distinguished from that of the cytoplasm ( D = 1.0 × 10 -9 m 2/s). Also, for mung bean seedlings, the cell size determined by PFG MSE measurements increased from 65 to 100 μm when the echo time increased from 150 to 900 ms, demonstrating that the interpretation of PFG SE data used to investigate cell sizes is strongly dependent on the T2 values of the fractions within the sample. Because relaxation times are used to discriminate the diffusion constants, we propose to name this approach diffusion analysis by relaxation- time- separated (DARTS) PFG NMR.

  3. Impact of Changes in Diffuse Radiation on the Global Land Carbon Sink, 1901-2100

    NASA Astrophysics Data System (ADS)

    Mercado, L.; Bellouin, N.; Sitch, S.; Boucher, O.; Huntingford, C.; Wild, M.; Cox, P. M.

    2009-04-01

    Recent observational and theoretical studies have shown that changes in surface radiation that lead to increasing diffuse surface irradiance, enhance plant photosynthesis (Gu et al., 2003, Niyogi et al., 2004, Oliveira et al., 2007, Roderick et al., 2001). Solar radiation reaching the land surface has changed over the industrial era due to aerosols emitted from volcanoes and various anthropogenic sources (Kvalevag and Myhre, 2007). Such changes in total surface radiation are accompanied by changes in direct and diffuse surface solar radiation. Current global climate-carbon models do include the effects of changes in total surface radiation on the land biosphere but neglect the positive effects of increasing diffuse fraction on plant photosynthesis. In this study we estimate for the first time, the impact of variations in diffuse fraction on the land carbon sink using a global model (Mercado et al., 2007) modified to account for the effects of variations in both direct and diffuse radiation on canopy photosynthesis. We use meteorological forcing from the Climate Research Unit Data set. Additionally short wave and photosynthetic active radiation are reconstructed from the Hadley centre climate model, which accounts for the scattering and absorption of light by tropospheric and stratospheric aerosols and change in cloud properties due to indirect aerosol effects. References Gu L.H., Baldocchi D.D., Wofsy S.C., Munger J.W., Michalsky J.J., Urbanski S.P. & Boden T.A. (2003) Response of a deciduous forest to the Mount Pinatubo eruption: Enhanced photosynthesis. Science, 299, 2035-2038. M. M. Kvalevag and G. Myhre, J. Clim. 20, 4874 (2007). Mercado L.M., Huntingford C., Gash J.H.C., Cox P.M. & Jogireddy V. (2007) Improving the representation of radiation interception and photosynthesis for climate model applications. Tellus Series B-Chemical and Physical Meteorology, 59, 553-565. Niyogi D., Chang H.I., Saxena V.K., Holt T., Alapaty K., Booker F., Chen F., Davis K

  4. Impact of implanted phosphorus on the diffusivity of boron and its applicability to silicon solar cells

    NASA Astrophysics Data System (ADS)

    Schrof, Julian; Müller, Ralph; Reedy, Robert C.; Benick, Jan; Hermle, Martin

    2015-07-01

    Boron diffusivity reduction in extrinsically doped silicon was investigated in the context of a process combination consisting of BBr3 furnace diffusion and preceding Phosphorus ion implantation. The implantation of Phosphorus leads to a substantial blocking of Boron during the subsequent Boron diffusion. First, the influences of ion implantation induced point defects as well as the initial P doping on B diffusivity were studied independently. Here, it was found that not the defects created during ion implantation but the P doping itself results in the observed B diffusion retardation. The influence of the initial P concentration was investigated in more detail by varying the P implantation dose. A secondary ion mass spectrometry (SIMS) analysis of the BSG layer after the B diffusion revealed that the B diffusion retardation is not due to potential P content in the BSG layer but rather caused by the n-type doping of the crystalline silicon itself. Based on the observations the B diffusion retardation was classified into three groups: (i) no reduction of B diffusivity, (ii) reduced B diffusivity, and (iii) blocking of the B diffusion. The retardation of B diffusion can well be explained by the phosphorus doping level resulting in a Fermi level shift and pairing of B and P ions, both reducing the B diffusivity. Besides these main influences, there are probably additional transient phenomena responsible for the blocking of boron. Those might be an interstitial transport mechanism caused by P diffusion that reduces interstitial concentration at the surface or the silicon/BSG interface shift due to oxidation during the BBr3 diffusion process. Lifetime measurements revealed that the residual (non-blocked) B leads to an increased dark saturation current density in the P doped region. Nevertheless, electrical quality is on a high level and was further increased by reducing the B dose as well as by removing the first few nanometers of the silicon surface after the BBr3

  5. Impact of implanted phosphorus on the diffusivity of boron and its applicability to silicon solar cells

    SciTech Connect

    Schrof, Julian Müller, Ralph; Benick, Jan; Hermle, Martin; Reedy, Robert C.

    2015-07-28

    Boron diffusivity reduction in extrinsically doped silicon was investigated in the context of a process combination consisting of BBr{sub 3} furnace diffusion and preceding Phosphorus ion implantation. The implantation of Phosphorus leads to a substantial blocking of Boron during the subsequent Boron diffusion. First, the influences of ion implantation induced point defects as well as the initial P doping on B diffusivity were studied independently. Here, it was found that not the defects created during ion implantation but the P doping itself results in the observed B diffusion retardation. The influence of the initial P concentration was investigated in more detail by varying the P implantation dose. A secondary ion mass spectrometry (SIMS) analysis of the BSG layer after the B diffusion revealed that the B diffusion retardation is not due to potential P content in the BSG layer but rather caused by the n-type doping of the crystalline silicon itself. Based on the observations the B diffusion retardation was classified into three groups: (i) no reduction of B diffusivity, (ii) reduced B diffusivity, and (iii) blocking of the B diffusion. The retardation of B diffusion can well be explained by the phosphorus doping level resulting in a Fermi level shift and pairing of B and P ions, both reducing the B diffusivity. Besides these main influences, there are probably additional transient phenomena responsible for the blocking of boron. Those might be an interstitial transport mechanism caused by P diffusion that reduces interstitial concentration at the surface or the silicon/BSG interface shift due to oxidation during the BBr{sub 3} diffusion process. Lifetime measurements revealed that the residual (non-blocked) B leads to an increased dark saturation current density in the P doped region. Nevertheless, electrical quality is on a high level and was further increased by reducing the B dose as well as by removing the first few nanometers of the silicon surface after

  6. Impact of implanted phosphorus on the diffusivity of boron and its applicability to silicon solar cells

    SciTech Connect

    Schrof, Julian; Müller, Ralph; Reedy, Robert C.; Benick, Jan; Hermle, Martin

    2015-07-28

    Boron diffusivity reduction in extrinsically doped silicon was investigated in the context of a process combination consisting of BBr3 furnace diffusion and preceding Phosphorus ion implantation. The implantation of Phosphorus leads to a substantial blocking of Boron during the subsequent Boron diffusion. First, the influences of ion implantation induced point defects as well as the initial P doping on B diffusivity were studied independently. Here, it was found that not the defects created during ion implantation but the P doping itself results in the observed B diffusion retardation. The influence of the initial P concentration was investigated in more detail by varying the P implantation dose. A secondary ion mass spectrometry (SIMS) analysis of the BSG layer after the B diffusion revealed that the B diffusion retardation is not due to potential P content in the BSG layer but rather caused by the n-type doping of the crystalline silicon itself. Based on the observations the B diffusion retardation was classified into three groups: (i) no reduction of B diffusivity, (ii) reduced B diffusivity, and (iii) blocking of the B diffusion. The retardation of B diffusion can well be explained by the phosphorus doping level resulting in a Fermi level shift and pairing of B and P ions, both reducing the B diffusivity. Besides these main influences, there are probably additional transient phenomena responsible for the blocking of boron. Those might be an interstitial transport mechanism caused by P diffusion that reduces interstitial concentration at the surface or the silicon/BSG interface shift due to oxidation during the BBr3 diffusion process. Lifetime measurements revealed that the residual (non-blocked) B leads to an increased dark saturation current density in the P doped region. Nevertheless, electrical quality is on a high level and was further increased by reducing the B dose as well as by removing the first few nanometers of the silicon surface after the BBr3

  7. Does availability of informal care within the household impact hospitalisation?

    PubMed

    Weaver, France M; Weaver, Bryce A

    2014-01-01

    This study assesses the effect of having informal support available at home on inpatient care use in Switzerland. The main contributions are to consider the availability of care regardless of its source, measured by multiple-adult living arrangements, and to examine this effect by type of inpatient care and source of potential support. A two-part model with region and time fixed effects is estimated to determine the impact of informal care availability on the likelihood of hospitalisation and length of stay, conditional on hospitalisation. The analysis is conducted on a sample of individuals aged 18+ from four waves of the Swiss Household Panel survey (2004-2007). Overall, availability of informal care has no impact on the likelihood of hospitalisation but does significantly reduce length of stay by 1.9 days. Available support has no effect on the shortest stays (up to 10 days), but has a significant impact on acute care stays up to 30 days and longer stays. Additionally, the effect does not significantly vary whether the source of informal support is a spouse only, a spouse and other adults, or other adults only. These results indicate that social changes leading to an expansion in the proportion of one-person households may increase future inpatient care use.

  8. Impact of information technology on human resources in healthcare.

    PubMed

    Anvari, Mehran

    2007-01-01

    Incorporation of advances in information communications technology (ICT) into the workplace has had a major impact in human resource utilization in sectors of the economy where it has occurred in a substantial manner, such as manufacturing and financial services. While some benefits of ICT have been realized in healthcare, the full impact of its benefits will only be realized if it is incorporated in a systematic form, rather than in the current patchy and uneven manner seen around the province and across the country to date.

  9. The Impact of Diffuse Ionized Gas on Emission-line Ratios and Gas Metallicity Measurements

    NASA Astrophysics Data System (ADS)

    Zhang, Kai; Yan, Renbin; MaNGA Team

    2016-01-01

    Diffuse Ionized Gas (DIG) is prevalent in star-forming galaxies. Using a sample of galaxies observed by MaNGA, we demonstrate how DIG in star-forming galaxies impact the measurements of emission line ratios, hence the gas-phase metallicity measurements and the interpretation of diagnostic diagrams. We demonstrate that emission line surface brightness (SB) is a reasonably good proxy to separate HII regions from regions dominated by diffuse ionized gas. For spatially-adjacent regions or regions at the same radius, many line ratios change systematically with emission line surface brightness, reflecting a gradual increase of dominance by DIG towards low SB. DIG could significantly bias the measurement of gas metallicity and metallicity gradient. Because DIG tend to have a higher temperature than HII regions, at fixed metallicity DIG displays lower [NII]/[OII] ratios. DIG also show lower [OIII]/[OII] ratios than HII regions, due to extended partially-ionized regions that enhance all low-ionization lines ([NII], [SII], [OII], [OI]). The contamination by DIG is responsible for a substantial portion of the scatter in metallicity measurements. At different surface brightness, line ratios and line ratio gradients can differ systematically. As DIG fraction could change with radius, it can affect the metallicity gradient measurements in systematic ways. The three commonly used strong-line metallicity indicators, R23, [NII]/[OII], O3N2, are all affected in different ways. To make robust metallicity gradient measurements, one has to properly isolate HII regions and correct for DIG contamination. In line ratio diagnostic diagrams, contamination by DIG moves HII regions towards composite or LINER-like regions.

  10. Diffusion-weighted imaging of the abdomen: Impact of b-values on texture analysis features.

    PubMed

    Becker, Anton S; Wagner, Matthias W; Wurnig, Moritz C; Boss, Andreas

    2017-01-01

    The purpose of this work was to systematically assess the impact of the b-value on texture analysis in MR diffusion-weighted imaging (DWI) of the abdomen. In eight healthy male volunteers, echo-planar DWI sequences at 16 b-values ranging between 0 and 1000 s/mm(2) were acquired at 3 T. Three different apparent diffusion coefficient (ADC) maps were computed (0, 750/100, 390, 750 s/mm(2) /all b-values). Texture analysis of rectangular regions of interest in the liver, kidney, spleen, pancreas, paraspinal muscle and subcutaneous fat was performed on DW images and the ADC maps, applying 19 features computed from the histogram, grey-level co-occurrence matrix (GLCM) and grey-level run-length matrix (GLRLM). Correlations between b-values and texture features were tested with a linear and an exponential model; the best fit was determined by the smallest sum of squared residuals. Differences between the ADC maps were assessed with an analysis of variance. A Bonferroni-corrected p-value less than 0.008 (=0.05/6) was considered statistically significant. Most GLCM and GLRLM-derived texture features (12-18 per organ) showed significant correlations with the b-value. Four texture features correlated significantly with changing b-values in all organs (p < 0.008). Correlation coefficients varied between 0.7 and 1.0. The best fit varied across different structures, with fat exhibiting mostly exponential (17 features), muscle mostly linear (12 features) and the parenchymatous organs mixed feature alterations. Two GLCM features showed significant variability in the different ADC maps. Several texture features vary systematically in healthy tissues at different b-values, which needs to be taken into account if DWI data with different b-values are analyzed. Histogram and GLRLM-derived texture features are stable on ADC maps computed from different b-values.

  11. Impact of Healthcare Information Technology on Nursing Practice.

    PubMed

    Piscotty, Ronald J; Kalisch, Beatrice; Gracey-Thomas, Angel

    2015-07-01

    To report additional mediation findings from a descriptive cross sectional study to examine if nurses' perceptions of the impact of healthcare information technology on their practice mediates the relationship between electronic nursing care reminder use and missed nursing care. The study used a descriptive design. The sample (N = 165) was composed of registered nurses working on acute care hospital units. The sample was obtained from a large teaching hospital in Southeast Michigan in the fall of 2012. All eligible nursing units (n = 19) were included. The MISSCARE Survey, Nursing Care Reminders Usage Survey, and the Impact of Healthcare Information Technology Scale were used to collect data to test for mediation. Mediation was tested using the method described by Baron and Kenny. Multiple regression equations were used to analyze the data to determine if mediation occurred between the variables. Missed nursing care, the outcome variable, was regressed on the predictor variable, reminder usage, and the mediator variable impact of technology on nursing practice. The impact of healthcare information technology (IHIT) on nursing practice negatively affected missed nursing care (t = -4.12, p < .001), explaining 9.8% of variance in missed nursing care. With IHIT present, the predictor (reminder usage) was no longer significant (t = -.70, p = .48). Thus, the reduced direct association between reminder usage and missed nursing care when IHIT was in the model supported the hypothesis that IHIT was at least one of the mediators in the relationship between reminder usage and missed nursing care. The perceptions of the impact of healthcare information technology mediates the relationship between nursing care reminder use and missed nursing care. The findings are beneficial to the advancement of healthcare technology in that designers of healthcare information technology systems need to keep in mind that perceptions regarding impacts of the technology will influence usage

  12. Impact of Training Bolivian Farmers on Integrated Pest Management and Diffusion of Knowledge to Neighboring Farmers.

    PubMed

    Jørs, Erik; Konradsen, Flemming; Huici, Omar; Morant, Rafael C; Volk, Julie; Lander, Flemming

    2016-01-01

    Teaching farmers integrated pest management (IPM) in farmer field schools (FFS) has led to reduced pesticide use and safer handling. This article evaluates the long-term impact of training farmers on IPM and the diffusion of knowledge from trained farmers to neighboring farmers, a subject of importance to justify training costs and to promote a healthy and sustainable agriculture. Training on IPM of farmers took place from 2002 to 2004 in their villages in La Paz County, Bolivia, whereas dissemination of knowledge from trained farmer to neighboring farmer took place until 2009. To evaluate the impact of the intervention, self-reported knowledge and practice on pesticide handling and IPM among trained farmers (n = 23) and their neighboring farmers (n = 47) were analyzed in a follow-up study and compared in a cross-sectional analysis with a control group of farmers (n = 138) introduced in 2009. Variables were analyzed using χ2 test and analysis of variance (ANOVA). Trained farmers improved and performed significantly better in all tested variables than their neighboring farmers, although the latter also improved their performance from 2002 to 2009. Including a control group showed an increasing trend in all variables, with the control farmers having the poorest performance and trained farmers the best. The same was seen in an aggregated variable where trained farmers had a mean score of 16.55 (95% confidence interval [CI]: 15.45-17.65), neighboring farmers a mean score of 11.97 (95% CI: 10.56-13.38), and control farmers a mean score of 9.18 (95% CI: 8.55-9.80). Controlling for age and living altitude did not change these results. Trained farmers and their neighboring farmers improved and maintained knowledge and practice on IPM and pesticide handling. Diffusion of knowledge from trained farmers might explain the better performance of the neighboring farmers compared with the control farmers. Dissemination of knowledge can contribute to justify the cost and convince

  13. Impact of compression on gas transport in non-woven gas diffusion layers of high temperature polymer electrolyte fuel cells

    NASA Astrophysics Data System (ADS)

    Froning, Dieter; Yu, Junliang; Gaiselmann, Gerd; Reimer, Uwe; Manke, Ingo; Schmidt, Volker; Lehnert, Werner

    2016-06-01

    Gas transport in non-woven gas diffusion layers of a high-temperature polymer electrolyte fuel cell was calculated with the Lattice Boltzmann method. The underlying micro structure was taken from two sources. A real micro structure was analyzed in the synchrotron under the impact of a compression mask mimicking the channel/rib structure of a flow field. Furthermore a stochastic geometry model based on synchrotron X-ray tomography studies was applied. The effect of compression is included in the stochastic model. Gas transport in these micro structures was simulated and the impact of compression was analyzed. Fiber bundles overlaying the micro structure were identified which affect the homogeneity of the gas flow. There are significant deviations between the impact of compression on effective material properties for this type of gas diffusion layers and the Kozeny-Carman equation.

  14. The Performance of Direct Disk Diffusion for Community Acquired Bacteremia due to Gram-Negative Bacilli and Its Impact on Physician Treatment Decisions

    PubMed Central

    Daley, Peter; Comerford, Adam; Umali, Jurgienne; Penney, Carla

    2016-01-01

    Background. Direct disk diffusion susceptibility testing provides faster results than standard microtitre susceptibility. The direct result may impact patient outcome in sepsis if it is accurate and if physicians use the information to promptly and appropriately change antibiotic treatment. Objective. To compare the performance of direct disk diffusion with standard susceptibility and to consider physician decisions in response to these early results, for community acquired bacteremia with Gram-negative Bacilli. Methods. Retrospective observational study of all positive blood cultures with Gram-negative Bacilli, collected over one year. Physician antibiotic treatment decisions were assessed by an infectious diseases physician based on information available to the physician at the time of the decision. Results. 89 bottles growing Gram-negative Bacilli were included in the analysis. Direct disk diffusion agreement with standard susceptibility varied widely. In 47 cases (52.8%), the physician should have changed to a narrower spectrum but did not, in 18 cases (20.2%), the physician correctly narrowed from appropriate broad coverage, and in 8 cases (9.0%), the empiric therapy was correct. Discussion. Because inoculum is not standardized, direct susceptibility results do not agree with standard susceptibility results for all drugs. Physicians do not act on direct susceptibility results. Conclusion. Direct susceptibility should be discontinued in clinical microbiology laboratories. PMID:27366172

  15. The Performance of Direct Disk Diffusion for Community Acquired Bacteremia due to Gram-Negative Bacilli and Its Impact on Physician Treatment Decisions.

    PubMed

    Daley, Peter; Comerford, Adam; Umali, Jurgienne; Penney, Carla

    2016-01-01

    Background. Direct disk diffusion susceptibility testing provides faster results than standard microtitre susceptibility. The direct result may impact patient outcome in sepsis if it is accurate and if physicians use the information to promptly and appropriately change antibiotic treatment. Objective. To compare the performance of direct disk diffusion with standard susceptibility and to consider physician decisions in response to these early results, for community acquired bacteremia with Gram-negative Bacilli. Methods. Retrospective observational study of all positive blood cultures with Gram-negative Bacilli, collected over one year. Physician antibiotic treatment decisions were assessed by an infectious diseases physician based on information available to the physician at the time of the decision. Results. 89 bottles growing Gram-negative Bacilli were included in the analysis. Direct disk diffusion agreement with standard susceptibility varied widely. In 47 cases (52.8%), the physician should have changed to a narrower spectrum but did not, in 18 cases (20.2%), the physician correctly narrowed from appropriate broad coverage, and in 8 cases (9.0%), the empiric therapy was correct. Discussion. Because inoculum is not standardized, direct susceptibility results do not agree with standard susceptibility results for all drugs. Physicians do not act on direct susceptibility results. Conclusion. Direct susceptibility should be discontinued in clinical microbiology laboratories.

  16. [Impact of diffusion of the methodology of evidence-based nursing through Facebook].

    PubMed

    Santillán García, Azucena

    2013-05-01

    Evaluate the impact of diffusion of the contents of the blog "Evidence-Based Nursing" through Facebook. Cross-sectional study carried out via a web link to the online survey (previously tested) to a population of 2132 Facebook profiles that had a "friendship" with the profile studied. The survey had 8 items and a descriptive study of variables was conducted using SPSS 19. 75.9% of the sample has a Facebook profile of a personal character and 94.1% of cases are interested in evidence-based practices. 55.6% of the sample knows the blog, plus 46.5% answered that they read it occasionally, compared with 17.1% who does regularly and 35.7% who say they do not read it. Of all readers, 75.75% say they have improved their knowledge in terms of evidence-based practice after reading it. 88% said they did not follow the blog by other means or social network and in the case that they did, the most used are Google Reader, and Twitter Networked Blogs. Reading the contents of this blog improve the knowledge about evidence-based practices of the "friends" of the social profile, as they themselves relate. The adequacy of the social profile as a dissemination tool is successful as it is necessary to investigate in depth the functioning of social networks.

  17. Charpy impact test of Ti-6Al-4V joints diffusion welded at low temperature

    SciTech Connect

    Salazar, J.M.G. de; Urena, A.; Carrion, J.G.

    1996-08-15

    The Diffusion Welding (DW) of two or more sheets of Ti-6Al-4V alloy is particularly interesting for aerospace parts manufacturing. In some cases, DW can be carried out together with Superplastic Forming (SPF), because they can share a single facility and the same processing parameters, such as temperature, pressure, time, surface condition and vacuum. The overall manufacturing process is known as SPF/DW, by which it is possible to obtain honeycomb structures in a range of designs. Temperature requirements for industrial SPF of Ti-6Al-4V are very restrictive and a temperature of 1,023 K is needed. However, temperature is not so critical for DW, and the bond can be produced at lower temperatures, when other DW parameters, mainly pressure and time, are changed in a suitable way. The DW parameters for this research were chosen in order to produce DW joints below 1,023 K. The differences between DW at SPF temperatures and other lower temperatures would thus be revealed. Mechanical tests were used as a tool to check DW joints obtained at the temperatures used in the research (1,123 K and 1,023 K), and were complemented with metallographic studies. The results obtained form shear and peel tests have been already discussed. In the present work the results of impact energy tests are also presented.

  18. Diffuse nutrient losses and the impact factors determining their regional differences in four catchments from North to South China

    NASA Astrophysics Data System (ADS)

    Zhang, Yongyong; Zhou, Yujian; Shao, Quanxi; Liu, Hongbin; Lei, Qiuliang; Zhai, Xiaoyan; Wang, Xuelei

    2016-12-01

    Diffuse nutrient loss mechanism is complicated and shows remarkably regional differences due to spatial heterogeneities of underlying surface conditions, climate and agricultural practices. Moreover, current available observations are still hard to support the identification of impact factors due to different time or space steps. In this study, an integrated water system model (HEQM) was adopted to obtain the simulated loads of diffuse components (carriers: runoff and sediment; nutrient: total nitrogen (TN) and total phosphorous (TP)) with synchronous scales. Multivariable statistical analysis approaches (Analysis of Similarity and redundancy analysis) were used to assess the regional differences, and to identify impact factors as well as their contributions. Four catchments were selected as our study areas, i.e., Xiahui and Zhangjiafen Catchments of Miyun Basin in North China, Yuliang and Tunxi Catchments of Xin'anjiang Basin in South China. Results showed that the model performances of monthly processes were very good for runoff and good for sediment, TN and TP. The annual average coefficients of all the diffuse components in Xin'anjiang Basin were much greater than those in Miyun Basin, and showed significantly regional differences. All the selected impact factors interpreted 72.87-82.16% of the regional differences of carriers, and 62.72-71.62% of those of nutrient coefficients, respectively. For individual impact factor categories, the critical category was geography, followed by land-use/cover, carriers, climate, as well as soil and agricultural practices in Miyun Basin, or agricultural practices and soil in Xin'anjiang Basin. For individual factors, the critical factors were locations for the carrier regional differences, and carriers or chemical fertilizer for the nutrient regional differences. This study is expected to promote further applications of integrated water system model and multivariable statistical analysis in the diffuse nutrient studies, and

  19. Impact of Thailand universal coverage scheme on the country's health information systems and health information technology.

    PubMed

    Kijsanayotin, Boonchai

    2013-01-01

    Thailand achieved universal healthcare coverage with the implementation of the Universal Coverage Scheme (UCS) in 2001. This study employed qualitative method to explore the impact of the UCS on the country's health information systems (HIS) and health information technology (HIT) development. The results show that health insurance beneficiary registration system helps improve providers' service workflow and country vital statistics. Implementation of casemix financing tool, Thai Diagnosis-Related Groups, has stimulated health providers' HIS and HIT capacity building, data and medical record quality and the adoption of national administrative data standards. The system called "Disease Management Information Systems" aiming at reimbursement for select diseases increased the fragmentation of HIS and increase burden on data management to providers. The financial incentive of outpatient data quality improvement project enhance providers' HIS and HIT investment and also induce data fraudulence tendency. Implementation of UCS has largely brought favorable impact on the country HIS and HIT development. However, the unfavorable effects are also evident.

  20. Impacting university physics students through participation in informal science

    NASA Astrophysics Data System (ADS)

    Hinko, Kathleen; Finkelstein, Noah D.

    2013-01-01

    Informal education programs organized by university physics departments are a popular means of reaching out to communities and satisfying grant requirements. The outcomes of these programs are often described in terms of broader impacts on the community. Comparatively little attention, however, has been paid to the influence of such programs on those students facilitating the informal science programs. Through Partnerships for Informal Science Education in the Community (PISEC) at the University of Colorado Boulder, undergraduate and graduate physics students coach elementary and middle school children during an inquiry-based science afterschool program. As part of their participation in PISEC, university students complete preparation in pedagogy, communication and diversity, engage with children on a weekly basis and provide regular feedback about the program. We present findings that indicate these experiences improve the ability of university students to communicate in everyday language and positively influence their perspectives on teaching and learning.

  1. Approach to asymptotically diffusive behavior for Brownian particles in periodic potentials: Extracting information from transients

    NASA Astrophysics Data System (ADS)

    Dean, David S.; Oshanin, Gleb

    2014-08-01

    A Langevin process describing diffusion in a periodic potential landscape has a time-dependent diffusion constant, which means that its average mean-squared displacement (MSD) only becomes linear at late times. The long-time, or effective diffusion, constant can be estimated from the slope of a linear fit of the MSD at late times. Due to the crossover between a short time microscopic diffusion constant, which is independent of the potential, to the effective late-time diffusion constant, a linear fit of the MSD will not in general pass through the origin and will have a nonzero constant term. Here we address how to compute the constant term and provide explicit results for Brownian particles in one dimension in periodic potentials. We show that the constant is always positive and that at low temperatures it depends on the curvature of the minimum of the potential. For comparison we also consider the same question for the simpler problem of a symmetric continuous time random walk in discrete space. Here the constant can be positive or negative and can be used to determine the variance of the hopping time distribution.

  2. Surface diffusion of molecular glasses: Material dependence and impact on physical stability

    NASA Astrophysics Data System (ADS)

    Ruan, Shigang; Zhang, Wei; Yu, Lian

    Surface diffusion coefficients have been measured for molecular glasses tris-naphthylbenzene (TNB) and PMMA oligomers by surface grating decay. Surface diffusion on TNB is vastly faster than bulk diffusion, by a factor of 107 at Tg, while the process is very slow on PMMA. Along with the previous results on o - terphenyl, nifedipine, indomethacin, and polystyrene oligomers, we find that surface diffusion slows down with increasing molecular size and intermolecular forces, whereas bulk diffusion has a weaker material dependence. The molecular glasses studied show fast crystal growth on the free surface. A general correlation is observed between the coefficient of surface diffusion and the velocity of surface crystal growth, indicating surface crystallization is supported by surface mobility. (Zhu, L., et al. Phys. Rev. Lett. 106 (2011): 256103; Zhang, W., et al. J. Phys. Chem. B 119 (2015): 5071-5078) Nsf.

  3. Complete Separation of Intracellular and Extracellular Information in NMR Spectra of Perfused Cells by Diffusion-Weighted Spectroscopy

    NASA Astrophysics Data System (ADS)

    van Zijl, Peter C. M.; Moonen, Chrit T. W.; Faustino, Patrick; Pekar, James; Kaplan, Ofer; Cohen, Jack S.

    1991-04-01

    A method is outlined that completely separates intracellular and extracellular information in NMR spectra of perfused cells. The technique uses diffusion weighting to exploit differences in motional properties between intra- and extracellular constituents. This allows monitoring of intracellular metabolism, and of transport of small drugs and nutrients through the cell membrane, under controlled physiological conditions. As a first example, proton spectra of drug-resistant MCF-7 human breast cancer cells are studied, and uptake of phenylalanine is monitored.

  4. NASA/DOD Aerospace Knowledge Diffusion Research Project. Report number 21: US aerospace industry librarians and technical information specialists as information intermediaries: Results of the phase 2 survey

    NASA Technical Reports Server (NTRS)

    Pinelli, Thomas E.; Barclay, Rebecca O.; Kennedy, John M.

    1994-01-01

    The U.S. government technical report is a primary means by which the results of federally funded research and development (R&D) are transferred to the U.S. aerospace industry. However, little is known about this information product in terms of its actual use, importance, and value in the transfer of federally funded R&D. To help establish a body of knowledge, the U.S. government technical report is being investigated as part of the NASA/DoD Aerospace Knowledge Diffusion Research Project. In this report, we summarize the literature on technical reports and provide a model that depicts the transfer of federally funded aerospace R&D via the U.S. government technical report. We present results from our investigation of aerospace knowledge diffusion vis-a-vis the U.S. government technical report, and present the results of research that investigated aerospace knowledge diffusion vis-a-vis U.S. aerospace industry librarians and technical information specialists as information intermediaries.

  5. NASA/DOD Aerospace Knowledge Diffusion Research Project. Report 22: US academic librarians and technical information specialists as information intermediaries: Results of the phase 3 survey

    NASA Technical Reports Server (NTRS)

    Pinelli, Thomas E.; Barclay, Rebecca O.; Kennedy, John M.

    1994-01-01

    The U.S. government technical report is a primary means by which the results of federally funded research and development (R&D) are transferred to the U.S. aerospace industry. However, little is known about this information product in terms of its actual use, importance, and value in the transfer of federally funded R&D. To help establish a body of knowledge, the U.S. government technical report is being investigated as part of the NASA/DOD Aerospace Knowledge Diffusion Research Project. In this report, we summarize the literature on technical reports and provide a model that depicts the transfer of federally funded aerospace R&D via the U.S. government technical report. We present results from our investigation of aerospace knowledge diffusion vis-a-vis the U.S. government technical report, and present the results of research that investigated aerospace knowledge diffusion vis-a-vis U.S. academic librarians and technical information specialists as information intermediaries.

  6. Professional and organizational impact of using patient care information systems.

    PubMed

    Hebert, M

    1998-01-01

    Evaluation of information systems has often been limited to success factors in relation to system implementation (on time and on budget), training and use of the system. Little attention has been paid to the longer-term effect of using these systems and the resulting issues for health care professionals and organizations. This paper reports on a multiple case study of community hospitals, which examined the impact of using Patient Care Information Systems. An analytic framework incorporated Donabedian's 3 aspects of quality care: structure, process and outcome. These were examined at three levels of impact; direct substitution, proceduralization and new capabilities. Many of the anticipated benefits in the study did not occur because changes occurring in structure (generally taks done by pharmacists and laboratory technologists) did not automatically influence process changes (such as decision making of physicians and nurses) or patient outcomes. Four themes illustrate important professional and organizational issues with implications for worklife of professionals, management and career training. They include the effects of increased efficiency and productivity; "visible" accountability; changing roles and responsibilities; and learning to use new technology versus using new information.

  7. Cross-modal impacts of anthropogenic noise on information use.

    PubMed

    Morris-Drake, Amy; Kern, Julie M; Radford, Andrew N

    2016-10-24

    Anthropogenic noise is a global pollutant, and there is rapidly accumulating evidence of impacts on a range of animal taxa [1,2]. While many studies have considered how additional noise may affect information provision and use, they have focused on the masking and consequent alteration of acoustic signals and cues; so-called unimodal effects [3]. Using field-based experimental trials on habituated wild dwarf mongooses (Helogale parvula) [4], we combine sound playbacks and faecal presentations to demonstrate that anthropogenic noise can disrupt responses to information from different sensory modalities. The adaptive, stronger response exhibited towards predator faeces compared with control faeces in ambient-noise conditions was detrimentally affected by road-noise playback. Specifically, having taken longer to detect the faeces, the mongooses interacted less with the predator cue, did not show increased vigilance following its detection, and spent less time in the safe vicinity of a burrow refuge, thus suffering a potentially increased predation risk. Our results are the first to show that anthropogenic noise could alter responses to olfactory cues, strongly indicating the possibility of cross-modal impacts of noise pollution on information use [3]. Crown Copyright © 2016. Published by Elsevier Ltd. All rights reserved.

  8. Information to help reduce environmental impacts from freshwater oil spills

    SciTech Connect

    Fritz, D.E.; Steen, A.E.

    1995-12-31

    The American Petroleum Institute (API) has been working since 1990 to provide information to help the response community minimize the impact of spills to pared jointly with the US inland freshwater. Projects have included a manual, pre National Oceanic and Atmospheric Administration (NOAA), to give guidance on the cleanup techniques that will minimize environmental impacts on spills in freshwater habitats. Nearing completion are a literature review and annotated bibliography of the environmental and human health effects of oil spilled in freshwater habitats. The use of chemical treating agents for freshwater spill applications is being studied with input from other industry and government groups. A project has begun, with funding from API, the Louisiana Applied Oil Spill Research and Development Program, NOAA, the Marine Spill Response Corporation (MSRC), and the US Department of Energy, to evaluate in situ burning of oil spilled in marshes.

  9. Beyond Economy: Impact of National Cultural Values on Nationwide Broadband Internet Diffusion

    ERIC Educational Resources Information Center

    Joo, Sung-Hee

    2010-01-01

    This study examines how the non-conventional factors of national cultural values and government involvement affect the diffusion of broadband Internet technologies in various nations around the world. An innovative element of the study was the examination of the influence patterns at different stages of diffusion, which was measured by the number…

  10. Beyond Economy: Impact of National Cultural Values on Nationwide Broadband Internet Diffusion

    ERIC Educational Resources Information Center

    Joo, Sung-Hee

    2010-01-01

    This study examines how the non-conventional factors of national cultural values and government involvement affect the diffusion of broadband Internet technologies in various nations around the world. An innovative element of the study was the examination of the influence patterns at different stages of diffusion, which was measured by the number…

  11. Evaluation of the impact of atmospheric ozone and aerosols on the horizontal global/diffuse UV Index at Livorno (Italy)

    NASA Astrophysics Data System (ADS)

    Scaglione, Daniele; Giulietti, Danilo; Morelli, Marco

    2016-08-01

    A study was conducted at Livorno (Italy) to evaluate the impact of atmospheric aerosols and ozone on the solar UV radiation and its diffuse component at ground in clear sky conditions. Solar UV radiation has been quantified in terms of UV Index (UVI), following the ISO 17166:1999/CIE S007/E-1998 international standard. UVI has been calculated by exploiting the libRadtran radiative transfer modelling software as a function of both the Aerosols Optical Depth (AOD) and the Total Ozone Column (TOC). In particular AOD and TOC values have been remotely sensed by the Ozone Monitoring Instrument (OMI) on board the NASA's EOS (Earth Observing System) satellites constellation. An experimental confirmation was also obtained by exploiting global UVI ground-based measurements from the 26/9/14 to 12/8/15 and diffuse UVI ground-based measurements from the 17/5/15 to 12/8/15. For every considered value of Solar Zenith Angle (SZA) and atmospheric condition, estimates and measurements confirm that the diffuse component contributes for more than 50% on the global UV radiation. Therefore an exposure of human skin also to diffuse solar UV radiation can be potentially harmful for health and need to be accurately monitored, e.g. by exploiting innovative applications such as a mobile app with a satellite-based UV dosimeter that has been developed. Global and diffuse UVI variations due to the atmosphere are primarily caused by the TOC variations (typically cyclic): the maximum TOC variation detected by OMI in the area under study leads to a corresponding variation in global and diffuse UVI of about 50%. Aerosols in the area concerned, mainly of maritime nature, have instead weaker effects causing a maximum variation of the global and diffuse UVI respectively of 9% and 35% with an SZA of 20° and respectively of 13% and 10% with an SZA of 60°.

  12. Determination of partition and diffusion coefficients of formaldehyde in selected building materials and impact of relative humidity.

    PubMed

    Xu, Jing; Zhang, Jianshun S; Liu, Xiaoyu; Gao, Zhi

    2012-06-01

    The partition and effective diffusion coefficients of formaldehyde were measured for three materials (conventional gypsum wallboard, "green" gypsum wallboard, and "green" carpet) under three relative humidity (RH) conditions (20%, 50%, and 70% RH). The "green" materials contained recycled materials and were friendly to environment. A dynamic dual-chamber test method was used. Results showed that a higher relative humidity led to a larger effective diffusion coefficient for two kinds of wallboards and carpet. The carpet was also found to be very permeable resulting in an effective diffusion coefficient at the same order of magnitude with the formaldehyde diffusion coefficient in air. The partition coefficient (K(ma)) of formaldehyde in conventional wallboard was 1.52 times larger at 50% RH than at 20% RH, whereas it decreased slightly from 50% to 70% RH, presumably due to the combined effects of water solubility of formaldehyde and micro-pore blocking by condensed moisture at the high RH level. The partition coefficient of formaldehyde increased slightly with the increase of relative humidity in "green" wallboard and "green" carpet. At the same relative humidity level, the "green" wallboard had larger partition coefficient and effective diffusion coefficient than the conventional wallboard, presumably due to the micro-pore structure differences between the two materials. The data generated could be used to assess the sorption effects of formaldehyde on building materials and to evaluate its impact on the formaldehyde concentration in buildings.

  13. Characterization of lipid model membranes designed for studying impact of ceramide species on drug diffusion and penetration.

    PubMed

    Ochalek, M; Heissler, S; Wohlrab, J; Neubert, R H H

    2012-05-01

    The stratum corneum (SC) intercellular lipid matrix plays a crucial role in the skin barrier function. In the present study, lipid model membranes mimicking its phase behavior were prepared and characterized using different analytical techniques (i.a. SAXD, HPTLC, ESEM, confocal Raman imaging, ATR-FTIR spectroscopy) in order to obtain well-standardized model membranes for diffusion and penetration studies. The lipid model membranes should be used in the future for studying the impact of each ceramide species on the diffusion and penetration of drugs. The SAXD study confirmed that the lipids within artificial lipid systems are arranged similarly to the lipids in the human SC. The polarization microscopic and ESEM images showed the homogenous deposition of lipids on the polycarbonate filter. Both the HPTLC and confocal Raman imaging studies proved the homogenous distribution of individual lipid classes within the lipid model membranes. First in vitro diffusion experiments (performed using an ATR-FTIR diffusion cell) of the hydrophilic compound, urea, revealed that the lipid model membrane represents even stronger diffusion barrier than the human SC. Copyright © 2012 Elsevier B.V. All rights reserved.

  14. Innovation Value of Information Technology: Impact of Information Technology--Intensity on Innovation Capability and Firm Performance

    ERIC Educational Resources Information Center

    Ramamani, Mahesh Kumar

    2010-01-01

    Though information technology adoptions have been always referred to as innovations in firms, much of the business value literature has concentrated on the tangible and immediately measurable impacts of information technology (IT) adoptions. This study aims to explore the impact of information technology investments on the innovativeness of a…

  15. Innovation Value of Information Technology: Impact of Information Technology--Intensity on Innovation Capability and Firm Performance

    ERIC Educational Resources Information Center

    Ramamani, Mahesh Kumar

    2010-01-01

    Though information technology adoptions have been always referred to as innovations in firms, much of the business value literature has concentrated on the tangible and immediately measurable impacts of information technology (IT) adoptions. This study aims to explore the impact of information technology investments on the innovativeness of a…

  16. The ADS in the Information Age - Impact on Discovery

    NASA Astrophysics Data System (ADS)

    Henneken, Edwin A.; Kurtz, Michael J.; Accomazzi, Alberto

    2012-08-01

    The SAO/NASA Astrophysics Data System (ADS) grew up with and has been riding the waves of the Information Age, closely monitoring and anticipating the needs of its end-users. By now, all professional astronomers are using the ADS on a daily basis, and a substantial fraction have been using it for their entire professional career. In addition to being an indispensable tool for professional scientists, the ADS also moved into the public domain, as a tool for science education. In this paper we will highlight and discuss some aspects indicative of the impact the ADS has had on research and the access to scholarly publications.

  17. Prognostic impact of C-REL expression in diffuse large B-cell lymphoma.

    PubMed

    Curry, Choladda V; Ewton, April A; Olsen, Randall J; Logan, Brent R; Preti, Hector A; Liu, Yao-Chang; Perkins, Sherrie L; Chang, Chung-Che

    2009-03-01

    Diffuse large B-cell lymphoma (DLBCL) with a germinal center B-cell (GCB) phenotype is believed to confer a better prognosis than DLBCL with an activated B-cell (ABC) phenotype. Previous studies have suggested that nuclear factor-kappaB (NF-kappaB) activation plays an important role in the ABC subtype of DLBCL, whereas c-REL amplification is associated with the GCB subtype. Using immunohistochemical techniques, we examined 68 newly diagnosed de novo DLBCL cases (median follow-up 44 months, range 1 to 142 months) for the expression of c-REL, BCL-6, CD10, and MUM1/IRF4. Forty-four (65%) cases demonstrated positive c-REL nuclear expression. In this cohort of patients, the GCB phenotype was associated with a better overall survival (OS) than the non-GCB phenotype (Kaplan-Meier survival (KMS) analysis, p = 0.016, Breslow-Gehan-Wilcoxon test). In general, c-REL nuclear expression did not correlate with GCB vs. non-GCB phenotype, International Prognostic Index score, or OS. However, cases with a GCB phenotype and negative nuclear c-REL demonstrated better OS than cases with a GCB phenotype and positive nuclear c-REL (KMS analysis, p = 0.045, Breslow-Gehan-Wilcoxon test), whereas in cases with non-GCB phenotype, the expression of c-REL did not significantly impact the prognosis. These results suggest that c-REL nuclear expression may be a prognostic factor in DLBCL and it may improve patient risk stratification in combination with GCB/non-GCB phenotyping.

  18. Social impacts of technological diffusion: prenatal diagnosis and induced abortion in Brazil.

    PubMed

    Novaes, H M

    2000-01-01

    Scientific and technological development plays an essential part in shaping contemporary societies, and medicine and health care are considered to be particularly receptive to the incorporation of new concepts, techniques and products, producing impacts not only on the health problems for which they were originally intended, but also varied 'side-effects', less frequently recognised and studied. In this study the point of departure was the hypothesis that the intensive diffusion in Brazil of prenatal ultrasound would create new problems for individuals (pregnant women, their families and health professionals) and society in coping with foetal malformations, due to the existence of a very restrictive induced abortion legislation. The objective of the research was to study the social visibility of these problems, in the written mass media. The period under analysis went from 1991 to 1996. The four most important daily newspapers and two medical council journals were studied, with a criteria oriented selection of articles, and their macrotextual thematic analysis. The results indicate that the basic elements in the relationships between medical technology, prenatal diagnosis, foetal malformations and induced abortions stayed the same along the period - a restrictive Penal Code, the public recognition of the disseminated and usually tolerated practice of induced abortion, done in risky conditions for the majority of women, with very evident consequences on maternal health, a divided Congress, a divided 'public opinion', religious opposition and new scientific and technological practices in health care. Nevertheless, tension between these 'contradictory' factors increases, so much so, that new elements are introduced which make an accommodation possible, without implying in major changes of position. This is achieved through the development of new alliances between Science, the judiciary and obstetrical leaders, which benefit individual initiatives, instead of leading

  19. Effect of dissolved oxygen manipulation on diffusive emissions from NAPL-impacted low permeability soil layers.

    PubMed

    Clifton, Lisa M; Dahlen, Paul R; Johnson, Paul C

    2014-05-06

    Aquifer physical model experiments were performed to investigate if diffusive emissions from nonaqueous phase liquid (NAPL)-impacted low-permeability layers into groundwater moving through adjacent NAPL-free high-permeability layers can be reduced by creating an aerobic biotreatment zone at the interface between the two, and if over time that leads to reduced emissions after treatment ceases. Experiments were performed in two 1.2-m long × 1.2-m high × 5.4 cm wide stainless steel tanks; each with a high-permeability sand layer overlying a low-permeability crushed granite layer containing a NAPL mixture of indane and benzene. Each tank was water-saturated with horizontal flow primarily through the sand layer. The influent water was initially deoxygenated and the emissions and concentration distributions were allowed to reach near-steady conditions. The influent dissolved oxygen (DO) level was increased stepwise to 6.5-8.5 mg/L and 17-20 mg/L, and then decreased back to deoxygenated conditions. Each condition was maintained for at least 45 days. Relative to the near-steady benzene emission at the initial deoxygenated condition, the emission was reduced by about 70% when the DO was 6.5-8.5 mg/L, 90% when the DO was 17-20 mg/L, and ultimately 60% when returning to low DO conditions. While the reductions were substantial during treatment, longer-term reductions after 120 d of elevated DO treatment, relative to an untreated condition predicted by theory, were low: 29% and 6% in Tank 1 and Tank 2, respectively. Results show a 1-2 month lag between the end of DO delivery and rebound to the final near-steady emissions level. This observation has implications for post-treatment performance monitoring sampling at field sites.

  20. Spectral Resolution and Coverage Impact on Advanced Sounder Information Content

    NASA Technical Reports Server (NTRS)

    Larar, Allen M.; Liu, Xu; Zhou, Daniel K.; Smith, William L.

    2010-01-01

    Advanced satellite sensors are tasked with improving global measurements of the Earth s atmosphere, clouds, and surface to enable enhancements in weather prediction, climate monitoring capability, and environmental change detection. Achieving such measurement improvements requires instrument system advancements. This presentation focuses on the impact of spectral resolution and coverage changes on remote sensing system information content, with a specific emphasis on thermodynamic state and trace species variables obtainable from advanced atmospheric sounders such as the Infrared Atmospheric Sounding Interferometer (IASI) and Cross-track Infrared Sounder (CrIS) systems on the MetOp and NPP/NPOESS series of satellites. Key words: remote sensing, advanced sounders, information content, IASI, CrIS

  1. China Refrigerator Information Label: Specification Development and Potential Impact

    SciTech Connect

    Fridley, David; Fridley, David; Zheng, Nina; Zhou, Nan; Aden, Nathaniel; Lin, Jiang; Jianhong, Cheng; Sakamoto, Tomoyuki

    2008-02-01

    In the last five years, China's refrigerator market has grown rapidly, and now urban markets are showing signs of saturation, with ownership rates in urban households reaching 92%. Rural markets continue to grow from a much lower base. As a result of this growth, the Chinese government in 2006 decided to revise the refrigerator standards and its associated efficiency grades for the mandatory energy information label. In the Chinese standards process, the efficiency grades for the information label are tied to the minimum standards. Work on the minimum standards revision began in 2006 and continued through the first half of 2007, when the draft standard was completed under the direction of the China National Institute of Standardization (CNIS). Development of the information label grades required consideration of stakeholder input, continuity with the previous grade classification, ease of implementation, and potential impacts on the market. In this process, CLASP, with the support of METI/IEEJ, collaborated with CNIS to develop the efficiency grades, providing technical input to the process, comment and advice on particular technical issues, and evaluation of the results. After three months of effort and three drafts of the final grade specifications, this work was completed. In addition, in order to effectively evaluate the impact of the label on China's market, CLASP further provided assistance to CNIS to collect data on both the efficiency distribution and product volume distribution of refrigerators on the market. The new information label thresholds to be implemented in 2008 maintain the approach first adopted in 2005 of establishing efficiency levels relative to the minimum standard, but increased the related required efficiency levels by 20% over those established in 2003 and implemented in 2005. The focus of improvement was on the standard refrigerator/freezer (class 5), which constitutes the bulk of the Chinese market. Indeed, the new requirements to

  2. The Impact of Information on Doctors' Attitudes Toward Generic Drugs.

    PubMed

    Tsaprantzi, Aggeliki V; Kostagiolas, Petros; Platis, Charalampos; Aggelidis, Vassilios P; Niakas, Dimitris

    2016-01-01

    The objective of this study is to assess the impact of information on doctors' attitudes and perceptions toward generics. A cross-sectional survey based on a specially designed 21-item questionnaire was conducted. The survey involved doctors of different specialties working in a public hospital in Greece. The analysis includes descriptive and inferential statistics, reliability and validity tests, as well as structural equation modeling to evaluate the causal model. Statistical analysis was accomplished by using SPSS 20 and Amos 20. A total of 134 questionnaires out of 162 were received, providing a response rate of 82.71%. A number of significant associations were found between information and perceptions about generic medicines with demographic characteristics. It seems that the provision of quality information on generic drugs influences doctors' attitudes and prescription practices toward generic drugs. This is not a static process but a rather dynamic issue involving information provision policies for strengthening the proper doctors' attitudes toward generic drugs. © The Author(s) 2016.

  3. Impact of water boundary layer diffusion on the nitrification rate of submerged biofilter elements from a recirculating aquaculture system.

    PubMed

    Prehn, Jonas; Waul, Christopher K; Pedersen, Lars-Flemming; Arvin, Erik

    2012-07-01

    Total ammonia nitrogen (TAN) removal by microbial nitrification is an essential process in recirculating aquaculture systems (RAS). In order to protect the aquatic environment and fish health, it is important to be able to predict the nitrification rates in RAS's. The aim of this study was to determine the impact of hydraulic film diffusion on the nitrification rate in a submerged biofilter. Using an experimental batch reactor setup with recirculation, active nitrifying biofilter units from a RAS were exposed to a range of hydraulic flow velocities. Corresponding nitrification rates were measured following ammonium chloride, NH₄Cl, spikes and the impact of hydraulic film diffusion was quantified. The nitrification performance of the tested biofilter could be significantly increased by increasing the hydraulic flow velocity in the filter. Area based first order nitrification rate constants ranged from 0.065 m d⁻¹ to 0.192 m d⁻¹ for flow velocities between 2.5 m h⁻¹ and 40 m h⁻¹ (18 °C). This study documents that hydraulic film diffusion may have a significant impact on the nitrification rate in fixed film biofilters with geometry and hydraulic flows corresponding to our experimental RAS biofilters. The results may thus have practical implications in relation to the design, operational strategy of RAS biofilters and how to optimize TAN removal in fixed film biofilter systems. Copyright © 2012 Elsevier Ltd. All rights reserved.

  4. Self-diffusion of vibrational states: Impact on the heat transfer in hypersonic flows

    NASA Astrophysics Data System (ADS)

    Josyula, E.; Kustova, E. V.; Vedula, P.

    2014-12-01

    In the present paper, the influence of self-diffusion of vibrationally excited states on the fluid dynamics and surface heat transfer in an axisymmetric Mach 7.2 air flow past a sphere-cone is discussed. Two models for state-to-state transport properties are considered: a simplified model using the Eucken's relation for thermal conductivity and Fick's law for diffusion velocities with the constant Lewis number, and a rigorous kinetic theory based model for the calculation of state-specific thermal conductivity, diffusion and thermal diffusion coefficients. The simplified model is applied for the flowfield simulation to avoid high computational costs. For the application of the accurate kinetic theory approach, a post-processing procedure is used. Inclusion of self-diffusion results in an increase in the surface heat flux of up to 6.5% upstream of a shoulder region. Thermal conductivity is found to be the primary contributor to surface heat flux; the influence of mass and thermal diffusion is found to be negligible. Self-diffusion has a considerably greater influence in decreasing heat flux in the downstream regions far from stagnation point.

  5. Comparing impacts between formal and informal recreational trails.

    PubMed

    Pickering, Catherine Marina; Norman, Patrick

    2017-05-15

    Globally there are hundreds of thousands of kilometres of recreational trails traversing natural areas of high conservation value: but what are their impacts and do impacts differ among trails? We compared the effects of four common types of recreational trails [(1) narrow and (2) medium width informal bare earth trails and (3) gravel and (4) tarmac/concrete formal trails] on vegetation adjacent to trails in a high conservation value plant community that is popular for mountain biking and hiking in Australia. Plant species composition was recorded in quadrats along the edge of the four types of trails and in control sites away from trails. Vegetation cover, the cover of individual growth forms, and species richness along the edges of all four types of trails were similar to the controls, although the wider trails affected plant composition, with the tarmac and gravel trails favouring different species. With very few comparative studies, more research is required to allow managers and researchers to directly compare differences in the severity and types of impacts on vegetation among trails. In the meantime, limiting damage to vegetation on the edge of hardened trails during construction, use and maintenance is important, and hardening trails may not always be appropriate. Copyright © 2016. Published by Elsevier Ltd.

  6. Impact of delayed information in sub-second complex systems

    NASA Astrophysics Data System (ADS)

    Manrique, Pedro D.; Zheng, Minzhang; Johnson Restrepo, D. Dylan; Hui, Pak Ming; Johnson, Neil F.

    What happens when you slow down the delivery of information in large-scale complex systems that operate faster than the blink of an eye? This question just adopted immediate commercial, legal and political importance following U.S. regulators' decision to allow an intentional 350 microsecond delay to be added in the ultrafast network of financial exchanges. However there is still no scientific understanding available to policymakers of the potential system-wide impact of such delays. Here we take a first step in addressing this question using a minimal model of a population of competing, heterogeneous, adaptive agents which has previously been shown to produce similar statistical features to real markets. We find that while certain extreme system-level behaviors can be prevented by such delays, the duration of others is increased. This leads to a highly non-trivial relationship between delays and system-wide instabilities which warrants deeper empirical investigation. The generic nature of our model suggests there should be a fairly wide class of complex systems where such delay-driven extreme behaviors can arise, e.g. sub-second delays in brain function possibly impacting individuals' behavior, and sub-second delays in navigational systems potentially impacting the safety of driverless vehicles.

  7. Environmental impacts of modern agricultural technology diffusion in Bangladesh: an analysis of farmers' perceptions and their determinants.

    PubMed

    Rahman, Sanzidur

    2003-06-01

    Farmers' perception of the environmental impacts of modern agricultural technology diffusion and factors determining such awareness were examined using survey data from 21 villages in three agro-ecological regions of Bangladesh. Results reveal that farmers are well aware of the adverse environmental impacts of modern agricultural technology, although their awareness remains confined within visible impacts such as soil fertility, fish catches, and health effects. Their perception of intangible impacts such as, toxicity in water and soils is weak. Level and duration of modern agricultural technology adoption directly influence awareness of its adverse effects. Education and extension contacts also play an important role in raising awareness. Awareness is higher among farmers in developed regions, fertile locations and those with access to off-farm income sources. Promotion of education and strengthening extension services will boost farmers' environmental awareness. Infrastructure development and measures to replenish depleting soil fertility will also play a positive role in raising awareness.

  8. Rare events and their impact on velocity diffusion in a stochastic Fermi-Ulam model.

    PubMed

    Karlis, A K; Diakonos, F K; Constantoudis, V; Schmelcher, P

    2008-10-01

    A simplified version of the stochastic Fermi-Ulam model is investigated in order to elucidate the effect of a class of rare low-velocity events on the velocity diffusion process and consequently Fermi acceleration. The relative fraction of these events, for sufficiently large times, decreases monotonically with increasing variance of the magnitude of the particle velocity. However, a treatment of the diffusion problem which totally neglects these events, gives rise to a glaring inconsistency associated with the mean value of the magnitude of the velocity in the ensemble. We propose a general scheme for treating the diffusion process in velocity space, which succeeds in capturing the effect of the low-velocity events on the diffusion, providing a consistent description of the acceleration process. The present study exemplifies the influence of low-probability events on the transport properties of time-dependent billiards.

  9. Impact of Measurement System Characteristics on Advanced Sounder Information Content

    NASA Technical Reports Server (NTRS)

    Larar, Allen M.; Liu, Xu; Zhou, Daniel K.

    2011-01-01

    Advanced satellite sensors are tasked with improving global observations of the Earth's atmosphere, clouds, and surface to enable enhancements in weather prediction, climate monitoring capability, and environmental change detection. Achieving such an improvement in geophysical information inferred from these observations requires optimal usage of data from current systems as well as instrument system enhancements for future sensors. This presentation addresses results of tradeoff studies evaluating the impact of spectral resolution, spectral coverage, instrument noise, and a priori knowledge on remote sensing system information content, with a specific emphasis on thermodynamic state and trace species information obtainable from advanced atmospheric sounders. Particular attention will be devoted toward information achievable from the Atmospheric InfraRed Sounder (AIRS) on the NASA EOS Aqua satellite in orbit since 2002, the Infrared Atmospheric Sounding Interferometer (IASI) aboard MetOp-A since 2006, and the Cross-track Infrared Sounder (CrIS) instrument to fly aboard the NPP and JPSS series of satellites expected to begin in late 2011. While all of these systems cover nearly the same infrared spectral extent, they have very different number of channels, instrument line shapes, coverage continuity, and instrument noise. AIRS is a grating spectrometer having 2378 discrete spectral channels ranging from about 0.4 to 2.2/cm resolution; IASI is a Michelson interferometer with 8461 uniformly-spaced spectral channels of 0.5/cm (apodized) resolution; and CrIS is a Michelson interferometer having 1305 spectral channels of 0.625, 1.250, and 2.50/cm (unapodized) spectral resolution, respectively, over its three continuous but non-overlapping bands. Results of tradeoff studies showing information content sensitivity to assumed measurement system characteristics will be presented.

  10. Impact of Repeated Exposures on Information Spreading in Social Networks.

    PubMed

    Zhou, Cangqi; Zhao, Qianchuan; Lu, Wenbo

    2015-01-01

    Clustered structure of social networks provides the chances of repeated exposures to carriers with similar information. It is commonly believed that the impact of repeated exposures on the spreading of information is nontrivial. Does this effect increase the probability that an individual forwards a message in social networks? If so, to what extent does this effect influence people's decisions on whether or not to spread information? Based on a large-scale microblogging data set, which logs the message spreading processes and users' forwarding activities, we conduct a data-driven analysis to explore the answer to the above questions. The results show that an overwhelming majority of message samples are more probable to be forwarded under repeated exposures, compared to those under only a single exposure. For those message samples that cover various topics, we observe a relatively fixed, topic-independent multiplier of the willingness of spreading when repeated exposures occur, regardless of the differences in network structure. We believe that this finding reflects average people's intrinsic psychological gain under repeated stimuli. Hence, it makes sense that the gain is associated with personal response behavior, rather than network structure. Moreover, we find that the gain is robust against the change of message popularity. This finding supports that there exists a relatively fixed gain brought by repeated exposures. Based on the above findings, we propose a parsimonious model to predict the saturated numbers of forwarding activities of messages. Our work could contribute to better understandings of behavioral psychology and social media analytics.

  11. Impacts of Diffuse Radiation on Light Use Efficiency across Terrestrial Ecosystems Based on Eddy Covariance Observation in China

    PubMed Central

    Huang, Kun; Wang, Shaoqiang; Zhou, Lei; Wang, Huimin; Zhang, Junhui; Yan, Junhua; Zhao, Liang; Wang, Yanfen; Shi, Peili

    2014-01-01

    Ecosystem light use efficiency (LUE) is a key factor of production models for gross primary production (GPP) predictions. Previous studies revealed that ecosystem LUE could be significantly enhanced by an increase on diffuse radiation. Under large spatial heterogeneity and increasing annual diffuse radiation in China, eddy covariance flux data at 6 sites across different ecosystems from 2003 to 2007 were used to investigate the impacts of diffuse radiation indicated by the cloudiness index (CI) on ecosystem LUE in grassland and forest ecosystems. Our results showed that the ecosystem LUE at the six sites was significantly correlated with the cloudiness variation (0.24≤R2≤0.85), especially at the Changbaishan temperate forest ecosystem (R2 = 0.85). Meanwhile, the CI values appeared more frequently between 0.8 and 1.0 in two subtropical forest ecosystems (Qianyanzhou and Dinghushan) and were much larger than those in temperate ecosystems. Besides, cloudiness thresholds which were favorable for enhancing ecosystem carbon sequestration existed at the three forest sites, respectively. Our research confirmed that the ecosystem LUE at the six sites in China was positively responsive to the diffuse radiation, and the cloudiness index could be used as an environmental regulator for LUE modeling in regional GPP prediction. PMID:25393629

  12. Impacts of diffuse radiation on light use efficiency across terrestrial ecosystems based on Eddy covariance observation in China.

    PubMed

    Huang, Kun; Wang, Shaoqiang; Zhou, Lei; Wang, Huimin; Zhang, Junhui; Yan, Junhua; Zhao, Liang; Wang, Yanfen; Shi, Peili

    2014-01-01

    Ecosystem light use efficiency (LUE) is a key factor of production models for gross primary production (GPP) predictions. Previous studies revealed that ecosystem LUE could be significantly enhanced by an increase on diffuse radiation. Under large spatial heterogeneity and increasing annual diffuse radiation in China, eddy covariance flux data at 6 sites across different ecosystems from 2003 to 2007 were used to investigate the impacts of diffuse radiation indicated by the cloudiness index (CI) on ecosystem LUE in grassland and forest ecosystems. Our results showed that the ecosystem LUE at the six sites was significantly correlated with the cloudiness variation (0.24 ≤ R(2) ≤ 0.85), especially at the Changbaishan temperate forest ecosystem (R(2) = 0.85). Meanwhile, the CI values appeared more frequently between 0.8 and 1.0 in two subtropical forest ecosystems (Qianyanzhou and Dinghushan) and were much larger than those in temperate ecosystems. Besides, cloudiness thresholds which were favorable for enhancing ecosystem carbon sequestration existed at the three forest sites, respectively. Our research confirmed that the ecosystem LUE at the six sites in China was positively responsive to the diffuse radiation, and the cloudiness index could be used as an environmental regulator for LUE modeling in regional GPP prediction.

  13. NASA/DOD Aerospace Knowledge Diffusion Research Project. Paper 12: The diffusion of federally funded aerospace research and development (R/D) and the information seeking behavior of US aerospace engineers and scientists

    NASA Technical Reports Server (NTRS)

    Pinelli, Thomas E.; Kennedy, John M.; Barclay, Rebecca O.

    1991-01-01

    In this paper, the diffusion of federally funded aerospace R&D is explored from the perspective of the information-seeking behavior of U.S. aerospace engineers and scientists. The following three assumptions frame this exploration: (1) knowledge production, transfer, and utilization are equally important components of the aerospace R&D process; (2) the diffusion of knowledge resulting from federally funded aerospace R&D is indispensable for the U.S. to remain a world leader in aerospace; and (3) U.S. government technical reports, produced by NASA and DOD, play an important, but as yet undefined, role in the diffusion of federally funded aerospace R&D. A conceptual model for federally funded aerospace knowledge diffusion, one that emphasizes U.S. goverment technical reports, is presented. Data regarding three research questions concerning the information-seeking behavior of U.S. aerospace engineers and scientists are also presented.

  14. The impact of IAIMS on the work of information experts. Integrated Advanced Information Management Systems.

    PubMed Central

    Ash, J

    1995-01-01

    Integrated Advanced Information Management Systems (IAIMS) programs differ but have certain characteristics in common. Technological and organizational integration are universal goals. As integration takes place, what happens to those implementing the vision? A survey of 125 staff members, or information experts, involved in information or informatics at an IAIMS-funded institution was conducted during the last year of the implementation phase. The purpose was to measure the impact of IAIMS on the jobs of those in the library and related service units, and the computing, telecommunications, and health informatics divisions. The researchers used newly developed scales measuring levels of integration (knowledge of and involvement with other departments), customer orientation (focus on the user), and informatedness (changes in the nature of work beyond automation of former routines). Ninety-four percent of respondents indicated that their jobs had changed a great deal; the changes were similar regardless of division. To further investigate the impact of IAIMS on librarians in particular, a separate skills survey was conducted. The IAIMS librarians indicated that technology and training skills are especially needed in the new, integrated environment. PMID:8547905

  15. The impact of IAIMS on the work of information experts. Integrated Advanced Information Management Systems.

    PubMed

    Ash, J

    1995-10-01

    Integrated Advanced Information Management Systems (IAIMS) programs differ but have certain characteristics in common. Technological and organizational integration are universal goals. As integration takes place, what happens to those implementing the vision? A survey of 125 staff members, or information experts, involved in information or informatics at an IAIMS-funded institution was conducted during the last year of the implementation phase. The purpose was to measure the impact of IAIMS on the jobs of those in the library and related service units, and the computing, telecommunications, and health informatics divisions. The researchers used newly developed scales measuring levels of integration (knowledge of and involvement with other departments), customer orientation (focus on the user), and informatedness (changes in the nature of work beyond automation of former routines). Ninety-four percent of respondents indicated that their jobs had changed a great deal; the changes were similar regardless of division. To further investigate the impact of IAIMS on librarians in particular, a separate skills survey was conducted. The IAIMS librarians indicated that technology and training skills are especially needed in the new, integrated environment.

  16. Impact of information and communication technology on child health.

    PubMed

    Woo, Eugenia Hc; White, Peter; Lai, Christopher Wk

    2016-06-01

    This article provides a general framework for understanding the use of information and communication technology in education and discusses the impact of computer usage on students' health and development. Potential beneficial and harmful effects of computer use by children are discussed. Early epidemiological and laboratory studies have indicated that children are at least of similar risk of developing musculoskeletal and vision problems as adults, and musculoskeletal and visual health problems developed in childhood are likely to persist into adulthood. This article, therefore, aims to provide a reflection on the deficits of existing policy and recommendations for child-specific guidelines in computer use. © 2016 Paediatrics and Child Health Division (The Royal Australasian College of Physicians).

  17. Impact of diffusion on transverse dispersion in two-dimensional ordered and random porous media

    NASA Astrophysics Data System (ADS)

    Hlushkou, Dzmitry; Piatrusha, Stanislau; Tallarek, Ulrich

    2017-06-01

    Solute dispersion in fluid flow results from the interaction between advection and diffusion. The relative contributions of these two mechanisms to mass transport are characterized by the reduced velocity ν , also referred to as the Péclet number. In the absence of diffusion (i.e., when the solute diffusion coefficient Dm=0 and ν →∞ ), divergence-free laminar flow of an incompressible fluid results in a zero-transverse dispersion coefficient (DT=0 ) , both in ordered and random two-dimensional porous media. We demonstrate by numerical simulations that a more realistic realization of the condition ν →∞ using Dm≠0 and letting the fluid flow velocity approach infinity leads to completely different results for ordered and random two-dimensional porous media. With increasing reduced velocity, DT approaches an asymptotic value in ordered two-dimensional porous media but grows linearly in disordered (random) structures depending on the geometrical disorder of a structure: a higher degree of heterogeneity results in a stronger growth of DT with ν . The obtained results reveal that disorder in the geometrical structure of a two-dimensional porous medium leads to a growth of DT with ν even in a uniform pore-scale advection field; however, lateral diffusion is a prerequisite for this growth. By contrast, in ordered two-dimensional porous media the presence of lateral diffusion leads to a plateau for the transverse dispersion coefficient with increasing ν .

  18. Geographical information system methodology and instruction impact on water managers

    NASA Astrophysics Data System (ADS)

    McCowan, Ladonna Cecile

    Scope and method of study. Solutions addressing the dilemma of nonpoint source [NPS] pollution are dependent on education, assessment, and best management practices [BMP]. Educational programs must provide and simplify complex relationships between NPS and water quality. This study evaluates the impact of a geographical information system [GIS] methodology and its instruction to water managers by assessing changes in their attitude, perceived knowledge, and planned management practices. Findings and conclusion. Water managers knowledge and behavior were not found significantly different between the GIS and without-GIS courses. There was a significant difference between the courses for attitude. However, the significance was in favor of the without-GIS workshop. The pre- then post-survey was inadequate to establish reliable baseline data for the water managers. Over estimation to pre-survey questions generated inaccuracies in the post-survey data. The result of the course presentation had an impact on the water managers perceived knowledge, attitude and planned behavior toward water quality. GIS methodology has potential for enhances educational material for water managers.

  19. Nanotechnology knowledge diffusion: measuring the impact of the research networking and a strategy for improvement

    NASA Astrophysics Data System (ADS)

    Liu, Xuan; Jiang, Shan; Chen, Hsinchun; Larson, Catherine A.; Roco, Mihail C.

    2014-09-01

    Given the global increase in public funding for nanotechnology research and development, it is even more important to support projects with promising return on investment. A main return is the benefit to other researchers and to the entire field through knowledge diffusion, invention, and innovation. The social network of researchers is one of the channels through which this happens. This study considers the scientific publication network in the field of nanotechnology, and evaluates how knowledge diffusion through coauthorship and citations is affected in large institutions by the location and connectivity of individual researchers in the network. The relative position and connectivity of a researcher is measured by various social network metrics, including degree centrality, Bonacich Power centrality, structural holes, and betweenness centrality. Leveraging the Cox regression model, we analyzed the temporal relationships between knowledge diffusion and social network measures of researchers in five leading universities in the United States using papers published from 2000 to 2010. The results showed that the most significant effects on knowledge diffusion in the field of nanotechnology were from the structural holes of the network and the degree centrality of individual researchers. The data suggest that a researcher has potential to perform better in knowledge creation and diffusion on boundary-spanning positions between different communities and when he or she has a high level of connectivity in the knowledge network. These observations may lead to improved strategies in planning, conducting, and evaluating multidisciplinary nanotechnology research. The paper also identifies the researchers who made most significant contributions to nanotechnology knowledge diffusion in the networks of five leading U.S. universities.

  20. Information geometric analysis of phase transitions in complex patterns: the case of the Gray-Scott reaction-diffusion model

    NASA Astrophysics Data System (ADS)

    Har-Shemesh, Omri; Quax, Rick; Hoekstra, Alfons G.; Sloot, Peter M. A.

    2016-04-01

    The Fisher-Rao metric from information geometry is related to phase transition phenomena in classical statistical mechanics. Several studies propose to extend the use of information geometry to study more general phase transitions in complex systems. However, it is unclear whether the Fisher-Rao metric does indeed detect these more general transitions, especially in the absence of a statistical model. In this paper we study the transitions between patterns in the Gray-Scott reaction-diffusion model using Fisher information. We describe the system by a probability density function that represents the size distribution of blobs in the patterns and compute its Fisher information with respect to changing the two rate parameters of the underlying model. We estimate the distribution non-parametrically so that we do not assume any statistical model. The resulting Fisher map can be interpreted as a phase-map of the different patterns. Lines with high Fisher information can be considered as boundaries between regions of parameter space where patterns with similar characteristics appear. These lines of high Fisher information can be interpreted as phase transitions between complex patterns.

  1. Modeling the impacts of solar radiation partitioning into direct and diffuse fractions for the global water cycle

    NASA Astrophysics Data System (ADS)

    Oliveira, Paulo J. C.; Davin, Edouard L.; Seneviratne, Sonia I.

    2010-05-01

    Incident solar radiation at the Earth's surface affects plant photosynthesis and evapotranspiration, and consequently the global water budget. Observations from 1960-1990's across the Northern Hemisphere suggest that increased aerosol loadings from industrialization led not only to a decline in the intensity of solar radiation at the surface (global dimming), but also to a higher fraction of scattered light, which enhanced plant photosynthesis and the land carbon sink, with probable concurrent impacts on the water cycle. Thus, we used the NCAR Community Land Model (version 3.5) to perform global offline simulations and study the effects of the imposition of changes to radiation partitioning in diffuse and direct fractions on trends in evapotranspiration and runoff. We find that most modeled land surface variables respond to an increased-diffuse simulation where the relative fraction of radiation is changed globally at a high rate of increased diffuse as reported by some observation stations. Increased-diffuse partitioning causes a rise in total ET in all regions, an effect of opposite sign but smaller absolute value than that resulting from global dimming. Evapotranspiration rises by over 0.5 watt/m2 per decade in the tropics, due to increased shaded leaf stomatal conductance, with an opposite effect noted elsewhere due to lower ground evaporation. In the eastern U.S.A. and the Amazon basin, decadal trend anomalies in evapotranspiration for increased-diffuse radiation change reach 25-30% the absolute magnitude of those caused by dimming. Reductions to river runoff are modest nearly everywhere outside the Amazon. Understanding the mechanisms behind the interactions between solar radiation and the various land-surface components will help the development of climate models, improving predictions, in particular regarding changes in terrestrial hydrologic resources.

  2. Diffusion in liquid metal systems. [information on electrical resistivity and thermal conductivity

    NASA Technical Reports Server (NTRS)

    Ukanwa, A. O.

    1975-01-01

    Physical properties of twenty liquid metals are reported; some of the data on such liquid metal properties as density, electrical resistivity, thermal conductivity, and heat capacity are summarized in graphical form. Data on laboratory handling and safety procedure are summarized for each metal; heat-transfer-correlations for liquid metals under various conditions of laminar and turbulent flow are included. Where sufficient data were available, temperature equations of properties were obtained by the method of least-squares fit. All values of properties given are valid in the given liquid phase ranges only. Additional tabular data on some 40 metals are reported in the appendix. Included is a brief description of experiments that were performed to investigate diffusion in liquid indium-gallium systems.

  3. Characterizing Brain Structures and Remodeling after TBI Based on Information Content, Diffusion Entropy

    PubMed Central

    Fozouni, Niloufar; Chopp, Michael; Nejad-Davarani, Siamak P.; Zhang, Zheng Gang; Lehman, Norman L.; Gu, Steven; Ueno, Yuji; Lu, Mei; Ding, Guangliang; Li, Lian; Hu, Jiani; Bagher-Ebadian, Hassan; Hearshen, David; Jiang, Quan

    2013-01-01

    Background To overcome the limitations of conventional diffusion tensor magnetic resonance imaging resulting from the assumption of a Gaussian diffusion model for characterizing voxels containing multiple axonal orientations, Shannon's entropy was employed to evaluate white matter structure in human brain and in brain remodeling after traumatic brain injury (TBI) in a rat. Methods Thirteen healthy subjects were investigated using a Q-ball based DTI data sampling scheme. FA and entropy values were measured in white matter bundles, white matter fiber crossing areas, different gray matter (GM) regions and cerebrospinal fluid (CSF). Axonal densities' from the same regions of interest (ROIs) were evaluated in Bielschowsky and Luxol fast blue stained autopsy (n = 30) brain sections by light microscopy. As a case demonstration, a Wistar rat subjected to TBI and treated with bone marrow stromal cells (MSC) 1 week after TBI was employed to illustrate the superior ability of entropy over FA in detecting reorganized crossing axonal bundles as confirmed by histological analysis with Bielschowsky and Luxol fast blue staining. Results Unlike FA, entropy was less affected by axonal orientation and more affected by axonal density. A significant agreement (r = 0.91) was detected between entropy values from in vivo human brain and histologically measured axonal density from post mortum from the same brain structures. The MSC treated TBI rat demonstrated that the entropy approach is superior to FA in detecting axonal remodeling after injury. Compared with FA, entropy detected new axonal remodeling regions with crossing axons, confirmed with immunohistological staining. Conclusions Entropy measurement is more effective in distinguishing axonal remodeling after injury, when compared with FA. Entropy is also more sensitive to axonal density than axonal orientation, and thus may provide a more accurate reflection of axonal changes that occur in neurological injury and disease

  4. Characterizing brain structures and remodeling after TBI based on information content, diffusion entropy.

    PubMed

    Fozouni, Niloufar; Chopp, Michael; Nejad-Davarani, Siamak P; Zhang, Zheng Gang; Lehman, Norman L; Gu, Steven; Ueno, Yuji; Lu, Mei; Ding, Guangliang; Li, Lian; Hu, Jiani; Bagher-Ebadian, Hassan; Hearshen, David; Jiang, Quan

    2013-01-01

    To overcome the limitations of conventional diffusion tensor magnetic resonance imaging resulting from the assumption of a Gaussian diffusion model for characterizing voxels containing multiple axonal orientations, Shannon's entropy was employed to evaluate white matter structure in human brain and in brain remodeling after traumatic brain injury (TBI) in a rat. Thirteen healthy subjects were investigated using a Q-ball based DTI data sampling scheme. FA and entropy values were measured in white matter bundles, white matter fiber crossing areas, different gray matter (GM) regions and cerebrospinal fluid (CSF). Axonal densities' from the same regions of interest (ROIs) were evaluated in Bielschowsky and Luxol fast blue stained autopsy (n = 30) brain sections by light microscopy. As a case demonstration, a Wistar rat subjected to TBI and treated with bone marrow stromal cells (MSC) 1 week after TBI was employed to illustrate the superior ability of entropy over FA in detecting reorganized crossing axonal bundles as confirmed by histological analysis with Bielschowsky and Luxol fast blue staining. Unlike FA, entropy was less affected by axonal orientation and more affected by axonal density. A significant agreement (r = 0.91) was detected between entropy values from in vivo human brain and histologically measured axonal density from post mortum from the same brain structures. The MSC treated TBI rat demonstrated that the entropy approach is superior to FA in detecting axonal remodeling after injury. Compared with FA, entropy detected new axonal remodeling regions with crossing axons, confirmed with immunohistological staining. Entropy measurement is more effective in distinguishing axonal remodeling after injury, when compared with FA. Entropy is also more sensitive to axonal density than axonal orientation, and thus may provide a more accurate reflection of axonal changes that occur in neurological injury and disease.

  5. Impact of Repeated Exposures on Information Spreading in Social Networks

    PubMed Central

    Zhou, Cangqi; Zhao, Qianchuan; Lu, Wenbo

    2015-01-01

    Clustered structure of social networks provides the chances of repeated exposures to carriers with similar information. It is commonly believed that the impact of repeated exposures on the spreading of information is nontrivial. Does this effect increase the probability that an individual forwards a message in social networks? If so, to what extent does this effect influence people’s decisions on whether or not to spread information? Based on a large-scale microblogging data set, which logs the message spreading processes and users’ forwarding activities, we conduct a data-driven analysis to explore the answer to the above questions. The results show that an overwhelming majority of message samples are more probable to be forwarded under repeated exposures, compared to those under only a single exposure. For those message samples that cover various topics, we observe a relatively fixed, topic-independent multiplier of the willingness of spreading when repeated exposures occur, regardless of the differences in network structure. We believe that this finding reflects average people’s intrinsic psychological gain under repeated stimuli. Hence, it makes sense that the gain is associated with personal response behavior, rather than network structure. Moreover, we find that the gain is robust against the change of message popularity. This finding supports that there exists a relatively fixed gain brought by repeated exposures. Based on the above findings, we propose a parsimonious model to predict the saturated numbers of forwarding activities of messages. Our work could contribute to better understandings of behavioral psychology and social media analytics. PMID:26465749

  6. Diffusion in Colocation Contact Networks: The Impact of Nodal Spatiotemporal Dynamics

    PubMed Central

    Thomas, Bryce; Jurdak, Raja; Zhao, Kun; Atkinson, Ian

    2016-01-01

    Temporal contact networks are studied to understand dynamic spreading phenomena such as communicable diseases or information dissemination. To establish how spatiotemporal dynamics of nodes impact spreading potential in colocation contact networks, we propose “inducement-shuffling” null models which break one or more correlations between times, locations and nodes. By reconfiguring the time and/or location of each node’s presence in the network, these models induce alternative sets of colocation events giving rise to contact networks with varying spreading potential. This enables second-order causal reasoning about how correlations in nodes’ spatiotemporal preferences not only lead to a given contact network but ultimately influence the network’s spreading potential. We find the correlation between nodes and times to be the greatest impediment to spreading, while the correlation between times and locations slightly catalyzes spreading. Under each of the presented null models we measure both the number of contacts and infection prevalence as a function of time, with the surprising finding that the two have no direct causality. PMID:27501240

  7. Runaway Electron Preionized Diffuse Discharge and Its Impact on Plane Anode

    NASA Astrophysics Data System (ADS)

    Tarasenko, Victor; Erofeev, Michael; Ripenko, Vasilii; Shulepov, Mikhail; Baksht, Evgenii; National Research Tomsk Polytechnic University Collaboration; Institute of High Current Electronics Collaboration

    2016-09-01

    The spatial structure of a runaway electrons preionized diffuse discharge (REP DD) in nonuniform electric field and the influence of its plasma on the surface of a plane anode have been studied. In our experiments, we used a NPG-18/3500N high-voltage generator. The incident voltage had negative polarity, amplitude of 20 kV, and FWHM of 6 ns; the discharge current was up to 200 A. The discharge plasma was formed in nitrogen by applying high voltage pulses to the interelectrode gap which was varied between 2 and 9 mm. Under such conditions, the specific input power reached up to 10 MW/cm3. It is established that diffuse channel is the initial stage of the discharge radiation; then anode spot, channel with high glow intensity based on the anode spot and spark channel are consecutively formed. Spark formation finished within 10-15 ns after the onset of the discharge. Microstructure of spark and diffuse channels with anode spot autograph have been detected. The traces of such discharge represents itself an aggregation of up to 100 microcraters with dimeters of 5-100 micrometers. It was also shown that diffuse discharge does not leave erosive action on an anode surface or on its carbon cover. This work was supported by the Russian Science Foundation under the Grant Number 14-29-00052.

  8. Spatial Resolution, Grayscale, and Error Diffusion Trade-offs: Impact on Display System Design

    NASA Technical Reports Server (NTRS)

    Gille, Jennifer L. (Principal Investigator)

    1996-01-01

    We examine technology trade-offs related to grayscale resolution, spatial resolution, and error diffusion for tessellated display systems. We present new empirical results from our psychophysical study of these trade-offs and compare them to the predictions of a model of human vision.

  9. Impact of density information on Rayleigh surface wave inversion results

    NASA Astrophysics Data System (ADS)

    Ivanov, Julian; Tsoflias, Georgios; Miller, Richard D.; Peterie, Shelby; Morton, Sarah; Xia, Jianghai

    2016-12-01

    We assessed the impact of density on the estimation of inverted shear-wave velocity (Vs) using the multi-channel analysis of surface waves (MASW) method. We considered the forward modeling theory, evaluated model sensitivity, and tested the effect of density information on the inversion of seismic data acquired in the Arctic. Theoretical review, numerical modeling and inversion of modeled and real data indicated that the density ratios between layers, not the actual density values, impact the determination of surface-wave phase velocities. Application on real data compared surface-wave inversion results using: a) constant density, the most common approach in practice, b) indirect density estimates derived from refraction compressional-wave velocity observations, and c) from direct density measurements in a borehole. The use of indirect density estimates reduced the final shear-wave velocity (Vs) results typically by 6-7% and the use of densities from a borehole reduced the final Vs estimates by 10-11% compared to those from assumed constant density. In addition to the improved absolute Vs accuracy, the resulting overall Vs changes were unevenly distributed laterally when viewed on a 2-D section leading to an overall Vs model structure that was more representative of the subsurface environment. It was observed that the use of constant density instead of increasing density with depth not only can lead to Vs overestimation but it can also create inaccurate model structures, such as a low-velocity layer. Thus, optimal Vs estimations can be best achieved using field estimates of subsurface density ratios.

  10. European information on climate change impacts, vulnerability and adaptation

    NASA Astrophysics Data System (ADS)

    Jol, A.; Isoard, S.

    2010-09-01

    development in 2010 and is likely to manage the system after 2011. The European Commission in its Communication in 2009 on disaster risk prevention also calls for improving and better sharing of data on disasters, disaster risk mapping and disaster risk management, in the context of the EU civil protection mechanism. Such information might also be linked to the planned EU Clearinghouse on climate change adaptation. The activities of EEA on climate change impacts, vulnerability and adaptation (including disaster risk reduction) include indicators of the impacts of climate change; a regularly updated overview of national assessments and adaptation plans on the EEA web site and specific focused reports, e.g. on adaptation to the challenges of changing water resources in the Alps (2009) and on analysis of past trends in natural disasters (due in 2010) and regular expert meetings and workshops with EEA member countries. The ECAC presentation will include the latest developments in the EU Clearinghouse on adaptation and progress in relevant EEA activities.

  11. Diffusion-weighted magnetic resonance imaging of the musculoskeletal system: an emerging technology with potential to impact clinical decision making.

    PubMed

    Beattie, Paul F

    2011-11-01

    Diffusion-weighted imaging (DWI) is an application of magnetic resonance imaging that allows the measurement of water movement within and between tissues. Originally developed as a way of detecting early signs of stroke or brain disease, DWI is now being used to study physiologic events within the musculoskeletal system. The accurate measurement of water diffusion can provide important information regarding tissue responses associated with trauma and disease, as well as offer insight toward the mechanism by which physical therapy interventions affect tissues. The purpose of this paper is to discuss the rationale for DWI and its potential clinical and research applications for patients with musculoskeletal disorders. Specific examples of the use of DWI for patients with painful spinal disorders are used as illustrations.

  12. NASA/DOD Aerospace Knowledge Diffusion Research Project. Paper 12: The diffusion of federally funded aerospace Research and Development (R&D) and the information seeking behavior of US aerospace engineers and scientists

    NASA Technical Reports Server (NTRS)

    Pinelli, Thomas E.; Kennedy, John M.; Barclay, Rebecca O.

    1991-01-01

    The present exploration of the diffusion of federally-funded R&D via the information-seeking behavior of scientists and engineers proceeds under three assumptions: (1) that knowledge transfer and utilization is as important as knowledge production; (2) that the diffusion of knowledge obtained through federally-funded R&D is necessary for the maintenance of U.S. preeminence in the aerospace field; and (3) that federally-funded NASA and DoD technical reports play an important, albeit as-yet undefined, role in aerospace R&D diffusion. A conceptual model is presented for the process of knowledge diffusion that stresses the role of U.S. government-funded technical reports.

  13. Social relevance: toward understanding the impact of the individual in an information cascade

    NASA Astrophysics Data System (ADS)

    Hall, Robert T.; White, Joshua S.; Fields, Jeremy

    2016-05-01

    Information Cascades (IC) through a social network occur due to the decision of users to disseminate content. We define this decision process as User Diffusion (UD). IC models typically describe an information cascade by treating a user as a node within a social graph, where a node's reception of an idea is represented by some activation state. The probability of activation then becomes a function of a node's connectedness to other activated nodes as well as, potentially, the history of activation attempts. We enrich this Coarse-Grained User Diffusion (CGUD) model by applying actor type logics to the nodes of the graph. The resulting Fine-Grained User Diffusion (FGUD) model utilizes prior research in actor typing to generate a predictive model regarding the future influence a user will have on an Information Cascade. Furthermore, we introduce a measure of Information Resonance that is used to aid in predictions regarding user behavior.

  14. Impact of the atomic layer deposition precursors diffusion on solid-state carbon nanotube based supercapacitors performances.

    PubMed

    Fiorentino, Giuseppe; Vollebregt, Sten; Tichelaar, F D; Ishihara, Ryoichi; Sarro, Pasqualina M

    2015-02-13

    A study on the impact of atomic layer deposition (ALD) precursors diffusion on the performance of solid-state miniaturized nanostructure capacitor array is presented. Three-dimensional nanostructured capacitor array based on double conformal coating of multiwalled carbon nanotubes (MWCNTs) bundles is realized using ALD to deposit Al2O3 as dielectric layer and TiN as high aspect-ratio conformal counter-electrode on 2 μm long MWCNT bundles. The devices have a small footprint (from 100 μm(2) to 2500 μm(2)) and are realized using an IC wafer-scale manufacturing process with high reproducibility (≤0.3E-12F deviation). To evaluate the enhancement of the electrode surface, the measured capacitance values are compared to a lumped circuital model. The observed discrepancies are explained with a partial coating of the CNT, that determine a limited use of the available electrode surface area. To analyze the CNT coating effectiveness, the ALD precursors diffusions inside the CNT bundle is studied using a Knudsen diffusion mechanism.

  15. Impact of mesophyll diffusion on estimated global land CO2 fertilization.

    PubMed

    Sun, Ying; Gu, Lianhong; Dickinson, Robert E; Norby, Richard J; Pallardy, Stephen G; Hoffman, Forrest M

    2014-11-04

    In C3 plants, CO2 concentrations drop considerably along mesophyll diffusion pathways from substomatal cavities to chloroplasts where CO2 assimilation occurs. Global carbon cycle models have not explicitly represented this internal drawdown and therefore overestimate CO2 available for carboxylation and underestimate photosynthetic responsiveness to atmospheric CO2. An explicit consideration of mesophyll diffusion increases the modeled cumulative CO2 fertilization effect (CFE) for global gross primary production (GPP) from 915 to 1,057 PgC for the period of 1901-2010. This increase represents a 16% correction, which is large enough to explain the persistent overestimation of growth rates of historical atmospheric CO2 by Earth system models. Without this correction, the CFE for global GPP is underestimated by 0.05 PgC/y/ppm. This finding implies that the contemporary terrestrial biosphere is more CO2 limited than previously thought.

  16. Impact of Mesophyll Diffusion on Estimated Global Land CO2 Fertilization

    NASA Astrophysics Data System (ADS)

    Sun, Y.; Gu, L.; Dickinson, R. E.

    2014-12-01

    In C3 plants, CO2 concentrations drop considerably along mesophyll diffusion pathways from substomatal cavities to chloroplasts where CO2 assimilation occurs. Global carbon cycle models have not explicitly represented this internal drawdown and so overestimate CO2 available for carboxylation and underestimate photosynthetic responsiveness to atmospheric CO2. An explicit consideration of mesophyll diffusion increases the modeled cumulative CO2 fertilization effect (CFE) for global gross primary production (GPP) from 915 PgC to 1057 PgC for the period of 1901 to 2010. This increase represents a 16% correction large enough to explain the persistent overestimation of growth rates of historical atmospheric CO2 by Earth System Models. Without this correction, the CFE for global GPP is underestimated by 0.05 PgC yr-1ppm-1. This finding implies that the contemporary terrestrial biosphere is more CO2-limited than previously thought.

  17. Impact of mesophyll diffusion on estimated global land CO2 fertilization

    PubMed Central

    Sun, Ying; Gu, Lianhong; Dickinson, Robert E.; Norby, Richard J.; Pallardy, Stephen G.; Hoffman, Forrest M.

    2014-01-01

    In C3 plants, CO2 concentrations drop considerably along mesophyll diffusion pathways from substomatal cavities to chloroplasts where CO2 assimilation occurs. Global carbon cycle models have not explicitly represented this internal drawdown and therefore overestimate CO2 available for carboxylation and underestimate photosynthetic responsiveness to atmospheric CO2. An explicit consideration of mesophyll diffusion increases the modeled cumulative CO2 fertilization effect (CFE) for global gross primary production (GPP) from 915 to 1,057 PgC for the period of 1901–2010. This increase represents a 16% correction, which is large enough to explain the persistent overestimation of growth rates of historical atmospheric CO2 by Earth system models. Without this correction, the CFE for global GPP is underestimated by 0.05 PgC/y/ppm. This finding implies that the contemporary terrestrial biosphere is more CO2 limited than previously thought. PMID:25313079

  18. Impact of mesophyll diffusion on estimated global land CO2 fertilization

    DOE PAGES

    Sun, Ying; Gu, Lianhong; Dickinson, Robert E.; ...

    2014-10-13

    In C3 plants, CO2 concentrations drop considerably along mesophyll diffusion pathways from substomatal cavities to chloroplasts where CO2 assimilation occurs. Global carbon cycle models have not explicitly represented this internal drawdown and so overestimate CO2 available for carboxylation and underestimate photosynthetic responsiveness to atmospheric CO2. An explicit consideration of mesophyll diffusion increases the modeled cumulative CO2 fertilization effect (CFE) for global gross primary production (GPP) from 915 PgC to 1057 PgC for the period of 1901 to 2010. This increase represents a 16% correction, large enough to explain the persistent overestimation of growth rates of historical atmospheric CO2 by Earthmore » System Models. Without this correction, the CFE for global GPP is underestimated by 0.05 PgC yr-1ppm-1. This finding implies that the contemporary terrestrial biosphere is more CO2-limited than previously thought.« less

  19. Atomic diffusion on vicinal surfaces: step roughening impact on step permeability

    NASA Astrophysics Data System (ADS)

    Ranguelov, B.; Michailov, M.

    2014-12-01

    The problem of mass transport in material science for systems with reduced dimensionality holds special academic and technological attention since the fine diffusion control of adatoms could initiate exotic nanoscale patterning at epitaxial interfaces. The present study brings out important details of the atomic diffusion mechanisms on vicinal surfaces, accounting for the subtle competition between an external field imposed on the migrating adatoms and the roughening of the steps bordering the atomic terraces. The computational model reveals a temperature gap for breakdown of step permeability in the vicinity of the step roughening transition and sheds light on recently observed experimental results for atomic step dynamics on Si surfaces. The present study also demonstrates the extended capability of atomistic models in computer simulations to unravel simultaneous effects, to distinguish between them, and finally to assess their specific contribution to experimentally observed complex physical phenomena.

  20. NASA/DOD Aerospace Knowledge Diffusion Research Project. Paper 5: Aerospace librarians and technical information specialists as information intermediaries: A report of phase 2 activities of the NASA/DOD Aerospace Knowledge Diffusion Research Project

    NASA Technical Reports Server (NTRS)

    Pinelli, Thomas E.; Kennedy, John M.

    1990-01-01

    The flow of U.S. government-funded and foreign scientific and technical information (STI) through libraries and related facilities to users in government and industry is examined, summarizing preliminary results of Phase 2 of the NASA/DOD Aerospace Knowledge Diffusion Research Project (NAKDRP). The design and objectives of NAKDRP are reviewed; the NAKDRP model of STI transfer among producers, STI intermediaries, surrogates (technical report repositories or clearinghouses), and users is explained and illustrated with diagrams; and particular attention is given to the organization and operation of aerospace libraries. In a survey of North American libraries it was found that 25-30 percent of libraries regularly receive technical reports from ESA and the UK; the corresponding figures for Germany and for France, Sweden, and Japan are 18 and 5 percent, respectively. Also included is a series of bar graphs showing the librarians' assessments of the quality and use of NASA Technical Reports.

  1. NASA/DOD Aerospace Knowledge Diffusion Research Project. Paper 5: Aerospace librarians and technical information specialists as information intermediaries: A report of phase 2 activities of the NASA/DOD Aerospace Knowledge Diffusion Research Project

    NASA Technical Reports Server (NTRS)

    Pinelli, Thomas E.; Kennedy, John M.

    1990-01-01

    The flow of U.S. government-funded and foreign scientific and technical information (STI) through libraries and related facilities to users in government and industry is examined, summarizing preliminary results of Phase 2 of the NASA/DOD Aerospace Knowledge Diffusion Research Project (NAKDRP). The design and objectives of NAKDRP are reviewed; the NAKDRP model of STI transfer among producers, STI intermediaries, surrogates (technical report repositories or clearinghouses), and users is explained and illustrated with diagrams; and particular attention is given to the organization and operation of aerospace libraries. In a survey of North American libraries it was found that 25-30 percent of libraries regularly receive technical reports from ESA and the UK; the corresponding figures for Germany and for France, Sweden, and Japan are 18 and 5 percent, respectively. Also included is a series of bar graphs showing the librarians' assessments of the quality and use of NASA Technical Reports.

  2. Impact of homogeneous strain on uranium vacancy diffusion in uranium dioxide

    DOE PAGES

    Goyal, Anuj; Phillpot, Simon R.; Subramanian, Gopinath; ...

    2015-03-03

    We present a detailed mechanism of, and the effect of homogeneous strains on, the migration of uranium vacancies in UO2. Vacancy migration pathways and barriers are identified using density functional theory and the effect of uniform strain fields are accounted for using the dipole tensor approach. We report complex migration pathways and noncubic symmetry associated with the uranium vacancy in UO2 and show that these complexities need to be carefully accounted for to predict the correct diffusion behavior of uranium vacancies. We show that under homogeneous strain fields, only the dipole tensor of the saddle with respect to the minimummore » is required to correctly predict the change in the energy barrier between the strained and the unstrained case. Diffusivities are computed using kinetic Monte Carlo simulations for both neutral and fully charged state of uranium single and divacancies. We calculate the effect of strain on migration barriers in the temperature range 800–1800 K for both vacancy types. Homogeneous strains as small as 2% have a considerable effect on diffusivity of both single and divacancies of uranium, with the effect of strain being more pronounced for single vacancies than divacancies. In contrast, the response of a given defect to strain is less sensitive to changes in the charge state of the defect. Further, strain leads to anisotropies in the mobility of the vacancy and the degree of anisotropy is very sensitive to the nature of the applied strain field for strain of equal magnitude. Our results indicate that the influence of strain on vacancy diffusivity will be significantly greater when single vacancies dominate the defect structure, such as sintering, while the effects will be much less substantial under irradiation conditions where divacancies dominate.« less

  3. Direct Numerical Simulations of the Diffusive Convection and Assessment of Its Impact on Artic Climate Change

    DTIC Science & Technology

    2007-09-01

    SPONSORING /MONITORING AGENCY NAME(S) AND ADDRESS(ES) N/A 10. SPONSORING/MONITORING AGENCY REPORT NUMBER 11 . SUPPLEMENTARY NOTES The views...panel) and eastern (right panel) Altantic Ocean. Adopted from You (2002).. 11 Figure 7. Same as Figure 4, but for Indian Ocean..........12 Figure 8...well developed field of two dimensional diffusive plumes after t= 50 . Note the well defined horizontal layers in the right figure after t=500. The

  4. Impact of homogeneous strain on uranium vacancy diffusion in uranium dioxide

    SciTech Connect

    Goyal, Anuj; Phillpot, Simon R.; Subramanian, Gopinath; Andersson, David A.; Stanek, Chris R.; Uberuaga, Blas P.

    2015-03-03

    We present a detailed mechanism of, and the effect of homogeneous strains on, the migration of uranium vacancies in UO2. Vacancy migration pathways and barriers are identified using density functional theory and the effect of uniform strain fields are accounted for using the dipole tensor approach. We report complex migration pathways and noncubic symmetry associated with the uranium vacancy in UO2 and show that these complexities need to be carefully accounted for to predict the correct diffusion behavior of uranium vacancies. We show that under homogeneous strain fields, only the dipole tensor of the saddle with respect to the minimum is required to correctly predict the change in the energy barrier between the strained and the unstrained case. Diffusivities are computed using kinetic Monte Carlo simulations for both neutral and fully charged state of uranium single and divacancies. We calculate the effect of strain on migration barriers in the temperature range 800–1800 K for both vacancy types. Homogeneous strains as small as 2% have a considerable effect on diffusivity of both single and divacancies of uranium, with the effect of strain being more pronounced for single vacancies than divacancies. In contrast, the response of a given defect to strain is less sensitive to changes in the charge state of the defect. Further, strain leads to anisotropies in the mobility of the vacancy and the degree of anisotropy is very sensitive to the nature of the applied strain field for strain of equal magnitude. Our results indicate that the influence of strain on vacancy diffusivity will be significantly greater when single vacancies dominate the defect structure, such as sintering, while the effects will be much less substantial under irradiation conditions where divacancies dominate.

  5. Impact of multi-component diffusion in turbulent combustion using direct numerical simulations

    DOE PAGES

    Bruno, Claudio; Sankaran, Vaidyanathan; Kolla, Hemanth; ...

    2015-08-28

    This study presents the results of DNS of a partially premixed turbulent syngas/air flame at atmospheric pressure. The objective was to assess the importance and possible effects of molecular transport on flame behavior and structure. To this purpose DNS were performed at with two proprietary DNS codes and with three different molecular diffusion transport models: fully multi-component, mixture averaged, and imposing the Lewis number of all species to be unity.

  6. Impact of multi-component diffusion in turbulent combustion using direct numerical simulations

    SciTech Connect

    Bruno, Claudio; Sankaran, Vaidyanathan; Kolla, Hemanth; Chen, Jacqueline H.

    2015-08-28

    This study presents the results of DNS of a partially premixed turbulent syngas/air flame at atmospheric pressure. The objective was to assess the importance and possible effects of molecular transport on flame behavior and structure. To this purpose DNS were performed at with two proprietary DNS codes and with three different molecular diffusion transport models: fully multi-component, mixture averaged, and imposing the Lewis number of all species to be unity.

  7. Impact of Information based Classification on Network Epidemics

    PubMed Central

    Mishra, Bimal Kumar; Haldar, Kaushik; Sinha, Durgesh Nandini

    2016-01-01

    Formulating mathematical models for accurate approximation of malicious propagation in a network is a difficult process because of our inherent lack of understanding of several underlying physical processes that intrinsically characterize the broader picture. The aim of this paper is to understand the impact of available information in the control of malicious network epidemics. A 1-n-n-1 type differential epidemic model is proposed, where the differentiality allows a symptom based classification. This is the first such attempt to add such a classification into the existing epidemic framework. The model is incorporated into a five class system called the DifEpGoss architecture. Analysis reveals an epidemic threshold, based on which the long-term behavior of the system is analyzed. In this work three real network datasets with 22002, 22469 and 22607 undirected edges respectively, are used. The datasets show that classification based prevention given in the model can have a good role in containing network epidemics. Further simulation based experiments are used with a three category classification of attack and defense strengths, which allows us to consider 27 different possibilities. These experiments further corroborate the utility of the proposed model. The paper concludes with several interesting results. PMID:27329348

  8. The Impact of Health Information Exchange on Health Outcomes

    PubMed Central

    Hincapie, A.; Warholak, T.

    2011-01-01

    Background and Objective Healthcare professionals, industry and policy makers have identified Health Information Exchange (HIE) as a solution to improve patient safety and overall quality of care. The potential benefits of HIE on healthcare have fostered its implementation and adoption in the United States. However,there is a dearth of publications that demonstrate HIE effectiveness. The purpose of this review was to identify and describe evidence of HIE impact on healthcare outcomes. Methods A database search was conducted. The inclusion criteria included original investigations in English that focused on a HIE outcome evaluation. Two independent investigators reviewed the articles. A qualitative coding approach was used to analyze the data. Results Out of 207 abstracts retrieved, five articles met the inclusion criteria. Of these, 3 were randomized controlled trials, 1 involved retrospective review of data, and 1 was a prospective study. We found that HIE benefits on healthcare outcomes are still sparsely evaluated, and that among the measurements used to evaluate HIE healthcare utilization is the most widely used. Conclusions Outcomes evaluation is required to give healthcare providers and policy-makers evidence to incorporate in decision-making processes. This review showed a dearth of HIE outcomes data in the published peer reviewed literature so more research in this area is needed. Future HIE evaluations with different levels of interoperability should incorporate a framework that allows a detailed examination of HIE outcomes that are likely to positively affect care. PMID:23616891

  9. Impact of Information based Classification on Network Epidemics

    NASA Astrophysics Data System (ADS)

    Mishra, Bimal Kumar; Haldar, Kaushik; Sinha, Durgesh Nandini

    2016-06-01

    Formulating mathematical models for accurate approximation of malicious propagation in a network is a difficult process because of our inherent lack of understanding of several underlying physical processes that intrinsically characterize the broader picture. The aim of this paper is to understand the impact of available information in the control of malicious network epidemics. A 1-n-n-1 type differential epidemic model is proposed, where the differentiality allows a symptom based classification. This is the first such attempt to add such a classification into the existing epidemic framework. The model is incorporated into a five class system called the DifEpGoss architecture. Analysis reveals an epidemic threshold, based on which the long-term behavior of the system is analyzed. In this work three real network datasets with 22002, 22469 and 22607 undirected edges respectively, are used. The datasets show that classification based prevention given in the model can have a good role in containing network epidemics. Further simulation based experiments are used with a three category classification of attack and defense strengths, which allows us to consider 27 different possibilities. These experiments further corroborate the utility of the proposed model. The paper concludes with several interesting results.

  10. Impacts of diffusive transport on carbonate mineral formation from magnesium silicate-CO2-water reactions.

    PubMed

    Giammar, Daniel E; Wang, Fei; Guo, Bin; Surface, J Andrew; Peters, Catherine A; Conradi, Mark S; Hayes, Sophia E

    2014-12-16

    Reactions of CO2 with magnesium silicate minerals to precipitate magnesium carbonates can result in stable carbon sequestration. This process can be employed in ex situ reactors or during geologic carbon sequestration in magnesium-rich formations. The reaction of aqueous CO2 with the magnesium silicate mineral forsterite was studied in systems with transport controlled by diffusion. The approach integrated bench-scale experiments, an in situ spectroscopic technique, and reactive transport modeling. Experiments were performed using a tube packed with forsterite and open at one end to a CO2-rich solution. The location and amounts of carbonate minerals that formed were determined by postexperiment characterization of the solids. Complementing this ex situ characterization, (13)C NMR spectroscopy tracked the inorganic carbon transport and speciation in situ. The data were compared with the output of reactive transport simulations that accounted for diffusive transport processes, aqueous speciation, and the forsterite dissolution rate. All three approaches found that the onset of magnesium carbonate precipitation was spatially localized about 1 cm from the opening of the forsterite bed. Magnesite was the dominant reaction product. Geochemical gradients that developed in the diffusion-limited zones led to locally supersaturated conditions at specific locations even while the volume-averaged properties of the system remained undersaturated.

  11. 41 CFR 60-3.4 - Information on impact.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... process does not have an adverse impact, the Federal enforcement agencies, in the exercise of their... impact, where they are significant in both statistical and practical terms or where a user's actions...

  12. 41 CFR 60-3.4 - Information on impact.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... process does not have an adverse impact, the Federal enforcement agencies, in the exercise of their... impact, where they are significant in both statistical and practical terms or where a user's actions...

  13. The impact of randomness on the distribution of wealth: Some economic aspects of the Wright-Fisher diffusion process

    NASA Astrophysics Data System (ADS)

    Bouleau, Nicolas; Chorro, Christophe

    2017-08-01

    In this paper we consider some elementary and fair zero-sum games of chance in order to study the impact of random effects on the wealth distribution of N interacting players. Even if an exhaustive analytical study of such games between many players may be tricky, numerical experiments highlight interesting asymptotic properties. In particular, we emphasize that randomness plays a key role in concentrating wealth in the extreme, in the hands of a single player. From a mathematical perspective, we interestingly adopt some diffusion limits for small and high-frequency transactions which are otherwise extensively used in population genetics. Finally, the impact of small tax rates on the preceding dynamics is discussed for several regulation mechanisms. We show that taxation of income is not sufficient to overcome this extreme concentration process in contrast to the uniform taxation of capital which stabilizes the economy and prevents agents from being ruined.

  14. The diffusion of computer-based information technology into health institutions of Republic of Serbia (FR Yugoslavia).

    PubMed

    Simić, S; Marinković, J; Bjegović, V; Stanisavljević, D

    1996-08-01

    The basic purpose of this study was to analyze the diffusion of computer-based information technology into the health care institutions of the Republic of Serbia in the year 1994, and to compare the results with a similar investigation in 1992 in order to determine the state and progress of its development. The instrument of investigation was a questionnaire with 24 questions, distributed to all the independent health institutions in Serbia (total 238). The overall response rate was 40.8%. Of the number of responding health institutions, 92.8% own computers which are in use, six PCs on average, and on average use two application softwares, obligatory one for accounting and billing. In conclusion, health care institutions in the Republic of Serbia are unsatisfactorily equipped with information technology and without the developed institutional information system, except on the level of the project. So, careful planning, selection, implementation and management with national coordination will be needed to ensure the appropriate use of technology and information systems in health care.

  15. A geographic information system screening tool to tackle diffuse pollution through the use of sustainable drainage systems.

    PubMed

    Todorovic, Zorica; Breton, Neil P

    2014-01-01

    Sustainable drainage systems (SUDS) offer many benefits that traditional solutions do not. Traditional approaches are unable to offer a solution to problems of flood management and water quality. Holistic consideration of the wide range of benefits from SUDS can result in advantages such as improved flood resilience and water quality enhancement through consideration of diffuse pollution sources. Using a geographical information system (GIS) approach, diffuse pollutant sources and opportunities for SUDS are easily identified. Consideration of potential SUDS locations results in source, site and regional controls, leading to improved water quality (to meet Water Framework Directive targets). The paper will discuss two different applications of the tool, the first of which is where the pollutant of interest is known. In this case the outputs of the tool highlight and isolate the areas contributing the pollutants and suggest the adequate SUDS measures to meet the required criteria. The second application is where the tool identifies likely pollutants at a receiving location, and SUDS measures are proposed to reduce pollution with assessed efficiencies.

  16. Real-Time Diffusion of Information on Twitter and the Financial Markets

    PubMed Central

    Tafti, Ali; Zotti, Ryan; Jank, Wolfgang

    2016-01-01

    Do spikes in Twitter chatter about a firm precede unusual stock market trading activity for that firm? If so, Twitter activity may provide useful information about impending financial market activity in real-time. We study the real-time relationship between chatter on Twitter and the stock trading volume of 96 firms listed on the Nasdaq 100, during 193 days of trading in the period from May 21, 2012 to September 18, 2013. We identify observations featuring firm-specific spikes in Twitter activity, and randomly assign each observation to a ten-minute increment matching on the firm and a number of repeating time indicators. We examine the extent that unusual levels of chatter on Twitter about a firm portend an oncoming surge of trading of its stock within the hour, over and above what would normally be expected for the stock for that time of day and day of week. We also compare the findings from our explanatory model to the predictive power of Tweets. Although we find a compelling and potentially informative real-time relationship between Twitter activity and trading volume, our forecasting exercise highlights how difficult it can be to make use of this information for monetary gain. PMID:27504639

  17. Real-Time Diffusion of Information on Twitter and the Financial Markets.

    PubMed

    Tafti, Ali; Zotti, Ryan; Jank, Wolfgang

    2016-01-01

    Do spikes in Twitter chatter about a firm precede unusual stock market trading activity for that firm? If so, Twitter activity may provide useful information about impending financial market activity in real-time. We study the real-time relationship between chatter on Twitter and the stock trading volume of 96 firms listed on the Nasdaq 100, during 193 days of trading in the period from May 21, 2012 to September 18, 2013. We identify observations featuring firm-specific spikes in Twitter activity, and randomly assign each observation to a ten-minute increment matching on the firm and a number of repeating time indicators. We examine the extent that unusual levels of chatter on Twitter about a firm portend an oncoming surge of trading of its stock within the hour, over and above what would normally be expected for the stock for that time of day and day of week. We also compare the findings from our explanatory model to the predictive power of Tweets. Although we find a compelling and potentially informative real-time relationship between Twitter activity and trading volume, our forecasting exercise highlights how difficult it can be to make use of this information for monetary gain.

  18. 76 FR 58240 - Modoc National Forest, Alturas, CA, Supplemental Information for the Final Environmental Impact...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-09-20

    ... Forest Service Modoc National Forest, Alturas, CA, Supplemental Information for the Final Environmental Impact Statement (FEIS) Motorized Travel Management AGENCY: Forest Service, USDA. ACTION: Notice of intent to supplement the Modoc National Forest Motorized Travel Management Final Environmental Impact...

  19. Diffusion of personal health information services: self-determining and empowering practices for Manitoba Inuit.

    PubMed

    Clark, Wayne Voisey

    2014-01-01

    This article highlights findings from research conducted with the Manitoba Urban Inuit Association with regard to culturally safe practices for communicating personal health information services related to a provincial integrated electronic health record. By applying a "two-eyed seeing research approach," which incorporates traditional and Western scientific perspectives, the author describes Inuit cultural considerations when communicating electronic health concepts with a vision of advancing toward program evaluation opportunities. The research is supported by two Inuit-driven focus groups, interviews with three jurisdictional representatives of electronic health program delivery agencies and one interview with an Inuk elder.

  20. Prognostic impact of the 2016 WHO classification of diffuse gliomas in the French POLA cohort.

    PubMed

    Tabouret, Emeline; Nguyen, Anh Tuan; Dehais, Caroline; Carpentier, Catherine; Ducray, François; Idbaih, Ahmed; Mokhtari, Karima; Jouvet, Anne; Uro-Coste, Emmanuelle; Colin, Carole; Chinot, Olivier; Loiseau, Hugues; Moyal, Elisabeth; Maurage, Claude-Alain; Polivka, Marc; Lechapt-Zalcman, Emmanuèle; Desenclos, Christine; Meyronet, David; Delattre, Jean-Yves; Figarella-Branger, Dominique

    2016-10-01

    The new WHO classification of diffuse gliomas has been refined and now includes the 1p/19q codeletion, IDH1/2 mutation, and histone H3-K27M mutation. Our objective was to assess the prognostic value of the updated 2016 WHO classification in the French POLA cohort. All cases of high-grade oligodendroglial tumors sent for central pathological review and included into the French nationwide POLA cohort were reclassified according to the updated 4th WHO classification. In total, 1041 patients were included, with a median age at diagnosis of 50.4 years (range 17.1-84.4). Based on the new histomolecular classification, diagnoses included anaplastic oligodendroglioma IDH mutant and 1p/19q-codeleted (32.5 %), anaplastic astrocytoma IDH mutant (IDH (mut)) (11.0 %), anaplastic astrocytoma IDH wild type (IDH (wt)) (5.3 %), glioblastoma IDH (mut) (17.1 %), and glioblastoma IDH (wt) (33.2 %). Ten patients presented with a diffuse midline tumor, H3 K27M mutant. The new WHO classification was prognostic for progression-free survival (PFS) and overall survival (OS) (p < 0.001). We did not find prognosis differences between grades III and IV for IDH (mut) 1p/19q intact and IDH (wt) gliomas in univariate and multivariate analyses. Among anaplastic astrocytoma IDH (wt), cases with chromosome arm 7p gain and 10q loss (55 %) had shorter PFS than the others (p = 0.027). In conclusion, the new WHO histomolecular classification of diffuse gliomas presented with high prognostic value. Grading was not discriminant between grade III and IV high-grade gliomas.

  1. Constraints on thermal histories of magmas from combined U-series crystal ages, trace-element diffusion, and textural information

    NASA Astrophysics Data System (ADS)

    Cooper, K. M.; Kent, A. J.

    2012-12-01

    Developing a better understanding of the thermal and chemical evolution of magmas within crustal reservoirs has implications both in terms of the mechanisms of generation of chemically diverse magmas and in terms of the development, size and longevity of bodies of eruptible magma. The physical and thermal states of the system are intimately linked, going from mostly liquid to mushy to potentially solid or almost-solid systems as a function largely of temperature. Crystal-scale records show evidence of long-term storage and recycling of crystals within a reservoir system, but the extent to which storage of these antecrysts occurs in mostly-liquid vs. mostly-solid or solid bodies is unclear. Numerical models can provide insights into thermal histories at a reservoir scale, and crystal and liquid thermometry can provide insights into the thermal state of the crystals at snapshots in time, but developing thermal histories from the record in erupted products has been elusive. We present a new approach to quantifying thermal histories of magma bodies using the crystal record by combining information from multiple analytical approaches. U-series crystal ages provide the total time since crystals grew (albeit averaged). In contrast, trace-element zoning provides an uppper limit to the duration of storage at high temperatures, and crystal sizes and CSDs provide insights into the total growth time of crystals (modified by dissolution). Thus, by combining information from all of these sources, we can link the crystal growth and diffusion ages to thermal states and therefore constrain thermal histories. We use recent eruptive products at Mt Hood as a case study, building off of previous 238U-230Th-226Ra crystal age, CSD, and diffusion modeling results. 230Th-226Ra ages of crystals from the silicic endmember of the most recent Mt Hood eruptions both have average ages of >4.5 ka and likely have cores with ages >10 ka (Eppich et al., EPSL, 2012 v. 317-318). Diffusion of Sr in

  2. R&D Advancement, Technology Diffusion, and Impact on Evaluation of Public R&D

    SciTech Connect

    Moore, M. C.; Arent, D. J.; Norland, D.

    2005-01-01

    In a 2001 report titled "Research at DOE: Was It Worth It?", a National Research Council (NRC) committee defined a set of simplifying rules to estimate the net economic benefits from technologies supported by the Department of Energy (DOE). This NREL paper evaluates the efficacy of the NRC rules compared to published literature on acceleration of technology introduction into markets, technology diffusion, and infrastructure change. It also offers considerations for revisions of the rules that call for the use of technology and sector-specific data, advanced forecasting techniques, and sensitivity analysis to test the robustness of the methodology.

  3. Reconstruction algorithm for diffuse optical tomography using x-ray CT anatomical information and application to bioluminescence tomography

    NASA Astrophysics Data System (ADS)

    Naser, Mohamed A.; Pekar, Julius; Patterson, Michael S.

    2011-02-01

    An algorithm to solve the diffuse optical tomography (DOT) problem is described which uses the anatomical information from x-ray CT images. These provide a priori information about the distribution of the optical properties hence reducing the number of variables and permitting a unique solution to the ill-posed problem. The light fluence rate at the boundary is written as a Taylor series expansion around an initial guess corresponding to an optically homogenous object. The second order approximation is considered and the derivatives are calculated by direct methods. These are used in an iterative algorithm to reconstruct the tissue optical properties. The reconstructed optical properties are then used for bioluminescence tomography where a minimization problem is formed based on the L1 norm objective function which uses normalized values for the light fluence rates and the corresponding Green's functions. Then an iterative minimization solution shrinks the permissible regions where the sources are allowed by selecting points with higher probability to contribute to the source distribution. Throughout this process the permissible region shrinks from the entire object to just a few points. The optimum reconstructed bioluminescence distributions are chosen to be the results of the iteration corresponding to the permissible region where the objective function has its global minimum. This provides efficient BLT reconstruction algorithms without the need for a priori information about the bioluminescence sources.

  4. 40Ar/39Ar impact ages and time-temperature argon diffusion history of the Bunburra Rockhole anomalous basaltic achondrite

    NASA Astrophysics Data System (ADS)

    Jourdan, Fred; Benedix, Gretchen; Eroglu, Ela.; Bland, Phil. A.; Bouvier, Audrey.

    2014-09-01

    The Bunburra Rockhole meteorite is a brecciated anomalous basaltic achondrite containing coarse-, medium- and fine-grained lithologies. Petrographic observations constrain the limited shock pressure to between ca. 10 GPa and 20 GPa. In this study, we carried out nine 40Ar/39Ar step-heating experiments on distinct single-grain fragments extracted from the coarse and fine lithologies. We obtained six plateau ages and three mini-plateau ages. These ages fall into two internally concordant populations with mean ages of 3640 ± 21 Ma (n = 7; P = 0.53) and 3544 ± 26 Ma (n = 2; P = 0.54), respectively. Based on these results, additional 40Ar/39Ar data of fusion crust fragments, argon diffusion modelling, and petrographic observations, we conclude that the principal components of the Bunburra Rockhole basaltic achondrite are from a melt rock formed at ∼3.64 Ga by a medium to large impact event. The data imply that this impact generated high enough energy to completely melt the basaltic target rock and reset the Ar systematics, but only partially reset the Pb-Pb age. We also conclude that a complete 40Ar∗ resetting of pyroxene and plagioclase at this time could not have been achieved at solid-state conditions. Comparison with a terrestrial analog (Lonar crater) shows that the time-temperature conditions required to melt basaltic target rocks upon impact are relatively easy to achieve. Ar data also suggest that a second medium-size impact event occurred on a neighbouring part of the same target rock at ∼3.54 Ga. Concordant low-temperature step ages of the nine aliquots suggest that, at ∼3.42 Ga, a third smaller impact excavated parts of the ∼3.64 Ga and ∼3.54 Ga melt rocks and brought the fragments together. The lack of significant impact activity after 3.5 Ga, as recorded by the Bunburra Rockhole suggests that (1) either the meteorite was ejected in a small secondary parent body where it resided untouched by large impacts, or (2) it was covered by a porous heat

  5. Diffuse and point pollution impacts on the pathogen indicator organism level in the Geum River, Korea.

    PubMed

    Kim, Geonha; Choi, Euiso; Lee, Dongryul

    2005-11-01

    The pathogens originating from diffuse pollution have raised much concern recently. In many countries, pathogen levels are monitored in surface water by measuring the pathogen indicator organism level, which indicates the concentration of pathogen associated microorganisms to determine contamination. Among indicator organisms, total coliform, fecal coliform, and Escherichia coli were selected for study, and their concentration as well as their flow rate were monitored at monitoring stations from October, 2001 to April, 2003. Monitoring stations include six sampling stations in the Geum River, two small watersheds used for forestry and agricultural land, one large wastewater treatment plant, one separate sewer overflow site, and one separate sewer overflow site in the Geum River basin. The coliform concentration of the combined sewer overflow was the highest, followed by the runoff from agricultural land use, the separate sewer overflow, and the runoff from forestry land use. The Pearson correlation coefficient for flow rate against total coliform concentration was 0.71 and was significant at 0.01 level, while the Pearson coefficient for other water quality constituents showed weak correlation (-0.36 to +0.37) against flow rate. Coliform concentration showed higher correlation against suspended solid concentration or flow rate during storm flow condition than during low flow condition. Two different relationship lines could explain the relationships between the flow rate and coliform loadings. Load duration curve technique was presented to assess the relative contributions of diffuse and point source pollution to the pathogen level at monitoring sites in the Geum River.

  6. Air Quality Impact of Diffuse and Inefficient Combustion Emissions in Africa (DICE-Africa).

    PubMed

    Marais, Eloise A; Wiedinmyer, Christine

    2016-10-04

    Anthropogenic pollution in Africa is dominated by diffuse and inefficient combustion sources, as electricity access is low and motorcycles and outdated cars proliferate. These sources are missing, out-of-date, or misrepresented in state-of-the-science emission inventories. We address these deficiencies with a detailed inventory of Diffuse and Inefficient Combustion Emissions in Africa (DICE-Africa) for 2006 and 2013. Fuelwood for energy is the largest emission source in DICE-Africa, but grows from 2006 to 2013 at a slower rate than charcoal production and use, and gasoline and diesel for motorcycles, cars, and generators. Only kerosene use and gas flaring decline. Increase in emissions from 2006 to 2013 in this work is consistent with trends in satellite observations of formaldehyde and NO2, but much slower than the explosive growth projected with a fuel consumption model. Seasonal biomass burning is considered a large pollution source in Africa, but we estimate comparable emissions of black carbon and higher emissions of nonmethane volatile organic compounds from DICE-Africa. Nitrogen oxide (NOx ≡ NO + NO2) emissions are much lower than from biomass burning. We use GEOS-Chem to estimate that the largest contribution of DICE-Africa to annual mean surface fine particulate matter (PM2.5) is >5 μg m(-3) in populous Nigeria.

  7. Impact of mesophyll diffusion on estimated global land CO2 fertilization

    SciTech Connect

    Sun, Ying; Gu, Lianhong; Dickinson, Robert E.; Norby, Richard J.; Pallardy, Stephen G.; Hoffman, Forrest M.

    2014-10-13

    In C3 plants, CO2 concentrations drop considerably along mesophyll diffusion pathways from substomatal cavities to chloroplasts where CO2 assimilation occurs. Global carbon cycle models have not explicitly represented this internal drawdown and so overestimate CO2 available for carboxylation and underestimate photosynthetic responsiveness to atmospheric CO2. An explicit consideration of mesophyll diffusion increases the modeled cumulative CO2 fertilization effect (CFE) for global gross primary production (GPP) from 915 PgC to 1057 PgC for the period of 1901 to 2010. This increase represents a 16% correction, large enough to explain the persistent overestimation of growth rates of historical atmospheric CO2 by Earth System Models. Without this correction, the CFE for global GPP is underestimated by 0.05 PgC yr-1ppm-1. This finding implies that the contemporary terrestrial biosphere is more CO2-limited than previously thought.

  8. Working memory training impacts the mean diffusivity in the dopaminergic system.

    PubMed

    Takeuchi, Hikaru; Taki, Yasuyuki; Nouchi, Rui; Hashizume, Hiroshi; Sekiguchi, Atsushi; Kotozaki, Yuka; Nakagawa, Seishu; Miyauchi, Carlos Makoto; Sassa, Yuko; Kawashima, Ryuta

    2015-11-01

    Dopaminergic transmission plays a critical role in working memory (WM). Mean diffusivity (MD) is a sensitive and unique neuroimaging tool for detecting microstructural differences particularly in the areas of the dopaminergic system. Despite previous investigation of the effects of WM training (WMT) on dopamine receptor binding potentials, the effects of WMT on MD remain unknown. In this study, we investigated these effects in young adult subjects who either underwent WMT or received no intervention for 4 weeks. Before and after the intervention or no-intervention periods, subjects underwent scanning sessions in diffusion-weighted imaging to measure MD. Compared with no intervention, WMT resulted in an increase in MD in the bilateral caudate, right putamen, left dorsolateral prefrontal cortex (DLPFC), right anterior cingulate cortex (ACC), right substantia nigra, and ventral tegmental area. Furthermore, the increase in performance on WMT tasks was significantly positively correlated with the mean increase in MD in the clusters of the left DLPFC and of the right ACC. These results suggest that WMT caused microstructural changes in the regions of the dopaminergic system in a way that is usually interpreted as a reduction in neural components.

  9. NASA/DOD Aerospace Knowledge Diffusion Research Project. Paper 57; US Scientific and Technical Information Policy

    NASA Technical Reports Server (NTRS)

    Pinelli, Thomas E.; Barclay, Rebecca O.; Kennedy, John M.

    1996-01-01

    In fiscal year 1994, the United States government spent about $68 billion for science and technology. Although there is general agreement among policy makers that the results of this expenditure can be used to enhance technological innovation and improve economic competitiveness, there is no coherent scientific and technical information (STI) policy. The absence of a cohesive policy and STI policy framework means that the transfer and utilization of STI goes uncoordinated. This chapter examines the U.S. government's role in funding science and technology, reviews Federal STI activities and involvement in the transfer and use of STI resulting from federally-funded science and technology, presents issues surrounding the use of federally-funded STI, and offers recommendations for improving the transfer and use of STI.

  10. Frequency and impact of informant replacement in Alzheimer disease research.

    PubMed

    Grill, Joshua D; Zhou, Yan; Karlawish, Jason; Elashoff, David

    2015-01-01

    Informants serve an essential role in Alzheimer disease research. Were an informant to be replaced during a longitudinal study, this could have negative implications. We used data from the National Alzheimer's Coordinating Center Uniform Data Set to examine the frequency of informant replacement among Alzheimer disease dementia participants, whether patient and informant characteristics were associated with replacement, and how replacement affected research outcome measures. Informant replacement was common (15.5%) and typically occurred after the first or the second research visit. Adult child (24%) and other (38%) informants were more frequently replaced than spouse informants (10%). Older spouse informant age and younger adult child informant age were associated with replacement. The between-visit change in Functional Assessment Questionnaire scores was greater in patients who replaced informants than in those with stable informants. Clinical Dementia Rating-Sum of Boxes, Functional Assessment Questionnaire, and Neuropsychiatric Inventory scores showed greater variability in between-visit change in patients who replaced informants compared with those with stable informants. These findings suggest that informant replacement is relatively common, may have implications to study analyses, and warrant further examination in the setting of clinical trials.

  11. Information geometry of q-Gaussian densities and behaviors of solutions to related diffusion equations

    NASA Astrophysics Data System (ADS)

    Ohara, Atsumi; Wada, Tatsuaki

    2010-01-01

    This paper presents new geometric aspects of the behaviors of solutions to the porous medium equation (PME) and its associated equation. First we discuss thermostatistical structure with information geometry on a manifold of generalized exponential densities. A dualistic relation between the two existing formalisms is elucidated. Next by equipping the manifold of q-Gaussian densities with such a structure, we derive several physically and geometrically interesting properties of the solutions. The manifold is proved invariant and attracting for the evolving solutions, which play crucial roles in our analysis. We demonstrate that the moment-conserving projection of a solution coincides with a geodesic curve on the manifold. Further, the evolutional velocities of the second moments and the convergence rate to the manifold are evaluated in terms of the Bregman divergence. Finally we show that the self-similar solution is geometrically special in the sense that it is simultaneously geodesic with respect to the mutually dual two affine connections. Preliminary forms of several results in this paper will appear in [50] without proofs.

  12. The diffusion of maize to the southwestern United States and its impact

    PubMed Central

    Merrill, William L.; Hard, Robert J.; Mabry, Jonathan B.; Fritz, Gayle J.; Adams, Karen R.; Roney, John R.; MacWilliams, A. C.

    2009-01-01

    Our understanding of the initial period of agriculture in the southwestern United States has been transformed by recent discoveries that establish the presence of maize there by 2100 cal. B.C. (calibrated calendrical years before the Christian era) and document the processes by which it was integrated into local foraging economies. Here we review archaeological, paleoecological, linguistic, and genetic data to evaluate the hypothesis that Proto-Uto-Aztecan (PUA) farmers migrating from a homeland in Mesoamerica introduced maize agriculture to the region. We conclude that this hypothesis is untenable and that the available data indicate instead a Great Basin homeland for the PUA, the breakup of this speech community into northern and southern divisions ≈6900 cal. B.C. and the dispersal of maize agriculture from Mesoamerica to the US Southwest via group-to-group diffusion across a Southern Uto-Aztecan linguistic continuum. PMID:19995985

  13. Triple line diffusion in nanocrystalline Fe/Cr and its impact on thermal stability.

    PubMed

    Stender, Patrick; Balogh, Zoltan; Schmitz, Guido

    2011-05-01

    The thermal reaction of iron-chromium multilayers is analyzed by atom-probe tomography. Samples were prepared using ion-beam sputter deposition and cutting by focused ion beams. Isothermal and isochronal annealing sequences were carried out in a vacuum furnace. Effects of atomic transport are observed at temperatures above 773 K. Segregation along line-shaped zones is noticed to very high concentrations. These zones, with a diameter of 1.5 nm, are identified as triple lines of the grain structure. While these defects could not be resolved by TEM, the outstanding potential of a 3D analysis provided by APT allowed their detailed investigation. Evaluating the dependence of the segregation amplitude on time and temperature, the segregation enthalpy and diffusivity of the triple lines are quantified. The segregation enthalpy is determined to be 0.076 eV, which indicates the considerable excess volume at the triple line.

  14. [IMPACT ON DIFFERENTIATED THERAPY OF SOMATIC AND SEXUAL DEVELOPMENT OF ADOLESCENTS WITH DIFFUSE NONTOXIC GOITER].

    PubMed

    Turchina, S I

    2015-01-01

    Results of complex inspection of 163 girls and 192 boys of 8-17 years with the diffusion not toxic craw (DNG) are presented. At 59.4% of patients revealed disharmonious physical development. Most often defined deficiency of weight of a body (37.5%) and/or low growth (28.0%). The delay of sexual development which practically at all adolescents (83.8%) was accompanied by deficiency of weight of a body and low growth is diagnosed for 32.8% of adolescents boys and 8.3% of girls. The necessity of a differentiated approach to the treatment of adolescents with a poor prognosis of DOP. The use of the. proposed technology improves the efficiency of treatment to 77.4% after 6 months and 86.3% at 12 months, as well as improve overall health outcomes and somatopolovogo development.

  15. Privatization of Public Information: Its Impact on Libraries.

    ERIC Educational Resources Information Center

    Shill, Harold B.

    1991-01-01

    Explores the ideas and policies behind the movement toward privatization, and traces the history of information privatization during the Reagan administration. A discussion of privatization of government information focuses on attempts to privatize NTIS (National Technical Information Service), and differences between print and electronic…

  16. Privatization of Public Information: Its Impact on Libraries.

    ERIC Educational Resources Information Center

    Shill, Harold B.

    1991-01-01

    Explores the ideas and policies behind the movement toward privatization, and traces the history of information privatization during the Reagan administration. A discussion of privatization of government information focuses on attempts to privatize NTIS (National Technical Information Service), and differences between print and electronic…

  17. Wear resistance of diffusion coatings on the working parts of impact-rebound crushers

    SciTech Connect

    Nedzel'skii, M.D.; Katkov, Y.K.

    1984-01-01

    Impact-rebound crushers used in the chemical industry suffer intensive wear of the crusher blades when crushing materials like quartz sand, corundum, and diabase. A special impact-rebound crushers has been made for testing the wear resistance of hardened prototype blades, andi it is described in detail in this paper. Tests were done to determine the most effective methods of surface hardening for the replaceable inserts made of readily available steel and it is found that the carbonitriding of steel gives a hardened layer to increase the wear resistance of the crusher body and rotor surfaces.

  18. Time-resolved diffuse optical tomographic imaging for the provision of both anatomical and functional information about biological tissue

    NASA Astrophysics Data System (ADS)

    Zhao, Huijuan; Gao, Feng; Tanikawa, Yukari; Homma, Kazuhiro; Yamada, Yukio

    2005-04-01

    We present in vivo images of near-infrared (NIR) diffuse optical tomography (DOT) of human lower legs and forearm to validate the dual functions of a time-resolved (TR) NIR DOT in clinical diagnosis, i.e., to provide anatomical and functional information simultaneously. The NIR DOT system is composed of time-correlated single-photon-counting channels, and the image reconstruction algorithm is based on the modified generalized pulsed spectral technique, which effectively incorporates the TR data with reasonable computation time. The reconstructed scattering images of both the lower legs and the forearm revealed their anatomies, in which the bones were clearly distinguished from the muscles. In the absorption images, some of the blood vessels were observable. In the functional imaging, a subject was requested to do handgripping exercise to stimulate physiological changes in the forearm tissue. The images of oxyhemoglobin, deoxyhemoglobin, and total hemoglobin concentration changes in the forearm were obtained from the differential images of the absorption at three wavelengths between the exercise and the rest states, which were reconstructed with a differential imaging scheme. These images showed increases in both blood volume and oxyhemoglobin concentration in the arteries and simultaneously showed hypoxia in the corresponding muscles. All the results have demonstrated the capability of TR NIR DOT by reconstruction of the absolute images of the scattering and the absorption with a high spatial resolution that finally provided both the anatomical and functional information inside bulky biological tissues.

  19. Untangling a crystal storm through time: how do 500 diffusion stopwatches inform our view of Eyjafjallajökull 2010?

    NASA Astrophysics Data System (ADS)

    Pankhurst, M. J.; Morgan, D. J.; Thordarson, T.; Loughlin, S.

    2014-12-01

    A new database of 500+ olivine crystal timescales from samples that encompass the duration of the 2010 Fimmvörðuháls-Eyjafjallajökull eruption is presented. We also integrate new petrologic, thermometric and barometric data to read a 4D narrative of the magmatic processes within this volcanic plumbing system preceding­­- and during- eruption. Using this perspective we can identify and semi-quantify magmatic componentry, detect new magmatic inputs, and 'watch' those crystal chemical populations age. We find that major crystal-liquid disequilibrium events occurred up to several years preceding the eruptions, and inputs fed the plumbing system during the eruption window (days - hours). We place timeframes upon processes including magma-mixing, mush remobilization and erosion, and final-ascent quenching and eruption. Fe-Mg binary diffusion in olivine modelling conducted upon this scale was made possible using new advances -also presented here- in both the gathering and processing of raw data, and extraction of timescale information. We demonstrate that this streamlined workflow can now produce statistically robust timescale data within an integrated petrologic and geochemical context that may be resolved alongside independent geophysical and other remote sensing data into a common dimension - time. Transposing petrologic information (record of past process) and geophysical observation (phenomenological in the present) into a common language is designed to produce new understanding of both active and palaeo- volcanic systems, the implications of which we discuss here using our case study as an example.

  20. The Impact of Information Culture on Patient Safety Outcomes

    PubMed Central

    Mikkonen, Santtu; Saranto, Kaija; Bates, David W.

    2017-01-01

    Summary Background An organization’s information culture and information management practices create conditions for processing patient information in hospitals. Information management incidents are failures that could lead to adverse events for the patient if they are not detected. Objectives To test a theoretical model that links information culture in acute care hospitals to information management incidents and patient safety outcomes. Methods Reason’s model for the stages of development of organizational accidents was applied. Study data were collected from a cross-sectional survey of 909 RNs who work in medical or surgical units at 32 acute care hospitals in Finland. Structural equation modeling was used to assess how well the hypothesized model fit the study data. Results Fit indices indicated a good fit for the model. In total, 18 of the 32 paths tested were statistically significant. Documentation errors had the strongest total effect on patient safety outcomes. Organizational guidance positively affected information availability and utilization of electronic patient records, whereas the latter had the strongest total effect on the reduction of information delays. Conclusions Patient safety outcomes are associated with information management incidents and information culture. Further, the dimensions of the information culture create work conditions that generate errors in hospitals. PMID:28272647

  1. Some Probable Technological Trends and Their Impact on an Information Network System. LINCS Project Document Series.

    ERIC Educational Resources Information Center

    Ebersole, Joseph L.

    Improvements in the technology associated with the information sciences will have their primary potential impact on the distribution of costs, information flow level, information availability, and use among information channels. This improvement implied not only a capability to perform a given function, but a lower cost. For example, the trend…

  2. Final environmental impact assessment of the Paducah Gaseous Diffusion Plant site, Paducah, Kentucky

    SciTech Connect

    Not Available

    1982-08-01

    This document considers: the need for uranium enrichment facilities; site location; plant description; and describes the power generating facilities in light of its existing environment. The impacts from continuing operations are compared with alternatives of shutdown, relocation, and alternative power systems. (PSB)

  3. Impact of Modified Anisotropic Diffusion-based Enhancement Method in Computer-Aided Classification of Focal Liver Lesions.

    PubMed

    Mittal, Deepti

    2017-03-01

    This work is presented with the objective to assess quantitatively the impact of modified anisotropic diffusion-based enhancement method of Mittal et al. in computer-aided classification of focal liver lesions. This assessment was made before and after enhancement of clinically acquired ultrasound images with the comparison of (a) discrimination capability of radiologically important texture contrast feature using box plot and p-value statistics and (b) test results of designed computer-aided classification schemes to detect/classify focal liver tissues using receiver operating characteristic curves. The results reveal that the application of enhancement method on clinically acquired ultrasound image may effectively improve the confidence of clinicians/radiologists in computer-aided diagnostic solutions to detect and classify focal liver lesions.

  4. Integration of acoustical information in the perception of impacted sound sources: the role of information accuracy and exploitability.

    PubMed

    Giordano, Bruno L; Rocchesso, Davide; McAdams, Stephen

    2010-04-01

    Sound sources are perceived by integrating information from multiple acoustical features. The factors influencing the integration of information are largely unknown. We measured how the perceptual weighting of different features varies with the accuracy of information and with a listener's ability to exploit it. Participants judged the hardness of two objects whose interaction generates an impact sound: a hammer and a sounding object. In a first discrimination experiment, trained listeners focused on the most accurate information, although with greater difficulty when perceiving the hammer. We inferred a limited exploitability for the most accurate hammer-hardness information. In a second rating experiment, listeners focused on the most accurate information only when estimating sounding-object hardness. In a third rating experiment, we synthesized sounds by independently manipulating source properties that covaried in Experiments 1 and 2: sounding-object hardness and impact properties. Sounding-object hardness perception relied on the most accurate acoustical information, whereas impact-properties influenced more strongly hammer hardness perception. Overall, perceptual weight increased with the accuracy of acoustical information, although information that was not easily exploited was perceptually secondary, even if accurate.

  5. Impact of Confinement and Interfaces on Glass Transition Temperature, Fragility and Small Molecule Diffusivity in Polymers

    NASA Astrophysics Data System (ADS)

    Lan, Tian

    observed. When the effect of confinement on fragility increases by employing linear polymer with a higher value of m bulk, the effect of confinement on Tg also increases. When the effect of confinement on fragility is negligible, as with dense PS brushes, it is also negligible on Tg. The effect of confinement on translational diffusion of small-molecule tracers was studied in thin PS films using fluorescence spectroscopy via a Forster resonance energy transfer (FRET) process or an acid-enhanced fluorescence process. Tracers included an organic dye molecule 9,10-bis(phenylethynyl) anthracene (BPEA) and an organic acid p-toluenesulfonic acid monohydrate (pTSA), the latter of potential use in lithography. Substantial reductions in diffusivity were observed with both BPEA and pTSA. For example, the BPEA diffusivity was reduced by 80 - 90% in a 100-nm-thick PS film compared to that in bulk-like PS films, when measured close to Tg.

  6. The diffusion of microfinance.

    PubMed

    Banerjee, Abhijit; Chandrasekhar, Arun G; Duflo, Esther; Jackson, Matthew O

    2013-07-26

    To study the impact of the choice of injection points in the diffusion of a new product in a society, we developed a model of word-of-mouth diffusion and then applied it to data on social networks and participation in a newly available microfinance loan program in 43 Indian villages. Our model allows us to distinguish information passing among neighbors from direct influence of neighbors' participation decisions, as well as information passing by participants versus nonparticipants. The model estimates suggest that participants are seven times as likely to pass information compared to informed nonparticipants, but information passed by nonparticipants still accounts for roughly one-third of eventual participation. An informed household is not more likely to participate if its informed friends participate. We then propose two new measures of how effective a given household would be as an injection point. We show that the centrality of the injection points according to these measures constitutes a strong and significant predictor of eventual village-level participation.

  7. 78 FR 79475 - 30-Day Notice of Proposed Information Collection: The Impact of Housing and Services...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-12-30

    ... Interventions on Homeless Families--36-Month Follow-Up Data Collection AGENCY: Office of the Chief Information... Title of Information Collection: The Impact of Housing and Services Interventions on Homeless Families... Options Study, formerly referred to as The Impact of Housing and Services Interventions on Homeless...

  8. A Potential Value of Familiarity and Experience: Can Informal Fieldwork Have a Lasting Impact upon Literacy?

    ERIC Educational Resources Information Center

    Scott, Graham W.; Boyd, Margaret

    2014-01-01

    This paper demonstrates that an informal field trip can have a lasting impact upon aspects of learning in a primary school context. Specifically, we consider the longer term impact of an informal trip to a rocky shore upon scores achieved in literacy assessments taking place five months after a relevant five months after a fieldwork. Pupils…

  9. A Potential Value of Familiarity and Experience: Can Informal Fieldwork Have a Lasting Impact upon Literacy?

    ERIC Educational Resources Information Center

    Scott, Graham W.; Boyd, Margaret

    2014-01-01

    This paper demonstrates that an informal field trip can have a lasting impact upon aspects of learning in a primary school context. Specifically, we consider the longer term impact of an informal trip to a rocky shore upon scores achieved in literacy assessments taking place five months after a relevant five months after a fieldwork. Pupils…

  10. Mapping physician Twitter networks: describing how they work as a first step in understanding connectivity, information flow, and message diffusion.

    PubMed

    Mishori, Ranit; Singh, Lisa Oberoi; Levy, Brendan; Newport, Calvin

    2014-04-14

    Twitter is becoming an important tool in medicine, but there is little information on Twitter metrics. In order to recommend best practices for information dissemination and diffusion, it is important to first study and analyze the networks. This study describes the characteristics of four medical networks, analyzes their theoretical dissemination potential, their actual dissemination, and the propagation and distribution of tweets. Open Twitter data was used to characterize four networks: the American Medical Association (AMA), the American Academy of Family Physicians (AAFP), the American Academy of Pediatrics (AAP), and the American College of Physicians (ACP). Data were collected between July 2012 and September 2012. Visualization was used to understand the follower overlap between the groups. Actual flow of the tweets for each group was assessed. Tweets were examined using Topsy, a Twitter data aggregator. The theoretical information dissemination potential for the groups is large. A collective community is emerging, where large percentages of individuals are following more than one of the groups. The overlap across groups is small, indicating a limited amount of community cohesion and cross-fertilization. The AMA followers' network is not as active as the other networks. The AMA posted the largest number of tweets while the AAP posted the fewest. The number of retweets for each organization was low indicating dissemination that is far below its potential. To increase the dissemination potential, medical groups should develop a more cohesive community of shared followers. Tweet content must be engaging to provide a hook for retweeting and reaching potential audience. Next steps call for content analysis, assessment of the behavior and actions of the messengers and the recipients, and a larger-scale study that considers other medical groups using Twitter.

  11. Pathways for best practice diffusion: the structure of informal relationships in Canada's long-term care sector.

    PubMed

    Dearing, James W; Beacom, Amanda M; Chamberlain, Stephanie A; Meng, Jingbo; Berta, Whitney B; Keefe, Janice M; Squires, Janet E; Doupe, Malcolm B; Taylor, Deanne; Reid, Robert Colin; Cook, Heather; Cummings, Greta G; Baumbusch, Jennifer L; Knopp-Sihota, Jennifer; Norton, Peter G; Estabrooks, Carole A

    2017-02-03

    Initiatives to accelerate the adoption and implementation of evidence-based practices benefit from an association with influential individuals and organizations. When opinion leaders advocate or adopt a best practice, others adopt too, resulting in diffusion. We sought to identify existing influence throughout Canada's long-term care sector and the extent to which informal advice-seeking relationships tie the sector together as a network. We conducted a sociometric survey of senior leaders in 958 long-term care facilities operating in 11 of Canada's 13 provinces and territories. We used an integrated knowledge translation approach to involve knowledge users in planning and administering the survey and in analyzing and interpreting the results. Responses from 482 senior leaders generated the names of 794 individuals and 587 organizations as sources of advice for improving resident care in long-term care facilities. A single advice-seeking network appears to span the nation. Proximity exhibits a strong effect on network structure, with provincial inter-organizational networks having more connections and thus a denser structure than interpersonal networks. We found credible individuals and organizations within groups (opinion leaders and opinion-leading organizations) and individuals and organizations that function as weak ties across groups (boundary spanners and bridges) for all studied provinces and territories. A good deal of influence in the Canadian long-term care sector rests with professionals such as provincial health administrators not employed in long-term care facilities. The Canadian long-term care sector is tied together through informal advice-seeking relationships that have given rise to an emergent network structure. Knowledge of this structure and engagement with its opinion leaders and boundary spanners may provide a route for stimulating the adoption and effective implementation of best practices, improving resident care and strengthening the long

  12. Impact of one-layer assumption on diffuse reflectance spectroscopy of skin.

    PubMed

    Hennessy, Ricky; Markey, Mia K; Tunnell, James W

    2015-02-01

    Diffuse reflectance spectroscopy (DRS) can be used to noninvasively measure skin properties. To extract skin properties from DRS spectra, you need a model that relates the reflectance to the tissue properties. Most models are based on the assumption that skin is homogenous. In reality, skin is composed of multiple layers, and the homogeneity assumption can lead to errors. In this study, we analyze the errors caused by the homogeneity assumption. This is accomplished by creating realistic skin spectra using a computational model, then extracting properties from those spectra using a one-layer model. The extracted parameters are then compared to the parameters used to create the modeled spectra. We used a wavelength range of 400 to 750 nm and a source detector separation of 250 μm. Our results show that use of a one-layer skin model causes underestimation of hemoglobin concentration [Hb] and melanin concentration [mel]. Additionally, the magnitude of the error is dependent on epidermal thickness. The one-layer assumption also causes [Hb] and [mel] to be correlated. Oxygen saturation is overestimated when it is below 50% and underestimated when it is above 50%. We also found that the vessel radius factor used to account for pigment packaging is correlated with epidermal thickness.

  13. Impact of one-layer assumption on diffuse reflectance spectroscopy of skin

    NASA Astrophysics Data System (ADS)

    Hennessy, Ricky; Markey, Mia K.; Tunnell, James W.

    2015-02-01

    Diffuse reflectance spectroscopy (DRS) can be used to noninvasively measure skin properties. To extract skin properties from DRS spectra, you need a model that relates the reflectance to the tissue properties. Most models are based on the assumption that skin is homogenous. In reality, skin is composed of multiple layers, and the homogeneity assumption can lead to errors. In this study, we analyze the errors caused by the homogeneity assumption. This is accomplished by creating realistic skin spectra using a computational model, then extracting properties from those spectra using a one-layer model. The extracted parameters are then compared to the parameters used to create the modeled spectra. We used a wavelength range of 400 to 750 nm and a source detector separation of 250 μm. Our results show that use of a one-layer skin model causes underestimation of hemoglobin concentration [Hb] and melanin concentration [mel]. Additionally, the magnitude of the error is dependent on epidermal thickness. The one-layer assumption also causes [Hb] and [mel] to be correlated. Oxygen saturation is overestimated when it is below 50% and underestimated when it is above 50%. We also found that the vessel radius factor used to account for pigment packaging is correlated with epidermal thickness.

  14. Diffuse gamma-ray constraints on dark matter revisited I: the impact of subhalos

    SciTech Connect

    Blanchet, Steve; Lavalle, Julien E-mail: lavalle@in2p3.fr

    2012-11-01

    We make a detailed analysis of the indirect diffuse gamma-ray signals from dark matter annihilation in the Galaxy. We include the prompt emission, as well as the emission from inverse Compton scattering whenever the annihilation products contain light leptons. We consider both the contribution from the smooth dark matter halo and that from substructures. The main parameters for the latter are the mass function index and the minimal subhalo mass. We use recent results from N-body simulations to set the most reasonable range of parameters, and find that the signal can be boosted by a factor ranging from 2 to 15 towards the Galactic poles, slightly more towards the Galactic anticenter, with an important dependence on the subhalo mass index. This uncertainty is however much less than that of the extragalactic signal studied in the literature. We derive upper bounds on the dark matter annihilation cross section using the isotropic gamma-ray emission measured by Fermi-LAT, for two directions in the sky, the Galactic anticenter and the Galactic pole(s). The former represents the lowest irreducible signal from dark matter annihilation, and the latter is robust as the astrophysical background, dominated by the hadronic contribution, is rather well established in that direction. Finally, we show how the knowledge of the minimal subhalo mass, which formally depends on the dark matter particle interactions with normal matter, can be used to derive the mass function index.

  15. Derivation of particulate directional information from analysis of elliptical impact craters on LDEF

    NASA Technical Reports Server (NTRS)

    Newman, P. J.; Mackay, N.; Deshpande, S. P.; Green, S. F.; Mcdonnell, J. A. M.

    1993-01-01

    The Long Duration Exposure Facility provided a gravity gradient stabilized platform which allowed limited directional information to be derived from particle impact experiments. The morphology of impact craters on semi-infinite materials contains information which may be used to determine the direction of impact much more accurately. We demonstrate the applicability of this technique and present preliminary results of measurements from LDEF and modelling of interplanetary dust and space debris.

  16. Impacting Student Perceptions about Careers in Information Systems

    ERIC Educational Resources Information Center

    Walstrom, Kent A.; Schambach, Thomas P.

    2012-01-01

    A shortage of graduates prepared to fill the available jobs in Information Systems remains. Previous studies have verified the shortage and attempted to explain why students do not major in Information Technology related fields. Since prior studies identified lack of awareness regarding the discipline as a major reason in ignoring the major, the…

  17. The Impact of Information on Death Penalty Support, Revisited

    ERIC Educational Resources Information Center

    Lambert, Eric G.; Camp, Scott D.; Clarke, Alan; Jiang, Shanhe

    2011-01-01

    In 1972, former Supreme Court Justice Marshall postulated that the public was uninformed about the death penalty and information would change their support for it. There is some indication that information about the death penalty may change people's level of support. This study re-examines data used by Lambert and Clarke (2001). Using multivariate…

  18. Informational Technology and Its Impact on American Education.

    ERIC Educational Resources Information Center

    Congress of the U.S., Washington, DC. Office of Technology Assessment.

    This study, which examines the extent to which information technology could serve American needs for education and training, documents two basic sets of conclusions: (1) the so-called information revolution is profoundly affecting American education by changing the nature of what needs to be learned, who needs to learn it, who will provide it, and…

  19. Impacting Student Perceptions about Careers in Information Systems

    ERIC Educational Resources Information Center

    Walstrom, Kent A.; Schambach, Thomas P.

    2012-01-01

    A shortage of graduates prepared to fill the available jobs in Information Systems remains. Previous studies have verified the shortage and attempted to explain why students do not major in Information Technology related fields. Since prior studies identified lack of awareness regarding the discipline as a major reason in ignoring the major, the…

  20. The Impact of Social Media on Informal Learning in Museums

    ERIC Educational Resources Information Center

    Russo, Angelina; Watkins, Jerry; Groundwater-Smith, Susan

    2009-01-01

    This paper posits that social networking can take a central role in learning in informal environments such as museums, libraries and galleries. It argues that social media offers young people agency previously unavailable in informal learning environments in order to explore complex responses to and participation with cultural content. The paper…

  1. The Impact of Information on Death Penalty Support, Revisited

    ERIC Educational Resources Information Center

    Lambert, Eric G.; Camp, Scott D.; Clarke, Alan; Jiang, Shanhe

    2011-01-01

    In 1972, former Supreme Court Justice Marshall postulated that the public was uninformed about the death penalty and information would change their support for it. There is some indication that information about the death penalty may change people's level of support. This study re-examines data used by Lambert and Clarke (2001). Using multivariate…

  2. Privacy Impact Assessment for the Freedom of Information Act Online

    EPA Pesticide Factsheets

    This system collects the name and contact information for Freedom of Information Act requestors. Learn how the data will be collected in the system, how it will be used, access to the data, the purpose of data collection, and record retention policies.

  3. Societal Impact of Improved Environment and Geospatial Information

    NASA Astrophysics Data System (ADS)

    Pearlman, J.; Andrzejewska, M.; Stonor, T.

    2013-12-01

    Geospatial projects are often dogged by the inability to establish a strong quantitative value proposition and are unable to sustain the attention of senior decision makers. In a tough economic climate, it is particularly important that any project that requires a significant investment can show a clear Return on Investment (ROI). In the case of commerce, benefit can be quantified through increase in sales/profit or reduction of risk. In the case of societal impact, quantification is more challenging. At the Geospatial World Forum (GWF) 2013 in Rotterdam, a number of case studies were presented on social impacts which used differing approaches to impact assessment. Some of the cases discussed projects with community issues and explained alternative means of conflict resolution. However, a comparison of the different case studies was not made at the GWF meeting. This presentation will take the next step and address the commonalities and differences in the approaches.

  4. Additional information for impact response of the restart safety rods

    SciTech Connect

    Yau, W.W.F.

    1991-10-14

    WSRC-RP-91-677 studied the structural response of the safety rods under the conditions of brake failure and accidental release. It was concluded that the maximum impact loading to the safety rod is 6020 pounds based on conservative considerations that energy dissipation attributable to fluid resistance and reactor superstructure flexibility. The staffers of the Defense Nuclear Facility Safety Board reviewed the results and inquired about the extent of conservatism. By request of the RESTART team, I reassessed the impact force due to these conservative assumptions. This memorandum reports these assessments.

  5. Additional information for impact response of the restart safety rods

    SciTech Connect

    Yau, W.W.F.

    1991-10-14

    WSRC-RP-91-677 studied the structural response of the safety rods under the conditions of brake failure and accidental release. It was concluded that the maximum impact loading to the safety rod is 6020 pounds based on conservative considerations that energy dissipation attributable to fluid resistance and reactor superstructure flexibility. The staffers of the Defense Nuclear Facility Safety Board reviewed the results and inquired about the extent of conservatism. By request of the RESTART team, I reassessed the impact force due to these conservative assumptions. This memorandum reports these assessments.

  6. Evaluation of immunohistochemical subtypes in diffuse large B-cell lymphoma and its impact on survival.

    PubMed

    Dwivedi, Anamika; Mehta, Anurag; Solanki, Poonam

    2015-01-01

    Diffuse large B-cell lymphoma (DLBCL) is the most common type of non-Hodgkin lymphoma in Indian population. The disease could be divided into the prognostically important subtypes, germinal center B-cell (GCB)-like and activated B-cell-like, using gene expression profiling (GEP). The molecular subtype as defined by GEP could also be predicted by using immunohistochemistry (IHC) based algorithms using three biomarkers CD10, BCL-6, and multiple myeloma oncogene-1 (MUM1). It has been confirmed that patients belonging to the GCB subtype have a better outcome and survival than those belonging to the second subtype. The present study was conducted to study the prevalence of these two subgroups and their correlation with survival of the patients. A total of 83 patients of DLBCL were included in the study. Hematoxylin- and eosin-stained sections were prepared from the paraffin-embedded tissue blocks. The staining for all the three antibodies was considered positive when more than 30% cells were stained with the respective antibody. The results showed that 44 patients (53%) had GCB immunophenotype and 39 patients (47%) had non-GCB phenotype. However, no statistically significant difference in overall and disease-free survival was noted between the subgroups. This study demonstrated that frequency of GCB subtype of DLBCL is significantly higher than the non-GCB subtype, and the non-GCB immunophenotype has better relapse-free survival 78% (standard error = 0.10) at the end of 3 years, while GCB has 56% (standard error = 0.23). Further studies should be performed with larger number of patients to show difference in clinical outcome between GCB and non-GCB subgroups.

  7. Impacts from PCB accumulation on amphibians inhabiting streams flowing from the Paducah Gaseous Diffusion Plant.

    PubMed

    DeGarady, C J; Halbrook, R S

    2003-11-01

    Contamination at the Paducah Gaseous Diffusion Plant (PGDP), Paducah, Kentucky, has been under evaluation for many years. We studied amphibians in selected outfalls (drainage ditches) flowing from the PGDP to determine if PCBs were accumulating in their tissues and how this might affect local populations. We determined relative amphibian species richness and abundance among seven outfalls and three reference streams by listening to their calls during audio surveys. We also captured amphibians from each study site during the summers of 2000 and 2001 and analyzed their carcasses for PCBs (Aroclor 1260 and 34 congeners) and livers for ethoxyresorufin O-deethylase (EROD) activity, a biomarker of PCBs and other organic contamination. Ten species were heard across study sites, and abundance and richness at outfalls were similar to those observed at reference sites. However, there were significant differences in abundance (p = 0.001) and richness (p = 0.048) of amphibians between continuously flowing and intermittent outfalls. There were no significant differences in PCB concentrations (p = 0.113) in amphibians captured from study sites, although Aroclor 1260 concentrations tended to be higher in amphibians collected from one outfall (outfall 12) on the east side of the plant (x = 1260 microg/kg) compared with all other study sites (x = 489 microg/kg). EROD activity measured in the liver was not indicative of Aroclor 1260 concentrations in amphibians at the PGDP, and EROD did not differ by study site, species, age class, or gender. PCB concentrations measured in amphibians at the PGDP were similar to concentrations measured at reference sites and did not appear to negatively affect individual amphibians or abundance and richness.

  8. Impact of Selection and Demography on the Diffusion of Lactase Persistence

    PubMed Central

    Currat, Mathias; Sanchez-Mazas, Alicia

    2009-01-01

    Background The lactase enzyme allows lactose digestion in fresh milk. Its activity strongly decreases after the weaning phase in most humans, but persists at a high frequency in Europe and some nomadic populations. Two hypotheses are usually proposed to explain the particular distribution of the lactase persistence phenotype. The gene-culture coevolution hypothesis supposes a nutritional advantage of lactose digestion in pastoral populations. The calcium assimilation hypothesis suggests that carriers of the lactase persistence allele(s) (LCT*P) are favoured in high-latitude regions, where sunshine is insufficient to allow accurate vitamin-D synthesis. In this work, we test the validity of these two hypotheses on a large worldwide dataset of lactase persistence frequencies by using several complementary approaches. Methodology We first analyse the distribution of lactase persistence in various continents in relation to geographic variation, pastoralism levels, and the genetic patterns observed for other independent polymorphisms. Then we use computer simulations and a large database of archaeological dates for the introduction of domestication to explore the evolution of these frequencies in Europe according to different demographic scenarios and selection intensities. Conclusions Our results show that gene-culture coevolution is a likely hypothesis in Africa as high LCT*P frequencies are preferentially found in pastoral populations. In Europe, we show that population history played an important role in the diffusion of lactase persistence over the continent. Moreover, selection pressure on lactase persistence has been very high in the North-western part of the continent, by contrast to the South-eastern part where genetic drift alone can explain the observed frequencies. This selection pressure increasing with latitude is highly compatible with the calcium assimilation hypothesis while the gene-culture coevolution hypothesis cannot be ruled out if a positively

  9. Impact of selection and demography on the diffusion of lactase persistence.

    PubMed

    Gerbault, Pascale; Moret, Céline; Currat, Mathias; Sanchez-Mazas, Alicia

    2009-07-24

    The lactase enzyme allows lactose digestion in fresh milk. Its activity strongly decreases after the weaning phase in most humans, but persists at a high frequency in Europe and some nomadic populations. Two hypotheses are usually proposed to explain the particular distribution of the lactase persistence phenotype. The gene-culture coevolution hypothesis supposes a nutritional advantage of lactose digestion in pastoral populations. The calcium assimilation hypothesis suggests that carriers of the lactase persistence allele(s) (LCT*P) are favoured in high-latitude regions, where sunshine is insufficient to allow accurate vitamin-D synthesis. In this work, we test the validity of these two hypotheses on a large worldwide dataset of lactase persistence frequencies by using several complementary approaches. We first analyse the distribution of lactase persistence in various continents in relation to geographic variation, pastoralism levels, and the genetic patterns observed for other independent polymorphisms. Then we use computer simulations and a large database of archaeological dates for the introduction of domestication to explore the evolution of these frequencies in Europe according to different demographic scenarios and selection intensities. Our results show that gene-culture coevolution is a likely hypothesis in Africa as high LCT*P frequencies are preferentially found in pastoral populations. In Europe, we show that population history played an important role in the diffusion of lactase persistence over the continent. Moreover, selection pressure on lactase persistence has been very high in the North-western part of the continent, by contrast to the South-eastern part where genetic drift alone can explain the observed frequencies. This selection pressure increasing with latitude is highly compatible with the calcium assimilation hypothesis while the gene-culture coevolution hypothesis cannot be ruled out if a positively selected lactase gene was carried at

  10. Diffusion Magnetic Resonance Imaging and Fiber Tractography: The State of the Art and its Potential Impact on Patient Management.

    PubMed

    Vos, Sjoerd B; Tax, Chantal M W; Leemans, Alexander

    2013-07-01

    Diffusion magnetic resonance (MR) imaging is sensitive to microstructural changes in tissue. Diffusion tensor MR imaging, the most commonly used method, can estimate the magnitude and anisotropy of diffusion. These tensor-based diffusion parameters have been shown to change in many neuropathologic conditions. Recent advances in diffusion MR imaging techniques may provide quantitative measures that are more specific to the underlying tissue change. Diffusion MR imaging data can also be used to provide fiber tractography. In this article, an overview of the basic principles of these techniques is provided, and their current and potential uses in clinical research and clinical practice are discussed. Copyright © 2013 Elsevier Inc. All rights reserved.

  11. The impact of health information technology on staffing.

    PubMed

    Goldsack, Jennifer C; Robinson, Edmondo J

    2014-02-01

    Hospitals nationwide must demonstrate meaningful use by 2015 or face fines. For over 20 years, researchers have attempted to assess the impact of electronic record keeping technologies on the quality, safety, and efficiency of care, but results are inconclusive and hospital managers have little evidence on which to base staffing decisions as we hurtle toward the era of the paperless hospital.

  12. Federal Environmental Impact Statements as an Important Source of Information.

    ERIC Educational Resources Information Center

    Orr, Patricia S.

    1995-01-01

    Examines the background and characteristics of environmental impact statements (EIS), and discusses the sources that provide bibliographic control for EISs. Explores the usefulness of EISs, outlines their legislative basis, describes the EIS process and format, and identifies sources that facilitate access to them. (Author/DGM)

  13. Replacement of chlorofluorocarbons (CFCs) at the DOE Gaseous Diffusion Plants: An assessment of global impacts

    SciTech Connect

    Socolof, M.L.; Saylor, R.E.; McCold, L.N.

    1994-12-31

    The US Department of Energy (DOE) operates two uranium enrichment plants. Together, the two plants maintain an inventory of approximately 14 million pounds of a chlorofluorocarbon (CFC), dichlorote-trafluoroethane (CFC-114) as a coolant. Annual operational CFC-114 losses total over 500,000 pounds. In February, 1992, President Bush announced that the US would terminate manufacture and importation of Class 1 ozone depleting substances (including CFC-114) by the end of 1995. To comply with this requirement DOE has considered introducing a replacement coolant by the end of 1995. Two perfluorocarbons (PFCs) - namely, octofluoro-cyclobutane and decafluorobutane - are presently the only known coolants that could meet safety requirements. They would not contribute to stratospheric ozone depletion but contribute to global warming. The paper describes an analysis of the potential global impacts of the proposed replacement of CFC-114 with a PFC. A problem with analyses of global warming and ozone depletion impacts is that even large sources of compounds that contribute to these effects contribute only very small fractions of the total effect. The authors take the position that significant effects to global warming and ozone depletion have already occurred, and that any additional contribution to these effects are contributions to cumulatively significant adverse effects on the environment. The paper describes four alternatives and the extent to which each would contribute to global warming and ozone depletion.

  14. Impacts of the climate change on runoff and diffuse phosphorus load to Lake Balaton (Hungary).

    PubMed

    Kovács, A; Clement, A

    2009-01-01

    The paper outlines a multi-component assessment of the impacts of the climate change on runoff and total phosphorus loads to the large shallow Lake Balaton in Hungary. Present hydrological cycle of the lake catchment has been examined using the rainfall-runoff model WetSpa. Particular phosphorus concentration in runoff was estimated on the basis of the simulated streamflow using an empirical power equation. Dissolved phosphorus concentrations were determined as a function of landuse and soil type of the corresponding sub-catchment. The model was calibrated and validated against daily observations manually at monitoring sites of sixteen inflowing streams around the lake. Runoff stemming from shoreline urban developments was calculated by the urban runoff simulation model SWMM. Phosphorus concentrations in urban runoff were calculated by an empirical relationship derived from field measurements. The model was henceforward run for climate change scenario analysis. Present weather data were modified by the climate change scenarios imported from the results of the CLIME project. The results indicate that the impact of the climate change on runoff and phosphorus load appears in the change of the distribution within a time period rather than in the total volume. However, due to the high uncertainties in climate models, the presented calculations are possible assumptions rather than established statements.

  15. Assessing the socioeconomic impact and value of open geospatial information

    USGS Publications Warehouse

    Pearlman, Francoise; Pearlman, Jay; Bernknopf, Richard; Coote, Andrew; Craglia, Massimo; Friedl, Lawrence; Gallo, Jason; Hertzfeld, Henry; Jolly, Claire; Macauley, Molly; Shapiro, Carl; Smart, Alan

    2016-03-10

    The workshop included 68 participants coming from international organizations, the U.S. public and private sectors, nongovernmental organizations, and academia. Participants included policy makers and analysts, financial analysts, economists, information scientists, geospatial practitioners, and other discipline experts.

  16. Privacy Impact Assessment for the Peer Reviewer Panelist Information System

    EPA Pesticide Factsheets

    This system collects contact and employment information. Learn how this data will be collected in the system, how it will be used, access to the data, the purpose of data collection, and record retention policies for this data.

  17. Designing-and Redesigning-Information Services for Maximum Impact.

    ERIC Educational Resources Information Center

    Jones, Rebecca; Dysart, Jane

    2002-01-01

    Discusses innovative information services, including new services and the redesign of existing services. Describes the development process, including assessing the market and developing a marketing plan; and explains the implementation process, including monitoring client satisfaction and quality control. (LRW)

  18. Designing-and Redesigning-Information Services for Maximum Impact.

    ERIC Educational Resources Information Center

    Jones, Rebecca; Dysart, Jane

    2002-01-01

    Discusses innovative information services, including new services and the redesign of existing services. Describes the development process, including assessing the market and developing a marketing plan; and explains the implementation process, including monitoring client satisfaction and quality control. (LRW)

  19. Feature saliency and feedback information interactively impact visual category learning

    PubMed Central

    Hammer, Rubi; Sloutsky, Vladimir; Grill-Spector, Kalanit

    2015-01-01

    Visual category learning (VCL) involves detecting which features are most relevant for categorization. VCL relies on attentional learning, which enables effectively redirecting attention to object’s features most relevant for categorization, while ‘filtering out’ irrelevant features. When features relevant for categorization are not salient, VCL relies also on perceptual learning, which enables becoming more sensitive to subtle yet important differences between objects. Little is known about how attentional learning and perceptual learning interact when VCL relies on both processes at the same time. Here we tested this interaction. Participants performed VCL tasks in which they learned to categorize novel stimuli by detecting the feature dimension relevant for categorization. Tasks varied both in feature saliency (low-saliency tasks that required perceptual learning vs. high-saliency tasks), and in feedback information (tasks with mid-information, moderately ambiguous feedback that increased attentional load, vs. tasks with high-information non-ambiguous feedback). We found that mid-information and high-information feedback were similarly effective for VCL in high-saliency tasks. This suggests that an increased attentional load, associated with the processing of moderately ambiguous feedback, has little effect on VCL when features are salient. In low-saliency tasks, VCL relied on slower perceptual learning; but when the feedback was highly informative participants were able to ultimately attain the same performance as during the high-saliency VCL tasks. However, VCL was significantly compromised in the low-saliency mid-information feedback task. We suggest that such low-saliency mid-information learning scenarios are characterized by a ‘cognitive loop paradox’ where two interdependent learning processes have to take place simultaneously. PMID:25745404

  20. Pre-Service Teachers' Perspectives of the Diffusion of Information and Communications Technologies (ICTs) and the Effect of Case-Based Discussions (CBDs)

    ERIC Educational Resources Information Center

    Sahin, Sami

    2012-01-01

    This study investigates pre-service teachers' perspectives of the diffusion of information and communication technologies (ICTs) in elementary education and the effect of case-based discussions (CBDs). The sample consisted of 170 first-year pre-service teachers from elementary teacher education programs of the largest teacher education college in…

  1. Pre-Service Teachers' Perspectives of the Diffusion of Information and Communications Technologies (ICTs) and the Effect of Case-Based Discussions (CBDs)

    ERIC Educational Resources Information Center

    Sahin, Sami

    2012-01-01

    This study investigates pre-service teachers' perspectives of the diffusion of information and communication technologies (ICTs) in elementary education and the effect of case-based discussions (CBDs). The sample consisted of 170 first-year pre-service teachers from elementary teacher education programs of the largest teacher education college in…

  2. Assessment of climate change impacts on diffuse nutrient and pesticide fluxes at the watershed scale

    NASA Astrophysics Data System (ADS)

    Arabi, M.; Records, R.; Ahmadi, M.

    2012-12-01

    The study aims to assess the potential impacts of the changing climate on pollutant fluxes including sediment, phosphorus, nitrogen, and atrazine at the watershed scale over the 21st century. Specific objectives are (i) to understand changes in climatic conditions under a comprehensive set of 112 climate projections consistent with Intergovernmental Panel on Climate Change Special Report on Emissions Scenarios (IPCC-SRES) emission pathways and models; (ii) to fully enumerate and synthesize hydrologic and water quality responses to projected climate scenarios; and (iii) to investigate changes in dissolved and particulate water quality constituents. These objectives were investigated in a predominantly agricultural watershed in the Midwestern United States. The hydrologic model Soil and Water Assessment Tool (SWAT) was utilized to represent processes governing hydrology and water quality within the watershed. The SWAT model was driven with a suite of 112 distinct dynamically downscaled climate projections representing IPCC-SERES low, moderate, and high greenhouse gas emission pathways. Statistical downscaling procedures were used to derive daily climatic values for meteorological stations in the study area from grid-based dynamically downscaled monthly predictions. Predicted changes in hydroclimatic, nutrient, and pesticide fluxes under the 112 distinct simulations were then analyzed by emission pathway ensemble and characterized over early-, mid-, and late-century assessment periods (2015-2034, 2045-2064, and 2080-2099). Clear warming trends were apparent for temperature, while increases in precipitation were insignificant. Stream discharge, sediment yield, and total nutrient yields did not differ significantly between assessment periods, although atrazine yields were predicted to be slightly greater by late-century. However, the proportion of dissolved to total nutrients increased, with nitrate and soluble phosphorus yields increasing significantly between early

  3. Investigating the impact of advective and diffusive controls in solute transport on geoelectrical data

    NASA Astrophysics Data System (ADS)

    Wheaton, Daniel D.; Singha, Kamini

    2010-09-01

    Multiple types of physical heterogeneity have been suggested to explain anomalous solute transport behavior, yet determining exactly what controls transport at a given site is difficult from concentration histories alone. Differences in timing between co-located fluid and bulk apparent electrical conductivity data have previously been used to estimate solute mass transfer rates between mobile and less-mobile domains; here, we consider if this behavior can arise from other types of heterogeneity. Numerical models are used to investigate the electrical signatures associated with large-scale hydraulic conductivity heterogeneity and small-scale dual-domain mass transfer, and address issues regarding the scale of the geophysical measurement. We examine the transport behavior of solutes with and without dual-domain mass transfer, in: 1) a homogeneous medium, 2) a discretely fractured medium, and 3) a hydraulic conductivity field generated with sequential Gaussian simulation. We use the finite-element code COMSOL Multiphysics to construct two-dimensional cross-sectional models and solve the coupled flow, transport, and electrical conduction equations. Our results show that both large-scale heterogeneity and subscale heterogeneity described by dual-domain mass transfer produce a measurable hysteresis between fluid and bulk apparent electrical conductivity, indicating a lag between electrical conductivity changes in the mobile and less-mobile domains of an aquifer, or mass transfer processes, at some scale. The shape and magnitude of the observed hysteresis is controlled by the spatial distribution of hydraulic heterogeneity, mass transfer rate between domains, and the ratio of mobile to immobile porosity. Because the rate of mass transfer is related to the inverse square of a diffusion length scale, our results suggest that the shape of the hysteresis curve is indicative of the length scale over which mass transfer is occurring. We also demonstrate that the difference in

  4. Impact of nonintentional Al impurity to carrier lifetime and diffusion in sublimation grown 3C heterostructures

    NASA Astrophysics Data System (ADS)

    Ščajev, P.; Jarašiunas, K.; Kadys, A.; Storasta, J.; Abramov, P. L.; Lebedev, S. P.; Lebedev, A. A.

    2010-11-01

    Using optical techniques, we analyzed an impact of non-intentional Al mpurity and twin boundaries to photoelectrical properties of sublimation-grown 3C heterostructures. Differential transmission techniques revealed Al related contribution to probe beam absorption with cross-section σAl = (1.8±0.5)×10-17 cm2 at 1064 nm, being four times stronger that the free-carrier absorption cross-section at given wavelength. Temperature dependent carrier recombination rates provided trap activation energy of 170 and 210 meV in two samples with different Al concentration. Saturation of probe beam absorption with excitation allowed determination of electrically active Al concentration, not gettered at grain boundaries. Increase of room-temperature mobility with injection in the highly defective layer and the corresponding lifetime decrease pointed out contribution of point and structural defects to carrier scattering.

  5. Mechanisms of Innovation Diffusion under Information Abundance and Information Scarcity--On the Contribution of Social Networks in Group vs. Individual Extension Approaches in Semi-Arid Kenya

    ERIC Educational Resources Information Center

    Darr, Dietrich; Pretzsch, Jurgen

    2008-01-01

    Purpose: The objective of this paper is to assess the effectiveness of innovation diffusion under group-oriented and individual-oriented extension. Current theoretical notions of innovation diffusion in social networks shall be briefly reviewed, and the concepts of "search" and "innovation" vis-a-vis "transfer" and…

  6. 77 FR 46748 - Notice of Proposed Information Collection Requests; Institute of Education Sciences; Impact...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-08-06

    ... Notice of Proposed Information Collection Requests; Institute of Education Sciences; Impact Evaluation of... information on the kinds of performance evaluation systems currently discussed in federal policy. DATES...-4537. Copies of the proposed information collection request may be accessed from http://edicsweb.ed.gov...

  7. Impact of Informal Science Education on Children's Attitudes About Science

    NASA Astrophysics Data System (ADS)

    Wulf, Rosemary; Mayhew, Laurel M.; Finkelstein, Noah D.

    2010-10-01

    The JILA Physics Frontier Center Partnerships for Informal Science Education in the Community (PISEC) provides informal afterschool inquiry-based science teaching opportunities for university participants with children typically underrepresented in science. We focus on the potential for this program to help increase children's interest in science, mathematics, and engineering and their understanding of the nature of science by validating the Children's Attitude Survey, which is based on the Colorado Learning Attitudes about Science Survey [1] and designed to measure shifts in children's attitudes about science and the nature of science. We present pre- and post-semester results for several semesters of the PISEC program, and demonstrate that, unlike most introductory physics courses in college, our after-school informal science programs support and promote positive attitudes about science.

  8. The Development and Impact of a Global Information System.

    ERIC Educational Resources Information Center

    Kranch, Douglas A.

    1989-01-01

    Predicts that, over the next several decades, technological advancements in large scale database construction and maintenance, high speed digital transmission networks, and highly precise intelligent searchware will result in a worldwide information system. A projected model illustrates pricing and retrieval rate changes that may be expected over…

  9. The Impact of New Information Technology on Bureaucratic Organizational Culture

    ERIC Educational Resources Information Center

    Givens, Mark A.

    2011-01-01

    Virtual work environments (VWEs) have been used in the private sector for more than a decade, but the United States Marine Corps (USMC), as a whole, has not yet taken advantage of associated benefits. The USMC construct parallels the bureaucratic organizational culture and uses an antiquated information technology (IT) infrastructure. During an…

  10. The Information Machines; Their Impact on Men and the Media.

    ERIC Educational Resources Information Center

    Bagdikian, Ben H.

    "Today we are on the threshold of a change in human communications which is more powerful and perhaps more significant than all past changes in the technology of information. The way men deal with each other and with the distant world is about to be transformed by a combination of the computer, innovations in the transmission of signals, and new…

  11. Information Assurance Alignment: A Study of Performance Impacts

    ERIC Educational Resources Information Center

    Ghezal, Said

    2011-01-01

    The positive effect on performance of the alignment between a business strategy and its different functional strategies has a wide support in the literature. As an emerging functional area, information assurance has come to play a strategic role by providing all departments and functions across an organization with a reliable, safe, and efficient…

  12. Impact of Information Technology Governance Structures on Strategic Alignment

    ERIC Educational Resources Information Center

    Gordon, Fitzroy R.

    2013-01-01

    This dissertation is a study of the relationship between Information Technology (IT) strategic alignment and IT governance structure within the organization. This dissertation replicates Asante (2010) among a different population where the prior results continue to hold, the non-experimental approach explored two research questions but include two…

  13. Impact of Anaphoric Resolution in Information Retrieval. Final Report.

    ERIC Educational Resources Information Center

    Katzer, Jeffrey; And Others

    This project examines anaphora (the linguistic device of abbreviated subsequent reference to a concept) in information retrieval (IR) systems in order to develop procedures to recognize anaphors in text and distinguish between anaphoric and non-anaphoric uses of a given term, estimate the number of anaphors appearing in bibliographic records, and…

  14. Course Syllabus: The Social Impact of Computer Information Technology.

    ERIC Educational Resources Information Center

    Behar, Joseph

    1988-01-01

    This syllabus describes the course background, central themes and issues, texts, resources, and recommended readings. Main topics are the sociology of information technology, computers and social change, telecommunications, computers and human interactions, applications in working, and social issues and political implications. (YP)

  15. Demoralisation: its impact on informed consent and medical care.

    PubMed

    Kissane, D W

    2001-11-19

    Demoralisation, a mental state characterised by hopelessness and meaninglessness, can be differentiated from depression in that demoralised patients can enjoy the present, their lack of hope being confined to the future. However, like severe depression, demoralisation can interfere with a person's capacity to give informed consent. Doctors and other health professionals are also subject to demoralisation, which influences medical care.

  16. The Development and Impact of a Global Information System.

    ERIC Educational Resources Information Center

    Kranch, Douglas A.

    1989-01-01

    Predicts that, over the next several decades, technological advancements in large scale database construction and maintenance, high speed digital transmission networks, and highly precise intelligent searchware will result in a worldwide information system. A projected model illustrates pricing and retrieval rate changes that may be expected over…

  17. Impact of information compression on intellectual activities in the brain.

    PubMed

    Eriksson, J T

    1996-09-01

    Imaging and modeling represent an action of information compression, which is inevitable for a complex system in order to process and communicate data. Humans are such complex systems. Sensational and body reaction information is processed by the brain, the overall information rate being 10(11)-10(12) bit/s. Consciousness is the result of massive information compression, the attentional data rate being 10-14 bit/s. The primary purpose of the conscious state is to control the interaction with the environment. In humans, this ability facilitates the projection of the future horizon far away from the next instant. Thinking and reasoning can be thought of as a process of retrospective control. Retrospective in the sense that the sub-conscious has already decided what is to come next. In the long run, however, conscious thought influences the cortical context potentiation, thus providing steering to the associative process. The paper emphasizes that all cognitive operations are restricted to the bioelectrical signal processing of the brain. Accordingly, mental models and scientific theories will always be constrained by this fact. The last subject of this paper deals with the interaction between the brain, the glands and the rest of the body. It is interpreted that qualia are the result of a complex feedback interaction between those parts, a self-supported process close to a singularity point.

  18. Interchange 63: The Impact of Information and Communications Technology Initiatives.

    ERIC Educational Resources Information Center

    Scottish Executive Education Dept., Edinburgh.

    This document reports the results of a study that assessed the effects of Information and Communications Technology (ICT) on students' skills and knowledge. The study analyzes the effect of using ICT on students' skills, motivation, and attitudes, and describes teachers' experiences with and views on the potential of ICT. (YDS)

  19. The Impact of Information Technology on the Individual.

    ERIC Educational Resources Information Center

    Palmquist, Ruth A.

    1992-01-01

    Discusses technological change and reviews recent research on or forecasts about how computer-based technologies affect the environments in which the individual functions. Topics addressed include the individual's need for social experience; influences on the individual's work life; and citizenship, including control over information and…

  20. Impact of Information Technology Governance Structures on Strategic Alignment

    ERIC Educational Resources Information Center

    Gordon, Fitzroy R.

    2013-01-01

    This dissertation is a study of the relationship between Information Technology (IT) strategic alignment and IT governance structure within the organization. This dissertation replicates Asante (2010) among a different population where the prior results continue to hold, the non-experimental approach explored two research questions but include two…

  1. The Impact of New Information Technology on Bureaucratic Organizational Culture

    ERIC Educational Resources Information Center

    Givens, Mark A.

    2011-01-01

    Virtual work environments (VWEs) have been used in the private sector for more than a decade, but the United States Marine Corps (USMC), as a whole, has not yet taken advantage of associated benefits. The USMC construct parallels the bureaucratic organizational culture and uses an antiquated information technology (IT) infrastructure. During an…

  2. Impact of diffuse nitrate pollution sources on groundwater quality--some examples from Czechoslovakia.

    PubMed Central

    Benes, V; Pĕkný, V; Skorepa, J; Vrba, J

    1989-01-01

    In several regions of Czechoslovakia with intensive agricultural production, the correlation between the amount of nitrogen fertilizer applied and the nitrate content in groundwater has been recognized. Nitrate pollution of groundwater is considered to be the most serious source of nonpoint pollution in Czechoslovakia. A program of research into the effects of farming activities on groundwater quality in Czechoslovakia is under way on experimental fields (20 to 30 hectares) and, simultaneously, in regions in which shallow, vulnerable aquifers occur. The importance of the soil organic matter's stability for maintaining the groundwater quality is emphasized. Research based on nitrogen and organic carbon balance has shown that the restoration of a soil-groundwater system is a complicated process that usually requires changes in the extent and intensity of agricultural activities and consistent attention to the effects produced by natural conditions. Regional investigation of the impact of farming on shallow aquifers in the fluvial deposits of the Elbe River in Bohemia has proved the hydrochemical instability and vertical hydrochemical heterogeneity of these aquifers. The WASTEN deterministic model was used for modeling the transport and transformation of various types of inorganic fertilizers. The input data is based on laboratory and field measurements. Special topics are the verification of model calculations and the time and spatial variability of input data with respect to the unsaturated zone. The research results are being used for making regional and national agro-groundwater managerial schemes more precise, as well as for decision-making. PMID:2559844

  3. Impact of preanesthetic information on anxiety of parents and children.

    PubMed

    Cumino, Débora de Oliveira; Cagno, Guilherme; Gonçalves, Vinícius Francisco Zacarias; Wajman, Denis Schapira; Mathias, Lígia Andrade da Silva Telles

    2013-01-01

    Preoperative Anxiety is a negative factor in anesthetic and surgical experience. Among the strategies for reducing children's anxiety, non-pharmacological strategies are as important as the pharmacological ones, but its validity is still controversial. The aim of this study was to verify if the information provided to guardians interferes with child anxiety. 72 children, 4-8 years old, ASA I and II, undergoing elective surgical procedures and their guardians were randomly divided into two groups: control group (CG) = guardian received conventional information about anesthesia; informative group (IG) = guardian received an information leaflet about anesthesia. Children's anxiety was assessed using the modified Yale Preoperative Anxiety Scale (m-YPAS) on two occasions: at the surgical theater waiting room (WR) and at the operating room (OR). Parents' anxiety was assessed using the Hamilton Anxiety Scale (HAM-A) at the CT. There was no difference in demographic data between groups. The level of anxiety in children showed no difference between groups at two measured times. There was statistically significant difference in anxiety levels between WR and OR in both groups, p = 0.0019 for CG and p < 0.0001 for GI, as well as the prevalence of anxiety for CG (38.9% WR and 69.4% OR, p = 0.0174) and GI (19.4% WR and 83.3% OR, p < 0.0001). The anxiety level of guardians did not differ between groups. Regardless of the quality of information provided to the guardians, the level and prevalence of anxiety in children were low at WR time and significantly increased at OR time. Copyright © 2013 Sociedade Brasileira de Anestesiologia. Published by Elsevier Editora Ltda. All rights reserved.

  4. Indian aspects of drug information resources and impact of drug information centre on community

    PubMed Central

    Chauhan, Nitesh; Moin, Sabeeya; Pandey, Anushree; Mittal, Ashu; Bajaj, Umakant

    2013-01-01

    Drug information centre refer to facility specially set aside for, and specializing in the provision of drug information and related issues. The purpose of drug information center is to provide authentic individualized, accurate, relevant and unbiased drug information to the consumers and healthcare professionals regarding medication related inquiries to the nation for health care and drug safety aspects by answering their call regarding the all critical problems on drug information, their uses and their side effects. Apart from that the center also provides in-depth, impartial source of crucial drug information to meet the needs of the practicing physicians, pharmacists and other health care professionals to safeguard the health, financial and legal interests of the patient and to broaden the pharmacist role visible in the society and community. The service should include collecting, reviewing, evaluating, indexing and distributing information on drugs to health workers. Drug and poisons information centers are best established within major teaching hospitals. This allows access to clinical experience, libraries, research facilities and educational activities. Information present in the current paper will not only enlighten the role of drug information center but also focused on the rational use of drug. PMID:23833748

  5. Indian aspects of drug information resources and impact of drug information centre on community.

    PubMed

    Chauhan, Nitesh; Moin, Sabeeya; Pandey, Anushree; Mittal, Ashu; Bajaj, Umakant

    2013-04-01

    Drug information centre refer to facility specially set aside for, and specializing in the provision of drug information and related issues. The purpose of drug information center is to provide authentic individualized, accurate, relevant and unbiased drug information to the consumers and healthcare professionals regarding medication related inquiries to the nation for health care and drug safety aspects by answering their call regarding the all critical problems on drug information, their uses and their side effects. Apart from that the center also provides in-depth, impartial source of crucial drug information to meet the needs of the practicing physicians, pharmacists and other health care professionals to safeguard the health, financial and legal interests of the patient and to broaden the pharmacist role visible in the society and community. The service should include collecting, reviewing, evaluating, indexing and distributing information on drugs to health workers. Drug and poisons information centers are best established within major teaching hospitals. This allows access to clinical experience, libraries, research facilities and educational activities. Information present in the current paper will not only enlighten the role of drug information center but also focused on the rational use of drug.

  6. Information and the War against Terrorism, Part III: New Information-Related Laws and the Impact on Civil Liberties.

    ERIC Educational Resources Information Center

    Strickland, Lee S.

    2002-01-01

    Reviews provisions of information-related laws in light of the September 11th attacks and their impact on civil liberties. Highlights include the USA Patriot Act of 2001; law enforcement and the ECPA (Electronic Communications Privacy Act); intelligence and the FISA (Foreign Intelligence Surveillance Act of 1978); implications for information…

  7. Information and the War against Terrorism, Part III: New Information-Related Laws and the Impact on Civil Liberties.

    ERIC Educational Resources Information Center

    Strickland, Lee S.

    2002-01-01

    Reviews provisions of information-related laws in light of the September 11th attacks and their impact on civil liberties. Highlights include the USA Patriot Act of 2001; law enforcement and the ECPA (Electronic Communications Privacy Act); intelligence and the FISA (Foreign Intelligence Surveillance Act of 1978); implications for information…

  8. Geobase Information System Impacts on Space Image Formats

    NASA Technical Reports Server (NTRS)

    Simonett, D. S. (Editor); Smith, T. R. (Editor); Tobler, W. (Editor); Marks, D. G. (Editor); Frew, J. E. (Editor); Dozier, J. C. (Editor)

    1978-01-01

    As Geobase Information Systems increase in number, size and complexity, the format compatability of satellite remote sensing data becomes increasingly more important. Because of the vast and continually increasing quantity of data available from remote sensing systems the utility of these data is increasingly dependent on the degree to which their formats facilitate, or hinder, their incorporation into Geobase Information Systems. To merge satellite data into a geobase system requires that they both have a compatible geographic referencing system. Greater acceptance of satellite data by the user community will be facilitated if the data are in a form which most readily corresponds to existing geobase data structures. The conference addressed a number of specific topics and made recommendations.

  9. Information system for monitoring environmental impacts of genetically modified organisms.

    PubMed

    Reuter, Hauke; Middelhoff, Ulrike; Graef, Frieder; Verhoeven, Richard; Batz, Thomas; Weis, Martin; Schmidt, Gunther; Schröder, Winfried; Breckling, Broder

    2010-09-01

    European legislation stipulates that genetically modified organisms (GMO) have to be monitored to identify potential adverse environmental effects. A wealth of different types of monitoring data from various sources including existing environmental monitoring programmes is expected to accumulate. This requires an information system to efficiently structure, process and evaluate the monitoring data. A structure for an Information System for Monitoring GMO (ISMO) was developed by a multidisciplinary research team. It is based on the requirement to organise all relevant information in a logical, readily accessible and functional manner. For the ISMO, we present a combination of three interrelated components: Firstly, an ISMO should comprise a knowledge database structured according to information related to the different scale levels of biological organisation relevant to GMO monitoring and scientific hypotheses on cause-effects which should be validated by monitoring data. Secondly, a monitoring database should be part of an ISMO containing GMO-specific monitoring data and meta-data. This monitoring database should be linked with monitoring data from other monitoring programmes which are relevant for GMO-related questions. Thirdly, an ISMO should encompass a database covering administrative and procedural data. Neither national nor international approaches to an ISMO exist yet. An ISMO as designed in this paper could support competent authorities in both the GMO notification process and in post-market monitoring. This includes evaluating the environmental risks of experimentally releasing GMO and placing them on the market, assessing monitoring plans and evaluating monitoring results. The ISMO should be implemented on both the national and international level, preferably combining different administrative scales. Harmonisation approaches towards GMO monitoring data are at an initial stage, but they are a precondition to coordinated GMO monitoring and to successfully

  10. Science informing decisions: the Pacific Northwest Climate Impacts Group

    NASA Astrophysics Data System (ADS)

    Miles, E. L.; Mote, P. W.; Whitely Binder, L.

    2008-12-01

    Since its founding in 1995, the Climate Impacts Group (CIG) at the University of Washington (UW) has achieved remarkable success at translating global- and regional-scale science into forms and products that are useful to, and used by, decision-makers. From GCM scenarios to research on the connection between global climate patterns and locally important factors like floods and wildfires, CIG's strong physical science foundation is matched by a vigorous and successful outreach program. As a result, CIG and its partner the Office of Washington State Climatologist at UW are deeply involved in advising all levels of government and many business interests on adapting to climate variability and change. This talk will showcase some of the specific activities and tools and illustrate how such efforts fit into a "National Climate Service."

  11. Impact of information and communications technologies on residental customer energy services

    SciTech Connect

    Goldman, C.; Kempton, W.; Eide, A.; Iyer, M.

    1996-10-01

    This study analyzes the potential impact of information and communications technologies on utility delivery of residential customer energy services. Many utilities are conducting trials which test energy-related and non-energy services using advanced communications systems.

  12. 78 FR 2379 - Agency Information Collection Activities; Comment Request; Impact Evaluation of Math Professional...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-01-11

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF EDUCATION Agency Information Collection Activities; Comment Request; Impact Evaluation of Math Professional Development AGENCY: IES/NCES, Department of Education (ED). ACTION: Notice. SUMMARY: In accordance with...

  13. The Information Technology Age and Its Impact on Business and Business Education Curriculums.

    ERIC Educational Resources Information Center

    Frueling, Rosemary T.; Kerin, John D.; Sebastian, David

    1997-01-01

    Examines the impact of continued growth of information technologies on the business environment and business education. Outlines the knowledge worker's need for applied communication, math, technology, and basic business skills. (SK)

  14. Hanford site solid waste management environmental impact statement technical information document [SEC 1 THRU 4

    SciTech Connect

    FRITZ, L.L.

    2003-04-01

    This Technical Information Document (TID) provides engineering data to support DOE/EIS-0286, ''Hanford Site Solid (Radioactive and Hazardous) Waste Program Environmental Impact Statement,'' including assumptions and waste volumes calculation data.

  15. The Impact of Information Richness on Information Security Awareness Training Effectiveness

    ERIC Educational Resources Information Center

    Shaw, R. S.; Chen, Charlie C.; Harris, Albert L.; Huang, Hui-Jou

    2009-01-01

    In recent years, rapid progress in the use of the internet has resulted in huge losses in many organizations due to lax security. As a result, information security awareness is becoming an important issue to anyone using the Internet. To reduce losses, organizations have made information security awareness a top priority. The three main barriers…

  16. The Impact of Information Richness on Information Security Awareness Training Effectiveness

    ERIC Educational Resources Information Center

    Shaw, R. S.; Chen, Charlie C.; Harris, Albert L.; Huang, Hui-Jou

    2009-01-01

    In recent years, rapid progress in the use of the internet has resulted in huge losses in many organizations due to lax security. As a result, information security awareness is becoming an important issue to anyone using the Internet. To reduce losses, organizations have made information security awareness a top priority. The three main barriers…

  17. Immune systems, geographic information systems (GIS), environment and health impacts.

    PubMed

    Blanco, Guillermo A; Cooper, Edwin L

    2004-01-01

    Exposure to dioxins, polychlorinated biphenyls (PCBs), and polycyclic aromatic hydrocarbons (PAHs) has been related to alterations in cellular and humoral immune responses in both adaptive and innate immune systems of most animal species. These compounds share a common signaling mechanism to exert their effects on cells of the immune system, which includes the aryl-hydrocarbon receptor (AhR) and the AhR nuclear translocator (ARN). Recently, the interference of AhR-ARNT with the nuclear factor (NF)-kappaB signaling pathway has been proposed as a critical event in the adverse effects on the immune system. Studies on the effects of these AhR-ARNT-related toxicants on the immune system of higher and lower phylum animals and knowledge of intracellular mechanisms of toxicity may contribute to development of biomarkers of ecotoxicant exposure and effects. Biomarkers of this kind allow sampling over extended geographic areas, in several sentinel species, including wildlife animals, and facilitate the building of risk models and risk maps of environmentally induced diseases. On the basis of location, biomarker sampled data obtained through evaluation of ecotoxicant exposure and effects on the immune system in sentinel species can be further integrated and analyzed together with other sources of environmental geographic information, or human population health data, by means of geographic information systems (GIS). The spatial analysis capability of GIS can help to evaluate the complex relationships of overlaid information and to identify areas with high risk indices or "hot spots." This integrative approach can be useful in studies contributing to support environmental and health-related policies and regulations.

  18. Diffusion-Weighted MRI for Nodal Staging of Head and Neck Squamous Cell Carcinoma: Impact on Radiotherapy Planning

    SciTech Connect

    Dirix, Piet; Vandecaveye, Vincent; De Keyzer, Frederik; Op de beeck, Katya; Poorten, Vincent Vander; Delaere, Pierre; Verbeken, Eric; Hermans, Robert; Nuyts, Sandra

    2010-03-01

    Purpose: To evaluate the use of diffusion-weighted magnetic resonance imaging (DW-MRI) for nodal staging and its impact on radiotherapy (RT) planning. Methods and Materials: Twenty-two patients with locally advanced head and neck squamous cell carcinoma underwent contrast-enhanced computed tomography (CT), as well as MRI (with routine and DW sequences) prior to neck dissection. After topographic correlation, lymph nodes were evaluated microscopically with prekeratin immunostaining. Pathology results were correlated with imaging findings and an RT planning study was performed for these surgically treated patients. One set of target volumes was based on conventional imaging only, and another set was based on the corresponding DW-MRI images. A third reference set was contoured based solely on pathology results. Results: A sensitivity of 89% and a specificity of 97% per lymph node were found for DW-MRI. Nodal staging agreement between imaging and pathology was significantly stronger for DW-MRI (kappa = 0.97; 95% confidence interval [CI], 0.84-1.00) than for conventional imaging (kappa = 0.56; 95% CI, 0.16-0.96; p = 0.019, by McNemar's test). For both imaging modalities, the absolute differences between RT volumes and those obtained by pathology were calculated. Using an exact paired Wilcoxon test, the observed difference was significantly larger for conventional imaging than for DW-MRI for nodal gross tumor volume (p = 0.0013), as well as for nodal clinical target volume (p = 0.0415) delineation. Conclusions: These results suggest that DW-MRI is superior to conventional imaging for preradiotherapy nodal staging of head and neck squamous cell carcinoma, and provides a potential impact on organsparing and tumor control.

  19. Information Literacy in a Digital Era: Understanding the Impact of Mobile Information for Undergraduate Nursing Students.

    PubMed

    Doyle, Glynda J; Furlong, Karen E; Secco, Loretta

    2016-01-01

    Recent entry-to-practice nursing informatics competencies for Registered Nurses in Canada mean nurse educators need educational strategies to promote student competency within the rapidly evolving informatics field. A collaborative research team from three Canadian nursing programs completed a mixed method survey to describe how nursing students used mobile nursing information support and the extent of this support for learning. The Mobile Information Support Evaluation Tool (MISET) assessed Usefulness/Helpfulness, Information Literacy Support, and Use of Evidence-Based Sources. The quantitative and qualitative data were analyzed to describe students' perspectives and the ways they used mobile resources in learning situations. Findings suggest nursing students mainly accessed mobile resources to support clinical learning, and specifically for task-oriented information such as drug medication or patient conditions/diagnoses. Researchers recommend a paradigm shift whereby educators emphasize information literacy in a way that supports evidence-based quality care.

  20. Impact of Different Analytic Approaches on the Analysis of the Breast Fibroglandular Tissue Using Diffusion Weighted Imaging

    PubMed Central

    Choi, Yoon Jung; Yu, Hon J.; Li, Yifan

    2017-01-01

    Purpose. This study investigated the impact of the different region of interest (ROI) approaches on measurement of apparent diffusion coefficient (ADC) values in the breast firbroglandular tissue (FT). Methods. Breast MR images of 38 women diagnosed with unilateral breast cancer were studied. Percent density (PD) and ADC were measured from the contralateral normal breast. Four different ROIs were used for ADC measurement. The measured PD and ADC were correlated. Results. Among the four ROIs, the manually placed small ROI on FT gave the highest mean ADC (ADC = 1839 ± 343 [×10−6 mm2/s]), while measurement from the whole breast gave the lowest mean ADC (ADC = 933 ± 383 [×10−6 mm2/s]). The ADC measured from the whole breast was highly correlated with PD with r = 0.95. In slice-to-slice comparison, the central slices with more FT had higher ADC values than the peripheral slices did, presumably due to less partial volume effect from fat. Conclusions. Our results indicated that the measured ADC heavily depends on the composition of breast tissue contained in the ROI used for the ADC measurements. Women with low breast density showing lower ADC values were most likely due to the partial volume effect of fatty tissues. PMID:28349054

  1. Improving the Accuracy of the Institute for Scientific Information's Journal Impact Factors.

    ERIC Educational Resources Information Center

    Moed, H. F.; Van Leeuwen, T. N.

    1995-01-01

    Discussion of impact factors of scientific journals focuses on a study that examined the Institute for Scientific Information's annual listing based upon data from the Science Citation Index. This article presents evidence that the values of the impact factors are often inaccurate due to an inappropriate definition of citable documents.…

  2. The Impact of Information and Communication Technology (ICT) on the Management Practices of Malaysian Smart Schools

    ERIC Educational Resources Information Center

    Zain, Muhammad Z. M.; Atan, Hanafi; Idrus, Rozhan M.

    2004-01-01

    The impact of Information and Communication Technology (ICT) on the management practices in the Malaysian Smart Schools was investigated. The analysis revealed that the impact has resulted in changes that include the enrichment of the ICT culture among students and teachers, more efficient student and teacher administration, better accessibility…

  3. Impact of Noncaregiving-Related Stressors on Informal Caregiver Outcomes.

    PubMed

    Austrom, Mary Guerriero; Lu, Yvonne Yueh-Feng; Perkins, Anthony J; Boustani, Malaz; Callahan, Christopher M; Hendrie, Hugh C

    2014-08-01

    Caregivers of persons with dementia are stressed. Stressors not related to care recipients' needs impact caregiver outcomes, yet are seldom reported. The purpose of this study was to report the most stressful events experienced by spouse caregivers of older adults with Alzheimer s disease during a 6-month period. 31 caregivers completed the Most Stressful Event form, Patient Health Questionnaire (PHQ-9) and the Revised Memory Behavioral Problem Checklist (R-MBPC). Fisher's exact test and two-sample t-test were used to compare Most Stressful Events between caregivers. ANOVA model tested whether the PHQ-9 and R-MBPC subscales differed by stressor. Caregivers reported no stressors 21.5% of the time, 1-2 stressors 25% of the time, and 3 stressors 53% of the time with 318 stressors reported in total. Care recipient needs (30.2%), caregiver needs (26.7%), and decision-making (16.7%) were the most frequently reported stressors. Using a mixed effects model, there were associations between the Most Stressful Events and depression (p = 0.016), mobility (p = 0.024) and caregiver issues (p = 0.009) subscales of R-MBPC. Results can be used to develop targeted intervention and support strategies for spouse caregivers experiencing non-caregiving related stressorsas well as the traditional challenges with caregiving related issues. © The Author(s) 2014.

  4. College Students' Health Information Activities on Facebook: Investigating the Impacts of Health Topic Sensitivity, Information Sources, and Demographics.

    PubMed

    Syn, Sue Yeon; Kim, Sung Un

    2016-07-01

    College students tend to lack access to health information. Because social networking sites (SNSs) are popularly adopted by college students, SNSs are considered to be good media channels for college students to obtain health-related information. This study examines the factors that influence college students' health information-seeking and -sharing activities on Facebook. An online survey was distributed to college students between the ages of 18 and 29 to determine intentions pertaining to health information activities according to the factors identified for the study. The factors included both contextual factors (such as health topic sensitivity and health information sources) as well as user factors (such as demographics). Our findings showed that college students are willing to read and post health-related information on Facebook when the health topic is not sensitive. In addition, there are clear differences in preferences between professional sources and personal sources as health information sources. It was found that most user factors, except gender, have no influence on health information activities. The impacts of SNS contexts, awareness of information sources, types of interlocutors, and privacy concerns are further discussed.

  5. The Impact of Internet Health Information on Patient Compliance: A Research Model and an Empirical Study

    PubMed Central

    Hassanein, Khaled; Yuan, Yufei

    2015-01-01

    Background Patients have been increasingly seeking and using Internet health information to become more active in managing their own health in a partnership with their physicians. This trend has both positive and negative effects on the interactions between patients and their physicians. Therefore, it is important to understand the impact that the increasing use of Internet health information has on the patient-physician relationship and patients’ compliance with their treatment regimens. Objective This study examines the impact of patients’ use of Internet health information on various elements that characterize the interactions between a patient and her/his physician through a theoretical model based on principal-agent theory and the information asymmetry perspective. Methods A survey-based study consisting of 225 participants was used to validate a model through various statistical techniques. A full assessment of the measurement model and structural model was completed in addition to relevant post hoc analyses. Results This research revealed that both patient-physician concordance and perceived information asymmetry have significant effects on patient compliance, with patient-physician concordance exhibiting a considerably stronger relationship. Additionally, both physician quality and Internet health information quality have significant effects on patient-physician concordance, with physician quality exhibiting a much stronger relationship. Finally, only physician quality was found to have a significant impact on perceived information asymmetry, whereas Internet health information quality had no impact on perceived information asymmetry. Conclusions Overall, this study found that physicians can relax regarding their fears concerning patient use of Internet health information because physician quality has the greatest impact on patients and their physician coming to an agreement on their medical situation and recommended treatment regimen as well as

  6. The Impact of Internet Health Information on Patient Compliance: A Research Model and an Empirical Study.

    PubMed

    Laugesen, John; Hassanein, Khaled; Yuan, Yufei

    2015-06-11

    Patients have been increasingly seeking and using Internet health information to become more active in managing their own health in a partnership with their physicians. This trend has both positive and negative effects on the interactions between patients and their physicians. Therefore, it is important to understand the impact that the increasing use of Internet health information has on the patient-physician relationship and patients' compliance with their treatment regimens. This study examines the impact of patients' use of Internet health information on various elements that characterize the interactions between a patient and her/his physician through a theoretical model based on principal-agent theory and the information asymmetry perspective. A survey-based study consisting of 225 participants was used to validate a model through various statistical techniques. A full assessment of the measurement model and structural model was completed in addition to relevant post hoc analyses. This research revealed that both patient-physician concordance and perceived information asymmetry have significant effects on patient compliance, with patient-physician concordance exhibiting a considerably stronger relationship. Additionally, both physician quality and Internet health information quality have significant effects on patient-physician concordance, with physician quality exhibiting a much stronger relationship. Finally, only physician quality was found to have a significant impact on perceived information asymmetry, whereas Internet health information quality had no impact on perceived information asymmetry. Overall, this study found that physicians can relax regarding their fears concerning patient use of Internet health information because physician quality has the greatest impact on patients and their physician coming to an agreement on their medical situation and recommended treatment regimen as well as patient's compliance with their physician's advice when

  7. Experiments in Discourse Analysis Impact on Information Classification and Retrieval Algorithms.

    ERIC Educational Resources Information Center

    Morato, Jorge; Llorens, J.; Genova, G.; Moreiro, J. A.

    2003-01-01

    Discusses the inclusion of contextual information in indexing and retrieval systems to improve results and the ability to carry out text analysis by means of linguistic knowledge. Presents research that investigated whether discourse variables have an impact on information and retrieval and classification algorithms. (Author/LRW)

  8. Finding Useful Questions: On Bayesian Diagnosticity, Probability, Impact, and Information Gain

    ERIC Educational Resources Information Center

    Nelson, Jonathan D.

    2005-01-01

    Several norms for how people should assess a question's usefulness have been proposed, notably Bayesian diagnosticity, information gain (mutual information), Kullback-Liebler distance, probability gain (error minimization), and impact (absolute change). Several probabilistic models of previous experiments on categorization, covariation assessment,…

  9. The Impact of Computers on the Retrieval and Utilization of Chemical Information.

    ERIC Educational Resources Information Center

    Lawrence, Barbara

    The use of computers in retrieving bibliographic chemical information is traced through the SDI, batch, and online modes, and related changes are noted in such areas as data base availability, cost, software, and amount of user control. The impact of these changes on both the quality and quantity of chemical information use is discussed, as well…

  10. The Impact of Computers on the Retrieval and Utilization of Chemical Information.

    ERIC Educational Resources Information Center

    Lawrence, Barbara

    The use of computers in retrieving bibliographic chemical information is traced through the SDI, batch, and online modes, and related changes are noted in such areas as data base availability, cost, software, and amount of user control. The impact of these changes on both the quality and quantity of chemical information use is discussed, as well…

  11. Measuring the impact of information skills training: a survey of health libraries in England.

    PubMed

    Ayre, Stephen; Barbrook, John; Engel, Colin; Lacey, Patricia; Phul, Anita; Stevenson, Paul; Toft, Suzanne

    2015-03-01

    The lack of robust research measuring the impact of NHS based information skills training prompted the West Midlands Regional Trainers' Forum to conduct a post-training survey. This is a multi-centred study which collected data from over 60 separate organisations. Survey questionnaires were completed by learners a few weeks after the training event. Five hundred and thirty-four responses were received. 82% of information skills training recipients indicated that they had implemented learning or changed practice as a result of the training. 70% of recipients indicated there had been an impact on patient care. The beneficial results from information skills training manifest in a multitude of ways. The results of this study indicate that the learning from information skills training is being used to reduce problems and address the key issues in modern health care. The results clearly demonstrate the value of information skills training and its beneficial impact on patient care, lifelong learning and other key NHS functions. This study shows information skills training as an important activity which supports the information literacy agenda, and has a positive impact across the four key functions of library and knowledge services within the NHS. © 2014 The authors. Health Information and Libraries Journal © 2014 Health Libraries Journal.

  12. The Impact of Informal Mentoring: Perceptions of Alumni of Evangelical Theological Schools in Indonesia

    ERIC Educational Resources Information Center

    Sumule, Leonard

    2016-01-01

    This grounded theory study explores the perceptions of 33 alumni of 10 Indonesian evangelical theological schools regarding the impact of informal mentoring, which they experienced during their time as students. Data from face-to-face interviews revealed that the informal mentoring relationships (a) helped them to handle their social and emotional…

  13. The Impact of Informal Mentoring: Perceptions of Alumni of Evangelical Theological Schools in Indonesia

    ERIC Educational Resources Information Center

    Sumule, Leonard

    2016-01-01

    This grounded theory study explores the perceptions of 33 alumni of 10 Indonesian evangelical theological schools regarding the impact of informal mentoring, which they experienced during their time as students. Data from face-to-face interviews revealed that the informal mentoring relationships (a) helped them to handle their social and emotional…

  14. A Multidimensional Theoretical Analysis of the Impact of Information Technology on Higher Education.

    ERIC Educational Resources Information Center

    Bair, Miles

    The widespread use of Information Technology (IT) in a college or university setting represents a significant change from traditional ways in which higher education has been conducted. Technological change has repercussions throughout the many dimensions of institutional life. This paper explores the impact of information technology on the…

  15. Competence and Affect in Task Involvement and Ego Involvement: The Impact of Social Comparison Information.

    ERIC Educational Resources Information Center

    Jagacinski, Carolyn M.; Nicholls, John G.

    1987-01-01

    Two studies investigated the impact of information about the effort and performance of others on students' anticipated affects and judgments of competence given success in task-involving and ego-involving contexts. Without social comparison information, competence and positive affects were judged higher when students were asked to imagine…

  16. Experiments in Discourse Analysis Impact on Information Classification and Retrieval Algorithms.

    ERIC Educational Resources Information Center

    Morato, Jorge; Llorens, J.; Genova, G.; Moreiro, J. A.

    2003-01-01

    Discusses the inclusion of contextual information in indexing and retrieval systems to improve results and the ability to carry out text analysis by means of linguistic knowledge. Presents research that investigated whether discourse variables have an impact on information and retrieval and classification algorithms. (Author/LRW)

  17. Community Participation in Public Schools: Impact of Information Campaigns in Three Indian States

    ERIC Educational Resources Information Center

    Pandey, Priyanka; Goyal, Sangeeta; Sundararaman, Venkatesh

    2009-01-01

    This study evaluates the impact of a community-based information campaign on school performance from a cluster randomized control trial in 610 villages. The campaign consisted of eight or nine public meetings in each of 340 treatment villages across three Indian states to disseminate information to the community about its state-mandated roles and…

  18. 76 FR 43264 - Proposed Information Collection; Comment Request; NIST MEP Client Impact Survey

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-07-20

    ... National Institute of Standards and Technology Proposed Information Collection; Comment Request; NIST MEP Client Impact Survey AGENCY: National Institute of Standards and Technology (NIST), Commerce. ACTION...@nist.gov . SUPPLEMENTARY INFORMATION: I. Abstract Sponsored by the National Institute of Standards and...

  19. Designing a Software for Flood Risk Assessment Based on Multi Criteria Desicion Analysis and Information Diffusion Methods

    NASA Astrophysics Data System (ADS)

    Musaoglu, N.; Saral, A.; Seker, D. Z.

    2012-12-01

    Flooding is one of the major natural disasters not only in Turkey but also in all over the world and it causes serious damage and harm. It is estimated that of the total economic loss caused by all kinds of disasters, 40% was due to floods. In July 1995, the Ayamama Creek in Istanbul was flooded, the insurance sector received around 1,200 claims notices during that period, insurance companies had to pay a total of $40 million for claims. In 2009, the same creek was flooded again and killed 31 people over two days and insurance firms paid for damages around cost €150 million for claims. To solve these kinds of problems modern tools such as GIS and Remote Sensing should be utilized. In this study, a software was designed for the flood risk analysis with Analytic Hierarchy Process (AHP) and Information Diffusion( InfoDif) methods.In the developed sofware, five evaluation criterias were taken into account, which were slope, aspect, elevation, geology and land use which were extracted from the satellite sensor data. The Digital Elevation Model (DEM) of the Ayamama River Basin was acquired from the SPOT 5 satellite image with 2.5 meter spatial resolution. Slope and aspect values of the study basin were extracted from this DEM. The land use of the Ayamama Creek was obtained by performing object-oriented nearest neighbor classification method by image segmentation on SPOT 5 image dated 2010. All produced data were used as an input for the part of Multi Criteria Desicion Analysis (MCDA) method of this software. Criterias and their each sub criteras were weighted and flood vulnerability was determined with MCDA-AHP. Also, daily flood data was collected from Florya Meteorological Station, between 1975 to 2009 years and the daily flood peak discharge was calculated with the method of Soil Conservation Service-Curve Number (SCS-CN) and were used as an input in the software for the part of InfoDif.Obtained results were verified using ground truth data and it has been clearly

  20. Impact of contact pressure-induced spectral changes on soft-tissue classification in diffuse reflectance spectroscopy: problems and solutions.

    PubMed

    Cugmas, Blaž; Bregar, Maksimilijan; Bürmen, Miran; Pernuš, Franjo; Likar, Boštjan

    2014-03-01

    Review of the existing studies on the contact pressure-induced changes in the optical properties of biological tissues showed that the reported changes in transmittance, reflectance, absorption, and scattering coefficient are vastly inconsistent. In order to gain more insight into the contact pressure-induced changes observed in biomedical applications involving common probe-spectrometer diffuse reflectance measurement setups and provide a set of practical guidelines minimizing the influence of the changes on the analysis of acquired spectra, we conducted a series of in vivo measurements, where the contact pressure was precisely controlled, and the spectral and contact pressure information were acquired simultaneously. Classification of three measurement sites on a human hand, representing the natural variability in the perfusion and structure of the underlying tissue, was assessed by training and evaluating classifiers at different contact pressure levels and for different probe operators. Based on the results, three practical guidelines have been proposed to avoid classification performance degradation. First, the most suitable pressure level should be identified. Second, the pressure level should be kept in a narrow range during the acquisition of spectra. Third, applications utilizing probes equipped with a calibrated spring can use several classifiers trained at different contact pressure levels to improve classification performance.

  1. Impacts of hospitals' innovativeness on information system outsourcing decisions.

    PubMed

    Park, Jae Sung

    2014-04-01

    The purpose of this study was to identify the effects of hospitals' innovativeness on outsourcing decision-making regarding four information system (IS) functions, namely, software programs, network maintenance, hardware systems, and PC/printer maintenance. Using the 2011 roster of the Korean Hospital Association, this study selected 311 general hospitals as a study population. After identifying the managers who were in charge of outsourcing, this study administered questionnaires. A total of 103 hospitals responded. Of the responding hospitals, 55.34% outsourced at least one IS function, whereas 88.35% outsourced at least one managerial function. IS outsourcing was motivated by the need for outside experts, but other managerial functions were outsourced for cost savings. Innovative and early adopter hospitals were 4.52 and 4.91 times more likely to outsource IS functions related with work processes (i.e., software and network maintenance) than early and late majority hospitals, respectively. IT outsourcing effectiveness significantly influenced the outsourcing decisions regarding four IS functions. Hospitals that had perceived more risks of outsourcing significantly preferred non-outsourcing on their hardware systems, but the risks of outsourcing were not significant for outsourcing decisions regarding the other IS functions. Hospitals' innovativeness also significantly explained the quantity of innovation adoptions. Innovative and early adopter hospitals did more outsourcing than early and late majority hospitals. Hospitals' innovativeness influences decision-making regarding outsourcing. Innovative hospitals are more likely to outsource their work-process-related IS functions. Thus, organizational traits, especially hospitals' innovativeness, should be considered as a key success factor for IS management.

  2. Impacts of Hospitals' Innovativeness on Information System Outsourcing Decisions

    PubMed Central

    2014-01-01

    Objectives The purpose of this study was to identify the effects of hospitals' innovativeness on outsourcing decision-making regarding four information system (IS) functions, namely, software programs, network maintenance, hardware systems, and PC/printer maintenance. Methods Using the 2011 roster of the Korean Hospital Association, this study selected 311 general hospitals as a study population. After identifying the managers who were in charge of outsourcing, this study administered questionnaires. A total of 103 hospitals responded. Results Of the responding hospitals, 55.34% outsourced at least one IS function, whereas 88.35% outsourced at least one managerial function. IS outsourcing was motivated by the need for outside experts, but other managerial functions were outsourced for cost savings. Innovative and early adopter hospitals were 4.52 and 4.91 times more likely to outsource IS functions related with work processes (i.e., software and network maintenance) than early and late majority hospitals, respectively. IT outsourcing effectiveness significantly influenced the outsourcing decisions regarding four IS functions. Hospitals that had perceived more risks of outsourcing significantly preferred non-outsourcing on their hardware systems, but the risks of outsourcing were not significant for outsourcing decisions regarding the other IS functions. Hospitals' innovativeness also significantly explained the quantity of innovation adoptions. Innovative and early adopter hospitals did more outsourcing than early and late majority hospitals. Conclusions Hospitals' innovativeness influences decision-making regarding outsourcing. Innovative hospitals are more likely to outsource their work-process-related IS functions. Thus, organizational traits, especially hospitals' innovativeness, should be considered as a key success factor for IS management. PMID:24872912

  3. Comparing narrative versus numerical display of functional information: impact on sense-making.

    PubMed

    Weir, Charlene; Dunlea, Robert; Staggers, Nancy; Dooing-Harris, Kristina; Mccormick, Teresa; Barrus, Robyn

    2014-01-01

    Contextual information consists of functional, social, and financial information about patients. Physicians routinely have difficulty incorporating contextual information into clinical decision-making despite the emphasis on patient-centered care and functional status. One reason for this difficulty is that such information is not well-represented in the patient medical record. This study assesses the impact of a "story-form" model versus a "medical" model on a practitioner's ability to recall and incorporate contextual information. We assessed this question through the analysis of responses of 30 clinicians to 2 vignettes presenting contextual information in both formats. Overall, there was a statistically significant difference between the narrative and numerical form with those receiving the narrative form for contextual information being more likely to consider it a top issue. Reference to goals in the report of key clinical factors was also significantly higher for the group receiving goal information. Implications for sharing contextual information in EMRs are discussed.

  4. Barcode technology in blood bank information systems: upgrade and its impact.

    PubMed

    Li, Bing Nan; Chao, Sam; Dong, Ming Chui

    2006-12-01

    This paper desires to explore the role of barcode technology in blood bank information systems via addressing its upgrade and the consequent impact. Firstly, it briefs the application and effect of barcode technology in blood donation and transfusion service. In the second, the barcode paradigms of Macau Codabar and ISBT 128 are carefully examined and compared in accordance with the procedure and specifications of barcode upgrade. Then, the impact due to upgrade is assessed from the perspectives of blood bank information system, blood banks, and even blood donation and transfusion service. It finally discusses the considerations on implementing the upgrade of barcode technology in blood bank information systems.

  5. Iterative positioning algorithm to reduce the impact of diffuse reflection on an indoor visible light positioning system

    NASA Astrophysics Data System (ADS)

    Huang, Heqing; Feng, Lihui; Guo, Peng; Yang, Aiying; Ni, Guoqiang

    2016-06-01

    Recently, indoor visible light localization has become attractive. Unfortunately, its performance is limited by diffuse reflection. The diffuse reflection is estimated by the bilinear interpolation-based method. A received signal strength-based iterative visible light positioning algorithm is proposed to reduce the influence of diffuse reflection by subtracting the estimated diffuse reflection signal from the received signal. Simulations are made to evaluate the proposed iterative positioning algorithm in a typical scenario with different parameters of the field-of-view (FOV) of the receiver and the reflectivity of the wall. Results show that the proposed algorithm can reduce the average positioning error by 12 times in a typical scenario and can reduce the positioning error greatly with various FOV of the receiver and the reflectivity of the wall. The proposed algorithm is effective and robust to reduce the degradation caused by diffuse reflection in a positioning system and will have many potential applications in indoor localization scenarios.

  6. Clinical efficacy of Yingliu mixture combined with metimazole for treating diffuse goitre with hyperthyroidism and its impact on related cytokines.

    PubMed

    Yang, Hua; Cong, Yilei; Wu, Tengfei; Tang, Hong; Ma, Muhao; Zeng, Juanhua; Zhang, Wenya; Lian, Zhen; Yang, Xinyu

    2017-12-01

    Yingliu mixture was developed in 1990s by Affiliated Longhua Hospital of Shanghai University of Traditional Chinese Medicine, for treating diffuse goitre with hyperthyroidism (Graves' disease, GD). Former studies have shown Yingliu mixture combined with methimazole (Y-M) can effectively improve thyroid function and decrease thyrotropin-receptor antibody level. Furthermore, we researched its impact on related cytokines to prove that Y-M improve patients' immunity status. To observe the clinical efficacy of Y-M for treating GD. A total of 120 GD patients were randomly divided into two groups, the treatment and the control groups (n = 60). The treatment group's patients were treated with Y-M. The control group's patients were treated with methimazole alone. Yingliu mixture was orally administered, 25 mL three times daily. Methimazole was administered at 5-25 mg/day. After 12 weeks of the treatment, the cytokines, antibodies related to thyroid function, and Chinese medical syndromes were evaluated. After the treatment, the free triiodothyronine and thyroxine levels in both groups decreased. The thyroid-stimulating hormone level increased in the treatment group. The thyrotropin-receptor antibody levels and TNF-α levels decreased in both groups. In the control group, IL-6 and IFN-γ levels were lower than that before the treatment. In the treatment group, CD4(+) and CD25(+) levels were higher than pretreatment levels, but IL-10 levels were reduced. the total CMS scores for both groups decreased. The Y-M combination can improve thyroid function, and decrease autoantibodies, cytokines, and clinical symptoms, so its efficacy may surpass that of methimazole alone.

  7. Impact of diffusion-weighted imaging Alberta stroke program early computed tomography score on the success of endovascular reperfusion therapy.

    PubMed

    Inoue, Manabu; Olivot, Jean-Marc; Labreuche, Julien; Mlynash, Michael; Tai, Waimea; Albucher, Jean-François; Meseguer, Elena; Amarenco, Pierre; Mazighi, Mikael

    2014-07-01

    In acute ischemic stroke patients treated by intravenous thrombolysis, a diffusion-weighted imaging (DWI) Alberta Stroke Program Early Computed Tomography Score (ASPECTS) is an independent factor of functional outcomes. Our aim was to assess the impact of pretreatment DWI-ASPECTS on outcomes after endovascular therapy, with a specific emphasis on recanalization. We analyzed data collected between April 2007 and March 2013 in a prospective clinical registry of acute ischemic stroke patients treated by endovascular approach. Every patient with a documented internal carotid artery or middle cerebral artery occlusion who underwent an acute DWI-MRI before treatment was eligible for this study. The primary outcome was a favorable outcome defined by modified Rankin Scale of 0 to 2 at 90 days. Two hundred ten patients were included and median DWI-ASPECTS was 7 (interquartile range, 4-8). DWI-ASPECTS≥5 was the optimal threshold to predict a favorable outcome (area under the curve=0.69; sensitivity, 90%; specificity, 38%). In a multivariate analysis including confounding variables, the adjusted odds ratio for favorable outcomes associated with a DWI-ASPECTS of ≥5 was 5.06 (95% confidence interval, 1.86-13.77; P=0.002). Nonetheless, the occurrence of a complete recanalization was associated with an increased rate of favorable outcomes in patients with DWI-ASPECTS under 5 (50% versus 3%, P<0.001). DWI-ASPECTS≥5 seems to be the optimal threshold to predict favorable outcomes among patients undergoing endovascular reperfusion within 6 hours. Selected patients with a DWI-ASPECTS of <5 may still benefit when a complete reperfusion is achieved. © 2014 American Heart Association, Inc.

  8. Leveraging Informal Leadership in Higher Education Institutions: A Case of Diffusion of Emerging Technologies in a Southern Context

    ERIC Educational Resources Information Center

    Ng'ambi, Dick; Bozalek, Vivienne

    2013-01-01

    In the last decade, emerging technologies and transformative practices have diffused into higher education social systems in ways that formal leadership styles are increasingly stretched to both keep abreast of and to manage. While many scholars have argued for the importance of the role of leadership styles in shaping the strategic direction of…

  9. Measuring the value and impact of health library and information services: past reflections, future possibilities.

    PubMed

    Marshall, Joanne Gard

    2007-12-01

    To summarize the context, history and results of research studies conducted on the value and impact of health library and information services by the author since 1975 and to use this as a basis for examining ongoing developments related to evaluation research. To provide a comprehensive bibliography of library value and impact studies. Literature review and background based on personal involvement in the studies under discussion. The author's studies demonstrate an ongoing evolution of value and impact studies since the mid-1970s. In health sciences libraries, the approach taken to measuring value and impact has been strongly influenced by the type of research being conducted in the health sciences field as a whole. As a result, health sciences library researchers have become early adopters of methods that incorporate outcome and impact measures and rigorous research designs, and the concept of evidence-based library and information practice. The paper recommends that a range of research approaches from various disciplines be used to guide future evaluation research. Value and impact studies will continue to be important resources for evidence-based practice as health information professionals deal with evolving user needs and new ways of delivering information to a variety of audiences.

  10. Exploring the impact of health information technology on communication and collaboration in acute care nursing.

    PubMed

    Cashen, Margaret S; Bradley, Victoria; Farrell, Ann; Murphy, Judy; Schleyer, Ruth; Sensmeier, Joyce; Dykes, Patricia C

    2006-01-01

    A focus group using nursing informatics experts as informants was conducted to guide development of a survey to explore the impact of health information technology on the role of nurses and interdisciplinary communication in acute care settings. Through analysis of focus group transcripts, five key themes emerged: information, communication, care coordination, interdisciplinary relationships, workflow, and practice effectiveness and efficiency. This served as the basis for development of a survey that will investigate perceptions of acute care providers across the United States regarding the impact of health information technology on the role of nurses and interdisciplinar communication in acute care settings. The purpose of this paper is to describe the process of survey development including analysis of transcripts, emergence of key themes, and the processes by which the themes will be employed to inform survey development.

  11. Impact of bilingual product information labels on Spanish-speaking adults' ability to comprehend OTC information.

    PubMed

    Sansgiry, Sujit S; Chanda, Surupa; Shringarpure, Gauri S

    2007-12-01

    There is a steady growth in the Spanish-speaking population in the United States. Language may be a barrier in accessing nonprescription medication information for the non-English-speaking population. The objective of this study was to compare consumer-reported ease of use, product knowledge, and intention to purchase over-the-counter (OTC) medications using bilingual Product Information Labels (PILs) and currently available label formats in a sample of Spanish-speaking consumers. Participants were randomly selected from Spanish-speaking consumers shopping for OTC medications in pharmacy or grocery stores in Houston, TX. Participants viewed 3 label formats (old, new, and PILs) for acetaminophen, ibuprofen, and aspirin in a random order. Questionnaires in English and in Spanish were provided to consumers after they viewed each label format. Domains measured in the questionnaires included ease of use, product knowledge, and purchase intention. All responses were measured on a 7-point Likert-type scale. Data were recoded and analyzed using SAS (version 9.0) (SAS Institute Inc, Cary, NC) to obtain mean scores for each domain. Participants were classified according to language proficiency into "Spanish only" and bilinguals. Comparative statistics were computed to compare mean scores between label formats in each consumer category. A total of 225 questionnaires were collected. The mean (+/-standard deviation) age of participants was 38.91 (+/-11.95) years. A majority of respondents were Hispanic (97.75%), female (60.54%), and married (62.44%). Mean scores from viewing PILs on ease of use, product knowledge, and purchase intention were higher than those from viewing the other label formats. In the category of consumers who spoke Spanish only, mean scores of PILs were significantly higher as compared to those of old and new label formats (P<.05). Information provided in Spanish on PILs may be very helpful to the Spanish-speaking community when selecting nonprescription

  12. Impact of the information age on residency training: communication, access to public information, and clinical care.

    PubMed

    Hilty, Donald M; Belitsky, Richard; Cohen, Mitchell B; Cabaniss, Deborah L; Dickstein, Leah J; Bernstein, Carol A; Kaplan, Allan S; Scheiber, Stephen C; Crisp-Han, Holly D; Wrzosek, Marika I; Silberman, Edward K

    2015-02-01

    Access to technology in practice helps physicians manage information, communicate, and research topics; however, those in training receive almost no formal preparation for integrating web-based technologies into practice. One reason for this is that many faculty-aside from junior faculty or those in recent generations-did not grow up using Internet communication, may use it minimally, if at all, in their own practices, and may know little about its forms and varieties. This report presents a case to illustrate how these disparities may play out in the supervisory situation and makes suggestions about helping supervisors integrate technology-awareness into their teaching.

  13. NASA/DOD Aerospace Knowledge Diffusion Research Project. Report 34: How early career-stage US aerospace engineers and scientists produce and use information

    NASA Technical Reports Server (NTRS)

    Pinelli, Thomas E.; Barclay, Rebecca O.; Kennedy, John M.

    1995-01-01

    The U.S. government technical report is a primary means by which the results of federally funded research and development (R&D) are transferred to the U.S. aerospace industry. However, little is known about this information product in terms of its actual use, importance, and value in the transfer of federally funded R&D. To help establish a body of knowledge, the U.S. government technical report is being investigated as part of the NASA/DOD Aerospace Knowledge Diffusion Research Project. In this report, we summarize the literature on technical reports and provide a model that depicts the transfer of federally funded aerospace R&D via the U.S. government technical report. We present results from our investigation of aerospace knowledge diffusion vis-a-vis the U.S. government technical report, and present the results of research that investigated aerospace knowledge diffusion vis-a-vis the production and use of information by U.S. aerospace engineers and scientists who had changed their American Institute of Aeronautics and Astronautics (AIAA) membership from student to professional in the past five years.

  14. The Impact of Buoyancy and Flame Structure on Soot, Radiation and NOx Emissions from a Turbulent Diffusion Flame

    NASA Technical Reports Server (NTRS)

    Kennedy, I. M.; Kollman, W.; VanderWal, R. L.

    1999-01-01

    It is hypothesized that the spatial structure of a turbulent diffusion flame plays an important role in determining the emissions of radiative energy, soot and NO, from a combustor. This structure, manifested in the two point statistics, is influenced by buoyancy. Radiation, soot and NOx emissions are the cumulative result of processes that occur throughout a flame. For example, radiation fluxes along a line of sight can be found from summing up the contributions from sources in individual pockets of hot soot that emit, and from sinks in cold soot that absorb. Soot and NOx are both the results of slow chemistry and are not equilibrium products. The time that is available for production and burnout is crucial in determining the eventual emissions of these pollutants. Turbulence models generally rely on a single point closure of the appropriate time averaged equations. Hence, spatial information is lost and needs to be modeled using solution variables such as turbulence kinetic energy and dissipation rate, often with the assumption of isotropy. However, buoyancy can affect the physical structure of turbulent flames and can change the spatial extent of soot bearing regions. Theoretical comparisons with models are best done in the limit of infinite Froude number because the inclusion of buoyancy in flow models introduces significant uncertainties. Hence, LII measurements of soot, measurements of radiation fluxes from soot, Particle Imaging Velocimetry (PIV) of the flow field and measurements of post flame NOX will be carried out on the NASA Lewis 2.2 sec drop tower and eventually on the parabolic flight aircraft. The drop rig will be a modified version of a unit that has been successfully used at Lewis in the past.

  15. The Impact of Buoyancy and Flame Structure on Soot, Radiation and NOx Emissions from a Turbulent Diffusion Flame

    NASA Technical Reports Server (NTRS)

    Kennedy, I. M.; Kollman, W.; VanderWal, R. L.

    1999-01-01

    It is hypothesized that the spatial structure of a turbulent diffusion flame plays an important role in determining the emissions of radiative energy, soot and NO, from a combustor. This structure, manifested in the two point statistics, is influenced by buoyancy. Radiation, soot and NOx emissions are the cumulative result of processes that occur throughout a flame. For example, radiation fluxes along a line of sight can be found from summing up the contributions from sources in individual pockets of hot soot that emit, and from sinks in cold soot that absorb. Soot and NOx are both the results of slow chemistry and are not equilibrium products. The time that is available for production and burnout is crucial in determining the eventual emissions of these pollutants. Turbulence models generally rely on a single point closure of the appropriate time averaged equations. Hence, spatial information is lost and needs to be modeled using solution variables such as turbulence kinetic energy and dissipation rate, often with the assumption of isotropy. However, buoyancy can affect the physical structure of turbulent flames and can change the spatial extent of soot bearing regions. Theoretical comparisons with models are best done in the limit of infinite Froude number because the inclusion of buoyancy in flow models introduces significant uncertainties. Hence, LII measurements of soot, measurements of radiation fluxes from soot, Particle Imaging Velocimetry (PIV) of the flow field and measurements of post flame NOX will be carried out on the NASA Lewis 2.2 sec drop tower and eventually on the parabolic flight aircraft. The drop rig will be a modified version of a unit that has been successfully used at Lewis in the past.

  16. Modeling the impact of formal and informal supports for young children with disabilities and their families.

    PubMed

    Bailey, Donald B; Nelson, Lauren; Hebbeler, Kathy; Spiker, Donna

    2007-10-01

    The purpose of this work was to examine factors related to perceived impact of early intervention on children with disabilities and their families. A nationally representative sample of approximately 2100 parents completed a 40-minute telephone interview near their child's third birthday. Structural equation modeling examined the relationships between 3 support variables (quality of child services, quality of family services, and family/community support) and 2 outcomes at 36 months (impact on child and impact on family) and determined whether these relationships were mediated by 2 perceptual variables (optimism and confidence in parenting) or moderated by 5 demographic variables (poverty, maternal education, ethnicity, age of initial Individual Family Service Plan, and health at 36 months). Perceived impact of early intervention on both child and family were significantly related to each other. The quality of child services was related to impact on the child but not on the family. The quality of family services was related to both child and family impact. Informal support was not related to perceived impact on children or families but was strongly related to confidence in parenting and optimism. Neither optimism nor confidence in parenting mediated the relationships between services or supports and perceived impact. Minority families and families of children with poor health reported lower quality of services, but these characteristics did not moderate the relationships between services and perceived impact on the child. However, both poverty status and minority status were associated with perceptions of impact on the family. Findings reinforce the role of high-quality services in maximizing perceived impact. They also highlight the important role of informal support in promoting optimism and confidence in parenting. Poverty status, minority status, and poor health of the child are salient factors in predicting lower perceived quality of and benefit from services.

  17. NASA/DOD Aerospace Knowledge Diffusion Research Project. Paper 13: The information-seeking habits and practices of engineers

    NASA Technical Reports Server (NTRS)

    Pinelli, Thomas E.

    1991-01-01

    It is argued that only by maximizing the research and development process can the United States maintain and possibly capture its international competitive edge. Key to this goal is the provision of information services and products which meet the information needs of engineers. Evidence exists which indicates that traditional information services and products may, in fact, not be meeting the information needs of engineers. The primary reason for this deficiency is three fold. First, the specific information needs of engineers are neither well known nor well understood. Second, what is known about the information seeking habits and practices of engineers has not been applied to existing engineering information services. Third, the information professionals continue to over-emphasize technology instead of concentrating on the quality of the information itself and the ability of the information to meet the needs of the user.

  18. Integrating prior information into microwave tomography part 2: Impact of errors in prior information on microwave tomography image quality.

    PubMed

    Kurrant, Douglas; Baran, Anastasia; LoVetri, Joe; Fear, Elise

    2017-09-17

    The authors have developed a method to combine a patient-specific map of tissue structure and average dielectric properties with microwave tomography. The patient-specific map is acquired with radar-based techniques and serves as prior information for microwave tomography. The impact that the degree of structural detail included in this prior information has on image quality was reported in a previous investigation. The aim of the present study is to extend this previous work by identifying and quantifying the impact that errors in the prior information have on image quality, including the reconstruction of internal structures and lesions embedded in fibroglandular tissue. This study also extends the work of others reported in literature by emulating a clinical setting with a set of experiments that incorporate heterogeneity into both the breast interior and glandular region, as well as prior information related to both fat and glandular structures. Patient-specific structural information is acquired using radar-based methods that form a regional map of the breast. Errors are introduced to create a discrepancy in the geometry and electrical properties between the regional map and the model used to generate the data. This permits the impact that errors in the prior information have on image quality to be evaluated. Image quality is quantitatively assessed by measuring the ability of the algorithm to reconstruct both internal structures and lesions embedded in fibroglandular tissue. The study is conducted using both 2D and 3D numerical breast models constructed from MRI scans. The reconstruction results demonstrate robustness of the method relative to errors in the dielectric properties of the background regional map, and to misalignment errors. These errors do not significantly influence the reconstruction accuracy of the underlying structures, or the ability of the algorithm to reconstruct malignant tissue. Although misalignment errors do not significantly impact

  19. Determination of partition and diffusion coefficients of formaldehyde in selected building materials and impact of relative humidity (journal)

    EPA Science Inventory

    The partition and effective diffusion coefficients of formaldehyde were measured for three materials (conventional gypsum wallboard, "green" gypsum wallboard, and "green" carpet) under three relative humidity (RH) conditions (20%, 50% and 70% RH). A dynamic dual-chamber test meth...

  20. Determination of partition and diffusion coefficient of formaldehyde in selected building materials and impact of relative humidity

    EPA Science Inventory

    The partition and effective diffusion coefficients of formaldehyde were measured for three materials (conventional gypsum wallboard, "green" gypsum wallboard, and "green" carpet) under three relative humidity (RH) conditions (20%, 50% and 70% RH). A dynamic dual-chamber test meth...

  1. Determination of partition and diffusion coefficients of formaldehyde in selected building materials and impact of relative humidity (journal)

    EPA Science Inventory

    The partition and effective diffusion coefficients of formaldehyde were measured for three materials (conventional gypsum wallboard, "green" gypsum wallboard, and "green" carpet) under three relative humidity (RH) conditions (20%, 50% and 70% RH). A dynamic dual-chamber test meth...

  2. Determination of partition and diffusion coefficient of formaldehyde in selected building materials and impact of relative humidity

    EPA Science Inventory

    The partition and effective diffusion coefficients of formaldehyde were measured for three materials (conventional gypsum wallboard, "green" gypsum wallboard, and "green" carpet) under three relative humidity (RH) conditions (20%, 50% and 70% RH). A dynamic dual-chamber test meth...

  3. Impact of the Freedom of Information Act on the National Intelligence Agencies.

    DTIC Science & Technology

    1982-04-16

    virtually all confidential information of the United States, whether military, diplomatic or economic, is transmitted at some time by secure communications ...in 1974, there was no major impact upon the day to day functioning of the Intelligence Community .1 Then, in 1974, during the post-Watergate period of...concern, however, in assessing the negative impact of FOIA on the national intel- ligence agencies. The Intelligence Community faces other problems

  4. Lignin and lipid impact on sorption and diffusion of trichloroethylene in tree branches for determining contaminant fate during plant sampling and phytoremediation.

    PubMed

    Gopalakrishnan, Gayathri; Burken, Joel G; Werth, Charles J

    2009-08-01

    Plants draw all they need from their surrounding environment and in doing so also draw anthropogenic contaminants from their surroundings. Several natural processes (e.g., active transport, diffusion, sorption, and degradation) occur within trees and affect chemical concentrations in tree samples. This study elucidates tree contaminant chemical interactions on equilibrium sorption and diffusion into branch tissue (i.e., wood core and bark), specifically the impacts of lipid and lignin content. Five tree species were selected to span a range of lignin and lipid contents. Linear isotherms were obtained for all sampled species over a limited concentration range (2 microg/ mL < C(gas) < 12 microg/mL), and equilibrium distribution coefficients (K(d)) were linearly correlated to lipid (R2 > 0.83) but not lignin (R2 < 0.4) content. Lipid content was generally higher in bark than in wood cores, so mass concentrated in this tissue. Diffusion into trees was modeled, showing mass transfer resistance in bark was different from wood cores. Diffusion coefficients for bark were 2-10 times less than those for wood cores for all species, and diffusion was linearly related to lipid content (R2 > 0.96) and sorption coefficients (R2 > 0.83). Data from this study and previous research were used to develop the following correlation between the diffusion coefficient and relevant plant and chemical parameters for branch samples: D = (-7 x 10(-11)) x [f(lipid) x 10 (l.48 x logKow+0.54)] + 4 x 10(-8).

  5. The influence of incomplete or unavailable information on environmental impact assessment in the USA

    SciTech Connect

    Atkinson, Samuel F. . E-mail: atkinson@unt.edu; Canter, Larry W. . E-mail: envimptr@aol.com; Ravan, Melanie D. . E-mail: melanie.raven@navy.mil

    2006-07-15

    One of the more common activities of environmental scientists in the United States is the preparation of environmental assessments or environmental impact statements in response to the mandates of the National Environmental Policy Act. The central thesis of this paper revolves around a frequent dilemma those scientists face: how to proceed with the environmental impact analysis when information on potential impacts is incomplete or unavailable. The paper examines how the 'hard look' standard that U.S. courts have imposed upon agencies considering proposed actions came about. Further, U.S. courts have said agencies cannot make arbitrary and capricious decisions when deciding to build a project, implement a plan, issue a permit or other give other approvals, and this paper discusses how the courts have defined what arbitrary and capricious decision are, especially when decisions are made when information about impacts is incomplete or unavailable. The paper examines why agencies win or lose lawsuits filed against the environmental assessments or environmental impact statements they write, focusing on those cases that have occurred after the Supreme Court ruled on the issue in 1989. The paper suggests recommendations to environmental scientists faced with incomplete or unavailable information when preparing an environmental assessment or environmental impact statement in the U.S.

  6. Impact of the collective diffusion of charged nanoparticles in the convective/capillary deposition directed by receding contact lines.

    PubMed

    Noguera-Marín, Diego; Moraila-Martínez, Carmen Lucía; Cabrerizo-Vílchez, Miguel; Rodríguez-Valverde, Miguel Angel

    2016-02-01

    The motion of electrically charged particles under crowding conditions and subjected to evaporation-driven capillary flow might be ruled by collective diffusion. The concentration gradient developed inside an evaporating drop of colloidal suspension may reduce by diffusion the number of particles transported toward the contact line by convection. Unlike self-diffusion coefficient, the cooperative diffusion coefficient of interacting particles becomes more pronounced in crowded environments. In this work, we examined experimentally the role of the collective diffusion of charge-stabilized nanoparticles in colloidal patterning. To decouple the sustained evaporation from the contact line motion, we conducted evaporating menisci experiments with driven receding contact lines at low capillary number. This allowed us to explore convective assembly at fixed and low bulk concentration, which enabled to develop high concentration gradients. At fixed velocity of receding contact line, we explored a variety of substrate-particle systems where the particle-particle electrostatic interaction was changed (via p H) as well as the substrate receding contact angle and the relative humidity. We found that the particle deposition directed by receding contact lines may be controlled by the interplay between evaporative convection and collective diffusion, particularly at low particle concentration.

  7. Impact of polyethyleneglycol addition on diffusion coefficients in binary ionic liquid electrolytes composed of dicationic ionic liquid and polyethyleneglycol.

    PubMed

    Wu, Tzi-Yi; Su, Shyh-Gang; Chiu, Chuen-Lin; Kuo, Chung-Wen; Tung, Yi-Hsuan

    2017-05-12

    We conduct a comparative study of conductivity and diffusion coefficient of two dicationic ionic liquids (3,3'-(octane-1,8-diyl)bis(1-ethyl-3-imidazolium) bis(trifluoromethylsulfonyl)amide ([IMCI][TFSI], S1) and 3,3'-(2,2'-(ethane-1,2-diylbis(oxy))bis(ethane-2,1-diyl))bis(1-ethyl-3-imidazolium) bis(trifluoromethylsulfonyl)amide ([IMOI][TFSI], S2)) at various temperatures. The diffusion coefficients of cation and anion in ionic liquids are determined by using pulse gradient spin-echo nuclear magnetic resonance method. S2 shows lower viscosity, higher conductivity, and higher diffusion coefficient than those of S1. Moreover, the influence of polyethyleneglycol (PEG200, Mw  = 200) addition in PEG200/IL binary solutions is investigated. PEG200/S1 binary solutions show lower viscosity, higher conductivity, and higher diffusion coefficient than those of neat S1. The experimental molar conductivity (Λ) of neat IL and PEG200/IL binary solutions is lower than that of the calculated molar conductivity (ΛNMR ) from pulse gradient spin-echo nuclear magnetic resonance method at various temperatures, indicating that not all the diffusion species belong to the ionic conduction. In other words, NMR diffusion measurements comprise charged and paired (without charge) ions. Copyright © 2017 John Wiley & Sons, Ltd. Copyright © 2017 John Wiley & Sons, Ltd.

  8. Systems Life Cycle: Strategy for Managing the Impact of Information Systems on Nursing

    PubMed Central

    Jacobsen, Teresa J.; Fennell, Steven E.

    1983-01-01

    The impact of information systems on nursing is profound given that a major component of patient care is information handling. The use of the systems life cycle framework for managing change is a strategy that should employ the nursing administrator's commitment from feasibility study to evaluation of any system implementation. Generally, problems will be encountered during various phases of the systems life cycle that must be anticipated by utilizing planned, flexible interventions to cope with the impact of organizational change. Issues which require a commitment from the nursing profession in assisting administration with supporting patient care in new technological environments will also be explored.

  9. The Impact of Iterative Reconstruction in Low-Dose Computed Tomography on the Evaluation of Diffuse Interstitial Lung Disease.

    PubMed

    Lim, Hyun-Ju; Chung, Myung Jin; Shin, Kyung Eun; Hwang, Hye Sun; Lee, Kyung Soo

    2016-01-01

    To evaluate the impact of iterative reconstruction (IR) on the assessment of diffuse interstitial lung disease (DILD) using CT. An American College of Radiology (ACR) phantom (module 4 to assess spatial resolution) was scanned with 10-100 effective mAs at 120 kVp. The images were reconstructed using filtered back projection (FBP), adaptive statistical iterative reconstruction (ASIR), with blending ratios of 0%, 30%, 70% and 100%, and model-based iterative reconstruction (MBIR), and their spatial resolution was objectively assessed by the line pair structure method. The patient study was based on retrospective interpretation of prospectively acquired data, and it was approved by the institutional review board. Chest CT scans of 23 patients (mean age 64 years) were performed at 120 kVp using 1) standard dose protocol applying 142-275 mA with dose modulation (high-resolution computed tomography [HRCT]) and 2) low-dose protocol applying 20 mA (low dose CT, LDCT). HRCT images were reconstructed with FBP, and LDCT images were reconstructed using FBP, ASIR, and MBIR. Matching images were randomized and independently reviewed by chest radiologists. Subjective assessment of disease presence and radiological diagnosis was made on a 10-point scale. In addition, semi-quantitative results were compared for the extent of abnormalities estimated to the nearest 5% of parenchymal involvement. In the phantom study, ASIR was comparable to FBP in terms of spatial resolution. However, for MBIR, the spatial resolution was greatly decreased under 10 mA. In the patient study, the detection of the presence of disease was not significantly different. The values for area under the curve for detection of DILD by HRCT, FBP, ASIR, and MBIR were as follows: 0.978, 0.979, 0.972, and 0.963. LDCT images reconstructed with FBP, ASIR, and MBIR tended to underestimate reticular or honeycombing opacities (-2.8%, -4.1%, and -5.3%, respectively) and overestimate ground glass opacities (+4.6%, +8.9%, and

  10. The Impact of Iterative Reconstruction in Low-Dose Computed Tomography on the Evaluation of Diffuse Interstitial Lung Disease

    PubMed Central

    Lim, Hyun-ju; Shin, Kyung Eun; Hwang, Hye Sun; Lee, Kyung Soo

    2016-01-01

    Objective To evaluate the impact of iterative reconstruction (IR) on the assessment of diffuse interstitial lung disease (DILD) using CT. Materials and Methods An American College of Radiology (ACR) phantom (module 4 to assess spatial resolution) was scanned with 10–100 effective mAs at 120 kVp. The images were reconstructed using filtered back projection (FBP), adaptive statistical iterative reconstruction (ASIR), with blending ratios of 0%, 30%, 70% and 100%, and model-based iterative reconstruction (MBIR), and their spatial resolution was objectively assessed by the line pair structure method. The patient study was based on retrospective interpretation of prospectively acquired data, and it was approved by the institutional review board. Chest CT scans of 23 patients (mean age 64 years) were performed at 120 kVp using 1) standard dose protocol applying 142–275 mA with dose modulation (high-resolution computed tomography [HRCT]) and 2) low-dose protocol applying 20 mA (low dose CT, LDCT). HRCT images were reconstructed with FBP, and LDCT images were reconstructed using FBP, ASIR, and MBIR. Matching images were randomized and independently reviewed by chest radiologists. Subjective assessment of disease presence and radiological diagnosis was made on a 10-point scale. In addition, semi-quantitative results were compared for the extent of abnormalities estimated to the nearest 5% of parenchymal involvement. Results In the phantom study, ASIR was comparable to FBP in terms of spatial resolution. However, for MBIR, the spatial resolution was greatly decreased under 10 mA. In the patient study, the detection of the presence of disease was not significantly different. The values for area under the curve for detection of DILD by HRCT, FBP, ASIR, and MBIR were as follows: 0.978, 0.979, 0.972, and 0.963. LDCT images reconstructed with FBP, ASIR, and MBIR tended to underestimate reticular or honeycombing opacities (-2.8%, -4.1%, and -5.3%, respectively) and

  11. Impact and user satisfaction of a clinical information portal embedded in an electronic health record.

    PubMed

    Tannery, Nancy H; Epstein, Barbara A; Wessel, Charles B; Yarger, Frances; LaDue, John; Klem, Mary Lou

    2011-01-01

    In 2008, a clinical information tool was developed and embedded in the electronic health record system of an academic medical center. In 2009, the initial information tool, Clinical-e, was superseded by a portal called Clinical Focus, with a single search box enabling a federated search of selected online information resources. To measure the usefulness and impact of Clinical Focus, a survey was used to gather feedback about users' experience with this clinical resource. The survey determined what type of clinicians were using this tool and assessed user satisfaction and perceived impact on patient care decision making. Initial survey results suggest the majority of respondents found Clinical Focus easy to navigate, the content easy to read, and the retrieved information relevant and complete. The majority would recommend Clinical Focus to their colleagues. Results indicate that this tool is a promising area for future development.

  12. Impact and User Satisfaction of a Clinical Information Portal Embedded in an Electronic Health Record

    PubMed Central

    Tannery, Nancy H; Epstein, Barbara A; Wessel, Charles B; Yarger, Frances; LaDue, John; Klem, Mary Lou

    2011-01-01

    In 2008, a clinical information tool was developed and embedded in the electronic health record system of an academic medical center. In 2009, the initial information tool, Clinical-e, was superseded by a portal called Clinical Focus, with a single search box enabling a federated search of selected online information resources. To measure the usefulness and impact of Clinical Focus, a survey was used to gather feedback about users' experience with this clinical resource. The survey determined what type of clinicians were using this tool and assessed user satisfaction and perceived impact on patient care decision making. Initial survey results suggest the majority of respondents found Clinical Focus easy to navigate, the content easy to read, and the retrieved information relevant and complete. The majority would recommend Clinical Focus to their colleagues. Results indicate that this tool is a promising area for future development. PMID:22016670

  13. Impact of a boron rich layer on minority carrier lifetime degradation in boron spin-on dopant diffused n-type crystalline silicon solar cells

    NASA Astrophysics Data System (ADS)

    Singha, Bandana; Singh Solanki, Chetan

    2016-03-01

    In the production of n-type crystalline silicon solar cells with boron diffused emitters, the formation of a boron rich layer (BRL) is a common phenomenon and is largely responsible for bulk lifetime degradation. The phenomenon of BRL formation during diffusion of boron spin-on dopant and its impact on bulk lifetime degradation are investigated in this work. The BRL formed beneath the borosilicate glass layer has thicknesses varying from 10 nm-150 nm depending on the diffusion conditions. The effective and bulk minority carrier lifetimes, measured with Al2O3 deposited layers and a quinhydron-methanol solution, show that carrier lifetime degradation is proportional to the BRL thicknesses and their surface recombination velocities. The controlled diffusion processes and different oxidation techniques used in this work can partially reduce the BRL thickness and improve carrier lifetime by more than 10%. But for BRL thicknesses higher than 50 nm, different etching techniques further lower the carrier lifetime and the degradation in the device cannot be recovered.

  14. NASA/DoD Aerospace Knowledge Diffusion Research Project. Paper 31: The information-seeking behavior of engineers

    NASA Technical Reports Server (NTRS)

    Pinelli, Thomas E.; Bishop, Ann P.; Barclay, Rebecca O.; Kennedy, John M.

    1993-01-01

    Engineers are an extraordinarily diverse group of professionals, but an attribute common to all engineers is their use of information. Engineering can be conceptualized as an information processing system that must deal with work-related uncertainty through patterns of technical communications. Throughout the process, data, information, and tacit knowledge are being acquired, produced, transferred, and utilized. While acknowledging that other models exist, we have chosen to view the information-seeking behavior of engineers within a conceptual framework of the engineer as an information processor. This article uses the chosen framework to discuss information-seeking behavior of engineers, reviewing selected literature and empirical studies from library and information science, management, communications, and sociology. The article concludes by proposing a research agenda designed to extend our current, limited knowledge of the way engineers process information.

  15. Radiative Impacts of Further Arctic Sea Ice Melt: Using past Observations to Inform Future Climate Impacts

    NASA Technical Reports Server (NTRS)

    Pistone, K.; Eisenman, I.; Ramanathan, V.

    2017-01-01

    The Arctic region has seen dramatic changes over the past several decades, from polar amplification of global temperature rise to ecosystem changes to the decline of the sea ice. While there has been much speculation as to when the world will see an ice-free Arctic, the radiative impacts of an eventual disappearance of the Arctic sea ice are likely to be significant regardless of the timing. Using CERES radiation and microwave satellite sea ice data, Pistone et al (2014) estimated the radiative forcing due to albedo changes associated with the Arctic sea ice retreat over the 30 years of the satellite data record. In this study, we found that the Arctic Ocean saw a decrease in all-sky albedo of 4% (from 52% to 48%), for an estimated increase in solar heating of 6.4 W/m(exp 2) between 1979 and 2011, or 0.21 W/m(exp 2) when averaged over the globe. This value is substantial--approximately 25% as large as the forcing due to the change in CO2 during the same period. Here we update and expand upon this previous work and use the CERES broadband shortwave observations to explore the radiative impacts of a transition to completely ice-free Arctic Ocean. We estimate the annually-averaged Arctic Ocean planetary albedo under ice-free and cloud-free conditions to be 14% over the region, or approximately 25% lower in absolute terms than the Arctic Ocean cloud-free albedo in 1979. However, the question of all-sky conditions (i.e. including the effects of clouds) introduces a new level of complexity. We explore several cloud scenarios and the resultant impact on albedo. In each of these cases, the estimated forcing is not uniformly distributed throughout the year. We describe the relative contributions of ice loss by month as well as the spatial distributions of the resulting changes in absorbed solar energy. The seasonal timing and location—in addition to magnitude—of the altered solar absorption may have significant implications for atmospheric and ocean dynamics in the

  16. The impact of star physicians on diffusion of a medical technology: the case of laparoscopic gastric bypass surgery.

    PubMed

    Shinn, Laura

    2014-01-01

    Using data on all bariatric surgeries performed in the state of Pennsylvania from 1995 through 2007, this article uses logistic and OLS regressions to measure the effect of star physicians and star hospitals on the diffusion of an innovation in bariatric surgery called laparoscopic gastric bypass surgery (LGBS). This article tests for effects at both the hospital and physician level. Compared to hospitals with no star physicians (11 percent adoption rate), those with star physicians on staff show a much higher adoption rate (89 percent). Compared to hospitals that are not classified as star hospitals (13 percent diffusion rate), hospitals with star status show a much higher diffusion rate (87 percent from first quarter 2000 to fourth quarter 2001); being a star hospital raises the likelihood of that hospital diffusing LCBS from 13 percent to 87 percent. At the physician level, the empirical results indicate that star physicians exert positive asymmetric influence on the adoption and utilization rates of nonstars at the same hospital. Stars are those who: (1) graduated from a Top 30 medical school, (2) completed residency at a Top 30 hospital, or (3) are included in a Castle Connolly Top Doctors publication. The results of this article support earlier work on the role of key individuals in technology diffusion. It extends research on medical technology diffusion by testing a new data set for a chronic disease treatment. JEL classifications: D2, I10, I11, L2, O33. D2 production and organizations; L2 firm objectives, organization and behavior; I10 health general; I11 Analysis of health care markets; O33 technological change: choices and consequences; diffusion processes.

  17. Evaluating the impact of investments in information technology on structural inertia in health organizations.

    PubMed

    Bewley, Lee W

    2010-01-01

    Structural inertia is the overall capacity of an organization to adapt within a market environment. This paper reviews the impact of healthcare investments in information management/information technology (IM/IT) on the strategic management concept of structural inertia. Research indicates that healthcare executives should consider the relative state of structural inertia for their firms and match them with potential IM/IT solutions. Additionally, organizations should favorably consider IM/IT solutions that are comparatively less complex.

  18. Effect of Audiovisual Treatment Information on Relieving Anxiety in Patients Undergoing Impacted Mandibular Third Molar Removal.

    PubMed

    Choi, Sung-Hwan; Won, Ji-Hoon; Cha, Jung-Yul; Hwang, Chung-Ju

    2015-11-01

    The authors hypothesized that an audiovisual slide presentation that provided treatment information regarding the removal of an impacted mandibular third molar could improve patient knowledge of postoperative complications and decrease anxiety in young adults before and after surgery. A group that received an audiovisual description was compared with a group that received the conventional written description of the procedure. This randomized clinical trial included young adult patients who required surgical removal of an impacted mandibular third molar and fulfilled the predetermined criteria. The predictor variable was the presentation of an audiovisual slideshow. The audiovisual informed group provided informed consent after viewing an audiovisual slideshow. The control group provided informed consent after reading a written description of the procedure. The outcome variables were the State-Trait Anxiety Inventory, the Dental Anxiety Scale, a self-reported anxiety questionnaire, completed immediately before and 1 week after surgery, and a postoperative questionnaire about the level of understanding of potential postoperative complications. The data were analyzed with χ(2) tests, independent t tests, Mann-Whitney U  tests, and Spearman rank correlation coefficients. Fifty-one patients fulfilled the inclusion criteria. The audiovisual informed group was comprised of 20 men and 5 women; the written informed group was comprised of 21 men and 5 women. The audiovisual informed group remembered significantly more information than the control group about a potential allergic reaction to local anesthesia or medication and potential trismus (P < .05). The audiovisual informed group had lower self-reported anxiety scores than the control group 1 week after surgery (P < .05). These results suggested that informing patients of the treatment with an audiovisual slide presentation could improve patient knowledge about postoperative complications and aid in alleviating

  19. Nanoparticle diffusion within intestinal mucus: Three-dimensional response analysis dissecting the impact of particle surface charge, size and heterogeneity across polyelectrolyte, pegylated and viral particles.

    PubMed

    Abdulkarim, Muthanna; Agulló, Nuria; Cattoz, Beatrice; Griffiths, Peter; Bernkop-Schnürch, Andreas; Borros, Salvador Gómez; Gumbleton, Mark

    2015-11-01

    Multiple particle tracking (MPT) methodology was used to dissect the impact of nanoparticle surface charge and size upon particle diffusion through freshly harvested porcine jejunum mucus. The mucus was characterised rheologically and by atomic force microscopy. To vary nanoparticle surface charge we used a series of self-assembly polyelectrolyte particles composed of varying ratios of the negatively charged polyacrylic acid polymer and the positively charged chitosan polymer. This series included a neutral or near-neutral particle to correspond to highly charged but near-neutral viral particles that appear to effectively permeate mucus. In order to negate the confounding issue of self-aggregation of such neutral synthetic particles a sonication step effectively reduced particle size (to less than 340 nm) for a sufficient period to conduct the tracking experiments. Across the polyelectrolyte particles a broad and meaningful relationship was observed between particle diffusion in mucus (×1000 difference between slowest and fastest particle types), particle size (104-373 nm) and particle surface charge (-29 mV to +19.5 mV), where the beneficial characteristic promoting diffusion was a neutral or near-neutral charge. The diffusion of the neutral polyelectrolyte particle (0.02887 cm S(-1)×10(-9)) compared favourably with that of a highly diffusive PEGylated-PLGA particle (0.03182 cm(2) S(-1)×10(-9)), despite the size of the latter (54 nm diameter) accommodating a reduced steric hindrance with the mucin network. Heterogeneity of particle diffusion within a given particle type revealed the most diffusive 10% sub-population for the neutral polyelectrolyte formulation (5.809 cm(2) S(-1)×10(-9)) to be faster than that of the most diffusive 10% sub-populations obtained either for the PEGylated-PLGA particle (4.061 cm(2) S(-1)×10(-9)) or for a capsid adenovirus particle (1.922 cm(2) S(-1)×10(-9)). While this study has used a simple self-assembly polyelectrolyte system

  20. Impact of inner-wall reflection on UV reactor performance as evaluated by using computational fluid dynamics: The role of diffuse reflection.

    PubMed

    Li, Wentao; Li, Mengkai; Bolton, James R; Qu, Jiuhui; Qiang, Zhimin

    2017-02-01

    Making use of the reflected ultraviolet (UV) radiation with a reflective inner wall is a promising way to improve UV reactor performance. In this study, the impact of inner-wall reflection on UV reactor performance was evaluated in annular single-lamp UV reactors by using computational fluid dynamics, with an emphasis on the role of diffuse reflection. The UV radiation inside the reactor chamber was simulated using a calibrated discrete ordinates radiation model, which has been proven to be a reliable tool for modeling fluence rate (FR) distributions in UV reactors with a reflective inner wall. The results show that UV reactors with a highly reflective inner wall (Reflectivity = 0.80) had obviously higher FRs and reduction equivalent fluences (REFs) than those with an ordinary inner wall (Reflectivity = 0.26). The inner-wall diffuse reflection further increased the reactor REF, as a result of the elevated volume-averaged FR. The FR distribution uniformity had conditioned contributions to UV reactor performance. Specifically, in UV reactors with a plug-like flow the FR distribution uniformity contributed to the REF to some extent, while in UV reactors with a mixed flow it had little influence on the REF. This study has evaluated, for the first time, the impact of inner-wall diffuse reflection on UV reactor performance and has renewed the understanding about the contribution of FR distribution uniformity to UV reactor performance. Copyright © 2016 Elsevier Ltd. All rights reserved.

  1. Impact of information cost and switching of trading strategies in an artificial stock market

    NASA Astrophysics Data System (ADS)

    Liu, Yi-Fang; Zhang, Wei; Xu, Chao; Vitting Andersen, Jørgen; Xu, Hai-Chuan

    2014-08-01

    This paper studies the switching of trading strategies and its effect on the market volatility in a continuous double auction market. We describe the behavior when some uninformed agents, who we call switchers, decide whether or not to pay for information before they trade. By paying for the information they behave as informed traders. First we verify that our model is able to reproduce some of the stylized facts in real financial markets. Next we consider the relationship between switching and the market volatility under different structures of investors. We find that there exists a positive relationship between the market volatility and the percentage of switchers. We therefore conclude that the switchers are a destabilizing factor in the market. However, for a given fixed percentage of switchers, the proportion of switchers that decide to buy information at a given moment of time is negatively related to the current market volatility. In other words, if more agents pay for information to know the fundamental value at some time, the market volatility will be lower. This is because the market price is closer to the fundamental value due to information diffusion between switchers.

  2. [Economic impact of informal care after the establishment of the law of dependence in Spain].

    PubMed

    del Pozo Rubio, Raúl; Escribano Sotos, Francisco

    2012-01-01

    The Law of Dependence keeps the informal caregiver´s role, incorporating a specific economic benefit. The aims of this work are 1) to analyze the effect of the Law on informal care existence, and 2) to value the economic impact in the Law, disaggregated by financier. A cross-section study has been conducted from a representative sample of the dependent population in Cuenca (Spain) in February, 2009. We have obtained information for people with level II and III of dependence. A care service delivery simulation is used to quantify the economic impact of informal care to Cuenca (sample), Castilla-La Mancha and Spain. Informal care delivery is assigned in 81,74% of dependency benefits. Total costs of care service delivery is reduced between 36,51% and 80,53% if informal care exits, disaggregated into savings of 122,97-251,04% for user and 23,30-54,47% for public administration. Average estimated copayment for user is 13,25% for real sample, and it rises to 25,77% when it is supposed informal care extinguishes. Informal care is widespread in the Law, and it implies an important household and public resources saving: for household due to the assumption a smaller copayment that theoretical established, which is assumed by Autonomous Communities; in turn, for public administration, because of the fact economic deliveries require fewer resources.

  3. Impact of informing overweight individuals about the role of genetics in obesity: an online experimental study.

    PubMed

    Lippa, Natalie C; Sanderson, Saskia C

    2013-01-01

    Increasing public awareness of obesity genetics could have beneficial or harmful effects on overweight individuals. This study examined the impact of genetic information on weight-related cognitions as well as interest in personalized genetic information about obesity among overweight individuals. Online survey respondents (n = 655) were randomly assigned to read either genetic, gene-environment, or nongenetic obesity causal information. Fifty-two percent of the participants were female, 82.4% were White, 45% had an annual income of USD <40,000, and the mean BMI was 32.5. Internalized weight stigma was measured using the Weight Bias Internalization Scale. Participants in the genetic and gene-environment conditions were more likely to believe genetics increase obesity risk than participants in the nongenetic condition (both p < 0.05); however, they did not differ regarding internalized weight stigma. Sixty-four percent of the participants expressed interest in receiving personalized genetic information about their obesity risk. Dissemination of information about obesity genetics may have neither a beneficial nor a harmful impact on how overweight individuals perceive themselves. Some overweight individuals may be interested in receiving personalized genetic information. The actual effects of obesity genetic information being incorporated into public health messages and of personalized genetic information on obesity prevention and treatment interventions remain to be seen. © 2013 S. Karger AG, Basel.

  4. NASA/DOD Aerospace Knowledge Diffusion Research Project. Paper 20: Engineers as information processors: A survey of US aerospace engineering faculty and students

    NASA Technical Reports Server (NTRS)

    Holland, Maurita Peterson; Pinelli, Thomas E.; Barclay, Rebecca O.; Kennedy, John M.

    1991-01-01

    U.S. aerospace engineering faculty and students were surveyed as part of the NASA/DoD Aerospace Knowledge Research Project. Faculty and students were viewed as information processors within a conceptual framework of information seeking behavior. Questionnaires were received from 275 faculty members and 640 students, which were used to determine: (1) use and importance of information sources; (2) use of specific print sources and electronic data bases; (3) use of information technology; and (4) the influence of instruction on the use of information sources and the products of faculty and students. Little evidence was found to support the belief that instruction in library or engineering information use has significant impact either on broadening the frequency or range of information products and sources used by U.S. aerospace engineering students.

  5. The impact of Medicines Information enquiry answering on patient care and outcomes.

    PubMed

    Bramley, Diane M; Innes, Alison J; Duggan, Catherine; Oborne, C Alice

    2013-12-01

    To determine the impact of advice provided by UK Medicines Information (MI) services on patient care and outcomes. Healthcare professionals who contacted MI centres with enquiries related to specific patients in 35 UK National Health Service hospitals completed questionnaires before and after receiving MI advice. A multidisciplinary expert panel rated the impact in a sample of enquiries. One investigator used the panel's ratings and principles to rate all enquiries. Of 179 completed questionnaire pairs, 178 (99%) enquirers used the advice provided. Most (145, 81%) judged advice had a positive impact: 110 (61.5%) on patient care, 35 (19.6%) on patient outcome. Medicines Information pharmacists actively advised on issues not previously identified by enquirers in 35 cases (19.6%). The expert panel judged that in 19/20 (95%) cases, advice had a positive impact on patient care or outcome, mainly due to risk reduction. Agreement was high between expert panel and enquirers' ratings of impact: 12 (60%) full agreement; 16 (80%) agreement within one point. The investigator's impact rating of the full sample was positive for 162 (92%) enquiries: 82 (47%) on patient care and 80 (45%) on actual or expected patient outcome. Enquirers and an independent expert panel both determined that MI services provided useful patient-specific advice that impacted positively on patients. Reduction of risk was central to this impact. MI pharmacists frequently identified and advised on issues that clinicians using the service had not recognised themselves, this generally had a positive impact on patients. © 2013 The Authors. IJPP © 2013 Royal Pharmaceutical Society.

  6. Informed RESTORE: A Method for Robust Estimation of Diffusion Tensor from Low Redundancy Datasets in the Presence of Physiological Noise Artifacts

    PubMed Central

    Chang, Lin-Ching; Walker, Lindsay; Pierpaoli, Carlo

    2013-01-01

    Physiological noise artifacts, especially those originating from cardiac pulsation and subject motion, are common in clinical DT-MRI acquisitions. Previous works show that signal perturbations produced by artifacts can be severe and neglecting to account for their contribution can result in erroneous diffusion tensor values. The Robust Estimation of Tensors by Outlier Rejection (RESTORE) method has been shown to be an effective strategy for improving tensor estimation on a voxel-by-voxel basis in the presence of artifactual data points in diffusion weighted images (DWIs). In this paper, we address potential instabilities that may arise when using RESTORE and propose practical constraints to improve its usability. Moreover, we introduce a method, called informed RESTORE (iRESTORE) designed to remove physiological noise artifacts in datasets acquired with low redundancy (less than 30~40 DWI volumes)—a condition in which the original RESTORE algorithm may converge to an incorrect solution. This new method is based on the notion that physiological noise is more likely to result in signal dropouts than signal increases. Results from both Monte Carlo simulation and clinical diffusion data indicate that iRESTORE performs very well in removing physiological noise artifacts for low redundancy DWI datasets. PMID:22287298

  7. A Two-Layered Diffusion Model Traces the Dynamics of Information Processing in the Valuation-and-Choice Circuit of Decision Making

    PubMed Central

    2014-01-01

    A circuit of evaluation and selection of the alternatives is considered a reliable model in neurobiology. The prominent contributions of the literature to this topic are reported. In this study, valuation and choice of a decisional process during Two-Alternative Forced-Choice (TAFC) task are represented as a two-layered network of computational cells, where information accrual and processing progress in nonlinear diffusion dynamics. The evolution of the response-to-stimulus map is thus modeled by two linked diffusive modules (2LDM) representing the neuronal populations involved in the valuation-and-decision circuit of decision making. Diffusion models are naturally appropriate for describing accumulation of evidence over the time. This allows the computation of the response times (RTs) in valuation and choice, under the hypothesis of ex-Wald distribution. A nonlinear transfer function integrates the activities of the two layers. The input-output map based on the infomax principle makes the 2LDM consistent with the reinforcement learning approach. Results from simulated likelihood time series indicate that 2LDM may account for the activity-dependent modulatory component of effective connectivity between the neuronal populations. Rhythmic fluctuations of the estimate gain functions in the delta-beta bands also support the compatibility of 2LDM with the neurobiology of DM. PMID:25254039

  8. Impact of Internet on Schools of Library and Information Science in Thailand.

    ERIC Educational Resources Information Center

    Manmart, Lampang

    This paper looks at how the Internet has impacted library and information science (LIS) schools in Thailand, focusing on how it has been used and changes in the teaching/learning process, curriculum, and programs. Data were collected by questionnaires sent to 146 academic staff in 16 LIS schools, interviews with 16 heads of LIS schools, and…

  9. "Finding Useful Questions: On Bayesian Diagnosticity, Probability, Impact, and Information Gain": Correction to Nelson (2005)

    ERIC Educational Resources Information Center

    Nelson, Jonathan D.

    2007-01-01

    Reports an error in "Finding Useful Questions: On Bayesian Diagnosticity, Probability, Impact, and Information Gain" by Jonathan D. Nelson (Psychological Review, 2005[Oct], Vol 112[4], 979-999). In Table 13, the data should indicate that 7% of females had short hair and 93% of females had long hair. The calculations and discussion in the article…

  10. The Impact of an Informal Science Program on Students' Science Knowledge and Interest

    ERIC Educational Resources Information Center

    Zandstra, Anne Maria

    2012-01-01

    In this sequential explanatory mixed methods study, quantitative and qualitative data were used to measure the impact of an informal science program on eleventh grade students' science knowledge and interest. The local GEAR UP project has been working for six years with a cohort of students who were in eleventh and twelfth grade during the time of…

  11. The Impact of Information Technology on Job Requirements and Qualifications for Catalogers.

    ERIC Educational Resources Information Center

    Khurshid, Zahiruddin

    2003-01-01

    Reviews job advertisements published in "American Libraries" and "College and Research Libraries News" to assess the impact of the use of information technology in libraries on job requirements and qualifications for catalogers. Examines position titles, degree requirements, and required skills, and suggests implications for…

  12. Impact of Using Information Technology in Central University Libraries in India: Results of a Survey

    ERIC Educational Resources Information Center

    Peyala, Venkataramana

    2011-01-01

    Purpose: The purpose of this article is to present the results of a research study conducted to assess the perceptions and opinions of 100 staff working in libraries on the impact of using IT on library housekeeping operations and information services, in eight central university libraries in India. Design/methodology/approach: Data gathering…

  13. "Finding Useful Questions: On Bayesian Diagnosticity, Probability, Impact, and Information Gain": Correction to Nelson (2005)

    ERIC Educational Resources Information Center

    Nelson, Jonathan D.

    2007-01-01

    Reports an error in "Finding Useful Questions: On Bayesian Diagnosticity, Probability, Impact, and Information Gain" by Jonathan D. Nelson (Psychological Review, 2005[Oct], Vol 112[4], 979-999). In Table 13, the data should indicate that 7% of females had short hair and 93% of females had long hair. The calculations and discussion in the article…

  14. Impacting Information Literacy Learning in First-Year Seminars: A Rubric-Based Evaluation

    ERIC Educational Resources Information Center

    Lowe, M. Sara; Booth, Char; Stone, Sean; Tagge, Natalie

    2015-01-01

    The authors conducted a rubric assessment of information literacy (IL) skills in research papers across five undergraduate first-year seminar programs to explore the question "What impact does librarian intervention in first-year courses have on IL performance in student work?" Statistical results indicate that students in courses with…

  15. High Database Prices and Their Impact on Information Access: Is There a Solution?

    ERIC Educational Resources Information Center

    Nelson, Michael L.

    1987-01-01

    Recent trends in the pricing of online database systems are described and their impact on searcher behavior and satisfaction is discussed. A design is proposed for a major research project that would use data gathered by the Information Market Indicators to assess the feasibility of a price-based solution. (CLB)

  16. The Impact of Information Channel on Verbal Recall Among Preschool Aged Television Viewers.

    ERIC Educational Resources Information Center

    Welch, Alicia J.

    A study investigated the learning impact of audio, visual, and audiovisual information channels in televised messages among preschool children. The messages consisted of a half-hour videotape of "Sesame Street" episodes (presented to 48 subjects), and a videotape of an intact "Mister Roger's Neighborhood" program (presented to…

  17. The Impacts of a Computerized Information System on the Integration and Coordination of Human Services

    ERIC Educational Resources Information Center

    Quinn, Robert E.

    1976-01-01

    Examines the impacts of a computerized information system on eight neighborhood service organizations and their funding sources. Discusses how the new system changed interorganizational relationships and what effect those changes had on the integration of services. (Available from American Society for Public Administration, 1225 Connecticut…

  18. A Topographic Image Map of the Sabrina Valles Region Including Information on Large Martian Impact Craters

    NASA Astrophysics Data System (ADS)

    Gehrke, S.; Köhring, R.; Barlow, N. G.; Gwinner, K.; Scholten, F.; Lehmann, H.; Albertz, J.

    2007-03-01

    The Catalog of Large Martian Impact Craters provides detailed information on 42,283 craters >5 km; it is planned to be integrated in the Topographic Image Map Mars 1:200,000 series. Such an update is shown in a special target map, based on HRSC data.

  19. 30 CFR 550.227 - What environmental impact analysis (EIA) information must accompany the EP?

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 2 2012-07-01 2012-07-01 false What environmental impact analysis (EIA) information must accompany the EP? 550.227 Section 550.227 Mineral Resources BUREAU OF OCEAN ENERGY MANAGEMENT... turtles, coastal and marine birds, fish and shellfish, and plant life; (4) Threatened or...

  20. Digital Avionics Information System (DAIS): Impact of DAIS Concept on Life Cycle Cost. Final Report.

    ERIC Educational Resources Information Center

    Goclowski, John C.; And Others

    Designed to identify and quantify the potential impacts of the Digital Avionics Information System (DAIS) on weapon system personnel requirements and life cycle cost (LCC), this study postulated a typical close-air-support (CAS) mission avionics suite to serve as a basis for comparing present day and DAIS configuration specifications. The purpose…

  1. Managing Information Technology as a Catalyst of Change. Track III: The Impact of Quality.

    ERIC Educational Resources Information Center

    CAUSE, Boulder, CO.

    The 1993 CAUSE Conference included eight papers on the adoption of Total Quality Management (TQM), in its various forms, by information technology (IT) sections of colleges and universities. Papers have the following titles and authors: (1) "The Impact of TQM on an IT Organization: The First Eighteen Months" (Paul M. Morris), which…

  2. Examining the Feasibility and Impact of a Graduate Public Administration Course in Evidence-Informed Policy

    ERIC Educational Resources Information Center

    Ouimet, Mathieu; Lapointe, Luc; Léon, Grégory

    2015-01-01

    A pilot controlled before-and-after design was used to assess the impact of a new master-level course in evidence-informed policy making on students' basic knowledge in evidence-based practice. The primary outcome variable was the mean percentage of pre-post improvement on the knowledge test. In the treatment group, the mean percentage of pre-post…

  3. The Impact of Trade Liberalization and Information Technology on India's Manufacturing Sector

    ERIC Educational Resources Information Center

    Sharma, Shruti

    2013-01-01

    This dissertation is an investigation into how trade liberalization and the adoption of information technology have impacted labour and productivity in India's manufacturing sector respectively. The second chapter analyses the relationship between India's liberalization of tariffs on imported intermediate inputs (henceforth input tariff…

  4. Factors that Impact Software Project Success in Offshore Information Technology (IT) Companies

    ERIC Educational Resources Information Center

    Edara, Venkatarao

    2011-01-01

    Information technology (IT) projects are unsuccessful at a rate of 65% to 75% per year, in spite of employing the latest technologies and training employees. Although many studies have been conducted on project successes in U.S. companies, there is a lack of research studying the impact of various factors on software project success in offshore IT…

  5. Factors that Impact Software Project Success in Offshore Information Technology (IT) Companies

    ERIC Educational Resources Information Center

    Edara, Venkatarao

    2011-01-01

    Information technology (IT) projects are unsuccessful at a rate of 65% to 75% per year, in spite of employing the latest technologies and training employees. Although many studies have been conducted on project successes in U.S. companies, there is a lack of research studying the impact of various factors on software project success in offshore IT…

  6. Impacting Information Literacy Learning in First-Year Seminars: A Rubric-Based Evaluation

    ERIC Educational Resources Information Center

    Lowe, M. Sara; Booth, Char; Stone, Sean; Tagge, Natalie

    2015-01-01

    The authors conducted a rubric assessment of information literacy (IL) skills in research papers across five undergraduate first-year seminar programs to explore the question "What impact does librarian intervention in first-year courses have on IL performance in student work?" Statistical results indicate that students in courses with…

  7. The Impact of School Buildings on Learning. Information Capsule. Volume 1204

    ERIC Educational Resources Information Center

    Blazer, Christie

    2012-01-01

    This Information Capsule examines the impact of deteriorating school buildings on students and teachers. Research indicates that students attending schools that are in poor physical condition score lower on achievement tests than students in newer, functional buildings. Studies suggest that several specific factors contribute to lower levels of…

  8. "Taking a Bite Out of Crime": The Impact of a Public Information Campaign.

    ERIC Educational Resources Information Center

    O'Keefe, Garrett J.

    In contrast with earlier findings indicating that public information campaigns produce little change in public attitudes and behaviors, current research suggests that the Advertising Council's "Take a Bite Out of Crime" campaign, initiated in 1979, has had a substantive impact on the public's response to crime prevention. Data from a…

  9. Climate Change Education: Quantitatively Assessing the Impact of a Botanical Garden as an Informal Learning Environment

    ERIC Educational Resources Information Center

    Sellmann, Daniela; Bogner, Franz X.

    2013-01-01

    Although informal learning environments have been studied extensively, ours is one of the first studies to quantitatively assess the impact of learning in botanical gardens on students' cognitive achievement. We observed a group of 10th graders participating in a one-day educational intervention on climate change implemented in a botanical garden.…

  10. A Longitudinal Study of Information Technology Impact on Business Faculty in Distance Education

    ERIC Educational Resources Information Center

    Zhao, Jensen, J.; Alexander, Melody W.; Perrreault, Heidi; Waldman, Lila

    2007-01-01

    This longitudinal study compared business faculty's use of information technology in distance education as well as their perception of the technology's impact on their productivity and technology preferences between 2000 and 2006. Data were collected from 81 professors in 2000 and 140 professors in 2006 at AACSB-accredited business colleges across…

  11. The Impact of Information and Communication Technology on Script Policy in Japan

    ERIC Educational Resources Information Center

    Premaratne, Dilhara D.

    2009-01-01

    Information and communication technology appears to have had a profound impact on language use in Japan. An important issue arising from this is said to be the increase in the use of Chinese characters (kanji) outside the official standard. This development has made a re-appraisal of the existing script policy necessary in order to accommodate the…

  12. Climate Change Education: Quantitatively Assessing the Impact of a Botanical Garden as an Informal Learning Environment

    ERIC Educational Resources Information Center

    Sellmann, Daniela; Bogner, Franz X.

    2013-01-01

    Although informal learning environments have been studied extensively, ours is one of the first studies to quantitatively assess the impact of learning in botanical gardens on students' cognitive achievement. We observed a group of 10th graders participating in a one-day educational intervention on climate change implemented in a botanical garden.…

  13. Impacts of an Information Commons on an Academic Library's Service Points

    ERIC Educational Resources Information Center

    Gohlke, Mary Jo; Ray, Kathlin

    2003-01-01

    The impacts of technology upon traditional library resources are sometimes unexpected. The library at California's University of the Pacific discovered that usage of print materials was dwindling, even though the addition of a 50-station "Information Commons" had bolstered overall library use. At first it was anticipated that the…

  14. A Longitudinal Study of Information Technology Impact on Business Faculty in Distance Education

    ERIC Educational Resources Information Center

    Zhao, Jensen, J.; Alexander, Melody W.; Perrreault, Heidi; Waldman, Lila

    2007-01-01

    This longitudinal study compared business faculty's use of information technology in distance education as well as their perception of the technology's impact on their productivity and technology preferences between 2000 and 2006. Data were collected from 81 professors in 2000 and 140 professors in 2006 at AACSB-accredited business colleges across…

  15. The Impact of Trade Liberalization and Information Technology on India's Manufacturing Sector

    ERIC Educational Resources Information Center

    Sharma, Shruti

    2013-01-01

    This dissertation is an investigation into how trade liberalization and the adoption of information technology have impacted labour and productivity in India's manufacturing sector respectively. The second chapter analyses the relationship between India's liberalization of tariffs on imported intermediate inputs (henceforth input tariff…

  16. Impact of Using Information Technology in Central University Libraries in India: Results of a Survey

    ERIC Educational Resources Information Center

    Peyala, Venkataramana

    2011-01-01

    Purpose: The purpose of this article is to present the results of a research study conducted to assess the perceptions and opinions of 100 staff working in libraries on the impact of using IT on library housekeeping operations and information services, in eight central university libraries in India. Design/methodology/approach: Data gathering…

  17. Professors Are People Too: The Impact of Informal Evaluations of Professors on Students and Professors

    ERIC Educational Resources Information Center

    Kowai-Bell, Neneh; Guadagno, Rosanna E.; Little, Tannah E.; Ballew, Jamie L.

    2012-01-01

    There are websites where individuals anonymously provide informal reviews of professors. What impact do such sites have on student and professor motivational factors? Research suggests that undergraduate students are affected (e.g. Edwards et al. in "J Comput Mediat Commun" 14:368-392, 2009; Kowai-Bell et al. in "Comput Hum Behav" 27(5):1862-1867,…

  18. A Study of the Impact of Representations in Information Retrieval Systems. Annual Technical Report.

    ERIC Educational Resources Information Center

    Katzer, Jeffrey; And Others

    This study conducted to determine representation impact on information items retrieval in terms of precision and recall performance and overlap used the INSPEC "Computers and Control Abstracts" loaded on DIATOM, an online retrieval system based on DIALOG, as the database to be searched. Sixty-nine users provided 84 queries which were…

  19. The Impact of a Computer Based Information System (CBIS) on Foreign Investments Opportunities.

    ERIC Educational Resources Information Center

    Goodwin, Chester

    The purpose of this paper is to analyze the impact that computer based information systems (CBIS) could have on U.S. multinational corporations operating in Canada, particularly in the province of Quebec, and the implications for the North American Free Trade Agreement (NAFTA) that went into effect on January 1, 1994. The study focused on how the…

  20. Diffusion of new technology, health services and information after a crisis: a focus group study of the Sichuan "5.12" Earthquake.

    PubMed

    Zhou, Hong; Shi, Lu; Mao, Yuping; Tang, Juan; Zeng, Yu

    2014-01-01

    The Sichuan "5.12" Earthquake in 2008 occurred in a relatively underdeveloped area in China. The rainy weather, the mountainous environment and the local languages all posed major challenges to the dissemination of information and services after the disaster. By adopting a communication perspective, this study applies the diffusion of innovations theory to investigate how healthcare professionals diffused health technologies, health information and services during the rescue and relief operation. The authors conducted three focus group sessions with the health professionals who had attended to the rescue and relief work of the Sichuan "5.12" Earthquake in 2008. A range of questions regarding the diffusion of innovations were asked during these sessions. The health professionals used their cell phones to communicate with other healthcare providers, disseminated knowledge of health risks and injuries to affected residents with pamphlets and posters and attended daily meetings at the local government offices. They reported on the shortage of maritime satellite cell phones and large-size tents for medical use, and the absence of fully equipped ambulances. Volunteers, local health professionals and local officials provided health information and services in different ways. However, the diffusion of health information and services was less likely to reach those living next to transportation centers, in remote areas and in disaster areas neglected by the media. New communication devices such as cell phones and the mobile Internet enabled medical professionals to coordinate the rescue and relief work after this major natural disaster, at a time when the country's emergency response system still had plenty of room for improvement. In future, the mobile Internet should be used as a means of collecting bottom-up disaster reports so that the media will not neglect any disaster areas as they did during the Sichuan Earthquake. Rescue relief work would have been substantially

  1. Limited information estimation of the diffusion-based item response theory model for responses and response times.

    PubMed

    Ranger, Jochen; Kuhn, Jörg-Tobias; Szardenings, Carsten

    2016-05-01

    Psychological tests are usually analysed with item response models. Recently, some alternative measurement models have been proposed that were derived from cognitive process models developed in experimental psychology. These models consider the responses but also the response times of the test takers. Two such models are the Q-diffusion model and the D-diffusion model. Both models can be calibrated with the diffIRT package of the R statistical environment via marginal maximum likelihood (MML) estimation. In this manuscript, an alternative approach to model calibration is proposed. The approach is based on weighted least squares estimation and parallels the standard estimation approach in structural equation modelling. Estimates are determined by minimizing the discrepancy between the observed and the implied covariance matrix. The estimator is simple to implement, consistent, and asymptotically normally distributed. Least squares estimation also provides a test of model fit by comparing the observed and implied covariance matrix. The estimator and the test of model fit are evaluated in a simulation study. Although parameter recovery is good, the estimator is less efficient than the MML estimator.

  2. Conditions for uniform impact of the plasma of a runaway-electron-induced pulsed diffuse discharge on an anode

    NASA Astrophysics Data System (ADS)

    Erofeev, M. V.; Baksht, E. Kh.; Burachenko, A. G.; Tarasenko, V. F.

    2015-09-01

    The subject matters in this work are (i) the spatial structure of a volume (diffuse) discharge initiated in atmospheric-pressure air in a heavily nonuniform electric field by nanosecond voltage pulses and (ii) the influence of its plasma on the surface of a plane aluminum anode. It is shown that a diffuse discharge initiated by nanosecond voltage pulses makes it possible to uniformly process the anode's surface in atmospheric-pressure air in contrast to a spark discharge, which results in microcracking, locally changes the surface properties, and thereby degrades the surface.

  3. Gyrokinetic study of the impact of the electron to ion heating ratio on the turbulent diffusion of highly charged impurities

    SciTech Connect

    Angioni, C.

    2015-10-15

    A gyrokinetic study based on numerical and analytical calculations is presented, which computes the dependence of the turbulent diffusion of highly charged impurities on the ratio of the electron to the ion heat flux of the plasma. Nonlinear simulations show that the size of the turbulent diffusion of heavy impurities can vary by one order of magnitude with fixed total heat flux and is an extremely sensitive function of the electron to ion heat flux ratio. Numerical linear calculations are found to reproduce the nonlinear results. Thereby, a quasi-linear analytical approach is used to explain the origin of this dependence.

  4. Impact of weak excitatory synapses on chaotic transients in a diffusively coupled Morris-Lecar neuronal network

    SciTech Connect

    Lafranceschina, Jacopo Wackerbauer, Renate

    2015-01-15

    Spatiotemporal chaos collapses to either a rest state or a propagating pulse solution in a ring network of diffusively coupled, excitable Morris-Lecar neurons. Weak excitatory synapses can increase the Lyapunov exponent, expedite the collapse, and promote the collapse to the rest state rather than the pulse state. A single traveling pulse solution may no longer be asymptotic for certain combinations of network topology and (weak) coupling strengths, and initiate spatiotemporal chaos. Multiple pulses can cause chaos initiation due to diffusive and synaptic pulse-pulse interaction. In the presence of chaos initiation, intermittent spatiotemporal chaos exists until typically a collapse to the rest state.

  5. Impact of weak excitatory synapses on chaotic transients in a diffusively coupled Morris-Lecar neuronal network

    NASA Astrophysics Data System (ADS)

    Lafranceschina, Jacopo; Wackerbauer, Renate

    2015-01-01

    Spatiotemporal chaos collapses to either a rest state or a propagating pulse solution in a ring network of diffusively coupled, excitable Morris-Lecar neurons. Weak excitatory synapses can increase the Lyapunov exponent, expedite the collapse, and promote the collapse to the rest state rather than the pulse state. A single traveling pulse solution may no longer be asymptotic for certain combinations of network topology and (weak) coupling strengths, and initiate spatiotemporal chaos. Multiple pulses can cause chaos initiation due to diffusive and synaptic pulse-pulse interaction. In the presence of chaos initiation, intermittent spatiotemporal chaos exists until typically a collapse to the rest state.

  6. Developing Broader Impacts Activities through Informal STEM Education Collaborations and Strategies

    NASA Astrophysics Data System (ADS)

    Bell, James

    2015-03-01

    With the National Science Foundation and other funding agencies' renewed emphasis on broader impacts merit criterion in proposals, investigators and directors of education, outreach and engagement are challenged to identify, plan and implement innovative and transformative activities that engage a variety of audiences in the broader impacts of scientific research. These activities are also often required to have an evaluation plan for assessing the effectiveness of the strategies employed to achieve learning goals or other intended impacts. One approach to developing such plans is to partner with an informal science education institution, program, project or individual to create exhibits, media or programming that will convey the scientific concepts and processes involved in research and engage students and public audiences in appreciation for, and understanding of same. A growing body of evidence -based knowledge about what works for whom and under what conditions in fostering science learning and literacy in informal settings, as well as an expanding network of informal science, technology, engineering and math (STEM) education professionals provide researchers, graduate students and staff resources to tap into as they consider their broader impacts directions. Web infrastructure like the informalscience.org website and others offer aggregated, vetted, and searchable examples of successful partnerships and strategies, as well as access to a community of colleagues working at the nexus of scientific research and informal education for further exploration. Through heightened awareness, stronger connectivity and a growing repository of knowledge, projects like the Center for Advancement of Informal Science Education (CAISE) hope to support and disseminate the results of efforts that are enhancing the quality and visibility of broader impacts activities in whatever form they take.

  7. Does nutrition information on menus impact food choice? Comparisons across two hospital cafeterias.

    PubMed

    Vanderlee, Lana; Hammond, David

    2014-06-01

    Food prepared and consumed away from home accounts for a significant proportion of dietary intake among Canadians. Currently, Canadians receive little or no nutrition information when eating in restaurant and fast-food outlets. The present study examined the impact of nutrition information on menus in hospital cafeterias on noticing and perceived influence of nutrition information and on food consumption. Cross-sectional surveys. Exit surveys (n 1003) were conducted in two hospital cafeterias. The 'intervention' site featured energy (calorie), sodium and fat content on digital menu boards, as well as a health logo for 'healthier' items. The intervention site had also revised its menu items to improve the nutrient profiles. The 'control' site provided limited nutrition information at the point of sale. Cafeteria patrons recruited using the intercept technique. Significantly more respondents at the intervention site reported noticing nutrition information (OR = 7·6, P < 0·001) and using nutrition information to select their food items (OR = 3·3, P < 0·001) compared with patrons at the control site, after adjusting for sociodemographic factors. Patrons at the intervention site consumed significantly less energy (-21 %, P < 0·001), sodium (-23 %, P < 0·001), saturated fat (-33 %, P < 0·001) and total fat (-37 %, P < 0·001) than patrons at the control site. A nutritional programme, including nutrition information on menus and improved nutrition profile of food offerings, was associated with substantial reductions in energy, sodium and fat consumption. The results are consistent with a positive impact of menu labelling.

  8. A community education initiative to improve using online health information: participation and impact.

    PubMed

    Gray, Kathleen; Elliott, Kristine; Wale, Janet

    2013-09-01

    The Internet has become a major source of health information for the general public and has the potential to influence health behaviours; however, most people lack the knowledge and skills to use it insightfully. This paper reports on the evaluation of a community education program, in which a team of clinicians and consumer representatives from a large metropolitan hospital partnered with a major public library to provide free interactive workshops for the general public. The aim of the workshops was to improve participants' ability to find and use evidence-based health information on the Internet. The aim of the evaluation reported here was to study participation in and impact of these workshops. Researchers administered pre- and post-workshop surveys to 89 members of the general public who participated in a workshop. This study found not only similarities in participants' pre-workshop use of online health information compared with population-level studies but also some interesting differences. The workshop was found to have an overall positive impact on changing the way participants intended to look for and use health information in the future, and on improving their knowledge about evidence-based health information, with 63.5% of respondents stating that they would use health information in the future to ask a doctor new questions. These findings offer important evidence of the need to plan nuanced health literacy education and information strategies for the general public.

  9. Exploring the Impact of Information Seeking Behaviors of Online Health Consumers in the Arab World.

    PubMed

    Bahkali, Salwa; Almaiman, Reem; El-Awad, Mamoun; Almohanna, Huda; Al-Surimi, Khaled; Househ, Mowafa

    2016-01-01

    In the Arab world, increasing numbers of people are seeking online health related information for diagnoses, medicine, fitness, pharmaceutical drugs, and smoking cessation programs, among others. Studies exploring the impact of social media channels on health seeking behavior among Arabic users are limited. This study has two goals: (1) describe the prevalence of online health information-seeking behavior in the Arab world, and (2) study the impacts of social media based platforms in helping promote healthy living in the Arab world. In order to gather primary data, a web-based cross-sectional survey with a total of 7013 self-administered questionnaires was sent via SMS messages (n=1278), to Twitter followers of an Arab women's health social media account (n=3630 followers), and WhatsApp messages (n=2105) to participants above 16 years of age representing different socioeconomic groups and within the Arabic speaking world. The findings of this study show high interest among the participants (84.9%) in seeking online health information. Furthermore, reporting online information had an impact on participant health behaviors. Social media can play an important role in strengthening the health care system to provide valuable information, educational programs and interventions to promote healthy life styles among the Arabic people.

  10. NASA/DoD Aerospace Knowledge Diffusion Research Project. Report Number 13. Source Selection and Information Use by U.S. Aerospace Engineers and Scientists: Results of a Telephone Survey

    DTIC Science & Technology

    1992-09-01

    Aerospace Knowledge Diffusion Research Project. Government Information Quarterly 8(2), 219- 233. Shuchman, H. L. (1981). Information Transfer in...Research Project. Reprinted from Government Information Quarterly , Volume 8, No. 2 (1991): 219-233. (Available from AIAA 91A35455.) 1 1 Pinelli, Thomas

  11. Use of diffusion tensor imaging to assess the impact of normobaric hyperoxia within at-risk pericontusional tissue after traumatic brain injury.

    PubMed

    Veenith, Tonny V; Carter, Eleanor L; Grossac, Julia; Newcombe, Virginia F; Outtrim, Joanne G; Nallapareddy, Sridhar; Lupson, Victoria; Correia, Marta M; Mada, Marius M; Williams, Guy B; Menon, David K; Coles, Jonathan P

    2014-10-01

    Ischemia and metabolic dysfunction remain important causes of neuronal loss after head injury, and we have shown that normobaric hyperoxia may rescue such metabolic compromise. This study examines the impact of hyperoxia within injured brain using diffusion tensor imaging (DTI). Fourteen patients underwent DTI at baseline and after 1 hour of 80% oxygen. Using the apparent diffusion coefficient (ADC) we assessed the impact of hyperoxia within contusions and a 1 cm border zone of normal appearing pericontusion, and within a rim of perilesional reduced ADC consistent with cytotoxic edema and metabolic compromise. Seven healthy volunteers underwent imaging at 21%, 60%, and 100% oxygen. In volunteers there was no ADC change with hyperoxia, and contusion and pericontusion ADC values were higher than volunteers (P<0.01). There was no ADC change after hyperoxia within contusion, but an increase within pericontusion (P<0.05). We identified a rim of perilesional cytotoxic edema in 13 patients, and hyperoxia resulted in an ADC increase towards normal (P=0.02). We demonstrate that hyperoxia may result in benefit within the perilesional rim of cytotoxic edema. Future studies should address whether a longer period of hyperoxia has a favorable impact on the evolution of tissue injury.

  12. Impact of the solute exclusion on the bed longitudinal diffusion coefficient and particle intra-tortuosity determined by ISEC.

    PubMed

    Wernert, Véronique; Bouchet, Renaud; Denoyel, Renaud

    2014-01-17

    The effective diffusion coefficient of non retained toluene and polystyrenes compounds was measured by the peak parking method for two columns packed with mesoporous silica. Different models used to predict the effective diffusion are compared. These models include the conventional Knox time-averaged model and some effective medium theory models such as Maxwell, Landauer, Garnett or Torquato models. In all these models the effective intraparticle diffusion coefficient is needed. It is derived here, in non-adsorbing conditions, from internal porosity, hindrance factor, which can be estimated with the Renkin correlation, and internal tortuosity, which can be considered as either constant or calculated by the Weissberg equation τ=1-plnɛ, where ɛ is the accessible particle porosity and p a parameter characteristic of the topology. The experimental effective diffusion coefficients of toluene and polystyrenes were found to be in good agreement with the values predicted by the Maxwell, or Torquato models, provided the internal tortuosity is calculated by using the Weissberg equation. Copyright © 2013 Elsevier B.V. All rights reserved.

  13. Diffusion of Intervention Effects: The Impact of a Family-Based Substance Use Prevention Program on Friends of Participants.

    PubMed

    Rulison, Kelly L; Feinberg, Mark; Gest, Scott D; Osgood, D Wayne

    2015-10-01

    We tested whether effects of the Strengthening Families Program for Youth 10-14 (SFP10-14) diffused from intervention participants to their friends. We also tested which program effects on participants accounted for diffusion. Data are from 5,449 students (51% female; mean initial age = 12.3 years) in the PROmoting School-community-university Partnerships to Enhance Resilience community intervention trial (2001-2006) who did not participate in SFP10-14 (i.e., nonparticipants). At each of five waves, students identified up to seven friends and self-reported past month drunkenness and cigarette use, substance use attitudes, parenting practices, and unsupervised time spent with friends. We computed two measures of indirect exposure to SFP10-14: total number of SFP-attending friends at each wave and cumulative proportion of SFP-attending friends averaged across the current and all previous post-intervention waves. Three years post-intervention, the odds of getting drunk (odds ratio = 1.4) and using cigarettes (odds ratio = 2.7) were higher among nonparticipants with zero SFP-attending friends compared with nonparticipants with three or more SFP-attending friends. Multilevel analyses also provided evidence of diffusion: nonparticipants with a higher cumulative proportion of SFP-attending friends at a given wave were less likely than their peers to use drugs at that wave. Effects from SFP10-14 primarily diffused through friendship networks by reducing the amount of unstructured socializing (unsupervised time that nonparticipants spent with friends), changing friends' substance use attitudes, and then changing nonparticipants' own substance use attitudes. Program developers should consider and test how interventions may facilitate diffusion to extend program reach and promote program sustainability. Copyright © 2015 Society for Adolescent Health and Medicine. Published by Elsevier Inc. All rights reserved.

  14. Impact of French 'Comités de Protection des Personnes' on the readability of informed consent documents (ICD) in biomedical research: more information, but not better information.

    PubMed

    Paris, Adeline; Cracowski, Jean-Luc; Maison, Patrick; Radauceanu, Anca; Cornu, Catherine; Hommel, Marc

    2005-06-01

    Information is the keystone to the participation of subjects in biomedical research. Clear comprehension of the informed consent documents (ICDs) is primordial and a necessary requirement is that they are readable. While submission of a protocol to a French 'Comités de Protection des Personnes' (CPP) is a mandatory step with regard to the French legislation on biomedical research, no published data are available concerning its influence on ICDs readability. The aim of our study was to determine the impact of French CPP on the readability of ICDs, using lexico-syntactic readability indexes and ICDs from four clinical research centres and one clinical research unit. Twenty-five ICDs were analysed. The Flesch score was not modified after CPP review, while the Cordial score was significantly lower [from 4 (1-14) to 1 (1-13), P = 0.014]. The information was longer and more complex following CPP review. No protocol characteristics had any impact on the variation before and after review for either the Flesch or the Cordial indexes, nor on the number of syllables per word. Changes in the total number of words before and after review varied considerably between study centre, supporting heterogeneity of CPP review. Since August 2004, French CPP have to study the intelligibility of ICDs in addition to the scientific and ethic aspects of a research. We show that their current reviews do not increase the readability, while increasing the length of ICDs.

  15. Impact of Health Information Exchange on Emergency Medicine Clinical Decision Making.

    PubMed

    Gordon, Bradley D; Bernard, Kyle; Salzman, Josh; Whitebird, Robin R

    2015-12-01

    The objective of the study was to understand the immediate utility of health information exchange (HIE) on emergency department (ED) providers by interviewing them shortly after the information was retrieved. Prior studies of physician perceptions regarding HIE have only been performed outside of the care environment. Trained research assistants interviewed resident physicians, physician assistants and attending physicians using a semi-structured questionnaire within two hours of making a HIE request. The responses were recorded, then transcribed for qualitative analysis. The transcribed interviews were analyzed for emerging qualitative themes. We analyzed 40 interviews obtained from 29 providers. Primary qualitative themes discovered included the following: drivers for requests for outside information; the importance of unexpected information; historical lab values as reference points; providing context when determining whether to admit or discharge a patient; the importance of information in refining disposition; improved confidence of provider; and changes in decisions for diagnostic imaging. ED providers are driven to use HIE when they're missing a known piece of information. This study finds two additional impacts not previously reported. First, providers sometimes find additional unanticipated useful information, supporting a workflow that lowers the threshold to request external information. Second, providers sometimes report utility when no changes to their existing plan are made as their confidence is increased based on external records. Our findings are concordant with previous studies in finding exchanged information is useful to provide context for interpreting lab results, making admission decisions, and prevents repeat diagnostic imaging.

  16. NASA/DOD Aerospace Knowledge Diffusion Research Project. Paper 26: The relationship between technology policy and scientific and technical information within the US and Japanese aerospace industries

    NASA Technical Reports Server (NTRS)

    Pinelli, Thomas E.; Barclay, Rebecca O.; Kennedy, John M.

    1993-01-01

    Government technology policy has nurtured the growth of the aerospace industry which is vital to both the U.S. and Japanese economies. Japanese technology policy differs significantly from U.S. technology policy, however, particularly with respect to the production, transfer, and use of scientific and technical information (STI). In this paper, we discuss the unique position of the aerospace industry in the U.S. and Japan, U.S. and Japanese aerospace policy, and the role of STI in the process of aerospace innovation. The information-seeking behaviors of U.S. and Japanese aerospace engineers and scientists are compared. The authors advocate the development of innovation-adoption technology and STI policy goals for U.S. aerospace and the inclusion of an aerospace knowledge diffusion transfer system with an 'active' component for scanning and acquiring foreign aerospace technology and STI.

  17. Impact of informal networks on opinion dynamics in hierarchically formal organization

    NASA Astrophysics Data System (ADS)

    Song, Xiao; Shi, Wen; Ma, Yaofei; Yang, Chen

    2015-10-01

    Traditional opinion dynamics model focused mainly on the conditions under which a group of agents would reach a consensus. Conclusion has been gained that continuous opinion dynamics are subject to the constraint that convergent opinion adjustment only proceeds when opinion difference is below a given tolerance. This conclusion is useful but neglected the fact that an organization often consists of overlapped networks including formally hierarchical network and small-world/scale-free informal networks. To study the impact of different types of informal networks on converging speed or the number of opinion clusters, four typical types of informal networks (small-world, scale-free, tree and fully connected) are modeled and proposed as complements to formal communications. Experiments to compare formal network and hybrid networks are then carried out. It is observed that opinion dynamics with supplemented communications of informal networks can benefit convergence speed and reduce opinion clusters. More importantly, it is revealed that three key factors of informal networks affect their impact on formal network. These factors of informal network in descending orders are: agents' tolerances, scale and number of links.

  18. Indicators and protocols for monitoring impacts of formal and informal trails in protected areas

    USGS Publications Warehouse

    Marion, Jeffrey L.; Leung, Yu-Fai

    2011-01-01

    Trails are a common recreation infrastructure in protected areas and their conditions affect the quality of natural resources and visitor experiences. Various trail impact indicators and assessment protocols have been developed in support of monitoring programs, which are often used for management decision-making or as part of visitor capacity management frameworks. This paper reviews common indicators and assessment protocols for three types of trails, surfaced formal trails, unsurfaced formal trails, and informal (visitor-created) trails. Monitoring methods and selected data from three U.S. National Park Service units are presented to illustrate some common trail impact indicators and assessment options.

  19. The Role of Public Policy in Enhancing the Design and Diffusion of Information Systems and Technology for Human Benefit

    NASA Astrophysics Data System (ADS)

    Venable, John; Newman, Peter; Letch, Nick; Ash, Sue

    Technologies for human benefit, such as information systems and information technology, have a key role to play in the realization of quality of life for all citizenry by modern societies. New forms of IS and IT can be developed and used creatively to improve education, health, social equity, environmental conditions, social and environ mental sustainability, government and not-for-profit services, participation in govern ment, and enjoyment of life in general.

  20. From Science to Policy: How Climate Impacts Research Informs Decision-Making (Invited)

    NASA Astrophysics Data System (ADS)

    Hayhoe, K.

    2010-12-01

    Emissions of carbon dioxide from the burning of fossil fuels have ushered in a new epoch where human activities will largely determine the evolution of Earth’s climate. Emissions reductions choices made today will determine the impacts that will be experienced not just over the next few decades, but in coming centuries and even millennia. Because carbon dioxide in the atmosphere is long-lived, continued emissions will effectively lock the earth and future generations into a range of impacts, some severe enough to constitute the "dangerous anthropogenic interference" first described by the United Nations Framework Convention on Climate Change in 1990. Due to the urgency of this problem, climate science cannot be conducted in a vacuum that neglects the practical implications of its research. Science has a responsibility to provide sound information relevant to policy and planning, chief among this being an understanding of the potential consequences of choices being made today and in coming decades. Policy, in turn, can and should be informed by recent advances in climate science. Regional climate change impact assessments, such as the 2007 Northeast Climate Impacts Assessment, the 2008 Chicago Climate Action Plan, and the 2009 U.S. Global Change Research Program report, “Global Climate Change Impacts in the United States,” clearly delineate the consequences of higher as compared to lower emissions. The 2010 National Research Council report, “Climate Stabilization Targets: Emissions, Concentrations, and Impacts over Decades to Millennia” goes even further, quantifying the outcomes of different global mean temperature thresholds and greenhouse gas stabilization targets in terms of the resulting changes in streamflow, wildfires, crop productivity, extreme hot summers, and sea level rise. Drawing on my experience with these and other efforts to develop a solid scientific basis for climate-related policy decisions, this presentation will highlight some of the